RÉSUMÉ
Objective:To investigate the effect of tofacitinib on early atherosclerosis of patients with systemic lupus erythematosus and explore the possible relationship between lupus nephritis and early atherosclerosis of systemic lupus erythematosus.Methods:Sixteen 8-week-old female MRL/lpr mice with a body weight of 20~25 g were selected and randomly divided into the treatment group and placebo group, with 8 mice in each group. The treatment group diluted tofacitinib by normal saline, and given at a dose of 10 mg·kg -1·d -1, and the placebo group (starch tablets) administered the medication in the same way as the treatment group for a total of 8 weeks. The ELISA method was applied to detect serum anti-dsDNA antibody levels in the two groups of mice. Bradford method protein concentration was used to determine the level of urine protein in mice. Automatic biochemical analyzer was used to detect blood lipids, urea nitrogen, serum creatinine, complement C3, complement C4 levels. Western blotting was used to determine the protein expression levels of monocyte chemoattractant protein-1 (MCP-1), non-receptor protein tyrosine kinase family 1 (JAK1), signal transducer and activator of transcription 1 (STAT1) and signal transducer and activator of transcription 2 (STAT2) in aortic and kidney tissues. After the aortic arch section were prepared, oil red O was used to stain the sections, and the vascular plaque area and intimal thickness were evaluated by ImageJ software. The kidneys were dissected and stained with HE, and the active lesions of lupus nephritis were evaluated using the glomerular activity scoring system. SPSS 23.0 software was used for statistical analysis, in which the between-group comparison was performed using two independent samples t-test, and the correlation analysis was performed using the Spearman method. Results:①The serum anti-dsDNA antibody expression level in the treatment group [(5.2±1.0) U/ml] was lower than that in the placebo group [(6.9±1.2) U/ml], ( Z=-3.07, P=0.008), and the levels of complement C3 and complement C4 were higher than those in the placebo group [(293±10) mg/L vs. (260±19) mg/L, Z=2.72, P=0.017]; (16±6) mg/L vs. (8±9) mg/L, Z=3.78, P=0.006]. There was no significant difference in serum BUN and Scr between the treatment group and the placebo group [(10.6±0.7) mmol/L vs. (11.5±1.1) mmol/L, Z=-1.96, P=0.071; (17±5) μmol/L vs. (22±6) μmol/L, Z=-1.79, P=0.095]. ② Compared with the placebo group, the levels of LDL, TC and TG in the treatment group decreased [(0.83±0.15) mmol/L vs. (1.08±1.05) mmol/L, Z=-3.95, P=0.001; (2.90±0.08) mmol/L vs. (1.81±0.97) mmol/L, Z=-5.17, P=0.001; (1.10±0.08) mmol/L vs. (1.60±0.42) mmol/L, Z=-3.23, P=0.013], and HDL level increased [(2.02±0.99) mmol/L vs. (1.81±0.97) mmol/L, Z=4.42, P=0.001]. ③ Compared with the placebo group, the levels of aortic MCP-1, JAK1, STAT1 and STAT2 in the treatment group were reduced [(0.17±0.30) vs. (0.23±0.05), Z=-3.06, P=0.009; (0.83±0.09) vs. (1.05±0.19), Z=-3.07, P=0.008; (0.77±0.07) vs. (0.94±0.13), Z=-2.83, P=0.014; (0.70±0.07) vs. (0.82±0.09), Z=-2.83, P=0.013], the aortic plaque area and aortic intimal thickness were lower than those in the placebo group [(12±31) μm 2vs. (1 242±1 101) μm 2, Z=-3.12, P=0.016; (63±7) μm vs. (82.10±8.06) μm, Z=-5.13, P<0.001]. ④ Compared with the placebo group, the urine protein level and glomerulonephritis activity score in the treatment group were decreased [(0.08±0.03) mg/mL vs. (0.20±0.11) mg/mL, Z=-3.08, P=0.015; (1.79±0.38) vs. (2.79±0.14) points, Z=-7.08, P<0.001)], and renal tissue MCP-1, JAK1, STAT1.Compared with the placebo group, STAT2 levels were reduced [(0.364±0.040) vs. (0.425±0.021), Z=-3.85, P=0.003; (0.689±0.074) vs. (0.838±0.068), Z=-4.19, P=0.001; (0.508±0.070) vs. (0.646±0.019), Z=-2.85, P=0.015; (0.618±0.062) vs. (0.740±0.101), Z=-2.94, P=0.013. ⑤ The glomerular mobility scores of the two groups were positively correlated with LDL, TCHO, TG, aortic plaque area and aortic intimal thickness ( r=0.51, P=0.043; r=0.79, P<0.001; r=0.64, P=0.008; r=0.82, P<0.001; r=0.74, P=0.001), and negatively correlated with HDL ( r=-0.53, P=0.036). The urine protein levels in the two groups were positively correlated with LDL, TC, TG, aortic plaque area and aortic intimal thickness ( r=0.67, P=0.004; r=0.68, P=0.004; r=0.53, P=0.033; r=0.80, P<0.001; r=0.74, P=0.001), and negatively correlated with HDL ( r=-0.57, P=0.021). Conclusion:The severity of lupus nephritis is correlated with atherosclerosis and dyslipidemia in the early stage of systemic lupus erythematosus. Tofacitinib may reduce the degree of early arteriosclerosis and lupus nephritis in MRL/LPR mice, and reduce blood lipid levels, which may be effective in improving the prognosis of SLE and improving the survival rate of patients.