Protective effect of dihydromyricetin against lipopolysaccharide-induced HK2 cells by upregulating HIF-1α

Abstract

ABSTRACT Sepsis complicated by acute kidney injury (AKI) carries an extremely high mortality rate. The present study aimed to investigate the protective effect and underlying mechanism of dihydromyricetin (DHM) on human renal tubular epithelial cells (HK2) during AKI. To simulate an in vitro model of AKI, HK2 cells were treated with lipopolysaccharide (LPS) and divided into four groups: Control, LPS, LPS+DHM, and LPS+DHM+si-HIF-1α. The cellular viability of HK2 cells was determined by the CCK-8 assay after treatment with LPS and DHM (60 μmol/L). The expression of Bcl-2, Bax, Cleaved Caspase-3, and HIF-1α was measured by Western blotting. The expression of Bcl-2, Bax, and HIF-1α mRNA was assessed by PCR. The apoptosis rate of each group was determined by flow cytometry, while different kits were used to measure the levels of MDA, SOD, and LDH in each group of HK2 cells. DHM was found to increase the expression of HIF-1α in HK2 cells after treatment with LPS. the expression of HIF-1α mRNA and protein, Cleaved Caspase-3, Bax protein, MDA and LDH levels, and apoptosis rate were significantly decreased, while Bcl-2 protein, cell viability, and SOD activity were markedly increased in the LPS+DHM group compared with the LPS and LPS+DHM+si-HIF-1α groups. Thus, DHM can reduce apoptosis and oxidative stress damage in HK2 cells by increasing HIF-1α expression after LPS treatment. DHM may be a treatment for AKI, but in vitro studies must be validated in animal models and clinical trials before drawing conclusions. Caution must be exercised in interpreting in vitro results.