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Abstract

Background: Green tea catechins have been hypothesized to increase energy expenditure and fat oxidation by inhibiting catechol-O-methyltransferase (COMT) and thus promoting more sustained adrenergic stimulation. Metabolomics may help to clarify the mechanisms underlying their putative physiological effects. Objective: The study investigated the effects of 7-day ingestion of green tea extract (GTE) on the plasma metabolite profile at rest and during exercise. Methods: In a placebo-controlled, double-blind, randomized, parallel study, 27 healthy physically active males consumed either GTE (n=13, 1200 mg catechins, 240 mg caffeine/day) or placebo (n=14, PLA) drinks for 7 days. After consuming a final drink (day 8), they rested for 2 h and then completed 60 min of moderate-intensity cycling exercise (56% ± 4% VO(2)max). Blood samples were collected before and during exercise. Plasma was analyzed using untargeted four-phase metabolite profiling and targeted profiling of catecholamines. Results: Using the metabolomic approach, we observed that GTE did not enhance adrenergic stimulation (adrenaline and noradrenaline) during rest or exercise. At rest, GTE led to changes in metabolite concentrations related to fat metabolism (3-β-hydroxybutyrate), lipolysis (glycerol) and tricarboxylic acid cycle (TCA) cycle intermediates (citrate) when compared to PLA. GTE during exercise caused reductions in 3-β-hydroxybutyrate concentrations as well as increases in pyruvate, lactate and alanine concentrations when compared to PLA. Conclusions: GTE supplementation resulted in marked metabolic differences during rest and exercise. Yet these metabolic differences were not related to the adrenergic system, which questions the in vivo relevance of the COMT inhibition mechanism of action for GTE.

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... Moreover, animal studies have demonstrated that tea catechins may induce acute increases in FO rates [29][30][31]. In this section, we have summarized relevant literature on the effect of GT intake [35] **** * ** 7 Eichenberger et al. [37] *** ** * 6 Eichenberger et al. [36] *** * * 5 Sugita et al. [38] ** * ** 5 Randell et al. [39] **** ** * 7 Jacobs et al. [43] *** * * 5 Martin et al. [44] *** * ** 6 Randell et al. [42] *** -** 5 Gahreman et al. [33] **** ** ** 8 Roberts et al. [34] **** -* 5 Blicher et al. [40] *** * * 5 Ota et al. [18] **** * * 6 Ichinose et al. [19] **** ** * 7 Rostamian and Bijeh [17] *** * ** 6 Roberts et al. [20] **** * ** 7 Cardoso et al. [22] **** * ** 7 Maki et al. [53] ** * * 4 Bagheri et al. [55] **** ** * 7 Bagheri et al. [54] *** -** 5 Hanachi et al. [21] **** ** * 7 Amozadeh et al. [57] **** * * 6 Bonab [58] **** * * 6 Ghadami et al. [59] **** ** * 7 Moradi et al. [60] ** * ** 5 Abedi et al. [61] **** -** 6 Alikhani et al. [56] **** ** * 7 ...
... In this regard, Randell et al. [42] showed in another study that dGTE supplementation (1136 mg/day total catechins, 624 mg/day EGCG, and ~ 11 mg/day caffeine) had no effects on markers of lipolysis (i.e., plasma concentrations of FA and glycerol) and substrate metabolism during a 30 min exercise bout (cycling at 55% VO 2max ) on day 1 and after 7 or 28 days. Similarly, in a study with similar supplementation and exercise protocol, Jacobs et al. [43] showed no change in lipolysis markers in healthy trained men. However, although no metabolic effect of short-term dGTE consumption (2 days, 1000 mg/day containing 450 mg/day EGCG, and ~ 9 mg/day caffeine) during moderate-intensity exercise was confirmed in a study conducted by Martin et al. [44] plasma glycerol was increased, suggesting a potential increase in lipolysis rate. ...
... Overall, the findings regarding the metabolic effects of GT during exercise are contradictory. While some studies have shown that acute (24 h) or short-term (4 weeks) consumption of GT may increase FO during or after moderate-intensity exercise [32][33][34], other studies did not confirm these results [36][37][38][39][40][42][43][44]. ...
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Background Green tea (GT) consumption may influence fat oxidation (FO), body composition and blood lipid profile in human subjects. Therefore, this study aimed to review the current literature regarding the interactive effect of aerobic and resistance training with GT ingestion on these parameters. Methods Electronic searches were performed in Google Scholar, PubMed, Elsevier, Science Direct, and national databases. Only studies on human subjects that included GT intervention and aerobic or resistance exercise from any date to May 30, 2021 were reviewed. Results Twenty-seven papers (n = 831 participants) were included. From these, 12 studies addressed the acute or short-term effect of GT consumption on substrate oxidation during exercise, 2 studies assessed the long-term effect of GT consumption and aerobic exercise on substrate oxidation during exercise, 9 studies examined the short-term or long-term effects of GT intake and aerobic exercise on substrate oxidation or cardiometabolic risk factors, and 4 studies investigated the long-term effects of GT consumption and resistance training on substrate oxidation or cardiometabolic risk factors. Conclusions Short-term consumption of GT may have positive metabolic effects during moderate-intensity exercise in inactive people or those who exercise recreationally. Likewise, a combination of moderate-intensity aerobic training and GT consumption for a minimum period of 8 to 10 weeks can increase FO during exercise in healthy individuals. Regular resistance training combined with GT consumption may have potential benefits in enhancing body composition, lowering triglyceride, and increasing high-density lipoprotein in sedentary obese/overweight people.
... Del total de los 13 artículos originales seleccionados, el 69% se tratan de estudios con un entrenamiento diseñado 6,7,15-21 . El 92% de los estudios incluidos han incluido un test de ejercicio físico para valorar parámetros [6][7][8][9][16][17][18][19][21][22][23] . ...
... El 100% de los ensayos clínicos, incluyeron participantes adultos suplementados con GT o sucedáneos. La mayoría de rango de edades (77%) oscila entre 20-40 años 6,7,[15][16][17][18][19][21][22][23] . Basándonos en la clasificación de la duración de los artículos 24 , encontramos que el 69% de los ensayos clínicos son de larga duración [6][7][8][15][16][17][18]21,22 . ...
... La mayoría de rango de edades (77%) oscila entre 20-40 años 6,7,[15][16][17][18][19][21][22][23] . Basándonos en la clasificación de la duración de los artículos 24 , encontramos que el 69% de los ensayos clínicos son de larga duración [6][7][8][15][16][17][18]21,22 . El tamaño de la muestra osciló entre 9 y 36 individuos. ...
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Purposes: assessing the magnitude of the effects of green tea in subjects that do exercise. Methodology: a search was been carried out with key words "green tea" AND "exercise" in four documentary databases: Pubmed, EBSCOHOST, OvidSP and Proquest. Inclusion criteria: adult age of the sample (18-65 years, based on WHO), and the consumption of a quantified amount of green tea or substitutes, along with doing physical exercise measurable in intensity, in clinical tests published between January 2010 and December 2014, whose source were indexed scientific journals. Results: 260 articles were analyzed, of which 13 items were selected. 69% are studies with a designed workout, and 92% have included an exercise test to assess parameters. 77% fluctuate between 20-40 years and sample size between 9 and 36 subjects. 69% are long length. GTE has been the most used substitute (38%). 92% of studies have obtained some improvement and 92% of them, were significantly statistic. Interpretation of results: little homogeneity has been found in results in the analysis of results expression. Sample size is limited. There is a wide range of GTE substitutes and diversity of doses and exercise done. It cannot be possible to establish a dose, dosage and physical activity recommended. Conclusions: green tea gives us a wide variety of benefits in combination with physical exercise. There is a little evidence about quality. It cannot be possible to establish specific recommendations for obtaining benefits.
... On the other hand, some human studies did not support stimulating effect of GTE supplementation on fat oxidation during exercise (Eichenberger et al., 2009;Dean et al., 2009;Hodgson et al., 2013). In double-blind, crossover study by Eichenberger et al. (2009), healthy endurance-trained men ingested, for 21 days, GTE (159 mg catechins/day, of which 68 mg/day was EGCG, and only 28 mg caffeine/day) or placebo (corn starch). ...
... Therefore, positive effect of green tea on thermogenesis and fat oxidation may be attributed to an interaction between green tea catechins and caffeine on sympathetic activity rather than individual catechin components (Dean et al., 2009). In more recent study (Hodgson et al., 2013), in healthy physically active men, the metabolic responses following 7-day GTE supplementation (1200 mg catechins + 240 mg caffeine/day consumed in two doses: before breakfast and dinner) at rest and during moderate-intensity exercise (60-min cycling at 56%VO 2max ) was examined using gas and liquid chromatography-mass spectrometry. As indicated by metabolic profiling, GTE enhanced lipolysis and fat oxidation when compared to placebo, but only under resting conditions, whereas no effect of GTE was seen during exercise. ...
... Because the metabolic effects observed during exercise were largely attributed to acute ingestion of the last dose of green tea (for 2h before exercise), the authors concluded that a single dose of GTE used may not be potent enough to stimulate further metabolism above that already up-regulated by exercise. Moreover, supplementation period in these two studies (Dean et al., 2009;Hodgson et al., 2013) seems to be too short (6-7 day) to exert adaptive stimulating effect of GTE on exercise fat metabolism. ...
... On the other hand, some human studies did not support stimulating effect of GTE supplementation on fat oxidation during exercise (Eichenberger et al., 2009;Dean et al., 2009;Hodgson et al., 2013). In double-blind, crossover study by Eichenberger et al. (2009), healthy endurance-trained men ingested, for 21 days, GTE (159 mg catechins/day, of which 68 mg/day was EGCG, and only 28 mg caffeine/day) or placebo (corn starch). ...
... Therefore, positive effect of green tea on thermogenesis and fat oxidation may be attributed to an interaction between green tea catechins and caffeine on sympathetic activity rather than individual catechin components (Dean et al., 2009). In more recent study (Hodgson et al., 2013), in healthy physically active men, the metabolic responses following 7-day GTE supplementation (1200 mg catechins + 240 mg caffeine/day consumed in two doses: before breakfast and dinner) at rest and during moderate-intensity exercise (60-min cycling at 56%VO 2max ) was examined using gas and liquid chromatography-mass spectrometry. As indicated by metabolic profiling, GTE enhanced lipolysis and fat oxidation when compared to placebo, but only under resting conditions, whereas no effect of GTE was seen during exercise. ...
... Because the metabolic effects observed during exercise were largely attributed to acute ingestion of the last dose of green tea (for 2h before exercise), the authors concluded that a single dose of GTE used may not be potent enough to stimulate further metabolism above that already up-regulated by exercise. Moreover, supplementation period in these two studies (Dean et al., 2009;Hodgson et al., 2013) seems to be too short (6-7 day) to exert adaptive stimulating effect of GTE on exercise fat metabolism. ...
... Acute and chronic physical activity causes extensive adaptations in organs and systems, leading to health benefits [1]. Improvements in technology have allowed investigators to quantify these adaptations using a biological systems approach, overlaying gene information with transcriptomics, proteomics, and metabolomics [1][2][3][4][5][6][7][8][9][10]. Combined data from multi-omics approaches will improve scientific understanding regarding the complex modulating effect that physical activity has on the phenotype at the individual level and related molecular mechanisms. ...
... Two studies investigated metabolite responses to moderate-intensity, long-duration cycling and cross-country skiing [10,11]. Small to moderate post-exercise changes were reported for metabolites related to glycolytic and lipid pathways including free fatty acids, branched chain amino acids, acylcarnitines, mono-and diacylglycerols, and TCA intermediates. ...
... Summaries of study characteristics and findings from nine[6,10,11,15,23,[25][26][27][28] studies using other types of exercise designs.Double-blind, randomized, parallel design; 7-day supplementation with caffeinated green tea or placebo ingestion 2-h before 60-min cycle exercise at 50%VO 2max 238 metabolites chemically detected changed with exercise; ↑ ratio > 2: lactate, pyruvate, succinate, noradrenaline and glycerol; ↓ 2-hydroxybutyrate, trans-4-hydroxyproline, mannose, certain triacylglycerides (TAGs) and nicotinamide. changed with MOD only); ↑ in carbohydrate oxidation and ↓ in fat oxidation in HIIT exercise compared to MOD; Glucose and lactate higher at 0-h in HIIT compared to MOD. ...
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This systematic review provides a qualitative appraisal of 24 high-quality metabolomics-based studies published over the past decade exploring exercise-induced alterations of the human metabolome. Of these papers, 63% focused on acute metabolite changes following intense and prolonged exercise. The best studies utilized liquid chromatography mass spectrometry (LC-MS/MS) analytical platforms with large chemical standard libraries and strong, multivariate bioinformatics support. These studies reported large-fold changes in diverse lipid-related metabolites, with more than 100 increasing two-fold or greater within a few hours post-exercise. Metabolite shifts, even after strenuous exercise, typically return to near pre-exercise levels after one day of recovery. Few studies investigated metabolite changes following acute exercise bouts of shorter durations (< 60 min) and workload volumes. Plasma metabolite shifts in these types of studies are modest in comparison. More cross-sectional and exercise training studies are needed to improve scientific understanding of the human system’s response to varying, chronic exercise workloads. The findings derived from this review provide direction for future investigations focused on the body’s metabolome response to exercise.
... Catechins available in green tea with an inhibitory influence on phospholipase A 2 causes a decrease in lipid absorption, and lipogenes is inhibition by controlling synthetic fatty acid gene transcription and acetyl CoA carboxylase, and an increase of fat oxidation, capillary network function, and mitochondrial density and finally leads to an increase in VO 2max and a decrease in fat weight. [13,29] On the other hand, it seems that existing catechins in green tea bring about an inhibition of LDL oxidation by copper sulfate, and cholesterol synthesis. The other possible mechanism for LDL decrease relates to the interference of micelles of cholesterol in the digestive system through the formation of insoluble cholesterol, results in cholesterol excretion through feces then the inhibition of cholesterol absorption occurs. ...
... The other possible mechanism for LDL decrease relates to the interference of micelles of cholesterol in the digestive system through the formation of insoluble cholesterol, results in cholesterol excretion through feces then the inhibition of cholesterol absorption occurs. On the other hand, the inhibition of LDL oxidation and fibrinogen binding, through the epigallo catechin existing in green tea, leads to decrease its functionality and increase anxiolytic activity in serum, eventually attenuate fibrinogen and improve HDL levels, [29] of course it seems that the combination of supplementary and physical activity, accelerates the result. [30] We suggest further studies with more number of samples and more assessment to conclude whether the positive effects of training with green tea will remain or not. ...
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Background: Considered the increasing rate of cardiovascular diseases (CVDs) and a positive relationship between prevalence of CVDs and obesity, the goal of the present study was to investigate the effects of green tea supplement and high-intensity interval training (HIIT) on lipid panel, fibrinogen, and maximal oxygen consumption (VO2max) in overweight women. Materials and methods: In this randomized placebo-controlled clinical trial, 30 overweight women (age range, 20-30 years), were chosen purposefully and randomly divided into three equal groups (green tea, HIIT + green tea, and HIIT + placebo), and they trained HIIT workouts for 10 weeks (40-m maximal shuttle run) and used 500 mg/daily green tea or placebo tablets. Serum levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride (TG), and plasma level of fibrinogen were assessed before and after the intervention in fasting state. To test the hypothesis of the research, Paired t-test, Wilcoxon signed-rank test, analysis of covariance, and Tukey's post hoc tests were used at the significance level of P ≤ 0.05. Results: After 10 weeks, TG, LDL, weight, fibrinogen, and body fat percentage decreased in all groups (P ≤ 0.05). Further, HDL (P = 0.012) and VO2max (P = 0.007) significantly increased in HIIT + green tea and HIIT + placebo groups; while in the green tea group, HDL (P = 0.06) and VO2max (P = 0.06) showed no significant difference for within group differences. Average between-group variations of all indicators were statistically significant, and they were more meaningfully pronounced in HIIT + green tea group than the other two groups (P ≤ 0.05). Conclusion: Based on the findings, the combination of HIIT and green tea consumption significantly leads to a reduction in weight, body fat percentage, fibrinogen, TG, and LDL while improves VO2max and HDL levels rather than green tea consumption or performing training alone, in overweight women. However, it seems that exercise training has a vital role in the improvement of mentioned variables according to percentage changes.
... Several studies have investigated the effects of GTC on metabolic and physiological function during exer- cise. It has been shown that GTC increased fat oxidation during exercise, improved maximal V ˙ O 2 , lowered steady-state exer- cise HR, and increased markers of lipolysis (32,36,39,46); however, these findings remain equivocal, as many others have been unable to replicate the findings (11,18,19,31,32,36,38). As previously stated, GTC are purported to increase adrenergic drive through increased -receptor stimulation (12,29). ...
... As previously stated, GTC are purported to increase adrenergic drive through increased -receptor stimulation (12,29). And again, data from investigations examining these effects of GTE on catecholamines in humans have failed to show an effect (18,32). Although several other mechanisms have been observed in rodent models (20), none of these mechanisms has been followed up in humans. ...
Article
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We reported that supplementation with green tea extract (GTE) lowered the glycemic response to an oral glucose load following exercise but via an unknown mechanism. Here we examined the effect of supplementation with GTE on plasma glucose kinetics upon ingestion of a glucose beverage during exercise recovery. Eleven healthy, sedentary men (21±2 y; BMI=23±4 kg•m(-2), VO2peak=38±7 ml•kg(-1)•min(-1); mean±SD) ingested GTE (350 mg) or placebo (PLA) thrice daily for 7-d in a double-blind, crossover design. In the fasted state, a primed constant infusion of [U-(13)C6] glucose was started, and 1-h later, subjects performed a graded-exercise test (25 Watts/3 min) on a cycle ergometer. Immediately post-exercise, subjects ingested a 75g glucose beverage containing 2g of [6,6-(2)H2] glucose, and blood samples were collected every 10-min for 3-h of recovery. The rate of carbohydrate oxidation was lower during exercise after GTE vs. PLA (1.26±0.34 vs. 1.48±0.51 g•min(-1), P=0.04). Glucose area under the curve (AUC) was not different between treatments after drink ingestion (GTE=1067±133 vs. PLA=1052±91 mM•180 min, P=0.91). Insulin AUC was lower after GTE vs. PLA (5673±2153 vs. 7039±2588 µIU•180 min, P=0.05), despite similar rates of glucose appearance (GTE=0.42±0.16 vs. PLA=0.43±0.13, g•min(-1), P=0.74) and disappearance (GTE=0.43±0.14 vs. PLA=0.44±0.14, g•min(-1), P=0.57). We conclude that short-term GTE supplementation did not affect glucose kinetics following ingestion of an oral glucose load post-exercise; however, GTE was associated with attenuated insulinemia. These findings suggest GTE lowers the insulin required for a given glucose load during post-exercise recovery, which warrants further mechanistic studies in humans.
... Enhanced fat oxidation was thought to be due to inhibition of catechol-O-methyltransferase (COMT), an enzyme degrading catecholamines. However, four-phase metabolite profiling with both gas and liquid chromatography-mass spectrometry showed large inter-individual differences among healthy active males in response to GTE drink and exercise[2]. The GTE drink contained 207.5 mg of EGCG and 120.4 mg of caffeine. ...
... Subsequently, a study by Lorenz et al.[3]provided evidence that COMT activity was actually increased by 24% in healthy males and females with an acute dose of 750 mg EGCG. Both studies by Hodgson et al.[2]and Lorenz et al.[3]will initiate future studies to address the mechanism for enhanced exercise-induced fat oxidation by green tea, with genetic predisposition to be important whether subjects are responsive to effects of green tea intake[4]. Overall, our understanding of the in vivo effects of green tea on exercise-induced fat oxidation seems to be in its infancy. ...
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We are glad to introduce the new Journal Club. This edition is focused on several relevant studies published in recent years in the field of Exercise and Nutrition for Health, chosen by our Editorial Board members. We hope to stimulate your curiosity in this field and to share with you the importance of aspects of exercise and nutrition seen also from the scientific point of view.
... For example, Gahreman et al. (2015) [35] combined green tea with intermittent exercise and showed an increased FAO, plasma glycerol, and plasma catecholamines at rest and post exercise compared with placebo in healthy active female participants of similar characteristics to the present study. Another study by Hodgson et al. (2013) [36] found that a drink containing 1.2 g of green tea affected the metabolic profile (3-β-hydroxybutyrate, pyruvate, lactate and alanine concentrations) at rest and during 60 min of exercise at 56% . VO 2peak compared with placebo. ...
... For example, Gahreman et al. (2015) [35] combined green tea with intermittent exercise and showed an increased FAO, plasma glycerol, and plasma catecholamines at rest and post exercise compared with placebo in healthy active female participants of similar characteristics to the present study. Another study by Hodgson et al. (2013) [36] found that a drink containing 1.2 g of green tea affected the metabolic profile (3-β-hydroxybutyrate, pyruvate, lactate and alanine concentrations) at rest and during 60 min of exercise at 56% . VO 2peak compared with placebo. ...
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Yerba Maté (YM), has become a popular herb ingested for enhancing metabolic health and weight-loss outcomes. No studies have tested the combined metabolic, satiety, and psychomotor effects of YM during exercise. We tested whether YM ingestion affects fatty acid oxidation (FAO), profile of mood state score (POMS), and subjective appetite scale (VAS), during prolonged moderate exercise. Twelve healthy active females were randomized to ingest either 2 g of YM or placebo (PLC) in a repeated-measures design. Participants rested for 120 min before performing a 30-min cycling exercise corresponding to individuals’ crossover point intensity (COP). FAO, determined using indirect calorimetry, was significantly higher during the 30-min exercise in YM vs. PLC (0.21 ± 0.07 vs. 0.17 ± 0.06 g/min, p < 0.05). VAS scores for hunger, prospective eating, and desire to eat were all reduced (p < 0.05). Whereas, POMS measures of focus, energy, and concentration were all increased (p < 0.05). There was no significant time-effect for any of the measured variables, nor was there any interaction effects between YM treatment and time. Combining YM intake with prolonged exercise at targeted ”fat-loss”’ intensities augments FAO and improves measures of satiety and mood state. Such positive combined metabolic, satiety, and psychomotor effects may provide an important role for designing future fat and weight-loss lifestyle interventions.
... Up-regulated p-p85 and p-Akt levels. ( Hodgson et al., 2013) Inflammation (randomized, split-face trial) 35 patients with Acne (17 men and 18 women, mean age: 22.1) 1% or 5% topical solution for twice a day Significantly reduced inflammation by inhibiting NF-kB and AP-1 pathways. ...
... These results suggest that dietary supplementation with EGCG did not alter adiposity content and did not improve weight loss-induced changes in cardiometabolic risk factors in women following energy-restricted diet intervention (Mielgo-Ayuso et al., 2014). In contrast, when 27 healthy male subjects were given 1200 mg EGCG accompanied by 240 mg caffeine per day for 7 days, the citric acid cycle activity, lipolysis, and fat oxidation were increased (Hodgson et al., 2013) (Table 3). ...
Article
Ethnopharmacological relevance: The compound epigallocatechin-3-gallate (EGCG), the major polyphenolic compound present in green tea [Camellia sinensis L. (Theaceae], has shown numerous cardiovascular health promoting activity through modulating various pathways. However, molecular understanding of the cardiovascular protective role of EGCG has not been reported. Aim of the review: This review aims to compile the preclinical and clinical studies that had been done on EGCG to investigate its protective effect on cardiovascular and metabolic diseases in order to provide a systematic guidance for future research. Materials and methods: Research papers related to EGCG were obtained from the major scientific databases, for example, Science direct, PubMed, NCBI, Springer and Google scholar, from 1995 to 2017. Results: EGCG was found to exhibit a wide range of therapeutic properties including anti-atherosclerosis, anti-cardiac hypertrophy, anti-myocardial infarction, anti-diabetes, anti-inflammatory and antioxidant. These therapeutic effects are mainly associated with the inhibition of LDL cholesterol (anti-atherosclerosis), inhibition of NF-κB (anti-cardiac hypertrophy), inhibition of MPO activity (anti-myocardial infarction), reduction in plasma glucose and glycated hemoglobin level (anti-diabetes), reduction of inflammatory markers (anti-inflammatory) and the inhibition of ROS generation (antioxidant). Conclusion: EGCG shows different biological activities and in this review, a compilation of how this bioactive molecule plays its role in treating cardiovascular and metabolic diseases was discussed.
... The increase in post-exercise fat oxidation being driven by enhanced norepinephrine and epinephrine release during ISE causing an increased accumulation of circulatory sulfo-conjugated catecholamines [59]. In contrast to the short half-life of catecholamines (1-3 min) the half-life of sulfo-conjugated catecholamines has been estimated to be 3-4 h [60]. It is thought that green tea catechins increase fat oxidation through inhibition of catechol-O-methyltransferase, the enzyme that degrades norepinephrine, thereby prolonging adrenergic drive [15][16][17]. ...
... That epinephrine levels were also elevated after GTE consumption during exercise also suggests that GTE may increase adrenergic drive. However, no relationship was found between adrenergic drive and blood catecholamine level during a 60-min bout of acute aerobic exercise performed at 56% of maximal oxygen uptake after 7 days of GTE ingestion [60]. In a recent review Hodgson et al. [61] have pointed out that the inhibition of catechol-O-methyltransferase hypothesis has little in vivo support and they suggest that changes in the expression of fat metabolism genes could be brought about with chronic exercise training. ...
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Fat oxidation has been shown to increase after short term green tea extract (GTE) ingestion and after one bout of intermittent sprinting exercise (ISE). Whether combining the two will result in greater fat oxidation after ISE is undetermined. The aim of the current study was to investigate the combined effect of short term GTE and a single session of ISE upon post-exercise fat oxidation. Fourteen women consumed three GTE or placebo capsules the day before and one capsule 90 min before a 20-min ISE cycling protocol followed by 1 h of resting recovery. Fat oxidation was calculated using indirect calorimetry. There was a significant increase in fat oxidation post-exercise compared to at rest in the placebo condition (p < 0.01). After GTE ingestion, however, at rest and post-exercise, fat oxidation was significantly greater (p < 0.05) than that after placebo. Plasma glycerol levels at rest and 15 min during post-exercise were significantly higher (p < 0.05) after GTE consumption compared to placebo. Compared to placebo, plasma catecholamines increased significantly after GTE consumption and 20 min after ISE (p < 0.05). Acute GTE ingestion significantly increased fat oxidation under resting and post-exercise conditions when compared to placebo.
... 40,83À91 Metabolomics-based approaches are particularly valuable in studies combining exercise and nutrition interventions because shifts in hundreds of metabolites from diverse pathways can be measured simultaneously. 2,40,84,86,90 A systematic review of 24 high-quality papers that were published during the past decade revealed that the primary focus of metabolomics-based exercise studies has been on acute metabolite perturbations due to long-duration, high-intensity aerobic exercise. 83 Little information is available regarding metabolite changes coupled with acute moderate bouts of exercise or those associated with long-term exercise training or athletic endeavor. ...
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Several decades of research in the area of exercise immunology have shown that the immune system is highly responsive to acute and chronic exercise training. Moderate exercise bouts enhance immunosurveillance and when repeated over time mediate multiple health benefits. Most of the studies prior to 2010 relied on a few targeted outcomes related to immune function. During the past decade, technologic advances have created opportunities for a multi-omics and systems biology approach to exercise immunology. This article provides an overview of metabolomics, lipidomics, and proteomics as they pertain to exercise immunology, with a focus on immunometabolism. This review also summarizes how the composition and diversity of the gut microbiota can be influenced by exercise, with applications to human health and immunity. Exercise-induced improvements in immune function may play a critical role in countering immunosenescence and the development of chronic diseases, and emerging omics technologies will more clearly define the underlying mechanisms. This review summarizes what is currently known regarding a multi-omics approach to exercise immunology and provides future directions for investigators.
... For meta-analysis, in addition to BMI, WC and TBFM, the parameters EE, RQ and FOX rate were also included in this systematic review and meta-analysis. They were included because they are important diagnostic indicators of fat metabolism, which is considered a major risk factor for overweight and obesity [19,21,[56][57][58]. ...
... In this study plasma glucose and insulin concentrations were concurrently lower in the GTE group, indicating a significant metabolic shift toward lipid oxidation (Venables et al., 2008). More recently, Hodgson et al. (2013) and Randell et al. (2013) demonstrated that 7 days GTE supplementation altered global metabolite profiles and increased lipolysis . ...
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Endurance exercise, when performed regularly as part of a training program, leads to increases in whole-body and skeletal muscle-specific oxidative capacity. At the cellular level, this adaptive response is manifested by an increased number of oxidative fibers (Type I and IIA myosin heavy chain), an increase in capillarity and an increase in mitochondrial biogenesis. The increase in mitochondrial biogenesis (increased volume and functional capacity) is fundamentally important as it leads to greater rates of oxidative phosphorylation and an improved capacity to utilize fatty acids during sub-maximal exercise. Given the importance of mitochondrial biogenesis for skeletal muscle performance, considerable attention has been given to understanding the molecular cues stimulated by endurance exercise that culminate in this adaptive response. In turn, this research has led to the identification of pharmaceutical compounds and small nutritional bioactive ingredients that appear able to amplify exercise-responsive signaling pathways in skeletal muscle. The aim of this review is to discuss these purported exercise mimetics and bioactive ingredients in the context of mitochondrial biogenesis in skeletal muscle. We will examine proposed modes of action, discuss evidence of application in skeletal muscle in vivo and finally comment on the feasibility of such approaches to support endurance-training applications in humans.
... The impact of caffeine on fat metabolism is Obesity Breath Acetone and Fat Loss Anderson expected to be small (<20%) and diminish with habitual ingestion (58). Green tea contains large amounts of catechin polyphenols including epigallocatechin-3-gallate which appears to promote lipolysis and increase fat oxidation (58,60,61). Green tea consumption (>100 mg) can increase fat oxidation both acutely and chronically but its effects can be modulated by caffeine intake (58). ...
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Objective: Endogenous acetone production is a by-product of the fat metabolism process. Because of its small size, acetone appears in exhaled breath. Historically, endogenous acetone has been measured in exhaled breath to monitor ketosis in healthy and diabetic subjects. Recently, breath acetone concentration (BrAce) has been shown to correlate with the rate of fat loss in healthy individuals. In this review, the measurement of breath acetone in healthy subjects is evaluated for its utility in predicting fat loss and its sensitivity to changes in physiologic parameters. Results: BrAce can range from 1 ppm in healthy non-dieting subjects to 1,250 ppm in diabetic ketoacidosis. A strong correlation exists between increased BrAce and the rate of fat loss. Multiple metabolic and respiratory factors affect the measurement of BrAce. BrAce is most affected by changes in the following factors (in descending order): dietary macronutrient composition, caloric restriction, exercise, pulmonary factors, and other assorted factors that increase fat metabolism or inhibit acetone metabolism. Pulmonary factors affecting acetone exchange in the lung should be controlled to optimize the breath sample for measurement. Conclusions: When biologic factors are controlled, BrAce measurement provides a non-invasive tool for monitoring the rate of fat loss in healthy subjects.
... These include, but are not limited to supplementary glucose, various amino acids [6][7][8] (i.e., L-arginine [9], beta-alanine [10,11], citrulline (in the form of citrulline-malate [12,13] or citrulline alone [12,14,15], glutamine [3,16], taurine [17] among other amino acids [18] and/ or a combination of branched-chain amino acids, particularly including L-Leucine [19]. Additional ergogenic and anaplerotic agents have been investigated, including [20][21][22], pyruvate [23][24][25], citrate [26][27][28], or malate [29] alone, creatine [22,30,31] (often in the form of pyruvate-creatine or creatine citrate [32,33], carnitine [34,35], various vitamins [36,37], co-factors [38], and antioxidants [39,40], among many others, particularly plant derived extracts or natural products (for example green tea [41], Cordyceps sinensis and yohimbine [42]) or complex derivatives thereof concocted into fortified beverages with supplementary carbohydrates [28,43] or protein isolates [44]. Additional investigations have explored the augmentation of athletic performance by specifically boosting nitric oxide levels via supplementation with L-arginine [20,45], or indirectly by using an arginine precursor such as citrulline [17] which has been shown to extend time to exhaustion [46]. ...
... Regular consumption of tea, in particular green tea, is associated with beneficial health outcomes and has also been addressed with metabolomics techniques. For example, decaffeinated green tea consumption has been reported to cause increase in 3-hydroxybutyrate as determined by NMR metabolite profiling [48] whereas several phenolic compounds such as hippuric acid, 4-hydroxyhippuric acid, and 1,3dihydroxyphenyl-2-O-sulfate have been detected in urine after consumption of black tea [60]. ...
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The utilization of metabolomics technologies as part of nutritional investigations has rapidly increased during the last few years. The application of both nuclear magnetic resonance (NMR) and mass spectrometry (MS) based technologies is providing wide information on both the diet-derived compounds and their metabolites related to specific foods or diets, as well as aiding the in-depth exploration of the endogenous metabolic phenomena related to different diets. The analytical accuracy nowadays enables examination of metabolite composition of both urine and plasma to very high molecular detail even at low concentrations, and will be focal in gaining wider metabolic understanding of the relationship between eating habits and maintenance of good health.
... Recently, GTE at the dose of 550 mg/kg BW had shown anti-inflammatory effect against uveitis induced by LPS in rats (Qin et al., 2014). In addition, healthy male subjects who received 1200 mg of GTE combined with 240 mg of caffeine beverage for 7 days were able to improve metabolic parameters, including reduced plasma 3-b-hydroxybutyrate and increased pyruvate, lactate and alanine concentrations during moderate-intensity exercise (Hodgson et al., 2013). Moreover, endurance training supplemented with 572.8 mg of GTE in healthy male volunteers for 10 weeks improved a whole-body fat utilization during exercise (Ichinose et al., 2011). ...
Article
1. Green tea extract (GTE) and EGCG have previously shown to increase the uptake of MPP⁺ into Caco-2 cells. However, whether GTE and its derivatives interact with renal basolateral organic cation transporter 2 (Oct2) which plays a crucial role for cationic clearance remains unknown. Thus, this study assessed the potential of drug-green tea (GT) catechins and its derivatives interactions with rat Oct2 using renal cortical slices and S2 stably expressing rat Oct2 (S2rOct2). 2. Both GTE and ECG inhibited MPP⁺ uptake in renal slices in a concentration-dependent manner (IC50 = 2.71 ± 0.360 mg/ml and 0.87 ± 0.151 mM), and this inhibitory effect was reversible. Inhibition of [³H]MPP⁺ transport in S2rOct2 by either GTE or ECG (IC50 = 1.90 ± 0.087 mg/ml and 1.67 ± 0.088 mM) was also observed. 3. The weak and reversible interactions of GTE and ECG with rOct2 indicate that consumption of GT beverages could not interfere with cationic drugs secreted via renal OCT2 in humans. However, the rise of therapeutic use of GTE and ECG might have to take into account the significant possibility of adverse drug–green tea catechins interactions which could alter renal organic cation drug clearance.
... A recent metabolomic study with healthy male subjects demonstrated that green tea extract supplementation (1200 mg catechins and 240 mg caffeine daily) for 7 days increased lipolysis, fat oxidation and citric acid cycle activity under resting conditions without enhancing adrenergic stimulation [40]. The role of caffeine in these studies was inconsistent among the different studies. ...
Article
Tea, a popular beverage made from leaves of the plant Camellia sinensis, has been shown to reduce body weight, alleviate metabolic syndrome, and prevent diabetes and cardiovascular diseases in animal models and humans. Such beneficial effects have generally been observed in most human studies when the level of tea consumption was 3 to 4 cups (600-900 mg tea catechins) or more per day. Green tea is more effective than black tea. In spite of numerous studies, the fundamental mechanisms for these actions still remain unclear. From a review of the literature, we propose that the two major mechanisms are: 1) decreasing absorption of lipids and proteins by tea constituents in the intestine, thus reducing calorie intake; and 2) activating AMPK by tea polyphenols that are bioavailable in the liver, skeletal muscle, and adipose tissues. The relative importance of these two mechanisms depends on the types of tea and diet consumed by individuals. The activated AMPK would decrease gluconeogenesis and fatty acid synthesis and increase catabolism, leading to body weight reduction and MetS alleviation. Other mechanisms and the health relevance of these beneficial effects of tea consumption remain to be further investigated. This article is protected by copyright. All rights reserved.
... Indeed, there is little in vivo evidence to support a role of COMT in relation to clinically meaningful reductions in body weight and adiposity. Hodgson et al. (40), using targeted catecholamine profiling techniques, determined that GTE did not increase concentrations of norepinephrine, which suggests that GTE supplementation may not alter COMT activity. Furthermore, Lorenz et al. (41) determined that the administration of 750 mg EGCG did not impair the in vivo activity of COMT. ...
Article
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Background: Green tea extract (GTE) consumption has been linked to favorable changes in adiposity and bone mineral density (BMD), although it is unknown if these effects are due to green tea catechins or caffeine. The catechol-O-methyltransferase (COMT) genotype may also modify these associations. Objective: We examined the impact of decaffeinated GTE on body composition (using dual-energy X-ray absorptiometry) and obesity-associated hormones. Methods: The Minnesota Green Tea Trial was a 12-mo randomized, double-blind, placebo-controlled clinical trial in 937 postmenopausal women (aged 50-70 y) assigned to receive either GTE containing 843 mg (-)-epigallocatechin-3-gallate or placebo. This substudy was conducted in 121 overweight/obese participants [body mass index (BMI) (kg/m(2)) ≥25.0]. Results: There were no differences in changes in BMI (-0.13 ± 0.11 compared with -0.05 ± 0.11; P = 0.61), total fat mass (-0.30 ± 0.16 compared with -0.12 ± 0.15 kg; P = 0.40), percentage of body fat (-0.15% ± 0.17% compared with -0.15% ± 0.16%; P = 0.99), or BMD (-0.006 ± 0.002 compared with -0.003 ± 0.002 g/cm(2); P = 0.49) over 12 mo between women taking GTE (n = 61) and those taking a placebo (n = 60). Interactions were observed between treatment and time for gynoid percentage of fat (%fat) and tissue %fat. Gynoid %fat increased from baseline to month 12 in the placebo group as baseline BMI increased and decreased over time as baseline BMI increased in the GTE group (P-interaction = 0.02). Tissue %fat increased from baseline to month 12 in the placebo group as baseline BMI increased. In the GTE group, tissue %fat decreased during the intervention as baseline BMI increased (P-interaction = 0.04). No changes were seen in circulating leptin, ghrelin, adiponectin, or insulin concentrations. COMT genotype did not modify the effect of GTE on any variable. Conclusions: Decaffeinated GTE was not associated with overall reductions in adiposity or improvements in BMD in overweight/obese postmenopausal women. However, GTE may be beneficial for reduction in tissue and gynoid %fat in individuals with higher BMI. This clinical trial was registered at www.clinicaltrials.gov as NCT00917735.
... (Martin et al. 2014). Additionally,Hodgson et al. (2013)observed no differences in metabolites indicative of increases in catecholamines following 1 or 7 days of GTE administration. Considering that we concurrently examined the effects of GTE on exercise substrate use and markers of fat catabolism (FFA and glycerol), neither of which were different between treatments, our data did not support an effect of GTE on fuel use in exercising humans. ...
Article
Green tea extract (GTE) ingestion improves glucose homeostasis in healthy and diabetic humans, but the interactive effect of GTE and exercise is unknown. The present study examined the effect of short-term GTE supplementation on the glycemic response to an oral glucose load at rest and following an acute bout of exercise, as well as substrate oxidation during exercise. Eleven sedentary, overweight men with fasting plasma glucose (FPG) ≥5.6 mmol·L⁻¹ (age, 34 ± 13 years; body mass index = 32 ± 5 kg·m⁻²; FPG = 6.8 ± 1.0; mean ± SD) ingested GTE (3× per day, 1050 mg·day-1 total) or placebo (PLA) for 7 days in a double-blind, crossover design. The effects of a 75-g glucose drink were assessed on 4 occasions during both GTE and PLA treatments: On days 1 and 5 at rest, and again following an acute bout of exercise on days 3 and 8. The glycemic response was assessed via an indwelling continuous glucose monitor (CGM) and venous blood draws. At rest, 1-h CGM glucose area under the curve was not different (P > 0.05), but the postexercise response was lower after GTE versus PLA (330 ± 53 and 393 ± 65 mmol·L⁻¹·min⁻¹, main effect of treatment, P < 0.05). The 1-h postprandial peaks in venous blood glucose (8.6 ± 1.6 and 9.8 ± 2.2 mmol·L⁻¹) and insulin (96 ± 59 and 124 ± 68 µIU·ml⁻¹) were also lower postexercise with GTE versus PLA (time × treatment interactions, P < 0.05). In conclusion, short-term GTE supplementation did not affect postprandial glucose at rest; however, GTE was associated with an attenuated glycemic response following a postexercise oral glucose load. These data suggest that GTE might alter skeletal muscle glucose uptake in humans.
... Numerous mechanisms have been proposed for the antiobesity effects of green tea catechins (GTC), including increases in b-oxidation and thermogenesis (12)(13)(14) , as well as reductions in adipocyte differentiation and proliferation, lipogenesis and nutrient absorption (9,(15)(16)(17) , as demonstrated in in vitro, animal and human experiments. Another mechanism by which GTC may reduce body weight or promote weight maintenance is by modifying several hormones associated with energy balance, the post-prandial glycaemic response and satiety. ...
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Background: Green tea extract (GTE) may be involved in a favourable post-prandial response to high-carbohydrate meals. The catechol-O-methyltransferase (COMT) genotype may modify these effects. We examined the acute effects of GTE supplementation on the post-prandial response to a high-carbohydrate meal by assessing appetite-associated hormones and glucose homeostasis marker concentrations in women who consumed 843 mg of (-)-epigallocatechin-3-gallate (EGCG) or placebo capsules for 11-12 months. Methods: Sixty Caucasian post-menopausal women (body mass index ≥ 25.0 kg m(-2) ) were included in a randomised, double-blind feeding study. GTE was consumed with a breakfast meal [2784.0 kJ (665.4 kcal); 67.2% carbohydrate]. Blood samples were drawn pre-meal, post-meal, and every 30 min for 4 h. Participants completed six satiety questionnaires. Results: Plasma leptin, ghrelin and adiponectin did not differ between GTE and placebo at any time point; COMT genotype did not modify these results. Participants randomised to GTE with the high-activity form of COMT (GTE-high COMT) had higher insulin concentrations at time 0, 0.5 and 1.0 h post-meal compared to all COMT groups randomised to placebo. Insulin remained higher in the GTE-high COMT group at 1.5, 2.0 and 2.5 h compared to Placebo-low COMT (P < 0.02). GTE-high COMT had higher insulin concentrations at times 0, 0.5, 1.0, 1.5 and 2.0 h compared to the GTE-low COMT (P ≤ 0.04). Area under the curve measurements of satiety did not differ between GTE and placebo. Conclusions: GTE supplementation and COMT genotype did not alter acute post-prandial responses of leptin, ghrelin, adiponectin or satiety, although it may be involved in post-meal insulinaemic response of overweight and obese post-menopausal women.
... In support of this, we found a significant rise in plasma glycerol in all three protocols, suggesting an increase in lipolysis. 37,47 We also observed a significant rise in circulating span 1 and 2 TCA intermediates (TCAi, citrate, and succinate), indicative of increased TCA cycle flux, after all three endurance protocols. The increase in plasma citrate and succinate most likely resulted from the expansion of the muscle TCAi pool due to activation of oxidative pathways and excessive pyruvate accumulation and their spill over into circulation. ...
Article
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The overall metabolic/energetic stress occurring during an exercise-bout is proposed as the main driving force for long-term training adaptations. Continuous and high-intensity interval exercises (HIIE) are currently prescribed to acquire the muscular and metabolic benefits of aerobic training. We applied 1H NMR-based metabonomics to compare the overall metabolic perturbation and the activation of individual bio-energetic pathways of three popular aerobic exercises matched for effort/strain. Nine men performed continuous, long-interval (3min-bouts), and short-interval (30s-bouts) exercise-bouts under isoeffort conditions. Blood was collected before and after exercise. The multivariate PCA and OPLS-DA models showed a distinct separation of pre- and post-exercise samples in three protocols. The two models did not discriminate the post-exercise overall metabolic profiles of three exercise types. Analysis focused on muscle bio-energetic pathways revealed an extensive up-regulation of carbohydrate-lipid metabolism and TCA-cycle in all three protocols; there were only few differentiations among protocols in post-exercise abundance of molecules when long-interval bouts were performed. In conclusion, continuous and HIIE exercise protocols, when performed with similar effort/strain, induce comparable global metabolic stress despite their marked differences in work-bout intensities. This study highlights the importance of NMR-metabonomics in comprehensive monitoring of metabolic consequences of exercise training in blood of athletes and exercising individuals.
... In another Jówko et al.'s study [19], green tea catechins-treated soccer players were able to perform a higher number of lift repetitions during the muscle endurance test, but none of the analyzed plasma biomarkers was affected by the ingestion of green tea catechins, suggesting that a 640 mg dose was too low to attenuate exercise-induced oxidative stress and muscle damage. Hodgson et al. [24] found that in healthy physically active men, GTE enhanced lipolysis and fat oxidation when compared to placebo, but only under resting conditions, whereas no effect of GTE was seen during exercise. In a more recent study, Sugita et al. [20] have investigated the effects of green tea catechins on oxidative stress metabolites in healthy individuals both at rest and during exercise. ...
Article
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Differential scanning calorimetry (DSC) has been used for the detection of post-exercise changes in blood serum resulting from participation in the CrossFit (CF) training combined with green tea extract (GTE) supplementation. Blood samples from 20 well-trained men were collected at rest, immediately post-exercise and after 1 h of recovery in two trials: first before and second after CF training combined with GTE or placebo administration in the supplemented (S) and control (C) groups, respectively. Selected muscle damage biomarkers have been compared in different phases of the experiment. A significant increase in blood lactate content has been observed post-exercise in both trials in both participants’ groups. The opposite trends have been noted for the C and S groups in creatine kinase (CK) activity changes recorded during the first to the second trial: an increase in CK for the control and a decrease for the supplemented group in all phases of the experiment: pre-exercise, post-exercise and after recovery. In the second trial, all CK values for the S group have been found significantly lower than the corresponding values recorded in the C group. These results suggest a mitigate effect of GTE supplementation on post-training muscle damage. DSC results did not reveal clear effects of training nor GTE supplementation on serum denaturation transition. However, interesting dependences of thermodynamic parameters describing this transition have been observed in different phases of the experiment. Statistically significant negative correlations have been found between post-training VO2max and post-exercise thermodynamic parameters associated with haptoglobin contribution to serum denaturation transition.
... The green-tea catechins include catechin (C), (2)-epicatechin (EC), (2)-epigallocatechin (EGC), (2)-epicatechin-3-gallate (ECG) and (2)-epigallocatechin-3-gallate (EGCG). Out of these, EGCG is a predominant catechin, and has several biological and pharmacological properties (Hodgson et al., 2013). Green tea extract is known to be a potent anti oxidant and anti inflammatory agent which helps in reducing inflammation and stress in liver in dairy cows (Winkler et al., 2015). ...
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The present experiment was carried out on thirty two pregnant Karan Fries (KF) cows. In control group, cows were fed basal diet. In T1 each cow was fed rumen protected choline (RPC) (55g/day), in T2-green tea extract (GTE) (3g/d) and in T3-RPC + GTE (55+3)g/day along with basal diet. The duration of experiment was 30 days before calving to 60 days after parturition. Animals were evaluated on their reproductive performances. Diameter of cervix, uterine horn and service period reduced significantly (p 0.01) in the treatment groups compared to control group. Conception rate was highest for T3 (75 %) followed by T2 (62.5%), T1 (62.5%) and C (50%). There were lesser incidences of reproductive disorders in treatment groups. In conclusion, feeding of RPC and GTE in combination improved reproductive performance during transition period in Karan Fries cows.
... 134 The effects of tea extract on glycolysis are also demonstrated by other studies. [135][136][137] Furthermore, the mitochondrial function and Krebs cycle can be influenced tea extract. 138 Hence, we speculate that tea extract can regulate oocyte maturation via affecting pyruvate metabolism in cumulus cells and oocytes. ...
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Tea is the second most popular beverage in the world and beneficial to health. It has been demonstrated that tea polyphenols can reduce the risk of diseases, such as cancers, diabetes, obesity, Alzheimer's disease, etc. But the knowledge of tea extract on the female germline is limited. Folliculogenesis is a complicated process and prone to be affected by ROS. Tea polyphenols can reduce the accumulation of ROS in folliculogenesis and affect oocyte maturation. Tea extract also influences granulosa cell proliferation and expansion during oocyte growth and maturation. However, the studies about the benefits of tea extract on female germline are few, and the underlying mechanisms are obscure. In the present study, we will mainly discuss the effects of tea extract on ovarian function, oocyte maturation, and the underlying possible mechanisms, and according to the discussion, we suggest that tea extract may have benefits for oocytes at an appropriate dose.
... The higher levels of ␤-hydroxybutyrate found in the exercise group could be accounted for a significant reduction in its levels followed by a subsequent increase towards the end, indicating an initial increase in fat oxidation at the onset of exercise with a delay in fatty acid mobilization and availability later as exercise proceeds [38]. ...
Article
Obesity is one of the independent risk factors for several health problems, leading to metabolic perturbations and for which analytical approaches i.e., “metabolomics” is needed to monitor the underlying metabolic changes. In this study, obesity associated changes were assessed via serum metabolites analysis of obese rats fed on high fat diet. Obese rats were subsequently treated with different functional foods used for obesity management including pomegranate, grapefruit, and red cabbage in parallel to swimming exercise. Serum samples were analyzed using gas chromatography-mass spectrometry (GC-MS) followed by multivariate data analysis to classify samples and determine if such treatments can help revert obesity related metabolic changes back to normal status. Results led to the identification of several novel metabolites biomarkers for obesity related to lipids, amino acids and central tricarboxylic acid (TCA) pathways. Distinct variations in metabolite levels were recorded in obese rats compared to normal ones including l-aspartic, l-alanine, l-glutamine, l-glycine, phenylethanolamine, α-aminobutyric acid and β-hydroxybutyric acid. Metabolomics approach developed herein provides novel insight onto the metabolic disturbances associated with obesity, which will assist in future drug design that can help mitigate against such changes.
... The group differences for changes in lipid-related metabolites were small but consistent with other metabolomics-based studies showing that chronic ingestion of both green tea catechins and caffeine induce subtle effects on fat lipolysis, oxidation, and certain phospholipids and sphingolipids. 48,57,58 The flavonoid supplement contained 60 mg of n3-PUFA (24 mg of docosahexaenoic acid, 36 mg of eicosapentaenoic acid), ∼30% below the mean intake of 86 mg for U.S. adults. 59 Omega-3 PUFAs can be incorporated into the phospholipid bilayer of cell membranes, influencing signaling, membrane fluidity, and lipid microdomain formation, but whether this causes changes in plasma lysolipid, phospholipid, sphingolipid, and ceramide metabolites is unknown. ...
Article
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This study evaluated the effect of ingesting a flavonoid-rich supplement (329 mg/d) on total urine phenolics and shifts in plasma metabolites in overweight/obese female adults using untargeted metabolomics procedures. Participants (N=103, 18-65 y, BMI ≥ 25 kg/m2) were randomized to flavonoid (F) or placebo (P) groups for 12 weeks, with blood and 24-h urine samples collected pre-study, 4- and 12-weeks in a parallel design. Supplements were prepared as chewable tablets, and included vitamin C, wild bilberry fruit extract, green tea leaf extract, quercetin, caffeine, and omega 3 fatty acids. At 4-weeks, urine total phenolics increased 24% in F versus P, with similar changes at 12-weeks (interaction effect, P=0.041). Groups did not differ in markers of inflammation (IL-6, MCP-1, CRP) or oxidative stress (oxLDL, FRAP). Metabolomics data indicated shifts in 63 biochemicals in F versus P, with 70% of from the lipid and xenobiotics super pathways. The largest fold changes in F were measured for three gut-derived phenolics including 3-methoxycatechol sulfate, 3-(3-hydroxyphenyl)propanoic acid sulfate, and 1,2,3-benzenetriol sulfate (interaction effects, p≤0.050). This randomized clinical trial of overweight/obese women showed that 12-weeks ingestion of a mixed flavonoid-nutrient supplement was associated with a corresponding increase in urine total phenolics and gut-derived phenolic metabolites.
... In a more recent RCT with hyperlipidomic subjects, Puer tea extract (38%) was shown to decrease body weight and BMI and improve lipid profiles, but did not affect fasting glucose levels [38]. A metabolomics study with healthy male subjects demonstrated that GTE supplementation (1200 mg catechins and 240 mg caffeine daily) for 7 days increased lipolysis, fat oxidation and citric acid cycle activity under resting conditions without enhancing adrenergic stimulation [39]. The role of caffeine in these studies was inconsistent among the different studies. ...
Article
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Tea, a popular beverage made from leaves of the plant Camellia sinensis, has been studied extensively in recent decades for its beneficial health effects in the prevention of obesity, metabolic syndrome, diabetes, cancer, and other diseases. Whereas these beneficial effects have been convincingly demonstrated in most laboratory studies, results from human studies have not been consistent. Some studies demonstrated that weight reduction, alleviation of metabolic syndrome and risk reduction in diabetes were only observed in individuals who consume 3-4 cups of tea (600-900 mg tea catechins) or more daily. This chapter reviews some of these studies, the possible mechanisms of actions of tea constituents, and the challenges in extrapolating laboratory studies to human situations.
... Previous studies using low to high caffeine doses alone, or caffeine with EGCG have reported variable results regarding effects on fat oxidation [7][8][9][10]23]. Metabolomics-based investigations revealed that ingesting flavonoid-caffeine supplements for 1-12 weeks increased plasma levels of metabolites related to fat metabolism [28,29]. We hypothesized that the acute ingestion of the MFC supplement with a high level of flavonoids (658 mg) would augment fat oxidation compared to placebo. ...
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This randomized, double-blinded, crossover study measured the acute effect of ingesting a mixed flavonoid-caffeine (MFC) supplement compared to placebo (PL) on energy expenditure (EE) and fat oxidation (FATox) in a metabolic chamber with premenopausal women (n = 19, mean ± SD, age 30.7 ± 8.0 year, BMI 25.7 ± 3.4 kg/m2). The MFC supplement (658 mg flavonoids, split dose 8:30, 13:00) contained quercetin, green tea catechins, and anthocyanins from bilberry extract, and 214 mg caffeine. Participants were measured twice in a metabolic chamber for a day, four weeks apart, with outcomes including 22 h EE (8:30–6:30), substrate utilization from the respiratory quotient (RQ), plasma caffeine levels (16:00), and genotyping for the single-nucleotide polymorphism (SNP) rs762551. Areas under the curve (AUC) for metabolic data from the MFC and PL trials were calculated using the trapezoid rule, with a mixed linear model (GLM) used to evaluate the overall treatment effect. The 22 h oxygen consumption and EE were significantly higher with MFC than PL (1582 ± 143, 1535 ± 154 kcal/day, respectively, p = 0.003, trial difference of 46.4 ± 57.8 kcal/day). FATox trended higher for MFC when evaluated using GLM (99.2 ± 14.0, 92.4 ± 14.4 g/22 h, p = 0.054). Plasma caffeine levels were significantly higher in the MFC versus PL trial (5031 ± 289, 276 ± 323 ng/mL, respectively, p < 0.001). Trial differences for 22 h EE and plasma caffeine were unrelated after controlling for age and body mass (r = −0.249, p = 0.139), and not different for participants with the homozygous allele 1, A/A, compared to C/A and C/C (p = 0.50 and 0.56, respectively). In conclusion, EE was higher for MFC compared to PL, and similar to effects estimated from previous trials using caffeine alone. A small effect of the MFC on FATox was measured, in contrast to inconsistent findings previously reported for this caffeine dose. The trial variance for 22 h EE was not significantly related to the variance in plasma caffeine levels or CYP1A2*1F allele carriers and non-carriers.
... GTE supplementation increases resting energy expenditure by about one-third to one-fourth during moderate ET (Auvichayapat et al. 2008). While moderate-intensity cycling exercise stimulates multiple metabolic pathways including lipolysis and glycolysis, GTE supplementation further enhanced lipolysis (increased in glycerol, reduction in triacylglycerol, increased fat oxidation and 3-hydroxybutyrate) produced by cycling exercise alone (Hodgson et al. 2013). Epidemiological and randomized controlled studies indicate that GTE supplementation affects several aspects of energy balance related to the loss of bodyweight and BFP (Chen et al. 2016;Wu et al. 2003). ...
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PurposeGreen tea extract (GTE) supplementation has been proposed to possess anti-inflammatory properties. This study assessed the effects of GTE on endurance training (ET) induced changes on irisin, pro-inflammatory cytokines, adiponectin and anthropometric indices in overweight middle-aged males.Methods Participants were randomly assigned to three groups (n = 15): endurance training + placebo (ET + P), endurance training + green tea extract supplementation (ET + GTE), and no endurance training + placebo (P). The ET intervention consisted of an 8-week training program that included circuit training, fast walking or jogging performed three times/week at a moderate intensity (40–59% of the heart rate reserve). Participants received 500 mg/day GTE using a green tea capsule. Serum concentrations of interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), irisin, adiponectin, and high-sensitivity C-reactive protein (hs-CRP) were measured prior to and after the 8-week training intervention.ResultsBoth exercise interventions decreased IL-6 and hs-CRP (p < 0.05), and increased adiponectin (p < 0.01) levels; changes in these variables were greater in the ET + GTE group compared to the ET + P and P groups (p < 0.01). Irisin concentrations increased only in the ET + GTE group and were different from the ET + P and P groups (p < 0.01). There were no changes in TNF-α concentrations in any of the groups. Both exercise interventions (ET + GTE and ET + P) decreased bodyweight, body mass index (BMI), body fat percentage (BFP), and visceral fat area (VFA) (p < 0.05), with greater changes in these variables occurring in the ET + GTE group compared to ET + P and P groups (p < 0.01).Conclusion The combination of GTE supplementation and ET produces beneficial anti-inflammatory and metabolic effects, which were greater than those produced by ET alone.
... The green-tea catechins include catechin (C), (2)-epicatechin (EC), (2)epigallocatechin (EGC), (2)-epicatechin-3gallate (ECG), and (2)-epigallocatechin-3gallate (EGCG). Out of these, EGCG is a predominant catechin, and has several biological and pharmacological properties (Hodgson et al., 2013). Many researches demonstrated that dietary green tea supplementation tended to increase the overall average weight gain and feed intake of goats, pigs etc. (Ahmed et al., 2015;Tan et al., 2011;Hossain et al., 2012), in contrast, Sayama et al., (2000) and Kaneko et al., (2001) reported reduced body weight and weight gain in rats and broilers. ...
... Green tea intake increased the urinary excretion of several citric acid cycle intermediates more than black tea, which suggests green tea flavanols affect the human oxidative energy metabolism and/or biosynthetic pathways. Hodgson and coworkers showed that GC-MS and LC-MS-based MP of human plasma could enhance our understanding of the mode of action of exercise and GTE beyond the physiological outcomes [120]. Moderate exercise stimulated multiple metabolic pathways including lipolysis, glycolysis, the citric acid cycle, and the adrenergic system. ...
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Low-molecular-weight phytochemicals have health benefits and reduce the risk of diseases, but the mechanisms underlying their activities have remained elusive because of the lack of a methodology that can easily visualize the exact behavior of such small molecules. Recently, we developed an in situ label-free imaging technique, called mass spectrometry imaging, for visualizing spatially-resolved biotransformations based on simultaneous mapping of the major bioactive green tea polyphenol and its phase II metabolites. In addition, we established a mass spectrometry-based metabolic profiling technique capable of evaluating the bioactivities of diverse green tea extracts, which contain multiple phytochemicals, by focusing on their compositional balances. This methodology allowed us to simultaneously evaluate the relative contributions of the multiple compounds present in a multicomponent system to its bioactivity. This review highlights small molecule-sensing techniques for visualizing the complex behaviors of herbal components and linking such information to an enhanced understanding of the functionalities of multicomponent medicinal herbs.
... La réponse métabolique était la même entre les deux types d'apports. D'autres études ont montré qu'un apport en antioxydants, pendant 7 jours avant un effort de 60 minutes à 55% de V O 2 max, provoque une augmentation de lactate, de pyruvate et d'alanine après un effort(Hodgson et al. 2013) , a contrario un apport en antioxydants pendant 10 jours avant un effort en « interval training » de haute intensité n'a provoqué aucun changement sur les concentrations en métabolites(Knab et al. 2013).Renforcer les recherches dans le domaine de l'entraînement et de la santé permet d'étudier les informations métaboliques spécifiques à la population, ce qui est nécessaire pour la prescription personnalisée d'exercice.b) Métabolomique et altitudePeu d'études de métabolomique se sont intéressées à l'effet de l'altitude sur les métabolismes.L'un des effets de l'altitude, exploré par la métabolomique, est l'OPHA, pathologie mortelle résultant d'une ascension rapide à des altitudes supérieures à 2 500 m(Hall et al. 2011;Hackett et Rennie 2002). ...
Thesis
A l’heure actuelle aucun consensus n’existe sur l’utilisation des substrats énergétiques lors d’un exercice en altitude. Certaines études ont montré une utilisation accrue des glucides en altitude comparée à la plaine mais les intensités d’exercices utilisées sont discutables et l’utilisation de méthodes biochimiques traditionnelles ont permis de doser qu’un nombre restreint de molécules. Aujourd’hui grâce à la métabolomique, il est possible d’analyser les variations d’un grand nombre de métabolites simultanément. Le but de cette thèse est d’étudier l’incidence de l’altitude modérée sur l’utilisation des substrats énergétiques à l’effort à l’aide de la métabolomique par résonnance magnétique nucléaire du proton. Des échantillons de plasmas et d’urines ont été collectés lors d’exercices d’endurance en plaine et en altitude modérée chez des sujets non acclimatés. Nos premiers résultats, dans les plasmas, ont montré une baisse de la glycémie et une utilisation accrue des acides aminés ramifiés entre avant et après un exercice d’endurance en altitude, ce qui n’a pas été observé en plaine. Ces résultats ont ensuite été confirmé lors d’un exercice d’endurance jusqu’à épuisement. De plus, nous avons montré que l’utilisation des urines permet de mettre en avant les résultats obtenus dans les plasmas, ce qui est très encourageant pour la compréhension des adaptations métaboliques en altitude par des méthodes non invasives. Pour finir, nous avons utilisé une méthode statistique innovante appelée « analyse en composantes communes et poids spécifiques ». Les résultats ont permis d’observer les variabilités communes entre les paramètres physiologiques mesurés et les variations des métabolites plasmatiques.
... In the study by Jacobs et al. 48 , volunteers ingested two capsules of decaffeinated green tea extract (156 ± 3 mg of green tea extract, 284 ± 6 mg of catechins, and 3 mg of caffeine) with 200 ml of water or placebo (273 ± 25 mg of cellulose) and rested for 2 h while sitting. After this period, they exercised for 30 min in a stationary bicycle at 55% of the VO 2 max. ...
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Aim This review aimed to provide an overview of the publications using metabolomics in research with physical exercises and to demonstrate how researchers have been applying this approach. Methods A systematic search in the databases Web of Science, SCOPUS and PubMed was performed, with the key words: "metabolomics" OR "metabonomics" and with "metabolomics" OR "metabonomics" AND "exercise" in the title or abstract of the articles. The search period was from 2000 to 2016. Forty-four original articles were selected. The studies found were separated into four categories: metabolic responses to physical exercise, supplementation and physical exercise, sports performance, and physical exercise related to diseases. Results It was possible to observe the exponential growth of the use of this approach in Sports and Health Sciences, and the four sub-fields towards which these researches involving exercise are directed, enabling a more comprehensive characterization of different metabolic profiles, as well as their study for identifying new biomarkers related to physical exercise. Conclusions The possibilities of using metabolomics approach are increasing in the fields of Health Sciences, Sports, and Physical Activity. The experimental design of the study is essential to take advantage of this tool and be able to answer questions in the metabolism comprehension.
... The subcategories of black tea, green tea, cocoa, and coffee intake had reported ≥1 metabolite that was replicated (Table 1, Figure 4A, B (20,142,145) and green tea (143,144,147,148,152), respectively. Furthermore, higher levels of the wellknown coffee constituent theobromine and its metabolite 3-methylxanthine (most frequently) were associated with intake of cocoa (153,156,157,159). ...
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Recent advances in metabolomics allow for more objective assessment of contemporary food exposures, which have been proposed as an alternative or complement to self-reporting of food intake. However, the quality of evidence supporting the utility of dietary biomarkers as valid measures of habitual intake of foods or complex dietary patterns in diverse populations has not been systematically evaluated. We reviewed nutritional metabolomics studies reporting metabolites associated with specific foods or food groups; evaluated the interstudy repeatability of dietary biomarker candidates; and reported study design, metabolomic approach, analytical technique(s), and type of biofluid analyzed. A comprehensive literature search of 5 databases (PubMed, EMBASE, Web of Science, BIOSIS, and CINAHL) was conducted from inception through December 2020. This review included 244 studies, 169 (69%) of which were interventional studies (9 of these were replicated in free-living participants) and 151 (62%) of which measured the metabolomic profile of serum and/or plasma. Food-based metabolites identified in ≥1 study and/or biofluid were associated with 11 food-specific categories or dietary patterns: 1) fruits; 2) vegetables; 3) high-fiber foods (grain-rich); 4) meats; 5) seafood; 6) pulses, legumes, and nuts; 7) alcohol; 8) caffeinated beverages, teas, and cocoas; 9) dairy and soya; 10) sweet and sugary foods; and 11) complex dietary patterns and other foods. We conclude that 69 metabolites represent good candidate biomarkers of food intake. Quantitative measurement of these metabolites will advance our understanding of the relation between diet and chronic disease risk and support evidence-based dietary guidelines for global health.
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Physical activity (PA) and exercise are among the most important determinants of health. However, PA is a complex and heterogeneous behavior and the biological mechanisms through which it impacts individuals and populations in different ways are not well understood. Genetics and environment likely play pivotal roles but further work is needed to understand their relative contributions and how they may be mediated. Metabolomics offers a promising approach to explore these relationships. In this review, we provide a comprehensive appraisal of the PA-metabolomics literature to date. This overwhelmingly supports the hypothesis of a metabolomic response to PA, which can differ between groups and individuals. It also suggests a biological gradient in this response based on PA intensity, with some evidence for global longer-term changes in the metabolome of highly active individuals. However, many questions remain and we conclude by highlighting future critical research avenues to help elucidate the role of PA in the maintenance of health and the development of disease.
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Background Metabolomics is a field of omics science that involves the comprehensive measurement of small metabolites in biological samples. It is increasingly being used to study exercise physiology and exercise-associated metabolism. However, the field of exercise metabolomics has not been extensively reviewed or assessed.Objective This review on exercise metabolomics has three aims: (1) to provide an introduction to the general workflow and the different metabolomics technologies used to conduct exercise metabolomics studies; (2) to provide a systematic overview of published exercise metabolomics studies and their findings; and (3) to discuss future perspectives in the field of exercise metabolomics.Methods We searched electronic databases including Google Scholar, Science Direct, PubMed, Scopus, Web of Science, and the SpringerLink academic journal database between January 1st 2000 and September 30th 2020.ResultsBased on our detailed analysis of the field, exercise metabolomics studies fall into five major categories: (1) exercise nutrition metabolism; (2) exercise metabolism; (3) sport metabolism; (4) clinical exercise metabolism; and (5) metabolome comparisons. Exercise metabolism is the most popular category. The most common biological samples used in exercise metabolomics studies are blood and urine. Only a small minority of exercise metabolomics studies employ targeted or quantitative techniques, while most studies used untargeted metabolomics techniques. In addition, mass spectrometry was the most commonly used platform in exercise metabolomics studies, identified in approximately 54% of all published studies. Our data indicate that biomarkers or biomarker panels were identified in 34% of published exercise metabolomics studies.Conclusion Overall, there is an increasing trend towards better designed, more clinical, mass spectrometry-based metabolomics studies involving larger numbers of participants/patients and larger numbers of metabolites being identified.
Article
Green tea catechins (GTCs) are known to improve fat oxidation during fasted, rested and exercise conditions wherein epigallocatechin-3-gallate (EGCG) is thought to be the most pharmacologically active and has been studied extensively. From the available data of randomized controlled trials (RCTs) on EGCG, we carried out a systematic review and meta-analysis to elucidate whether EGCG consumption indeed increase energy expenditure and promote fat oxidation. A systematic review of the literature was conducted using electronic databases (PubMed, Embase, Cochrane Library, CINAHL, JICST, JSTPLUS, and JMEDPLUS and others) and 8 RCTs were included. RCTs were reviewed using preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and methodological quality was assessed. After data extraction, results were aggregated using fixed and random effect approaches and expressed to quantify the relationship between the dose of EGCG for respiratory quotient (RQ), energy expenditure (EE), and rate of fat oxidation (FOX) to compare the EGCG and placebo treatments. The meta-analysis results of verities of studies in term of dose and length of duration revealed that EGCG supplementation provided significant mean difference (MD) when compared with placebo for RQ [MD: -0.02; 95%CI, −0.04 to 0.00; I²=67%; P=.01] and EE [MD: 158.05 kJ/day; 95%CI, 4.72 to 311.38; I²=0%; P=.04] in fixed-effect approach. Changes in FOX did not reach the level of statistical significance. Meta-analyses of EGCG influence on the body mass index (BMI), waist circumference (WC), and total body fat mass (TBFM) were also examined and their impact on the promotion of fat oxidation is reported. Effect of EGCG doses was also systematically reviewed. Finding showed that EGCG intake moderately accelerates energy expenditure, and reduces respiratory quotient. The analyses revealed that the EGCG resulted in difference in respiratory quotient and energy expenditure but the effect on the other measures of energy metabolism was relatively mild. Possibly EGCG alone has the potential to increase metabolic rate at 300 mg dose. Collectively, the outcome support the findings that EGCG has an effect on metabolic parameters. However, the large prospective trials are needed to confirm the findings.
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Stress-induced prolonged inflammation impairs cutaneous wound healing. Exercise may inhibit this effect via an anti-inflammatory mechanism. Our aim was to investigate the effect of moderate exercise on skin wound healing in chronically stressed mice. Mice were trained five times per week on a treadmill or received no training. Mice underwent daily rotational stress from the 6(th) week until euthanasia. During the 8(th) week, two wounds were created in the dorsum and collected 10 days later. A control group only received wounds. Exercise was performed prior to and simultaneous with stress for two weeks or only prior to stress. Stress increased normetanephrine levels 10 days after wounding, resulting in an increased amount of inflammatory cells and reduced expression of inflammatory cytokines as well as angiogenesis, myofibroblast differentiation and matrix deposition. Concomitant exercise and stress potentiated these effects, intensifying the delayed wound contraction. When exercise was performed only prior to stress, however, the mice showed reduced inflammatory cells in granulation tissue 10 days after wounding and improved wound healing compared to animals with exercise and concomitant stress. Moderate exercise in association with stress potentiates the stress effect; however, when exercise was performed prior to stress, wound healing was improved. This article is protected by copyright. All rights reserved.
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Background Decaffeinated green tea extract (dGTE) can increase fat oxidation during leg exercise, but dGTE is unsuitable for many people (e.g., those with injuries/disabilities), and its effects on arm exercise and women are unknown. Methods Eight adults (23–37 years old, 4 women) performed an incremental arm cycle test to measure peak oxygen uptake (VO2peak), followed by four 1-h trials at 50% VO2peak. Subjects were randomly assigned to 650 mg of dGTE or placebo (PLA) for 4 weeks followed by a 4-week washout and crossover trial. Blood samples were obtained pre-exercise and post-exercise for glycerol and free fatty acid analysis. Respiratory gases were collected continuously. Results VO2 showed no differences across trials (0.83–0.89 ± 0.19–0.25L/min, p = 0.460), neither did energy expenditure (264–266 ± 59–77 kcal, p = 0.420) nor fat oxidation (dGTE = 0.11 to 0.12 vs. PLA = 0.10 to 0.09 g/min, p = 0.220). Fat oxidation as percentage of energy expenditure was not different for dGTE vs. PLA (23% ± 12% to 25% ± 11% vs. 23% ± 10% to 21% ± 9%, p = 0.532). Glycerol concentration increased post-exercise in all trials, independent of treatments (pre = 3.4–5.1 ± 0.6–2.6 to post = 7.9–9.8 ± 2.6–3.7 mg/dL, p = 0.867, η² = 0.005 for interaction), as did free fatty acid (3.5–4.8 ± 1.4–2.2 to 7.2–9.1 ± 2.6–4.5 mg/dL, p = 981, η² = 0.000). Conclusion Chronic dGTE supplementation had no effect on lipolysis and fat oxidation during arm cycle exercise in men and women.
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Obesity is one of the independent risk factors for several health problems, leading to metabolic perturbations and for which analytical approaches i.e., “metabolomics” is needed to monitor the underlying metabolic changes. In this study, obesity associated changes were assessed via serum metabolites analysis of obese rats fed on high fat diet. Obese rats were subsequently treated with different functional foods used for obesity management including pomegranate, grapefruit, and red cabbage in parallel to swimming exercise. Serum samples were analyzed using gas chromatography-mass spectrometry (GC-MS) followed by multivariate data analysis to classify samples and determine if such treatments can help revert obesity related metabolic changes back to normal status. Results led to the identification of several novel metabolites biomarkers for obesity related to lipids, amino acids and central tricarboxylic acid (TCA) pathways. Distinct variations in metabolite levels were recorded in obese rats compared to normal ones including L-aspartic, L-alanine, L-glutamine, L-glycine, phenylethanolamine, α-aminobutyric acid and β-hydroxybutyric acid. Metabolomics approach developed herein provides novel insight onto the metabolic disturbances associated with obesity, which will assist in future drugs design that can help mitigate against such changes.
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Introduction: Natural products are obtaining much acceptance as ergogenic aid, not only among athletes but also among the general population including people with excess body fat. Under normal circumstances, an obese person will have the desire and ability to exercise reduced; mainly because they are easily fatigued. Thus, they need to boost their energy production so that they can be more active and healthier. Objective: In this present work, Morinda citrifolia L. leaf extract (MLE) which is believed to possess ergogenic property, was evaluated on its effect on an obese animal model using 1 H-NMR based metabolomics. Material and methods: Rats were fed with high fat diet (HFD) for 12 weeks for obese development. Once this was achieved, all the rats underwent endurance exercise (forced swimming test) every 2 weeks for 8 weeks together with treatment. The time to exhaustion was recorded for each rat. Three different dosages of MLE: 50 mg/kg, 100 mg/kg and 200 mg/kg of body weight were used together with two positive controls: 5 mg/kg caffeine and 100 mg/kg green tea. Blood was collected before and after treatments for metabolomics study. Results: Findings showed that feeding the rats at a dose of 200 mg/kg body weight MLE significantly prolonged the exhaustive swimming time of the rats, and altered the metabolites present in their serum. Discriminating metabolites involved were the product of various metabolic pathways, including carbohydrate, lipids metabolism and energy metabolism. Treatment with 200 mg/kg body weight MLE resulted in significant improvement in the metabolic perturbations where the proximity of the obese exercised treated group to that of normal exercised group in the partial least squares discriminant analysis score plot was observed. Conclusion: The present work demonstrated ergogenic property of MLE based on the improved metabolic perturbation in exercised obese rats.
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Metabolomics, is a comprehensive measure of small metabolites (<1500 Da), which has attracted enormous attention in the last two decades. Metabolomics, in particular investigates unique biochemical fingerprints left behind by specific cellular processes, which represent the metabolic status. Exercise metabolism researchers have started to use this method since 2007. Metabolomics has been used to study the metabolic response to exercise, supplementation and exercise, sport performance and exercise effects in clinical situation. The purpose of this study was to describe metabolomics and its application in exercise metabolism research and to review research literature (from 2007 to the end of 2018). To this end, to facilitate the analysis, Google Scholar and PubMed databases were searched without date restriction. 58 valid studies were identified and divided into 5 groups, as follows: Metabolic response to exercise (27 studies), exercise nutrition (15 studies), sport performance (7 studies), clinical exercise studies (7 studies) and compare athletes metabolome (2 studies). Due to its high capacity, metabolomics can provide a suitable approach for exercise metabolism studies. On the other hand, because metabolites are the end point of physiological pathways, they can provide more reliable and useful information.
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Diabetes mellitus (DM), an ailment caused by unregulated blood sugar levels, can lead to the failure of more than one organ in patients. Currently, blood tests are being conducted in scientific trials to analyse and track blood sugar and ketone levels. In this method, a drop of blood from a pricked finger is placed on a sensitive strip area, which is then pre-inserted into an electronic device to be analysed. However, this method is painful, invasive, and costly, which can be unsafe if not handled properly. Human breath analysis is a rapid and non-invasive approach for detecting different volatile organic compounds (VOCs), which could be indicators of various illnesses. In patients with DM, the body produces excessive amounts of ketones together with acetoacetate, β-hydroxybutyrate (BOHB), and acetone. Acetone is exhaled in the breath. It is produced when the body metabolizes fat, instead of glucose, for energy. Conventional exhalation analysis techniques are based entirely on spectrometric strategies; however, they are becoming increasingly appealing from a clinical point of view with the advancement of gas sensors. This study describes modern-day improvements to semiconductor metal oxide (SMO) gas sensors for the detection of exhaled acetone. Since 2011, all the sensor materials have been used to detect low concentrations of acetone gas (0.1 ppm–20 ppm). Several parameters that affect the performance of the sensor device are mentioned in detail, including the composite materials, morphology, doping, temperature, humidity, acetone concentration, and stability of the sensor. Finally, the applicability of the sensor is discussed.
Chapter
Tea (Camellia sinensis L.) is a popular beverage worldwide, and because of its possible health effects, it has received considerable attention as a medicinal herb. Unfermented green tea constituents show various biological and pharmacological activities. Recently, metabolomic approaches to study the functionality and quality of tea are becoming more common place. One such metabolomic approach, metabolic profiling, can provide information on the relationships between the metabolome and factors such as phenotype or quality. Mass spectrometry (MS) and proton nuclear magnetic resonance (1H-NMR) spectroscopy combined with multivariate statistical analyses are employed for tea metabolomic studies. The highlighted topics are divided into three sections: (1) tea chemical composition, (2) metabolic responses to tea consumption, and (3) biotransformation of dietary tea components. In this chapter, we describe the latest metabolomic techniques applicable to new avenues of tea research.
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Objectives Purpose of this study was to investigate effect of green tea catechins (GTC) on oxidative stress metabolites at resting and during exercise in healthy human including responses to fat metabolism, blood lactate concentration, and rating of perceived exertion (RPE). Methods In a paralleled, cross-over randomized controlled study design 16 trained male gymnastic students were randomly divided into two groups as rest group (n=8; GTC-NEX), received an single dose of 780 mg GTC with water without exercise, and an exercise group (n=8; GTC-EX), who received similar dose of GTC with exercise, and followed by a cross-over study with similar exercise regime as placebo group (PL-EX) with water only. Blood samples were collected at initial, after 60 and 120 min of GTC intake, and oxidative stress blood biomarkers d-ROMs, BAP, and urinary 8-OHdG, 8-OHdG/CRE, and blood lactate concentrations were analyzed. During the cycle ergometer exercise VO2max, VO2, VCO2 and RER were measured from the respiratory breath gas sample collected at low, moderate and high intensities of exercise, and amount of fat burning and sugar consumption level were calculated. ANOVA was used for statistical significance (p<0.05) in between the groups and among the group. Results and discussion Post-exercise oxidative stress metabolite BAP and d-ROMs levels were found significant (P<0.0001) in both PL-EX and GTC-EX groups, and recovered to pre-exercise levels after recovery period. The d-ROMs level showed no significant difference from baseline upon GTC intake followed by resting and resting recovery period in GTC-NEX group. BAP levels were significant upon GTC intake followed by resting (P=0.04), and after resting recovery period (P=0.0006) in GTC-NEX group. Urinary 8-OHdG levels were also significant (P<0.005) for all groups after recovery period. Significance difference could be noticed between resting BAP/d-ROMs and exercise-induced BAP/d-ROMs ratios (P= 0.022) after 60 min of GTC intake, as well as resting 8-OHdG and exercise induced 8-OHdG levels (P=0.004) after recovery period. Oxidative potentials were higher when exercise was performed at low to moderate intensity, accompanied with lower blood lactate concentration and higher amount of fat oxidation. Conclusions Our results indicate that single dose consumption of GTC have influence on oxidative stress biomarker when compared between GTC-NEX and GTC-EX groups, which could be beneficial for oxidative metabolism at rest and during the exercise, possibly through COMT mechanism as cited most in previous studies.
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In human nutritional science progress has always depended strongly on analytical measurements for establishing relationships between diet and health. This field has undergone significant changes as a result of the development of NMR and mass spectrometry methods for large scale detection, identification and quantification of metabolites in body fluids. This has allowed systematic studies of the metabolic fingerprints that biological processes leave behind, and has become the research field of metabolomics. As a metabolic profiling technique, NMR is at its best when its unbiased nature, linearity and reproducibility are exploited in well-controlled nutritional intervention and cross-sectional population screening studies. Although its sensitivity is less good than that of mass spectrometry, NMR has maintained a strong position in metabolomics through implementation of standardisation protocols, hyphenation with mass spectrometry and chromatographic techniques, accurate quantification and spectral deconvolution approaches, and high-throughput automation. Thus, NMR-based metabolomics has contributed uniquely to new insights into dietary exposure, in particular by unravelling the metabolic fates of phytochemicals and the discovery of dietary intake markers. NMR profiling has also contributed to the understanding of the subtle effects of diet on central metabolism and lipoprotein metabolism. In order to hold its ground in nutritional metabolomics, NMR will need to step up its performance in sensitivity and resolution; the most promising routes forward are the analytical use of dynamic nuclear polarisation and developments in microcoil construction and automated fractionation.
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Improvement in dietary habits and regular exercise is considered to be effective in preventing and/or reducing obesity and lifestyle-related diseases. The aim of this study was to analyze the effects of the combination of regular exercise and tea catechins intake on energy expenditure in humans. Fourteen healthy male subjects of 26 to 42 years of age received either a test beverage containing tea catechins or a control beverage without tea catechins for 2 months period; during this period they also engaged in treadmill exercise at a pace of 5 km/hr for 30 min 3 times a week. Energy expenditure in a sedentary condition or during the treadmill exercise was measured after 2 months by indirect colorimetry. Fat utilization for energy expenditure under both sedentary and exercising conditions was significantly increased by the combination of regular exercise and tea catechins intake compared to that by exercise alone.
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The long-term ingestion of tea catechins has been reported to reduce body fat. The aim of this study was to investigate the effect of the long-term ingestion of tea catechins on postprandial energy expenditure and dietary fat oxidation. Twelve healthy men aged 27-48 years participated in the study. The subjects consumed 350 ml of a test beverage/day that contained either a high dose of catechin (592.9 mg) or a low dose of catechin (77.7 mg) for a period of 12 weeks. Respiratory analyses were conducted before and at 4, 8, and 12 weeks during the test period, in which oxygen consumption and the excretion of 13CO2 were monitored over 8 hr after a single ingestion of a test meal containing 13C labeled triglyceride. The excretion of 13CO2 in the high dose catechin group (the HC group) was significantly increased at 4 and 12 weeks of the test period compared to that for the low dose catechin group (the LC group) (p < 0.05), and this elevation persisted at 8.9% at week 0 to 12.9% at week 12. Dietary induced thermogenesis (DIT), defined as an increased energy expenditure from the fasting baseline for 8 hr after the single ingestion of a test meal, was significantly higher in the HC group at 8 and 12 weeks compared to that in the LC group (p < 0.05) with elevation to 90.3 kcal at week 12 from 51.4 kcal at week 0. In conclusion, enhanced dietary fat oxidation and an increased DIT may play an important role in the mechanism of the anti-obesity effect of tea catechins.
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Green tea is made from the leaves of the Camellia sinensis L plant, which is rich in polyphenol catechins and caffeine. There is increasing interest in the potential role of green tea extract (GTE) in fat metabolism and its influence on health and exercise performance. A number of studies have observed positive effects of GTE on fat metabolism at rest and during exercise, following both shorter and longer term intake. However, overall, the literature is inconclusive. The fact that not all studies observed effects may be related to differences in study designs, GTE bioavailability, and variation of the measurement (fat oxidation). In addition, the precise mechanisms of GTE in the human body that increase fat oxidation are unclear. The often-cited in vitro catechol-O-methyltransferase mechanism is used to explain the changes in substrate metabolism with little in vivo evidence to support it. Also, changes in expression of fat metabolism genes with longer term GTE intake have been implicated at rest and with exercise training, including the upregulation of fat metabolism enzyme gene expression in the skeletal muscle and downregulation of adipogenic genes in the liver. The exact molecular signaling that activates changes to fat metabolism gene expression is unclear but may be driven by PPAR-γ coactivator 1-α and PPARs. However, to date, evidence from human studies to support these adaptations is lacking. Clearly, more studies have to be performed to elucidate the effects of GTE on fat metabolism as well as improve our understanding of the underlying mechanisms.
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• Contemporary stable isotope methodology was applied in combination with muscle biopsy sampling to accurately quantify substrate utilisation and study the regulation of muscle fuel selection during exercise. • Eight cyclists were studied at rest and during three consecutive 30 min stages of exercise at intensities of 40, 55 and 75 % maximal workload (Wmax). A continuous infusion of [U-13C]palmitate and [6,6-2H2]glucose was administered to determine plasma free fatty acid (FFA) oxidation and estimate plasma glucose oxidation, respectively. Biopsy samples were collected before and after each exercise stage. • Muscle glycogen and plasma glucose oxidation rates increased with every increment in exercise intensity. Whole-body fat oxidation increased to 32 ± 2 kJ min−1 at 55 % Wmax, but declined at 75 % Wmax (19 ± 2 kJ min−1). This decline involved a decrease in the oxidation rate of both plasma FFA and triacylglycerol fat sources (sum of intramuscular plus lipoprotein-derived triacylglycerol), and was accompanied by increases in muscle pyruvate dehydrogenase complex activation and acetylation of the carnitine pool, resulting in a decline in muscle free carnitine concentration. • We conclude that the most likely mechanism for the reduction in fat oxidation during high-intensity exercise is a downregulation of carnitine palmitoyltransferase I, either by this marked decline in free carnitine availability or by a decrease in intracellular pH.
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Green tea is manufactured from the leaves of the plant Camellia sinensis Theaceae and has been regarded to possess anti-cancer, anti-obesity, anti-atherosclerotic, anti-diabetic, anti-bacterial, and anti-viral effects. Many of the beneficial effects of green tea are related to the activities of (-)-epigallocatechin gallate (EGCG), a major component of green tea catechins. For about 20 years, we have engaged in studies to reveal the biological activities and action mechanisms of green tea and EGCG. This review summarizes several lines of evidence to indicate the health-promoting properties of green tea mainly based on our own experimental findings.
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(-)-Epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, has been shown to prevent the development of obesity in rodent models. Here, we examined the effect of EGCG on markers of fat oxidation in high fat-fed C57bl/6J mice. High fat-fed mice treated with 0.32% dietary EGCG for 16 weeks had reduced body weight gain and final body weight (19.2% and 9.4%, respectively) compared to high fat-fed controls. EGCG-treatment decreased fasting blood glucose, plasma insulin, and insulin resistance by 18.5%, 25.3%, and 33.9%, respectively. EGCG treatment also reduced markers of obesity-related fatty liver disease in high fat-fed mice. Gene expression analysis of skeletal muscle showed that EGCG increased mRNA levels of nuclear respiratory factor (nrf)1, medium chain acyl coA decarboxylase (mcad), uncoupling protein (ucp)3, and peroxisome proliferator responsive element (ppar)α by 1.4-1.9-fold compared to high fat-fed controls. These genes are all related to mitochondrial fatty acid oxidation. In addition, EGCG increased fecal excretion of lipids in high fat-fed mice. In summary, it appears that EGCG modulates body weight gain in high fat-fed mice both by increasing the expression of genes related fat oxidation in the skeletal muscle and by modulating fat absorption from the diet.
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When considering methylxanthines and human health, it must be recognized that in many countries most caffeine is consumed as coffee. This is further confounded by the fact that coffee contains many bioactive substances in addition to caffeine; it is rich in phenols (quinides, chlorogenic acid, and lactones) and also has diterpenes (fatty acid esters), potassium, niacin, magnesium, and the vitamin B(3) precursor trigonelline. There is a paradox as consumption of either caffeine or caffeinated coffee results in a marked insulin resistance and yet habitual coffee consumption has repeatedly been reported to markedly reduce the risk for type 2 diabetes. There is strong evidence that caffeine reduces insulin sensitivity in skeletal muscle and this may be due to a combination of direct antagonism of A(1) receptors and indirectly β-adrenergic stimulation as a result of increased sympathetic activity. Caffeine may also induce reduced hepatic glucose output. With the exception of bone mineral, there is little evidence that caffeine impacts negatively on other health issues. Coffee does not increase the risk of cardiovascular diseases or cancers and there is some evidence suggesting a positive relationship for the former and for some cancers, particularly hepatic cancer.
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The thermogenic and metabolic properties of capsinoids appear to mimic those of the more pungent sister compound capsaicin. However, few data exist on how capsinoid ingestion affects energy expenditure in humans and no data exist on its interaction with exercise. We aimed to determine how ingestion of capsinoids affected energy expenditure, lipid oxidation and blood metabolites at rest and during moderate intensity exercise. Twelve healthy young men (age = 24.3 +/- 3 yr, BMI = 25.5 +/- 1.7 kg.m-2) were studied on two occasions in a double-blind design following ingestion of either placebo or 10 mg of purified capsinoids at rest, after 90 min of cycling at 55% VO2 peak, and for 30 min into recovery. Subjects ingested the capsules 30 min prior to exercise. At rest, following ingestion of capsinoids, we observed increases in VO2 and plasma norepinephrine levels, and decreases in concentrations of serum free fatty acids, plasma glycerol and the respiratory exchange ratio (all P < 0.05). At exercise onset, we observed a blunted accumulation of blood lactate with capsinoid ingestion vs. placebo (P < 0.05). There were no other significant differences between the conditions during or post-exercise. The ingestion of 10 mg of capsinoids increased adrenergic activity, energy expenditure, and resulted in a shift in substrate utilization toward lipid at rest but had little effect during exercise or recovery. The changes we observed confirm previous data on the thermogenic and metabolic effects of capsinoids at rest and further promote its potential role as an adjunct weight loss aid, in addition to diet and exercise.
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Animal evidence indicates that green tea may modulate insulin sensitivity, with epigallocatechin-3-gallate (EGCG) proposed as a likely health-promoting component. The purpose of this study was to investigate the effect of dietary supplementation with EGCG on insulin resistance and associated metabolic risk factors in man. Overweight or obese male subjects, aged 40-65 years, were randomly assigned to take 400 mg capsules of EGCG (n 46) or the placebo lactose (n 42), twice daily for 8 weeks. Oral glucose tolerance testing and measurement of metabolic risk factors (BMI, waist circumference, percentage body fat, blood pressure, total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG) was conducted pre- and post-intervention. Mood was evaluated weekly using the University of Wales Institute of Science and Technology mood adjective checklist. EGCG treatment had no effect on insulin sensitivity, insulin secretion or glucose tolerance but did reduce diastolic blood pressure (mean change: placebo - 0.058 (se 0.75) mmHg; EGCG - 2.68 (se 0.72) mmHg; P = 0.014). No significant change in the other metabolic risk factors was observed. The EGCG group also reported feeling in a more positive mood than the placebo group across the intervention period (mean score for hedonic tone: EGCG, 29.11 (se 0.44); placebo, 27.84 (se 0.46); P = 0.048). In conclusion, regular intake of EGCG had no effect on insulin resistance but did result in a modest reduction in diastolic blood pressure. This antihypertensive effect may contribute to some of the cardiovascular benefits associated with habitual green tea consumption. EGCG treatment also had a positive effect on mood. Further studies are needed to confirm the findings and investigate their mechanistic basis.
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Single-dose oral administration of 100 mg caffeine increased the resting metabolic rate of both lean and postobese human volunteers by 3-4% (p less than 0.02) over 150 min and improved the defective diet-induced thermogenesis observed in the postobese subjects. Measurements of energy expenditure (EE) in a room respirometer indicate that repeated caffeine administration (100 mg) at 2-h intervals over a 12-h day period increased the EE of both subject groups by 8-11% (p less than 0.01) during that period but had no influence on the subsequent 12-h night EE. The net effect was a significant increase (p less than 0.02) in daily EE of 150 kcal in the lean volunteers and 79 kcal in the postobese subjects. Caffeine at commonly consumed doses can have a significant influence on energy balance and may promote thermogenesis in the treatment of obesity.
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We assessed the effect of ingestion of green tea (GT) extract along with a low-energy diet (LED) on resting energy expenditure (REE), substrate oxidation and body weight as GT has been shown to increase energy expenditure and fat oxidation in the short term in both animals and people. Forty-six overweight women (BMI 27 center dot 6 (sd 1 center dot 8) kg/m(2)) were fed in energy balance from day 1 to day 3, followed by a LED with GT (1125 mg tea catechins +225 mg caffeine/d) or placebo (PLAC) from day 4 to day 87. Caffeine intake was standardised to 300 mg/d. Energy expenditure was measured on days 4 and 32. Reductions in weight (4 center dot 19 (sd 2 center dot 0) kg PLAC, 4 center dot 21 (sd 2 center dot 7) kg GT), BMI, waist:hip ratio, fat mass and fat-free mass were not statistically different between treatments. REE as a function of fat-free mass and fat mass was significantly reduced over 32 d in the PLAC group (P < 0 center dot 05) but not in the GT group. Dietary restraint increased over time (P < 0 center dot 001) in both groups, whereas disinhibition and general hunger decreased (P < 0 center dot 05). The GT group became more hungry over time and less thirsty, and showed increased prospective food consumption compared with PLAC (P < 0 center dot 05). Taken together, the ingestion of GT along with a LED had no additional benefit for any measures of body weight or body composition. Although the decrease in REE as a function of fat-free mass and fat mass was not significant with GT treatment, whereas it was with PLAC treatment, no significant effect of treatment over time was seen, suggesting that a robust limitation of REE reduction during a LED was not achieved by GT.
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An aqueous methanol extract from green tea showed potent acetyl-CoA carboxylase inhibitory activity. An active compound was isolated from the extract and identified as (-)-epigallocatechin gallate by instrumental analyses, The IC50 value of (-)-epigallocatechin gallate was 3.1 x 10(-4) M. Among tea catechins and related compounds, nearly equal activity was found in(-)-epigallocatechin gallate and (-)epicatechin gallate, whereas (+)-catechin, (-)-epicatechin, (-)-epigallocatechin, gallic acid and methyl gallate each had no inhibitory activity. These results indicate that the 3-O-gallate group of the catechin structure was necessary for this activity. (-)-Epigallocatechin gallate inhibited triglyceride accumulation in 3T3-L1 cells at a concentration of 1.0 x 10(-7) M or higher.