Torre-Villalvazo Ivan, Tovar Armando R, Ramos-Barragán Victoria E, Cerbón-Cervantes Marco Antonio, Torres Nimbe
Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México, DF, 14000.
J Nutr. 2008 Mar;138(3):462-8. doi: 10.1093/jn/138.3.462.
Chronic consumption of high-fat or -carbohydrate diets is associated with the development of obesity; however, it is not well established whether dietary protein plays a role in the development of abnormalities of lipid metabolism that occur during obesity. To determine the effect of different types of protein during diet-induced obesity on hepatic and adipocyte lipid metabolism, rats were fed casein (CAS) or soy (SOY) protein diets with 5% fat or high-fat diets with 25% fat (HF-CAS and HF-SOY) for 180 d. Rats fed soy diets had lower hepatic sterol regulatory element binding protein-1 (SREBP-1) expression and higher SREBP-2 expression than those fed casein diets, leading to less hepatic lipid deposition. On the other hand, long-term HF-SOY consumption prevented hyperleptinemia in comparison with rats fed HF-CAS. Rats fed soy protein diet showed higher adipocyte perilipin mRNA expression and smaller adipocyte area than those fed casein diets, which was associated with a lower body fat content. Furthermore, the lipid droplet area in brown adipose tissue was significantly lower in rats fed soy diets than in those fed casein diets and it was associated with higher uncoupling protein-1 (UCP-1) expression. As a result, rats fed the soy diets gained less weight than those fed the casein diets, in part due to an increase in the thermogenic capacity mediated by UCP-1. These results suggest that the type of protein consumed and the presence of fat in the diet modulate lipid metabolism in adipose tissue and liver.
长期食用高脂肪或高碳水化合物饮食与肥胖的发生有关；然而，饮食蛋白质是否在肥胖期间发生的脂质代谢异常发展中起作用尚未明确。为了确定饮食诱导肥胖期间不同类型蛋白质对肝脏和脂肪细胞脂质代谢的影响，将大鼠分别喂食含5%脂肪的酪蛋白（CAS）或大豆（SOY）蛋白饮食或含25%脂肪的高脂肪饮食（HF-CAS和HF-SOY），持续180天。与喂食酪蛋白饮食的大鼠相比，喂食大豆饮食的大鼠肝脏固醇调节元件结合蛋白-1（SREBP-1）表达较低，而SREBP-2表达较高，导致肝脏脂质沉积较少。另一方面，与喂食HF-CAS的大鼠相比，长期食用HF-SOY可预防高瘦素血症。与喂食酪蛋白饮食的大鼠相比，喂食大豆蛋白饮食的大鼠脂肪细胞周脂素mRNA表达较高，脂肪细胞面积较小，这与较低的体脂含量有关。此外，喂食大豆饮食的大鼠棕色脂肪组织中的脂滴面积显著低于喂食酪蛋白饮食的大鼠，这与较高的解偶联蛋白-1（UCP-1）表达有关。结果，喂食大豆饮食的大鼠比喂食酪蛋白饮食的大鼠体重增加较少，部分原因是UCP-1介导的产热能力增加。这些结果表明，摄入的蛋白质类型和饮食中脂肪的存在会调节脂肪组织和肝脏中的脂质代谢。
