Differential expression of miRNAs related to angiogenesis and adipogenesis in subcutaneous fat of obese and nonobese women.

To disclose the mechanisms surrounding obesity, we selected microRNAs (miRNAs) that target genes involved in adipogenesis, angiogenesis, and inflammation and compared their expression levels in the subcutaneous adipose tissue of 40 obese and nonobese women. Mature miRNAs were extracted from subcutaneous adipose tissue samples that were collected during surgery and quantified by real-time polymerase chain reaction. miR-16 was overexpressed in the nonobese group (n-expression ratio = - 151.1; P < 0.001). Furthermore, the expression levels of two other miRNAs were significantly correlated with waist circumference in nonobese women (miR-27b, r = 0.453; P = 0.027 and miR-424-5p, r = 0.502, P = 0.014). Central and total subcutaneous adipose tissue thicknesses were correlated with miR-424-5p levels (r = 0.506, P = 0.034 and r = 0.475, P = 0.046, respectively) in the nonobese group. In the obese group, miR-424-5p expression was correlated with body mass index (r = 0.582, P = 0.018). miR-16 and miR-424 have shown correlations with body-fat-mass-related parameters. Because these miRNAs have vascular endothelial growth factor (VEGF) and its receptors as target genes, they may be involved in the alterations of angiogenesis observed in obesity. In addition, higher levels of miR-27 and miR-424 were correlated with higher fat depot measurements in nonobese women. These results highlight the importance of miRNA expression in subcutaneous adipose tissue and encourage further investigation of miRNAs as prognostic markers.

Nonalcoholic fatty liver disease in patients with different baseline glucose status undergoing bariatric surgery: analysis of intraoperative liver biopsies and literature review.

BACKGROUND: Bariatric surgery has been investigated as a treatment option for obese patients with nonalcoholic fatty liver disease (NAFLD). Because patients with NAFLD and type 2 diabetes show accelerated progression from liver disease to cirrhosis, it has been suggested that surgery could be indicated for patients with lower degrees of obesity and type 2 diabetes. OBJECTIVE: To analyze the degree of tissue damage in liver biopsies obtained from patients undergoing bariatric surgery, correlating histopathologic findings with their baseline glucose status. SETTING: General hospital in the public health system. METHODS: Intraoperative liver biopsies were obtained from 521 obese patients undergoing bariatric surgery. Patients were divided into 3 study groups according to their preoperative glucose levels: 167 (32.05%) type 2 diabetic, 132 (25.33%) prediabetic, and 222 (42.61%) normoglycemic patients. Tissue samples were classified in accordance with Brunt and Clinical Research Network Nonalcoholic Steatohepatis criteria. RESULTS: Prevalence of NAFLD was 95%. Higher rates of hepatic fibrosis were observed in diabetic patients (56.4%) compared with prediabetic (29.2%), and normoglycemic patients (28.6%) (P<.001). Nonalcoholic steatohepatitis was diagnosed in 59.4% of the diabetics, in 49.2% of the prediabetics, and in 36% of the normoglycemic obese (P<.001). Only 1.5% of the diabetics had no histologic hepatic alterations. CONCLUSION: NAFLD is markedly more severe in diabetic patients. Our data suggest that intraoperative liver biopsy should be considered for diabetic patients undergoing bariatric surgery. Early bariatric surgery should be investigated as a means to prevent progression of NAFLD.