Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0948265 (metabolic syndrome)
 24,271 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

High-protein diets have been shown to promote weight loss, to improve glucose homeostasis and to increase energy expenditure and fat oxidation. We aimed to study whether leucine supplementation is able to mimic the alleviating effects of high-protein diets on metabolic syndrome parameters in mice fed high-fat diet. Male C57BL/6 mice were fed for 20 weeks with semisynthetic high-fat diets (20% w/w of fat) containing either an adequate (10% protein, AP) or high (50% protein, HP) amount of whey protein, or an AP diet supplemented with L-leucine corresponding to the leucine content of the HP diet (6% leucine, AP+L). Body weight and composition, energy expenditure, glucose tolerance, hepatic triacylglycerols (TG), plasma parameters as well as expression levels of mRNA and proteins in different tissues were measured. HP feeding resulted in decreased body weight, body fat and hepatic TG accumulation, as well as increased insulin sensitivity compared to AP. This was linked to an increased total and resting energy expenditure (REE), decreased feed energy efficiency, increased skeletal muscle (SM) protein synthesis, reduced hepatic lipogenesis and increased white fat lipolysis. Leucine supplementation had effects that were intermediate between HP and AP with regard to body composition, liver TG content, insulin sensitivity, REE and feed energy efficiency, and similar effects as HP on SM protein synthesis. However, neither HP nor AP+L showed an activation of the mammalian target of rapamycin pathway in SM. Leucine supplementation had no effect on liver lipogenesis and white fat lipolysis compared to AP. It is concluded that the essential amino acid leucine is able to mimic part but not all beneficial metabolic effects of HP diets.
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PMID:Comparison of high-protein diets and leucine supplementation in the prevention of metabolic syndrome and related disorders in mice. 2240 95

High-protein diets have been shown to alleviate detrimental effects of high-fat diets and this effect can be partially mimicked by dietary L-leucine supplementation. Here, we aimed to elucidate the early mechanisms and the specificity of leucine effects. We performed a 1-week trial with male C57BL/6 mice fed ad libitum with semisynthetic high-fat diets containing an adequate (10 % w/w, AP) or high (50 % w/w, HP) amount of whey protein, or supplemented with L-leucine corresponding to the leucine content within the HP diet (Leu) or supplemented with equimolar L-alanine (Ala). Food and water intake were monitored continuously using a computer-controlled monitor system and body composition changes were assessed using quantitative NMR. HP completely prevented the AP-induced accumulation of body fat. Leu and Ala resulted in a similar reduction of body fat accumulation which was intermediate between AP and HP. There were no significant effects on plasma glucose or insulin. Triacylglycerol content and gene expression of lipogenesis enzymes in liver as well as plasma cholesterol were reduced by HP compared to AP with Leu and Ala again showing intermediate effects. Body fat gain and liver triacylglycerols were strongly correlated with total energy intake. Water intake was rapidly increased by HP feeding and total water intake correlated strongly with total amino nitrogen intake. We concluded that the positive effects of high-protein diets on metabolic syndrome associated traits are acutely due to effects on satiety possibly linked to amino nitrogen intake and on the subsequent suppression of liver lipogenesis without evidence for a specific leucine effect.
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PMID:Dietary L-leucine and L-alanine supplementation have similar acute effects in the prevention of high-fat diet-induced obesity. 2284 80