Metabolomics in the Context of Exercise in Subjects with Multimorbidity: A Pilot Study

Lifestyle-related diseases, such as overweight/obesity, diabetes mellitus type 2 (T2DM), cardiovascular disease, or osteoarthritis, are a major health burden in Western societies. Due to common risk factors, most patients suffer from multimorbidity, i.e., have been diagnosed with more than one of these diseases. Physical activity (PA) is known to have a positive effect on all of these diseases; however, little is known about the effects of PA on patients with multimorbidity. In particular, so far, no reliable biomarkers have been found to predict and monitor the effects of PA-based lifestyle intervention programs on these subjects. Employing a metabolomics approach with dried blood spots, we analyzed the concentrations of different metabolites in subjects with multimorbidity over the course of the lifestyle intervention program MultiPill-Exercise. We found increased concentrations of all tested amino acids (AAs), total carnitine (Cx), and short- (C2-C6) and long- (>C12) chain acylcarnitines (ACs) after 12 weeks (t1) and/or 24 weeks (t2) of intervention. When correlating baseline (t0) metabolite concentrations with changes in physiological and clinical parameters, we observed associations of various metabolite concentrations with changes in metabolic and cardiovascular parameters. When analyzing metabolite acute reactions in response to exhaustive exercise (ergometer test), however, few overall changes were observed. Nevertheless, a significant negative correlation was found between the mobilization of medium-chain acylcarnitines (MC-ACs) at t2 and changes in peak power output (PPO) between t0 and t2. Taken together, these data suggest that specific AAs and ACs might be candidate biomarkers to predict and monitor the effects of PA-based lifestyle intervention programs in subjects with multimorbidity, a hypothesis that should be further tested in larger cohorts.