Mass Spectrometry Quantitation and Analysis of Urinary Metabolites of Grape Seed Extract Polyphenols in a Rat Model of Menopause (1025.11)

Differences in urinary biomolecules following ovariectomy, and the impact of dietary polyphenols (grapeseed extract [GSE]) in rodents were examined by nanoLC‐tandem mass spectrometry, and the impact of dietary polyphenols (grapeseed extract [GSE]). Urines from sham‐ovariectomy (OVX) and ovariectomized ((OVX) rats were analyzed, where both groups were given GSE, thus, any differences were due to the OVX. In positive mode LC‐MS/MS, 5,589 peaks were resolved with unique retention times. Of these, 12% were significantly different in abundance (p<0.05), with 2% of this subgroup (p<0.001). Conclusive identification of significant peaks required both the METLIN software on the Scripps XCMS server (Tautenhahn et al., Anal. Chem, 2012) and the Human Metabolome Database (Wishart et al., Nucleic Acids Res, 2007). Experiments are ongoing to continue identification of peaks using MS/MS, as well as to populate the appropriate databases with conjugated forms of polyphenols to enable deeper analysis. In TARGETED metabolomics analysis, we determined that glucuronidated grapeseed polyphenols were increased in the urines of OVX rats, indicating that OVX increased the amount or activity of the relevant glucuronosyltransferases. This is the first metabolomics analysis of urinary biomolecules in a model of menopause, and of effects and fate of dietary polyphenols.Grant Funding Source: NIH/NCCAM R21‐AT00480531