NMR‐based metabolomics analysis in muscle and serum of middle‐aged ovariectomized rats supplemented with 6‐month green tea polyphenols

Abstract

Metabolomics is an important component of system biology complementing genomics, transcriptomis, and proteomics. The project is to determine the effects of 6-month green tea polyphenols (GTP) supplementation on the serum and muscle metabolome in middle-aged ovariectomized (OVX) rats. 39 SD (6-mo-old) rats were sham-operated (n=13) or OVX (n=26). Both sham and OVX animals received no GTP for 6 months. The remaining OVX animals were provided 1.5% w/v GTP in drinking water for 6 months. Endogenous metabolites in serum and muscle were measured using NMR-based metabolomics. Compared to the sham animals, the OVX animals had the following observation in serum: (1) suppressed glucose metabolites and Krebs cycle (decreases in acetate, acetoacetate, acetone, glycerol, glucose, lactate, pyruvate, citrate, succinate and fumarate), (2) altered amino acids metabolites (decreases in alanine, asparagine, glutamine, isoleucine, leucine, valine, tryptophan, lysine, proline, seruine and threonine; increases in glutamate, glycine, phenylalanine and tyrosine), and (3) reduced lipid metabolites (decreases in myo-inositol). The similar trend in serum of OVX animals was also observed in that of muscle of OVX animals. Intriguingly, compared to the OVX animals, 6-month GTP supplementation to the OVX-treated animals reversed the negative impacts of ovariectomy on the middle-aged rats in terms of metabolites of glucose, Kerbs cycle, amino acids, and lipids. The results suggest that chronic GTP supplementation to the OVX animals affects whole-body metabolism, as shown in serum and muscle. Study supported by NIH/NCCAM AT006691.