Duodenojejunal Bypass Plus Sleeve Gastrectomy Reduces Infiltration of Macrophages and Secretion of TNF-α in the Visceral White Adipose Tissue of Goto-Kakizaki Rats.

Abstract

Current studies indicate that inflammation of white adipose tissue (WAT) is a pathogenic characteristic of insulin resistance. However, the significance of visceral WAT inflammation after bariatric surgery remains unclear. Duodenojejunal bypass plus sleeve gastrectomy (DJB-SG) was performed on Goto-Kakisaki rats. Weight, fasting blood glucose (FBG), and homeostatic model assessment of insulin resistance (HOMA-IR) in the DJB-SG group were compared to those in a sham surgery (SHAM) group every 2weeks. The results of an oral glucose tolerance test (OGTT) and the volume of visceral adipose tissue (Visc.Fat) were compared before and 8weeks postsurgery. Eight weeks after surgery, the rats were sacrificed and visceral WAT collected from the greater omentum. Tumor necrosis factor-α (TNF-α) and cluster of differentiation 68 (CD68) expression in the WAT were evaluated in paraffin-embedded sections by immunohistochemistry. Compared with the SHAM group, the DJB-SG group demonstrated a significant reduction in weight, FBG, and HOMA-IR (P < 0.05), with elevation of insulin levels (P < 0.05) from 4weeks after surgery. OGTT and the quantity of Visc.Fat were significantly reduced (P < 0.05) 8weeks after surgery. Moreover, the expression of TNF-α and CD68 in the visceral white adipose tissue was significantly lower 8weeks after surgery (P < 0.05). The DJB-SG model established in Goto-Kakisaki rats achieved anticipated efficacy. Reduced TNF-α-related inflammation in visceral WAT may result in improved insulin resistance.