Autophagy in peripheral blood mononuclear cells is associated with body fat percentage

Context: Numerous chronic conditions including obesity exhibit autophagic dysfunction. Association of immune cell autophagic marker regulation by body fat percentage (%BF) is unknown. Objective: Investigate autophagy activity in peripheral blood mononuclear cells (PBMCs) of adults with distinct %BFs and obesity-related circulating inflammatory markers. Materials and methods: Sixteen individuals (eight males) with %BF above (n = 8, 36.9 +/- 3.6 years, 27.1 +/- 8.1%BF) and below (n = 8, 37.1 +/- 3.7 years, 13.3 +/- 3.7%BF) their age- and sex-specific 50th percentile value based on the American College Sports Medicine guidelines participated. Body fat percentage was calculated from hydrostatic weighing. PBMCs were isolated from venous blood, and PBMC autophagic flux markers (LC3-I, LC3-II, and p62) were measured via Western blot. CRP, resistin, leptin, and adiponectin were measured via ELISA. Results: LC3-II/LC3-I ratio correlated with %BF (r=-0.56, p=.023). Insulin (p=.05) and CRP (p=.018) were higher in high %BF participants. Discussion and conclusions: Autophagic activity markers in PBMCs correlate with %BF, but are not different between %BF groups.