Targeted Metabolomics Reveals Plasma Biomarkers and Metabolic Alterations of the Aging Process in Healthy Young and Older Adults

With the exponential rise in the older population for the coming years, many studies have aimed to further investigate potential solutions to the aging process. It has been well understood that age is the largest risk factor for chronic disease due to younger individuals possessing more prevalent and adaptive metabolic networks that result in overall health and homeostasis. During the lifecycle, several physiological alterations ensue throughout the metabolic system that attribute to functional decline. In this cross-sectional analysis, a targeted metabolomic approach was applied to investigate the plasma metabolome of 151 young (n = 75) and older adults (n = 76). A corrected MANOVA model was generated, with such covariates as gender, BMI, and chronic condition score (CCS), to analyze the aging process of the two populations. Metabolites associated with impaired fatty acid metabolism were found to be most significant: palmitic acid (p < 0.001), 3-hexenedioic acid (p < 0.001), stearic acid (p = 0.005), and decanoylcarnitine (p = 0.036). Derivatives of amino acid metabolism, 1-methlyhistidine (p = 0.035) and methylhistamine (p = 0.027), were found to be increased in the younger population and several novel metabolites were identified, such as cadaverine (p = 0.034), 4-ethylbenzoic acid (p = 0.029), and 3-hexenedioic acid (p < 0.001). Principal component analysis was conducted and highlighted a shift in the metabolome for both groups. Pathway and enrichment analyses uncovered several impacted pathways that elucidate the metabolic alterations in the older population and aid in further explanation of the aging process. As a result, we offer a better understanding of the aging metabolome and potentially reveal new biomarkers for future study. © FASEB.