Effect of dexmedetomidine on kidney injury in sepsis rats through TLR4/MyD88/NF-κB/iNOS signaling pathway.

The aim of this study was to investigate the effect of dexmedetomidine (DEX) on kidney injury in sepsis rats through the Toll-like receptor 4 (TLR4)/myeloid differential protein-88 (MyD88)/nuclear factor-κB (NF-κB)/inducible nitric oxide synthase (iNOS) signaling pathway.A total of 30 Sprague-Dawley (SD) rats were randomly divided into three groups, including the control group (n=10), lipopolysaccharide (LPS)-induced acute kidney injury (AKI) group (model group, n=10) and DEX treatment group (DEX group, n=10). The model of sepsis was successfully established in rats. The levels of serum creatinine (Cr), blood urea nitrogen (BUN), serum interleukin-6 (IL-6), IL-1β, IL-10 and tumor necrosis factor-α (TNF-α) were detected via enzyme-linked immunosorbent assay (ELISA). The pathological changes in kidney tissues were detected via hematoxylin-eosin (HE) staining. Furthermore, the mRNA and protein expressions of TLR4, MyD88, NF-κB, and iNOS in the kidney were detected via fluorescence quantitative Polymerase Chain Reaction (PCR) and Western blotting, respectively.Compared with the control group, rats in the model group showed significant kidney injury, markedly increased levels of serum Cr, BUN and pro-inflammatory cytokines, remarkably decreased the level of IL-10 (p<0.05), and significantly increased mRNA and protein expressions of TLR4, MyD88, NF-κB, and iNOS. In the DEX group, AKI was markedly improved, while the expressions of inflammatory cytokines were remarkably declined. Furthermore, the mRNA and protein expressions of TLR4, MyD88, NF-κB, and iNOS decreased significantly.DEX has a protective effect on LPS-induced AKI, whose mechanism may be related to the inhibition of the TLR4/MyD88/NF-κB/iNOS pathway.