MG-132对慢性肾衰竭大鼠主动脉及循环炎症细胞因子表达的抑制作用

Expressions of inflammatory cytokines in serum and aorta of rats with chronic renal failure

目的探讨慢性肾衰竭大鼠主动脉及循环炎症细胞因子的表达变化及蛋白酶体抑制剂MG-132的抑制作用。方法采用单肾切除、对侧肾动脉部分结扎法建立慢性肾衰竭模型,30只大鼠按随机数字表法分为假手术对照组(CON)、慢性肾衰竭组(CRF)、慢性肾衰+MG-132治疗组(CRF+M),每组10只。采用免疫组织化学方法检测主动脉TNF-α蛋白表达水平并进行图像定量分析,以ELISA法测定血清和血管内皮细胞、血管平滑肌细胞培养上清中TNF-α、IL-1β含量。结果与CON组比较,术后4个月和6个月时CRF组大鼠主动脉TNF-α阳性面积(分别为10·7%±1·3%vs4·3%±1·7%,12·6%±2·2%vs4·3%±1·1%)显著升高(P<0·01),血浆中TNF-α(分别为50·02±9·52、96·60±38·62μg/ml,P<0·01)和IL-1β(分别为9·02±1·29、11·92±0·39μg/ml,P<0·01)含量也明显增加,而大鼠体重、血浆白蛋白、血红蛋白水平却显著下降,与血浆TNF-α、IL-1β含量呈显著负相关(P<0·01)。6个月时外周血单个核细胞(PBMC)基础分泌和激发分泌TNF-α(分别为384·4±14·8、987·5±18·2pg/ml)的能力均显著增强(P<0·01)。CRF+M组应用MG-132治疗后可明显抑制慢性肾衰竭大鼠主动脉TNF-α蛋白质表达、PBMCTNF-α分泌并降低血浆中TNF-α、IL-1β含量。结论慢性肾衰竭时大鼠主动脉及循环炎症细胞因子表达均显著升高。

Objective To investigate the changes in the expression of inflammatory cytokines in serum and aorta of rats with chronic renal failure.Methods Animal model of chronic renal failure was established by single nephrectomy and partial ligation of the contralateral renal artery.The rats were randomly divided into three groups（10 each）：normal control group（Con）,chronic renal failure group（CRF）,rats with chronic renal failure and treated with proteasome inhibitor MG-132 group（CRF＋M）.The protein expression of TNFα was detected by immunohistochemistry and image analysis,the levels of TNFα and IL-1β of peripheral blood mononuclear cells（PBMC） in blood plasma and culture supernatant were detected by ELISA.Results The protein expression of TNFα 4 and 6 months after operation significantly increased in aorta of CRF group compared with that in CON group（10.7±1.3 vs 4.3±1.7,12.6±2.2 vs 4.3±1.1,P〈0.01,respectively）.The plasma levels of inflammatory cytokines TNFα and IL-1 4 and 6 months after operation were also increased significantly（TNFα：50.02±9.52μg/ml and 96.60±38.62μg/ml;IL-1：9.02±1.29μg/m and 11.92±0.39μg/ml,respectively,P〈0.01）.While the body weight,contents of serum albumin and hemoglobin were significantly decreased in CRF group,there existed an obviously negative correlation between these indexes and the levels of TNFα and IL-1β（P〈0.01）.At the sixth month after operation,the basal and stimulated secretions of TNFα were significantly increased in PBMC（384.4±14.8pg/ml and 987.5±18.2pg/ml,respectively,P〈0.01）.The TNFα protein expression in aorta,the serum concentrations of TNFα and IL-1β and the activity of PBMC were inhibited significantly by MG-132 treatment.Conclusion The expression of inflammatory cytokine is up-regulated in aorta and circulatory immunological cell of rats with chronic renal failure.