HSA-MIR-203/MyD88 axis mediates the protective effect of hispidulin on LPS-induced apoptosis in a human renal tubular epithelial line, HK-2

[摘要] Acute kidney injury (AKI), commonly occurring as complications of sepsis, cardiac surgery, and liver or kidneytransplantation, is a critical care syndrome. It is well known that lipopolysaccharide (LPS) shock is a common triggeringfactor for AKI. This study is aimed to examine the effect of flavonoid compound hispidulin on LPS-induced AKI. Forthis, renal tubular epithelial cell HK-2 was treated with LPS to establish an in vitro model of AKI. The effect ofhispidulin on HK-2 cell viability was examined using CCK-8 assay. Cell apoptosis was determined by TUNEL and flowcytometry. Apoptosis marker proteins were determined by using western blot. The levels of pro-inflammatory cytokineswere determined by ELISA assay and qRT-PCR. The translocation of NF-κB was determined by western blot. The effectof MyD88 on the cytoprotective activities of hispidulin was examined by overexpressing MyD88 in HK-2 cells. Ourresults showed that hispidulin was not able to produce a cytotoxic effect on HK-2 cells at tested concentrations.However, hispidulin could protect HK-2 cells from LPS-induced cell injury. Our results also showed that hispidulin wasable to attenuate LPS-induced HK-2 cell apoptosis. In addition, LPS led to an inflammatory response in HK-2 cells,evidenced by NF-κB p65 activation as well as increased expression and release of inflammatory cytokine IL-6 and TNF-α, which could be reversed by pretreatment with hispidulin. Overexpression MyD88 was found to significantly dampenthe cytoprotective activities of hispidulin against LPS insult. More importantly, MyD88 was identified as a direct targetof hsa-miR-203, and hispidulin was found to regulate the expression of MyD88 via upregulating hsa-miR-203. Ourresults showed that hispidulin attenuates LPS-induced HK-2 damage via regulating hsa-miR-203/MyD88 axis.

[学科分类] 仪器

[关键词] Hispidulin;LPS;HK-2;hsa-miR-203;MyD88