Effect of electroacupuncture on pyroptosis in renal tubular epithelial cells of rats with acute kidney injury induced by endotoxin / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effect of electroacupuncture (EA) on pyroptosis in renal tubular epithelial cells of rats with acute kidney injury (AKI) induced by endotoxin.Methods:Twenty-four healthy clean-grade Sprague-Dawley rats of either gender, aged 6-8 weeks, weighing 160-182 g, were divided into 4 groups ( n=6 each) using a random number table method: control group (group C), group AKI, EA plus AKI group (group EA), sham EA at non-acupoint plus AKI group (group SEA). The model of endotoxemia was established by intraperitoneally injecting 10 mg/kg lipopolysaccharide.Bilateral 30 min EA stimulation of Zusanli and Shenyu (according to atlas of animal acupoint) was performed starting from 5 days before establishing the model (once a day) and at 30 min before lipopolysaccharide administration on the day of establishing the model, with disperse-dense waves, frequency of 15 Hz, and the needle was kept until 6 h after injection of LPS in group EA.EA was performed at the points 0.5 cm lateral to the acupoints of Zusanli and Shenyu in group SEA.At 6 h after LPS injection, blood was taken from the heart, and the concentrations of serum blood urea nitrogen (BUN) and creatinine (Cr) were detected by an automatic biochemical analyzer, and the serum concentrations of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by enzyme-linked immunosorbent assay.The rats were then sacrificed, and the left renal cortex was obtained for determination of pyroptosis rate of renal tubular epithelial cells (by TUNEL). The right renal cortex was obtained to detect the expression of caspase-1 and IL-1β by Western blot, and the expression of caspase-1 mRNA and IL-1β mRNA was detected by real-time polymerase chain reaction. Results:Compared with group C, the concentrations of BUN, Cr, NGAL, KIM-1, TNF-α, and IL-6 were significantly increased, the pyroptosis rate of renal tubular epithelial cells was increased, the expression of caspase-1 and IL-1β protein and mRNA in the renal cortex was up-regulated in group AKI ( P<0.05). Compared with group AKI, the concentrations of BUN, Cr, NGAL, KIM-1, TNF-α, and IL-6 were significantly decreased, the pyroptosis rate of renal tubular epithelial cells was decreased, the expression of caspase-1 and IL-1β protein and mRNA in the renal cortex was down-regulated in group SEA ( P>0.05). Conclusion:The mechanism by which EA reduces AKI may be related to inhibiting pyroptosis in renal tubular epithelial cells of rats.