Regional variation in the secretory function of visceral fat depots from severely obese women (688.4)

Abstract

Because of its hepatic venous drainage, visceral fat accumulation is an important risk factor for obesity‐related metabolic complications. Objective: To examine the secretory function of a properitoneal fat, the round ligament (RL) in severely obese women. Methods: Metabolic biomarkers, adipogenic, pro‐ vs. anti‐inflammatory, and prothrombotic characteristics were assessed in the RL adipose tissue (AT), and compared to visceral depots, the omental (OME) and mesenteric (MES) fat, in forty‐eight severely obese women (BMI, 54 ± 11 kg/m2), aged 38 ± 9 yrs. Expression of key enzymes involved in lipid metabolism (lipoprotein lipase, LPL; hormone‐sensitive lipase, HSL and phosphodiesterase‐3B, PDE‐3B), and of adipogenic factors (peroxisome proliferator activated receptors‐γ1/2, PPAR‐γ1/2) was measured by real‐time PCR. AT mRNA levels of plasminogen activator inhibitor‐1 (PAI‐1), interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α) and adiponectin were also determined. Results: AT‐LPL mRNA levels were the highest in the RL depot (0.005<p<0.05), whereas HSL expression did not show regional variation. The highest PDE‐3B and lowest PAI‐1 mRNA levels were observed in the RL and MES fat (0.0001p<0.05). The lowest IL‐6 and TNF‐α as well as the highest adiponectin and PPAR‐γ1/2 mRNA levels were found in the RL AT (0.0001<p<0.05). Conclusion: Despite its anatomic location in the intraabdominal cavity, RL should not be considered as a “classical” visceral AT, as some of its secretory characteristics may contribute to limit the deleterious impact of visceral fat.Grant Funding Source: Supported by the CIHR and CRIUCPQ