High-salt diet affects amino acid metabolism in plasma and muscle of Dahl salt-sensitive rats

Genetic background and high-salt diet are considered key factors contributing to the development of hypertension and its associated metabolic disorders. Metabolomics is an emerging powerful tool to analyze the low-molecular weight metabolites in plasma and tissue. This study integrated metabolomics and correlation network analysis to investigate the metabolic profiles of plasma and muscle of Dahl salt-sensitive (SS) rats and SS.13(BN) rats (control) under normal and high-salt diet. The hub metabolites, which could play important roles in the metabolic changes, were identified by correlation network analysis. The results of the network analysis were further confirmed by pathway analysis and enzyme activity analysis. The results indicated a higher amino acid levels in both plasma and muscle of SS rats fed with high-salt diet. Alanine was found as a hub metabolite with the highest score of three centrality indices and also as the significant differential metabolite in plasma of SS rats after high-salt diet. Valine and lysine were found as hub metabolites and differential metabolites in muscle of SS rats after high-salt diet. Amino acid levels increased in both plasma and muscle of SS rats fed with a high salt diet. Moreover, alanine in plasma and valine and lysine in muscle as hub metabolites could play important roles in the response to high-salt diet.