Altered promoter methylation of PDK4, IL1 B, IL6, and TNF after Roux-en Y gastric bypass

Enhanced glucose metabolism in cultured human skeletal muscle after Roux-en-Y gastric bypass surgery

“…While long term weight loss strategies involving diet and exercise reduce plasma IL6 levels [35], the time-course effects of RYGB on myokine secretion are less clear. Systemic levels of IL6 and IL8 were unaltered 6 months after RYGB, consistent with short term weight loss interventions such as very-low calorie diet or the combination of very-low calorie diet and exercise, despite body fat reduction and improved insulin sensitivity [36,37]. Thus, IL6 and IL8 are unlikely candidates to mediate improvements in whole-body glucose homeostasis 6 months after RYGB surgery-induced weight loss.…”

DNA Methylation and Hydroxymethylation Levels in Relation to Two Weight Loss Strategies: Energy-Restricted Diet or Bariatric Surgery

“…Indeed, we hypothesized that the surgical procedure and the consequent fast weight loss could promote a reduction in IL-6 methylation, with subsequent increases in IL-6 secretion and the inflammatory state. A recent publication revealed that following a low-calorie diet before bariatric surgery did not change IL-6 promoter methylation, although the methylation increased 12 months after the Roux-en-Y gastric bypass surgery [20].…”

“…Similarly, epigenetic marks have been associated with the susceptibility or resistance to weight loss and gain [14,16,18]. On the other hand, recent studies have investigated the effect of bariatric surgery on epigenetic processes [19,20] although the results are still preliminary and controversial.…”

Altered DNA methylation of glycolytic and lipogenic genes in liver of obese and type 2 diabetic patients

“…Moreover, as the data by necessity are from a cross-sectional analysis from human subjects undergoing surgery, we are unable to establish a direct causation between altered methylation and gene expression, and it remains possible that the relationship is bidirectional. Notably, obesity-alterations in DNA methylation in whole blood, skeletal muscle, adipose tissue and liver can be partly reversed by gastric bypass [1,4,22,32], indicating DNA methylation is a dynamic process. Overall, the difference in hepatic DNA methylation between both obese patient groups and the non-obese control subjects were significant, but the changes were modest, consistent with previous findings that environmental influences, including metabolic diseases, alter DNA methylation in a site-specific and subtle manner [1,36,47,50].…”