Zhao Yan, Lv Renjun, He Yao, Dong Na, Wang Xiao, Pu Jiayuan, Yu Qin
The First School of Clinical Medicine, Lanzhou University, Lanzhou, 730000, China.
Department of Pulmonary and Critical Care Medicine, The First Hospital of Lanzhou University, Lanzhou, 730000, China.
Eur J Pharmacol. 2025 Jun 15;997:177462. doi: 10.1016/j.ejphar.2025.177462. Epub 2025 Mar 7.
Obstructive sleep apnoea hypopnea syndrome (OSAHS) is a sleep disorder associated with significant cardiovascular complications, characterized by intermittent hypoxia (IH). IH causes endothelial dysfunction, an early event in cardiovascular disease. We investigated the role of dual-specificity phosphatase 8 (DUSP8), a key negative regulator of the mitogen-activated protein kinase (MAPK) signalling pathway, in IH-induced endothelial cell damage, and the therapeutic effects of N-acetylcysteine (NAC) by establishing IH models in human umbilical vein endothelial cells and C57BL/6 mice. DUSP8 and MAPK signalling pathway-related proteins were analysed by western blotting, and DUSP8 mRNA and miR-21-5p expression was assessed by RT-qPCR. Inflammatory cytokines were detected by an enzyme-linked immunosorbent assay, apoptosis-related proteins were analysed by western blotting, and apoptosis was assessed using flow cytometry. IH stimulation induced inflammation and apoptosis in endothelial cells, downregulated DUSP8 expression, and upregulated the phosphorylation of key molecules involved in the MAPK signalling pathway. However, DUSP8 overexpression alleviated IH-induced inflammation and apoptosis in endothelial cells and reduced the phosphorylation of key molecules in the MAPK signalling pathway. Bioinformatic analysis and dual-luciferase reporter assays confirmed that DUSP8 is a direct target of miR-21-5p. DUSP8 overexpression effectively reversed the damage caused by miR-21-5p upregulation under IH conditions. Furthermore, in cell and animal models of IH, NAC demonstrated protective effects against inflammation, apoptosis, and oxidative stress through a mechanism linked to the miR-21-5p/DUSP8/MAPK signalling pathway. Overall, this study elucidated the protective role of DUSP8 against IH-induced endothelial injury and confirmed the potential of NAC as a therapeutic agent for OSAHS-related diseases.
阻塞性睡眠呼吸暂停低通气综合征（OSAHS）是一种与严重心血管并发症相关的睡眠障碍，其特征为间歇性缺氧（IH）。IH会导致内皮功能障碍，这是心血管疾病中的一个早期事件。我们通过在人脐静脉内皮细胞和C57BL/6小鼠中建立IH模型，研究了丝裂原活化蛋白激酶（MAPK）信号通路的关键负调节因子双特异性磷酸酶8（DUSP8）在IH诱导的内皮细胞损伤中的作用，以及N-乙酰半胱氨酸（NAC）的治疗效果。通过蛋白质印迹法分析DUSP8和MAPK信号通路相关蛋白，通过逆转录定量聚合酶链反应（RT-qPCR）评估DUSP8 mRNA和miR-21-5p表达。通过酶联免疫吸附测定法检测炎性细胞因子，通过蛋白质印迹法分析凋亡相关蛋白，并使用流式细胞术评估细胞凋亡。IH刺激诱导内皮细胞炎症和凋亡，下调DUSP8表达，并上调MAPK信号通路中关键分子的磷酸化。然而，DUSP8过表达减轻了IH诱导的内皮细胞炎症和凋亡，并降低了MAPK信号通路中关键分子的磷酸化。生物信息学分析和双荧光素酶报告基因测定证实DUSP8是miR-21-5p的直接靶点。DUSP8过表达有效逆转了IH条件下miR-21-5p上调所造成的损伤。此外，在IH的细胞和动物模型中，NAC通过与miR-21-5p/DUSP8/MAPK信号通路相关的机制，对炎症、凋亡和氧化应激表现出保护作用。总体而言，本研究阐明了DUSP8对IH诱导的内皮损伤的保护作用，并证实了NAC作为OSAHS相关疾病治疗药物的潜力。
