Project description:Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of liver disease affecting 20-30% of the population in developed countries. NAFLD is strongly associated with abdominal obesity and is recognized as the hepatic manifestation of the metabolic syndrome. In a subgroup of patients with NAFLD inflammation and fibrosis develops, this so-called Non-Alcoholic Steatohepatitis (NASH) may progress to cirrhosis and hepatocellular carcinoma. A multi-hit hypothesis has been proposed in which during the first “hit” fat accumulation occurs in hepatocytes from excessive delivery of fatty acids from adipose tissue, in addition there is an imbalance in lipid synthesis and export. However, the reason why fat accumulation is subsequently followed by inflammation and fibrosis in some patients is poorly understood. We studied the role of inflammatory processes in visceral and subcutaneous fat at the transcriptional level using microarray in bariatric patients from whom the liver histology was available. Patients scheduled for bariatric surgery were recruited in two centers (Pretoria/South-Africa and Antwerpen/Belgium). At the time of the procedure, tissue samples of the visceral and subcutaneous fat were taken for molecular analysis as well as liver tissue for histology, also full biochemical data was collected. Patients were grouped according histology: group I (<5% steatosis), group II (NAFLD, 30-50% steatosis), group III (NASH) and group IV (NASH + fibrosis F2-F3). The following samples were used for microarray (number of 'patients' respectively for stages I-II-III-IV): visceral fat (9-7-7-5), subcutaneous fat (6-6-6-5). Microarrays were run in two batches (15xxx versus 17xxx CEL file samples; indicated in the description field). Samples from two patients (FN61; FN76) were put twice on array (15078+17881; 15064+17877) to verify and exclude batch effects. Please note that, due to technical repeats with two patient samples, the number of 'visceral fat samples' for stages I-II-III-IV is 10-7-8-5.
Project description:Affymetrix miRNA 3.0 array profiling of adipocyte-derived exosomes from obese and lean human subjects We used miRNA arrays to profile exosomes shed from obese and lean human visceral and subcutaneous fat that was cultured for 60 minutes. Human obese and lean visceral and subcutaneous fat were surgically acquired, dissected, and promptly cultured for 60 minutes. We used the culture supernatants for exosome purification and isolation using ExoQuick-TC Precipitation Solution
Project description:We profiled gene expression in peripheral blood cells from 17 obese patients by microarray analysis and revealed that visceral fat adiposity impact on gene expression profile in peripheral blood cells compared to subcutaneous fat accumulation.
Project description:Case story. A patient with massive infiltration of the visceral adipose tissue depot by BAT in a patient with a catecholamine secreting paraganglioma. BAT tissue was identified by protein expression of UCP1 (western blotting and immunostaining) The goal of the study is to identify patterns of gene expression in BAT containing visceral fat compared to the patient's own subcutanous fat which did not express BAT. For comparison a pool of mRNA isolated from visceral fat from obese subjects was used. Patient Case, Gene expression array from a biopsy from the patient's visceral fat and a biopsy from the subcutaneous fat compared to one array of mRNA from the visceral depot pooled from a group of obese subjects
Project description:Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of liver disease affecting 20-30% of the population in developed countries. NAFLD is strongly associated with abdominal obesity and is recognized as the hepatic manifestation of the metabolic syndrome. In a subgroup of patients with NAFLD inflammation and fibrosis develops, this so-called Non-Alcoholic Steatohepatitis (NASH) may progress to cirrhosis and hepatocellular carcinoma. A multi-hit hypothesis has been proposed in which during the first “hit” fat accumulation occurs in hepatocytes from excessive delivery of fatty acids from adipose tissue, in addition there is an imbalance in lipid synthesis and export. However, the reason why fat accumulation is subsequently followed by inflammation and fibrosis in some patients is poorly understood. We studied the role of gene expression at the transcriptional level using microarray in bariatric patients from whom the liver histology was available. Patients scheduled for bariatric surgery were recruited in Pretoria/South-Africa. At the time of the procedure, tissue samples of the visceral and subcutaneous fat were taken for molecular analysis as well as liver tissue for histology, also full biochemical data was collected. Patients were grouped according histology: group I (<5% steatosis), group II (NAFLD, 30-50% steatosis) and group III (NASH). The 15 samples were used for microarray (nr patients respectively for stages I-II-III: 6-4-5).This dataset is part of the TransQST collection.
Project description:Context: It is not known whether biological differences reported between subcutaneous (SAT) and visceral (VAT) adipose tissue depots underlie the pathogenicity of visceral fat. Objective: We compared SAT and VAT gene expression according to obesity, visceral fat accumulation, insulin resistance and presence of the metabolic syndrome. Design: Subjects were assigned into 4 groups (lean, overweight, obese and obese with metabolic syndrome). Setting: Subjects were recruited at a university hospital. Patients: 32 women were included. Main Outcome Measures: Anthropometric measurements, euglycemic hyperinsulinemic clamps, blood analyses and computed tomography scans were performed and paired samples of SAT and VAT were obtained for DNA microarray-based gene expression profiling.
Project description:This experiment captures the DNA methylation in obese patients with type 2 diabetes in relevant tissues from the disease: liver, subcutaneous and visceral adipose tissues, and whole blood. Samples were obtained during bariatric surgery and preserved in RNAlater at -70 C in RNAlater, until the nucleic acid extraction.
Project description:It has been found that fat oxidation is reduced in the skeletal muscle of obese humans. This study aims to identify the mRNA of proteins involved in fat oxidation that may be reduced in obese and morbidly obese individuals. Information gathered will help in understanding how obesity contributes to cardiovascular disease via insulin resistance. Samples were obtained from patients undergoing elective abdominal surgery.