Animal and plant proteins and glucose metabolism

摘要 近65%的美国成年人积极尝试增加蛋白质摄入量， 食用富含天然蛋白质的食物以及用蛋白质分离物强化的食物和饮料， 改善他们的健康。然而，最近的人口研究数据显示， 2型糖尿病（T2 D）的发病率与糖尿病的发病率有关。这 不良影响可能是特定的蛋白质消耗的类型，因为一些研究已经 发现高动物蛋白，但不高植物蛋白，消费与 增加T2 D风险。有实验证据表明，在人类和 小鼠，以支持膳食蛋白质摄入量和代谢功能障碍之间的因果关系。 然而，慢性高蛋白摄入对葡萄糖稳态的影响及其机制尚不清楚。 引起蛋白质介导的代谢功能障碍的原因尚不清楚。的原因（S） 在高动物蛋白和高植物蛋白之间观察到的代谢效应的差异 消费量也不清楚，但可能是由于氨基酸组成的差异 以及动物和植物蛋白本身和/或其生物基质的结构，其包括 富含蛋白质的植物性食物中含有复杂的细胞壁、凝集素和蛋白酶抑制剂， 微生物接近蛋白质和/或诱导有益代谢物的微生物产生， 例如短链脂肪酸。该提案的目的是确定高- 蛋白质饮食，其中蛋白质摄入量的增加来自不同来源（动物与 植物和富含蛋白质的天然食物与蛋白质分离物）对：i）肝脏和肌肉胰岛素敏感性; iii）葡萄糖的24小时血浆浓度曲线， 糖调节激素和蛋白质衍生的代谢产物，据称引起代谢 功能障碍我们的首要假设是，富含动物或植物蛋白的饮食 分离物，或富含动物蛋白的全食，但不是富含植物蛋白的全食， 可导致胰岛素抵抗的血浆激素和蛋白质代谢物的改变 并刺激肝葡萄糖产生，从而提高24小时血糖浓度。

Abstract Nearly 65% of adults in the United States actively try to increase their protein intake by consuming naturally protein-rich foods and foods and drinks fortified with protein isolates to improve their health. However, data from recent population studies have shown high protein consumption is associated with an increased risk of developing type 2 diabetes (T2D). This adverse effect might be specific to the type of protein consumed because several studies have found high animal protein, but not high plant protein, consumption was associated with increased T2D risk. There is experimental evidence from studies conducted in people and in mice to support a causal relationship between dietary protein intake and metabolic dysfunction. However, the effect of chronic high protein intake on glucose homeostasis and the mechanisms that cause protein-mediated metabolic dysfunction are not known. The reason(s) for the differences in the metabolic effects observed between high animal protein and high plant protein consumption are also not known, but could be due to differences in the amino acid composition and structure of animal and plant proteins per se and/or their biological matrix, which includes complex cell walls, lectins, and protease inhibitors in protein-rich plant foods, that can impair gut microbial access to proteins and/or induce the microbial production of beneficial metabolites, such as short-chain fatty acids. The goal of this proposal is to determine the effect of a high- protein diet in which the increase in protein intake is derived from different sources (animal vs plant and protein-rich whole foods vs protein isolates) on: i) liver and muscle insulin sensitivity; ii) the metabolic response to a meal, and iii) 24-h plasma concentration profiles of glucose, glucoregulatory hormones, and protein-derived metabolites purported to cause metabolic dysfunction. Our overarching hypothesis is that diets enriched with either animal or plant protein isolates, or animal protein-rich whole foods, but not plant protein-rich whole foods, cause alterations in the plasma hormones and protein metabolites that can cause insulin resistance and stimulate hepatic glucose production, thereby raising 24-h plasma glucose concentration.