Ambrosini Samuele, Montecucco Fabrizio, Kolijn Detmar, Pedicino Daniela, Akhmedov Alexander, Mohammed Shafeeq A, Herwig Melissa, Gorica Era, Szabó Petra L, Weber Lukas, Russo Giulio, Vinci Ramona, Matter Christian M, Liuzzo Giovanna, Brown Peter J, Rossi Fabio M V, Camici Giovanni G, Sciarretta Sebastiano, Beltrami Antonio P, Crea Filippo, Podesser Bruno, Lüscher Thomas F, Kiss Attila, Ruschitzka Frank, Hamdani Nazha, Costantino Sarah, Paneni Francesco
Center for Molecular Cardiology, University of Zürich, Wagistrasse 12, 8952 Schlieren, Switzerland.
First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, viale Benedetto XV, 16132, Genoa, Italy.
Cardiovasc Res. 2023 Jan 18;118(17):3374-3385. doi: 10.1093/cvr/cvac102.
Methylation of non-histone proteins is emerging as a central regulatory mechanism in health and disease. The methyltransferase SETD7 has shown to methylate and alter the function of a variety of proteins in vitro; however, its function in the heart is poorly understood. The present study investigates the role of SETD7 in myocardial ischaemic injury.
Experiments were performed in neonatal rat ventricular myocytes (NRVMs), SETD7 knockout mice (SETD7-/-) undergoing myocardial ischaemia/reperfusion (I/R) injury, left ventricular (LV) myocardial samples from patients with ischaemic cardiomyopathy (ICM), and peripheral blood mononuclear cells (PBMCs) from patients with ST-elevation MI (STEMI). We show that SETD7 is activated upon energy deprivation in cultured NRVMs and methylates the Hippo pathway effector YAP, leading to its cytosolic retention and impaired transcription of antioxidant genes manganese superoxide dismutase (MnSOD) and catalase (CAT). Such impairment of antioxidant defence was associated with mitochondrial reactive oxygen species (mtROS), organelle swelling, and apoptosis. Selective pharmacological inhibition of SETD7 by (R)-PFI-2 restored YAP nuclear localization, thus preventing mtROS, mitochondrial damage, and apoptosis in NRVMs. In mice, genetic deletion of SETD7 attenuated myocardial I/R injury, mtROS, and LV dysfunction by restoring YAP-dependent transcription of MnSOD and CAT. Moreover, in cardiomyocytes isolated from I/R mice and ICM patients, (R)-PFI-2 prevented mtROS accumulation, while improving Ca2+-activated tension. Finally, SETD7 was up-regulated in PBMCs from STEMI patients and negatively correlated with MnSOD and CAT.
We show a methylation-dependent checkpoint regulating oxidative stress during myocardial ischaemia. SETD7 inhibition may represent a valid therapeutic strategy in this setting.
非组蛋白的甲基化正成为健康与疾病中的一种核心调控机制。甲基转移酶SETD7已被证明在体外可使多种蛋白质发生甲基化并改变其功能；然而，其在心脏中的功能却鲜为人知。本研究旨在探究SETD7在心肌缺血损伤中的作用。
实验在新生大鼠心室肌细胞（NRVMs）、经历心肌缺血/再灌注（I/R）损伤的SETD7基因敲除小鼠（SETD7-/-）、缺血性心肌病（ICM）患者的左心室（LV）心肌样本以及ST段抬高型心肌梗死（STEMI）患者的外周血单个核细胞（PBMCs）中进行。我们发现，在培养的NRVMs中，能量剥夺会激活SETD7，使其对Hippo信号通路效应分子YAP进行甲基化，导致YAP滞留于细胞质中，抗氧化基因锰超氧化物歧化酶（MnSOD）和过氧化氢酶（CAT）的转录受损。这种抗氧化防御功能的损害与线粒体活性氧（mtROS）、细胞器肿胀及细胞凋亡相关。（R）-PFI-2对SETD7的选择性药理抑制可恢复YAP的核定位，从而预防NRVMs中的mtROS、线粒体损伤及细胞凋亡。在小鼠中，SETD7基因缺失通过恢复YAP依赖的MnSOD和CAT转录，减轻了心肌I/R损伤、mtROS及左心室功能障碍。此外，在从I/R小鼠和ICM患者分离的心肌细胞中，（R）-PFI-2可预防mtROS积累，同时改善Ca2+激活的张力。最后，SETD7在STEMI患者的PBMCs中上调，且与MnSOD和CAT呈负相关。
我们发现了一种在心肌缺血期间调节氧化应激且依赖甲基化的检查点。在这种情况下，抑制SETD7可能是一种有效的治疗策略。
