Zheng Wenxuan, Li Ruiding, Zhou Yang, Shi Fengcui, Song Yao, Liao Yanting, Zhou Fan, Zheng Xiaohua, Lv Jingwen, Li Quanyang
School of Light Industry and Food Engineering, Guangxi University, Nanning, China.
Wangdingdi Hospital, Tianjin, China.
Front Nutr. 2022 Nov 3;9:1051964. doi: 10.3389/fnut.2022.1051964. eCollection 2022.
In the protein nutrition strategy of middle-aged and elderly people, some believe that low protein is good for health, while others believe high protein is good for health. Facing the contradictory situation, the following hypothesis is proposed. There is a process of change from lower to higher ratio of protein nutritional requirements that are good for health in the human body after about 50 years of age, and the age at which the switch occurs is around 65 years of age. Hence, in this study, 50, 25-month-old male rats were randomly divided into five groups: Control (basal diet), LP (low-protein diet with a 30% decrease in protein content compared to the basal diet), HP (high-protein diet with a 30% increase in protein content compared to the basal diet), Model 1 (switched from LP to HP feed at week 4), and Model 2 (switched from LP to HP feed at week 7). After a total of 10 weeks intervention, the liver and serum samples were examined for aging-related indicators, and a newly comprehensive quantitative score was generated using principal component analysis (PCA). The effects of the five protein nutritional modalities were quantified in descending order: Model 1 > HP > LP > Control > Model 2. Furthermore, the differential metabolites in serum and feces were determined by orthogonal partial least squares discriminant analysis, and 15 differential metabolites, significantly associated with protein intake, were identified by Spearman's correlation analysis ( < 0.05). Among the fecal metabolites, 10 were positively correlated and 3 were negatively correlated. In the serum, tyrosine and lactate levels were positively correlated, and acetate levels were negatively correlated. MetaboAnalyst analysis identified that the metabolic pathways influenced by protein intake were mainly related to amino acid and carbohydrate metabolism. The results of metabolomic analysis elucidate the mechanisms underlying the preceding effects to some degree. These efforts not only contribute to a unified protein nutrition strategy but also positively impact the building of a wiser approach to protein nutrition, thereby helping middle-aged and older populations achieve healthy aging.
在中老年人的蛋白质营养策略方面，一些人认为低蛋白有益健康，而另一些人则认为高蛋白有益健康。面对这种矛盾的情况，提出了以下假设。人体在50岁左右后，存在一个从有利于健康的较低蛋白质营养需求比例向较高比例转变的过程，而转变发生的年龄大约在65岁左右。因此，在本研究中，将50只25月龄的雄性大鼠随机分为五组：对照组（基础日粮）、LP组（低蛋白日粮，蛋白质含量比基础日粮降低30%）、HP组（高蛋白日粮，蛋白质含量比基础日粮增加30%）、模型1组（在第4周从LP饲料切换到HP饲料）和模型2组（在第7周从LP饲料切换到HP饲料）。经过总共10周的干预后，对肝脏和血清样本进行衰老相关指标检测，并使用主成分分析（PCA）生成一个新的综合定量评分。对五种蛋白质营养模式的效果进行量化，从高到低依次为：模型1组>HP组>LP组>对照组>模型2组。此外，通过正交偏最小二乘法判别分析确定血清和粪便中的差异代谢物，并通过Spearman相关性分析（<0.05）鉴定出15种与蛋白质摄入显著相关的差异代谢物。在粪便代谢物中，10种呈正相关，3种呈负相关。在血清中，酪氨酸和乳酸水平呈正相关，乙酸水平呈负相关。MetaboAnalyst分析确定受蛋白质摄入影响的代谢途径主要与氨基酸和碳水化合物代谢有关。代谢组学分析结果在一定程度上阐明了上述作用的潜在机制。这些工作不仅有助于形成统一的蛋白质营养策略，还对构建更明智的蛋白质营养方法产生积极影响，从而帮助中老年人群实现健康老龄化。
