Effects of mesencephalic astrocyte-derived neurotrophic factor on sepsis-associated acute kidney injury

BACKGROUND:To determine the protective role of mesencephalic astrocyte-derived neurotrophic factor(MANF) in regulating sepsis-associated acute kidney injury(S-AKI).METHODS:A total of 96 mice were randomly divided into the control group,control+MANF group,S-AKI group,and S-AKI+MANF group.The S-AKI model was established by injecting lipopolysaccharide(LPS) at 10 mg/kg intraperitoneally.MANF(200 μg/kg) was administered to the control+MANF and S-AKI+MANF groups.An equal dose of normal saline was administered daily intraperitoneally in the control and S-AKI groups.Serum and kidney tissue samples were obtained for biochemical analysis.Western blotting was used to detect the protein expression of MANF in the kidney,and enzyme-linked immunosorbent assay(ELISA) was used to determine expression of MANF in the serum,pro-inflammatory cytokines(tumor necrosis factor-α [TNF-α] and interleukin-6 [IL-6]).Serum creatinine(SCr),and blood urea nitrogen(BUN)were examined using an automatic biochemical analyzer.In addition,the kidney tissue was observed for pathological changes by hematoxylin-eosin staining.The comparison between two groups was performed by unpaired Student’s t-test,and statistics among multiple groups were carried out using Tukey’s post hoc test following one-way analysis of variance(ANOVA).A P-value <0.05 was considered statistically significant.RESULTS:At the early stage of S-AKI,MANF in the kidney tissue was up-regulated,but with the development of the disease,it was down-regulated.Renal function was worsened in the S-AKI group,and TNF-α and IL-6 were elevated.The administration of MANF significantly alleviated the elevated levels of SCr and BUN and inhibited the expression of TNF-α and IL-6 in the kidney.The pathological changes were more extensive in the S-AKI group than in the S-AKI+MANF group.CONCLUSION:MANF treatment may significantly alleviate renal injury,reduce the inflammatory response,and alleviate or reverse kidney tissue damage.MANF may have a protective effect on S-AKI,suggesting a potential treatment for S-AKI.