Lentivirus-Mediated Silencing of Src Homology 2 Domain-Containing Protein Tyrosine Phosphatase 2 Inhibits Release of Inflammatory Cytokines and Apoptosis in Renal Tubular Epithelial Cells Via Inhibition of the TLR4/NF-kB Pathway in Renal Ischemia-Reperfusion Injury

Abstract

Background/aims: Renal reperfusion injury occurs after the blood flow to the ischemic kidney is re-established under various clinical conditions, such as organ transplantation, renal artery stenosis, embolic disease, and the repair of descending aortic. The current study aims to explore the effects of src homology 2 domain-containing protein tyrosine phosphatase 2 (SHP-2) on the release of inflammatory cytokines and the apoptosis of renal tubular epithelial cells by regulating the TLR4/NF-κB signaling pathway in rats with renal ischemia-reperfusion (I/R) injury.

Methods: A total of 60 normal clean Sprague Dawley (SD) (WT) rats were used in this study. The levels of creatinine (Cr) and blood urea nitrogen (BUN) were determined using an automatic biochemical analyzer. The apoptosis in renal tissue was detected by TUNEL assay. The renal tubular epithelial cells of rats were cultured, infected and treated with different lentivirus vectors. The serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), IL-1β and SHP27 were measured. Reverse transcription quantitative polymerases chain reaction and Western blot analysis were performed to measure the expression of relevant genes and proteins. Furthermore, the effect of SHP-2 on the proliferation, cell cycle and apoptosis of renal tubular epithelial cells was also investigated.

Results: In the serum of rats with renal I/R injury and prolonged reperfusion time, the contents of Cr and BUN were increased, the positive expression of SHP-2 was higher, the level of apoptosis was promoted, IL-6, TNF-α, IL-1β and SHP27 expression in the serum was increased, the expression of SHP2, TLR4, NF-κB, IL-6, TNF-α and Bax was up-regulated, and the expression of Bcl-2 was down-regulated. Lentivirus-mediated silencing of SHP-2 promoted the proliferation of renal tubular epithelial cells, inhibited their apoptosis, and reduced the expression of inflammatory factors in these cells by functionally suppressing the TLR4/NF-κB signaling pathway.

Conclusion: The results indicated that lentivirus-mediated silencing of SHP-2 inhibited the release of inflammatory cytokines and the apoptosis of renal tubular epithelial cells, and promoted the proliferation of these cells by inhibiting the TLR4/NF-κB signaling pathway in rats with renal I/R injury.

Keywords: Apoptosis; Inflammatory cytokine; Renal ischemia-reperfusion injury; Renal tubular epithelial cell; Shp-2; TLR4/NF-κB signaling pathway.