RESUMO
Medium-chain triglycerides (MCT) are useful for increasing fat utilization during exercise. The highest rate of fat oxidation during submaximal exercise tends to precede the lactate threshold in untrained adults. In our previous study, blood lactate concentration was more than 4 mmol/L (onset of blood lactate) in recreational athletes during exercise at a workload corresponding to 60% peak O2 uptake (Vï½¥o2), which was below ventilation threshold. In the present study, we investigated the effect of 2 week of ingestion of food containing 6 g MCT on substrate oxidation during moderate-intensity (50% peak Vï½¥o2) exercise and high-intensity (70% peak Vï½¥o2) exercise in recreational athletes. For comparison, two experimental trials were conducted after participants had been administered isoenergic test foods (MCT-supplemented food with mainly maltodextrin-containing carbohydrate (MCT + CHO) or CHO) for 2 weeks, with a washout period between trials. Participants were instructed to perform cycle ergometer exercise at a workload corresponding to 50% peak Vï½¥o2 for 40 min followed by a workload corresponding to 70% peak Vï½¥o2 until exhaustion. Fat oxidation was significantly increased in the MCT + CHO trial (13.3 ± 2.7 g/40 min, mean ± SD, p < 0.05) during moderate-intensity exercise and the duration was extended significantly (23.5 ± 19.4 min, p < 0.05) during subsequent high-intensity exercise, compared with that observed in the CHO trial (fat oxidation; 11.7 ± 2.8 g/40 min, duration; 17.6 ± 16.1 min). In conclusion, continuous ingestion of 6 g MCT with maltodextrin could increase fat oxidation during moderate-intensity exercise and extend the duration of subsequent high-intensity exercise in recreational athletes, compared with the ingestion of isoenergic maltodextrin alone.
Assuntos
Tecido Adiposo/metabolismo , Exercício Físico/fisiologia , Polissacarídeos/metabolismo , Triglicerídeos/metabolismo , Adulto , Atletas , Metabolismo Energético , Feminino , Humanos , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Oxirredução , Adulto JovemRESUMO
In contrast to the consumption of long-chain triacylglycerols (LCT), consumption of medium- and long-chain triacylglycerols (MLCT) reduces the body fat and blood triacylglycerols (TAG) level in hypertriacylglycerolemic Chinese individuals. These responses may be affected by BMI because of obesity-induced insulin resistance. We aimed to compare the effects of consuming MLCT or LCT on reducing body fat and blood TAG level in hypertriacylglycerolemic Chinese subjects with different ranges of BMI. Employing a double-blind, randomized and controlled protocol, 101 hypertriacylglycerolemic subjects (including 67 men and 34 women) were randomly allocated to ingest 25-30 g/day MLCT or LCT oil as the only cooking oil for 8 consecutive weeks. Anthropometric measurements of body weight, BMI, body fat, WC, HC, blood biochemical variables, and subcutaneous fat area and visceral fat area in the abdomen were measured at week 0 and 8. As compared to subjects with BMI 24-28 kg/m(2) in the LCT group, corresponding subjects in the MLCT group showed significantly greater decrease in body weight, BMI, body fat, WC, ratio of WC to HC, total fat area and subcutaneous fat area in the abdomen, as well as blood TAG and LDL-C levels at week 8. Based upon our results, consumption of MLCT oil may reduce body weight, body fat, and blood TAG and LDL-C levels in overweight hypertriacylglycerolemic Chinese subjects but may not induce these changes in normal or obese hypertriacylglycerolemic subjects.
Assuntos
Tecido Adiposo/metabolismo , Hipertrigliceridemia/dietoterapia , Obesidade/tratamento farmacológico , Sobrepeso/tratamento farmacológico , Triglicerídeos/metabolismo , Povo Asiático , Índice de Massa Corporal , Gorduras Insaturadas na Dieta/administração & dosagem , Gorduras Insaturadas na Dieta/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/metabolismo , Sobrepeso/sangue , Sobrepeso/metabolismo , Triglicerídeos/administração & dosagem , Triglicerídeos/sangueRESUMO
A double blind clinical trial was carried out to clarify the effects of oil with medium- and long-chain triglyceride (MLCT) on body fat and blood lipid profiles in hypertriglyceridemic subjects. One-hundred-and-twelve subjects were enrolled and divided into two groups; those that consumed MLCT oil and those that consumed long-chain triglyceride (LCT) oil for 8 weeks. All subjects were requested to consume 25-30 g of the oils daily and maintain a fixed level of energy intake and exercise. Anthropometric and blood biochemical parameters were measured when the study was initiated and completed. The LCT group consisted of 50 subjects (34 men and 16 women), while the MLCT group consisted of 51 subjects (33 men and 18 women) who completed the study. Larger decreases in body weight, body mass index, waist circumference, body fat, total fat area and subcutaneous fat area in the abdomen and serum triglycerides, low-density lipoprotein cholesterol, apolipoprotein B, C2, C3 and E were observed in male subjects in the MLCT group than those in the LCT group. However, no significant differences in these parameters between the female subjects in the two groups were observed. Data from this study indicate that consumption of medium-and long-chain triglycerides can reduce body weight and body fat and improve blood lipid profiles in male hypertriglyceridemic subjects.
Assuntos
Tecido Adiposo , Gorduras Insaturadas na Dieta/uso terapêutico , Hipertrigliceridemia/dietoterapia , Lipídeos/sangue , Lipoproteínas/sangue , Caracteres Sexuais , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Registros de Dieta , Gorduras Insaturadas na Dieta/análise , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Triglicerídeos/química , Adulto JovemRESUMO
Two groups of Chinese hypertriacylglycerolemic subjects were recruited and randomized to medium- and long-chain triacylglycerols (MLCT) oil or long-chain triacylglycerols (LCT) oil. Two subgroups were divided by age at less or more 60 years in both groups. Both oils were consumed at 25-30 g daily for 8 weeks. Anthropometry, blood biochemicals, and computed tomography (CT) scanning were done at the initial and final times. In subjects of age less than 60 years on MLCT, the body weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), body fat, total fat area, and subcutaneous fat area were significantly lower than those of the initial values, and the change values in these indicators and visceral fat area lowered significantly as compared with those on LCT. The levels of apoB, apoA2, apoC2, and apoC3 decreased significantly, and the change in values in the levels of triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), apoA1, apoB, apoA2, apoC2, apoC3 were significantly lower on MLCT of age under 60 years as compared with those on LCT.
Assuntos
Gorduras na Dieta/farmacologia , Ácidos Graxos/química , Hipertrigliceridemia , Triglicerídeos/química , Triglicerídeos/farmacologia , Tecido Adiposo/efeitos dos fármacos , Adulto , Distribuição por Idade , Idoso , Apolipoproteínas/sangue , Povo Asiático , Glicemia/metabolismo , Colesterol/sangue , Ingestão de Energia , Feminino , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/enzimologia , Hipertrigliceridemia/fisiopatologia , Masculino , Atividade Motora , Triglicerídeos/sangueRESUMO
Medium-chain triacylglycerols (MCT) are known to hydrolyze readily and completely to fatty acids and to be metabolized more easily by beta-oxidation than long-chain triacylglycerols (LCT). Therefore, we investigated the effect of 2 wk of ingestion of food containing a small amount (6 g) of MCT on energy metabolism during moderate-intensity exercise and high-intensity exercise in recreational athletes. For comparison, the subjects were administered food containing MCT or LCT for 14 d, and were instructed to perform cycle ergometer exercise at a workload corresponding to 60% peak O(2) uptake (VO(2)) for 40 min followed by a workload corresponding to 80% peak VO(2) until exhaustion. Blood lactate concentration, VO(2), VCO(2), and rating of perceived exertion (RPE) were measured at rest and during exercise. The exercise time to exhaustion at a workload corresponding to 80% peak VO(2) was significantly (p<0.05) longer in the MCT trial (10.2+/-7.6 min; mean+/-SD) than in the LCT trial (5.8+/-3.3 min). Blood lactate concentration and RPE during exercise were significantly (p<0.05) lower after ingestion of MCT-containing food. Fat oxidation rate was higher and carbohydrate oxidation rate was lower during exercise in the MCT trial than in the LCT trial, but the differences were not significant. These results indicate that the ingestion of MCT-containing food may suppress utilization of carbohydrate for energy production because of increased utilization of fatty acids for generating energy. In conclusion, our data suggest that short-term ingestion of food containing a small amount of MCT suppresses the increase in blood lactate concentration and RPE during moderate-intensity exercise and extends the duration of subsequent high-intensity exercise, at levels higher than those achieved by ingestion of LCT-containing food.
Assuntos
Dióxido de Carbono/metabolismo , Exercício Físico/fisiologia , Ácido Láctico/sangue , Oxigênio/metabolismo , Resistência Física/efeitos dos fármacos , Triglicerídeos/farmacologia , Adulto , Ciclismo/fisiologia , Metabolismo dos Carboidratos/efeitos dos fármacos , Estudos Cross-Over , Metabolismo Energético/efeitos dos fármacos , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Triglicerídeos/administração & dosagem , Triglicerídeos/metabolismo , Adulto JovemRESUMO
Previous studies indicated that a medium-chain triacylglycerol (MCT) diet could inhibit body fat accumulation. It is also well established that exercise can reduce fat mass. However, the effects of a combination of MCT diet and exercise on reduction of fat mass have not been studied. Here we examined whether MCT diet and exercise intervention exert cooperative effects on body composition. Rats were assigned to 4 groups: 1. LCT diet, control (LCT-C); 2. MCT diet, control (MCT-C); 3. LCT diet, exercise (LCT-E); 4. MCT diet, exercise (MCT-E). After the 6-wk intervention, visceral fat mass was measured by CT scan and dissection, and energy expenditure was estimated for 24 h. The value of the visceral fat mass showed a significant correlation between CT scan and dissection (r=0.995, p<0.001). Visceral fat mass in the MCT-C group was lower than that in the LCT-C group. Furthermore, the fat-lowering effects were greater in the MCT-E group than that in either intervention alone. Thus significant effects of the MCT diet and exercise on the reduction of visceral fat mass were observed. Energy expenditure was significantly higher in the MCT-E group than in the other groups. Our present findings suggest that combined intervention of MCT diet and exercise has an additive effect on reduction of visceral and subcutaneous fat accumulation, and that this effect may be partially related to increased energy expenditure. However, future studies are necessary to define the relationship between energy expenditure and fat mass accumulation.
Assuntos
Tecido Adiposo/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Metabolismo Energético/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Triglicerídeos/farmacologia , Adipocinas/sangue , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/cirurgia , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Metabolismo Energético/fisiologia , Ácidos Graxos Monoinsaturados , Masculino , Condicionamento Físico Animal/métodos , Óleos de Plantas/administração & dosagem , Óleo de Brassica napus , Ratos , Ratos Wistar , Tomografia Computadorizada por Raios X/métodosRESUMO
The present study was examined the therapeutic effect of medium-chain triacylglycerol (MCT) in protein-energy malnutrition (PEM). Wistar rats were fed low protein diet containing 70 g/kg of long-chain triacylglycerol (LCT) or MCT for 31 days. The serum albumin concentration in rats fed MCT diet (2.88 +/- 0.04 g/dl) were significantly higher compared with those fed LCT diet (2.72 +/- 0.04 g/dl) at day 31. Nitrogen balance was higher in rats fed MCT diet (54.1 +/- 2.3 mg/day) compared with those fed LCT diet (45.4 +/- 2.4 mg/day) during d 10-12. These results suggest that MCT effectively elevates serum albumin concentration and improves nitrogen balance in malnourished rats.
RESUMO
We have reported previously that dietary medium-chain triacylglycerol (MCT) improved serum albumin concentration and protein balance in malnourished rats. To clarify the mechanisms for this effect of MCT, hepatic messenger RNA levels of gluconeogenic enzymes, pyruvate dehydrogenase (PDH) and alanine aminotransferase (ALT) were measured in rats fed low-protein diets containing either MCT or isocaloric long-chain triacylglycerol (LCT) for 2 wk. The serum albumin concentration in rats fed the MCT diet was significantly higher compared with those fed the LCT diet. Serum free fatty acids and ketone body fraction were higher in rats fed MCT compared with those fed the LCT diet. The hepatic mRNA level of PDH was significantly lower in rats fed MCT than those fed LCT. But, there was no significant difference between the two groups in mRNA of gluconeogenic enzymes or ALT. These results suggest that ketone bodies, which are an alternative energy source and might spare blood glucose, increase by MCT feeding, and the reason for the PEM (protein-energy malnutrition)-improving effect of MCT is not caused by suppression of gluconeogenesis.
Assuntos
Gorduras na Dieta/farmacologia , Gluconeogênese , Fígado/efeitos dos fármacos , Desnutrição Proteico-Calórica/enzimologia , RNA Mensageiro/metabolismo , Triglicerídeos/farmacologia , Actinas/genética , Actinas/metabolismo , Tecido Adiposo/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Proteínas Sanguíneas/metabolismo , Brassica rapa , Ácidos Graxos não Esterificados/sangue , Corpos Cetônicos/sangue , Fígado/enzimologia , Óleos de Plantas/farmacologia , Desnutrição Proteico-Calórica/tratamento farmacológico , Complexo Piruvato Desidrogenase/sangue , Ratos , Aumento de Peso/efeitos dos fármacosRESUMO
Medium-chain fatty acids (MCFA) have attracted attention as part of a healthy diet, because they are absorbed and transported directly into the liver via the portal vein, metabolized rapidly by beta-oxidation, and increase diet-induced thermogenesis. Because medium-chain triacylglycerols (MCT) containing only MCFA has a few weak points as frying oils, we have developed medium- and long-chain triacylglycerols (MLCT). MLCT is produced by lipase-catalyzed enzymatic transesterification. Recently, long-term clinical trials have demonstrated that MLCT and MCT result in less body fat-deposition. MLCT oil (Trade name: Healthy Resseta) is safe and can be substitute for common edible vegetable oils. Healthy Resseta has been approved as FOSHU (Food for Specified Health Use), by the Ministry of Health, Labour and Welfare of Japan in December 2002 for use as a cooking oil with a suppressing effect on body fat accumulation. Healthy Resseta is widely sold in Japan.
Assuntos
Gorduras Insaturadas na Dieta/metabolismo , Ácidos Graxos/metabolismo , Tecido Adiposo/patologia , Ácidos Graxos/química , Humanos , Modelos Biológicos , Obesidade/dietoterapiaRESUMO
A study was conducted to investigate the short-term safety of dietary conjugated linoleic acid (CLA) in overweight Japanese male volunteers. The study design was a randomized, double-blind placebo-controlled trial including 60 healthy overweight volunteers (body mass index (BMI), 25 approximately 35 kg/m(2)). The subjects were randomly assigned to three groups: 5.4 g CLA-triacylglycerol (3.4 g as CLA), 10.8 g CLA-triacylglycerol (6.8 g as CLA) and placebo (10.8 g safflower oil) daily for 12 weeks. The CLA-triaclyglycerol contained 9c,11t- and 10t,12c-isomers at an equal proportion. The safety was evaluated by analyses of blood parameters and by clinical examinations at the baseline, and at 6 and 12 weeks, including vital signs and adverse effects. All subjects completed the study. The occurrence of adverse events tended to be higher in the CLA groups than in the placebo group, but all of the adverse events were mild to moderate, within normal ranges, and temporary. Serum aspartate aminotransferase (AST) activity did not differ significantly between the groups at 12 weeks, but in the high CLA group it was slightly increased from the baseline. Serum alanine aminotransferase (ALT) activity was higher in the high CLA group than in the placebo group after 12 weeks and was higher than at the baseline in both CLA groups. However, statistical analysis of the population of apparently healthy volunteers who had normal blood parameters at the baseline revealed that AST and ALT levels did not differ significantly among the 3 groups at 12 weeks. Moreover, no clinically significant changes in vital signs were observed in any of the groups. These results indicate that CLA at a dose of 3.4 g/day is a safe dietary level in healthy Japanese populations in terms of the parameters examined.
Assuntos
Ácidos Linoleicos Conjugados/efeitos adversos , Ácidos Linoleicos Conjugados/uso terapêutico , Obesidade/dietoterapia , Sobrepeso , Adulto , Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais/efeitos adversos , Exercício Físico/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Japão , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/fisiopatologia , Sobrepeso/efeitos dos fármacos , PlacebosRESUMO
This study investigated the effects of a liquid meal containing medium- and long-chain triacylglycerols (MLCT) on diet-induced thermogenesis (DIT) and was conducted in double-blind cross-over manner. Twenty subjects participated in this examination. The subjects consumed the liquid meal, which was made with 14 g of canola oil (LCT, long-chain triacylglycerols) or MLCT containing about 12% medium-chain fatty acids (MCFA). Oxygen consumption and carbon dioxide production were measured by indirect calorimetry. Resting energy expenditure (REE) was determined based on there parameters, applying the equation of Weir. Increase in DIT after ingesting the liquid meal with MLCT during 6h was significantly greater than with LCT (P<0.05). The results suggest that the substitution of MLCT for cooking oil is useful to control body weigh and fat in subjects.
Assuntos
Dieta , Termogênese/efeitos dos fármacos , Triglicerídeos/química , Triglicerídeos/farmacologia , Adulto , Ácidos Graxos/farmacologia , Feminino , Humanos , Masculino , Oxigênio/metabolismo , RespiraçãoRESUMO
We investigated the antihypertensive effect and safety of alpha-linolenic acid (ALA) in human subjects. In Experiment 1, subjects with high-normal blood pressure and mild hypertension ingested bread containing 14 g of common blended oil (control oil) or ALA-enriched oil for 12 weeks. The test oil contained 2.6g/14 g of ALA. The subjects ingested strictly controlled meals during the study period. Systolic blood pressure was significantly lower in the ALA group than in the control group after ingestion of the test diet for 4, 8 and 12 weeks. Diastolic blood pressure was significantly lower in the ALA group than in the control group after ingestion of the test diet for 12 weeks. In Experiment 2, we evaluated the safety of high intake of ALA (7.8 g/d), particularly its effects on oxidation in the body and blood coagulation. Normotensive, high-normotensive and mildly hypertensive subjects ate bread that contained 42 g of the control oil or the test oil for 4 weeks. No significant difference was noted in the lipid peroxide level, high-sensitive C-reactive protein level, plasma prothrombin time or activated partial thromboplastin time between the two groups. No abnormal changes were noted after test diet ingestion on blood test or urinalysis, and no adverse event considered to have been induced by the test oil was observed in Experiment 1 and 2. These results suggest that ALA have an antihypertensive effect with no adverse effect in subjects with high-normal blood pressure and mild hypertension.
Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Dieta , Hipertensão/dietoterapia , Ácido alfa-Linolênico/uso terapêutico , Adulto , Bebidas Alcoólicas , Peso Corporal/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão/sangue , Hipertensão/patologia , Hipertensão/urina , Masculino , Pessoa de Meia-Idade , Segurança , Cloreto de Sódio/farmacologia , Ácido alfa-Linolênico/efeitos adversosRESUMO
We have reported previously that randomly interesterified triacylglycerol containing medium- and long-chain fatty acids in the same glycerol molecule (MLCT) resulted in significantly lower body fat accumulation and higher hepatic fatty acid oxidation than from long-chain triacylglycerol (LCT) in rats. To understand the metabolic changes occurring in white adipose tissue, the fatty acid oxidation and synthesis, and the adipocytokine level were measured in rats fed with MLCT or LCT for 2 weeks. In comparison with LCT, MLCT lowered not only the fatty acid synthase and glycerol-3-phosphate dehydrogenase activities in perirenal adipose tissue, but also the serum insulin and leptin levels, in addition to significantly reducing the body fat accumulation. In contrast, fatty acid oxidation measured as the carnitine palmitoyltransferase activity in the tissue was significantly higher in the MLCT-fed rats than in the LCT-fed rats. It seems that the altered fatty acid metabolism in adipose tissue per se was also responsible for the lower adiposity by dietary MLCT.
Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Ácidos Graxos/farmacologia , Triglicerídeos/farmacologia , Tecido Adiposo Branco/metabolismo , Animais , Sequência de Bases , Primers do DNA , Ácidos Graxos/metabolismo , Masculino , Oxirredução , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triglicerídeos/químicaRESUMO
In our previous studies, medium- and long-chain triacylglycerols (MLCT), randomly interesterified triacylglycerols containing medium-chain and long-chain fatty acids in the same glycerol molecule, significantly reduced body fat accumulation in humans and rats. To clarify mechanism(s) for this effect of MLCT, we measured energy expenditure and hepatic fatty acid metabolism in rats by comparison with long-chain triacylglycerols (LCT) or medium-chain triacylglycerols (MCT). MLCT, compared with LCT, showed significantly lower body fat accumulation, higher 24-h energy expenditure and acyl-CoA dehydrogenase activity measured using octanoyl-CoA as a substrate, and similar lipogenic activity. MCT, compared with LCT, showed significantly higher energy expenditure, but fat accumulation was comparable. Additionally, MCT exhibited significantly higher lipogenic activity than the other oils. These data suggest that enhancement of energy expenditure and medium-chain fatty acids (MCFA) oxidation without activating de novo lipogenesis are responsible at least for the lower body fat accumulation in rats fed MLCT. The activation of hepatic lipogenesis by excessive intake of MCFA might counteract their preventive effects on body fat accumulation.
Assuntos
Metabolismo Energético , Ácidos Graxos/metabolismo , Fígado/metabolismo , Triglicerídeos/metabolismo , Acil-CoA Desidrogenase/metabolismo , Animais , Distribuição da Gordura Corporal , Esterificação , Ácidos Graxos/química , Lipogênese , Masculino , Ratos , Ratos Sprague-Dawley , Triglicerídeos/químicaRESUMO
The physiological activity and effect on lipid metabolism of four types of structured lipids (SLs), that contain caprylic acid (C8) and either eicosapentaenoic (EPA) or docosahesaenoic acid (DHA), were evaluated in male Wistar rats fed experimental diets containing 7% (wt %) of each SL and 3% (wt %) soybean oil for 28 days. Control rats were fed a diet containing 10% (wt %) soybean oil. The relative perirenal adipose tissue weights of rats fed D-8-8 and 8-D-8 diets were significantly lower than those of other groups. We observed significantly lower serum cholesterol concentrations in rats fed SLs than those of control group over experimental period. The serum lipids concentrations in rats fed diets containing SLs were significantly lower P < 0.05) than those of soybean oil group. The fatty acid compositions of WAT did not reflect the structural differences in the triglyceride. These results suggest that the physiological effects of the SLs used in this study were due to the fatty acids rather than the structural specificity. Therefore, further study will be needed to ascertain the most desirable structural configuration.
Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Metabolismo dos Lipídeos , Lipídeos/sangue , Fígado/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Cinética , Lipase/metabolismo , Lipídeos/farmacologia , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos WistarRESUMO
The purpose of this study is to examine the effects of highly purified structured lipids on serum and liver lipid profiles in rats. We also investigated in vitro hydrolysis of lipid emulsions by porcine pancreas. Hydrolysis rates of medium chain (M)-linoleic (L)-medium chain (M) types were 2 to 3 times higher than those of L-M-L types. The diet containing structured lipids or corn oil was administered to rats for 4 weeks. There were no significant differences in growth and food efficiency. Serum cholesterol levels were significantly lower (P<0.05) in the 2-octanoyl-1,3-dilinoleoyl-glycerol, 2-linoleoyl-1,3-didecanoyl-glycerol, and 2-decanoyl-1,3-dilinoleoyl-glycerol groups than in the corn-oil group. Serum triglyceride levels were significantly lower (P<0.05) in rats fed L-M-L types than those in the other groups. Serum non-esterified fatty acid (NEFA) and beta-hydroxybutylate levels were significantly higher (P<0.01) in rats fed M-L-M types than those of the other groups. These results indicate that the feeding of highly purified L-M-L types could effectively improve serum and liver lipid profiles and that M-L-M types may be a preferable substrate for the pancreas and contribute to energy supply in rats.
Assuntos
Gorduras na Dieta/farmacologia , Ácidos Graxos/metabolismo , Ácido Linoleico/metabolismo , Ácido 3-Hidroxibutírico/sangue , Ração Animal , Animais , Colesterol/sangue , Emulsões , Ácidos Graxos/sangue , Ácidos Graxos/farmacologia , Ácidos Graxos não Esterificados/sangue , Hidrólise , Ácido Linoleico/farmacologia , Masculino , Pâncreas/metabolismo , Ratos , Ratos Wistar , Suínos , Triglicerídeos/sangueRESUMO
We investigated whether a structured medium- and long-chain triacylglycerols (MLCT) diet could decrease accumulation of body fat in healthy humans. The study was conducted under a double-blind randomized design. Ninety-three subjects participated in this study. However, 10 subjects could not consume the specified meal, and one subject wished to opt out. Consequently, the study included 82 subjects. The experimental subjects consumed the test bread, which was made with 14 g of MLCT containing 1.7 g MCFA, daily at breakfast during the study period of 12 weeks, and the control subjects consumed bread made with long-chain triacylglycerols (LCT). All subjects consumed the same standard packaged meals. Body composition parameters were body weight, total body fat and abdominal fat, and blood analyses included serum cholesterol, triacylglycerols and phospholipids. Significant decreases of body weight, the amount of body fat, subcutaneous and visceral fat were noted in the MLCT group as compared with those of the LCT group for 12 weeks (P<0.05). Furthermore, a significant decrease in serum total cholesterol was noted in the MLCT group as compared with that of the LCT group at 8 weeks (P<0.05). However, other serum parameters were not different between the MLCT and LCT groups. The results suggest that the daily intake of MLCT diet could result in a reduction in body weight and in accumulation of body fat, and, moreover, it could reduce serum total cholesterol.
Assuntos
Tecido Adiposo/metabolismo , Composição Corporal/efeitos dos fármacos , Colesterol/sangue , Gorduras na Dieta/administração & dosagem , Triglicerídeos/administração & dosagem , Tecido Adiposo/crescimento & desenvolvimento , Adulto , Composição Corporal/fisiologia , Constituição Corporal/fisiologia , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Gorduras na Dieta/metabolismo , Método Duplo-Cego , Metabolismo Energético , Humanos , Pessoa de Meia-Idade , Obesidade/dietoterapia , Obesidade/metabolismo , Obesidade/prevenção & controle , Fosfolipídeos/sangue , Triglicerídeos/química , Triglicerídeos/metabolismo , Redução de PesoRESUMO
This study compared the serum lipid concentrations after a single dose of medium-chain triglycerides (MCT) or long-chain triglycerides (LCT) between individuals grouped according to the body mass index (BMI). Twenty-five males participated as volunteers, the test diet containing 10 g of MCT or LCT. Blood samples were collected up to 6 h after the intake of a test diets. The LCT diet resulted in significantly greater increases in areas under the curves (AUCs) for serum and chylomicron triglyceride in the BMI > or = 23 kg/m2 group than those in the BMI < 23 kg/m2 group. The magnitude of response after intake of the MCT diet by the BMI > or = 23 kg/m2 group was significantly lower than that after the LCT diet. These results suggest that, in subjects with BMI > or = 23 kg/m2, the intake of MCT is preferable to that of LCT for maintaining postprandial triglyceride at a low concentration.
Assuntos
Período Pós-Prandial/fisiologia , Triglicerídeos/metabolismo , Triglicerídeos/farmacologia , Animais , Análise Química do Sangue , Índice de Massa Corporal , Colesterol/sangue , Estudos Cross-Over , Dieta , Gorduras Insaturadas na Dieta/farmacologia , Método Duplo-Cego , Humanos , Lipídeos/sangue , Lipoproteínas/sangue , Masculino , RatosRESUMO
We found previously that the ingestion of margarine containing medium-chain triacylglycerols (MCT) resulted in a significant increase in postprandial thermogenesis when compared with long-chain triacylglycerols (LCT). Diets that included margarine containing MCT and LCT were compared for 12 weeks in 73 subjects to investigate the effects on body weight, body fat, areas of subcutaneous and visceral fat, serum total cholesterols, triglycerides, lipoproteins, plasma glucose, serum insulin, total ketone bodies, and the activities of aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyltranspeptidase. We conducted a double-blind, controlled study and used blended rapeseed oil and soybean oil (LCT) as a comparison. Two groups ingested 2100-2400 kcal/day of energy, 65-73 g/day of total fat, and 14 g/day of test margarine (5 g/day of MCT or LCT). The subjects on the MCT diet demonstrated significant decreases in body fat weight (- 3.8 +/- 2.4 kg vs - 2.4 +/- 1.7 kg; MCT vs LCT, mean +/- SD), subcutaneous fat (- 38.2 +/- 29.9 cm(2) vs - 22.6 +/- 19.3 cm(2)), and visceral fat (- 12.2 +/- 11.2 cm(2) vs - 1.6 +/- 12.8 cm(2)) after 12 weeks. There were no clinical differences in measured blood parameters. We suggest that the postprandial increase in thermogenesis and control of postprandial triglyceride levels may explain these results.
Assuntos
Tecido Adiposo/anatomia & histologia , Composição Corporal , Margarina , Triglicerídeos/administração & dosagem , Adulto , Glicemia , Estatura , Peso Corporal , Ingestão de Alimentos , Metabolismo Energético , Feminino , Humanos , Insulina/sangue , Corpos Cetônicos/sangue , Masculino , Pessoa de Meia-Idade , Política Nutricional , Período Pós-Prandial , Tela SubcutâneaRESUMO
The objective of this study was to investigate effects of dietary medium-chain triacylglycerols (MCTs) on serum lipid levels, liver function, and hepatic fat accumulations in healthy men. Eleven subjects consumed 2200-2600 kcal daily, of which 70-80 g was fat; the fat included 40 g of MCTs or else 40 g of long-chain triacylglycerols (blended vegetable oil). The diet was followed for 4 weeks in this controlled double-blind study. At the end of the experiment, significant differences were not found in the concentrations of serum total cholesterol, very low density lipoprotein cholesterol, low density lipoprotein cholesterol, and high density lipoprotein cholesterol between the groups. Serum triglycerol levels were not significantly different in the groups. Adverse effects from ingestion of MCTs on liver functions, the liver-to-spleen ratio on computed tomography (an index of fatty liver), or results of blood tests were not seen. The results suggest that the long-term effects of dietary MCTs on serum cholesterol were similar to those of unsaturated fatty acids found abundantly in vegetable oil, and that consumption of MCTs in the amount of 40 g/day for a month does not cause liver fat accumulation or liver dysfunction.