Li Chunmei, Wu Jiang, Li Yuan, Xing Guangqun
Department of Nephropathy, Qingdao, China.
Department of Vascular Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China.
Cell Physiol Biochem. 2017;41(6):2211-2220. doi: 10.1159/000475636. Epub 2017 Apr 25.
In response to various stimuli, heat shock protein 27 (Hsp27) functions as an anti-apoptotic or/and anti-inflammatory factor which confers a survival advantage to cells. This study was aimed to explore whether Hsp27 also has a cytoprotective role in human renal tubular epithelial cells, and to evaluate its potential in treating septic acute kidney injury (septic AKI).
HK-2 cells were subjected to different concentrations (0-10 µg/mL) of lipopolysaccharide (LPS) for various times (0-24 h) to establish a septic AKI model in vitro. Before LPS administration, HK-2 cells were transfected either with vectors or siRNA against Hsp27, and the changes in cell viability and apoptotic cells rate were assessed using CCK-8 and flow cytometry. The expression changes in apoptosis-related proteins, proinflammatory cytokines and chemokine, as well as main factors in NF-κB and JNK pathways were mainly determined by Western blotting. Besides, the relationship between Hsp27 and Bcl-2 was detected by co-immunoprecipitation.
LPS remarkably damaged HK-2 cells by reduction of cell viability, induction of apoptosis, and stimulation of proinflammatory cytokines and chemokine release. Hsp27 overexpression significantly impaired LPS-induced damage in HK-2 cells. Hsp27 overexpression couldn't alter the mRNA level of Bcl-2, but could interact with Bcl-2 at an endogenous level. Both NF-κB and JNK pathways were activated by LPS, while were blocked in Hsp27-overexpressing cells.
Hsp27 overexpression conferred a survival advantage to LPS-injured HK-2 cells by controlling cell viability, apoptosis and inflammation, possibly via interaction with Bcl-2 and modulation of NF-κB and JNK pathways.
热休克蛋白27（Hsp27）可响应多种刺激，作为一种抗凋亡和/或抗炎因子，赋予细胞生存优势。本研究旨在探讨Hsp27在人肾小管上皮细胞中是否也具有细胞保护作用，并评估其在治疗脓毒症急性肾损伤（脓毒症AKI）中的潜力。
将HK-2细胞暴露于不同浓度（0 - 10 µg/mL）的脂多糖（LPS）中不同时间（0 - 24小时），以在体外建立脓毒症AKI模型。在给予LPS之前，用针对Hsp27的载体或小干扰RNA转染HK-2细胞，使用CCK-8和流式细胞术评估细胞活力和凋亡细胞率的变化。凋亡相关蛋白、促炎细胞因子和趋化因子以及NF-κB和JNK途径中的主要因子的表达变化主要通过蛋白质印迹法测定。此外，通过免疫共沉淀检测Hsp27与Bcl-2之间的关系。
LPS通过降低细胞活力、诱导凋亡以及刺激促炎细胞因子和趋化因子释放，显著损伤HK-2细胞。Hsp27过表达显著减轻了LPS对HK-2细胞的损伤。Hsp27过表达不能改变Bcl-2的mRNA水平，但可在内源水平与Bcl-2相互作用。LPS激活了NF-κB和JNK途径，而在Hsp27过表达的细胞中这些途径被阻断。
Hsp27过表达通过控制细胞活力、凋亡和炎症，可能通过与Bcl-2相互作用以及调节NF-κB和JNK途径，赋予LPS损伤的HK-2细胞生存优势。
