Omentin is a novel adipokine with insulin-sensitizing effects expressed predominantly in visceral fat. We investigated serum omentin levels and its mRNA expression in subcutaneous adipose tissue (SCAT) of 11 women with type 2 diabetes mellitus (T2DM), 37 obese non-diabetic women (OB) and 26 healthy lean women (C) before and after various weight loss interventions: 2-week very-low-calorie diet (VLCD), 3-month regular exercise and laparoscopic sleeve gastrectomy (LSG). At baseline, both T2DM and OB groups had decreased serum omentin concentrations compared with C group while omen tin mRNA expression in SCAT did not significantly differ among the groups. Neither VLCD nor exercise significantly affected serum omentin concentrations and its mRNA expression in SCAT of OB or T2DM group. LSG significantly increased serum omen tin levels in OB group. In contrast, omentin mRNA expression in SCAT was significantly reduced after LSG. Baseline fasting serum omentin levels in a combined group of the studied subjects (C, OB, T2DM) negatively correlated with BMI, CRP, insulin, LDL-cholesterol, triglycerides and leptin and we re positively related to HDL- cholesterol. Reduced circulating omentin levels could play a role in the etiopathogenesis of obesity and T2DM. The increase in circulating omentin levels and the decrease in omentin mRNA expression in SCAT of obese women after LSG might contribute to surgery-induced metabolic improvements and sustained reduction of body weight., M. Urbanová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Mitochondrial dysfunction is a potentially important player in the development of insulin resistance and type 2 diabetes mellitus (T2DM). We investigated the changes of mRNA expression of genes encoding main enzymatic complexes of mitochondrial respiratory chain in subcutaneous adipose tissue (SCAT) and peripheral monocytes (PM) of 11 subjects with simple obesity (OB), 16 obese patients with T2DM and 17 healthy lean subjects (C) before and after very low-calorie diet (VLCD) using quantitative real time PCR. At baseline in SCAT, both T2DM and OB group had decreased mRNA expression of all investigated mitochondrial genes with the exception of 2 complex I (NDUFA 12) and complex IV (COX 4/1) enzymes in OB subjects. In contrast, in PM only the expression of complex I enzymes NDUFA 12 and MT-ND5 was reduced in both T2DM and
OB subjects along with decreased expression of citrate synthase (CS) in T2DM group. Additionally, T2DM subjects showed reduced activity of pyruvate dehydrogenase and complex IV in peripheral blood elements. VLCD further decreased mRNA expression of CS and complex I (NT-ND5) and II (SDHA) enzymes in SCAT and complex IV (COX4/1) and ATP synthase in PM of T2DM group, while increasing the activity of complex IV in their peripheral blood elements. We conclude that impaired mitochondrial biogenesis and decreased activity of respiratory chain enzymatic complexes was present in SCAT and PM of obese and diabetic patients. VLCD improved metabolic parameters and ameliorated mitochondrial oxidative function in peripheral blood elements of T2DM subjects but had only minor and inconsistent effect on mitochondrial gene mRNA expression in SCAT and PM.