Project description:This data set consists of a time series of DNA methylation profiles of differentiating human adipocytes in vitro a for different fructose concentration
Project description:BackgroundIncreased adipogenesis and altered adipocyte function contribute to the development of obesity and associated comorbidities. Fructose modified adipocyte metabolism compared to glucose, but the regulatory mechanisms and consequences for obesity are unknown. Genome-wide methylation and global transcriptomics in SGBS pre-adipocytes exposed to 0, 2.5, 5, and 10 mM fructose, added to a 5-mM glucose-containing medium, were analyzed at 0, 24, 48, 96, 192, and 384 h following the induction of adipogenesis.ResultsTime-dependent changes in DNA methylation compared to baseline (0 h) occurred during the final maturation of adipocytes, between 192 and 384 h. Larger percentages (0.1% at 192 h, 3.2% at 384 h) of differentially methylated regions (DMRs) were found in adipocytes differentiated in the glucose-containing control media compared to adipocytes differentiated in fructose-supplemented media (0.0006% for 10 mM, 0.001% for 5 mM, and 0.005% for 2.5 mM at 384 h). A total of 1437 DMRs were identified in 5237 differentially expressed genes at 384 h post-induction in glucose-containing (5 mM) control media. The majority of them inversely correlated with the gene expression, but 666 regions were positively correlated to the gene expression.ConclusionsOur studies demonstrate that DNA methylation regulates or marks the transformation of morphologically differentiating adipocytes (seen at 192 h), to the more mature and metabolically robust adipocytes (as seen at 384 h) in a genome-wide manner. Lower (2.5 mM) concentrations of fructose have the most robust effects on methylation compared to higher concentrations (5 and 10 mM), suggesting that fructose may be playing a signaling/regulatory role at lower concentrations of fructose and as a substrate at higher concentrations.
Project description:Background: An increasing body of evidence has linked fructose intake to colorectal cancer (CRC). African Americans (AAs) consume greater quantities of fructose and are more likely to develop right-side colon cancer than European Americans. Objective: We examined the hypothesis that fructose consumption leads to genomic differences associated with CRC tumor biology. Methods: DNA methylation data from this study was obtained using the Illumina Infinium MethylationEPIC kit (GSE151732). Right and left colon differentially methylated regions (DMRs) were identified using DMRcate through analysis of fructose consumption in normal AA colon biopsies (n=79) undergoing screening colonoscopy. Secondary analysis of CRC tumors was carried out using data derived from TCGA-COAD, GSE101764 and GSE193535. Right colon organoids derived from AA normal colon tissues were exposed to 4.4mM of fructose for 72 hours. Fructose-associated differentially expressed genes (DEGs) were identified using DESeq2. This package was also used to identify DEGs in CRC tumors from TCGA-COAD. Results: We identified 4,263 right colon fructose-associated DMRs (FDR<0.05). In contrast, only 24 DMRs survived multiple testing corrections (FDR<0.05) in matched, left colon. Almost 50% of right colon fructose-associated DMRs overlapped regions implicated in CRC in at least one of three datasets. A highly significant enrichment was also observed between genes corresponding to right colon fructose-associated DMRs and DEGs associated with fructose exposure in AA right colon organoids (P=3.28E-30). Further, overlapping and significant enrichments for a number of fatty acid metabolism, glycolysis and cell proliferation pathways were also found. By further examining the overlap of genes within these pathways that were also differentially expressed in TCGA-COAD, our analysis reveals potential role for PFKP and ANKRD23 in fructose-mediated CRC risk. Conclusions: Our data support that dietary fructose exerts a greater CRC risk-related effect in right than left colon among AAs, alluding to its potential role in contributing to racial disparities in CRC.
Project description:Background/Objectives: Obese subjects have increased number of enlarged fat cells which are reduced in size but not number in post-obesity. We performed DNA methylation profiling in fat cells with the aim of identifying differentially methylated DNA sites (DMS) linked to adipose hyperplasia (many small fat cells) in post-obesity. Subjects/Methods: Genome-wide DNA methylation was analyzed in abdominal subcutaneous fat cells from 16 women examined two years after gastric bypass surgery at a post-obese state (BMI 26±2 kg/m2, mean±s.d.) and 14 never-obese women (BMI 25±2 kg/m2). Gene expression was analyzed in subcutaneous adipose tissue from 9 women in each group. In a secondary analysis, we examined DNA methylation and expression of adipogenesis genes in 15 and 11 obese women, respectively. Results: The average degree of DNA methylation of all analyzed CpG-sites was lower in fat cells from post-obese as compared to never-obese women (P=0.014). 8,504 CpG sites were differentially methylated in fat cells from post-obese versus never-obese women (false discovery rate 1%). DMS were under-represented in CpG-islands and surrounding shores. The 8,504 DMS mapped to 3,717 unique genes; these genes were over-represented in cell differentiation pathways. Notably, 27% of genes linked to adipogenesis (i.e. 35 of 130) displayed DMS (adjusted P=10−8) in post-obese versus never-obese women. Next, we explored DNA methylation and expression of genes linked to adipogenesis in more detail in adipose tissue samples. DMS annotated to adipogenesis genes were not accompanied by differential gene expression in post-obese compared to never-obese women. In contrast, adipogenesis genes displayed differential DNA methylation accompanied by altered expression in obese women, Conclusions: Global CpG hypomethylation and overrepresentation of DMS in adipogenesis genes in fat cells may contribute to adipose hyperplasia in post-obese women. Post obese=16, Control group=14.
Project description:Background/Objectives: Obese subjects have increased number of enlarged fat cells which are reduced in size but not number in post-obesity. We performed DNA methylation profiling in fat cells with the aim of identifying differentially methylated DNA sites (DMS) linked to adipose hyperplasia (many small fat cells) in post-obesity. Subjects/Methods: Genome-wide DNA methylation was analyzed in abdominal subcutaneous fat cells from 16 women examined two years after gastric bypass surgery at a post-obese state (BMI 26±2 kg/m2, mean±s.d.) and 14 never-obese women (BMI 25±2 kg/m2). Gene expression was analyzed in subcutaneous adipose tissue from 9 women in each group. In a secondary analysis, we examined DNA methylation and expression of adipogenesis genes in 15 and 11 obese women, respectively. Results: The average degree of DNA methylation of all analyzed CpG-sites was lower in fat cells from post-obese as compared to never-obese women (P=0.014). 8,504 CpG sites were differentially methylated in fat cells from post-obese versus never-obese women (false discovery rate 1%). DMS were under-represented in CpG-islands and surrounding shores. The 8,504 DMS mapped to 3,717 unique genes; these genes were over-represented in cell differentiation pathways. Notably, 27% of genes linked to adipogenesis (i.e. 35 of 130) displayed DMS (adjusted P=10−8) in post-obese versus never-obese women. Next, we explored DNA methylation and expression of genes linked to adipogenesis in more detail in adipose tissue samples. DMS annotated to adipogenesis genes were not accompanied by differential gene expression in post-obese compared to never-obese women. In contrast, adipogenesis genes displayed differential DNA methylation accompanied by altered expression in obese women, Conclusions: Global CpG hypomethylation and overrepresentation of DMS in adipogenesis genes in fat cells may contribute to adipose hyperplasia in post-obese women.
Project description:The obesity epidemic is developing into the most costly health problem facing the world. Obesity, characterized by excessive adipogenesis and enlarged adipocytes, promotes morbidities, such as diabetes, cardiovascular disease, and cancer. Regulation of adipogenesis is critical to our understanding of how fat cell formation causes obesity and associated health problems. Thy1 (also called CD90), a widely used stem cell marker, blocks adipogenesis and reduces lipid accumulation. Thy1-knockout mice are prone to diet-induced obesity. Although the importance of Thy1 in adipogenesis and obesity is now evident, how its expression is regulated is not. We hypothesized that DNA methylation has a role in promoting adipogenesis and affects Thy1 expression. Using the methylation inhibitor 5-aza-2'-deoxycytidine (5-aza-dC), we investigated whether DNA methylation alters Thy1 expression during adipogenesis in both mouse 3T3-L1 preadipocytes and mouse mesenchymal stem cells. Thy1 protein and mRNA levels were decreased dramatically during adipogenesis. However, 5-aza-dC treatment prevented that phenomenon. Methylation-sensitive pyrosequencing analysis showed that CpG sites at the Thy1 locus have increased methylation during adipogenesis, as well as increased methylation in adipose tissue from diet-induced obese mice. These new findings highlight the potential role of Thy1 and DNA methylation in adipogenesis and obesity.-Flores, E. M., Woeller, C. F., Falsetta, M. L., Susiarjo, M., Phipps, R. P. Thy1 (CD90) expression is regulated by DNA methylation during adipogenesis.
Project description:This SuperSeries is composed of the following subset Series: GSE22866: DNA Methylation Profiling of Glioblastoma: Impact on Gene Expression and Clinical Outcome (Agilent Expression Study) GSE22867: DNA Methylation Profiling of Glioblastoma: Impact on Gene Expression and Clinical Outcome (Illumina) Refer to individual Series
Project description:To investigate the beneficial effects of DHA (omega-3) on affecting fructose induced brain dysfunction and metabolic disorders by sequencing the methylome (RRBS) in the hypothalamus and hippocampus of male SD rats.