AUTHOR=Yang Wenkai , Tu Hanjian , Tang Kai , Huang Haozhong , Ou Shi , Wu Jianguo 

TITLE=MiR-3064 in Epicardial Adipose-Derived Exosomes Targets Neuronatin to Regulate Adipogenic Differentiation of Epicardial Adipose Stem Cells

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2021.709079

DOI=10.3389/fcvm.2021.709079

ISSN=2297-055X

ABSTRACT=<p><bold>Backgroud:</bold> The metabolism of epicardial adipose tissue (EAT) is closely related to coronary atherosclerotic heart disease (CAHD), but the specific mechanism is not fully understood. In this study, we investigated the effects of EAT microenvironment on adipose metabolism from the viewpoint of EAT-derived exosomes and epicardial adipose stem cells (EASCs).</p><p><bold>Methods:</bold> EAT samples from CAHD patients and non-CAHD patients were collected to obtain exosomes via tissue culture. MiRNA sequencing was performed to analyze differences in miRNA expression in exosomes between groups. Luciferase reporter assay was then performed to verify the miRNA target gene. EAT was digested by collagenase to obtain EASCs, which were induced to mature adipocytes <italic>in vitro</italic>. Immunochemical staining and western blotting were performed to detect protein expression levels.</p><p><bold>Results:</bold> The results showed that CAHD patients had higher levels of EASCs in EAT, and no significant difference in the adipogenic differentiation ability of EASCs was observed between CAHD and non-CAHD patients <italic>in vitro</italic>. This indicates that the EAT microenvironment is a key factor affecting the adipogenic differentiation of EASCs. The EAT-derived exosomes from CAHD patients inhibited adipogenic differentiation of EASCs <italic>in vitro</italic>. Sequencing analysis showed that miR-3064-5p was highly expressed in EAT-derived exosomes in CAHD patients, and its inhibitor could improve the adipogenic differentiation of EASCs. Luciferase reporter assay results showed that the target gene of miR-3064-5p is neuronatin (Nnat). Nnat remained silent in EASCs and was less expressed in EAT of CAHD patients.</p><p><bold>Conclusion:</bold> Abovementioned results suggest that Nnat is the key to regulating the adipogenic differentiation of EASCs, and miR-3064-5p in EAT-derived exosomes can inhibit the expression of Nnat by targeting its mRNA, thereby affecting the adipogenic differentiation of EASCs.</p>