ArticleLiterature Review

Medium-chain triglycerides: An update

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

A review of the literature on the medical and nutritional use of medium-chain triglycerides (MCTs) since 1970 is presented with additional discussions on the various modifications and applications of the MCTs in the synthesis of certain structured lipids. The metabolism of MCTs in the liver and extrahepatic tissues is discussed along with further documentation of the use of MCTs in malabsorption and hyperlipidemia cases. Recent applications of MCTs and modified MCTs in hyperalimentation, deficiency in the carnitine system, epilepsy, obesity, and other special areas of application are cited. The use of medium-chain monodiglycerides for dissolving cholesterol gallstones is presented. The contraindications for the use of MCTs in ketosis, acidosis, and cirrhosis are also discussed. Suggestions for use of MCTs in a variety of medical and nutritional applications are presented.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... By definition, MCFAs generally refer to saturated FAs, with a chain length of 6-12 carbons, naturally occurring in some vegetable oils (coconut and palm kernel oils) and milk fat (5,6). Typical medium-chain TAG (MCT) is mainly composed of caprylic acid (8:0) and capric acid (10:0). ...
... MCFA-enriched oils, such as coconut oil and palm kernel oil or MCT, are often added to infant formulas as a source of MCFAs to facilitate fat absorption and the growth of infants, especially in formulas designed for low birth weight or preterm infants (13,14). MCFAs are an important source of energy because their properties during the processes of digestion, absorption, and metabolism are different from those of long-chain fatty acids (LCFAs) (6,15). It has been well documented that MCFAs are more easily absorbed and oxidized for energy than LCFAs since they are primarily absorbed directly to the liver via the portal vein and rapidly transferred independently of the carnitine shuttle system to the mitochondria (6). ...
... MCFAs are an important source of energy because their properties during the processes of digestion, absorption, and metabolism are different from those of long-chain fatty acids (LCFAs) (6,15). It has been well documented that MCFAs are more easily absorbed and oxidized for energy than LCFAs since they are primarily absorbed directly to the liver via the portal vein and rapidly transferred independently of the carnitine shuttle system to the mitochondria (6). The addition of MCT to infant formula could facilitate better absorption of lipids (16). ...
Article
Full-text available
Human breastmilk, the ideal food for healthy infants, naturally contains a high concentration of medium-chain fatty acids (MCFAs, about 15% of total fatty acids). MCFAs are an important energy source for infants due to their unique digestive and metabolic properties. MCFA-enriched oils are widely used in an infant formula, especially the formula produced for preterm infants. Recently, there has been a growing interest in the triglyceride structure of MCFAs in human milk, their metabolism, and their effects on infant health. This study summarized the MCFA composition and structure in both human milk and infant formula. Recent studies on the nutritional effects of MCFAs on infant gut microbiota have been reviewed. Special attention was given to the MCFAs digestion and metabolism in the infants. This paper aims to provide insights into the optimization of formulations to fulfill infant nutritional requirements.
... Hermetia illucens larvae fat is characterised by saturated medium-chain fatty acids (MCFA) (C6:0-C12:0), of which lauric acid (C12:0) accounts for the largest proportion of more than 50% of total fatty acids [13][14][15]. Medium-chain-fatty acids are regarded as readily digestible, since they do not require bile acidmediated micelle formation to emulsify in the aqueous phase of digesta, but are absorbed by simple passive diffusion and thus an immediate energy source e.g. for enterocytes [12,16,17]. Consequently, positive effects on nutrient digestibility and intestinal morphology may result, which need to be investigated. ...
... On the one hand, HI larvae fat is known to contain MCFA and so the lauric acid content in the present finisher diets increased almost thirtyfold and twelvefold from 0 to 100% HI larvae fat ( Table 3). As already stated, MCFA do not require bile acid-mediated micelle formation to be soluble in the aqueous phase [12], are passively absorbed and thus an immediate energy source for enterocytes and are therefore regarded readily available for the animal [12,16]. On the other hand, this advantageous effect of MCFA and lauric acid may have been counteracted by the high share of longer saturated FA, which more than doubled in the finisher feeds from 0 to 100% HI larvae fat. ...
... In the present study, the ratio of unsaturated to saturated FA in the diet has at least halved over all feeding phases within protein sources from groups with 0 larvae fat to 100% larvae fat. Contrary to the aforementioned observations of previous studies [12,16,18], we have neither seen an increase in digestibility due to lauric acid or a decrease due to saturated FA in 100% HI larvae fat groups, nor an improvement in the 50 L groups. In future research projects, however, it is worth investigating digestibility in the starter phase as well, to assess potential differences in this crucial phase of broiler production. ...
Article
Full-text available
Background The possibility of partially replacing soybean meal (SBM) with Hermetia illucens (HI) defatted larvae meal in broiler nutrition has frequently been suggested. For sustainability reasons, however, the larvae fat produced during defatting should also be used and could be particularly beneficial regarding gut health due to its fatty acid composition. To evaluate the suitability of HI larvae as protein and fat source, a 2 × 3 factorial arrangement with two types of protein, i.e. SBM (S) or SBM and 15% of its crude protein replaced by HI larvae meal (L), and three levels of fat sources, namely 0 (0 L), 50% (50 L) or 100% HI larvae fat (100 L) at the expense of soybean oil was applied. Results In the starter phase, an interaction showed higher body weight (BW), average daily gain (ADG) and improved feed conversion ratio (FCR) if 50% or 100% HI larvae fat was fed with HI larvae meal. Moreover, BW, ADG and FCR improved when feeding HI larvae meal as protein source. Additionally, we observed an increased average daily feed intake in the grower, finisher, and overall phase in the L groups and an improved FCR in 0 L compared to 50 L groups during the overall period. Regarding apparent ileal digestibility, HI larvae meal feeding increased dry matter, organic matter, and fat digestibility. Feeding HI larvae meal as protein source decreased the concentrations of agmatine, spermidine, spermine and ammonia in the caecal digesta, whereas fat source affected agmatine with higher concentrations in 50 L compared to 0 L in the colonic digesta. In contrast, caecal ethanolamine concentrations increased in HI larvae meal groups compared to SBM. Caecal butyric acid concentrations decreased with HI larvae meal feeding. An interaction was found for the jejunal villus area, being higher in L + 100 L compared to S + 100 L. Furthermore, L groups had greater villus width. Conclusions A partial replacement of SBM with HI larvae meal and soybean oil with HI larvae fat in broiler diets without impairing animal performance or gut health seems possible. Feeding HI larvae meal affected broiler performance positively in the starter phase and improved apparent ileal digestibility.
... Deemed to be smaller in size and hydrophilic in nature because of its shorter chain length, MCFA is delivered directly to the liver via the hepatic portal vein to undergo the beta-oxidation process in the mitochondria. As a result, its rapid metabolism leads to the production of ketones bodies such as acetoacetate, acetone, beta-hydroxybutyrate that serves as an instantaneous source of energy to the body, thereby rendering it to have a lesser tendency to be resynthesised to form triacylglycerol that has that tendency to be accumulated as body fat (Bach and Babayan 1982;Papamandjaris, MacDougall, and Jones 1998). On the other hand, the metabolism of LCFA is somewhat different from MCFA. ...
... Classification of MCT by the USFDA originated from the production of the commercialization of the first MCT oil which contains only C8 and C10 fatty acid. Nevertheless, a study conducted by Bach and Babayan (1982) to assess the metabolism of saturated fatty acid in the liver proposed that C12 fatty acid to be classified as MCFA. Based on his finding, C12 fatty acid has similar properties as C8 and C10 but distinctly different from LCFA (Bach and Babayan 1982). ...
... Nevertheless, a study conducted by Bach and Babayan (1982) to assess the metabolism of saturated fatty acid in the liver proposed that C12 fatty acid to be classified as MCFA. Based on his finding, C12 fatty acid has similar properties as C8 and C10 but distinctly different from LCFA (Bach and Babayan 1982). C8, C10 and C12 are metabolized in the liver and possesses antimicrobial properties which is not evidence in LCFA. ...
Article
Structured lipid is a type of modified form of lipid that is “fabricated” with the purpose to improve the nutritional and functional properties of conventional fats and oils derived from animal and plant sources. Such healthier choice of lipid received escalating attention from the public for its capability to manage the rising prevalence of metabolic syndrome. Of which, medium-chain triacylglycerol (MCT) and medium-and long-chain triacylglycerol (MLCT) are the few examples of the “new generation” custom-made healthful lipids which are mainly composed of medium chain fatty acid (MCFA). MCT is made up exclusively of MCFA whereas MLCT contains a mixture of MCFA and long chain fatty acid (LCFA), respectively. Attributed by the unique metabolism of MCFA which is rapidly metabolized by the body, MCFA and MCT showed to acquire multiple physiological and functional properties in managing and reversing certain health disorders. Several chemically or enzymatically oils and fats modification processes catalyzed by a biological or chemical catalyst such as acidolysis, interesterification and esterification are adopted to synthesis MCT and MLCT. With their purported health benefits, MCT and MLCT are widely being used as nutraceutical in food and pharmaceutical sectors. This article aims to provide a comprehensive review on MCT and MLCT, with an emphasis on the basic understanding of its structures, properties, unique metabolism; the current status of the touted health benefits; latest routes of production; its up-to-date applications in the different food systems; relevant patents filed and its drawbacks
... Despite potential advantages, the ketogenic diet has multiple adverse effects. During the first four-week period, nausea, vomiting, and diarrhea are particularly common with the medium-chain triglyceride diet [16][17][18], posing a risk for acute kidney injury, hyponatremia, hypomagnesemia, hypercalciuria, hyperuricemia, and metabolic acidosis [19][20][21]. Long-term adverse effects of the ketogenic diet, including osteopenia, risk of bone fractures, alterations in vitamin D levels, are well reported [22][23][24]. ...
... Long-term adverse effects of the ketogenic diet, including osteopenia, risk of bone fractures, alterations in vitamin D levels, are well reported [22][23][24]. Increased risk for kidney stones is well described in patients using the ketogenic diet for over a 2 year period [17,20,25,26], with complications such as obstructive uropathy, acute kidney injury, and chronic kidney disease [27][28][29]. ...
... The incidence of kidney stones among patients on the ketogenic diet ranges from 3% to 10% [20,30,31], compared to one in several thousand in the general population [17,24]. We performed a meta-analysis on the incidence and characteristics of kidney stones in patients on the ketogenic diet to better understand the kidney stones' burden and pathophysiology in this population. ...
Article
Full-text available
Very-low-carbohydrate diets or ketogenic diets are frequently used for weight loss in adults and as a therapy for epilepsy in children. The incidence and characteristics of kidney stones in patients on ketogenic diets are not well studied. Methods: A systematic literature search was performed, using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from the databases’ inception through April 2020. Observational studies or clinical trials that provide data on the incidence and/or types of kidney stones in patients on ketogenic diets were included. We applied a random-effects model to estimate the incidence of kidney stones. Results: A total of 36 studies with 2795 patients on ketogenic diets were enrolled. The estimated pooled incidence of kidney stones was 5.9% (95% CI, 4.6–7.6%, I2 = 47%) in patients on ketogenic diets at a mean follow-up time of 3.7 +/− 2.9 years. Subgroup analyses demonstrated the estimated pooled incidence of kidney stones of 5.8% (95% CI, 4.4–7.5%, I2 = 49%) in children and 7.9% (95% CI, 2.8–20.1%, I2 = 29%) in adults, respectively. Within reported studies, 48.7% (95% CI, 33.2–64.6%) of kidney stones were uric stones, 36.5% (95% CI, 10.6–73.6%) were calcium-based (CaOx/CaP) stones, and 27.8% (95% CI, 12.1–51.9%) were mixed uric acid and calcium-based stones, respectively. Conclusions: The estimated incidence of kidney stones in patients on ketogenic diets is 5.9%. Its incidence is approximately 5.8% in children and 7.9% in adults. Uric acid stones are the most prevalent kidney stones in patients on ketogenic diets followed by calcium-based stones. These findings may impact the prevention and clinical management of kidney stones in patients on ketogenic diets.
... The smaller molecular weight of MCTs than long-chain triglycerides (LCTs) facilitates the action of pancreatic lipase and thus enables MCTs to be hydrolyzed both faster and more completely than LCTs with a reduction in stool lipid excretion (26,66). Notably, a 40% contribution of MCT to fat intake was reported to enhance fat absorption by about 10% relative to formulae based on LCTs (67), while the absorption of calcium, magnesium and amino acids has also been reported to be enhanced when the diet contains MCTs, particularly in infants (66,68). ...
... The smaller molecular weight of MCTs than long-chain triglycerides (LCTs) facilitates the action of pancreatic lipase and thus enables MCTs to be hydrolyzed both faster and more completely than LCTs with a reduction in stool lipid excretion (26,66). Notably, a 40% contribution of MCT to fat intake was reported to enhance fat absorption by about 10% relative to formulae based on LCTs (67), while the absorption of calcium, magnesium and amino acids has also been reported to be enhanced when the diet contains MCTs, particularly in infants (66,68). ...
... Although an increase in the energy density of foods and thus provision of adequate energy in diet is often achieved by increasing the lipid content (26), in children with severe malnutrition, who are most in need of additional dietary energy, there is disturbed lipid metabolism (26). MCT component of peptide-based formulas is important in this regard, given that MCTs are considered a preferable source of abundant and rapidly available energy in case of increased energy needs [i.e., undernourished patients after major surgery or children during normal or retarded growth; (66,68,69)]. ...
Article
Full-text available
This review focuses on nutritional support in malnourished children with compromised gastrointestinal function addressing the interplay between malnutrition and gastrointestinal dysfunction, and the specific role of peptide-based enteral therapy in pediatric malnutrition. Malnutrition is associated with impaired gut functions such as increased intestinal permeability, malabsorption, and diarrhea, while pre-existing functional gastrointestinal disorders may also lead to malnutrition. Presence of compromised gastrointestinal function in malnourished children is critical given that alterations such as malabsorption and increased intestinal permeability directly interfere with efficacy of nutritional support and recovery from malnutrition. Appropriate nutritional intervention is the key step in the management of malnutrition, while alterations in gastrointestinal functions in malnourished children are likely even in those with mild degree malnutrition. Therefore, nutritional therapy in children with compromised gastrointestinal function is considered to involve gut-protective interventions that address the overlapping and interacting effects of diarrhea, enteropathy and malnutrition to improve child survival and developmental potential in the long-term. Peptide-based enteral formulas seem to have clinical applications in malnourished children with compromised gastrointestinal function, given their association with improved gastrointestinal tolerance and absorption, better nitrogen retention/ balance, reduced diarrhea and bacterial translocation, enhanced fat absorption, and maintained/restored gut integrity as compared with free amino acid or whole-protein formulas.
... Experiments with radioactive isotopes in 1951 showed that fatty acids less than C12:0 were rarely found in the thoracic duct lymphatics, but were mostly in the portal vein (17). It was later confirmed in animal experiments that there were no adverse effects, even when administered in large doses (3), and clinical studies on humans began. ...
... This might be due to a temporary increase in cholesterol biosynthesis, since acetyl CoA is also the starting material for the biosynthesis of cholesterol. Under conditions such as fasting, starvation, and continuous intake of low-carbohydrate diet, lipolysis increases free fatty acids in the blood, and in addition, NAD+ increases in hepatocytes, which in turn increases ketone body synthase (17). On the other hand, due to the lack of pyruvate and alpha-ketoglutarate derived from glycolysis system by restricting carbohydrates, the reaction with acetyl CoA is reduced. ...
... On the other hand, due to the lack of pyruvate and alpha-ketoglutarate derived from glycolysis system by restricting carbohydrates, the reaction with acetyl CoA is reduced. As a result, fatty acid-derived acyl CoA is not sufficiently metabolized by the tricarboxylic acid (TCA) cycle and is allocated to ketone body production (17). When an individual ingests more MCTs than the TCA cycle and respiratory chain can process the acetyl CoA produced in the liver is converted to ketone bodies, causing an increase in blood ketone body concentration (17). ...
Article
Full-text available
In the 1950s, the production of processed fats and oils from coconut oil was popular in the United States. It became necessary to find uses for the medium-chain fatty acids (MCFAs) that were byproducts of the process, and a production method for medium-chain triglycerides (MCTs) was established. At the time of this development, its use as a non-fattening fat was being studied. In the early days MCFAs included fatty acids ranging from hexanoic acid (C6:0) to dodecanoic acid (C12:0), but today their compositions vary among manufacturers and there seems to be no clear definition. MCFAs are more polar than long-chain fatty acids (LCFAs) because of their shorter chain length, and their hydrolysis and absorption properties differ greatly. These differences in physical properties have led, since the 1960s, to the use of MCTs to improve various lipid absorption disorders and malnutrition. More than half a century has passed since MCTs were first used in the medical field. It has been reported that they not only have properties as an energy source, but also have various physiological effects, such as effects on fat and protein metabolism. The enhancement of fat oxidation through ingestion of MCTs has led to interest in the study of body fat reduction and improvement of endurance during exercise. Recently, MCTs have also been shown to promote protein anabolism and inhibit catabolism, and applied research has been conducted into the prevention of frailty in the elderly. In addition, a relatively large ingestion of MCTs can be partially converted into ketone bodies, which can be used as a component of “ketone diets” in the dietary treatment of patients with intractable epilepsy, or in the nutritional support of terminally ill cancer patients. The possibility of improving cognitive function in dementia patients and mild cognitive impairment is also being studied. Obesity due to over-nutrition and lack of exercise, and frailty due to under-nutrition and aging, are major health issues in today's society. MCTs have been studied in relation to these concerns. In this paper we will introduce the results of applied research into the use of MCTs by healthy subjects.
... When absorbed by enterocytes, LCFAs trigger chylomicron formation and are transported in the lymph, while MCFAs are primarily directed to the liver through the portal vein. In hepatocytes, MCFAs mostly avoid activation in the cytosol and enter mitochondria bypassing the carnitine transport system, which is limiting the LCFA transport to mitochondria when enough glucose is available [1]. Therefore, the main fate of MCFAs in hepatocytes is to be oxidized in the mitochondria, generating an excess of acetyl-CoA, while LCFAs are primarily esterified for TG storage, phospholipid synthesis, and excretion in very-low-density lipoprotein (VLDL) particles [2]. ...
... When MCFAs are rapidly oxidized in the mitochondria, the amount of acetyl-CoA, which exceeds the tricarboxylic acid (TCA) cycle capacity, can be redirected to various metabolic pathways, including ketogenesis in the mitochondria and de novo lipogenesis and cholesterol synthesis in the cytosol. The ketone bodies (KB) produced in the liver (including acetoacetate (AcAc) and β-hydroxybutyrate (BHB)) can be excreted into the blood and transported to other organs, including the brain, where the KB can be converted back to acetyl-CoA and enter the TCA cycle to produce ATP [1]. For LCFAs, the ketogenesis pathway only becomes significant under conditions such as starvation, high-fat-low-carbohydrate ketogenic diet (KD), or diabetes. ...
... When absorbed by enterocytes, LCFAs trigger chylomicron formation and are transported in lymph, while MCFAs are primarily directed to the liver through the portal vein. In hepatocytes, MCFAs mostly avoid activation in the cytosol and enter mitochondria bypassing the carnitine transport system, which is limiting the LCFA transport to mitochondria when enough glucose is available [1]. Therefore, the main fate of MCFAs in hepatocytes is to be oxidized in mitochondria, generating an excess of acetyl-CoA, while LCFAs are primarily esterified for TG storage, phospholipid synthesis, and excretion in very-low-density lipoprotein (VLDL) particles. ...
... When MCFAs are rapidly oxidized in the mitochondria, the amount of acetyl-CoA, which exceeds the tricarboxylic acid (TCA) cycle capacity, can be redirected to various metabolic pathways, including ketogenesis in the mitochondria, as well as de novo lipogenesis and cholesterol synthesis in the cytosol. The ketone bodies (KB) produced in the liver (including acetoacetate (AcAc) and β-hydroxybutyrate (BHB)), can be excreted into the blood and transported to other organs, including the brain, where the KB can be converted back to acetyl-CoA and enter the TCA cycle to produce ATP [1]. For LCFAs, the ketogenesis pathway only becomes significant under conditions such as starvation, high-fat-low-carbohydrate diet ketogenic diet (KD), or diabetes. ...
Preprint
Full-text available
Medium-chain triglycerides (MCT) have demonstrated a wide range of neuroprotective effects, although the mechanisms still remain poorly understood. Animal models are indispensable for such research. Metabolic effects of regular diet supplementation with fats must be considered. Male Wistar rats aged 2.5 months received (o/g) 3 g/kg/day of MCT oil, lard, or water (control) as a supplement to standard chow for 28 days. On the 17th day, the animals were tested in Y-maze. On the 28th day, blood was collected for biochemical testing (glucose, triglycerides (TG), total cholesterol (TC), HDL cholesterol). In a separate experiment, animals received 3 g/kg MCT, or lard, or water, and were then sacrificed 30 or 120 min after. Blood was collected for biochemical testing (glucose, lactate, pyruvate, acetoacetate, β-hydroxybutyrate (BHB), TC, TG, aspartate transaminase (AST), alanine transaminase (ALT)). In the Y-maze test, the MCT-fed rats demonstrated an increased frequency of spontaneous alterations compared to both the control and lard groups, indicating improved working memory. Chronic administration of neither fat affected the blood glucose, TG, TC, HDL cholesterol. Acutely, MCT supplementation elevated blood BHB, while lard did not. Lard increased blood TG, TC, and ALT, while MCT did not. Daily supplementation of standard feed with MCT led to mild intermittent ketosis and improved working memory in rats. Neither chronic nor acute MCT administration had any adverse effect on metabolic health markers. This animal model may be used to study the mechanisms of the cognitive-enhancing effects of MCT.
... The absorption of FA happens in the small intestine, mainly in the jejunum portion. Upon the enterocyte's entry, the acyl-CoA synthetase converts the absorbed FA with chain length >C10 to their coenzyme A derivatives and re-esterified them by the α-glycerolphosphate pathway to triglycerides (Bach and Babayan, 1982), and along with phospholipids, cholesterol, and apoproteins, they will be formed into chylomicrons, and very-lowdensity lipoproteins (VLDL; Bauchart, 1993). Lipoproteins (chylomicrons and VLDL) cannot be absorbed directly by intestinal cells due to their large size. ...
... On the other hand, the micelles' formation allows shorter chain FA = / <C10 to be absorbed into intestinal cells, with most being absorbed in the jejunum. These FA will leave the enterocyte mostly unmodified because they are not easily esterified or incorporated into lipoproteins and enter the venous portal system bound to albumin (Bach and Babayan, 1982). ...
Thesis
Full-text available
Controlling dry matter intake (DMI) is one strategy to meet the animal's requirements while reducing feed costs and increasing feed efficiency. Controlling intake through precision-feeding provides a more nutrient-dense diet, allowing an increase in energy and nutrient utilization efficiency while decreasing nutrient loss. The literature about precision feeding has provided information regarding optimal N intake and different dietary fiber proportions, but more information needs to be addressed. This is one of the first attempts to further our knowledge through the use of fat inclusion. In the present dissertation, a total of 4 in-vitro and in-vivo experiments were conducted. Simulated and applied precision feeding with different forage to concentrate (F:C) ratios and fat sources inclusion were used to determine the effect on Holstein and Jersey dairy heifer's digestibility and fermentation.
... Starting from the few available studies, we have summarized in Table 1 the possible alterations of the gut microbiota related to (i) the use of special dietary products, such as low-protein foods (LPs; Wang et al., 2019) and protein substitutes (Davila et al., 2013;Sawin et al., 2015;Lin et al., 2017;Yang and Liao, 2019), (ii) the use of specific nutrients, such as UCCS (Kishnani et al., 2014;Colonetti et al., 2019), medium chain triglycerides (MCTs; Bach and Babayan, 1982;Decuypere and Dierick, 2003;Das et al., 2010;Zentek et al., 2013), and long-chain polyunsaturated fatty acids (LC-PUFAs;Pinheiro de Oliveira et al., 2016;Pu et al., 2016;Costantini et al., 2017;Watson et al., 2018;Bassanini et al., 2019), or (iii) the exclusion/reduction of specific nutrients, as breast milk (Coppa et al., 2006;MacDonald et al., 2006;Hascoet et al., 2011;Videhult and West, 2016) and (iv) the utilization of special nutrition mode, as tube feeding (O'Keefe, 2010;Takeshita et al., 2011;Burlina et al., 2018). ...
... MCTs are widely used in the dietary treatment of some metabolic diseases, like in long-chain fatty acid (LCFA) oxidation disorders or in the deficiency of the carnitine system (Bach and Babayan, 1982), as well as in the ketogenic diet and recently also in GSDs (Das et al., 2010). ...
Article
Full-text available
Inborn errors of metabolism (IEMs) represent a complex system model, in need of a shift of approach exploring the main factors mediating the regulation of the system, internal or external and overcoming the traditional concept of biochemical and genetic defects. In this context, among the established factors influencing the metabolic flux, i.e., diet, lifestyle, antibiotics, xenobiotics, infectious agents, also the individual gut microbiota should be considered. A healthy gut microbiota contributes in maintaining human health by providing unique metabolic functions to the human host. Many patients with IEMs are on special diets, the main treatment for these diseases. Hence, IEMs represent a good model to evaluate how specific dietary patterns, in terms of macronutrients composition and quality of nutrients, can be related to a characteristic microbiota associated with a specific clinical phenotype (“enterophenotype”). In the present review, we aim at reporting the possible links existing between dysbiosis, a condition reported in IEMs patients, and a pro-inflammatory status, through an altered “gut-liver” cross-talk network and a major oxidative stress, with a repercussion on the health status of the patient, increasing the risk of non-communicable diseases (NCDs). On this basis, more attention should be paid to the nutritional status assessment and the clinical and biochemical signs of possible onset of comorbidities, with the goal of improving the long-term wellbeing in IEMs. A balanced intestinal ecosystem has been shown to positively contribute to patient health and its perturbation may influence the clinical spectrum of individuals with IEMs. For this, reaching eubiosis through the improvement of the quality of dietary products and mixtures, the use of pre-, pro- and postbiotics, could represent both a preventive and therapeutic strategy in these complex diseases.
... Dietary MCTs are partially hydrolyzed by lingual lipase in the stomach and then hydrolyzed rapidly and efficiently by pancreatic lipase within the intestinal lumen. A minor proportion of MCFAs bypass the liver and are distributed to peripheral tissues via general circulation [52][53][54]. Subsequently, MCFAs are directly absorbed through the gut via the portal vein to the liver, rather than through the thoracic duct lymph system, which is the conventional route for the absorption of triglycerides containing light-chain fatty acids [52]. Within the liver mitochondria, MCFAs are rapidly metabolized through β-oxidation and finally become ketone bodies, such as β-hydroxybutyrate (βHB), AcAc, and acetone. ...
Article
Full-text available
Recently, type 2 diabetes mellitus (T2DM) has been reported to be strongly associated with Alzheimer’s disease (AD). This is partly due to insulin resistance in the brain. Insulin signaling and the number of insulin receptors may decline in the brain of T2DM patients, resulting in impaired synaptic formation, neuronal plasticity, and mitochondrial metabolism. In AD patients, hypometabolism of glucose in the brain is observed before the onset of symptoms. Amyloid-β accumulation, a main pathology of AD, also relates to impaired insulin action and glucose metabolism, although ketone metabolism is not affected. Therefore, the shift from glucose metabolism to ketone metabolism may be a reasonable pathway for neuronal protection. To promote ketone metabolism, medium-chain triglyceride (MCT) oil and a ketogenic diet could be introduced as an alternative source of energy in the brain of AD patients.
... While MCTs and LCTs have equivalent energy, a meta-analysis in humans revealed that ingestion of MCTs induces less body weight gain than ingestion of LCTs (Mumme and Stonehouse, 2015). Known mechanisms underlying alleviation of obesity by MCT are changes in the intestinal flora (Zhou et al., 2017), increased expression of PPARg and adiponectin genes in adipose tissues (Takeuchi et al., 2006), increased b-oxidation in the liver (Bach and Babayan, 1982), activation of brown adipocytes (Zhang et al., 2015), and increased energy expenditure (St-Onge et al., 2003). We previously showed that a single ingestion of MCT oil stimulated GLP-1 secretion, but not GIP secretion (Murata et al., 2019). ...
Article
Full-text available
Long-chain triglycerides (LCTs) intake strongly stimulates GIP secretion from enteroendocrine K cells and induces obesity and insulin resistance partly due to GIP hypersecretion. In this study, we found that medium-chain triglycerides (MCTs) inhibit GIP secretion after single LCT ingestion and clarified the mechanism underlying MCT-induced inhibition of GIP secretion. MCTs reduced the CCK effect after single LCT ingestion in wild-type (WT) mice, and a CCK agonist completely reversed MCT-induced inhibition of GIP secretion. In vitro studies showed that medium-chain fatty acids (MCFAs) inhibit long-chain fatty acid (LCFA)-stimulated CCK secretion and increase in intracellular Ca²⁺ concentrations through inhibition of GPR120 signaling. Long-term administration of MCTs reduced obesity and insulin resistance in high-LCT diet-fed WT mice, but not in high-LCT diet-fed GIP-knockout mice. Thus, MCT-induced inhibition of GIP hypersecretion reduces obesity and insulin resistance under high-LCT diet feeding condition.
... Induction of the metabolic state ketosis, characterized by increased circulating levels of the ketone body β-hydroxybutyrate (BHB), is a hallmark of ketogenic diets (Volek et al., 2015). Supplements in the form of ketogenic medium-chain triglycerides (kMCT) (Bach and Babayan, 1982;Norgren et al., 2020b) and exogenous ketones (Poff et al., 2020) provide an opportunity to study ketosis in the absence of carbohydrate restriction. Improved cognitive performance in patients with Mild Cognitive Impairment (MCI) or AD has been reported after intake of kMCT in some (Reger et al., 2004;Henderson et al., 2009;Ota et al., 2019;Fortier et al., 2020), but not in other (Henderson et al., 2020), studies. ...
Article
Full-text available
Background: β-hydroxybutyrate (BHB) can upregulate brain-derived neurotrophic factor (BDNF) in mice, but little is known about the associations between BHB and BDNF in humans. The primary aim here was to investigate whether ketosis (i.e., raised BHB levels), induced by a ketogenic supplement, influences serum levels of mature BDNF (mBDNF) and its precursor proBDNF in healthy older adults. A secondary aim was to determine the intra-individual stability (repeatability) of those biomarkers, measured as intra-class correlation coefficients (ICC). Method: Three of the arms in a 6-arm randomized cross-over trial were used for the current sub-study. Fifteen healthy volunteers, 65–75 y, 53% women, were tested once a week. Test oils, mixed in coffee and cream, were ingested after a 12-h fast. Labeled by their level of ketosis, the arms provided: sunflower oil (lowK); coconut oil (midK); caprylic acid + coconut oil (highK). Repeated blood samples were collected for 4 h after ingestion. Serum BDNF levels were analyzed for changes from baseline to 1, 2 and 4 h to compare the arms. Individual associations between BHB and BDNF were analyzed cross-sectionally and for a delayed response (changes in BHB 0–2 h to changes in BDNF at 0–4 h). ICC estimates were calculated from baseline levels from the three study days. Results: proBDNF increased more in highK vs. lowK between 0 and 4 h (z-score: β = 0.25, 95% CI 0.07–0.44; p = 0.007). Individual change in BHB 0–2 h, predicted change in proBDNF 0–4 h, (β = 0.40, CI 0.12–0.67; p = 0.006). Change in mBDNF was lower in highK vs. lowK at 0–2 h (β = −0.88, CI −1.37 to −0.40; p < 0.001) and cumulatively 0–4 h (β = −1.01, CI −1.75 to −0.27; p = 0.01), but this could not be predicted by BHB levels. ICC was 0.96 (95% CI 0.92–0.99) for proBDNF, and 0.72 (CI 0.47–0.89) for mBDNF. Conclusions: The findings support a link between changes in peripheral BHB and proBDNF in healthy older adults. For mBDNF, changes differed between arms but independent to BHB levels. Replication is warranted due to the small sample. Excellent repeatability encourages future investigations on proBDNF as a predictor of brain health. Clinical Trial Registration: ClinicalTrials.gov , NCT03904433.
... MCFAs can be hydrolyzed rapidly and absorbed by the intestine in the form of FFAs, which then directly enter the portal venous system and are transported to the liver for β-oxidation and used as a fast energy source. 38,39 Therefore, when producing infant formulas, we should consider not only that the fatty acid composition should be close to that of human milk but also the similarity of the TAG structure to be an essential component to consider infant formulas in the future. ...
... In several studies, MCTs were found to improve memory and visual cognition [2,3] and slow down neurodegeneration [4,5]. Besides treating AD, MCTs have also been implicated in reducing the occurrence of body hyperlipidaemias, inflammation, obesity, and oxidative stress [6][7][8][9], amongst other metabolic diseases. ...
Article
Full-text available
Medium-chain triglycerides (MCTs) are an emerging choice to treat neurodegenerative disorders such as Alzheimer’s disease. They are triesters of glycerol and three medium-chain fatty acids, such as capric (C8) and caprylic (C10) acids. The availability of C8–C10 methyl esters (C8–C10 ME) from vegetable oil processes has presented an opportunity to use methyl esters as raw materials for the synthesis of MCTs. However, there are few reports on enzymes that can efficiently hydrolyse C8–C10 ME to industrial specifications. Here, we report the discovery and identification of a novel lipase from Lasiodiplodia theobromae fungus (LTL1), which hydrolyses C8–C10 ME efficiently. LTL1 can perform hydrolysis over pH ranges from 3.0 to 9.0 and maintain thermotolerance up to 70 °C. It has high selectivity for monoesters over triesters and displays higher activity over commercially available lipases for C8–C10 ME to achieve 96.17% hydrolysis within 31 h. Structural analysis by protein X-ray crystallography revealed LTL1’s well-conserved lipase core domain, together with a partially resolved N-terminal subdomain and an inserted loop, which may suggest its hydrolytic preference for monoesters. In conclusion, our results suggest that LTL1 provides a tractable route towards to production of C8–C10 fatty acids from methyl esters for the synthesis of MCTs.
... Complex mixtures of oils that contain modest levels of long-chain SFAs can be used in developing formulas with fatty acid profiles closer to that of human milk [57]. MCTs, predominantly containing caprylic acid (C8:0) and capric acid (C10:0), have been added to some preterm formulas to maximize fatty acid absorption in preterm infants [77]. ...
Article
Full-text available
Human milk is generally regarded as the best choice for infant feeding. Human milk fat (HMF) is one of the most complex natural lipids, with a unique fatty acid composition and distribution and complex lipid composition. Lipid intake in infants not only affects their energy intake but also affects their metabolic mode and overall development. Infant formula is the best substitute for human milk when breastfeeding is not possible. As the main energy source in infant formula, human milk fat substitutes (HMFSs) should have a composition similar to that of HMF in order to meet the nutritional needs of infant growth and development. At present, HMFS preparation mainly focuses on the simulation of fatty acid composition, the application of structured lipids and the addition of milk fat globule membrane (MFGM) supplements. This paper first reviews the composition and structure of HMF, and then the preparation development of structured lipids and MFGM supplements are summarized. Additionally, the evaluation and regulation of HMFSs in infant formula are also presented.
... Severe dietary fat restriction as mentioned above is effective, but oil intake in the form of medium-chain TGs may improve palatability without increasing chylomicron production. [16] When there is residual LPL activity, fibrates may add benefit beyond a fat-restricted diet. Up-regulation of LDL receptors by statins improves uptake of LDL, usually absent in severe hypertriglyceridaemia, but does not affect the clearance of chylomicrons and VLDL, which are the cause of severe hypertriglyceridaemia. ...
Article
Full-text available
Acute pancreatitis is an often-overlooked cause of acute abdominal pain in children and adolescents. Severe hypertriglyceridaemia is an important cause of recurrent acute pancreatitis. Monogenic causes of hypertriglyceridaemia, such as familial chylomicronaemia caused by lipoprotein lipase deficiency, are more frequently encountered in children and adolescents, but remain rare. Polygenic hypertriglyceridaemia is more common, but may require a precipitant before manifesting. With the global increase in obesity and type 2 diabetes, secondary causes of hypertriglyceridaemia in children and adolescents are increasing. We report two cases of severe hypertriglyceridaemia and pancreatitis in adolescent females. Hypertriglyceridaemia improved markedly with restriction of dietary fat. An inhibitor to lipoprotein lipase was found to be the cause in one patient, while in the other limited genetic investigation excluded chylomicronaemia owing to deficiency of lipoprotein lipase, its activators and processing proteins.
... The effect of these acids is both bactericidal (killing) and bacteriostatic (growth-inhibiting) depending on the concentration, synergism among them, and target bacterium (60,61). The acids most commonly used in diet supplementation for the control of microorganisms are formic acid, benzoic acid, citric acid, carboxylic acids (all SCFA) and their salts and as well as some MCFA including Caproic (C6:0), Caprylic (C8:0), Capric (C10:0) and Lauric acid (C12:0) (62,63). ...
Article
Full-text available
The use of antibiotic growth promoters (AGPs) has historically been the most important prophylactic strategy for the control of Necrotic Enteritis (NE) caused by some Clostridium perfringens toxin types in poultry. During the last five decades, AGPs have also been supplemented in feed to improve body weight gain and feed efficiency as well as to modulate the microbiome (consisting of microbes and their genes both beneficial and potentially harmful) and reduce enteric pathogens, among other benefits. New regulatory requirements and consumer preferences have led to strong interest in natural alternatives to the AGPs for the prevention and control of illnesses caused by enteric pathogens. This interest is not just focused on the direct removal or inhibition of the causative microorganisms but also the improvement of intestinal health and homeostasis using a range of feed additives. A group of promising feed additives is short- and medium-chain fatty acids (SCFA and MCFA, respectively) and their derivatives. The use of SCFA and MCFA, including butyric, caproic, caprylic, capric, and lauric acids, has shown strong effects against NE in broilers both at experimental and commercial levels. These fatty acids also benefit intestinal health integrity and homeostasis. Other effects have also been documented, including increases in intestinal angiogenesis and gene expression of tight junctions. Chemical modifications to improve stability and point of release in the intestine have been shown to improve the efficacy of SCFA and MCFA and their derivatives. The aim of this review is to give an overview of SCFA, MCFA and their derivatives, as an alternative to replace AGPs to control the incidence and severity of NE in poultry.
... Medium-chain fatty acids (MCFAs) are widely defined as straight-chain saturated fatty acids with a chain length ranging from 6 to 12 carbon atoms [7,8]. In a nutritional study, research on the alternative use of long-chain fatty acids started mainly on fatty acids with a chain length of 8 carbon atoms (octanoic acid, C8) and 10 carbon atoms (decanoic acid, C10) [7,9]. This was followed by research on biological regulatory functions different from those of long-chain fatty acids, one of which was research on the elimination of obesity [10,11]. ...
Article
Full-text available
The elimination of obesity is essential to maintaining good health. Medium-chain triglycerides (MCTs) inhibit fat accumulation. However, studies examining energy expenditure and fat oxidation with continuous ingestion of MCTs show little association with the elimination of obesity. In this study, we conducted a randomized, double-blind crossover clinical trial to investigate the effects of continuous ingestion of MCTs on postprandial energy expenditure and ingested long-chain triglycerides (LCTs) oxidation. A daily 2 g of MCTs were ingested for two weeks by sedentary participants with a body mass index (BMI) from 25 (kg/m2) to less than 30. Ingestion of a meal containing MCTs and isotopic carbon-13-labeled (13C) LCTs increased energy expenditure and consumption of diet-derived LCTs, as determined by postprandial 13C carbon dioxide excretion, compared to canola oil as the placebo control. These results indicate that continuous ingestion of MCTs could enhance postprandial degradation of diet-derived fat and energy expenditure in sedentary, overweight individuals.
... Additionally, MCT intake also increases the energy source by the rapid formation of ketone bodies, because an excess of acetyl-CoA is produced by metabolizing MCFAs in the liver (4,6). Thus, MCTs can be applied to people with high energy demands, such as athletes for enhancing their physical performance, the elderly who experience a decline in energy production due to aging, subjects undergoing surgery, and persons with stunted growth (7)(8)(9)(10). ...
Article
Full-text available
Background Dietary triglycerides are an important energy source; however, their excess intake causes metabolic diseases such as obesity and type 2 diabetes. Medium-chain triglycerides (MCTs) as triglyceride forms of medium-chain fatty acids (MCFAs) are applied to meet the energy demands of athletes, the elderly, and people with stunted growth, because MCFAs are efficiently converted into energy for immediate utilization by the organs and do not accumulate as fat. Although the intake of each MCT type (octanoate; C8:0, decanoate; C10:0, and dodecanoate; C12:0) exhibits beneficial metabolic effects, individual functional differences remain unclear. Methods MCTs or MCFAs were administrated to male GPR84-deficient mice with a C57BL/6J background and mouse enteroendocrine cell line STC-1, and the effects on glucose homeostasis and gut hormone GLP-1 secretion were evaluated. Results C10:0 intake improves glucose metabolism through the MCFA receptor GPR84-mediated GLP-1 secretion. Each MCT intake showed resistance to obesity and improved metabolic parameters compared with lard intake. Moreover, oral administration of MCTs enhanced glucose tolerance, especially C10:0 administration, which sufficiently increased plasma GLP-1 levels. Additionally, C10:0 stimulation promoted GLP-1 secretion via GPR84 in STC-1, enhanced glucose tolerance through GPR84-mediated GLP-1 secretion, and showed resistance to high-fat diet (HFD)-induced obesity in mice. Conclusions Dietary MCT (C10:0) intake efficiently may protect against obesity and improve insulin resistance via GLP-1 secretion.
Article
Chyle leak is a well-recognized iatrogenic thoracic duct injury but a rare and serious complication of head and neck surgery affecting 1-2.5% of head and neck surgery dissections. It is potentially a life-threatening condition and management may be problematic and prolonged. Here we presented a rare case report of right sided chyle leak with its surgical management and review of literature. A 56-year-old patient with a complain of non-healing ulcer in the right buccal vestibule in the last 1-2 months reported to the outpatient department (OPD). After complete preoperative profile and counseling patient's consent was taken and wide local excision of lesion was done with bite composite resection with right hemimandibulectomy and maxillary alveolectomy till pterygoid plates, with right side selective neck dissection, level I-III followed by reconstruction with right side pectoralis major myofascial flap. Then the patient was on 5 days octreotide therapy. Regular post-operative follow-up was taken and no leak was noted further. In case of a chyle leak early diagnosis and aggressive treatment is essential to avoid local and systemic complications that prolong hospitalization.
Article
Full-text available
Background: Home enteral nutrition (HEN) use continues to increase in children unable to meet nutritional needs through oral intake. Some patients do not tolerate standard polymeric formula (SPF), which may lead to malnutrition. Use of peptide-based diet (PBD) has demonstrated benefits in adults, however there remains a paucity of data in pediatric population. Methods: Retrospective review of medical records of children receiving HEN between October 2015 and October 2019 was conducted. Nutrition, tolerance, and healthcare utilization was tracked through May 2020. Children receiving PBD as initial formula or transitioned to PBD from SPF were included. Our objective was to assess gastrointestinal tolerance and impact on healthcare utilization in children receiving PBD. Results: During study period, 30 children (mean age, 9 ± 5.44 years; 20 of 30 [66.7%] male) utilized PBDs. Twenty-one patients started PBD directly with malnutrition as primary indication. Nine patients transitioned from SPF to PBD, most often due to intolerance of SPF (66%). After transition to PBD, no symptoms were reported in 6 of 9 (66.7%) patients, and symptoms of SPF intolerance resolved in 4 of 9 (44.5%) patients. Healthcare utilization declined significantly after transition to PBD, including mean numbers of emergency room visits (0.78 ± 1.09 to 0.11 ± 0.33; P = .025), provider visits (1.67 ± 1.32 to 0.56 ± 0.73; P = .007), and phone calls (1.22 ± 1.39 to 0.33 ± 0.50; P = .026). Conclusions: PBD is well tolerated and can result in significant reduction in healthcare utilization in children intolerant to SPF.
Article
Full-text available
Background: Ketone bodies are a highly relevant topic in nutrition and medicine. The influence of medium-chain triglycerides (MCT) on ketogenesis is well known and has been successfully used in ketogenic diets for many years. Nevertheless, the effects of MCTs and coconut oil on the production of ketone bodies have only partially been investigated. Furthermore, the increased mobilisation of free fatty acids and release of catabolic hormones by caffeine suggest an influence of caffeine on ketogenesis. Methods: In a controlled, double-blind intervention study, seven young healthy subjects received 10 mL of tricaprylin (C8), tricaprin (C10), C8/C10 (50% C8, 50% C10), or coconut oil with or without 150 mg of caffeine, in 250 mL of decaffeinated coffee, over ten interventions. At baseline and after every 40 minutes, for 4 h, ßHB and glucose in capillary blood as well as caffeine in saliva were measured. Furthermore, questionnaires were used to survey sensory properties, side effects, and awareness of hunger and satiety. Results: The interventions with caffeine caused an increase in ßHB levels-in particular, the interventions with C8 highly impacted ketogenesis. The effect decreased with increased chain lengths. All interventions showed a continuous increase in hunger and diminishing satiety. Mild side effects (total = 12) occurred during the interventions. Conclusions: The present study demonstrated an influence of caffeine and MCT on ketogenesis. The addition of caffeine showed an additive effect on the ketogenic potential of MCT and coconut oil. C8 showed the highest ketogenicity.
Article
This study evaluated the effects of increasing levels of the greasy babassu byproduct (GBB) in the diet of lambs on the fatty acid (FA) profile of abomasal digesta content, meat quality traits, and meat FA profile. Twenty-eight crossbred Dorper × Santa Inês growing lambs (20.6 ± 4.1 kg of initial body weight and 145 ± 12 days old) were fed one of four experimental diets as dry matter (DM): 1) basal diet (i.e. without the GBB, CON), 2) basal diet with 50 g/kg GBB (50GBB), 3) basal diet with 100 g/kg GBB (100GBB) and, 4) basal diet with 150 g/kg GBB (150 GBB). The animals (experimental unit) were distributed in a randomized design, 4 treatments and 7 replications of each treatment. The GBB addition increased the DM intake linearly but decreased nutrient utilization, resulting in no changes in metabolizable energy intake and consequently, growth performance. Meat chemical composition, physical traits, and sensory evaluation were not affected by diet. The GBB diet increased the abomasal contents of 10:0, 12:0 and 14:0 and tended to decrease 18:0, appointing for the negative interference on the rumen biohydrogenation (BH) of 18:2 n–6 and 18:3 n–3. The changes in the abomasal FA content did not affect the meat FA profile, except for a slight increment of 12:0, with increasing dietary GBB. Thus GBB, up to 150 g/kg of dietary DM, can be used as an alternative energy source for lambs, promoting slight changes in FA abomasal contents and rumen BH, without modifying growth performance, meat quality, and meat FA composition.
Article
Short bowel syndrome (SBS) of infancy is a cause of prolonged morbidity with intolerance to enteral feeding, specialized nutritional needs, and partial/total dependence on parenteral nutrition. These infants can benefit from individualized nutritional strategies to support and enhance the process of intestinal adaptation. Early introduction of enteral feeds during the period of intestinal adaptation is crucial, even though the enteral feedings may need to be supplemented with an effective, safe, and nutritionally adequate parenteral nutritional regimen. Newer generation intravenous lipid emulsions can be effective in preventing and treating intestinal failure-associated liver disease. Prevention of infection(s), pharmaceutical interventions to enhance bowel motility and prevent/mitigate bacteria overgrowth, and specialized multidisciplinary care to minimize the injury to other organs such as the liver, kidneys, and the brain can assist in nutritional rehabilitation and lower the morbidity in SBS.
Article
Full-text available
Iatrogenic chyle leak is commonly seen when dissection happens very low in neck. Management of chyle leak is conservative with compression dressing, fat restricted diet, somatostatin analogues. Surgery is required in extreme cases with failure of conservative treatment. This is a retrospective observational study carried out from a prospectively maintained database. A total of 6482 head and neck surgeries with neck dissections were carried out between January 2015 till July 2020 at our tertiary cancer center. Out of which there were 52 cases of chyle leak reported post neck dissection. All details regarding age, sex, primary tumor location, surgery performed, level of nodal dissection performed, details related to chyle leak from beginning day and its progression and management offered. The median age in the study group was 42 years (24–70 years). Chyle leak was most commonly seen on left side (88.5%). Low output leaks(n = 43) resolved within a median period of 9 days (5–13 days) period of conservative management. High output leak (n = 9) had leak resolution within a median period of 12 days (7–19 days). Patients who had received preoperative radiotherapy and who had extra nodal extension in lymph nodes had significantly higher incidence of high output leaks. Chyle leak is a rare but serious complication in head and neck surgery. Timely identification and management is crucial. Conservative management is mainstay. Surgical management is instituted in cases of failure of conservative management.
Article
Understanding fat structure and mechanical properties is crucial for the processing and mouthfeel of fat-rich foods. In this study, we systematically explored the impact of changes in the composition of fully hydrogenated palm kernel oil (FHPKO) on its crystallization behavior, nano/microstructure, and mechanical properties by blending with 1, 2, 3, 4, 5, 10, and 20% triolein (OOO). Changes in the triglycerides (TAGs) composition of FHPKO affected its crystal habit and therefore its functionality. The lower melting unsaturated OOO remarkably increased the onset of crystallization temperature and time of FHPKO, particularly with the addition of 10% and 20% OOO. The addition of OOO also slowed down the nucleation and crystal growth rate owing to the dilution of the high-melting point TAGs. X-ray diffraction analysis showed a similar lamellar longitudinal size for all fat blends. However, the crystal domain size increased with the addition of OOO, which was caused by an increase in the amount of liquid oil between the lamellae. In addition, large crystal particles were observed with an increase in OOO content, leading to a weak interaction between the clusters with a low fractal dimension, thus reducing the strength of the mechanical properties of the fat crystal network.
Chapter
Adequate nutrition is vital for even the most basic biochemical reactions to occur. However, there are conditions and diseases in which people are not able to take in sufficient nutrition orally, and nutrition must be provided via other methods to meet caloric requirements. Enteral nutrition is nutrition provided directly to the gastrointestinal tract via a tube, catheter, or stoma distal to the oral cavity, while parenteral nutrition is nutrition administered directly into the venous system. Enteral nutrition is always preferred when technically feasible in a person with a functional gastrointestinal tract. In this chapter, we will discuss the indications for enteral nutrition, types of enteral access devices, enteral feeding formulations, special considerations when initiating enteral nutrition in certain populations, and complications of enteral nutrition.
Article
Four different model infant formulae were compared under simulated conditions of the infant gastrointestinal tract using an in vitro dynamic digestion protocol. These formulae were based on whey protein isolate, whey protein isolate + lactoferrin, long chain triacylglycerols or long + medium chain triacylglycerols. In each of the four cases, the influence of protein and lipid composition on their subsequent structural disintegration, proteolysis and lipolysis during digestion was investigated. Structural characterization of the four types of infant formulae was done before and during simulated digestion using confocal microscopy and laser light scattering methods. Proteolysis was followed using molecular weight distribution methodology, primary amine quantification, amino acid bioaccessibility and peptide analyses. Lipolysis was determined by gas chromatography. During gastric digestion, the structure of infant formulae based on lactoferrin was barely affected by the physicochemical conditions in the gastric chamber and all the protein fractions were found to be resistant to gastric proteolysis, except for α-lactalbumin. The degree of lipolysis within the gastric and intestinal phase was influenced by the lipid composition, noting that those formulae containing medium chain triacylglycerols exhibited a higher extent of lipolysis. These results are relevant for the development of formulae enriched with functional ingredients that may provide bioactive peptides and faster energy delivery to the newborn baby.
Article
Full-text available
Introduction Functional gastrointestinal disorders (FGIDs) are common in children and incur high direct and indirect social costs. Partially hydrolyzed guar gum (PHGG) is a natural and water-soluble dietary fiber that is derived from guar gum. It has been proposed as complementary therapy in pediatric FGIDs, especially in chronic functional constipation and irritable bowel syndrome. Areas covered By focusing on four clinical cases, this article illustrates the use of PHGG fiber as sole supplement ingredient or as a formula component in orally- and tube-fed children suffering from malnutrition due to FGIDs, with or without special medical conditions such as neurological disability. The formula used was a whey peptide-based nutritionally complete formula containing PHGG as a source of soluble dietary fiber. It was offered under medical supervision and after full consideration of all feeding options. Expert opinion Implementing appropriate feeding behaviors, adapted to age and potential comorbidities, is an essential requisite for therapeutic management of FGIDs. The use of a PHGG supplement or a nutritionally complete formula containing PHGG as a source of soluble dietary fiber can be helpful to manage pediatric FGIDs.
Article
Full-text available
Many studies show that glucose metabolism in epileptic brain areas can be impaired. Energy is crucial to maintain normal brain function, including ion and neurotransmitter balances. Energy deficits can lead to disruption of ion gradients, which can trigger neuronal depolarization and generation of seizures. Thus, perturbed metabolic processing of glucose in epileptogenic brain areas indicates a specific nutritional need for people and animals with epilepsy, as they are likely to benefit from auxiliary brain fuels other than glucose. Ketogenic diets provide the ketone bodies acetoacetate and β‐hydroxybutyrate, which can be used as auxiliary fuel by the brain. In approximately 50% children and adults with certain types of epilepsy, who can tolerate and maintain these dietary regimens, seizure frequency can be effectively reduced. More recent data demonstrate that addition of medium chain triglycerides (MCTs), which provide the medium chain fatty acids octanoic and decanoic acid, as well as ketone bodies as auxiliary brain energy, can be beneficial in rodent seizure models, and dogs and humans with epilepsy. Here, this evidence is reviewed, including tolerance in 65% of humans, efficacy studies in dogs, possible anticonvulsant mechanisms of actions of MCTs, and specifically decanoic acid as well as metabolic and antioxidant mechanisms. In conclusion, MCTs are a promising adjunct to standard pharmacological treatment for both humans and dogs with epilepsy, as they lack central nervous system side effects found with current antiepileptic drugs. There is now a need for larger clinical trials in children, adults, and dogs to find the ideal composition and doses of MCTs and the types of epilepsy that respond best.
Article
In last decades, a phenomenon named nutrition transition has been observed in many countries around the world. It has been characterised by increased consumption of fat-rich diets, predisposing to cardiometabolic diseases and high prevalence of the obesity. In the dietary recommendations cited to prevent metabolic diseases, there is a consensus to decrease intake of saturated fatty acids (SFA) to less than 10% of total energy intake, as recommended by the Food Safety Authorities. However, fatty acids of different chain lengths may exhibit different cardiometabolic effects. Thus, our major aim was to review the cardiometabolic effects of different classes of SFA according to carbon chain length, i.e. short-, medium- and long-chains. The review emphasises that not all SFA may have harmful cardiometabolic effects since short- and medium-chain SFA can provide beneficial health effects and participate to the prevention of metabolic disorders.
Article
We previously reported that consuming a ketogenic diet containing medium-chain triacylglycerols (MCTs) might be a valuable dietary strategy for endurance athletes. However, the long-term safety of the diet has not been established, and there is a concern that a higher intake of MCTs increases the liver triacylglycerol content. In this study, we found that consuming an MCT-containing ketogenic diet for 24 weeks decreased, rather than increased, the liver triacylglycerol concentration and did not aggravate safety-related blood biomarkers in male Wistar rats. Our results may therefore suggest that the long-term intake of a ketogenic diet containing MCTs may have no deleterious effects on physiological functions.
Article
Full-text available
Background Dysfunction of the gastrointestinal tract (GIT) is one of the most common non-motor symptom of Parkinson’s Disease (PD). Pathological processes causing PD were suggested to initiate in the enteric nervous system (ENS) and proceed to the central nervous system (CNS). There are studies showing that low-carbohydrate ketogenic diets can improve motor symptoms of PD. Caprylic acid (C8) is the principal fatty acid component of the medium-chain triglycerides in the ketogenic diets. In this study, we aimed to evaluate the effects of caprylic acid, in neurotoxin exposed zebrafish focusing on the relationship between intestinal and brain oxidative stress and inflammation. Methods Adult zebrafish were exposed to rotenone (5 μg/L) (R group) and caprylic acid (20 and 60 mg/mL) (L + HDCA and R + HDCA groups) for 30 days. At the end of 30 days locomotor activities were determined. Levels of lipid peroxidation (LPO), nitric oxide, glutathione and superoxide dismutase and glutathione S-transferase activities were determined by spectrophotometric methods and gene expressions of tnf⍺, il1, il6, il21, ifnɣ and bdnf were evaluated by RT-PCR in the brain and intestinal tissues of zebrafish. Results Caprylic acid ameliorated LPO, NO, SOD and the expressions of tnf⍺, il1, il6, il21, ifnɣ and bdnf in brain and intestines. Locomotor activities were only ameliorated in high dose R + HDCA group. Conclusions Caprylic acid ameliorated the neurotoxin-induced oxidative stress and inflammation both in the brain and intestines and enhanced locomotor activity in zebrafish. Graphical abstract
Chapter
Enteral nutrition is a widely used technique for nutritional support which delivers a homogeneous, liquid nutrition admixture into the digestive tract by tube, into the stomach, duodenum, or the proximal jejunum. It is used to preserve nutritional status, support normal growth, and treat malnutrition when oral feeding is inadequate or not possible. The physiological bases underlying its implementation, as well as indications for programs of enteral nutrition in pediatric age, its composition according to the indication, and its complications are detailed in this chapter.
Chapter
Most of the dietary lipids found in food are in the form of triacylglycerols (TAGs), cholesterol, and phospholipids, with TAGs often representing more than 95% of the total lipids. In natural foods (e.g., meat, fish, dairy, and nuts), they are often a part of structures in which the lipid particles are coated with a solubilizing layer or multilayer of membrane phospholipids and proteins. In processed foods, lipids are extracted from animal or plant materials and are then incorporated within the food matrix in the form of emulsions (e.g., yoghurt, cheese, spreads, salad dressings, ice creams, confectionery products, and chocolate). Breaking down the surrounding structures and releasing the lipid droplets from the food matrix affect the rate of lipid digestibility and the bioavailability of fatty acids at the point of utilization in the human body. The consumption of long-chain n-3 polyunsaturated fatty acids (LCn-3PUFAs) has been related to important health benefits, and understanding the different factors affecting their bioavailability from foods becomes critical. The structures of the lipids and matrices also play an important role in the rates of digestion, absorption, and bioavailability of LCn-3PUFA-rich lipids. Limited studies on the relationship between structure and lipid digestibility in natural and fabricated LCn-3PUFA-enriched foods have been carried out. This chapter focuses on the impact of food structures and matrices on lipid digestion and absorption, with a particular focus on LCn-3PUFA-containing model emulsion systems and food products.
Chapter
This chapter provides an overview of the major types of fatty acids, including polyunsaturated, monounsaturated, and saturated fatty acids. It reviews the differences in structural and biochemical properties of these fatty acids to provide a foundation for understanding the metabolic effects of each. We describe plant-based oils that are composed primarily of polyunsaturated fatty acids (soybean, corn, and walnut oil), monounsaturated fatty acids (canola and rapeseed, sunflower and safflower, olive, and peanut oil), saturated fatty acids (palm and palm kernel and coconut oil), and trans-fatty acids (partially hydrogenated vegetable oil). Finally, we will examine and compare the effects of these different oils on metabolic and cardiovascular outcomes based on a comprehensive review of the current literature.
Article
Full-text available
Rotenone is used to generate Parkinson's Disease (PD) like symptoms in experimental animals. Octanoic acid (C8), is the principal fatty acid of medium-chain triglycerides in ketogenic diets. Beneficial effects of ketogenic diets were shown in PD. We applied proteomic methods to reveal the effects of octanoic acid in rotenone toxicity in zebrafish to gain information on the use of ketogenic diets in PD. Zebrafish were exposed to 5μg/ml rotenone and octanoic acid (20 mg/ ml and 60 mg/ml) for 30 days. LC-MS/MS analysis was performed. Raw files were analyzed by Proteome Discoverer 2.4 software, peptide lists were searched against Danio rerio proteins. STRING database was used for protein annotations or interactions. 2317 unique proteins were quantified, 302 proteins were differently expressed. Proteins involved in cell organization, biogenesis, transport, response to stimulus were most frequently expressed. Our study is first to report that the alterations in the expressions of proteins related with energy and redox system, stress response and cytoskeleton proteins caused by rotenone exposure were normalized by octanoic acid treatment in zebrafish.
Article
Medium chain triglycerides (MCT) are esters of fatty acids with 6 to 12 carbon atom chains. Naturally, they occur in various sources; their composition and bioactivity are source and extraction process-linked. The molecular size of MCT oil permits unique metabolic pathways and energy production rates, making MCT oil a high-value functional food. This review details the common sources of MCT oil, presenting critical information on the various approaches for MCT oil extraction or synthesis. Apart from conventional techniques, non-thermal processing methods that show promising prospects are analyzed. The biological effects of MCT oil are summarized, and the range of need-driven modification approaches are elaborated. A section is devoted to highlighting the recent trends in the application of MCT oil for food, nutraceuticals, and allied applications. While much is debated about the role of MCT oil in human health and wellness, there is limited information on daily requirements, impact on specific population groups, and effects of long-term consumption. Nonetheless, several studies have been conducted and continue to identify the most effective methods for MCT oil extraction, processing, handling, and storage. A knowledge gap exists and future research must focus on technology packages for scalability and sustainability.
Article
Full-text available
A feeding trial of eight weeks was conducted to examine the influence of food supplementation with lauric acid (LA) on Acanthopagrus schlegelii (juvenile black sea bream). A 24 percent fish meal baseline diet was created, while the other two diets were generated with dietary supplementation of graded points of LA at 0.1 percent and 0.8 percent, respectively. Each diet was given a triplicate tank with 20 fish weighing 6.22 ± 0.19 g. In comparison with the control group, the weight gain rate, growth rate, as well as feed efficiency of fish fed of 0.1 percent diet of LA were considerably (P < 0.05) greater. The total body and dorsal muscle proximate compositions did not change significantly between groups (P > 0.05). Triglyceride (TG) content was considerably (P < 0.05) greater in the LA-supplemented meals eating group in comparison with the control group. In the group eating LA-supplemented meals, the height of villus and the number of goblet cells/villus were considerably (P < 0.05) larger. The microbial makeup of the gut was also studied. The differences in phyla, class, and family level were not statistically significant (P > 0.05). Firmicutes in the phylum, Betaproteobacteri, Gammaproteobacteria, and Clostridia in the class, and Clostridiaceae in the family were all substantially increased with higher levels of LA supplementation (P < 0.05). According to the findings of this study, an LA-supplemented diet improves fish development, antioxidative capability, gut microbiota and intestinal health.
Article
Full-text available
Medium chain fatty acids (MCFAs) has unique transport system and is rapidly metabolized in the body. It mainly occurs in coconut oil, palm kernel oil and milk products. Dietary supplementation with MCFAs can improve metabolic features as well as cognition in humans. Some of the effects of MCFAs may be through direct receptor-mediated intracellular pathways, but MCFAs are also metabolic regulators that can alter circulating levels of hormones and metabolites, and hence may indirectly mediate body metabolism. Here we describe how dietary medium chain fatty acid, previously found to improve immune response and insulin secretion via G-protein coupled receptors, can increase apoptosis in cancer cells through the activation of the EGFR/ERK/AP1 trans-duction pathway. MCFA-enriched diets could therefore be used to manage metabolic diseases through the modification of gut microbiota, activation of GPR 40 and GPR 84.
Article
Full-text available
Medium-chain fatty acids (mc-FAs) are currently applied in the treatment of long-chain fatty acid oxidation disorders (lc-FAOD) characterized by impaired β-oxidation. Here, we performed lipidomic and proteomic analysis in fibroblasts from patients with very long-chain acyl-CoA dehydrogenase (VLCADD) and long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHADD) deficiencies after incubation with heptanoate (C7) and octanoate (C8). Defects of β-oxidation induced striking proteomic alterations, whereas the effect of treatment with mc-FAs was minor. However, mc-FAs induced a remodeling of complex lipids. Especially C7 appeared to act protectively by restoring sphingolipid biosynthesis flux and improving the observed dysregulation of protein homeostasis in LCHADD under control conditions.
Article
The rising obesity rate underpins the increasing incidences of many chronic diseases, which are associated with substantial mortality worldwide. The changes of specific fatty acids in lipid profiles and its association with anti-obesity are not entirely clear. The purpose of this study was to determine the fatty acid metabolism of a novel structured lipid prepared from soybean oil and coconut oil in C57BL/6J mice. The lipid digestion rate of SLs was higher than physical blend (SOCO) and soybean oil on in vitro digestion model. The conversion of essential FAs (18:2n-6 and 18:3n-3), oxidation of saturated FAs in the liver, and the digestion and absorption of saturated FAs in the intestine increased with increasing SLs content. In addition, the mRNA expression of hepatic β-oxidation genes (PPARα and ACO), was higher in the SLs diet groups than in the HFD group, whereas the mRNA expression of lipogenesis genes (SREBP-1c, ACC-1, SCD-1 and FAS) showed the opposite trend. It is concluded that prepared structured lipids can use as one kind of functional oils to resist obesity.
Article
Full-text available
Medium-chain triacylglycerides (MCTs) are dietary supplements that can induce ketosis without the need for a traditional ketogenic diet or prolonged fasting. They have the potential to marginally delay the progression of neurodegenerative diseases, such as Alzheimer's disease. However, there have been inconsistencies in reports of the MCT dose–response relationship, which may be due to differences in MCT composition, participant characteristics, and other factors that can influence ketone generation. To resolve these discrepancies, we reviewed studies that investigated the ketogenic effect of MCTs in healthy adults. Aside from the treatment dose, other factors that can influence the ketogenic response, such as accompanying meals, fasting duration, and caffeine intake, were assessed. Based on the available literature, four practical recommendations are made to optimize the ketogenic effect of MCTs and reduce unwanted side effects (primarily gastrointestinal discomfort and diarrhea). First, the starting dose should be either 5 g of octanoic acid [caprylic acid (C8); a component of MCTs] or 5 g of a combination of C8 and decanoic or capric acid (C10; another component of MCTs), and the dose should be progressively increased to 15–20 g of C8. Second, MCTs should be consumed after an overnight fast, without an accompanying meal if tolerable, or with a low-carbohydrate meal. Third, the addition of caffeine may slightly increase the ketogenic response. Fourth, emulsifying the MCTs might increase their ketogenic effect and alleviate side effects.
Article
Full-text available
This trial was conducted to assess the impact of medium-chain α-monoglycerides, glyc-erol monolaurate (GML) supplementation on the growth performance, apparent ileal digestibility coefficient (AID%) of amino acids, intestinal histomorphology, and blood biochemical parameters of broiler chickens. Three-day-old chicks (76.82 g ± 0.40, n = 200) were haphazardly allocated to four experimental groups with five replicates for each (10 chicks/replicate). The treatments consisted of basal diets supplemented with four glycerol monolaurate levels; 0, 1, 3, or 5 g kg −1 (GML0, GML1, GML3, and GML5, respectively). Growth performance was determined at three periods (starter, grower, and finisher). Dietary GML had no significant effect on the growth performance parameters (body weight, weight gain, and feed conversion ratio) through all the experimental periods. GML1 diet increased the AID% of leucine and decreased the AID% of arginine. GML1 diet increased the duodenal and jejunal villous height and the jejunal muscle thickness. GML3 and GML5 diets increased the goblet cell count in the duodenum. GML supplementation increased the serum level of high density lipoprotein (HDL)-cholesterol. GML5 diet increased the serum levels of IgM and in-terleukin 10 compared to the control group.
Article
Full-text available
The binding of hexanoic, octanoic, and decanoic acids to defatted human plasma albumin was measured by equilibrium dialysis at 37° in a calcium-free Krebs-Ringer phosphate buffer, pH 7.4. The results were analyzed in terms of multiple stepwise equilibria. For each of the albumin binding sites, the magnitude of the equilibrium constants increased as the chain length of the acid increased: decanoate > octanoate > hexanoate. The first six equilibrium constants ranged from 1.5 x 10⁴ to 4.7 x 10 for hexanoate, from 3.4 x 10⁴ to 1.2 x 10³ for octanoate, and from 10⁵ to 3.4 x 10³ for decanoate. In each case, the equilibrium constants occurred in a generally descending order, suggesting that major cooperative binding effects do not occur over the physiologically important range of fatty acid-albumin molar ratios. The equilibrium constants calculated for each of the three acids could not be grouped in a common way in terms of classes of binding sites, indicating that a single, uniform class-site binding model cannot be applied to these medium chain fatty acids. Octanoate binding was relatively insensitive to pH changes over the range of 6.0 to 8.2. Decanoate binding also was similar at pH 6.5 and 7.4. A decrease in octanoate binding occurred when the albumin was acetylated or when the medium contained 6 m urea. Octanoate binding also was decreased when either palmitate or oleate was added to albumin, suggesting that medium chain fatty acid transport may be influenced by changes in the plasma long chain free fatty acid concentration.
Article
Full-text available
The mechanism whereby overfeeding with diet containing medium chain triglyceride (MCT) results in diminished body weight and fat was studied. Fifteen male Sprague-Dawley rats were fitted under anesthesia with gastrostomy tubes and divided into two groups. One group was fed MCT diet, the other an isocaloric diet containing long chain triglyceride (LCT) in excess (150%) of spontaneous calorie intake. Both diets, fed for 6 wk, derived 50% of calories from fat. Basal and norepinephrine (25 micrograms/100 g) stimulated 02 consumption and CO2 production, as well as metabolic rate were measured. After the rats were killed, total dissectible fat and fat cell size and number were determined. MCT rats gained 15% less weight than LCT controls (p less than 0.001). Total dissectible fat was significantly lower (p less than 0.001) in MCT group, as was mean adipocyte size (p less than 0.001). Resting and maximal norepinephrine-stimulated 02 consumptions were 39.7 and 22.1% higher in MCT than in LCT group, respectively. Resting and norepinephrine-stimulated metabolic rates were 38.8 and 22.2% higher in MCT than LCT fed rats, respectively. Overfeeding MCT diet results in decreased body fat related to increased metabolic rate and thermogenesis.
Article
Normally, rats and mice eat chow-type rations. When fed such a ration, body fat usually ranges between 11 and 18%. If a semi-purified diet high in fat is fed instead of the chow-type ration, some strains of rats and mice respond by accumulating abnormal amounts of weight and fat. Their bodies now contain as much as 40% fat and fat depots are enlarged. Rats which respond to a high fat diet with excessive weight and fat gain consume more kilocalories in the same time interval and are more efficient in energy utilization than rats of the same strain which consume a grain diet. For these rats, if medium-chain triglycerides are substituted for the long-chain triglycerides in the high fat diet, there is a depression in food intake, accretion of body weight and fat as well as energy utilization. Blood makes up 3.5 to 5.1% of the fat organ weight. The lower value represents the quantity present in adipose tissue of obese rats while the higher value is for “normal-weight” rats. The triglyceride content of perirenal and epididymal fat depots is around 90%. On the other hand, the triglyceride content of inguinal fat tissue ranges from 56 to 80% and is affected by strain, age and diet. If diets are high in fat, the proportional distribution of fatty acids in the adipose tissue reflects the proportional distribution in dietary fat, except when medium-chain triglycerides are fed.
Article
In hospitalized infants receiving either prolonged total parenteral nutrition without fat or a formula of medium-chain triglyceride, the fatty acid composition of platelet, red blood cell, and plasma lipids was determined. The results showed that the changes in the fatty acid composition occurred not only in plasma but also in platelets and red blood cells, and the decrease in linoleic and arachidonic acid and the concurrent increase in 5,8,11-eicosatrienoic acid were confirmed to be dramatic evidence of essential fatty acid deficiency. There was no effect of essential fatty acid deficiency upon the phospholipid distribution in red blood cells or plasma.
Article
Adult male BHE rats were fed diets containing 15% of either corn oil (CO) or medium chain triglycerides (MCT) as the dietary source of fat. Further, rats were allowed to remain sedentary or were forced to exercise by swimming for 1 hour daily, for 3 weeks, followed by swimming for 2 hours daily for 3 weeks. The exercise for 3 weeks caused significant reductions in average body weight gains. After 6 weeks of exercise the lipid content of the adipose cells was reduced by about 50%. Fat cell numbers were not changed by either fat source or exercise, but fat cell size was significantly reduced after swimming daily for 6 weeks.
Article
The short chain fatty acid sodium octanoate was infused into rabbits as an 0.2 M solution over 4 hours, resulting in blood and brain levels of 200 to 700 mumoles per liter. During the infusion, animals exhibited marked hyperventilation, resulting in a mild respiratory alkalosis. Octanoate infusion also resulted in significant hyperammonemia and lactic acidemia. Saline-treated control animals demonstrated no clinical or chemical abnormalities. Several short chain fatty acids, including octanoate, are increased in the plasma of patients with hepatic encephalopathies and Reye syndrome. The present study suggests that short chain fatty acids may be endogenous toxins in these clinical disorders. In particular, the central hyperventilation in these conditions may be due to the neurotoxic effect of short chain fatty acids.
Article
The increase in perfusion rate of medium chain triglycerides in the dog causes a rise in triglyceridernia, lipacidemia and ketonemia. Whether perfusion is slow or rapid, there is decrease in glycemia and increase in insulinemia. When the triglycerides load is less than 0.0200 g x kg−1 x min−1 evolution of lactatemia and pyruvicemia occurs in two stages (a decrease followed by a rise). Beyond this dose, only the ascending stage of plasma levels of the two metabolites is observed. Increase in glucose consumption by the organism might explain the hypoglycemia and the decrease in plasma lactate and pyruvate observed from the beginning of the perfusion. The later increase of the two metabolites, although hypoglycemia persists, might be due to inhibition of gluconeogenesis caused by the rise in insulinemia and particularly by reduction in the redox state.
Article
Medium-chain odd carbon fats have been reported to be ketogenic as have medium-chain triglycerides (MCT). Such an odd carbon fat, tripelargonin, was compared to MCT for its effect on ketogenic and glucogenic intermediates when fed as a part of a complete diet to meal-eating rats. Isonitrogenous diets containing, as 68% of the calories, soy oil (SO), MCT, tripelargonin (C9TG) were fed 2 hours twice a day. After 4 weeks, the C9TG rats during meals had blood and liver beta-hydroxybutyrate levels approximately 300 and 125%, respectively, of the fasting levels and similar to the prandial SO-fed levels. These levels were significantly less than the 1,000 and 500% elevations observed in the MCT-fed rats. Prandial blood glucose and liver glycogen levels were similar in the C9TG and SO-fed rats; whereas, these intermediates appeared to remain at or drop below the fasting levels in the MCT-fed animals. Levels of plasma non-esterified fatty acids and liver glucose-6-phosphate in the MCT and C9TG were similar and different from the SO-fed values. The results point to the uniqueness of C9TG when compared to even-numbered triglycerides under these dietary conditions.
Article
To test whether the property of medium-chain fatty acids (which have 6-12 carbon atoms) being incorporated only in small amounts into the various tissues of a living organism could be exploited to treat obesity, genetically obese Zucker rats and their lean littermates were fed a diet containing 20% medium-chain triacylglycerols (MCT) or long-chain triacylglycerols (LCT) for 10 weeks. MCT, as compared with LCT, had the following effects: 1) MCT did not diminish weight gain in either the nonobese or the obese rats; 2) they increased ketogenesis more in the former than in the latter; 3) they increased the concentration of triacylglycerols in the liver of the obese rats but not of the lean ones; 4) they decreased the concentration of cholesterol in the liver of the lean but not of the obese rats, and 5) they did not particularly affect the concentration of proteins, glucose and insulin in the blood. We therefore conclude that the influence of the genotype is much more important in the establishment of the biochemical characteristics of rats than is the nature of the fatty acids ingested. Replacing LCT in the diet with MCT did not correct any of the major metabolic disorders in obese rats and therefore cannot unaided constitute a solution to the problem of genetic obesity.
Article
Weight gain was measured in rats fed test diets with two types of fat: corn oil and medium-chain triglycerides (MCT). These diets were selected because fatty acids from corn oil enter the circulation as chylomicrons through the lacteals. Fatty acids from medium-chain triglycerides reach the liver directly through the portal circulation. Weight gain was normal when the diet contained MCT, but was increased with the higher percentage of corn oil in the diet. Caloric intake was lowered, but its conversion to fat was higher on the high-fat diets. Serum triglycerides, but not glucose, were higher in both male and female rats fed the MCT compared to the corn-oil diet. These experiments suggest that the route by which nutrients are absorbed plays a role in regulating body-fat storage.
Article
• Triglycerides of saturated, medium-chain (6 to 12 carbons) fatty acids (MCT) and of saturated, long-chain (14 to 18 carbons) acids (LCT), which had been prepared from coconut and other palm kernel oils were studied in feeding experiments on rats receiving a purified diet with 30% casein. Their effects on growth, food and water intakes, weight maintenance requirements, and the testicular fat body were compared with those of lard and fat-free diets. • The body weights of freely-eating rats on lard were significantly higher than those of comparable animals on MCT, the latter being similar to those on fat-free diets. Those on LCT grew least. • The water consumptions of the rats on MCT were the highest; the Caloric intakes of those on the MCT and fat-free diets were similar and, on the average, slightly higher (not significantly) than that of the lard animals. The LCT animals ate and drank least. • The weight maintenance requirements of animals kept at constant weight by restricted feeding were significantly higher for the groups fed MCT and LCT than for the groups fed lard. Among the animals kept at constant weight, those on MCT and fat-free diets drank significantly more than those on LCT or lard. • The testicular fat bodies (which are roughly proportional to total neutral fat) were heaviest in relation to the body weight in animals on 30% lard and on LCT and lower for those on 30% MCT and fat-free diets. This was also true of animals on the same diets on restricted food intake.
Article
• Weanling male rats were maintained for 74 days on a purified, fat-free (FF) diet or similar ones containing 20% of saturated medium-chain (C6–12) triglycerides (MCT) or long-chain (C12–18) triglycerides (LCT). The diets were supplemented with zero, 0.1 or 2% of linoleic acid (LA). • Body weights of animals in the LA-deficient groups were similarly depressed with corresponding FF and MCT diets and more so with the LCT rations; with 2% of LA, rats in all groups had similar weights. • The deviations from normal of the organs in all LA-deficient groups included enlarged livers, adrenals, kidneys, heart ventricles and testicular-fat bodies. Thymus weights were reduced. Significant differences between corresponding LA-deficient groups fed the different triglycerides were noted; those fed MCT were usually similar to those receiving FF diets, whereas those fed LCT showed more pronounced deviations from normal. • It was concluded that MCT does not increase LA requirements in comparison with an FF diet and that LCT does. • Maintenance of control animals receiving reduced food intake led to organ-weight changes different from those found in LA deficiency: smaller livers, kidneys and heart ventricles than in normal animals and normal testicular-fat-body weights. This suggested that the organ-weight changes observed in the LA-deficient animals were not the result of partial inanition.
Effects of medium chain triglyceride on energy metabolism and body composition in the rat
  • D Travis
  • A Minenna
  • Frier
Travis D, Minenna A, Frier H. Effects of medium chain triglyceride on energy metabolism and body composition in the rat. Fed Proc 1979;38:561.