The m6A methylation enzyme METTL14 regulates myocardial ischemia/reperfusion injury through the Akt/mTOR signaling pathway

Chunchun Wu; Youfang Chen; Yaoguo Wang; Chaoxiang Xu; Yinlian Cai; Rongcheng Zhang; Fangzhan Peng; Shengnan Wang

doi:10.1007/s11010-023-04808-x

The m⁶A methylation enzyme METTL14 regulates myocardial ischemia/reperfusion injury through the Akt/mTOR signaling pathway

Mol Cell Biochem. 2023 Jul 12. doi: 10.1007/s11010-023-04808-x. Online ahead of print.

Authors

Chunchun Wu¹, Youfang Chen², Yaoguo Wang¹, Chaoxiang Xu¹, Yinlian Cai¹, Rongcheng Zhang¹, Fangzhan Peng^#³, Shengnan Wang^#⁴

Affiliations

¹ Department of Cardiology, The Second Affiliated Hospital of Fujian Medical University, No. 42 Zhongshan North Road, Licheng Distict, Quanzhou, 362000, Fujian, China.
² Department of Clinical Medicine, Quanzhou Medical College, Quanzhou, 362000, Fujian, China.
³ Department of Emergency Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, 362000, Fujian, China.
⁴ Department of Cardiology, The Second Affiliated Hospital of Fujian Medical University, No. 42 Zhongshan North Road, Licheng Distict, Quanzhou, 362000, Fujian, China. jessewang@fjmu.edu.cn.

^# Contributed equally.

PMID: 37436654
DOI: 10.1007/s11010-023-04808-x

Abstract

Herein, we investigated the role of the m⁶A methylation enzyme METTL14 in regulating myocardial ischemia/reperfusion injury (IR/I) through the Akt/mTOR signaling pathway and related biological mechanisms. Enzyme-linked immunosorbent assay (ELISA) and fluorescence quantitative polymerase chain reaction (qPCR) were performed to detect the m⁶A mRNA and METTL3, METTL14, WTAP, and KIAA1429 levels in a mouse myocardial IR/I model. An oxygen-glucose deprivation/reperfusion (OGD/R) model was constructed by transfecting neonatal rat cardiomyocytes (NRCM) with METTL14-knockdown lentivirus. METTL14, Bax, and cleaved-caspase3 mRNA expression levels were detected using fluorescence qPCR. Apoptosis was detected using TUNEL staining. After the IR/I surgery following the adeno-associated virus injection, the METTL14 mRNA and apoptosis-related BAX/BCL2 protein expression was detected using fluorescence qPCR and western blotting, respectively. Degree of cell necrosis was detected using an LDH assay. The oxidative stress response of the myocardial tissue was detected, and IL-6 and IL-1β serum levels were detected using ELISAs. The mice injected with METTL14-knockdown AAV9 adeno-associated virus underwent IR/I surgery after the injection of an Akt/mTOR pathway inhibitor (MK2206) into the myocardial layer. Elevated mRNA m⁶A modification and m⁶A methyltransferase METTL14 levels were observed in the IR/I-injured mouse heart tissues. METTL14 knockdown significantly inhibited the OGD/R- and IR/I-induced apoptosis and necrosis in cardiac myocytes, inhibited IR/I-induced oxidative stress and inflammatory factor secretion, and activated the Akt/ mTOR pathway in vitro and in vivo. Akt/mTOR pathway inhibition significantly attenuated the alleviating effect of METTL14 knockdown on myocardial IR/I injury-induced apoptosis. Knocking down m6A methylase METTL14 inhibits IR/I-induced myocardial apoptosis and necrosis, inhibits myocardial oxidative stress and secretion of inflammatory cytokines, and activates the Akt/mTOR signaling pathway. Hence, METTL14 regulated myocardial apoptosis and necrosis in mice with IR/I through the Akt/mTOR signaling pathway.

Keywords: Akt/mTOR signaling pathway; Apoptosis; METTL14; Myocardial ischemia; Necrosis; Oxidative stress response; Reperfusion injury.

Abstract

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