DSpace Collection:
https://hdl.handle.net/10171/22563
2024-03-28T09:39:35ZA dual epigenomic approach for the search of obesity biomarkers: DNA methylation in relation to diet-induced weight loss
https://hdl.handle.net/10171/28316
Title: A dual epigenomic approach for the search of obesity biomarkers: DNA methylation in relation to diet-induced weight loss
Abstract: Epigenetics could help to explain individual differences in weight loss after an energy-restriction intervention. Here, we identify novel potential epigenetic biomarkers of weight loss, comparing DNA methylation patterns of high and low responders to a hypocaloric diet. Twenty-five overweight or obese men participated in an 8-wk caloric restriction intervention. DNA was isolated from peripheral blood mononuclear cells and treated with bisulfite. The basal and endpoint epigenetic differences between high and low responders were analyzed by methylation microarray, which was also useful in comparing epigenetic changes due to the nutrition intervention. Subsequently, MALDI-TOF mass spectrometry was used to validate several relevant CpGs and the surrounding regions. DNA methylation levels in several CpGs located in the ATP10A and CD44 genes showed statistical baseline differences depending on the weight-loss outcome. At the treatment endpoint, DNA methylation levels of several CpGs on the WT1 promoter were statistically more methylated in the high than in the low responders. Finally, different CpG sites from WT1 and ATP10A were significantly modified as a result of the intervention. In summary, hypocaloric-diet-induced weight loss in humans could alter DNA methylation status of specific genes. Moreover, baseline DNA methylation patterns may be used as epigenetic markers that could help to predict weight loss.2011-01-01T00:00:00ZCLOCK, PER2 and BMAL1 DNA methylation: association with obesity and metabolic syndrome characteristics and monounsaturated fat intake
https://hdl.handle.net/10171/28108
Title: CLOCK, PER2 and BMAL1 DNA methylation: association with obesity and metabolic syndrome characteristics and monounsaturated fat intake
Abstract: The circadian clock system instructs 24-h rhythmicity on gene expression in essentially all cells, including adipocytes, and epigenetic mechanisms may participate in this regulation. The aim of this research was to investigate the influence of obesity and metabolic syndrome (MetS) features in clock gene methylation and the involvement of these epigenetic modifications in the outcomes. Sixty normal-weight, overweight and obese women followed a 16-weeks weight reduction program. DNA methylation levels at different CpG sites of CLOCK, BMAL1 and PER2 genes were analyzed by Sequenom's MassARRAY in white blood cells obtained before the treatment. Statistical differences between normal-weight and overweight + obese subjects were found in the methylation status of different CpG sites of CLOCK (CpGs 1, 5-6, 8 and 11-14) and, with lower statistical significance, in BMAL1 (CpGs 6-7, 8, 15 and 16-17). The methylation pattern of different CpG sites of the three genes showed significant associations with anthropometric parameters such as body mass index and adiposity, and with a MetS score. Moreover, the baseline methylation levels of CLOCK CpG 1 and PER2 CpGs 2-3 and 25 correlated with the magnitude of weight loss. Interestingly, the percentage of methylation of CLOCK CpGs 1 and 8 showed associations with the intake of monounsaturated and polyunsaturated fatty acids. This study demonstrates for the first time an association between methylation status of CpG sites located in clock genes (CLOCK, BMAL1 and PER2) with obesity, MetS and weight loss. Moreover, the methylation status of different CpG sites in CLOCK and PER2 could be used as biomarkers of weight-loss success, particularly CLOCK CPGs 5-6.2012-01-01T00:00:00ZDietary factors, epigenetic modifications and obesity outcomes: Progresses and perspectives
https://hdl.handle.net/10171/28106
Title: Dietary factors, epigenetic modifications and obesity outcomes: Progresses and perspectives
Abstract: Nutritional factors play a life-long role in human health. Indeed, there is growing evidence that one of the mechanisms by which nutrients and bioactive compounds affect metabolic traits is epigenetics. Complex interactions among food components and histone modifications, DNA methylation, non-coding RNA expression and chromatin remodeling factors lead to a dynamic regulation of gene expression that controls the cellular phenotype. Although perinatal period is the time of highest phenotypic plasticity, contributing largely to developmental programming, also during adulthood there is evidence about a nutritional influence on epigenetic regulation. Similarly to type 2 diabetes, hypertension, atherosclerosis and other metabolic disorders, obesity predisposition and weight loss outcomes have been repeatedly associated to changes in epigenetic patterns. Different non-nutritional risk factors that usually accompany obesity seem also to be involved in these epigenetic modifications, especially hyperglycemia, inflammation, hypoxia and oxidative stress. There are currently three major objectives in epigenetic research in relation to obesity: to search for epigenetic biomarkers to predict future health problems or detect the individuals at most risk, to understand the obesity-related environmental factors that could modulate gene expression by affecting epigenetic mechanisms, and to study novel therapeutic strategies based on nutritional or pharmacological agents that can modify epigenetic marks. At this level, the major tasks are: development of robust epigenetic biomarkers of weight regulation, description of those epigenetic marks more susceptible to be modified by dietary exposures, identification of the active ingredients (and the doses) that alter the epigenome, assessment of the real importance of other obesity-related factors on epigenetic regulation, determination of the period of life in which best results are obtained, and understanding the importance of the inheritance of these epigenetic marks.2012-01-01T00:00:00ZAntidiabetic effects of natural plant extracts via inhibition of carbohydrate hydrolysis enzymes with emphasis on pancreatic alpha amylase
https://hdl.handle.net/10171/27969
Title: Antidiabetic effects of natural plant extracts via inhibition of carbohydrate hydrolysis enzymes with emphasis on pancreatic alpha amylase
Abstract: Introduction: The increasing prevalence of type 2 diabetes mellitus and the negative clinical outcomes observed with the commercially available anti-diabetic drugs have led to the investigation of new therapeutic approaches focused on controlling postprandrial glucose levels. The use of carbohydrate digestive enzyme inhibitors from natural resources could be a possible strategy to block dietary carbohydrate absorption with less adverse effects than synthetic drugs. Areas covered: This review covers the latest evidence regarding in vitro and in vivo studies in relation to pancreatic alpha-amylase inhibitors of plant origin, and presents bioactive compounds of phenolic nature that exhibit anti-amylase activity. Expert opinion: Pancreatic alpha-amylase inhibitors from traditional plant extracts are a promising tool for diabetes treatment. Many studies have confirmed the alpha-amylase inhibitory activity of plants and their bioactive compounds in vitro, but few studies corroborate these findings in rodents and very few in humans. Thus, despite some encouraging results, more research is required for developing a valuable anti-diabetic therapy using pancreatic alpha-amylase inhibitors of plant origin.2012-01-01T00:00:00Z