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Revascularization of coronary chronic total occlusion (CTO) still remains controversial. The factors that impact collateral circulation and myocardial perfusion are of interest. Circular RNA (circRNA) has been shown to regulate the process of angiogenesis. However, the effects of circ-membrane-bound O-acyltransferase domain containing 2 (<i>circ-MBOAT2</i>) on angiogenesis in patients with CTO were unclear. In this study, we evaluated circulating circRNAs and miRNAs in patients with CTO and stable coronary artery disease using high-throughput sequencing. Another cohort of patients were selected to verify the expressions of <i>circ-MBOAT2</i> and <i>miR-495</i>. The role and mechanism of <i>circ-MBOAT2</i> in the process of angiogenesis were explored through in vitro and vivo studies. Finally, we came back to a clinical perspective and investigated whether <i>circ-MBOAT2</i> and <i>miR-495</i> were associated with the improvement of myocardial perfusion evaluated by single-photon emission computed tomography (SPECT). We found that the expression of <i>circ-MBOAT2</i> was significantly up-regulated while <i>miR-495</i> was significantly down-regulated in patients with CTO. The expression of <i>circ-MBOAT2</i> was negatively correlated with <i>miR-495</i> in patients with CTO. In an in vitro study, we found that <i>circ-MBOAT2</i> promoted tube formation and cell migration via the <i>miR-495</i>/NOTCH1 axis in endothelial cells. In an in vivo study, we showed that the inhibition of <i>miR-495</i> caused the increase in collateral formation in mice after hindlimb ischemia. In a human study, we showed the expressions of <i>circ-MBOAT2</i> and <i>miR-495</i> were associated with myocardial perfusion improvement after revascularization of CTO. In conclusion, <i>circ-MBOAT2</i> regulates angiogenesis via the <i>miR-495</i>/NOTCH1 axis and associates with myocardial perfusion in patients with CTO. Our findings suggest that <i>circ-MBOAT2</i> and <i>miR-495</i> may be potential therapeutic targets and prognostic factors for patients with CTO.