Metabolomics analyses on stored human RBCs from two cohorts of patients who received testosterone replacement therapy (TRT) and their matched controls (no TRT). A, Top significant metabolites by ANOVA and related pathways are highlighted in the heat map for cohort 1, which consisted of five TRT patients who presented for therapeutic phlebotomy and three sex, age, and race/ethnicity-matched controls. B, Top significant metabolites by ANOVA and related pathways are highlighted in the heat map for cohort 2, which consisted of six eligible allogeneic blood donors (n = 3 TRT and n = 3 matched controls)