Sivelestat Sodium Alleviates Ischemia-Reperfusion-Induced Acute Kidney Injury via Suppressing TLR4/Myd88/NF-κB Signaling Pathway in Mice

Abstract

Purpose: We aim to detect the effects of sivelestat on renal ischemia-reperfusion associated with AKI and also explore the underlying mechanism. Materials and Methods: Mice, aged between 8 and 12 weeks, were randomly allocated among four distinct groups, respectively normal saline sham group(C), normal saline surgery group(I), sivelestat (50 mg/kg) sham group(S), sivelestat (50 mg/kg) surgery group(SI) (n=6, each group). In the surgical groups, the renal pedicles of mice were clamped with non-traumatic micro-aneurysm clamps, resulting in ischemia of the kidneys for 45 minutes. This was followed by a period of reperfusion lasting 24 hours. Sham group mice underwent the identical surgery produced without clamping renal pedicles. Mice blood was obtained from eyeballs, and Serum creatinine and blood urea nitrogen levels were measured. After a 24-hour period of reperfusion, the mice were euthanized, and their kidneys were gathered for various analyses, including Western Blot (WB) analysis, RT-PCR, immunofluorescence (IF), hematoxylin and eosin (H&E) staining, and Tunel assay. Results: Pretreatments with sivelestat decreased renal Neutrophil elastase (NE), serum creatinine, and blood urea nitrogen levels after renal ischemia-reperfusion. Sivelestat also reduced histological damage and cell apoptosis in kidneys following ischemia-reperfusion injury (IRI). In addition, the sivelestat administration diminished the levels of mRNA expression of interleukin 6 (IL-6), Macrophage inflammatory protein-2 (MIP-2), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor (TNF)-α in the kidneys during IRI. The kidney tissues of the SI group had significantly mitigated TLR4, Myd88, and NF-κB p-p65 protein expression levels compared to the I group (all P<0.05). Conclusion: We demonstrated a previously unidentified mechanism that sivelestat effectively attenuates AKI-induced renal dysfunction, possibly through suppressing the TLR4/Myd88/ NF-κB pathway.