Chen Ye, Chen Shuo, Wu Miao, Chen Fang, Guan Qianjun, Zhang Sen, Wen Jiyue, Sun Zhongwu, Chen Zhiwu
Department of Pathology, The First Affiliated Hospital of Anhui Medical University, Hefei 230000, Anhui, China.
Department of Pharmacology, School of Basic Medical Sciences, Anhui Medical University, Hefei 230000, China.
ACS Omega. 2024 Mar 11;9(11):13227-13238. doi: 10.1021/acsomega.3c10006. eCollection 2024 Mar 19.
The protective role of hydrogen sulfide against cerebral ischemia-reperfusion injury involves the inhibition of the RhoA-/Rho-associated coiled-coil kinase (ROCK) pathway. However, the specific mechanism remains elusive. This study investigates the impact of hydrogen sulfide on RhoA phosphorylation at serine 188 (Ser188) in vivo, aiming to test the hypothesis that hydrogen sulfide exerts neuroprotection by enhancing RhoA phosphorylation at Ser188, subsequently inhibiting the RhoA/ROCK pathway. Recombinant RhoA-pEGFP-N1 and RhoA-pEGFP-N1 plasmids were constructed and administered via stereotaxic injection into the rat hippocampus. A rat global cerebral ischemia-reperfusion model was induced by bilateral carotid artery ligation to elucidate the neuroprotective mechanisms of hydrogen sulfide. Both RhoA-pEGFP-N1 and RhoA-pEGFP-N1 plasmids expressed RhoA and RhoA proteins, respectively, in rat hippocampal tissues, alongside the intrinsic RhoA protein. Systemic administration of the exogenous hydrogen sulfide donor sodium hydrosulfide led to an increase in Ser188 phosphorylation of transfected RhoA and intrinsic RhoA protein within the hippocampus. However, this effect was not observed in tissues transfected with RhoA. Sodium hydrosulfide-mediated RhoA phosphorylation correlated with decreased RhoA and ROCK activity in rat hippocampal tissues. Furthermore, sodium hydrosulfide administration reduced cerebral ischemia-reperfusion-induced neuronal damage and apoptosis in rat hippocampal tissues transfected with RhoA. However, this neuroprotective effect was attenuated in rats transfected with RhoA. These findings suggest that the neuroprotective mechanism of hydrogen sulfide against cerebral ischemia/reperfusion injury involves increased RhoA phosphorylation at Ser188. Promoting this phosphorylation may represent a potential intrinsic therapeutic target for ischemic stroke.
硫化氢对脑缺血再灌注损伤的保护作用涉及对RhoA/ Rho相关卷曲螺旋蛋白激酶（ROCK）信号通路的抑制。然而，具体机制仍不清楚。本研究旨在探讨硫化氢对体内RhoA丝氨酸188（Ser188）位点磷酸化的影响，以验证硫化氢通过增强Ser188位点RhoA磷酸化、进而抑制RhoA/ROCK信号通路发挥神经保护作用的假说。构建重组RhoA-pEGFP-N1和RhoA-pEGFP-N1质粒，并通过立体定位注射导入大鼠海马体。采用双侧颈动脉结扎法建立大鼠全脑缺血再灌注模型，以阐明硫化氢的神经保护机制。RhoA-pEGFP-N1和RhoA-pEGFP-N1质粒分别在大鼠海马组织中表达RhoA和RhoA蛋白，同时存在内源性RhoA蛋白。全身给予外源性硫化氢供体硫氢化钠可导致海马体内转染的RhoA和内源性RhoA蛋白的Ser188磷酸化增加。然而，在转染RhoA的组织中未观察到这种效应。硫氢化钠介导的RhoA磷酸化与大鼠海马组织中RhoA和ROCK活性降低相关。此外，给予硫氢化钠可减少脑缺血再灌注诱导的转染RhoA的大鼠海马组织中的神经元损伤和凋亡。然而，在转染RhoA的大鼠中，这种神经保护作用减弱。这些发现表明，硫化氢对脑缺血/再灌注损伤的神经保护机制涉及Ser188位点RhoA磷酸化增加。促进这种磷酸化可能是缺血性中风潜在的内在治疗靶点。
