{"title":"Deficiency of synaptotagmin-1 aggravates pressure overload-induced cardiac hypertrophy and dysfunction via the p38 MAPK signaling pathway in mice.","authors":"Jing Shen, Junqiu Miao, Lifei Wu, Deping Wang, Guang Li, Haixiong Wang, Jimin Cao","doi":"10.1007/s13577-025-01220-z","DOIUrl":null,"url":null,"abstract":"<p><p>Cardiac hypertrophy is a major risk factor for heart failure and sudden cardiac death, but its molecular mechanisms have not been well clarified. Synaptotagmin-1 (SYT1) is an important regulator of exocytosis and apoptosis and has been found expressed in the myocardium, while its functions in heart diseases have rarely been studied. Here, we investigated the role and mechanism of SYT1 in pressure overload-induced cardiac hypertrophy. Transverse aortic constriction (TAC) surgeries were performed to induce cardiac hypertrophy in global Syt1 knockout (Syt1<sup>+/-</sup>) mice and C57BL/6J wild-type (WT) littermates in vivo, with respective sham mice as negative controls. Cardiomyocyte hypertrophy was induced by angiotensin II (Ang II) in H9C2 cells in vitro. The results showed that SYT1 expression was significantly upregulated in WT-TAC mice and in Ang II-treated H9C2 cells. Blocking angiotensin receptor by losartan decreased SYT1 expression in Ang II-treated H9C2 cells. Syt1<sup>+/-</sup> mice showed significantly exacerbated cardiac hypertrophy, dysfunction, fibrosis, apoptosis and phosphorylation of myocardial p38 MAPK in response to TAC compared to WT mice. Knocking down SYT1 using siRNA in H9C2 cells aggravated Ang II-induced cell hypertrophy and apoptosis, and also enhanced p38 MAPK phosphorylation. Inhibition of p38 MAPK by SB203580 significantly alleviated the hypertrophy and apoptosis in Ang II-treated H9C2 cells. We conclude that deficiency of SYT1 aggravates pressure overload-induced cardiac hypertrophy via the p38 MAPK signaling pathway. The study elucidates a novel role of SYT1 in cardiac remodeling.</p>","PeriodicalId":49194,"journal":{"name":"Human Cell","volume":"38 3","pages":"96"},"PeriodicalIF":3.4000,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12031904/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Human Cell","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1007/s13577-025-01220-z","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Cardiac hypertrophy is a major risk factor for heart failure and sudden cardiac death, but its molecular mechanisms have not been well clarified. Synaptotagmin-1 (SYT1) is an important regulator of exocytosis and apoptosis and has been found expressed in the myocardium, while its functions in heart diseases have rarely been studied. Here, we investigated the role and mechanism of SYT1 in pressure overload-induced cardiac hypertrophy. Transverse aortic constriction (TAC) surgeries were performed to induce cardiac hypertrophy in global Syt1 knockout (Syt1+/-) mice and C57BL/6J wild-type (WT) littermates in vivo, with respective sham mice as negative controls. Cardiomyocyte hypertrophy was induced by angiotensin II (Ang II) in H9C2 cells in vitro. The results showed that SYT1 expression was significantly upregulated in WT-TAC mice and in Ang II-treated H9C2 cells. Blocking angiotensin receptor by losartan decreased SYT1 expression in Ang II-treated H9C2 cells. Syt1+/- mice showed significantly exacerbated cardiac hypertrophy, dysfunction, fibrosis, apoptosis and phosphorylation of myocardial p38 MAPK in response to TAC compared to WT mice. Knocking down SYT1 using siRNA in H9C2 cells aggravated Ang II-induced cell hypertrophy and apoptosis, and also enhanced p38 MAPK phosphorylation. Inhibition of p38 MAPK by SB203580 significantly alleviated the hypertrophy and apoptosis in Ang II-treated H9C2 cells. We conclude that deficiency of SYT1 aggravates pressure overload-induced cardiac hypertrophy via the p38 MAPK signaling pathway. The study elucidates a novel role of SYT1 in cardiac remodeling.
期刊介绍:
Human Cell is the official English-language journal of the Japan Human Cell Society. The journal serves as a forum for international research on all aspects of the human cell, encompassing not only cell biology but also pathology, cytology, and oncology, including clinical oncology. Embryonic stem cells derived from animals, regenerative medicine using animal cells, and experimental animal models with implications for human diseases are covered as well.
Submissions in any of the following categories will be considered: Research Articles, Cell Lines, Rapid Communications, Reviews, and Letters to the Editor. A brief clinical case report focusing on cellular responses to pathological insults in human studies may also be submitted as a Letter to the Editor in a concise and short format.
Not only basic scientists but also gynecologists, oncologists, and other clinical scientists are welcome to submit work expressing new ideas or research using human cells.