Inhibitory effect of ligustrazine on S1PR3 of rat renal tubular epithelial cells treated with lipopolysaccharide
Objective To investigate the effects of ligustrazine on sphingosine-1-phosphate receptor(S1PR)3 in rat renal tubule epithelial cells treated by lipopolysaccharide(LPS),and the role and mechanism of S1PR3 in sepsis-associated acute kidney injury(S-AKI).Methods The cultured NRK-52E cells were divided into control group,LPS group,and ligustrazine+LPS group.The control group received no treatment;LPS group was pretreated with 0.9%sodium chloride solution equivalent to ligustrazine for 30 min,and then cells were collected by centrifugation for examination after being stimulated with LPS(20 μg/mL)for 12 h.Ligustrazine+LPS group was pretreated with ligustrazine 200 ng/mL for 30 min,and then cells were collected by centrifugation for examination after being stimulated with LPS 20 μg/mL for 12 h.Flow cytometry was used to detect the differences of apoptosis rate,calcium ion expression and Caspase-3 expression in all groups,and ELISA was used to detect the differences of Calpain 1 and Calpain 2 expressions.The expression of S1PR3 in cells of the three groups was detected by Western blot.Results The NRK-52E cell model of sepsis was successfully established after LPS treatment.Compared with the control group,the apoptosis rate,calcium ion expression,Caspase-3 expression,S1PR3 expression,and Calpain 1 and Calpain 2 expressions in LPS group were significantly increased(all P<0.01).Compared with LPS group,apoptosis rate,calcium ion concentration,Caspase-3 expression,S1PR3 expression,Calpain 1 and Calpain 2 expressions in ligustrazine+LPS group were significantly decreased(all P<0.05).Conclusion Ligustrazine can inhibit the expression of S1PR3 and decrease the concentration of calcium ions in renal tubular epithelial cells,thereby inhibiting the apoptosis signaling pathway of Caspase-3 cells and reducing the apoptosis of renal tubular cells.S1PR3 may play an important role in the occurrence and development of S-AKI.