Quantification of Insulin Resistance and MOTS-c

Glucose (C311 autoanalyzer, Roche, Mannheim, Germany) and insulin (cobas e11, Roche, Mannheim, Germany) were measured in plasma and the homeostatic model assessment (HOMA) was used to estimate insulin resistance (HOMA2-IR2; The Oxford Centre for Diabetes, Endocrinology and Metabolism, UK) [48 (link)]. As described previously [14 (link)], MOTS-c was extracted from plasma in acetonitrile-hydrochloric acid and measured using an in-house sandwich ELISA developed at the University of Southern California by the laboratory that first described MOTS-c in human and murine plasma. This ELISA has been extensively validated, and peptide blocking experiments have been undertaken to show specificity of the antibody [14 (link)].