O'Connell J.,Obesity and Immunology Research Group |
O'Connell J.,Park University |
Lynch L.,Obesity and Immunology Research Group |
Lynch L.,Education and Research Center |
And 5 more authors.
Journal of Clinical Endocrinology and Metabolism
Context: Dysfunctional adipose tissue has been proposed as a key pathological process linking obesity and metabolic disease. Preadipocyte factor-1 (Pref-1) has been shown to inhibit differentiation in adipocyte precursor cells and could thereby play a role in determining adipocyte size, adipose tissue functioning, and metabolic profile in obese individuals. Objective: We hypothesized that adipose tissue from metabolically healthy obese (MHO) and matched metabolically unhealthy obese individuals would demonstrate distinct differences in relation to Pref-1 expression, adipocyte size, and inflammatory markers. Design, Setting, and Patients: This was a cross-sectional study, investigating obese patients undergoing bariatric surgery at a tertiary referral centre. Patients included 12 MHO and 17 age- and body mass index-matched metabolically unhealthy obese individuals. Main Outcome Measures: Pref-1, monocyte chemotactic protein-1, TNF-α, granulocyte colonystimulating factor, IL-6, and adiponectin levels, macrophage numbers, and adipocyte size were measured in omental and subcutaneous adipose tissue. Results: The MHO group had a lower level of Pref-1 (per 1000 adipocytes) in both subcutaneous [160 (136-177) versus 194 (153-355); P<0.05] and omental adipose tissue [102 (32-175) versus 194 (100-350); P < 0.005]. This was associated with lower numbers of macrophages, lower levels of TNF-α, monocyte chemotactic protein-1, and granulocyte colony-stimulating factor, and higher levels of adiponectin. Omental Pref-1 showed strong correlations with adipocyte size (r=0.67, P< 0.0005) and metabolic and adipokine parameters, including percent fatty liver (r=0.62, P<0.005), fasting glucose (r = 0.68, P < 0.0005), triglyceride (r = 0.60, P < 0.005), high-density lipoprotein cholesterol (r = -0.46, P < 0.05), and adiponectin (r= -0.71, P < 0.05). Conclusion: Adipose tissue in MHO individuals had lower levels of Pref-1, a known inhibitor of preadipocyte differentiation, and a more favorable inflammatory profile. These factorsmaybe key to protecting this subgroup of obese individuals from the adverse metabolic profile associated with excess adiposity. Copyright © 2011 by The Endocrine Society. Source