Increased Adipocyte Hypertrophy in Patients with Nascent Metabolic Syndrome

Background and Aims: Metabolic Syndrome (MetS), a global problem, predisposes to an increased risk for Type 2 diabetes and premature cardiovascular disease. While MetS is associated with central obesity, there is scanty data on adipocyte hypertrophy, increased fat cell size (FCS), in MetS. The aim of this study was to investigate FCS status in gluteal adipose tissue biopsy of patients with nascent MetS without the confounding of diabetes, cardiovascular disease, smoking or lipid therapy . Methods and Results: Fasting blood and subcutaneous gluteal adipose tissue (SAT) biopsy were obtained in MetS (n=20) and controls (n=19). Cardio metabolic features, FFA levels, hsCRP and HOMA-IR were significantly increased in patients with MetS. Waist-circumference adjusted-FCS was significantly increased in patients with MetS and increased with increasing severity of MetS. Furthermore, there were significant correlations between FCS with glucose, HDL-C and the ratio of TG: HDL-C. There were significant correlations between FCS and FFA, endotoxin and monocyte TLR4 abundance. Also, FCS correlated with readouts of NLRP3 Inflammasome activity. Most importantly, FCS correlated with markers of fibrosis and angiogenesis. Conclusions: In conclusion, in patients with nascent MetS, we demonstrate WC-adjusted increase in FCS from gluteal AT that correlated with cellular inflammation, fibrosis and angiogenesis. While these preliminary observations were in gluteal fat, future studies are warranted to confirm these findings in visceral and other fat depots.