Sort By:
Relevance
Published
Display per page:
10
20
30
50
Small ubiquitin-like modifiers inhibitors lower blood pressure via ERK5/KLF2-dependent upregulation of the eNOS/NO pathway
Nannan Tang, Jiatong Li, Zhuo Wang, Jinlu Zuo, Zifeng Zhang, Di Huang, Yannan Han, Yuqing Chen, Yilin Sun, Xiang Li, Ruxue Mu, Qingxue Ma, Jie Zhang, Jiaying Wu, He Wang, Hongxia Zhao, Xingli Dong, Zhiguo Wang, Yu Liu, Dan Zhao, Baofeng Yang
2024, 4(4): 202-211. doi: 10.1515/fzm-2024-0020
Keywords: hypertension, SUMO inhibitor, ERK5, SUMOylation, KLF2
  Background  Small ubiquitin-like modifiers (SUMO)ylation is a dynamic and reversible post-translational modification playing pivotal roles in the regulation of cancer, diabetes, heart failure, and neurological diseases. However, whether SUMO inhibitors also have anti-hypertension effect remains yet to be explored.  Methods  Blood pressure was monitored in spontaneously hypertensive rats (SHR) after Tannic acid (TA) administration for 4 weeks. The contents of nitric oxide (NO) and endothelin-1 (ET-1) in the serum of SHR were measured. Isolated endothelium-intact mesenteric artery rings were used to study relaxation effect of SUMO inhibitors. ERK5 SUMOylation was determined using coimmunoprecipitation (co-IP) and immunofluorescence (IF). NO levels were analyzed by IF. The expression levels of KLF2 and p-eNOS were semiquantified by Western blot analysis. The transcriptional activity of eNOS promotor was assayed using ChIP-PCR.  Results  Three SUMO inhibitors all reduced the phenylephrine (PE)-induced contraction of mesenteric artery rings in a concentration-dependent manner. Co-IP revealed that ponatinib promoted ERK5 SUMOylation, which was nulled following pretreatment with the SUMO inhibitors. IF displayed that TA increased ERK5 accumulation and its co-localization with SUMO-1 in the nucleus. ChIP-PCR unveiled TA-induced enhancement of KLF2-dependent eNOS promoter activity and upregulation of eNOS/NO expression in HUVECs. In vivo, TA significantly lowered the blood pressure and improved the vascular reactivity by activating the KLF2/eNOS/NO pathway. Additionally, the level of NO was elevated along with decreased ET-1 levels in the serum of SHR.  Conclusions  SUMO inhibitors inhibit ERK5 SUMOylation to promote KLF2-eNOS/NO signaling, indicating their therapeutic potential for the treatment of hypertension.
Long non-coding RNA-AK138945 regulates myocardial ischemia-reperfusion injury via the miR-1-GRP94 signaling pathway
Yanying Wang, Jian Huang, Han Sun, Jie Liu, Yingchun Shao, Manyu Gong, Xuewen Yang, Dongping Liu, Zhuo Wang, Haodong Li, Yanwei Zhang, Xiyang Zhang, Zhiyuan Du, Xiaoping Leng, Lei Jiao, Ying Zhang
2024, 4(1): 31-40. doi: 10.2478/fzm-2024-0004
Keywords: myocardial ischemia reperfusion, lncRNA, apoptosis, microRNA GRP94
  Objective  Myocardial ischemia-reperfusion injury (MIRI) is one of the leading causes of death from cardiovascular disease in humans, especially in individuals exposed to cold environments. Long non-coding RNAs (lncRNAs) regulate MIRI through multiple mechanisms.This study explored the regulatory effect of lncRNA-AK138945 on myocardial ischemia-reperfusion injury and its mechanism.  Methods  In vivo, 8- to 12-weeks-old C57BL/6 male mice underwent ligation of the left anterior descending coronary artery for 50 minutes followed by reperfusion for 48 hours. In vitro, the primary cultured neonatal mouse ventricular cardiomyocytes (NMVCs) were treated with 100 μmol/L hydrogen peroxide (H2O2). The knockdown of lncRNA-AK138945 was evaluated to detect cardiomyocyte apoptosis, and a glucose-regulated, endoplasmic reticulum stress-related protein 94 (GRP94) inhibitor was used to detect myocardial injury.  Results  We found that the expression level of lncRNA-AK138945 was reduced in MIRI mouse heart tissue and H2O2-treated cardiomyocytes. Moreover, the proportion of apoptosis in cardiomyocytes increased after lncRNA-AK138945 was silenced. The expression level of Bcl2 protein was decreased, and the expression level of Bad, Caspase 9 and Caspase 3 protein was increased. Our further study found that miR-1a-3p is a direct target of lncRNA-AK138945, after lncRNA-AK138945 was silenced in cardiomyocytes, the expression level of miR-1a-3p was increased while the expression level of its downstream protein GRP94 was decreased. Interestingly, treatment with a GRP94 inhibitor (PU-WS13) intensified H2O2-induced cardiomyocyte apoptosis. After overexpression of FOXO3, the expression levels of lncRNA-AK138945 and GRP94 were increased, while the expression levels of miR-1a-3p were decreased.  Conclusion  LncRNA-AK138945 inhibits GRP94 expression by regulating miR-1a-3p, leading to cardiomyocyte apoptosis. The transcription factor Forkhead Box Protein O3 (FOXO3) participates in cardiomyocyte apoptosis induced by endoplasmic reticulum stress through up-regulation of lncRNA-AK138945.