Recent progress in epigenetics of obesity

Abstract

Nowadays, obesity is one of the largest public health problems worldwide. In the last few decades, there has been a marked increase in the obesity epidemic and its related comorbidities. Worldwide, more than 2.2 billion people (33%) are affected by overweight or obesity (712 million, 10%) and its associated metabolic complications. Although a high heritability of obesity has been estimated, the genetic variants conducted from genetic association studies only partially explain the variation of body mass index. This has led to a growing interest in understanding the potential role of epigenetics as a key regulator of gene-environment interactions on the development of obesity and its associated complications. Rapid advances in epigenetic research methods and reduced costs of epigenome-wide association studies have led to a great expansion of population-based studies. The field of epigenetics and metabolic diseases such as obesity has advanced rapidly in a short period of time. The main epigenetic mechanisms include DNA methylation, histone modifications, microRNA (miRNA)-mediated regulation and so on. DNA methylation is the most investigated epigenetic mechanism. Preliminary evidence from animal and human studies supports the effect of epigenetics on obesity. Studies of epigenome-wide association studies and genome-wide histone modifications from different biological specimens such as blood samples (newborn, children, adolescent, youth, woman, man, twin, race, and meta-analysis), adipose tissues, skeletal muscle cells, placenta, and saliva have reported the differential expression status of multiple genes before and after obesity interventions and have identified multiple candidate genes and biological markers. These findings may improve the understanding of the complex etiology of obesity and its related comorbidities, and help to predict an individual’s risk of obesity at a young age and open possibilities for introducing targeted prevention and treatment strategies.

Epigenetics in obesity: Mechanisms and advances in therapies based on natural products

“…When energy intake/absorption exceeds energy expenditure/loss, like in sedentary lifestyle combined with energy‐dense nutrition, the surplus energy is stored in adipose tissue, leading to obesity 150 . To regulate energy metabolism, many genes are activated or deactivated, and epigenetic factors are the key methods for modifying gene expression 151 . Accordingly, the roles of epigenetic modifications in modulating energy metabolism have gained great interest.…”

Clinically Effective Molecules of Natural Origin for Obesity Prevention or Treatment

“…The main importance of epigenetics is that unlike genotype and genetic changes, epigenetic changes are modifiable and, in many cases, reversible [ 24 ]. However, epigenetic modifications that persist can be replicated and conserved in mitosis or meiosis [ 22 , 24 , 25 ] so they can be transmitted to subsequent generations [ 26 , 27 ]. Epigenetic modifications can be induced by external factors such as diet, physical activity, inflammatory processes, stress, etc., and they can occur during pregnancy or throughout life [ 21 , 25 ], with critical moments of greater susceptibility in the fetal and neonatal stages.…”

Molecular Mechanisms of Western Diet-Induced Obesity and Obesity-Related Carcinogenesis—A Narrative Review

“…Obesity results in epigenetic alterations such as DNA methylation, which has been correlated with the future development of CRC and breast cancer [ 145 , 146 , 147 , 148 , 149 ]. The other main types of epigenetic changes include histone modifications and non-coding mRNA interference.…”

“…The epigenome of mothers with pre-pregnancy obesity can be inherited by their offspring, with evidence of increased DNA methylation influencing offspring BMI z-score and body growth, which may also be sex-specific. The obesity epigenome and transgenerational inheritance were recently reviewed by Wu et al (2022) [ 148 ].…”