Department of Central Laboratory, Huadu District People's Hospital of Guangzhou, Guangzhou, Guangdong, 510800, China.
Department of Clinical Laboratory, Huadu District People's Hospital of Guangzhou, Guangzhou, Guangdong, 510800, China.
Cell Biochem Biophys. 2024 Sep;82(3):2055-2063. doi: 10.1007/s12013-024-01312-x. Epub 2024 May 28.
Acute kidney injury (AKI) is a multifactorial syndrome with complex pathophysiology and prognosis. Ischaemia‒reperfusion injury (IRI) is a major cause of induced AKI. The aim of this study was to investigate the effect of upregulated CXCR7 expression on renal tubular epithelial cell apoptosis induced by hypoxia/reoxygenation (H/R). HK-2 cells were divided into three groups: control group (pcDNA3.1), hypoxia/reoxygenation + pcDNA3.1 group (H/R+pcDNA3.1) and CXCR7 overexpression + hypoxia/reoxygenation group (H/R+ Flag-CXCR7). Protein levels of renal tubular epithelial cell injury-, apoptosis- and autophagy-related markers were assessed by qRT‒PCR, Western blotting, flow cytometry (FCM), immunofluorescence and transmission electron microscopy (TEM). In addition, HK-2 cells were treated with the autophagy inhibitor 3-MA and divided into 3 groups: control group, 3-MA + pcDNA3.1 group, and 3-MA + Flag-CXCR7 group. Changes in autophagy and apoptosis in renal tubule epithelial cells were assessed by Western blotting and FCM. Compared with those in the control group, the protein and mRNA expression levels of CXCR7 in HK-2 cells were significantly lower under H/R conditions. Under H/R conditions, CXCR7 overexpression in HK-2 cells significantly downregulated the expression of NGAL. Moreover, CXCR7 overexpression significantly decreased H/R-induced cleaved PARP-1 and cleaved Caspase 3 levels, increased the level of the antiapoptotic protein BCL-2 and the autophagy-related molecules ATG5 and LC3B II, and significantly inhibited the expression of P62. Autophagy flow and TEM also showed that CXCR7 significantly promoted autophagy. CXCR7 significantly alleviated the 3-MA-induced inhibition of autophagy and increase in apoptosis. Upregulated CXCR7 expression can inhibit renal tubular epithelial cell apoptosis and damage by regulating autophagy. In conclusion, CXCR7 is a promising target for the prevention and/or treatment of AKI.
急性肾损伤 (AKI) 是一种多因素综合征，具有复杂的病理生理学和预后。缺血再灌注损伤 (IRI) 是诱导 AKI 的主要原因。本研究旨在探讨上调 CXCR7 表达对缺氧/复氧 (H/R) 诱导的肾小管上皮细胞凋亡的影响。HK-2 细胞分为三组：对照组 (pcDNA3.1)、缺氧/复氧+pcDNA3.1 组 (H/R+pcDNA3.1) 和 CXCR7 过表达+缺氧/复氧组 (H/R+Flag-CXCR7)。通过 qRT-PCR、Western blot、流式细胞术 (FCM)、免疫荧光和透射电子显微镜 (TEM) 评估肾小管上皮细胞损伤、凋亡和自噬相关标志物的蛋白水平。此外，用自噬抑制剂 3-MA 处理 HK-2 细胞，并分为 3 组：对照组、3-MA+pcDNA3.1 组和 3-MA+Flag-CXCR7 组。Western blot 和 FCM 评估肾小管上皮细胞自噬和凋亡的变化。与对照组相比，HK-2 细胞在 H/R 条件下 CXCR7 的蛋白和 mRNA 表达水平明显降低。在 H/R 条件下，HK-2 细胞中 CXCR7 的过表达显著下调 NGAL 的表达。此外，CXCR7 过表达显著降低 H/R 诱导的 cleaved PARP-1 和 cleaved Caspase 3 水平，增加抗凋亡蛋白 BCL-2 和自噬相关分子 ATG5 和 LC3B II 的水平，并显著抑制 P62 的表达。自噬流和 TEM 也表明 CXCR7 显著促进自噬。CXCR7 显著缓解 3-MA 诱导的自噬抑制和凋亡增加。上调 CXCR7 表达可以通过调节自噬抑制肾小管上皮细胞凋亡和损伤。总之，CXCR7 是预防和/或治疗 AKI 的有希望的靶点。
