Background: Studies have found that microRNAs (miRNAs) participate in the pathogenesis of myocardial ischemia-reperfusion injury (MIRI). miR-330-5p alleviated cerebral IR injury and regulated myocardial damage. However, the mechanism of the effect of miR-330-5p on MIRI needs to be further studied.
Objective: The study aimed to explore the role and mechanism of miR-330-5p in MIRI.
Methods: The oxygen-glucose deprivation reperfusion (OGD/R) model was constructed in cardiomyocytes to simulate MIRI in vitro. QRT-PCR was used for the detection of gene expression. ELISA was used for evaluation of the levels of aldehyde dehydrogenase 2 family member (ALDH2), 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA). Flow cytometry was used to evaluate apoptosis. Western blot was employed for protein determination. Bioinformatic analysis was performed for predicting the targets of miR-330-5p.
Results: miR-330-5p was found to be down-regulated in MIRI-induced cardiomyocytes (Model group). miR-330-5p mimic enhanced ALDH2 activity, inhibited apoptosis, and suppressed 4-HNE and MDA of MIRI-induced cardiomyocytes. miR-330-5p inhibited ERK expression while increasing the p38 expression. Bioinformatic analysis showed hydroxysteroid 11-beta dehydrogenase 1 (HSD11B1) to be a target of miR-330-5p. HSD11B1 expression was inhibited by miR-330-5p mimic while increased by miR-330-5p inhibitor in MIRI-induced cardiomyocytes. HSD11B1 overexpression reversed the effect of miR-330-5p on ALDH2, 4-HNE, MDA, apoptosis, and ERK/p38 signaling pathway. Furthermore, lncRNA small nucleolar RNA host gene 3 (SNHG3) was the upstream lncRNA of miR-330-5p. SNHG3 decreased miR-330-5p expression and increased HSD11B1 expression.
Conclusion: SNHG3/miR-330-5p alleviated MIRI in vitro by targeting HSD11B1 to regulate the ERK/p38 signaling pathway.