Adipose Tissue Macrophages Modulate Obesity-Associated β Cell Adaptations through Secreted miRNA-Containing Extracellular Vesicles.

ABSTRACT: Obesity induces an adaptive expansion of β cell mass and insulin secretion abnormality. Expansion of adipose tissue macrophages (ATMs) is a hallmark of obesity. Here, we assessed a novel role of ATMs in mediating obesity-induced β cell adaptation through the release of miRNA-containing extracellular vesicles (EVs). In both in vivo and in vitro experiments, we show that ATM EVs derived from obese mice notably suppress insulin secretion and enhance β cell proliferation. We also observed similar phenotypes from human islets after obese ATM EV treatment. Importantly, depletion of miRNAs blunts the effects of obese ATM EVs, as evidenced by minimal effects of obese DicerKO ATM EVs on β cell responses. miR-155 is a highly enriched miRNA within obese ATM EVs and miR-155 overexpressed in β cells im

SUBMITTER: Gao H 

PROVIDER: S-EPMC8472266 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature