RESUMO
OBJECTIVE: This study examined the correlation between serum miR-98-5p levels and indices of microvascular reperfusion in patients undergoing primary percutaneous coronary intervention (pPCI) after ST-segment elevation myocardial infarction (STEMI). Additionally, we evaluated the mechanisms by which miR-98-5p promoted ischemia/reperfusion (I/R)-induced injury in both cultured cell lines and an animal model. METHODS: Circulating miR-98-5p levels were measured and compared from 171 STEMI patients undergoing pPCI, who were divided into two groups: no-reflow and reflow. The levels of miR-98-5p, nerve growth factor (NGF), and transient receptor potential vanilloid 1 (TRPV1) were analyzed in cultured human coronary endothelial cells (HCECs) exposed to hypoxia/reoxygenation (H/R). The effects of antagomir-98-5p on myocardial I/R-induced microvascular dysfunction in vivo were evaluated. Target gene expression and activity were assessed. RESULTS: Higher miR-98-5p levels were associated with compromised indices of microvascular reperfusion. In vitro experiments on HCECs showed that exposure to H/R significantly increased miR-98-5p levels. We identified NGF as a novel target of miR-98-5p. Further, antagomir-98-5p relieved microvascular dysfunction and enhanced the expression of NGF and TRPV1 in the rat myocardial I/R model. CONCLUSIONS: MiR-98-5p promotes microvascular dysfunction by targeting the NGF-TRPV1 axis. Serum miR-98-5p serves as a potential biomarker for microvascular reperfusion.