Adiponectin is an adipokine increasing glucose and fatty acid metabolism and improving insulin sensitivity. The aim of this study was to investigate the role of adiponectin in the regulation of adipocyte lipolysis. Human adipocytes isolated from biopsies obtained during surgical operations from 16 non-obese and 17 obese subjects were incubated with 1) human adiponectin (20 μg/ml) or 2) 0.5 mM AICAR - activator of AMPK (adenosine monophosphate activated protein kinase). Following these incubations, isoprenaline was added (10-6 M) to investigate the influence of adiponectin and AICAR on catecholamine-induced lipolysis. Glycerol concentration was measured as lipolysis marker. We observed that adiponectin suppressed spontaneous lipolysis by 21 % and isoprenaline-induced lipolysis by 14 % in non-obese subjects. These effects were not detectable in obese individuals, but statistically significant differences in the effect of adiponectin between ob ese and non-obese were not revealed by two way ANOVA test. The inhibitory effect of AICAR and adiponectin on lipolysis was reversed by Compound C. Our results suggest, that adiponectin in physiological concentrations inhibits spontaneous as well as catecholamine-induced lipolysis. This effect might be lower in obese individuals and this regulation seems to involve AMPK., Z. Wedellová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Accumulation of adipose tissue in lower body lowers risk of cardiovascular and metabolic disorders. The molecular basis of this protective effect of gluteofemoral depot is not clear. The aim of this study was to compare the profile of expression of inflammation-related genes in su bcutaneous gluteal (sGAT) and abdominal (sAAT) adipose tissue at baseline and in response to multiphase weight-reducing dietary intervention (DI). 14 premenopausal healthy obese women underwent a 6 months’ DI consisting of 1 month very-low-calorie-diet (VLCD), subsequent 2 months’ low-calori e-diet and 3 months’ weight maintenance diet (WM). Paired samples of sGAT and sAAT were obtained before and at the end of VLCD and WM periods. mRNA expression of 17 genes (macrophage markers, cytokines) was measured using RT-qPCR on chip-platform. At baseline, there were no differences in gene expression of macrophage markers and cytokines between sGAT and sAAT. The dynamic changes induced by DI were similar in both depots for all genes except for three cytokines (IL6, IL10, CCL2) that differed in their response during weight maintenance phase. The results show that, in obese women, there are no major differences between sGAT and sAAT in expression of inflammation-related genes at baseline conditions and in response to the weight-reducing DI., L. Mališová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Retinol binding protein 4 (RBP4) is a novel adipokine which might be involved in the development of insulin resistance. The aim of the study was to investigate the expression of RBP4 mRNA in subcutaneous and visceral fat depots and the relationship between RBP4 plasma and mRNA levels relative to indices of adiposity and insulin resistance. In 59 Caucasian women (BMI 20 to 49 kg/m2 ) paired samples of subcutaneous and visceral fat were obtained for RBP4, leptin and GLUT 4 mRNA analysis using reverse transcription-quantitative PCR. Euglycemic hyperinsulinemic clamp and computed tomography scans were performed. RBP4 mRNA levels as well as GLUT 4 mRNA and leptin mRNA levels were lower (P<0.001, P<0.01 and P<0.001, respectively) in visceral compared to subcutaneous fat. No differences were found in RBP4 mRNA expression in the two fat depots or in RBP4 plasma levels between subgroups of non-obese subjects (n=26), obese subjects without metabolic syndrome (n=17) and with metabolic syndrome (n=16). No correlations between RBP4 mRNA or plasma levels relative to adiposity, glucose disposal rate and GLUT 4 mRNA expression in adipose tissue were found. There was a weak positive correlation between plasma RBP4 and plasma triglycerides (r = 0.30, p<0.05) and between plasma RBP4 and blood glucose (r = 0.26, p<0.05). Regardless of the state of adiposity or insulin resistance, RBP4 expression in humans was lower in visceral than in subcutaneous fat. We found no direct relationship between either RBP4 mRNA or its plasma levels and the adiposity or insulin resistance. and Obsahuje bibliografii a bibliografické odkazy