Cheng Jiangrui, Jiang Xiao, Deng Qinxiang, Ni Lei, Lin Wanghui, Cao Wenmin, Ren Pei, Xu Bingfa, Wang Qingtong, Kuai Jiajie, Wu Yonggui, Wei Wei, Wang Chun
Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Anhui Medical University, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-Inflammatory and Immune Medicine, Center of Rheumatoid Arthritis of Anhui Medical University, Hefei, 230032, China.
Department of Nephrology, the First Affiliated Hospital of Anhui Medical University, China.
Eur J Pharmacol. 2025 Sep 15;1003:177887. doi: 10.1016/j.ejphar.2025.177887. Epub 2025 Jun 30.
Studies have shown that G protein-coupled receptor kinase 2 (GRK2) undergoes functional changes in various diseases. Therefore, in this study, we examined the role of GRK2 in renal fibrosis induced by unilateral ureteral occlusion (UUO) and ischaemia-reperfusion (I/R), and evaluated the protective effect of pharmacological inhibition of GRK2.
UUO or I/R models were generated in GRK2 knockdown (GRK2-KD), GRK2 conditional-knockdown (GRK2-CKd), and wild-type (WT) mice. Biochemical markers of renal function and histopathological features of renal tissues were evaluated to assess the extent of renal fibrosis and the protective effect of pharmacological GRK2 inhibition. Transforming growth factor beta (TGF-β) and hypoxia-reoxygenation (H/R) models were established in GRK2 knockout (GRK2-KO) cells in vitro.
The UUO/I/R model mice exhibited pathological damage and increased expression of GRK2 and NADPH oxidase 4 (NOX4). Compared to the Control group, the GRK2-KD and GRK2-CKd groups presented notable amelioration of renal function and pathological features, reduced NOX4 and oxidative stress. In vitro studies revealed that knocking out GRK2 reduced NOX4 levels, ameliorated oxidative stress, moderated cellular epithelial-mesenchymal transition (EMT), improved levels of collagen Ⅰ, α-smooth muscle actin (α-SMA), and E-cadherin, as well as the cellular morphology. In addition, pharmacological treatment with GRK2-inhibitors (CP-25 or paroxetine) markedly improved UUO/I/R-induced fibrosis.
Pharmacologically blocking GRK2 using CP-25 or paroxetine effectively alleviates renal fibrosis by regulating NOX4 and oxidative stress. GRK2 represents a potential target for the prevention and treatment of renal fibrosis and inflammation.
研究表明，G蛋白偶联受体激酶2（GRK2）在各种疾病中会发生功能变化。因此，在本研究中，我们研究了GRK2在单侧输尿管梗阻（UUO）和缺血再灌注（I/R）诱导的肾纤维化中的作用，并评估了GRK2药理抑制的保护作用。
在GRK2基因敲低（GRK2-KD）、GRK2条件性基因敲低（GRK2-CKd）和野生型（WT）小鼠中建立UUO或I/R模型。评估肾功能的生化指标和肾组织的组织病理学特征，以评估肾纤维化的程度和GRK2药理抑制的保护作用。在体外GRK2基因敲除（GRK2-KO）细胞中建立转化生长因子β（TGF-β）和缺氧复氧（H/R）模型。
UUO/I/R模型小鼠表现出病理损伤，GRK2和NADPH氧化酶4（NOX4）表达增加。与对照组相比，GRK2-KD和GRK2-CKd组的肾功能和病理特征明显改善，NOX4和氧化应激降低。体外研究表明，敲除GRK2可降低NOX4水平，改善氧化应激，减轻细胞上皮-间质转化（EMT），提高Ⅰ型胶原蛋白、α平滑肌肌动蛋白（α-SMA）和E-钙黏蛋白水平，以及改善细胞形态。此外，用GRK2抑制剂（CP-25或帕罗西汀）进行药理治疗可显著改善UUO/I/R诱导的纤维化。
使用CP-25或帕罗西汀对GRK2进行药理阻断可通过调节NOX4和氧化应激有效减轻肾纤维化。GRK2是预防和治疗肾纤维化及炎症的潜在靶点。
