Project description:Background. Differential gene expression in adipose tissue during diet-induced weight loss followed by a weight stability period is not well characterized. Markers of these processes may provide a deeper understanding of the underlying mechanisms. Objective. To identify differentially expressed genes in human adipose tissue during weight loss and weight maintenance after weight loss. Design. RNA from subcutaneous abdominal adipose tissue from nine obese subjects was obtained and analyzed at baseline, after weight reduction on a low calorie diet (LCD), and after a period of group therapy in order to maintain weight stability. Results. Subjects lost 18.8 + 5.4% of their body weight during the LCD and maintained this weight during group therapy. Insulin sensitivity (HOMA) improved after weight loss with no further improvement during weight maintenance. Cyclin-dependent kinase inhibitor 2B (CDKN2B) and JAZF zinc finger 1 (JAZF1), associated with type 2 diabetes, were downregulated. We could also confirm the downregulation of candidates for obesity and related traits, such as tenomodulin (TNMD) and matrix metallopeptidase 9 (MMP9), with weight loss. The expression of other candidates, such as cell death-inducing DFFA-like effector A (CIDEA) and stearoyl-CoA desaturase (SCD) were upregulated during weight loss but returned to baseline levels during weight maintenance. Conclusion. Genes in the adipose tissue are differentially expressed during weight loss and weight maintenance after weight loss. Genes that show sustained regulation may be of potential interest as markers of the beneficial effects of weight loss whereas others seem to be primarily involved in the process of weight loss itself. Nine participants were prescribed a low calorie diet (LCD) containing 1200 kcal/day for approximately three months (101 ± 26 days). Following the weight reduction phase the participants attended a six month follow-up period (167 ± 37 days). By protocol design, subjects were eligible to enter the study if they had lost at least 10% of their initial body weight during the LCD-period and maintained this weight (+5%) after group therapy. Subcutaneous adipose tissue samples were obtained at three time-points: (i) at baseline, (ii) after weight reduction when subjects were no longer losing weight, and (iii) after the group therapy weight maintenance phase.
Project description:Background. Differential gene expression in adipose tissue during diet-induced weight loss followed by a weight stability period is not well characterized. Markers of these processes may provide a deeper understanding of the underlying mechanisms. Objective. To identify differentially expressed genes in human adipose tissue during weight loss and weight maintenance after weight loss. Design. RNA from subcutaneous abdominal adipose tissue from nine obese subjects was obtained and analyzed at baseline, after weight reduction on a low calorie diet (LCD), and after a period of group therapy in order to maintain weight stability. Results. Subjects lost 18.8 + 5.4% of their body weight during the LCD and maintained this weight during group therapy. Insulin sensitivity (HOMA) improved after weight loss with no further improvement during weight maintenance. Cyclin-dependent kinase inhibitor 2B (CDKN2B) and JAZF zinc finger 1 (JAZF1), associated with type 2 diabetes, were downregulated. We could also confirm the downregulation of candidates for obesity and related traits, such as tenomodulin (TNMD) and matrix metallopeptidase 9 (MMP9), with weight loss. The expression of other candidates, such as cell death-inducing DFFA-like effector A (CIDEA) and stearoyl-CoA desaturase (SCD) were upregulated during weight loss but returned to baseline levels during weight maintenance. Conclusion. Genes in the adipose tissue are differentially expressed during weight loss and weight maintenance after weight loss. Genes that show sustained regulation may be of potential interest as markers of the beneficial effects of weight loss whereas others seem to be primarily involved in the process of weight loss itself.
Project description:The purpose of this study was to evaluate the effect of progressive weight loss (5, 10, 15% weight loss) on metabolic function such as multi-organ insulin sensitivity and beta-cell function in obese people. We conducted microarray analysis to determine the effect of progressive weight loss on adipose tissue gene expression profile. We examined subcuntaneous adipose tissue samples obtained from 9 obese subjects before (A) and after 5% (B), 10% (C) and 15% (D) weight loss (total 36 samples).
Project description:Objective: This work aimed at identifying and characterizing differences in subcutaneous adipose tissue (SAT) gene expression patterns between subjects succeeding weight control against subjects regaining weight 6 months after a low calorie diet program. Methods: Weight-reduced obese subjects from 8 European countries were randomized into 4 diets differing in protein and glycemic index. In addition to the anthropometric and plasma parameters, SAT biopsies were taken at the beginning (CID2) and the end (CID3) of the weight maintenance intervention. Pan-genomic cDNA microarrays were used to define SAT gene expression profiles at both CID2 and CID3 of 22 subjects succeeding weight maintenance (successful subjects; mean weight change= -2.6 ± 1.2 kg) and 22 subjects regaining weight (unsuccessful subjects; mean weight change= 3.9 ± 1.3 kg) among the 4 dietary arms. Results: Differences in SAT gene expression patterns between successful and unsuccessful groups were mainly due to weight variations rather to differences in diet macronutrient composition. An ANCOVA analysis with total energy intake at CID3 as covariant led us to the definition of 1339 differential genes. Functional analysis of differential genes showed that cellular growth and proliferation, inflammation, cell death, cancer, cellular function and maintenance were the main biological processes involving these differential genes. Overall design: SAT transcriptome was defined at the beginning (CID2) and at the end (CID3) of the dietary intervention program using a common reference design: Cyanine-5 dye was incorporated into all SAT samples, while a reference RNA pool made of the mix of commercial human liver, adipose tissue, and skeletal muscle RNA was labeled with cyanine-3 dye. Samples were hybridized to Agilent 44K whole human genome microarrays. Evolution in gene expression patterns after dietary intervention was tested in terms of the ratio after/before dietary intervention (CID3/CID2) ratio.
Project description:Objective: This work aimed at identifying and characterizing differences in subcutaneous adipose tissue (SAT) gene expression patterns between subjects succeeding weight control against subjects regaining weight 6 months after a low calorie diet program. Methods: Weight-reduced obese subjects from 8 European countries were randomized into 4 diets differing in protein and glycemic index. In addition to the anthropometric and plasma parameters, SAT biopsies were taken at the beginning (CID2) and the end (CID3) of the weight maintenance intervention. Pan-genomic cDNA microarrays were used to define SAT gene expression profiles at both CID2 and CID3 of 22 subjects succeeding weight maintenance (successful subjects; mean weight change= -2.6 ± 1.2 kg) and 22 subjects regaining weight (unsuccessful subjects; mean weight change= 3.9 ± 1.3 kg) among the 4 dietary arms. Results: Differences in SAT gene expression patterns between successful and unsuccessful groups were mainly due to weight variations rather to differences in diet macronutrient composition. An ANCOVA analysis with total energy intake at CID3 as covariant led us to the definition of 1339 differential genes. Functional analysis of differential genes showed that cellular growth and proliferation, inflammation, cell death, cancer, cellular function and maintenance were the main biological processes involving these differential genes.
Project description:Transcriptional profiling of subcutaneous adipose tissue before and after 2 years of bariatric surgery. This type of surgery produce a masive weight loss in morbidly obese subjects, and improve the comorbidities associated to obesity. Goal was to determine the effects of bariatric surgery on the gene expression of subcutaneous adipose tissue.
Project description:The nutritional intervention program “DiOGenes” focuses on how obesity can be prevented and treated from a dietary perspective. We have generated differential plasma proteome profiles in the DiOGenes cohort to identify proteins associated with weight loss and maintenance and explore their relation to body mass index, fat mass, insulin resistance and sensitivity. Relative protein quantification was obtained at baseline and after combined weight loss/maintenance phases using isobaric tagging and MS/MS. 473 subjects were measured at baseline and end of the intervention; 183 proteins were quantified in more than 70% of the plasma samples. The MS-based proteomic analysis of this large cohort of non-diabetic overweight and obese individuals concomitantly identified known and novel proteins associated with weight loss and maintenance. ClinicalTrials.gov Identifier: NCT00390637
Project description:Subcutaneous adipose tissue transcriptomes were compared between 21 obese individuals that either maintained weight loss (good controllers) or regained weight (poor controllers) during a 2-phase dietary Intervention. Dietary intervention: Individuals underwent 8-weeks of calorie-restriction, then 6-months of ad libitum diet.
Project description:We investigated the regulation of adipose tissue (AT) gene expression during different phases of a dietary weight loss program and its relationship with insulin sensitivity. Obese women followed a weight reduction program composed of an energy restriction phase (ER) with a 4-week very-low-calorie diet and a weight stabilization period (WS) composed of a 2-month low-calorie diet followed by 3 to 4 months of a weight maintenance diet. At each time point, body composition, plasma parameters and glucose disposal rate were assessed and subcutaneous AT biopsies were performed. Variations in mRNA levels were determined using DNA microarrays and reverse transcription-quantitative PCR. Distinct sets of AT genes are regulated during calorie restriction and weight stabilization revealing an unexpected temporal pattern in the link between AT and insulin sensitivity during weight loss.