4种天然温石棉致大鼠肺损伤及对HO-1和HSP-70的影响

探讨了我国四大矿区天然温石棉致大鼠肺部损伤作用及肺组织中HO-1和HSP-70的表达差异。从我国四大天然矿区采集4种天然温石棉,用扫描电镜、红外光谱和X射线荧光光谱分析其粉尘形貌、表面活性基团和化学组分。将90只初断乳SPF级Wistar大鼠,随机分为5组(甘肃阿克塞、青海茫崖、四川新康、陕西陕南温石棉组和生理氯化钠溶液阴性对照组),用2. 0 mg/m L温石棉粉尘悬液0. 5 m L(1次/月)对大鼠非暴露式气管内滴注染毒。于1、6、12个月分批处死大鼠6只,测定支气管肺泡灌洗液(BALF)中的乳酸脱氢酶(LDH)、碱性磷酸酶(AKP)和总蛋白(TP)含量,采用qRT-PCR检测肺组织中血红素氧化合酶1(HO-1)和热休克蛋白70(HSP-70) mRNA表达水平,采用western blot检测肺组织中HO-1和HSP-70蛋白表达水平。结果显示,阿克塞、茫崖和新康温石棉组LDH及各温石棉组AKP和TP在各时间点均比阴性对照组高(P 0. 05),且随染毒时间延长呈上升趋势(P 0. 05)。染毒1月时,各染毒组HO-1、HSP-70 mRNA和HO-1、HSP-70蛋白表达量比阴性对照组高(P 0. 05);染毒6月时,各染毒组比阴性对照组高,阿克塞和陕南温石棉组低于茫崖和新康温石棉组(P 0. 05);染毒12月时,阿克塞和陕南温石棉组高于茫崖和新康温石棉组(P 0. 05),茫崖和新康温石棉组低于阴性对照组。

The effects of four natural chrysotile asbestos on lung injury as well as on HO-1 and HSP-70 of rats

To investigate the effects of four natural chrysotile asbestos in major mining areas of China on lung injury and the expression of HO-1 and HSP-70 in lung tissues of Wistar rats, the authors collected samples of four natural chrysotile asbestos from the four mining areas of China. The fiber morphology, surface active group and chemical composition were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray fluorescence diffraction. Wistar rats were randomly divided into 5 groups (Akesai of Gansu, Mangnai of Qinghai, Xinkang of Sichuan, chrysotile groups and physiological sodium chloride solution negative control group of southern Shaanxi), with the chrysotile groups treated with intratracheal instillation. Six rats were put to death in batches 1 month, 6 months and 12 months later respectively, and lactate dehydrogenase (LDH), alkaline phosphatase (AKP), and total protein (TP) in bronchoalveolar lavage fluid (BALF) were measured. The expression levels of heme oxygenase 1 (HO-1) and heat shock protein 70 (HSP-70) mRNA in lung tissues were detected by qRT-PCR, and the expression levels of HO-1 and HSP-70 protein were detected by western blot. The results showed that the LDH of Gansu Akesai, Qinghai Mangnai and Sichuan Xinkang chrysotile groups and the AKP and TP in each chrysotile group were higher than those in the negative control group at each time point (P<0.05), and increased with the prolonged exposure time (P<0.05). As for HO-1, HSP-70 mRNA and HO-1, HSP-70 protein expression levels, it is shown that, 1 month later, the values of each exposure group was higher than those in the negative control group (P<0.05); 6 months later, values of each exposure group was higher than those in the negative control group, and values of Gansu Akesai and southern Shaanxi chrysotile groups were lower than those in the Qinghai Mangnai and Sichuan Xinkang chrysotile groups (P<0.05); 12 months later, values of Gansu Akesai and Southern Shaanxi chrysotile groups were higher than those in the Qinghai Mangnai and Sichuan Xinkang chrysotile groups, whereas values of Qinghai Mangnai and Sichuan Xinkang chrysotile groups were lower than those in the negative control group (P<0.05).