AUTHOR=Zhou Yaliang , Tan Chunlu TITLE=miRNAs in Adipocyte-Derived Extracellular Vesicles: Multiple Roles in Development of Obesity-Associated Disease JOURNAL=Frontiers in Molecular Biosciences VOLUME=7 YEAR=2020 URL=https://www.frontiersin.org/journals/molecular-biosciences/articles/10.3389/fmolb.2020.00171 DOI=10.3389/fmolb.2020.00171 ISSN=2296-889X ABSTRACT=

Obesity and overweight are common modern health challenges. Caloric intake greater than that needed for energy production results in excess storage of fat in the abdomen. Visceral fat secretes a wide spectrum of adipokines, and increased adiposity is associated with a higher risk of development of metabolic disorders. In addition, adipose tissue secretes extracellular vesicles (EVs) to communicate with peripheral cells and distant organs, and regulate whole-body metabolism. Furthermore, clinical evidence has shown that adipose tissue-derived EVs are present at low levels in the circulation of healthy individuals. In contrast, individuals with metabolic syndrome have significantly higher levels of circulating adipose-derived EVs. The composition of the contents of EVs is dynamic, and closely mirrors individual daily habits and fasting-fed state metabolic characteristics. In this mini-review, we aimed to elucidate the role of adipocyte-derived EVs in regulation of whole-body metabolism under physiological and pathophysiological conditions. Studies have shown that adipose tissue may be a major source of circulating exosomal miRNAs that regulate metabolic homeostasis and directly promote insulin-resistance in other organs. Furthermore, the composition of adipocyte-derived circulating miRNAs in EVs may change prior to development of metabolic disorder. Adipocyte-derived miRNAs in EVs may also induce obesity-related changes such as M1 polarization and inhibition of M2 polarization of macrophages, which may affect the biological behaviors of surrounding tumor cells.