Adipose Tissue Expression of the Glycerol Channel Aquaporin-7 Gene Is Altered in Severe Obesity But Not in Type 2 Diabetes

Context: Aquaporin-7 is required for efflux of glycerol from adipocytes and influences whole-body glucose homeostasis in animal studies. Objective: Our objective was to test the hypothesis that AQP7 gene expression levels may be affected by presence of obesity and type 2 diabetes in humans. Design: The obesity study cohort consisted of 12 lean, 22 nonseverely obese,and13severelyobesesubjects.Thetype2diabetesstudycohort consisted of 17 lean and 39 obese type 2 diabetic patients. Circulating levels of plasma soluble proteins monocyte chemoattractant protein-1, TNF receptors 1 and 2, and IL-6 and glycerol were measured. The sc adipose tissue gene expression of AQP7, MCP-1, IL-6, TNF, PPAR, and SREBP1c genes was measured by real-time PCR. AQP7 gene mutation analysis was performed.