Pedroso João Alfredo B, Nishimura Luciana Sigueta, de Matos-Neto Emídio Marques, Donato Jose, Tirapegui Julio
Department of Food Science and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil; Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
Cell Biochem Funct. 2014 Jun;32(4):326-32. doi: 10.1002/cbf.3017. Epub 2013 Dec 11.
Several studies have highlighted the potential of leucine supplementation for the treatment of metabolic diseases including type 2 diabetes and obesity. Caloric restriction is a common approach to improve the health in diabetic and obese subjects. However, very few studies assessed the effects of leucine supplementation in calorie-restricted animals. Rats were subjected to a 30% calorie-restricted diet for 6 weeks to study the effects of leucine supplementation on protein status markers and lipid metabolism. Caloric restriction reduced the body weight. However, increased leucine intake preserved body lean mass and protein mass and improved protein anabolism as indicated by the increased circulating levels of albumin and insulin-like growth factor-1 (IGF-1), and the liver expression of albumin and IGF-1 messenger RNA. Leucine supplementation also increased the circulating levels of interleukin-6 and leptin but did not affect the tumour necrosis factor-α and monocyte chemotactic protein-1 concentrations. Ketone bodies were increased in rats consuming a leucine-rich diet, but we observed no changes in cholesterol or triglycerides concentrations. Caloric restriction reduced the liver expression of peroxisome proliferator activated receptor-α and glucose-6-phosphatase, whereas leucine supplementation increased the liver expression of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA) reductase and sterol regulatory element-binding transcription factor 1. A leucine-rich diet during caloric restriction preserved whole body protein mass and improved markers of protein anabolism. In addition, leucine modulated the hepatic lipid metabolism. These results indicate that increased leucine intake may be useful in preventing excessive protein waste in conditions of large weight loss.
多项研究强调了补充亮氨酸在治疗包括2型糖尿病和肥胖症在内的代谢性疾病方面的潜力。热量限制是改善糖尿病和肥胖受试者健康状况的常用方法。然而，很少有研究评估补充亮氨酸对热量限制动物的影响。对大鼠进行为期6周的30%热量限制饮食，以研究补充亮氨酸对蛋白质状态标志物和脂质代谢的影响。热量限制降低了体重。然而，亮氨酸摄入量的增加保留了身体瘦体重和蛋白质质量，并改善了蛋白质合成代谢，这表现为循环中白蛋白和胰岛素样生长因子-1（IGF-1）水平升高，以及肝脏中白蛋白和IGF-1信使核糖核酸的表达增加。补充亮氨酸还增加了白细胞介素-6和瘦素的循环水平，但不影响肿瘤坏死因子-α和单核细胞趋化蛋白-1的浓度。食用富含亮氨酸饮食的大鼠酮体增加，但我们观察到胆固醇或甘油三酯浓度没有变化。热量限制降低了过氧化物酶体增殖物激活受体-α和葡萄糖-6-磷酸酶的肝脏表达，而补充亮氨酸增加了3-羟基-3-甲基戊二酰辅酶A还原酶（HMG-CoA还原酶）和固醇调节元件结合转录因子1的肝脏表达。热量限制期间富含亮氨酸的饮食保留了全身蛋白质质量，并改善了蛋白质合成代谢的标志物。此外，亮氨酸调节肝脏脂质代谢。这些结果表明，增加亮氨酸摄入量可能有助于在大幅体重减轻的情况下防止过多的蛋白质流失。
