Background: Obesity is a multifactorial chronic disease resulting from sustained energy imbalance and modulated by environmental and demographic factors, and it is associated with numerous comorbidities. DNA methylation is an epigenetic modification associated with obesity. Modulation of DNA methylation is a viable target for obesity control strategies. The flavanol (-)-epicatechin (EC) exerts beneficial effects in overweight individuals, suggesting that EC may influence gene regulation through signaling pathways and epigenetic mechanisms. We evaluated whether EC modulates obesity-associated DNA methylation changes using complementary in silico, in vitro, and in vivo approaches. Methods. In silico analyses were performed to explore potential EC interactions with the DNA methyltransferases DNMT1, DNMT3A, and DNMT3B. DNMT activity was measured in nuclear extracts of 4T1 cells in the presence of EC. Finally, in a C57BL/6 mouse model of diet- induced obesity, we assessed global DNA methylation and the expression of the DNA methyltransferases, as well as metabolism-related genes; peroxisome proliferator-activated receptor gamma coactivator 1 alpha (Pgc-1α), pyruvate dehydrogenase kinase isozyme 4 (Pdk4), and nuclear factor erythroid 2–related factor 2 (Nrf2) and relative mitochondrial DNA content (mtDNA/nDNA ratio) in visceral adipose tissue (VAT) and skeletal muscle. Results. EC showed stable in silico interactions within catalytic/cofactor-binding regions of DNMTs and inhibited DNMT activity in vitro in a concentration-dependent manner. In vivo, the obesogenic diet reduced global DNA methylation and decreased transcript levels of Dnmt1, Dnmt3a, and Dnmt3b in skeletal muscle and adipose tissue. EC counteracted obesity-associated DNA methylation changes in skeletal muscle, restoring global methylation and Dnmt expression toward control levels, whereas effects in VAT were limited. EC increased mitochondrial DNA content. Discussion. In silico and enzymatic data suggest that EC may bind DNMT active sites and inhibit DNMT activity in a concentration-dependent manner, supporting a role for EC in obesity-related epigenetic remodeling, particularly in skeletal muscle. EC also increased relative mitochondrial DNA content in VAT and skeletal muscle despite no obesogenic diet effect on relative mitochondrial abundance, consistent with favorable mitochondrial modulation. In conclusion, EC is an epigenetic modulator and may have positive effects in obesity related dysfunctional tissues.
Pérez-Durán et al. (Tue,) studied this question.