Department of Surgery, Molecular Cardiology and Angiogenesis Laboratory, University of Connecticut Health, School of Medicine, Farmington 06030, CT, USA.
Department of Surgery, Molecular Cardiology and Angiogenesis Laboratory, University of Connecticut Health, School of Medicine, Farmington 06030, CT, USA; Stanley J. Dudrick, Department of Surgery, Saint Mary's Hospital, Waterbury 06706, CT, USA.
Biochim Biophys Acta Mol Basis Dis. 2024 Jan;1870(1):166899. doi: 10.1016/j.bbadis.2023.166899. Epub 2023 Sep 29.
Ubiquitination plays a vital role in controlling vascular inflammation, cellular protein quality control, and minimizing misfolded protein toxicity. Pellino-1 (Peli1), a type of E3 ubiquitin ligase, has emerged as a critical regulator of the innate immune response; however, its role in the repair and regeneration of ischemic myocardium remains to be elucidated.
Mice (8-12 weeks old, male and females) were divided into (i) Wild type (ii) cardiomyocyte-specific Peli1 overexpressed (AMPEL1), (iii) cardiomyocyte-specific Peli1 knockout (CP1KO) and were subjected to sham and left anterior descending artery ligation. The tissues were collected at various time points after surgery for Western blot, and immunohistochemical analyses. Echocardiography is performed 30 days after myocardial infarction. Cardiomyocytes isolated from wild-type, Peli1 overexpressed and knockout mice were used to study the interaction between cardiomyocytes and endothelial cells in vitro under oxidative stress and cells were used for Western blot, flow cytometric analysis, and scratch assay.
We observed faster wound closure and increased expression of angiogenic factors with MCECs treated with conditioned media obtained from the AMPEL1 cardiomyocytes compared to CPIKO and WT cardiomyocytes. Again, AMPEL1MI mice showed preserved systolic function and reduced fibrosis compared to the CPIKOMI and WTMI groups. Capillary and arteriolar density were found to be increased in AMPEL1MI compared to CP1KOMI. Increased survival and angiogenic factors such as p-Akt, p-MK2, p-IkBα, VEGF, cIAP2, and Bcl2 were observed in AMPEL1 compared to CP1KO and WT mice subjected to MI.
The present study uncovers the crucial role of cardiac Peli1 as a regulator of the repair and regeneration of ischemic myocardium by using multiple genetically engineered mouse models.
泛素化在控制血管炎症、细胞蛋白质量控制和最小化错误折叠蛋白毒性方面发挥着至关重要的作用。Pellino-1（Peli1）是一种 E3 泛素连接酶，已成为先天免疫反应的关键调节因子；然而，其在缺血性心肌修复和再生中的作用仍有待阐明。
将 8-12 周龄雄性和雌性小鼠分为（i）野生型（ii）心肌细胞特异性 Peli1 过表达（AMPEL1）、（iii）心肌细胞特异性 Peli1 敲除（CP1KO），并进行假手术和左前降支结扎。手术后不同时间点采集组织进行 Western blot 和免疫组织化学分析。心肌梗死后 30 天进行超声心动图检查。从野生型、Peli1 过表达和敲除小鼠中分离心肌细胞，在体外氧化应激下研究心肌细胞与内皮细胞的相互作用，并进行 Western blot、流式细胞术分析和划痕实验。
与 CPIKO 和 WT 心肌细胞相比，用 AMPEL1 心肌细胞的条件培养基处理的 MCECs 观察到更快的伤口闭合和更高表达的血管生成因子。同样，与 CPIKOMI 和 WTMI 组相比，AMPEL1MI 小鼠表现出更好的收缩功能和减少的纤维化。与 CP1KOMI 相比，AMPEL1MI 中的毛细血管和小动脉密度增加。与 CP1KO 和 WT 小鼠相比，在 AMPEL1MI 中观察到存活和血管生成因子的增加，如 p-Akt、p-MK2、p-IkBα、VEGF、cIAP2 和 Bcl2。
本研究利用多种基因工程小鼠模型揭示了心脏 Peli1 作为缺血性心肌修复和再生调节因子的关键作用。
