芳香烃受体-NOD 样受体蛋白 3 炎症信号通路在苯联合香烟暴露小鼠血液毒性中的作用

Role of aryl hydrocarbon receptor-NOD-like receptor protein 3 inflammatory signaling pathway on hematological toxicity caused by benzene combined with cigarette smoke exposure in mice

关键词: 苯  造血毒性  吸烟  芳香烃受体-NOD 样受体蛋白 3(AhR-NLRP3)炎症信号通路

Keywords: benzene  hematotoxicity  smoking  aryl hydrocarbon receptor-NOD-like receptor protein 3 (AhR-NLRP3) inflammatory signaling pathway

摘 要: 目的 探讨芳香烃受体-NOD 样受体蛋白 3(AhR-NLRP3)炎症信号通路在苯联合香烟暴露诱导的小鼠血液毒性中的表达变化及其意义。方法 采用皮下注射苯染毒法构建小鼠骨髓造血衰竭模型。将 30 只 BALB/c 小鼠随机分为 3 组,每组 10 只:对照组(皮下注射等体积玉米油 2 ml/kg)、苯染毒组(BZ,以 1 940 mg/kg 剂量皮下注射苯-玉米油混合物,每周 3 次)以及苯染毒+吸烟暴露组(BZ+Smoke),后者除进行苯染毒外,每日尚需置于染毒设备中吸入香烟烟雾(10 支/d,0.5 h/d);所有处理均持续 8 周。建模结束后,通过股骨病理学检查评估造血损伤程度,使用全自动血细胞分析仪检测外周血常规,并采用 Western blot 法检测肝组织与骨髓外周血单个核细胞(BMMNCs)中 AhR、NLRP3 及细胞色素P4501A1(CYP1A1)的蛋白表达水平。结果 股骨病理检查显示,BZ 组造血组织面积减少,非造血组织增加,BZ+Smoke 组较 BZ 组造血损伤更严重;与对照组比较,BZ 组小鼠外周血 WBC、RBC、Hb 明显下降(P<0.05), BZ+Smoke 组小鼠 WBC、 RBC 下降较 BZ 组更为显著(P<0.05);与对照组相比,BZ 组小鼠肝组织及 BMMNCs 中 AhR、NLRP3 蛋白表达水平均明显增高(P<0.05), CYP1A1 蛋白表达水平降低(P<0.05),而 BZ+Smoke 组的上述变化较 BZ 组更为显著(P<0.05)。结论 苯可能通过活化 AhR、NLRP3 炎症信号通路诱导血液毒性,香烟烟雾可以通过增加肝脏组织和骨髓细胞中 AhR、NLRP3 蛋白的表达,促进苯的血液毒性。

Abstract: Objective To investigate the expression and significance of the aryl hydrocarbon receptor-NOD-like receptor protein 3 (AhR-NLRP3)inflammatory signaling pathway in hematotoxicity induced by benzene combined with cigarette smoke in mice. Methods A mouse model of bone marrow failure was established by subcutaneous injection of benzene. Thirty BALB/c mice were randomly divided into three groups (n=10): control group (subcutaneous injection of an equal volume of corn oil 2 ml/kg), benzene exposure group (BZ, subcutaneous injection of a benzene-corn oil mixture at a dose of 1 940 mg/kg, three times per week), and benzene+smoking exposure group (BZ+Smoke), in addition to receive benzene injection, also needed to inhale cigarette smoke (10 cigarettes/ day, 0.5 h/day) via a dynamic inhalating device, all treatments lasted for 8 weeks. After the modeling, the degree of hematopoietic injury was assessed by femoral histopathology, peripheral blood routine parameters were measured using an automatic blood cell analyzer, and the protein expression levels of AhR, NLRP3, and CYP1A1 in liver tissues and bone marrow mononuclear cells (BMMNCs)were detected by Western blot. Results The pathological examination of femurs in BZ exposed mice showed that there was some decrease of hematopoietic tissue area and increase of non hematopoietic tissue, and the BZ+Smoke group had more hematopoietic damage than BZ group; compared with the control group, the peripheral blood WBC, RBC, and Hb of mice in BZ group were significantly decreased (P<0.05), while compared with BZ group, the decrease in WBC and RBC of BZ+Smoke group were more significant (P<0.05); compared with the control group, the expression levels of AhR and NLRP3 protein in liver tissues and BMMNCs of BZ group were significantly increased (P<0.05), while the expression levels of CYP1A1 protein in liver and BMMNCs were decreased (P<0.05). Compared with the BZ group, the protein expression levels of AhR and NLRP3 in liver tissue and BMMNCs were significantly increased (P<0.05), and the expression levels of CYP1A1 protein in BMMNCs were significantly decreased (P<0.05). The above changes in BZ+Smoke group were more significant than those in BZ group (P<0.05). Conclusion The results suggested that benzene might induce hematotoxicity by activating the inflammatory signaling pathways of AhR and NLRP3, while the cigarette smoke might also increases the expression of AhR and NLRP3 proteins in liver tissues and bone marrow cells, thereby promoting the hematotoxicity of benzene.