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Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men
Abstract
Catechins, the major component of green tea extract, have various physiologic effects. There are few studies, however, on the effects of catechins on body fat reduction in humans. It has been reported that the body mass index (BMI) correlates with the amount of malondialdehyde and thiobarbituric acid-reactive substances in the blood.
We investigated the effect of catechins on body fat reduction and the relation between oxidized LDL and body fat variables.
After a 2-wk diet run-in period, healthy Japanese men were divided into 2 groups with similar BMI and waist circumference distributions. A 12-wk double-blind study was performed in which the subjects ingested 1 bottle oolong tea/d containing 690 mg catechins (green tea extract group; n = 17) or 1 bottle oolong tea/d containing 22 mg catechins (control group; n = 18).
Body weight, BMI, waist circumference, body fat mass, and subcutaneous fat area were significantly lower in the green tea extract group than in the control group. Changes in the concentrations of malondialdehyde-modified LDL were positively associated with changes in body fat mass and total fat area in the green tea extract group.
Daily consumption of tea containing 690 mg catechins for 12 wk reduced body fat, which suggests that the ingestion of catechins might be useful in the prevention and improvement of lifestyle-related diseases, mainly obesity.
... Contrary to the data on anthropometric variables obtained in this study ( control subjects ingested one bottle of oolong tea daily containing 22 mg of catechins. After 12 weeks, the percentage decreases in weight, BMI, and AC between the experimental and control groups were 1.5%, 1.5%, and 2.0%, respectively (Nagao et al., 2005). ...
... Therefore, Nagao et al. (2005) confirmed the hypothesis that continuous ingestion of catechins extracted from ...
... Camellia sinensis leaves could reduce weight, BMI, and AC in humans. In contrast to this study, in which there was no reduction in these anthropometric parameters, it is concluded that time and the dosage of the plants' milligrams are two determining variables for noticing their reduction in the sample, as the longevity of the study by Nagao et al. (2005) was three times greater than that of this clinical trial and the dosage of catechins was more than doubled when compared to this study; ...
Medicinal plants Equisetum arvense and Camellia sinensis are popularly used in Brazil to treat obesity and diabetes mellitus. To prove the efficacy and safety of its continuous consumption, this study aimed to evaluate whether these plants could induce weight loss, reduction in body mass index and abdominal circumference, decrease in glycemic indexes, and if they could cause liver and kidney toxicity in research participants. For this purpose, applied longitudinal laboratory research was carried out in a sample of 09 healthy adult individuals who consumed daily, for 28 days, manipulated capsules containing the dry extract of each medicinal plant or capsules containing a placebo. Before, during, and after the experimental phase, the anthropometric variables were measured, and the participant's blood was collected for laboratory tests. Therefore, it could be verified that there was no correlation between the consumption of both plants and the occurrence of significant reduction (p < 0.05) in the sample's weight, body mass index, or abdominal circumference during the clinical trial. However, it was observed that the plant Camellia sinensis showed a hypoglycemic effect in its experimental group. In addition, it was found that none of the plants caused changes in the participant's liver and kidney functions, demonstrating the absence of toxicological effects in the tests. The results confirmed the importance of complementary studies that evaluate the therapeutic potential of the medicinal plants used empirically by the Brazilian population to treat different pathologies, predominantly obesity, and diabetes mellitus.
... Tahe effectiveness of green tea and caffeine 3.1 In a study involving 70 overweight Caucasian participants, divided into four groups based on body weight, waist circumference decreased by 4.5% and body weight by 4.6% after three months [12] . Findings indicating that Asian individuals experienced reductions in body fat and body fat indices after taking 400-700 mg of tea catechins daily for 12 weeks support this conclusion [21][22][23][24][25][26]27] . It was demonstrated that consuming a 350 ml tea beverage containing 592.2 mg of catechins daily for 12 weeks led to increases in energy expenditure and dietary fat oxidation. ...
... There was no rise in heart rate observed [17] . Since green tea had no effect on heart rate, diastolic blood pressure, or systolic blood pressure in other short-term studies, it may be appropriate to ignore this slight short-term elevation in blood pressure [13] or extended study [12,[21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] . Green tea and caffeine together can support obesity management by increasing energy expenditure and mitigating the decrease in metabolic rate that often accompanies weight loss. ...
... Masmali and co-workers observed that green tea consumption could negatively affect the tear film quality, measured by the tear ferning test [67]. It was suggested that this effect could be due to the oxidation of the lipid layer and/or the alteration of electrolyte content [68]. On the contrary, a randomized controlled trial that evaluated the efficacy of green tea extract in 60 patients with DED secondary to meibomian gland dysfunction showed an improvement in symptoms, break-up time and meibum quality compared to the control group [69]. ...
... Masmali and co-workers observed that green tea consumption could ne affect the tear film quality, measured by the tear ferning test [67]. It was sugges this effect could be due to the oxidation of the lipid layer and/or the alter electrolyte content [68]. On the contrary, a randomized controlled trial that evalu efficacy of green tea extract in 60 patients with DED secondary to meibomia dysfunction showed an improvement in symptoms, break-up time and meibum compared to the control group [69]. ...
This review aims to discuss the delicate balance between the physiological production of reactive oxygen species and the role of antioxidant nutraceutical molecules in managing radicals in the complex anatomical structure of the eye. Many molecules and enzymes with reducing and antioxidant potential are present in different parts of the eye. Some of these, such as glutathione, N-acetylcysteine, α-lipoic acid, coenzyme Q10, and enzymatic antioxidants, are endogenously produced by the body. Others, such as plant-derived polyphenols and carotenoids, vitamins B2, C, and E, zinc and selenium, and omega-3 polyunsaturated fatty acids, must be obtained through the diet and are considered essential nutrients. When the equilibrium between the production of reactive oxygen species and their scavenging is disrupted, radical generation overwhelms the endogenous antioxidant arsenal, leading to oxidative stress-related eye disorders and aging. Therefore, the roles of antioxidants contained in dietary supplements in preventing oxidative stress-based ocular dysfunctions are also discussed. However, the results of studies investigating the efficacy of antioxidant supplementation have been mixed or inconclusive, indicating a need for future research to highlight the potential of antioxidant molecules and to develop new preventive nutritional strategies.
... Catechins from fruits like pear, apricot, raspberries, strawberries; phytosterols from fruits like oranges, strawberries, apples, bananas, grapes, kiwi, pear, pineapple, watermelon, peach; proanthocyanidin from grape seed; genestin from currants and raisins; daidzen from dried dates and passion fruit; resveratrol from grape skin and many more bioactive phytoconstituents are reported with significant ameliorative effect in NAFLD. In fruits and vegetables, catechins [21][22][23], phytosterols [24][25][26] polyphenolic compounds (Du et al., 2021) [27], carotenoids [28][29][30] and tannins [31] are well-known physiologically active antioxidants recognized for their potentiality to prevent obesity and obesity-related metabolic syndrome [32][33][34]. In phase 2 or 3 clinical trials, the sites of action of drugs are based on their primary locus of activity within the liver. ...
... They exhibit potent antioxidant activity that can reduce the oxidative stress generated in the hepatocytes and are found to be effective against NAFLD. Studies have indicated that catechins can obstruct the oxidized lipid formation thereby reducing the fats in the body and the risk of progressing arteriosclerosis [22]. Studies have also indicated that the anti-inflammatory, lipid metabolism, anti-oxidant related biomarkers, and sterol regulatory element-binding proteins (SREBPs) related genes are the crucial mediators of NAFLD [67,68]. ...
Nonalcoholic fatty liver disease (NAFLD), a chronic liver condition affects a large number of people around the world with a frequency of 25% of all the chronic liver disease worldwide. Several targets viz. anti-inflammatory, anti-apoptotic and, anti-fibrotic factors, anti-oxidant and insulin-sensitizing pathways, metabolic regulators as well as repurposing traditional medications have been studied for the pharmacologic therapy of NAFLD. Newer pharmacotherapies like caspases blockade, agonists of PPAR and farnesoid X receptor agonists are currently being investigated in treating human NAFLD. However, NAFLD has no FDA-approved pharmacological therapy, therefore there is a considerable unmet therapy need. Apart from the conventional treatment regime, the current approaches to treating NAFLD include lifestyle interventions including healthy diet with adequate nutrition and physical activity. Fruits are known to play a key role in the well-being of human health. Fruits are loaded with a repertoire of bioactive phytoconstituents like catechins, phytosterols, proanthocyanidin, genestin, daidzen, resveratrol, magiferin found in fruits like pear, apricot, strawberries, oranges, apples, bananas, grapes, kiwi, pineapple, watermelon, peach, grape seed and skin, mango, currants, raisins, dried dates, passion fruit and many more. These bioactive phytoconstituents are reported to demonstrate promising pharmacological efficacy like reduction in fatty acid deposition, increased lipid metabolism, modulation of insulin signaling pathway, gut microbiota and hepatic inflammation, inhibition of histone acetyltransferase enzymatic activity to name a few. Not only fruits, but their derivatives like oils, pulp, peel, or their preparations are also found to be equally beneficial in various liver diseases like NAFLD, NASH. Although most of the fruits contains potent bioactive phytoconstituents, however, the presence of sugar in fruits put a question mark on the ameliorative property of the fruits and there has been contrasting reports on the glycemic control post fruit consumption in type 2 diabetic patients. This review is an attempt to summarize the beneficial effects of fruit phytoconstituents on NAFLD based on epidemiological, clinical and experimental evidence, focusing especially on their mechanisms of action.
... Esse gasto ocorre por conta de um aumento no efeito termogênico advindo da mediação dos receptores β-adrenérgicos, responsáveis por suprir a expressão gênica da leptina. Essa interação que se dá entre a epigalocatequina galato e a leptina seria o fator responsável pelo aumento de saciedade (NAGAO et al., 2005). ...
... No estudo realizado por Nagao et al. (2005) com 35 indivíduos do sexo masculino que foram divididos em 3 grupos, o primeiro ingeriu 690mg de catequinas provindas do extrato de chá verde, o segundo 22mg de catequinas e o terceiro grupo placebo, no decorrer de 12 semanas. No final da observação o primeiro grupo que ingeriu maior quantidade de catequinas apresentou mudanças na composição corporal em relação ao peso, IMC (Índice de massa corporal), dobras cutâneas, circunferência abdominal e gordura visceral quando comparados aos demais grupos. ...
Introdução:O diagnóstico da cardiopatia congênita repercute na vida da família e de forma mais impactante na vida da mulher que passa a se dedicar ao cuidado do filho, com mudança na rotina de vida exigindo condições emocionais para enfrentar o itinerário do diagnóstico ao tratamento da doença cardíaca. A cirurgia cardíaca e as internações hospitalares recorrentes, incluindo internamento em Unidades de Terapia Intensiva, são períodos que requerem cuidado não apenas ao bebê, mas a mãe que se encontra na instituição hospitalar aguardando a resolutividade do caso para ter sua vida de volta. Objetivo: Descrever roda de conversa realizada com mães de bebês com cardiopatia congênita internados em UTI pós cirurgia cardíaca. Metodologia: Trata-se de estudo descritivo de roda de conversa, realizada com mães de bebês internados em UTI após cirurgia cardíaca, no intuito de permitir a livre expressão de sentimentos, a partilha de experiências e reflexões acerca do que vem vivenciando no curso do adoecimento do filho. Resultados e Discussão: As rodas de conversa têm formação semelhante ao círculo de cultura de Paulo Freire. A roda permitiu a fala, a escuta e a interação entre as mães, com diálogos e reflexões acerca das demandas relevantes da internação e de como melhorar a estadia hospitalar. Os dados mostraram o comportamento receptivo das mães à técnica, com relatos das vivências do diagnóstico à internação para cirurgia do filho e sobre o que esperam após a alta da UTI. Houve troca de informações e apoio entre as mães possibilitando aproximação e amizade entre elas com realidades próximas. Conclusões: Conclui-se que o cuidado ao bebê com cardiopatia congênita deve abranger às mães que aguardam a recuperação da cirurgia cardíaca em ambiente de UTI, no intuito de orientar e minimizar angústias, proporcionando assistência integral a díade, e não apenas ao bebê isoladamente, seguindo os princípios fundamentais do cuidado integral à saúde, promovendo o conforto e melhora da qualidade de vida no ambiente hospitalar.
... Esse gasto ocorre por conta de um aumento no efeito termogênico advindo da mediação dos receptores β-adrenérgicos, responsáveis por suprir a expressão gênica da leptina. Essa interação que se dá entre a epigalocatequina galato e a leptina seria o fator responsável pelo aumento de saciedade (NAGAO et al., 2005). ...
... No estudo realizado por Nagao et al. (2005) com 35 indivíduos do sexo masculino que foram divididos em 3 grupos, o primeiro ingeriu 690mg de catequinas provindas do extrato de chá verde, o segundo 22mg de catequinas e o terceiro grupo placebo, no decorrer de 12 semanas. No final da observação o primeiro grupo que ingeriu maior quantidade de catequinas apresentou mudanças na composição corporal em relação ao peso, IMC (Índice de massa corporal), dobras cutâneas, circunferência abdominal e gordura visceral quando comparados aos demais grupos. ...
... Esse gasto ocorre por conta de um aumento no efeito termogênico advindo da mediação dos receptores β-adrenérgicos, responsáveis por suprir a expressão gênica da leptina. Essa interação que se dá entre a epigalocatequina galato e a leptina seria o fator responsável pelo aumento de saciedade (NAGAO et al., 2005). ...
... No estudo realizado por Nagao et al. (2005) com 35 indivíduos do sexo masculino que foram divididos em 3 grupos, o primeiro ingeriu 690mg de catequinas provindas do extrato de chá verde, o segundo 22mg de catequinas e o terceiro grupo placebo, no decorrer de 12 semanas. No final da observação o primeiro grupo que ingeriu maior quantidade de catequinas apresentou mudanças na composição corporal em relação ao peso, IMC (Índice de massa corporal), dobras cutâneas, circunferência abdominal e gordura visceral quando comparados aos demais grupos. ...
... Esse gasto ocorre por conta de um aumento no efeito termogênico advindo da mediação dos receptores β-adrenérgicos, responsáveis por suprir a expressão gênica da leptina. Essa interação que se dá entre a epigalocatequina galato e a leptina seria o fator responsável pelo aumento de saciedade (NAGAO et al., 2005). ...
... No estudo realizado por Nagao et al. (2005) com 35 indivíduos do sexo masculino que foram divididos em 3 grupos, o primeiro ingeriu 690mg de catequinas provindas do extrato de chá verde, o segundo 22mg de catequinas e o terceiro grupo placebo, no decorrer de 12 semanas. No final da observação o primeiro grupo que ingeriu maior quantidade de catequinas apresentou mudanças na composição corporal em relação ao peso, IMC (Índice de massa corporal), dobras cutâneas, circunferência abdominal e gordura visceral quando comparados aos demais grupos. ...
... Esse gasto ocorre por conta de um aumento no efeito termogênico advindo da mediação dos receptores β-adrenérgicos, responsáveis por suprir a expressão gênica da leptina. Essa interação que se dá entre a epigalocatequina galato e a leptina seria o fator responsável pelo aumento de saciedade (NAGAO et al., 2005). ...
... No estudo realizado por Nagao et al. (2005) com 35 indivíduos do sexo masculino que foram divididos em 3 grupos, o primeiro ingeriu 690mg de catequinas provindas do extrato de chá verde, o segundo 22mg de catequinas e o terceiro grupo placebo, no decorrer de 12 semanas. No final da observação o primeiro grupo que ingeriu maior quantidade de catequinas apresentou mudanças na composição corporal em relação ao peso, IMC (Índice de massa corporal), dobras cutâneas, circunferência abdominal e gordura visceral quando comparados aos demais grupos. ...
... Their efficiency as antioxidants surpasses many other substances, making them a cost-effective choice in food production [8]. Studies on both animals and humans have demonstrated that catechins impact lipid metabolism by reducing triglycerides, total cholesterol [9], and body fat accumulation [10][11][12]. By binding strongly to reactive oxygen species (ROS), they absorb free radicals [1]. ...
Catechins, renowned for their health benefits, have unexamined environmental impacts. This study assessed the toxicity of crude catechin and catechin hydrate on invertebrate larvae, plant, and microalgae. The survival rates of Daphnia magna Straus and Artemia salina L. were monitored every 24 h over a three-day period. The germination rate and radicle length of Lactuca sativa L. was measured every 24 h for four days. Inhibitory effects were evaluated in both freshwater and seawater cultures of Chlorella vulgaris Beijerinck, with cell density recorded every 24 h and yield inhibition calculated after 96 h. Results indicated that increasing catechin concentration and exposure duration decreased the survival rate of D. magna and A. salina. Daphnia magna was more sensitive to catechins than A. salina, with 24 h lethal concentration 50 (LC-50) values of 1174 µg/mL compared to 1895 µg/mL for crude catechin, and 54 µg/mL compared to 153 µg/mL for catechin hydrate. The germination rate and radicle length of L. sativa, along with the cell density of C. vulgaris, decreased with increasing catechin concentration, but remained higher even after prolonged exposure. At low catechin concentrations, C. vulgaris cell density exceeded control levels. This study demonstrates that catechins in aquatic environments can significantly impact ecosystems. At certain concentrations, catechins are toxic and potentially lethal to aquatic organisms. Conversely, at lower concentrations, catechins may promote microalgal growth, suggesting a fertilizing effect. Understanding these dynamics is crucial for maintaining the stability of aquatic ecosystems.
... They act as antioxidants and inhibit the formation of free radicals. It is also known that these flavonoids can inhibit the oxidation of human LDL (low density lipoproteins) and therefore help to prevent coronary artery disease (NAGAO et al. 2005;RIBEIRO DE LIMA et al. 2006). Usually only the diastereomers (+)-catechin and (-)-epicatechin can be found in noteworthy amounts. ...
The effect of berry shrivel, a physiological disorder in grapevine, on the concentration of phenolic compounds in the cultivars 'Zweigelt', 'Pinot Gris' and 'Pinot Blanc' berries was studied. Specific phenolic compounds were analysed by HPLC and compared to concentrations in healthy berries of the same varieties and between the varieties. As resveratrol is often used as a marker for infection or stress induced defence mechanisms in grapevine, it was postulated that resveratrol concentration in the grape berries is positively correlated with berry shrivel. Other phenolic substances such as catechin, epicatecin and viniferin were also analysed to evaluate their potential effect on berry shrivel. Healthy berries from the variety 'Zweigelt' contained significantly more trans-resveratrol, trans-resveratrol-glucoside and ε-viniferin, whereas shriveled berries contained significantly higher concentrations of catechin and epicatechin. The phenolic concentrations were not significantly different between healthy and affected 'Pinot Gris' and 'Pinot Blanc' grape berries, respectively, except for 'Pinot Gris' with significantly higher catechin concentrations in healthy berries compared to shriveled berries. Cis-resveratrol could not be detected in any of the samples and cis-resveratrol-glucoside could not be definitely identified.
... In addition to caffeine, thermogenic supplements are formulated with compounds such as green tea extract. Green tea is valued for its high content of catechins, especially epigallocatechin gallate (EGCG), which works synergistically with caffeine to enhance its lipolytic properties [23][24][25][26][27]. These compounds are believed to stimulate the sympathetic nervous system, increasing energy expenditure and promoting the breakdown of stored fat [28]. ...
Featured Application
This study demonstrates that chronic ingestion of a thermogenic supplement in conjunction with a resistance training program can significantly enhance fat loss while maintaining strength gains in trained individuals. These findings may inform the development of targeted supplementation strategies for individuals seeking to optimize fat loss while engaging in resistance training.
Abstract
As interest in weight management and metabolic health grows, thermogenic supplements have gained attention for their potential to enhance caloric expenditure and fat loss. This study aimed to investigate the effects of chronic thermogenic supplement ingestion on body composition and strength outcomes during an 8-week periodized resistance training program. Thirty-four resistance-trained males were randomized into thermogenic supplementation (TS) (n = 18) or placebo (n = 16) groups in a double-blind, placebo-controlled design. Participants consumed thermogenic or placebo capsules daily, with dosage adjusted midway through the intervention. Body composition was assessed using ultrasound-based body fat analysis, and strength was measured via bench press and back squat one-repetition maximum (1-RM) tests. Results indicated that TS experienced significantly greater reductions in fat mass (−0.65 kg vs. 0.12 kg, p = 0.029) and body fat percentage (−0.89% vs. −0.08%, p = 0.039) compared to the placebo. Both groups demonstrated significant and comparable improvements in squat (TS: 16.87 kg, placebo: 18.47 kg) and bench press strength (TS: 7.80 kg, placebo: 7.13 kg). These findings suggest that thermogenic supplement ingestion can enhance fat loss without impeding strength adaptations. Future research should explore the dose–response effects and applicability of thermogenics in different populations and over extended durations.
... Similarly, the CSE ability depicted strong statistically significant correlations with catechin (0.983, p < 0.01) and Ncaffeoyl-L-DOPA cis (r = 0.847, p < 0.05) (Fig. 4B, Supplementary Table 5). In vitro and in vivo studies have exhibited the ability of flavonoids such as catechin and protocatechuic acid as well as other hydroxycinnamic acids to inhibit lipase activity (Martinez-Gonzalez et al., 2017;Nagao et al., 2005). Phenolic compounds could interact with lipase through hydrophobic interactions, hydrogen bonds, and π-π interactions of the aromatic rings which produce changes in the lipase structure, modifying its activity (Martinez-Gonzalez et al., 2017). ...
... Another critical issue is establishing safe dosage levels of EGCG to optimize therapeutic efficacy while minimizing adverse effects. Current clinical studies on EGCG dosages vary widely, and extrapolation from animal dosages to humans is virtually impossible (244)(245)(246)(247)(248)(249)(250)(251)(252)(253)(254)(255). Safety data from human studies indicate distinct toxicity thresholds for EGCG consumed as a beverage compared to capsules or tablets, necessitating separate consideration of safe intake levels. ...
Catechins, a class of phytochemicals found in various fruits and tea leaves, have garnered attention for their diverse health-promoting properties, including their potential in combating neurodegenerative diseases. Among these catechins, (−)-epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in green tea, has emerged as a promising therapeutic agent due to its potent antioxidant and anti-inflammatory effects. Chronic neuroinflammation and oxidative stress are key pathological mechanisms in neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). EGCG has neuroprotective efficacy due to scavenging free radicals, reducing oxidative stress and attenuating neuroinflammatory processes. This review discusses the molecular mechanisms of EGCG’s anti-oxidative stress and chronic neuroinflammation, emphasizing its effects on autoimmune responses, neuroimmune system interactions, and focusing on the related effects on AD and PD. By elucidating EGCG’s mechanisms of action and its impact on neurodegenerative processes, this review underscores the potential of EGCG as a therapeutic intervention for AD, PD, and possibly other neurodegenerative diseases. Overall, EGCG emerges as a promising natural compound for combating chronic neuroinflammation and oxidative stress, offering novel avenues for neuroprotective strategies in the treatment of neurodegenerative disorders.
... Blood will be collected by nicking the tip of the rat tail. [15] Figure 5 Fasting blood glucose Oral Glucose Tolerance Test (OGTT): For oral glucose tolerance test, animals will be fasted overnight and blood glucose will be estimated using blood glucose test strips at various time periods ( 60, 120 and 180 min ) after giving the oral glucose load (10 ml/kg; 50% w/v). Blood glucose value before giving glucose load will be considered as 0 minute value. ...
Background: TARO (Colocasia esculenta) an herbal plant and used to treat type 2 diabetes in clinical practice, but the potential evidence needs to be provided. Materials and Methods: plant material is collected and extraction completed. Then perform Phytochemical screening. Type 2 diabetic model rats were induced by feeding high fat diet (HFD) . The model rats were given for 4 weeks. Then treaded with herbal medicine Results: After phytochemical study find out lots of active compound. Flavonoids and terpinoids are responsible for anti-diabetic activity. Extract significantly decreased fasting blood glucose at 750 mg/kg. Conclusion: The results display that extract performs anti-diabetic functions in type 2 diabetic rats induced by feeding HFD.
... Acacia polyphenols increased the mRNA expression of fat metabolizing genes like PPAR-α and PPAR-δ in skeletal muscle and lowered the expression of fat acid synthesis-related genes (SREBP-1c, ACC and FAS) in the liver [57]. Green tea catechins have also been proposed as therapeutic agents for body fat reduction [58]. There are two classes of cannabinoids, synthetic cannabinoids (such as WIN 55212-2) and endogenous (eCB), anandamide (ANA), and 2-arachidonoylglycerol, as well as plants such as cannabis sativa (2-AG). ...
Obesity continues to pose significant health challenges worldwide, contributing to various metabolic complications such as insulin resistance, dyslipidemia, and cardiovascular diseases. Current treatment options are limited and often associated with adverse effects. Recently, cannabis and its constituents, particularly cannabinoids such as tetrahydrocannabinol (THC) and cannabidiol (CBD), have emerged as potential therapeutic agents due to their interaction with the endocannabinoid system (ECS). The ECS plays a crucial role in regulating energy balance, food intake, and metabolic processes through cannabinoid receptors, primarily CB1 and CB2. Preclinical studies have demonstrated that activation of CB1 receptors promotes appetite stimulation and weight gain, while blockade of CB1 receptors reduces food intake and body weight. Additionally, cannabinoids have shown promise in improving insulin sensitivity, lipid metabolism, and inflammation. Clinical trials investigating cannabinoid-based therapies for obesity-related complications are limited but suggest potential benefits. However, concerns regarding psychotropic effects, addiction potential, and long-term safety profiles remain. This review aims to summarize the current understanding of the role of cannabis and cannabinoids in the treatment of obesity-related complications, highlighting both the therapeutic potential and the challenges that need to be addressed for their clinical implementation. Future research should focus on elucidating the precise mechanisms of action, optimizing formulations, and conducting well-designed clinical trials to establish the efficacy and safety of cannabinoid-based therapies in managing obesity and its associated metabolic disorders.
... Several studies have revealed a reverse association between catechin intake and obesity [252,253]. A clinical study has shown that consumption of Oolong tea (containing 690 mg vs. 22 mg of catechins) for 12 weeks can cause a significant reduction in body weight, BMI, and adipose tissue [254]. Another study found that consumption of catechin-rich drinks for three months can cause a significant reduction in body fat percentage, body weight, intra-abdominal fat, and waist circumference [255]. ...
Several hallmarks of metabolic syndrome, such as dysregulation in the glucose and lipid metabolism, endothelial dysfunction, insulin resistance, low-to-medium systemic inflammation, and intestinal microbiota dysbiosis, represent a pathological bridge between metabolic syndrome and diabesity, cardiovascular, and neurodegenerative disorders. This review aims to highlight some therapeutic strategies against metabolic syndrome involving integrative approaches to improve lifestyle and daily diet. The beneficial effects of foods containing antioxidant polyphenols, intestinal microbiota control, and physical activity were also considered. We comprehensively examined a large body of published articles involving basic, animal, and human studie, as well as recent guidelines. As a result, dietary polyphenols from natural plant-based antioxidants and adherence to the Mediterranean diet, along with physical exercise, are promising complementary therapies to delay or prevent the onset of metabolic syndrome and counteract diabesity and cardiovascular diseases, as well as to protect against neurodegenerative disorders and cognitive decline. Modulation of the intestinal microbiota reduces the risks associated with MS, improves diabetes and cardiovascular diseases (CVD), and exerts neuroprotective action. Despite several studies, the estimation of dietary polyphenol intake is inconclusive and requires further evidence. Lifestyle interventions involving physical activity and reduced calorie intake can improve metabolic outcomes.
... Total n (%) management. In addition to dairy, the consumption of tea and coffee has also been associated with a lower risk of obesity, according to both epidemiological evidence and experimental studies [45,46]. The beneficial effects of tea are attributed to its rich content of phenolic compounds, which act as potent antioxidants and scavengers of free radicals [47].These compounds contribute to the overall health-promoting properties of tea, including its potential to support weight management efforts. ...
Background/Objective
No previous study has investigated the association between dietary pattern and both general and abdominal obesity risk among adults in Nigeria. This study aimed to evaluate the associations between dietary patterns and the risk of obesity among adult age 18 and above in Ekiti State, Southwestern Nigeria.
Methods and study designs
A total of 1003 adults were included in this cross-sectional study (males = 558; females = 445). Body mass index (BMI) and waist-to-hip (WHR) were used to assess general and abdominal obesity respectively and they were categorized using WHO recommendation. Partial correlation analyses were performed to assess the associations of dietary patterns with BMI and WHR. Prevalence ratio between dietary pattern and both general and abdominal obesity were calculated using Robust Poisson Regression.
Results
The prevalence of general obesity among adults was 15.9%, (11.6% among men and 20.2% among women); abdominal obesity was 32.3% (28.9% among males and 44.5% among females). Four dietary patterns were identified; diversified traditional pattern; typical traditional pattern; milk and bread pattern and egg and fish pattern. Diversified traditional pattern was negatively associated with BMI (PR = 0.571, 95%CI: 0.360 ~ 0.905, p = 0.017), and typical traditional pattern was positively associated with BMI (PR = 1.561, 95% CI: 1.043 ~ 2.339, p = 0.031) and WHR in females (PR = 1.849, 95% CI: 1.256 ~ 2.721, p = 0.005). In comparison to those in the lowest quartile, adults with the highest quartile of the typical traditional pattern had a higher risk for abdominal obesity (PR = 1.849, 95%CI = 1.256 ~ 2.721, p = 0.020).
Conclusion
This study reports an alarming increase in Obesity prevalence among Nigeria adults which is greatly influence by their lifestyle and eating pattern. We found out that a typical traditional food pattern was associated with a higher risk of both general and abdominal obesity, but a diverse traditional food pattern was associated to a reduced risk of general obesity.
... A natural sesquiterpene called abscisic acid (ABA) has demonstrated effectiveness in the management of inflammation brought on by diabetes and obesity. fact, ABA shares structural similarities with common thiazolidinedione diabetic medications; the use of ABA in rats was observed to lower fasting plasma glucose levels (120). Unexpectedly, it has been claimed that ABA can increase the release of insulin from pancreatic cells and that it is an intrinsic pro-inflammatory cytokine in human granulocytes (121). ...
Around the world, obesity and weight gain are becoming more and more prevalent. Numerous comorbidities, including cancer, diabetes, hypertension, cardiovascular diseases, and sleep disorders, are linked to obesity. The key to successful weight loss remains appropriate lifestyle and behavioral strategies, yet upholding such a balanced living is quite difficult. Thus, recently, lifestyle modifications are getting crucial. The main drivers of obesity are insufficient physical activity, immoderate fat and sugar intake, sleep deprivation, and excessive screen time. Considering the requirement to carefully examine natural products with the potential to treat obesity. Many plant products having polyphenols, terpenoids, organosulphur, and phytosterols have been investigated for governing obesity. One of the key contributions to the industry for dietary supplements' overall revenue is the weight loss sector. This article is made to explore the role of various efficient natural products in modifying obesity and their intended target pathways.
... Researchers believed that adding Thioflavin to the green tea extract is the cause of this result [20] . In contrast, another study proved that drinking of beverages containing catechin for 12 weeks showed significant reduction of body and subcutaneous fat in healthy Japanese men but it did not affect the blood lipid profile [21] . They also indicated that the amount of Cateschin was not enough for preventing mussel formation. ...
The purpose of this study was to investigate the effect of aerobic exercise and Malva Sylvestris supplements on the lipid profile, glucose and WHR in obese and inactive women. Fifty-two obese and inactive women with BMI more than 30 and age range of 20-45 years were selected and randomly divided into four groups: control, exercise, supplement and supplement-exercise groups. The exercise included 12 weeks and 3 sessions per week with an intensity of 80-85% heart rate. The results showed that Malva Sylvestris supplement had a significant effect on decrease of blood glucose, triglyceride, cholesterol, LDL, and WHR, and exercise alone had an effect on LDL and blood glucose decline. Supplement and exercising together had a significant effect on decreasing blood glucose, cholesterol, LDL and increasing HDL. Considering the positive effect of sport exercises with appropriate volume and intensity on sugar index and lipid profiles, as well as the effect of Malva Sylvestris supplement on some of these factors, the use of both interventions in inactive and obese women is recommended.
... Moreover, high-calcium diets have been found to enhance lipolysis and preserve thermogenesis during caloric restriction, facilitating more effective weight loss efforts [40]. In addition to dairy, the consumption of tea and coffee has also been associated with a lower risk of obesity, according to both epidemiological evidence and experimental studies [41,42]. The beneficial effects of tea are attributed to its rich content of phenolic compounds, which act as potent antioxidants and scavengers of free radicals [43].These compounds contribute to the overall health-promoting properties of tea, including its potential to support weight management efforts. ...
Background/Objective: No previous study has investigated the association between dietary pattern and both general and abdominal obesity risk among adult in Nigeria. This study aimed to evaluate the associations between dietary patterns and the risk of obesity in the city of Iyin Ekiti, Southwestern Nigeria.
Methods and Study Designs: A total of 1003 adults were included in this cross-sectional study (males = 558; females = 445). BMI and WHR were used to access general and abdominal obesity respectively and they were categorized using WHO recommendation. Partial correlation analyses were performed to assess the associations between dietary patterns an BMI and WHR. Prevalence ratio between dietary pattern and both general and abdominal obesity were calculated using Robust Poisson Regression.
Results: The prevalence of general obesity among adults was 15.9%, (11.6% among men and 20.2% among women); abdominal obesity was 28.9% among males and 44.5% among females. Four dietary pattern was identified; diversified traditional pattern; typical traditional pattern; milk and bread pattern and egg and fish pattern. Diversified traditional pattern was negatively associated with BMI (PR = 0.571, 95%CI: 0.360~0.905, p = 0.017), and typical traditional pattern was positively associated with BMI (PR = 1.561, 95% CI: 1.043~2.339, p = 0.031) and WHR in females (PR = 1.849, 95% CI: 1.256~2.721, p = 0.005). In comparison to those in the lowest quartile, adults with the highest quartile of the typical traditional pattern had a higher risk for abdominal obesity (PR = 1.849, 95%CI = 1.256 ~ 2.721, p = 0.020).
Conclusion: This study reports an alarming increase in Obesity prevalence among Nigeria adults which is greatly influence by their lifestyle and eating pattern. We found out that a typical traditional food pattern was associated with a higher risk of both general and abdominal obesity, but a diverse traditional food pattern was associated to a reduced risk of general obesity.
... In an in vivo investigation, tea catechin extract (100 mg/kg/day) was found to activate brown adipose tissue while also browning white adipose tissue [73]. Consumption of 1 bottle of oolong tea (690 mg catechin for 12 weeks) was found in a clinical research to reduce body weight, BMI, waist circumference, body fat mass, and subcutaneous fat ratio in healthy men [74]. Another study found that consuming catechin-containing beverages (609.3 mg catechin and 68.7 mg caffeine daily for 12 weeks) reduced body weight, visceral fat area, and body fat in individuals with abdominal obesity [75]. ...
Purpose of Review
Propolis is a bee product that has been used for thousands of years. The chemical composition and biological activity of propolis, which has been investigated in the twentieth century, may vary according to location. Propolis polyphenols can induce thermogenesis in brown and beige fat tissue via the uncoupled protein-1 and creatinine kinase metabolic pathways. This review provides a comprehensive investigation of the structural and biological properties of propolis and provides insights into their promising potential strategies in body weight management.
Recent Findings
By raising overall energy expenditure, it might lead to body weight management. Furthermore, the phenolic components artepillin C, quercetin, catechin, and chlorogenic acid found in its composition may have anti-obesogenic effect by stimulating the sympathetic nervous system, enhancing browning in white adipose tissue, and triggering AMP-activated protein kinase activation and mitochondrial biogenesis.
Summary
Propolis, a natural product, is effective in preventing obesity which is a contemporary pandemic.
... This result is in line with the literature, which indicates that the total protein value should be around 1 g/L (40,41). It is important to note that the decrease in concentration in the first few days is due to the consumption of nitrogen by microorganisms during the fermentation process (34). ...
Research background
Research into bacterial cellulose production has been growing rapidly in recent years, as it has a potential use in various applications, such as in the medical and food industries. Previous studies have focused on optimising the production process through various methods, such as using different carbon sources and manipulating environmental conditions. However, further research is still needed to optimise the production process and understand the underlying mechanisms of bacterial cellulose synthesis.
Experimental approach
We used Plackett-Burman and Box-Behnken experimental designs to analyse the effect of different factors on bacterial cellulose production. The fermentation kinetics of the optimised medium was analysed, and the produced cellulose was characterised. This approach was used because it allows the identification of significant factors influencing bacterial cellulose growth, the optimisation of the culture medium and the characterisation of the produced cellulose.
Results and conclusions
The results showed that higher sucrose concentrations, higher kombucha volume fractions and a smaller size of the symbiotic culture of bacteria and yeast were the most important factors for the improvement of bacterial cellulose production, while the other factors had no relevant influence. The optimised medium showed an increase in the concentrations of total phenolic compounds and total flavonoids as well as significant antioxidant activity. The produced pure bacterial cellulose had a high water absorption capacity as well as high crystallinity and thermal stability.
Novelty and scientific contribution
The study makes an important scientific contribution by optimising the culture medium to produce bacterial cellulose more productively and efficiently. The optimised medium can be used for the production of a kombucha-like beverage with a high content of bioactive compounds and for the production of bacterial cellulose with high crystallinity and thermal stability. Additionally, the study highlights the potential of bacterial cellulose as a highly water-absorbent material with applications in areas such as packaging and biomedical engineering.
... One study experimented on how the antioxidant melatonin could help protect cells against oxidative DNA damage induced by Chromium (III) and hydrogen peroxide [11]. Another study found that consumption of teas rich in catechins could reduce body fat [12]. In another study, Dr. Assuncao found that the catechins in green tea slows down the brain function decline during aging [13]. ...
Oxidative DNA damage is caused by free radicals eroding the cell membrane and directly attacking DNA molecules in the cell. This DNA damage plays an important role in the development of cancer. Antioxidants remove free radical intermediates, thereby preventing cell membrane erosion and subsequent DNA damage. Tea leaves are rich in antioxidants, and studies conducted on green tea have reported numerous health benefits; however, those studies left out other types of tea. We evaluated the ability of various tea extracts to protect prostate cells from hydrogen peroxide induced oxidative damage. Cells were treated with black, oolong, green, and white tea extracts and then exposed to hydrogen peroxide for two days, followed by a quantification of viable cells using an MTS assay. Because treatment with white tea extract yielded the greatest cell viability, we hypothesized that an abundant antioxidant in white tea, epigallocatechin-3-gallate (EGCG), might also protect cells from oxidative stress. We found that, indeed, pre-treatment of prostate cells with 50 mg/mL EGCG led to a significant increase in cell viability when compared to the control group (fold change of 2.90), based on MTS assay absorbance. These data suggest that antioxidants in white tea extract, including EGCG, protect prostate cells from oxidative stress in culture, which is suggestive of the health benefits of white tea.
... When the generation of free radicals exceeds the body's antioxidant level, lipid peroxidation occurs, which can be estimated from the level of MDA, which is a reliable sign of the degree of lipid peroxidation. Polyunsaturated fatty acids such as linolenic acid act as a protective constituent against lipid peroxidation by increasing the cellular antioxidants level 32 . MDA level was significantly (P < 0.05) increased in OS, and I rats, while this level gradually decreased when the rats received TO. ...
The present study has been conducted to search out the anti-oxidative and anti-inflammatory potential of leaves of Camellia sinensis L. (Tea oil, TO). Forty-eight rats were included for 14 days experiment namely: Group I was normal to control, Group II was vehicle control, and Group III to VIII rats were subjected to paracetamol at the dose of 15 mg/ kg body weight/day to induce oxidative stress and inflammation (OS and I rats). Group IV to VII rats orally received TO at the dose of 100, 200, 400, 800 mg/kg, respectively and Group VIII received olive oil at 400 mg/kg. Paracetamol causes a significant (p < 0.05) increase in plasma urea, creatinine, glutamine-oxalic-transaminase, glutamate-pyruvate-transaminase, alkaline-phosphatase, interleukin-18, and tissue-injury-molecule-1, malondialdehyde and degeneration of hepatic cells in case of only OS and I rats. But treatment with TO in different doses showed a significant (p < 0.05) decrease above said parameters. We observed a significant (p < 0.05) decrease in superoxide dismutase, catalase, interleukin-10 levels in OS and I rats and also treatment with TO showed a significant (p < 0.05) increase in superoxide dismutase, catalase, interleukin-10 level in group IV to VII compared with only group III rats. Tea oil shows potent antioxidative activities against high-dose paracetamol-induced oxidative stress and inflammation by regulating the levels of pro-inflammatory and anti-inflammatory cytokines, whereas the most effective dose TO was 400 mg/kg.
... Increased mRNA levels of thermogenic genes, including Ucp1 and Ucp2, were induced by EGCG in mice(Jiménez-Zamora et al., 2016).In addition, leptin levels are significantly reduced in rats treated with EGCG (Jiménez-Zamora et al., 2016). A 12-week study conducted on healthy Japanese men found that consumption of 690 mg of tea catechins significantly reduced body weight and fat mass(Nagao et al., 2005). The results of a meta-analysis demonstrated a direct ...
Tea is one of the most commonly consumed beverages in the world. Morocco, Japan,
and China have consumed green tea for centuries. White tea, which is a variety of
green teas, is very popular in China and is highly revered for its taste. Presently, both
teas are consumed in other countries around the world, even as functional ingredients, and novel research is constantly being conducted in these areas. We provide
an update on the health benefits of white and green teas in this review, based on recent research done to present. After a general introduction, we focused on tea's antiobesity and human health-promoting potential, adverse effects, and new approaches
to tea and its bioactive compounds. It has been found that the health benefits of tea
are due to its bioactive components, mainly phenolic compounds. Of these, catechins
are the most abundant. This beverage (or its extracts) has potential anti-inflammatory
and antioxidant properties, which could contribute to body weight control and the
improvement of several chronic diseases. However, some studies have mentioned the
possibility of toxic effects; therefore, reducing tea consumption is a good idea, especially during the last trimester of pregnancy. Additionally, new evidence will provide
insight into the possible effects of tea on the human gut microbiota, and even on the
viruses responsible for SARS-CoV-2. A beverage such as this may favor beneficial gut
microbes, which may have important implications due to the influence of gut microbiota on human health
... We have previously reported that 5-, 7-, and 10-component MIS significantly reduced body weight and fat mass, and improved markers of in vivo metabolism in a murine model [52]. Notably, green tea catechins (particularly epigallocatechin-3-gallate) [96] have been well-documented to facilitate a reduction in body weight and body fat tissue in humans over a similar experimental period [97][98][99][100][101]. Mechanistically, green tea (and/or its extracts) may alter SNS activation and lipolysis [102,103], downregulate fatty acid synthase [104], and induce thermogenesis [105]. ...
Background:
Despite the growing recognition of the obesity crisis, its rates continue to rise. The current first-line therapies, such as dietary changes, energy restriction, and physical activity, are typically met with poor adherence. Novel nutritional interventions can address the root causes of obesity, including mitochondrial dysfunction, and facilitate weight loss.
Objective:
The objective of this study was to investigate the effects of a multi-ingredient nutritional supplement designed to facilitate mitochondrial function and metabolic health outcomes over a 12 wk period.
Methods:
Fifty-five overweight and/or obese participants (age (mean ± SEM): 26 ± 1; body mass index (BMI) (kg/m2): 30.5 ± 0.6) completed this double-blind, placebo-controlled clinical trial. Participants were randomized to 12 wks of daily consumption of multi-ingredient supplement (MIS; n = 28; containing 50 mg forskolin, 500 mg green coffee bean extract, 500 mg green tea extract, 500 mg beet root extract, 400 mg α-lipoic acid, 200 IU vitamin E, and 200 mg CoQ10) or control placebo (PLA, n = 27; containing microcrystalline cellulose) matched in appearance. The co-primary outcomes were bodyweight and fat mass (kg) changes. The secondary outcomes included other body composition measures, plasma markers of obesity, fatty liver disease biomarkers, resting energy metabolism, blood pressure, physical performance, and quality of life. The post-intervention differences between MIS and PLA were examined via ANCOVA which was adjusted for the respective pre-intervention variables.
Results:
After adjustment for pre-intervention data, there was a significant difference in weight (p < 0.001) and fat mass (p < 0.001) post-intervention between the PLA and MIS treatment arms. Post-intervention weight and fat mass were significantly lower in MIS. Significant post-intervention differences corrected for baseline were found in markers of clinical biochemistry (AST, p = 0.017; ALT, p = 0.008), molecular metabolism (GDF15, p = 0.028), and extracellular vesicle-associated miRNA species miR-122 and miR-34a in MIS (p < 0.05).
Conclusions:
Following the 12 wks of MIS supplementation, weight and body composition significantly improved, concomitant with improvements in molecular markers of liver health and metabolism.
... Polyphenols can oxidize lipids and therefore reduce the concentrations of lipids in the serum of rats [44][45][46]. Polyphenols can also reduce the concentration of iron within tissues via either coordination or interference with some medications that reduce the bioavailability of iron [47,48]. In addition, polyphenols within tea can lead to an increase in the level of aluminum [49]. ...
... Catechin is a bioactive compound found in tea, and the healthpromoting effects associated with the consumption of tea are attributed to catechin [74]. Human studies have revealed that catechin consumption demonstrates several health benefits, including increased whole-body energy expenditure, fat oxidation [75], elevated non-shivering thermogenesis potential [76] and reduction in body fat [77]. A few human studies have also evaluated the effect of long-term catechin ingestion in relation to BAT metabolism. ...
Brown adipose tissue (BAT) is a thermogenic organ contributing to non-shivering thermogenesis. BAT becomes active under cold stress via sympathetic nervous system activation. However, recent evidence has suggested that BAT may also be active at thermoneutrality and in a postprandial state. BAT has superior energy dissipation capacity compared to white adipose tissue (WAT) and muscles. Thus, it has been proposed that the recruitment and activation of additional BAT may increase the overall energy-expending capacity in humans, potentially improving current whole-body weight management strategies. Nutrition plays a central role in obesity and weight management. Thus, this review discusses human studies describing BAT hyper-metabolism after dietary interventions. Nutritional agents that can potentially recruit brown adipocytes via the process of BAT-WAT transdifferentiation are also discussed.
... Scientists found that green tea extracts boost energy expenditure in mice via stimulating brown fat thermogenesis [96]. Tea catechins seem to have an anti-obesity effect in mice fed a HFD and stimulated lipid catabolism in the liver [125,126]. In mice, dietary EGCG attenuated diet-induced body fat storage [127]. ...
Obesity is a growing health concern in today’s society. Current estimates indicate that obesity occurs in both adults and young people. Recent research also found that the Hispanic population in the U.S. is 1.9 times more likely to be overweight as compared to their non-Hispanic population. Obesity is a multifactorial disease that has a variety of causes. All current treatment options incorporate dietary changes aimed at establishing a negative energy balance. According to current scientific research, multiple factors are involved with the development of obesity, including genetic, biochemical, psychological, environmental, behavioral, and socio-demographic factors. The people who suffer from obesity are far more likely to suffer serious health problems, such as stroke, diabetes, lung disease, bone and joint disease, cancer, heart disease, neurological disorders, and poor mental health. Studies indicate that multiple cellular changes are implicated in the progression of obesity, mitochondrial dysfunction, deregulated microRNAs, inflammatory changes, hormonal deregulation, and others. This article highlights the role that oxidative stress plays in obesity and current obesity-prevention techniques with an emphasis on the impact of catechins to prevent and treat obesity.
... The chemical composition of tea includes proteins, polysaccharides, polyphenols (cathecins or flavan-3-ols, theaflavins, thearubigins, and proanthocyanidins), chlorophyll, minerals, and trace elements volatile compounds, amino and organic acids, lignins and alkaloid (Chen et al., 2009). Tea is wellknown for it health benefits because of its poliphenol bioactive content, especially chatechin which have antioxidants activity that play a role in reducing the free radical effect (Vecchia et al., 1992;Bravo et al., 1998;Nagao et al., 2005). Catechin belong to flavonoid that posses the high antioxidant activity in biological system. ...
!--[if gte mso 9]> <!--[if gte mso 9]> Degenerative diseases and chronic diseases are often caused by oxidative stress . Oxidative stress caused by free radicals. Antixodant as inhibitor are needed t o prevent it which is one of antioxidant sources is tea. Tea processing generally produce various kinds of teas such as black, green and oolong tea. Tea processing affect the content of phenoli c compounds . The aim of the research is to evaluate phytochemical content, total phenolic conten t of black tea , green tea and oolong tea extracts using catechin, quercetin , kaempferol, myricetin as standard, and to evaluate the antioxidative potency of black tea, green tea and oolong tea extracts compared to catechin, quercetin , kaempferol, myricetin . Phytochemical assay using modified Farnsworth method, the antioxidant activity were measured by by its 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity. Green tea extract contained highest phenolic and flavonoid. The highest antioxidant activity was green tea extract with IC50 =0,487 μ g/mL . Green tea extract content phenol and flavonoid are higher compared to the other extracts, green tea extract has the highest antioxidant activity. </p
... When the generation of free radicals exceeds the body's antioxidant level, lipid peroxidation occurs, which can be estimated from the level of MDA, which is a reliable sign of the degree of lipid peroxidation. Polyunsaturated fatty acids such as linolenic acid act as a protective constituent against lipid peroxidation by increasing the cellular antioxidants level 32 . MDA level was significantly (P < 0.05) increased in OS, and I rats, while this level gradually decreased when the rats received TO. ...
The present study has been conducted to search out the anti-oxidative and anti-inflammatory potential of leaves of Camellia sinensis L. oil (Tea oil, TO). Forty-eight rats were included for 14 days experiment namely: Group I was normal to control, Group II was vehicle control, and Group III to VIII rats were subjected to paracetamol at the dose of 15 mg/ kg body weight/day to induce oxidative stress and inflammation (OS and I rats). Group IV to VII rats orally received TO at the dose of 100, 200, 400, 800 mg/kg, respectively and Group VIII received olive oil at 400 mg/kg. Paracetamol causes a significant (p < 0.05) increase in plasma urea, creatinine, glutamine-oxalic-transaminase, glutamate-pyruvate-transaminase, alkaline-phosphatase, interleukin-18 and tissue-injury-molecule-1, malondialdehyde and degeneration of hepatic cells in case of only OS and I rats. But treatment with TO in different doses showed a significant (p < 0.05) decrease above said parameters. We observed a significant (p < 0.05) decrease in superoxide dismutase, catalase, interleukin-10 levels in OS and I rats and also treatment with TO showed a significant (p < 0.05) increase in superoxide dismutase, catalase, interleukin-10 level in group IV to VII compared with only group III rats. Tea oil shows potent antioxidative activities against high-dose paracetamol-induced oxidative stress and inflammation by regulating the levels of pro-inflammatory and anti-inflammatory cytokines, whereas the most effective dose TO was 400 mg/kg.
... These conflicting results in the response to caffein may be explained by differences in doses and duration of the studies. Several studies have investigated if the thermogenic activity induced by catechins and caffein is able to counteract fat expansion and body weight gain in humans, and a meta-analysis performed by Phung et al. shows that intake of catechins and caffein, compared with caffein alone, is more efficient in reducing BMI, body weight and waist circumference, suggesting that catechins and caffein synergize in regulating body fat mass [77][78][79][80]. ...
Obesity and its associated comorbidities have become pandemic, and challenge the global healthcare system. Lifestyle changes, nutritional interventions and phamaceuticals should be differently combined in a personalized strategy to tackle such a public health burden. Altered brown adipose tissue (BAT) function contributes to the pathophysiology of obesity and glucose metabolism dysfunctions. BAT thermogenic activity burns glucose and fatty acids to produce heat through uncoupled respiration, and can dissipate the excessive calorie intake, reduce glycemia and circulate fatty acids released from white adipose tissue. Thus, BAT activity is expected to contribute to whole body energy homeostasis and protect against obesity, diabetes and alterations in lipid profile. To date, pharmacological therapies aimed at activating brown fat have failed in clinical trials, due to cardiovascular side effects or scarce efficacy. On the other hand, several studies have identified plant-derived chemical compounds capable of stimulating BAT thermogenesis in animal models, suggesting the translational applications of dietary supplements to fight adipose tissue dysfunctions. This review describes several nutraceuticals with thermogenic properties and provides indications, at a molecular level, of the regulation of the adipocyte thermogenesis by the mentioned phytochemicals.
... Nagao et al. [18] realizaram uma pesquisa com homens trabalhadores japoneses saudáveis para investigar o efeito das catequinas do chá verde na redução de gordura corporal e a relação entre LDL oxidada e variáveis de lipídeo corporal. Para isso, os homens participantes foram divididos em dois grupos com Índice de Massa Corporal (IMC) e circunferência da cintura (CC) semelhantes e a um grupo foi administrada uma dieta balanceada e uma garrafa de chá (340 ml) contendo 690 mg de catequinas e o grupo controle que recebeu uma dieta balanceada e uma garrafa (340 ml) de chá contendo apenas 22 mg de catequinas durante doze semanas. ...
O chá verde é uma das bebidas mais populares no mundo não só pelo seu sabor e aroma agradáveis, mas também pelos seus efeitos benéficos í saúde. A sua composição química e seu alto teor em polifenóis estão associados ao tratamento da obesidade, dislipidemias, doenças cardiovasculares, diabetes e câncer. O objetivo desse trabalho foi apresentar as propriedades funcionais do chá verde na saúde humana por meio da revisão de literatura sobre o chá verde e seus compostos bioativos relacionados í saúde humana e a capacidade de modificar mecanismos bioquímicos e fisiológicos. Observou-se como resultado que o chá verde pode ser uma ferramenta do nutricionista no controle da obesidade bem como outras doenças correlacionadas, auxiliando no tratamento dietético, embora sejam necessários mais estudos para definição da quantidade necessária para obtenção dos seus benefícios.Palavras-chave: chá verde, polifenóis, catequinas, Camellia sinensis.
Background:
In this systematic review and meta-analysis, the impact of green tea supplementation on measurement/indices of adiposity was investigated.
Methods:
Using predefined keywords, online databases (PubMed, Scopus, Web of Science Core Collection, and Google Scholar) were searched for relevant studies, published from inception up to February 2024. Data were extracted and registered. Subgroup analyses and the investigation of linear and non-linear associations were carried out.
Results:
Green tea supplementation reduced BW (WMD: -0.74 kg; 95% CI: -0.97, -0.51), BMI (WMD: -0.29 kg/m2; 95% CI: -0.38, -0.19), WC (WMD: -1.04 cm; 95% CI: -1.55, -0.53), BFP (WMD: -0.65%; 95% CI: -1.03, -0.27), and leptin (WMD: -0.92 ng/ml; 95% CI: -1.71, -0.14), but did not change adiponectin levels (WMD: 0.20 µg/ml; 95% CI: -0.17, 0.57).
Conclusion:
Supplementation with green tea seems to be effective in reducing excess adiposity.
Functional nutrition plays a critical role in maximizing athletic performance by adapting dietary strategies to meet the unique physiological needs of athletes. This approach goes beyond general nutritional guidelines and focuses on optimizing digestion, nutrient absorption and energy utilization to support endurance, strength, recovery, and overall health. By integrating whole foods, targeted supplements, and personalized diet plans, functional nutrition helps athletes achieve peak performance, reduce injury risk, and maintain long-term health. This chapter reviews key functional nutrition strategies such as macronutrient balance, micronutrient supplementation, and the timing of nutrient intake necessary to enhance athletic output.
Obesity is a public health crisis that has reached epidemic proportions worldwide, demanding urgent attention. To combat obesity, people endeavor to follow a healthy diet and regularly engage in physical activities. However, maintaining a healthy diet and physical activity is challenging, highlighting the need for novel effective therapies. This review aims to evaluate the therapeutic efficacy and safety of a well-researched functional food ingredient, green tea extract, for combating obesity. To assess the effectiveness of green tea extract, the review systematically examines various obesity indicators. It focuses on markers for body fat reduction in rodent models and humans, including weight, BMI, body fat percentage, and waist circumference. Furthermore, it explores the potential for suppressing and preventing obesity-related metabolic disorders. By thoroughly examining the effectiveness and mechanism of green tea extract, the study seeks to understand the potential of green tea extract as a nutraceutical/functional food for obesity management and prevention.
Background
The prevalence of obesity and its related ailments is on the rise, posing a substantial challenge to public health. Tea, widely enjoyed for its flavors, has shown notable potential in mitigating obesity. Yet, there remains a lack of exhaustive bibliometric studies in this domain.
Methods
We retrieved and analyzed multidimensional data concerning tea and obesity studies from January 2004 to June 2024, using the Web of Science Core Collection database. This bibliometric investigation utilized tools such as Bibliometrix, CiteSpace, and VOSviewer to gather and analyze data concerning geographical distribution, leading institutions, prolific authors, impactful journals, citation patterns, and prevalent keywords.
Results
There has been a significant surge in publications relevant to this field within the last two decades. Notably, China, Hunan Agricultural University, and the journal Food and Function have emerged as leading contributors in terms of country, institution, and publication medium, respectively. Zhonghua Liu of Hunan Agricultural University has the distinction of most publications, whereas Joshua D. Lambert of The State University of New Jersey is the most cited author. Analyses of co-citations and frequently used keywords have identified critical focus areas within tea anti-obesity research. Current studies are primarily aimed at understanding the roles of tea components in regulating gut microbiota, boosting fat oxidation, and increasing metabolic rate. The research trajectory has progressed from preliminary mechanism studies and clinical trials to more sophisticated investigations into the mechanisms, particularly focusing on tea’s regulatory effects on gut microbiota.
Conclusion
This study offers an intricate overview of the prevailing conditions, principal focus areas, and developmental trends in the research of tea’s role against obesity. It delivers a comprehensive summary and discourse on the recent progress in this field, emphasizing the study’s core findings and pivotal insights. Highlighting tea’s efficacy in obesity prevention and treatment, this study also points out the critical need for continued research in this area.
Background and aim: Physical training accompanied with herbal supplement consumption is one of the proposed methods for controlling obesity and its complications, such as diabetes. The purpose of this study was to investigate the effect of an 8-week aerobic exercise program and supplementation with green tea on HSP72 and BMI in obese women with type 2 diabetes.
Methods: In the present semi-experimental study, thirty-five obese women with diabetes (BMI ≥30) with an average age of 60-45 years, were randomly assigned into four groups: green tea (n=9), aerobic exercise with green tea (n=9), aerobic exercise (n=9) and control (n=8).The participants of supplementation groups received 1500 mg capsules of green tea extract daily for 8 weeks. Moreover, the control groups were given capsules containing roasted wheat flour. Exercises training were performed for 8 weeks, 3 sessions per week for 50 minutes per session, with an intensity of 75-60% of maximum heart rate. For statistical analysis, One Way Analysis Variance (ANOVA) with post hoc Tukey t-tests were used.
Results: The results showed that the weight (p=0.000*), body mass index (p=0.000*) and glucose (p=0.064*) were significantly reduced. Furthermore, HSP72 levels were significantly increased in the experimental groups (green tea, green tea, exercise, practice) (p=0.000*), while this difference was not significant in the control group. The consumption of green tea extract had a significant effect in controlling the HSP 72 levels, weight and BMI in the green tea group (P < 0.05).
Conclusion: It appeared that consuming green tea supplementation with aerobic exercise can influence and control obesity and increase of HSP72 of type 2 diabetes patients due to weight loss and BMI reduction.
Background
Obesity is reaching epidemic proportions with 51% of the population expected to be obese by 2030. Recently, polyphenols have been highlighted as an effective approach to managing obesity and associated risks. Polyphenols are a large class of bioactive plant compounds classified into two major categories: flavonoids which are distinguished by the fundamental C6-C3-C6 skeleton and non-flavonoids.
Objective
This systematic review evaluated the effect of different polyphenol sources in overweight and obese people with and without type 2 diabetes. The primary outcome was lipid profile and the secondary outcomes were blood glucose, HbA1c (%), HOMA-IR, weight, and body mass index.
Method
A search was undertaken in PubMed, Web of Science, Medline, and Wiley for randomized control trials that assessed different sources of polyphenols in overweight and obese people with or without type 2 diabetes. The quality of the included studies was assessed using the National Heart, Lung, and Blood Institute Quality Assessment Tool.
Result
The search yielded 935 studies, of which six randomized control trials met the inclusion criteria. Five studies found no significant difference in lipid profile between the control and intervention groups in triglycerides, total cholesterol, LDL cholesterol, and HDL cholesterol. However, one study showed significant differences in triglycerides (p = 0.04) and HDL cholesterol (p = 0.05) between the two groups with no significant difference in total cholesterol and LDL cholesterol. There were no significant changes in blood glucose observed in the included studies, with only two studies reporting a significant difference in A1c between the groups. Four studies found no difference in HOMA-IR, while one study showed a significant decrease in HOMA-IR in the intervention group compared to the control group. Three studies reported no difference in BMI or weight between the two groups.
Conclusion
The data associated with the specific health benefits of polyphenols and their sources in people with overweight, obese, and type 2 diabetes are still limited, so further research is required to support their use and prove their benefits.
There has been a rise in popularity of “stimulant-free” or caffeine-free fat loss supplements, but it is not well understood whether those fat loss supplements are effective at enhancing thermogenesis without caffeine’s influence. The purpose of this study was to examine the effects of a caffeinated and non-caffeinated commercially available fat loss supplement on resting energy expenditure (REE), hunger, and hemodynamic variables in healthy adults. Twenty-five healthy male and female participants completed three separate laboratory visits after overnight fasts. Baseline assessments of REE, subjective hunger, heart rate (HR), and blood pressure (BP) were followed by ingestion of a caffeinated (Phoenix, Legion®; CAF), non-caffeinated (Phoenix Caffeine-Free, Legion®; NCAF), or placebo (PL) fat loss supplement. REE, hunger, HR, and BP assessments were repeated at 60-, 120-, and 180-min post-ingestion. CAF, but not NCAF, significantly elevated REE greater than PL at all time points (p < 0.05). NCAF significantly reduced hunger compared to CAF and PL at the 120-min time point (p = 0.006). CAF significantly increased diastolic BP 60-min post-ingestion and significantly increased systolic BP 120- and 180-min post-ingestion compared to NCAF and PL. Further research is warranted with respect to investigating non-caffeinated ingredients and their effects on REE.
Besin, Antioksidan, Takviye, Performans, Egzersiz
Background: Regular exercise activity along with the consumption of green tea and green coffee has anti diabetic, anti-inflammatory, anti-fibrotic, and anti-obesity properties in addition to antioxidant compounds. This study aims to investigate the effect of eight weeks of progressive aerobic activity along with the consumption of green tea and green coffee on fat oxidation and blood pressure in overweight girls.
Methods: This research was carried out using a semi experimental method and a clinical trial in the form of pretest and post-test. Based on this, 48 people were invited to participate in the briefing session and randomly divided into four exercise groups + green coffee, 12 people (Exe+coffee), exercise group + green tea, 12 people (Exe+tea), exercise group + Green coffee+green tea, 12 people (Exe+coffee+tea) and training group, 12 people (Exe). One day after taking blood in the first stage and measuring physical and physiological indicators in all four groups, the subjects received progressive aerobic training for eight weeks, as well as green tea or green coffee or both depending on the experimental group.
Findings: The results of the present study showed that there is no significant difference in the variables of systolic blood pressure, diastolic blood pressure, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol between the four groups, but in the variables of body weight, body mass index, body fat percentage, waist to hip ratio and Triglyceride, the differences between the four groups were significant.
Conclusion: Obese and overweight women can improve their body composition and general health by combining progressive aerobic exercises and consuming green tea and green coffee supplements.
Keywords: Obesity; Body mass index; Weight management; Physical activity
17 / 12 / 90 ﻣﻘﺎﻟﻪ: ﭘﺬﯾﺮش ﺗﺎرﯾﺦ 11 / 9 / 91 ﭼ ﮑ ﯿ ﺪه ﻫﺪف : واﮐﻨﺸـﯽ ﭘـﺮوﺗﺌﯿﻦ ﺷـﺎﻣﻞ ﻋﺮوﻗـﯽ ﻗﻠﺒﯽ ﺧﻄﺮزاي ﻋﻮاﻣﻞ ﺑﺮﺧﯽ ﺑﺮ ﺳﺒﺰ ﭼﺎي ﻣﮑﻤﻞ و ﻫﻮازي ﺗﻤﺮﯾﻨﺎت ﺗﺎﺛﯿﺮ ﺑﺮرﺳﯽ C ، LDL ، HDL ، و ﺗﺎم ﮐﻠﺴﺘﺮول ﺗﺮي ﮔﻠﯿﺴﺮﯾﺪ ﺑﻮد. وزن اﺿﺎﻓﻪ داراي ﻣﺮدان در ﺳﺮﻣﯽ روش ﻫﺎ : 43 ﻣﺮد داراي اﺿـﺎﻓﻪ وزن داوﻃﻠـﺐ ﺷـﺪﻧﺪ و در ﭼﻬـﺎرﮔﺮوه ﮐﻨﺘﺮل، ﻣﮑﻤﻞ ﭼﺎي ﺳ ﻣﺪت ﺑﻪ ﺗﻤﺮﯾﻦ ﮔﺮوه ﮔﺮﻓﺘﻨﺪ. ﻗﺮار ﺳﺒﺰ ﭼﺎي ﻣﮑﻤﻞ و ﻫﻮازي ﺗﻤﺮﯾﻦ ﺗﺮﮐﯿﺐ و ﻫﻮازي، ﺗﻤﺮﯾﻦ ﺒﺰ، 10 در ﺑﺎر )ﺳﻪ ﻫﻔﺘﻪ ﺷﺪت ﺑﺎ ﻫﻮازي ﺗﻤﺮﯾﻨﺎت ﺑﻪ ﻫﻔﺘﻪ( 75-65 ﭘﺮداﺧﺘﻨﺪ. ﻗﻠﺐ ﺿﺮﺑﺎن ﺣﺪاﮐﺜﺮ درﺻﺪ ﮔﺮوه ﭼﺎي ﺳﺒﺰ روزاﻧﻪ ﺳﻪ ﻋﺪد ﭼﺎي ﺳﺒﺰ ﮐﯿﺴﻪ اي ﻣﺤﺘﻮي دو ﮔﺮم ﭼﺎي ﺧﺸﮏ در ﺳﻪ وﻋﺪه ﻏﺬاﯾﯽ، ﻣ از ﺑﻌـﺪ و ﻗﺒـﻞ ﮔﺮﻓـﺖ. ﺻﻮرت ﻣﺪاﺧﻠﻪ دو ﻫﺮ ﺳﺒﺰ ﭼﺎي و ﺗﻤﺮﯾﻦ ﺗﺮﮐﯿﺐ ﮔﺮوه ﺑﺮاي ﮐﺮدﻧﺪ. ﺼﺮف آزﻣﻮدﻧﯽ ﻫﻤﻪ از ﺗﺤﻘﯿﻖ، دوره آﻣﺪ. ﻋﻤﻞ ﺑﻪ ﺧﻮﻧﮕﯿﺮي ﻧﺎﺷﺘﺎﯾﯽ وﺿﻌﯿﺖ در ﻫﺎ داده و ﻃﺮﻓـﻪ ﯾـﮏ وارﯾـﺎﻧﺲ آﻧﺎﻟﯿﺰ آزﻣﻮن از اﺳﺘﻔﺎده ﺑﺎ ﻫﺎ آﻧـﺎﻟﯿﺰ ﺷﺪﻧﺪ. ﺗﺤﻠﯿﻞ ﮐﻮوارﯾﺎﻧﺲ ﻧﺘﺎﯾﺞ ﺗﻐﯿﯿـﺮ ﺳـﺒﺰ، ﭼـﺎي ﻣﺼﺮف و ﻫﻮازي ﺗﻤﺮﯾﻨﺎت ﺗﺮﮐﯿﺐ و ﺳﺒﺰ ﭼﺎي ﻣﺼﺮف ﻫﻮازي، ﺗﻤﺮﯾﻨﺎت داد ﻧﺸﺎن ﻧﺘﺎﯾﺞ : واﮐﻨﺸﯽ ﭘﺮوﺗﺌﯿﻦ ﻣﯿﺰان در ﻣﻌﻨﺎداري C ﻧﻤﯽ اﯾﺠﺎد ﻟﯿﭙﯿﺪي رخ ﻧﯿﻢ و ﮐﻨﺪ) 05 / 0 P> (ﺷـﺎﺧﺺ و وزن ﻣﻌﻨﺎدار ﮐﺎﻫﺶ ﺑﺎﻋﺚ ﺳﺒﺰ ﭼﺎي ﻣﺼﺮف. ﮔﺮدﯾﺪ ﺑﺪن ﺗﻮده) 05 / 0 < P) ﺷﺪ ﺑﺪن ﭼﺮﺑﯽ درﺻﺪ و ﺑﺪن ﺗﻮده ﺷﺎﺧﺺ وزن، ﻣﻌﻨﺎدار ﮐﺎﻫﺶ ﺑﺎﻋﺚ ﻫﻮازي ﺗﻤﺮﯾﻦ .(05 / 0 < P ﺗﻤﺮﯾﻦ ﺗﺮﮐﯿﺐ .(ﺷـﺪ ﺑـﺪن ﭼﺮﺑـﯽ درﺻـﺪ و ﺑـﺪن ﺗـﻮده ﺷـﺎﺧﺺ وزن، ﻣﻌﻨـﺎدار ﮐﺎﻫﺶ و ﻣﺼﺮﻓﯽ اﮐﺴﯿﮋن ﺣﺪاﮐﺜﺮ ﻣﻌﻨﺎدار اﻓﺰاﯾﺶ ﺑﺎﻋﺚ ﺳﺒﺰ ﭼﺎي و ﻫﻮازي) 05 / 0 < P ﮐﺎﻫ ﺑﺮ ﻫﻮازي ﺗﻤﺮﯾﻦ و ﺳﺒﺰ ﭼﺎي اﺛﺮ ﺑﯿﻦ .(ﻧﺪاﺷـﺖ وﺟﻮد ﻣﻌﻨﺎداري ﺗﻔﺎوت ﺑﺪن ﺗﻮده ﺷﺎﺧﺺ و وزن ﺶ) 05 / 0 P>
The impact of phytochemicals, as green tea catechins, on body composition measures has become a relevant topic as ongoing epidemiological evidence suggests their potential role in weight loss. Although catechins have been shown to modulate fat and energy metabolism, clinical effects of green tea consumption still remain controversial. Given the role played by physical exercise in weight management, it is important to determine whether the association of catechins and exercise is able to improve outcomes over and above the beneficial effects of exercise alone. Considering that scientific findings on this topic are not entirely consistent, aim of the present review was to assess the current scientific literature regarding the interplay between green tea catechins and exercise in overweight and obese populations. In particular, it was evaluated whether the addition of green tea supplementation to exercise training was able to further improve the exercise‐induced changes in body composition parameters.
This chapter discusses Microbial Metabolism of Polyphenols and Health
Three lines of evidence are presented that low density lipoproteins gently extracted from human and rabbit atherosclerotic lesions (lesion LDL) greatly resembles LDL that has been oxidatively modified in vitro. First, lesion LDL showed many of the physical and chemical properties of oxidized LDL, properties that differ from those of plasma LDL: higher electrophoretic mobility, a higher density, higher free cholesterol content, and a higher proportion of sphingomyelin and lysophosphatidylcholine in the phospholipid fraction. A number of lower molecular weight fragments of apo B were found in lesion LDL, similar to in vitro oxidized LDL. Second, both the intact apo B and some of the apo B fragments of lesion LDL reacted in Western blots with antisera that recognize malondialdehyde-conjugated lysine and 4-hydroxynonenal lysine adducts, both of which are found in oxidized LDL; plasma LDL and LDL from normal human intima showed no such reactivity. Third, lesion LDL shared biological properties with oxidized LDL: compared with plasma LDL, lesion LDL produced much greater stimulation of cholesterol esterification and was degraded more rapidly by macrophages. Degradation of radiolabeled lesion LDL was competitively inhibited by unlabeled lesion LDL, by LDL oxidized with copper, by polyinosinic acid and by malondialdehyde-LDL, but not by native LDL, indicating uptake by the scavenger receptor(s). Finally, lesion LDL (but not normal intimal LDL or plasma LDL) was chemotactic for monocytes, as is oxidized LDL. These studies provide strong evidence that atherosclerotic lesions, both in man and in rabbit, contain oxidatively modified LDL.
We have developed a new method of measuring fat volume of the human body, using computed tomographic scanning (CT scan) - no ideal or direct method has been available for this calculation. In our study a human body is divided into 11 cylindrical shapes, ie a head, a chest, an abdomen, both sides of forearms, upper arms, thighs and calves to be subjected to the measurement. Eleven computed tomographic sections were examined at the middle point of each segment to obtain the areas of fat tissue. Volume of each cylindrical segment was calculated by multiplying a cross-sectional area of fat tissue by the height of each part. Then the volume of fat tissue of the whole body was determined by the sum of fat tissue volume of eleven parts (as above). By this method, nine massive obese subjects with 147-188 percent of ideal body weight were found to possess fat tissue occupying 30-63 percent of total body volume. We also found female obese patients had a significantly higher percentage of fat tissue than male obese patients when they had same degree of obesity. In addition to the study above, we examined 18 control and 19 obese subjects and measured subcutaneous fat, muscle plus bone and visceral fat separately by CT scan at the umbilicus level. In obese subjects, increased abdominal fatty mass was mainly due to the accumulation of subcutaneous fat, although substantial increase of visceral fatty mass was demonstrated in a few cases.
The murine monoclonal antibody mAb-1H11 raised against malondialdehyde (MDA)-modified LDL, was used to detect cross-reacting material in human atheromatous tissue and in plasma. MDA-modified LDL levels in plasma were 0.19 +/- 0.02 mg/dl (mean +/- SEM) in 44 control subjects, 0.24 +/- 0.02 mg/dl in 15 patients with chronic stable angina pectoris (P = NS vs LDL cholesterol matched controls), 1.4 +/- 0.1 mg/dl in 60 patients with acute myocardial infarction (P < 0.001 vs controls), and 0.86 +/- 0.11 mg/dl in 22 patients with carotid atherosclerosis (P < 0.001 vs controls). Modified LDL, isolated from pooled LDL of 10 patients, showed a higher electrophoretic mobility on agarose gels, a higher content of thiobarbituric acid reactive substances, and a higher cholesterol/protein ratio than native LDL and had a similar reactivity (antigen/protein ratio) in the assay as the in vitro MDA-modified LDL used for calibration. Its apo B-100 moiety was not fragmented. Uptake of this modified LDL by macrophages resulted in foam cell generation. In conclusion, elevated plasma levels of atherogenic MDA-modified LDL may be a marker for unstable atherosclerotic cardiovascular disease.
In aged mice, the redox-regulated transcription factor nuclear factor-kappaB (NF-kappaB) becomes constitutively active in many tissues, as well as in cells of the hematopoietic system. This oxidative stress-induced activity promotes the production of a number of pro-inflammatory cytokines, which can contribute to the pathology of many disease states associated with aging. The administration to aged mice of agents capable of activating the alpha isoform of the peroxisome proliferator-activated receptor (PPARalpha) was found to restore the cellular redox balance, evidenced by a lowering of tissue lipid peroxidation, an elimination of constitutively active NF-kappaB, and a loss in spontaneous inflammatory cytokine production. Aged animals bearing a null mutation in PPARalpha failed to elicit these changes following treatment with PPARalpha activators, but remained responsive to vitamin E supplementation. Aged C57BL/6 mice were found to express reduced transcript levels of PPARalpha and the peroxisome-associated genes acyl-CoA oxidase and catalase. Supplementation of these aged mice with PPARalpha activators or with vitamin E caused elevations in these transcripts to levels seen in young animals. Our results suggest that PPARalpha and the genes under its control play a role in the evolution of oxidative stress excesses observed in aging.
The health risks of obesity increase with its severity and reach significance at a weight > 20% above optimal, by using life insurance tables, or at a body mass index > 27. Risks include hypertension, insulin resistance and diabetes mellitus, cardiovascular disease, hypertriglyceridemia, low high-density-lipoprotein cholesterol, and, in some studies, high totaland low-density-lipoprotein cholesterol. There is an increased mortality from endometrial cancer in women and from colorectal cancer in men. Chronic hypoxia and hypercapnia, sleep apnea, gout, and degenerative joint disease can occur with more severe obesity. The distribution of body fat is directly related to these health risks. Abdominal obesity is more dangerous than gluteal-femoral obesity because the amount of intraabdominal fat seems to determine much of the increased peril; therefore, risks of cardiovascular disease, stroke, hypertension, and diabetes increase with abdominal obesity, even independently of total fat mass.
The term 'ion-selective electrodes' is applied to a range of membrane electrodes which respond selectively toward one (or several) ionic species in the presence of others. The less-preferred term 'ion-specific' is not favored1 because these electrodes are rarely specific in their response to one ionic species over others, although this is a desirable property sought by the designer of new electrodes. The description membrane is used here in its broadest sense to denote a thin section of electrically conducting material separating two solutions and across which a potential develops. Often the term membrane has associated with it the notion of permeability to a species present in the flanking solutions. However, although this is undoubtedly true with certain porous biological and synthetic membranes, the actual mechanism of electrical conduction in general varies with the type of membrane material; indeed it may change within it.
The influence of tea catechins on the absorption of starch or sucrose was investigated in vivo. Tea catechins were administered orally to rats before soluble starch or sucrose administration. Saccharide-dosed rats were killed and the blood and the contents of the intestine were collected at intervals over two hours. Catechins of certain concentrations suppressed the increase of plasma glucose levels, thus concurrently suppressing insulin activity. Increased activity of intestinal α-amylase by starch dosing was inhibited markedly in the catechin-administered rats. Sucrase on the brush border membrane was also inhibited by prior catechin administration. From these results it was assumed that orally administered catechins will inhibit intestinal α-amylase or sucrase, thereby deterring the digestion of certain amounts of starch or sucrose and eventually reducing the plasma glucose levels.
A(−)-epicatechin (EC) and (−)-epigallocatechin (EGC) mixture and a mixture of their gallates (ECG and EGCG, respectively) markedly lowered lymphatic cholesterol absorption in rats with a cannulated thoracic duct. A mixture of ECG and EGCG was more effective in reducing cholesterol absorption than the EC and EGC mixture. These catechins also tended to decrease lymphatic absorption of triacylglycerols, although not so pronounced as in cholesterol absorption. An in vitro study on micellar solubility of cholesterol showed that these catechin mixtures precipitated cholesterol solubilized in mixed bile salt micelles in a dose-dependent manner. A mixture of ECG and EGCG more effectively precipitated micellar cholesterol than a mixture of EC and EGC. When purified EC, EGC, ECG and EGCG were used, EGCG was more effective in precipitating micellar cholesterol than ECG. The effect of EC and EGC was comparable and weaker than their gallate esters. The bile acid concentration in the micelles was not affected by these catechins. A positive correlation was observed between the amount of coprecipitated EGCG and cholesterol. These results clearly show that tea catechins, in particular their gallate esters, effectively reduce cholesterol absorption from the intestine by reducing solubility of cholesterol in mixed micelles. The observation accounts for the hypocholesterolemic effect of tea catechins.
A simple, sensitive and reliable method is presented for the direct photometric measurement of inorganic phosphate in serum or urine. Reagents are stable, inexpensive and minimal in number. The phosphomolybdate complex formed in an acid medium is reduced by p-methylaminophenol sulfate ; subsequent alkalinization with monoethanolamine produces a clear blue color, which is read at 660 nm. Results compare favorably with the Goldenberg-Fernandez manual method, which requires prior serum deproteinization, and the Kessler automated method. Inter-run precision is ± 3% (2 C.V.%). Bilirubin interference is slight and minimal hemolysis can be tolerated. Elevated serum protein levels do not interfere with the method.
To investigate the absorption and metabolism of an anticarcinogenic tea catechin, (-)-epigallocatechin-3-gallate (EGCg), in rats, a newly developed chemiluminescence-detection high-performance liquid chromatography (CL-HPLC) method was employed and the EGCg concentrations in blood plasma, liver, brain, small intestinal mucosa and colon mucosa were determined before and after EGCg administration. The recovery of EGCg, extracted consecutively with ethyl acetate and methanol, was 86.1% from plasma and 64.5-74.2% from the tissue samples. The EGCg concentrations of plasma and tissue samples from the control rat (before EGCg administration) were all below the detection limit (< 0.002 nmol/mL, 0.002 nmol/g), but 60 min after a single oral administration of EGCg (500 mg/kg body weight), the levels increased, reaching 12.3 nmol/mL in plasma, 48.4 nmol/g in liver, 0.5 nmol/g in brain, 565 nmol/g in small intestinal mucosa and 68.6 nmol/g in colon mucosa. The EGCg levels found in the tissues corresponded to 0.0003-0.45% of ingested EGCg. The results indicate that tea catechin, EGCg, is absorbed from the digestive tract, with the intestinal mucosa the most enriched of the organelles. This may explain the potent antioxidant function of EGCg in inhibiting colon mucosal phospholipid hydroperoxidation in the prevention of rat colonic carcinogenesis.
This review summarizes available information on epidemiological and experimental data showing an association of tea consumption with cancer prevention. Studies showing cancer risk associated with tea consumption are also summarized. Tea is grown in about 30 countries and, next to water, is the most widely consumed beverage in the world. Experimental studies demonstrating the chemopreventive effects of tea have been conducted principally with green tea; limited studies have also assessed the usefulness of black tea. Majority of these studies have been carried out in skin tumor model system where consumption through drinking water of water extracts of tea or a polyphenolic fraction isolated from tea has been shown to afford protection against chemical carcinogen- or ultraviolet radiation-induced skin tumorigenesis. Tea consumption has also been shown to afford protection against chemical carcinogen-induced lung, forestomach, esophagus, duodenum, pancreas, liver, breast and colon carcinogenesis in specific bioassay models. Evidence has also accumulated showing that tea polyphenols prevent tumor promoter- and ultraviolet B-induced inflammatory responses in murine skin. The species and strains of animals, dose, route, frequency and duration of carcinogen administration, as well as types, route of administration and duration of tea or its polyphenolic component(s) treatment are described in detail. A brief description regarding mechanism(s) responsible for the broad chemopreventive effects of tea is provided. Epidemiologic studies, though inconclusive, in general suggest a possible preventive effect of tea consumption on human cancer. On the basis of available information, epidemiologic and experimental studies are ongoing to draw the possible relationship between tea consumption and cancer causation and prevention. Appropriate strategies for future clinical chemoprevention trials to translate animal data to human cancer risk are warranted.
Zahlreiche Flavonoide (I) werden auf ihre inhibierende Wirkung gegenüber Catechol- O-Methyltransferase untersucht und Beziehungen zwischen der Struktur und der Wirkung erörtert.
Tea is grown in about 30 countries but is consumed worldwide, although at greatly varying levels. It is the most widely consumed beverage aside from water with a per capita worldwide consumption of approximately 0.12 liter per year. Tea is manufactured in three basic forms. Green tea is prepared in such a way as to preclude the oxidation of green leaf polyphenols. During black tea production oxidation is promoted so that most of these substances are oxidized. Oolong tea is a partially oxidized product. Of the approximately 2.5 million metric tons of dried tea manufactured, only 20% is green tea and less than 2% is oolong tea. Green tea is consumed primarily in China, Japan, and a few countries in North Africa and the Middle East. Fresh tea leaf is unusually rich in the flavanol group of polyphenols known as catechins which may constitute up to 30% of the dry leaf weight. Other polyphenols include flavanols and their glycosides, and depsides such as chlorogenic acid, coumarylquinic acid, and one unique to tea, theogallin (3-galloylquinic acid). Caffeine is present at an average level of 3% along with very small amounts of the other common methylxanthines, theobromine and theophylline. The amino acid theanine (5-N-ethylglutamine) is also unique to tea. Tea accumulates aluminum and manganese. In addition to the normal complement of plant cell enzymes, tea leaf contains an active polyphenol oxidase which catalyzes the aerobic oxidation of the catechins when the leaf cell structure is disrupted during black tea manufacture. The various quinones produced by the enzymatic oxidations undergo condensation reactions which result in a series of compounds, including bisflavanols, theaflavins, epitheaflavic acids, and thearubigens, which impart the characteristic taste and color properties of black tea. Most of these compounds readily form complexes with caffeine. There is no tannic acid in tea. Thearubigens constitute the largest mass of the extractable matter in black tea but their composition is not well known. Proanthocyanidins make up part of the complex. Tea peroxidase may be involved in their generation. The catechin quinones also initiate the formation of many of the hundreds of volatile compounds found in the black tea aroma fraction. Green tea composition is very similar to that of the fresh leaf except for a few enzymatically catalyzed changes which occur extremely rapidly following plucking. New volatile substances are produced during the drying stage. Oolong tea is intermediate in composition between green and black teas.
Risk of cardiovascular events was determined over 24 years of surveillance in relation to general adiposity reflected by relative weight and by regional obesity estimated by skinfolds and waist girth per inch of height. Upper quintile values of relative weight, subscapular skinfolds and waist girth were each associated with increased risks of cardiovascular disease in both sexes. Risk of total cardiovascular events increased with the degree of regional, central or abdominal obesity. Mortality from cardiovascular disease was also increased. Increased relative weight and central obesity were both associated with increased risk factors including cholesterol, blood pressure, glucose and uric acid. Changes in weight were mirrored by changes in risk factors with linear trends over a 15 lb range of weight fluctuations. Subscapular skinfold and the ratio of subscapular-to-triceps skinfold, measures of central obesity, were in either sex also associated with an increased probability of coronary attacks in particular. The subscapular skinfold contributed to CHD risk independent of body mass index (BMI). Multivariate analyses taking all the risk factors into account indicate an independent effect of abdominal obesity on stroke, cardiac failure and cardiovascular and all-cause mortality in men. In women, only the subscapular-to-triceps skinfold ratio independently contributes to CHD, cardiovascular and all cause mortality. Regional obesity appears to be an independent contributor to cardiovascular disease at a given level of general adiposity, its effect only partially mediated through promotion of other known risk factors. These data suggest that cardiovascular disease is as closely linked to abdominal as to general adiposity.
In the course of our studies on the development of anti-plaque agents for prevention of dental caries, we investigated effects of some of tea preparations and their individual components on the glucan synthesis catalyzed by glucosyltransferase (GTF) from Streptococcus mutans. Extracts of green tea and black tea, and polyphenol mixtures showed appreciable inhibition in the synthesis of insoluble glucan. Among the components isolated from tea infusions, theaflavin and its mono- and digallates had potent inhibitory activities at concentrations of 1-10 mM against GTF. (+)-Catechin, (-)-epicatechin and their enantiomers had moderate inhibitory activities at these concentrations, while galloyl esters of (-)-epicatechin, (-)-epigallocatechin and (-)-gallocatechin had increased inhibitory activities.
The energy intake (EI) of 1312 overweight subjects was assessed using the research dietary history method. EI was positively associated with overweight--as expressed by the body mass index (BMI)--in both males and females. Such findings are at variance with earlier reports of low dietary intakes in the obese and of an inverse relationship between EI and BMI. This discrepancy could be related to the dietary-interviews method used and/or to differences in the degree of motivation of the obese subjects in the various studies. On the other hand, our results are consistent with the positive relationship between energy expenditure (EE) and BMI previously reported in the literature and with the expected EE of our subjects.
Effects of tea catechins (tannins) on lipid metabolism were studied in male weanling rats fed a 25% casein diet containing 15% lard and 1% cholesterol for 28 days. Crude tea catechins prepared from green tea powder were supplemented at a 1% and 2% of the lard-cholesterol diet. The addition of 2% tea catechins slightly depressed growth but at the 1% level was without effect. Tea catechins decreased plasma total cholesterol, cholesterol ester, total cholesterol--HDL-cholesterol (VIDL-+LDL-cholesterol) and atherogenic index (VLDL-+LDL-cholesterol/HDL-cholesterol). Hematocrit and plasma glucose were not altered by the addition of tea catechins. The liver weight, liver total lipids and cholesterol concentrations in rats fed the lard-cholesterol diet increased more than in the control rats, but the addition of tea catechins to the lard-cholesterol diet decreased those parameters. Tea catechin supplementation increased fecal excretion of total lipids and cholesterol. The results demonstrate that tea catechins exert a hypocholesterolemic effect in cholesterol-fed rats.
The effects of decaffeinated green tea on CBA mice have been contrasted with those of water during 3 to 5 months of exposure to various intensities of social stress. Intensity was modified by using different types of caging: Henry-Stephens complex population cages for maximum stress, open field population cages for intermediate levels, and siblings in standard mouse boxes for minimal stress. Two population densities were used: high, with 16 males and 16 females per population cage; and low, with approximately half this number. In three sets of experiments, 58 comparisons were made between body weight, blood pressure, pulse rate, scarring, blood urea nitrogen (BUN), adrenal and heart weights, plasma corticosterone, adult male mortality, and number of weanlings of those on decaffeinated green tea and matched groups on water. Twenty-five of the comparisons indicated less arousal with the decaffeinated green tea and in none was the water favored. Blood pressure fell from 150 to 133 mm Hg. These results support the proposal that the polyphenols (bioflavonoids) of tea may have a beneficial sedative action.
We developed a sensitive enzyme-linked immunosorbent assay (ELISA) for detection of malondialdehyde-modified low-density lipoprotein (MDA-LDL) in human serum. A monoclonal antibody against MDA-LDL (ML25) used in our method recognized not only MDA-LDL but also other MDA-modified proteins. However, MDA-LDL was able to be detected specifically by using a combination of ML25 and an antibody specific for apolipoprotein B (apo B) (AB16), which was conjugated with beta-galactosidase. Using this method, measurable amounts of MDA-LDL were detected in the sera of 40 healthy individuals. MDA-LDL was observed to be mainly distributed in the human LDL fraction separated by density gradient ultracentrifugation, while in each lipoprotein subfraction the largest amount of MDA-LDL per protein was found at a subfraction between LDL and HDL. The particle size of LDL in this fraction was smaller than that of LDL in the main LDL fraction, as assessed by electrophoresis. In addition, LDL oxidized by Cu2+ was also detectable with this method. We conclude that our method is sensitive and specific for MDA-LDL and might be useful for investigating MDA-LDL in the human circulation.
The antioxidative activity of theaflavins (TFs) and thearubigin (TR) purified from the infusion of black tea leaves was examined using the tert-butyl hydroperoxide-induced lipid peroxidation of rat liver homogenates. The concentrations which produced 50% inhibition of lipid peroxidation (IC50) by theaflavin (TF), theaflavin monogallate-A (TFM-A), and TR were 4.88 x 10(-4), 4.09 x 10(-4), and 4.95 x 10(-4%) (w/v), respectively. The anti-oxidative activity of these compounds was higher than that of glutathione, L(+)-ascorbic acid, dl-alpha-tocopherol, butylated hydroxytoluene, butyl hydroxyanisole, etc., but was lower than the activity of (-)-epicatechin gallate, (-)-epigallocatechin, and (-)-epigallocatechin gallate. As to the IC50 in molarity, the antioxidative activity of TFM-A was the second highest among all the samples used in this study. The antioxidative activity of lyophilized tea infusions was compared. The activity of black tea was about as potent as that of green tea. These results suggest that black tea infusion containing TFs and TR could inhibit lipid peroxidation in biological conditions in the same way as green tea infusion containing epicatechins.
(-)Epigallocatechin gallate (EGCg) and theaflavin digallate (TF3) (1-10 microM) inhibited the infectivity of both influenza A virus and influenza B virus in Madin-Darby canine kidney (MDCK) cells in vitro. Study by electron microscope revealed that EGCg and TF3 (1 mM) agglutinated influenza viruses as well as did antibody, and that they prevented the viruses from adsorbing to MDCK cells. EGCg and TF3 more weakly inhibited adsorption of the viruses to MDCK cells. EGCg and TF3 (1-16 microM) also inhibited haemagglutination by influenza viruses. These findings suggest that tea polyphenols bind to the haemagglutinin of influenza virus, inhibit its adsorption to MDCK cells, and thus block its infectivity.
The relative contributions of a low and high body mass index (BMI [weight in kilograms divided by height in meters squared]) to all-cause and cause-specific mortality are still controversial.
To examine mortality rates in relation to BMI in a prospective cohort study of 48,287 Dutch men and women aged 30 to 54 years at baseline from 1974 to 1980.
During an average 12-year follow-up, 1319 deaths occurred. Relative risks (RRs) were calculated from the Cox proportional hazard model by using a BMI between 18.5 and 24.9 kg/m2 as the reference category.
All-cause mortality was significantly increased in obese men (BMI, > or = 30 kg/m2; RR, 1.5; 95% confidence interval [CI], 1.1-2.0) and in underweight men (BMI, < 18.5 kg/m2; RR, 2.6; 95% CI, 1.8-3.9) but not in women. The increased risk in underweight men could be attributed to deaths within the first 5 years of follow-up and to lung cancer mortality among smokers. Coronary heart disease (CHD) mortality was about 3-fold higher among obese men and women. About 21% and 28% of CHD mortality in men and women, respectively, could be attributed to being overweight (BMI, > or = 25 kg/m2). The RR (but not the absolute risk) for CHD among obese men was still significant after adjustment for the presence of smoking, hypertension, hypercholesterolemia, and diabetes mellitus at baseline, and it was more pronounced for CHD among nonsmokers than among smokers (RR, 7.1; 95% CI, 2.3-21.7; and RR, 2.7; 95% CI, 1.5-4.7, respectively).
Total mortality was increased in obese and underweight men but not in women. The increased mortality in overweight men was mainly attributable to CHD and, in underweight men, to early mortality and especially lung cancer mortality among smokers.
To assess whether usual diet (especially intake of dietary fat, carbohydrate, and fiber) was related to body fat percentage in healthy men.
A written questionnaire provided data on demographic and lifestyle characteristics. Dietary fat, carbohydrate, protein, and fiber intakes were analyzed using the National Cancer Institute food frequency questionnaire. Percentage of body fat was determined using three-site skinfold measurements, and a submaximal treadmill test was used to estimate aerobic fitness.
Subjects were 203 healthy men (14.0 +/- 5.3% mean body fat) aged 21 to 71 years. The subjects were chosen from randomly selected districts within Utah County and volunteered for free diet and fitness evaluations.
Multiple regression analysis determined the extent to which the individual diet components predicted body composition before and after controlling for energy intake, fitness level, body weight, and age. Multivariate analysis of variance was used to compare relative body fat groups in regard to dietary variables.
Reported intakes of carbohydrate (P = .0085, R2 = .022), complex carbohydrate (P = .0127, R2 = .024), and fiber (P = .002, R2 = .03) were inversely associated with body fat after controlling for age, energy intake, and fitness level. Energy intake was positively related to body fat after controlling for age, fitness level, and body weight. When subjects were separated into low-, moderate-, and high-body-fat groups, the fattest subjects reported eating significantly more dietary fat (P = .05) and less carbohydrate (P = .01), complex carbohydrate (P = .01), and fiber (P = .005) than the leanest subjects. No significant difference in reported energy intake was noted across body fat groups.
Composition of the diet may play a role in obesity beyond energy intake in men over the long-term. Lifestyle changes for men should probably include modifications in diet composition, especially increased consumption of foods high in complex carbohydrate and fiber.
We have studied the effects of TNF-alpha on the mRNAs coding for the peroxisome proliferator activated receptor alpha (PPAR-alpha), and for catalase (Cat), acyl-CoA oxidase (AOX), multifunctional enzyme (PH), and beta-actin in rat liver. Total RNA was isolated from livers of male SD-rats 16 h after administration of a single dose of 25 microg TNF-alpha and mRNAs were analyzed by a novel dot blot RNase protection assay. The mRNAs for PPAR-alpha and for Cat, AOX and PH were significantly reduced by TNF-treatment. In addition, the level of PPAR-alpha protein was also decreased after TNF. In contrast, the mRNA for beta-actin was markedly increased implying that the effect of TNF on PPAR-alpha and the peroxisomal mRNAs is highly selective. This effect may have important implications in perturbation of the lipid metabolism induced by TNF-alpha.
The CYP4A1 isoenzyme induced in rodents by peroxisome proliferators is known to be repressed at a pretranslational level by interferon. Interleukin-1beta (IL-1beta) also reduces CYP4A1-related 12-laurate hydroxylase activity in cultured fetal rat hepatocytes after induction by clofibric acid. In this fetal hepatocyte model, IL-1beta and interleukin-6 (IL-6) were tested for their ability to reduce 12-laurate hydroxylase activity, CYP4A1 apoprotein content, and the CYP4A1 mRNA level. IL-1beta and IL-6 strongly diminished CYP4A1 activity and apoprotein and mRNA levels in a dose- and time-dependent manner. CYP4A1 expression is thus down-regulated at a pretranslational level by these cytokines. As it has been shown that the peroxisome proliferator-activated receptor alpha (PPAR alpha) mediates the induction of the CYP4A1 gene by a peroxisome proliferator, the capacity of IL-1beta or IL-6 to modulate the PPAR alpha mRNA level was tested. It was found that IL-1beta and IL-6 both repress the induction of PPAR alpha expression exerted by the combined action of clofibric acid and dexamethasone. However, even at the highest concentration (10 ng/mL) tested for both cytokines, IL-1beta as well as IL-6 failed to abolish the induction of CYP4A1 by dexamethasone. The mechanism of the protective effect of the synthetic glucocorticoid on CYP4A1 repression by interleukins is discussed.
Tea catechins, (-)-epigallocatechin-3-gallate (EGCg) and (-)-epigallocatechin (EGC), have been reported to suppress oxidation of plasma low density lipoprotein (LDL) in vitro. If dietary catechins can be efficiently incorporated into human blood plasma, anti-atherosclerotic effects in preventing oxidative modification of LDL would be expected. In this study, a newly developed chemiluminescence detection-high pressure liquid chromatography (CL-HPLC) method for measuring plasma catechins was used and the incorporation of EGCg and EGC into human plasma was investigated. Healthy subjects orally ingested 3, 5, or 7 capsules of green tea extract (corresponding to 225, 375, and 525 mg EGCg and 7.5, 12.5, and 17.5 mg EGC, respectively). The plasma EGCg and EGC concentrations before the administration were all below the detection limit (< 2 pmol/ml), but 90 min after, significantly and dose-dependently increased to 657, 4300, and 4410 pmol EGCg/ml, and 35, 144, and 255 pmol EGC/ml, in the subjects who received 3, 5, and 7 capsules, respectively. Both EGCg and EGC levels detected in plasma corresponded to 0.2-2.0% of the ingested amount. Catechin intake had no effect on the basal level of endogenous antioxidants (alpha-tocopherol, beta-carotene, and lycopene) or of lipids in plasma. These results suggested that drinking green tea daily would contribute to maintain plasma catechin levels sufficient to exert antioxidant activity against oxidative modification of lipoproteins in blood circulation systems.
There exists much evidence suggesting a major role for the oxidized low density lipoprotein (LDL) and VLDL particles in the pathogenesis of atherosclerosis. Although obesity is characterized by dyslipidemia, less is known about the oxidation capacity of lipoproteins in obese subjects. We measured the oxidizability in vitro in 21 premenopausal women with a BMI of 36.7+/-5.4 and compared them to 18 age-matched controls (BMI 21.9+/-1.8). The oxidizability of the non-HDL fraction is evaluated by measuring the fluorescence and thiobarbituric acid reactive substances (TBARS; MDA nM/mg non-HDL) at different time intervals of incubation. TBARS formation increased linearly with the increase of lipids both in non-obese and obese subjects. TBARS, measured every 30 min, increased in non-obese controls up to a maximum of 59.6 at 180' in contrast to a maximum of 77.1 at 180' (P < 0.001) in obese, but healthy, normocholesterolemic subjects. At each measurement the TBARS were significantly higher (P < 0.01-0.001) in obese subjects. Also the lag-time (period from zero to the start of the particle oxidation process) was significantly lower (92.5 vs. 123.4; P < 0.001) in obese subjects, when compared to lean controls. BMI correlates significantly with TBARS formation and its log transformed values (maximum P < 0.001). The lag-time was negatively related (n=39 total group, r=- 0.57, P < 0.001) to body weight and BMI. A significant relationship exists between TBARS formation (up to r=0.59) and triglyceride levels and a negative relationship exists with HDL-cholesterol levels. In vitro oxidizability of non-HDL lipoproteins is significantly increased in obese, non-diabetic subjects and related to increased body weight and triglyceride levels. Further studies are necessary to explore the underlying mechanisms for this phenomenon.
These studies were designed to test the hypolipidemic activity of green tea epicatechins (GTE) isolated from jasmine green tea. In Experiment 1, three groups of hamsters were given a semisynthetic diet containing 200 g lard/kg and 1 g cholesterol/kg for 4 wk. The control group received distilled water, and the other two groups received either 15 g/L green tea water extract (GTWE) or 5.0 g/L GTE solution. Both the GTWE and GTE groups had lower concentrations of serum total cholesterol (TC) and triacylglycerols (TG) than the controls (P < 0.05). In Experiment 2, four groups of hamsters received tap water as the drinking fluid, but they were given the same high fat and cholesterol diet supplemented with 0 (control), 1.1, 3.4 or 5.7 g GTE/kg diet. The hypolipidemic effect of jasmine GTE was dose dependent. In Experiment 3, the time-course of changes in serum TC and TG was monitored in hamsters given the high fat diet supplemented with 5.7 g GTE/kg in comparison with that of controls. The hypolipidemic effects of dietary GTE were evident after feeding for 2 wk. Dietary supplementation of GTE did not affect liver fatty acid synthase. However, GTE-supplemented hamsters had higher fecal excretions of total fatty acids, neutral sterols and acidic sterols compared with the control group. In Experiment 4, hamsters were fed nonpurified diet; the control group drank distilled water, and the GTE group drank distilled water containing 5.0 g GTE/L. No differences in activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and intestinal acyl CoA:cholesterol acyltransferase were observed. This study suggests that the hypolipidemic activity of GTE is not due to inhibition of synthesis of cholesterol or fatty acid but is most likely mediated by its influence on absorption of dietary fat and cholesterol.
Current interest in the role of functional foods in weight control has focused on plant ingredients capable of interfering with the sympathoadrenal system.
We investigated whether a green tea extract, by virtue of its high content of caffeine and catechin polyphenols, could increase 24-h energy expenditure (EE) and fat oxidation in humans.
Twenty-four-hour EE, the respiratory quotient (RQ), and the urinary excretion of nitrogen and catecholamines were measured in a respiratory chamber in 10 healthy men. On 3 separate occasions, subjects were randomly assigned among 3 treatments: green tea extract (50 mg caffeine and 90 mg epigallocatechin gallate), caffeine (50 mg), and placebo, which they ingested at breakfast, lunch, and dinner.
Relative to placebo, treatment with the green tea extract resulted in a significant increase in 24-h EE (4%; P < 0.01) and a significant decrease in 24-h RQ (from 0.88 to 0.85; P < 0.001) without any change in urinary nitrogen. Twenty-four-hour urinary norepinephrine excretion was higher during treatment with the green tea extract than with the placebo (40%, P < 0.05). Treatment with caffeine in amounts equivalent to those found in the green tea extract had no effect on EE and RQ nor on urinary nitrogen or catecholamines.
Green tea has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content per se. The green tea extract may play a role in the control of body composition via sympathetic activation of thermogenesis, fat oxidation, or both.
The thermogenic effect of tea is generally attributed to its caffeine content. We report here that a green tea extract stimulates brown adipose tissue thermogenesis to an extent which is much greater than can be attributed to its caffeine content per se, and that its thermogenic properties could reside primarily in an interaction between its high content in catechin-polyphenols and caffeine with sympathetically released noradrenaline (NA). Since catechin-polyphenols are known to be capable of inhibiting catechol-O-methyl-transferase (the enzyme that degrades NA), and caffeine to inhibit trancellular phosphodiesterases (enzymes that break down NA-induced cAMP), it is proposed that the green tea extract, via its catechin-polyphenols and caffeine, is effective in stimulating thermogenesis by relieving inhibition at different control points along the NA-cAMP axis. Such a synergistic interaction between catechin-polyphenols and caffeine to augment and prolong sympathetic stimulation of thermogenesis could be of value in assisting the management of obesity. International Journal of Obesity (2000) 24, 252-258
Peroxisome proliferator-activated receptors (PPAR) are ligand-activated transcription factors which form a subfamily of the nuclear receptor gene family. PPAR activators have effects on both metabolic risk factors and on vascular inflammation related to atherosclerosis. PPAR have profound effects on the metabolism of lipoproteins and fatty acids. PPAR alpha binds hypolipidemic fibrates, whereas PPAR gamma has a high affinity for antidiabetic glitazones. Both PPAR are activated by fatty acids and their derivatives. Activation of PPAR alpha increases the catabolism of fatty acids at several levels. In the liver, it increases uptake of fatty acids and activates their beta-oxidation. The effects that PPAR alpha exerts on triglyceride-rich lipoproteins is due to their stimulation of lipoprotein lipase and repression of apolipoprotein CIII expression, while the effects on high-density lipoproteins depend upon the regulation of apolipoproteins AI and AII. PPAR gamma has profound effects on the differentiation and function of adipose tissue, where it is highly expressed. PPAR are also expressed in atherosclerotic lesions. PPAR are present in vascular endothelial cells, smooth muscle cells, monocytes, and monocyte-derived macrophages. Via negative regulation of nuclear factor-kappa B and activator protein-1 signalling pathways, PPAR alpha inhibits expression of inflammatory genes, such as interleukin-6, cyclooxygenase-2, and endothelin-1. Furthermore, PPAR alpha inhibits expression of monocyte-recruiting proteins such as vascular cell adhesion molecule (VCAM)-1 and induces apoptosis in monocyte-derived macrophages. PPAR gamma activation in macrophages and foam cells inhibits the expression of activated genes such as inducible nitric oxide synthase, matrix metalloproteinase-9 and scavenger receptor A. PPAR gamma may also affect the recruitment of monocytes in atherosclerotic lesions as it is involved in the expression of VCAM-1 and intracellular adhesion molecule-1 in vascular endothelial cells. The involvement of PPAR in atherosclerosis, a disease with a chronic inflammatory character, suggests that they may play a role in other inflammatory-related diseases as well.
According to traditional Chinese belief, oolong tea is effective in the control of body weight. Few controlled studies, however, have been conducted to measure the impact of tea on energy expenditure (EE) of humans. A randomized cross-over design was used to compare 24-h EE of 12 men consuming each of four treatments: 1) water, 2) full-strength tea (daily allotment brewed from 15 g of tea), 3) half-strength tea (brewed from 7.5 g tea) and 4) water containing 270 mg caffeine, equivalent to the concentration in the full-strength tea treatment. Subjects refrained from consuming caffeine or flavonoids for 4 d prior to the study. Tea was brewed each morning; beverages were consumed at room temperature as five 300 mL servings. Subjects received each treatment for 3 d; on the third day, EE was measured by indirect calorimetry in a room calorimeter. For the 3 d, subjects consumed a typical American diet. Energy content of the diet was tailored to each subject's needs as determined from a preliminary measure of 24-h EE by calorimetry. Relative to the water treatment, EE was significantly increased 2.9 and 3.4% for the full-strength tea and caffeinated water treatments, respectively. This increase over water alone represented an additional expenditure of 281 and 331 kJ/d for subjects treated with full-strength tea and caffeinated water, respectively. In addition, fat oxidation was significantly higher (12%) when subjects consumed the full-strength tea rather than water.
The green tea extract AR25 is an 80% ethanolic dry extract standardized at 25% catechins expressed as epigallocatechin gallate (EGCG). In vitro, green tea extract AR25 exerts a direct inhibition of gastric and pancreatic lipases and a stimulation of thermogenesis. In an open study, the effects of extract AR25 were evaluated in moderately obese patients. After 3 months, body weight was decreased by 4.6% and waist circumference by 4.48%. These results suggest the green tea extract AR25 to be a natural product for the treatment of obesity, which exerts its activity by several ways: inhibition of lipases and stimulation of thermogenesis.
Antioxidativeeffectsofblacktea theaflavins and thearubigin on lipid peroxidation of rat liver homoge-nates induced by tert-butyl hydroperoxide
- Yoshinok
- Haray
- Sanom
YoshinoK,HaraY,SanoM,TomitaI.Antioxidativeeffectsofblacktea theaflavins and thearubigin on lipid peroxidation of rat liver homoge-nates induced by tert-butyl hydroperoxide. Biol Pharm Bull 1994;17: 146–9
Tea in chemoprevention of cancer: epidemiologic and experimental studies
- Katiyar
Katiyar SK, Mukhtar H. Tea in chemoprevention of cancer: epidemio-logic and experimental studies. Int J Oncol 1996;8:221–38
Regionalobesityandriskofcardiovasculardisease:theFramingham Study
- Wb Kannel
- La Cupples
- R Ramaswami
- J Stokes
- Be Kreger
- Higgins
Kannel WB, Cupples LA, Ramaswami R, Stokes J, Kreger BE, Higgins M.Regionalobesityandriskofcardiovasculardisease:theFramingham Study. J Clin Epidemiol 1991;44:183–90
- Nanjo
Effect of green tea catechins on plasma cholesterol level in cholesterol-fed rats
- Muramatsu
Effect of epicatechin on liver lipids of rats fed with choline deficient diet
- Chaudhari
- F Nanjo
- Y Hara
- Y Kikuchi
- CT Ho
Ion selective electrode
- Kuwa
Outline of research activitites of the National Institute of Health and Nutrition Outline of research activities in 1999
- H Sawa