Role of natural killer T cells in renal fibrosis in mice with acute kidney injury / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the role of natural killer T cells in renal fibrosis in mice with acute kidney injury (AKI).Methods:Twenty-four clean-grade healthy male C57BL/6 mice, aged 8-10 weeks, weighing 20-30 g, were divided into 4 groups ( n=6 each) using a random number table method: control group (group C), AKI group (group A), control plus CD1d antibody group (group C-MA), and AKI plus CD1d antibody group (group A-MA). The model of renal fibrosis in mice with AKI was established by intraperitoneal injection of folic acid 250 mg/kg.In group C, homotypic control antibody 20 mg/kg was injected via the tail vein.In group AKI, homotypic control antibody 20 mg/kg was injected via the tail vein at 24 h before establishing the model. In group C-MA, anti-CD1d monoclonal antibody 20 mg/kg was injected via the tail vein.In group A-MA, anti-CD1d monoclonal antibody 20 mg/kg was injected via the tail vein at 24 h before establishing the model.On the 14th day after folic acid injection, blood samples were taken from eyeballs to determine the concentrations of blood urea nitrogen (BUN) and creatinine (Cr) in serum.Then the mice were sacrificed, and the renal tissues were taken for Sirius red staining and HE staining to determine the area of renal fibrosis, and renal injury was scored.The expression of fibronectin (FN), type I collagen (Col-Ⅰ) and alpha-smooth muscle actin (α-SMA) in renal tissues was detected by immunofluorescence method.The expression of interleukin (IL)-4, IL-13, arginase-1 (Arg-1) and found in inflammatory zone 1 (FIZZ1) mRNA in renal tissues was detected by real-time polymerase chain reaction. Results:Compared with group C, the concentrations of BUN and Cr in serum, renal injury score, and area of renal fibrosis were significantly increased, the expression of FN, Col-Ⅰ and α-SMA and IL-4, IL-13, Arg-1 and FIZZ1 mRNA was up-regulated in A and A-MA groups ( P<0.05), and no significant change was found in the above indexes in group C-MA ( P>0.05). Compared with group A, the concentrations of BUN and Cr in serum, renal injury score, and area of renal fibrosis were significantly decreased, the expression of FN, Col-Ⅰ and α-SMA and IL-4, IL-13, Arg-1 and FIZZ1 mRNA was down-regulated in group A-MA ( P<0.05). Conclusion:Activation of natural killer T cells is involved in the process of renal fibrosis in mice with AKI, and the mechanism may be related to promoting the release of Th2 cytokines and M2 polarization of macrophages.