Department of Cardiovascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China.
Cardiac and Vascular Biology laboratory, Clinical and Translational Medicine Center, Changhai Hospital, Second Military Medical University, Shanghai, China.
Int J Biol Sci. 2024 Sep 9;20(12):4908-4921. doi: 10.7150/ijbs.95707. eCollection 2024.
: Pathological cardiac hypertrophy, a condition that contributes to heart failure, is characterized by its intricate pathogenesis. The meticulous regulation of protein function, localization, and degradation is a crucial role played by deubiquitinating enzymes in cardiac pathophysiology. This study clarifies the participation and molecular mechanism of OTUD1 (OTU Deubiquitinase 1) in pathological cardiac hypertrophy. : We generated a cardiac-specific Otud1 knockout mouse line (Otud1-CKO) and adeno-associated virus serotype 9-Otud1 mice to determine the role of Otud1 in cardiac hypertrophy. Its impact on cardiomyocytes enlargement was investigated using the adenovirus. RNA immunoprecipitation was used to validate the specific m6a methyltransferase interacted with OTUD1 transcript. RNA sequencing in conjunction with immunoprecipitation-mass spectrometry analysis was employed to identify the direct targets of OTUD1. A series of depletion mutant plasmids were constructed to detect the interaction domain of OTUD1 and its targets. : Ang II-stimulated neonatal rat cardiac myocytes and mice hearts subjected to transverse aortic constriction (TAC) showed increased protein levels of Otud1. Cardiac hypertrophy and dysfunction were less frequent in Otud1-CKO mice during TAC treatment, while Otud1 overexpression worsened cardiac hypertrophy and remodeling. METTL3 mediated m6A modification of OTUD1 transcript promoted mRNA stability and elevated protein expression. In terms of pathogenesis, Otud1 plays a crucial role in cardiac hypertrophy by targeting Pgam5, leading to the robust activation of the Ask1-p38/JNK signal pathway to accelerate cardiac hypertrophy. Significantly, the pro-hypertrophy effects of Otud1 overexpression were largely eliminated when Ask1 knockdown. : Our findings confirm that targeting the OTUD1-PGAM5 axis holds significant potential as a therapeutic approach for heart failure associated with pathological hypertrophy.
病理性心肌肥厚是心力衰竭的一个致病因素，其发病机制十分复杂。去泛素化酶在心脏病理生理学中起着精细调节蛋白质功能、定位和降解的关键作用。本研究阐明了 OTUD1（泛素特异性肽酶 1）在病理性心肌肥厚中的参与和分子机制。
我们构建了心脏特异性 Otud1 敲除鼠系（Otud1-CKO）和腺相关病毒血清型 9-Otud1 鼠，以确定 Otud1 在心肌肥厚中的作用。我们利用腺病毒研究了 Otud1 对心肌细胞增大的影响。利用 RNA 免疫沉淀实验验证了与 OTUD1 转录本特异性相互作用的 m6A 甲基转移酶。采用 RNA 测序结合免疫沉淀质谱分析，鉴定了 OTUD1 的直接靶标。构建了一系列缺失突变质粒，以检测 OTUD1 及其靶标的相互作用域。
Ang II 刺激的新生大鼠心肌细胞和接受主动脉缩窄（TAC）的小鼠心脏中，Otud1 的蛋白水平升高。在 TAC 治疗期间，Otud1-CKO 小鼠的心脏肥大和功能障碍发生率较低，而 Otud1 过表达则加重了心脏肥大和重塑。METTL3 介导的 OTUD1 转录本的 m6A 修饰促进了 mRNA 的稳定性并提高了蛋白表达。在发病机制方面，Otud1 通过靶向 Pgam5 在心肥大中发挥关键作用，从而强烈激活 Ask1-p38/JNK 信号通路，加速心脏肥大。值得注意的是，当敲低 Ask1 时，Otud1 过表达的促肥大作用大部分被消除。
我们的研究结果证实，靶向 OTUD1-PGAM5 轴具有作为病理性心肌肥厚相关心力衰竭治疗方法的巨大潜力。
