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 colony-stimulating 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 factors may be key to protecting this subgroup of obese individuals from the adverse metabolic profile associated with excess adiposity.
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 obesepatients 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 colony-stimulating 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 factors may be key to protecting this subgroup of obese individuals from the adverse metabolic profile associated with excess adiposity.
Authors: Nathalie Pamir; Ning-Chun Liu; Angela Irwin; Lev Becker; YuFeng Peng; Graziella E Ronsein; Karin E Bornfeldt; Jeremy S Duffield; Jay W Heinecke Journal: J Biol Chem Date: 2015-04-30 Impact factor: 5.157
Authors: Helen M Lawler; Chantal M Underkofler; Philip A Kern; Christopher Erickson; Brooke Bredbeck; Neda Rasouli Journal: J Clin Endocrinol Metab Date: 2016-02-12 Impact factor: 5.958
Authors: Maeve A McArdle; Orla M Finucane; Ruth M Connaughton; Aoibheann M McMorrow; Helen M Roche Journal: Front Endocrinol (Lausanne) Date: 2013-05-10 Impact factor: 5.555