Metabolic impact of dietary whey proteins, peptides and amino acids thereof on the heat-shock proteins (HSPs) and associated parameters in rats

Abstract

The whey protein (WP) have shown to have various properties and health effects. We recently reported that WP was able to increase expression of HSP70 in various tissues. The heat-shock proteins (HSP) are composed of several families that represent a protective system that favors cell resistance and tolerance in the face of adverse conditions in the body. It is believed that the high content of branched chain amino acids (BCAAs), is a major factor involved in the ability of WP increase in HSP70. The objective of this study is to investigate the influence of the consumption of whey protein as protein source in the diet on the expression of other HSPs, and also check the influence of amino acids and peptides present in the WP in HSPs and associated parameters. Methods: We will use the first experiment, 48 male rats were divided primarily into 2 groups: sedentary and exercised. Each group is divided into three dietary groups (receiving AIN 93-G, with protein replacement): whey protein concentrate (WPC), whey protein hydrolyzate (WPH) and casein (CAS) as a control. The animals of group exercised will be submitted to exercise on a treadmill as a source of heat stress. The following parameters are determined: free amino acids in the plasma, HSP25, HSP60, HSP90, AHA1, DHFR, NOS, VEGF, PI3-Kinase, BCKDH, SOD, Catalase, GPx, p-AKT, GFAT, OGT, HSF1, HSF1 phosphorylated. In Experiment 2, we use 90 male rats were divided into 10 groups, which are gavados one of the following amino acids: leucine, valine, isoleucine, glutamine and arginine, or peptides: isoleucyl-leucine, leucyl-isoleucine, valyl-leucine, leucyl-valine, compared to WPH. After the exercise as a source of stress, the following parameters are determined: free amino acids in plasma, HSP25, HSP60, HSP90, HSP70, AHA1, DHFR, NOS, VEGF, PI3-Kinase, BCKDH, SOD, catalase, GPx, p-AKT , GFAT, OGT, HSF1, HSF1 phosphorylated in skeletal muscle. The results will be analyzed by ANOVA and Tukey's test (using p d 0.05). (AU)