Adipose tissue retains an epigenetic memory of obesity after weight loss [CUT&TAG]
Ontology highlight
ABSTRACT: Reducing body weight to improve metabolic health and related comorbidities is a primary goal in treating obesity. However, maintaining weight loss is a considerable challenge, especially as the body appears to retain an obesogenic memory that defends against body weight changes. Overcoming this barrier for long-term treatment success is difficult because the molecular mechanisms underpinning this phenomenon remain largely unknown. Here, by using single-nuclei RNA-sequencing, we show that both human and mouse adipose tissue retain cellular transcriptional changes after appreciable weight loss. Furthermore, we find persistent obesity-induced alterations in the mouse adipocyte epigenome, negatively affecting their function and response to metabolic stimuli. Mice carrying this obesogenic memory show accelerated rebound weight gain, and the epigenetic memory can explain future transcriptional deregulation in adipocytes in response to further high-fat diet feeding. In summary, our findings indicate the existence of an obesogenic memory, largely based on stable epigenetic changes, in mouse adipocytes, and likely other cell types. These changes appear to prime cells for pathological responses in an obesogenic environment, contributing to the problematic "yo-yo" effect often seen with dieting. Targeting these changes in the future could improve long-term weight management and health outcomes.
Project description:Reducing body weight to improve metabolic health and related comorbidities is a primary goal in treating obesity. However, maintaining weight loss is a considerable challenge, especially as the body appears to retain an obesogenic memory that defends against body weight changes. Overcoming this barrier for long-term treatment success is difficult because the molecular mechanisms underpinning this phenomenon remain largely unknown. Here, by using single-nuclei RNA-sequencing, we show that both human and mouse adipose tissue retain cellular transcriptional changes after appreciable weight loss. Furthermore, we find persistent obesity-induced alterations in the mouse adipocyte epigenome, negatively affecting their function and response to metabolic stimuli. Mice carrying this obesogenic memory show accelerated rebound weight gain, and the epigenetic memory can explain future transcriptional deregulation in adipocytes in response to further high-fat diet feeding. In summary, our findings indicate the existence of an obesogenic memory, largely based on stable epigenetic changes, in mouse adipocytes, and likely other cell types. These changes appear to prime cells for pathological responses in an obesogenic environment, contributing to the problematic "yo-yo" effect often seen with dieting. Targeting these changes in the future could improve long-term weight management and health outcomes.
Project description:Reducing body weight to improve metabolic health and related comorbidities is a primary goal in treating obesity. However, maintaining weight loss is a considerable challenge, especially as the body appears to retain an obesogenic memory that defends against body weight changes. Overcoming this barrier for long-term treatment success is difficult because the molecular mechanisms underpinning this phenomenon remain largely unknown. Here, by using single-nuclei RNA-sequencing, we show that both human and mouse adipose tissue retain cellular transcriptional changes after appreciable weight loss. Furthermore, we find persistent obesity-induced alterations in the mouse adipocyte epigenome, negatively affecting their function and response to metabolic stimuli. Mice carrying this obesogenic memory show accelerated rebound weight gain, and the epigenetic memory can explain future transcriptional deregulation in adipocytes in response to further high-fat diet feeding. In summary, our findings indicate the existence of an obesogenic memory, largely based on stable epigenetic changes, in mouse adipocytes, and likely other cell types. These changes appear to prime cells for pathological responses in an obesogenic environment, contributing to the problematic "yo-yo" effect often seen with dieting. Targeting these changes in the future could improve long-term weight management and health outcomes.
Project description:Reducing body weight to improve metabolic health and related comorbidities is a primary goal in treating obesity. However, maintaining weight loss is a considerable challenge, especially as the body appears to retain an obesogenic memory that defends against body weight changes. Overcoming this barrier for long-term treatment success is difficult because the molecular mechanisms underpinning this phenomenon remain largely unknown. Here, by using single-nuclei RNA-sequencing, we show that both human and mouse adipose tissue retain cellular transcriptional changes after appreciable weight loss. Furthermore, we find persistent obesity-induced alterations in the mouse adipocyte epigenome, negatively affecting their function and response to metabolic stimuli. Mice carrying this obesogenic memory show accelerated rebound weight gain, and the epigenetic memory can explain future transcriptional deregulation in adipocytes in response to further high-fat diet feeding. In summary, our findings indicate the existence of an obesogenic memory, largely based on stable epigenetic changes, in mouse adipocytes, and likely other cell types. These changes appear to prime cells for pathological responses in an obesogenic environment, contributing to the problematic "yo-yo" effect often seen with dieting. Targeting these changes in the future could improve long-term weight management and health outcomes.
Project description:Dieting is a popular yet often ineffective way to lower body weight, as the majority of people regain most of their pre-dieting weights in a relatively short time. The underlying molecular mechanisms driving weight regain and the increased risk for metabolic disease are still incompletely understood. Here we investigate the molecular alterations inherited from a history of obesity. In our model, male HFD fed obese C57BL/6J mice, were switched to a low caloric chow diet, resulting in a decline of body weight to that of lean mice. Within seven weeks after diet switch, most obesity associated phenotypes, such as body mass, glucose intolerance and blood metabolite levels were reversed. However, hepatic inflammation, hepatic steatosis as well as hypertrophy and inflammation of perigonadal, but not subcutaneous, adipocytes persisted in formerly obese mice. Transcriptional profiling of liver and perigonadal fat revealed an upregulation of pathways associated with immune function and cellularity. Thus, we show that weight reduction leaves signs of inflammation in liver and perigonadal fat, indicating that persisting proinflammatory signals in liver and adipose tissue could contribute to an increased risk of formerly obese subjects to develop the metabolic syndrome upon recurring weight gain.
Project description:Dieting is a popular yet often ineffective way to lower body weight, as the majority of people regain most of their pre-dieting weights in a relatively short time. The underlying molecular mechanisms driving weight regain and the increased risk for metabolic disease are still incompletely understood. Here we investigate the molecular alterations inherited from a history of obesity. In our model, male HFD fed obese C57BL/6J mice, were switched to a low caloric chow diet, resulting in a decline of body weight to that of lean mice. Within seven weeks after diet switch, most obesity associated phenotypes, such as body mass, glucose intolerance and blood metabolite levels were reversed. However, hepatic inflammation, hepatic steatosis as well as hypertrophy and inflammation of perigonadal, but not subcutaneous, adipocytes persisted in formerly obese mice. Transcriptional profiling of liver and perigonadal fat revealed an upregulation of pathways associated with immune function and cellularity. Thus, we show that weight reduction leaves signs of inflammation in liver and perigonadal fat, indicating that persisting proinflammatory signals in liver and adipose tissue could contribute to an increased risk of formerly obese subjects to develop the metabolic syndrome upon recurring weight gain.
Project description:Toll-like receptors/Interleukin-1 receptor (IL-1R) signaling plays an important role in High-fat diet (HFD)-induced adipose tissue dysfunction contributing to obesity-associated metabolic syndromes. Here, we show an unconventional IL-1R-IRAKM (IL-1R-associated kinase M)-Slc25a1 signaling axis in adipocytes that reprograms lipogenesis to promote diet-induced obesity. Adipocyte-specific deficiency of IRAKM reduced HFD-induced body weight gain, increased whole body energy expenditure and improved insulin resistance, associated with decreased lipid accumulation and adipocyte cell sizes. IL-1β stimulation induced the translocation of IRAKM Myddosome to mitochondria to promote de novo lipogenesis in adipocytes. Mechanistically, IRAKM interacts with and phosphorylates mitochondrial citrate carrier Slc25a1 to promote IL-1β-induced mitochondrial citrate transport to cytosol and de novo lipogenesis. Moreover, IRAKM-Slc25a1 axis mediates IL-1β induced Pgc1a acetylation to regulate thermogenic gene expression in adipocytes. IRAKM kinase-inactivation also attenuated HFD-induced obesity. Taken together, our study suggests that the IL-1R-IRAKM-Slc25a1 signaling axis tightly links inflammation and adipocyte metabolism, indicating a novel therapeutic target for obesity.
Project description:We have previously reported that radix Angelica sinensis (RAS) suppressed body weight and altered FTO expression in mice with high fat diet (HFD)-induced obesity. In the present study we performed RNA sequencing-mediated transcriptome analysis to elucidate the molecular mechanisms underlying the anti-obesogenic effects of RAS in mice. The results revealed that 36 differentially-expressed genes (DEGs) were identified between the RAS supplementation group (DH) and control group (HC). These 36 DEGs were clustered into 297 functional gene ontology (GO) categories, among which several GO annotations and signaling pathways were associated with lipid homeostasis. Six out of the 36 DEGs were identified to be involved in lipid metabolism, with the APOA2 gene a potential anti-obesogenic influence. The expression pattern revealed by RNA-Seq was identical to the results of quantitative real-time PCR (qPCR). Therefore, RAS supplementation in HFD-induced obese mice was associated with an anti-obesogenic global transcriptomic response. This study provides insight into potential applications of RAS in obesity therapy.
Project description:Objective Obesity is a multidimensional condition that is treatable by the restoration of a lean phenotype; however, some obesity-related outcomes may persist after weight normalization. Among the organs of the human body, the brain possesses a relatively low regenerative capacity and could retain perturbations established as a result of developmental obesity. Calorie restriction (CR) or a restricted ketogenic diet (KD) are successfully used as weight loss approaches, but their impact on obesity-related effects in the brain have not been previously evaluated. Methods We performed a series of experiments in a rat model of developmental obesity induced by a 12-week cafeteria diet, followed by CR to implement weight loss. First, we assessed the impact of obesity on neurogenesis (BrdU incorporation into the hippocampus), cognitive function (water maze), and concomitant changes in hippocampal protein expression (GC/MS-MS, western blot). Next, we repeated these experiments in a rat model of weight loss induced by CR. We also measured mitochondrial enzyme activity in rats after weight loss during the fed or fasting state. By using a modified version of the water maze we evaluated cognitive abilities in rats subjected to weight loss by CR or a restricted KD. Results In this study, obesity affected metabolic processes, upregulated hippocampal NF-κB, and induced proteomic differences which were associated with impaired cognition and neurogenesis. Weight loss improved neurogenesis and enhanced cognition. While the expression pattern of some proteins persisted after weight loss, most of the changes appeared de novo revealing metabolic adjustment by overactivation of citrate synthase and downregulation of ATP synthase. As a consequence of fasting, the activity of these enzymes indicated hippocampal adaptation to negative energy balance during the weight loss phase of CR. Moreover, the effects on cognitive abilities measured after weight loss were negatively correlated with the obesity level and were alleviated by KD, which improved cognition when used as a weight loss approach. Conclusions The study shows that cognition and mitochondrial metabolism in the hippocampus are affected by CR- or KD-induced weight loss.
Project description:Obesity has been linked to lifestyle and recently have been associated to DNA methylation changes that may cause alterations in the adipogenesis and lipid storage processes and contribute to the pathological state. We enrolled Obese (Ob) and Normal Weight (NW) women. We observed that DNA methylation patterns are different between normal weight and obese women. This can alter gene expression patterns affecting adipogenesis and lipid storage. This results confirms that an obesogenic lifestyle can promote epigenetic changes in the human DNA.
Project description:High-fat diet (HFD)-induced obesity is a multi-factorial disease including genetic, physiological, behavioral, and environmental components. Drosophila has emerged as an effective metabolic disease model. Cytidine 5'-triphosphate synthase (CTPS) is a crucial enzyme for the de novo synthesis of CTP, governing the cellular level of CTP and phospholipid synthesis. CTPS has been found to form filaments known as cytoophidia, which are evolutionarily conserved in bacteria, archaea, and eukaryotes. Here, we show that CTPS functions in fat bodies to regulate body weight and starvation resistance in Drosophila. HFD-induced obesity enhances CTPS transcription and lengthens cytoophidia in larval adipocytes. CTPS depletion in the fat body prevented HFD-induced obesity, including body weight gain, adipocyte expansion, and lipid accumulation, by inhibiting the PI3K-Akt-SREBP axis. A dominant-negative form of CTPS also inhibits adipocyte expansion and down-regulates lipogenic genes. As a result, our findings not only establish a functional link between CTPS and lipid homeostasis but also highlight a potential role of CTPS manipulation in the treatment of HFD-induced obesity.