Hu Chen-Kai, He Lei, Huang Wan-Zhong, Huang Yuan, Dai Ri-Xin, Chang Chen, Qiu Jun-Xiong, Wu Qiang, Su Qiang
Department of Cardiology, the Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, No. 1 Minde Road, Nanchang, Jiangxi, 330006, China.
Department of Cardiology, Jiangbin Hospital of Guangxi Zhuang Autonomous Region, No. 85 Hedi Road, Nanning, Guangxi, 530021, China.
Theranostics. 2025 Jun 9;15(14):6839-6856. doi: 10.7150/thno.115402. eCollection 2025.
Coronary microembolization (CME) is a severe medical condition that occurs during acute coronary syndrome, leading to myocardial inflammation, apoptosis, and cardiac dysfunction. The research investigated SRSF1 biological functions during myocardial inflammation caused by CME and its underlying mechanisms. CME models were established in rats injected with microspheres in the left ventricle and oxygen-glucose deprivation (OGD)-exposed cardiomyocytes. RT-qPCR, Western blotting and immunohistochemical staining were used to evaluate the expression of target molecules. Myocardial apoptosis was detected by flow cytometry. The direct binding between SRSF1 and ectonucleotide pyrophosphatase/phosphodiesterase 3 (ENPP3) was verified by RIP and TRAP. Protein interaction was determined by Co-IP. The dual-luciferase reporter assay measured inflammatory cytokine transcription levels. Myocardial injury was assessed by HE staining and ultrasound examinations. The study used ELISA to measure inflammatory cytokines and cardiac troponin I (cTnI) levels. SRSF1 expression was strikingly enhanced in CME models. Knockdown of SRSF1 effectively restrained NF-κB-mediated myocardial inflammation through increasing ENPP3 mRNA/lncRNA ENPP3 ratio by regulating alternative splicing of ENPP3 pre-mRNA. The GlcNAcylation of bromodomain-containing protein 4 (BRD4) was reduced during CME, which increased BRD4 protein level to trigger NF-κB-mediated inflammation. SRSF1/ENPP3 axis inhibited the GlcNAcylation of BRD4 in CME. Myocardial-specific knockout of SRSF1 restored cardiac function and restrained myocardial inflammation in CME rats by inactivation of the ENPP3/BRD4/NF-κB pathway. SRSF1 facilitates CME-induced myocardial inflammation by up-regulating ENPP3/lncRNA ENPP3 ratio to suppress GlcNAcylation of BRD4, suggesting SRSF1 inhibition as a promising therapeutic strategy for CME.
冠状动脉微栓塞（CME）是一种在急性冠状动脉综合征期间发生的严重病症，会导致心肌炎症、细胞凋亡和心脏功能障碍。该研究调查了CME引起的心肌炎症期间SRSF1的生物学功能及其潜在机制。通过向大鼠左心室内注射微球以及对心肌细胞进行氧糖剥夺（OGD）建立CME模型。采用逆转录-定量聚合酶链反应（RT-qPCR）、蛋白质免疫印迹法和免疫组织化学染色来评估靶分子的表达。通过流式细胞术检测心肌细胞凋亡。通过RNA免疫沉淀（RIP）和RNA结合蛋白免疫沉淀分析（TRAP）验证SRSF1与胞外核苷酸焦磷酸酶/磷酸二酯酶3（ENPP3）之间的直接结合。通过免疫共沉淀（Co-IP）确定蛋白质相互作用。采用双荧光素酶报告基因测定法测量炎性细胞因子的转录水平。通过苏木精-伊红（HE）染色和超声检查评估心肌损伤。该研究使用酶联免疫吸附测定（ELISA）来测量炎性细胞因子和心肌肌钙蛋白I（cTnI）水平。在CME模型中，SRSF1的表达显著增强。敲低SRSF1可通过调节ENPP3前体信使核糖核酸（pre-mRNA）的可变剪接增加ENPP3信使核糖核酸（mRNA）/长链非编码RNA ENPP3的比例，从而有效抑制核因子κB（NF-κB）介导的心肌炎症。在CME期间，含溴结构域蛋白4（BRD4）的O-连接N-乙酰葡糖胺糖基化（GlcNAcylation）减少，这会增加BRD4蛋白水平以触发NF-κB介导的炎症。在CME中，SRSF1/ENPP3轴抑制BRD4的GlcNAcylation。心肌特异性敲除SRSF1可通过使ENPP3/BRD4/NF-κB途径失活来恢复CME大鼠的心脏功能并抑制心肌炎症。SRSF1通过上调ENPP3/lncRNA ENPP3比例以抑制BRD4的GlcNAcylation，促进CME诱导的心肌炎症，这表明抑制SRSF1可能是一种有前景的CME治疗策略。
