摘要
目的探讨阻断β-catenin基因对亚砷酸钠致大鼠肺组织氧化应激的影响。方法将48只健康SPF(specific pathogen free)级SD大鼠按性别和体质量随机分为对照组(超纯水)、低剂量组(0.45 mg/kg)、中剂量组(2.25 mg/kg)、空白对照高剂量组(11.25 mg/kg)、转染β-catenin siRNA高剂量组(11.25 mg/kg)和转染阴性对照高剂量组(11.25 mg/kg),自由经口饮水染毒16周,β-catenin siRNA转染1周。HE染色法观察大鼠肺组织病理学;石墨炉原子吸收法测定大鼠血液、尿液和肺组织中砷水平;化学荧光法测定ROS含量;ELISA法测定SOD活性、GSH和MDA含量。结果低剂量组、中剂量组和空白对照高剂量组大鼠肺组织随着染砷剂量和染砷时间的增加而呈现不同程度的炎症细胞浸润,肺泡间隔增宽,肺泡融合;空白对照高剂量组大鼠肺组织病理损伤较严重,出现部分肺组织纤维化。低剂量组、中剂量组和空白对照高剂量组大鼠血砷、尿砷和肺组织砷水平随着染砷剂量增加和染砷时间延长呈上升趋势(P<0.05)。空白对照高剂量组大鼠肺组织中ROS荧光值较对照组、低剂量组和中剂量组增加(P<0.05);MDA含量较对照组增加(P<0.05)。空白对照高剂量组大鼠肺组织中SOD和GSH含量较对照组和低剂量组减少(P<0.05)。阻断β-catenin基因后,转染β-catenin siRNA高剂量组大鼠肺组织病理损伤较空白对照高剂量组和转染阴性对照高剂量组严重,出现大部分肺组织纤维化。转染β-catenin siRNA高剂量组和转染阴性对照高剂量组大鼠血砷、尿砷和肺组织水平较对照组、低剂量组和中剂量组增加明显(P<0.05)。转染β-catenin siRNA高剂量组和转染阴性对照高剂量组大鼠肺组织中ROS荧光值较对照组、低剂量组和中剂量组增加(P<0.05);MDA含量较对照组增加(P<0.05)。而转染β-catenin siRNA高剂量组和转染阴性对照高剂量组大鼠肺组织SOD活性和GSH含量较对照组和低剂量组减少(P<0.05)。大鼠肺组织砷含量和ROS荧光值呈显著正相关(r_s=0.655,P<0.001)。大鼠肺组织中ROS荧光值与SOD活性呈低度负相关(r_s=-0.441,P<0.002);与GSH含量呈显著负相关(r_s=-0.599,P<0.001);与MDA含量呈低度正相关(r_s=0.395,P<0.006)。结论长期砷暴露使砷在大鼠体内持续性蓄积,诱导大鼠肺组织氧化应激,导致大鼠肺组织损伤。阻断β-catenin基因,对大鼠肺组织氧化应激影响较小。
Objective To investigate the effects of blocking the β-catenin gene on oxidative stress induced by sodium arsenite in rat lung. Methods 48 healthy SPF(Specific Pathogen Free) SD rats were randomly divided into control group(ultra-pure water), low dose group(0.45 mg/kg), medium dose group(2.25 mg/kg), blank control high dose group(11.25 mg/kg), high dose group transfected with β-catenin siRNA(11.25 mg/kg) and negative control high dose group(11.25 mg/kg) according to gender and body weight, free oral drinking water for 16 weeks, and β-catenin siRNA transfection for 1 week. The lung histopathology was observed by Hematoxylin-eosin(H&E) staining. The levels of arsenic in blood, urine and lung tissue of rats were determined by graphite furnace atomic absorption spectrometry. The content of ROS was determined by chemical fluorescence method. SOD activity, GSH and MDA content were determined by ELISA. Results The lung tissue of rats in low, medium and blank control high dose groups showed different degrees of inflammatory cell infiltration, alveolar septum widening and alveolar fusion with the increase of arsenic dosage. The lung tissue of rats in blank control high dose group was severely damaged and some pulmonary fibrogenesis appeared. The arsenic levels in blood, urine and lung tissues of rats in low, medium and blank control high dose groups were increased with the increase of arsenic dosage and time(P<0.05). The fluorescence values of ROS in blank control high dose group of lung tissue in rats was significantly higher than those in control, low and medium groups(P<0.05), and the content of MDA was remarkably higher than that in control group(P<0.05). SOD and GSH content in blank control high dose group was markedly lower than those in control and low dose groups(P<0.05). After blocking the β-catenin gene, most of the pulmonary fibrosis appeared in the lung tissue of rats in high dose group transfected with β-catenin siRNA, was shown to be more serious than that in blank control and negative control high dose groups. The levels of arsenic in blood, urine and lung tissue of rats in high dose group transfected with β-catenin siRNA and negative control high dose group were significantly higher than those in control, low and medium dose groups(P<0.05). The fluorescence value of ROS in lung tissue of rats in high dose group transfected with β-catenin siRNA and negative control high dose group were higher than that control, low and medium groups(P<0.05), and the content of MDA was higher than that control group(P<0.05). However, SOD and GSH contents in lung tissue of rats in high dose group transfected with β-catenin siRNA and negative control high dose group were lower than those in control and low dose groups(P<0.05). There was a significant positive correlation between arsenic content and ROS fluorescence in rat lung tissue(r_s=0.655, P<0.001). Lung tissue of ROS fluorescence was negatively correlated with SOD activity(r_s=-0.441, P<0.002), negatively correlated with GSH content(r_s=-0.599, P<0.001), and positively correlated with MDA content(r_s=0.395, P<0.006). Conclusion Long-term exposure to arsenic could cause persistent accumulation of arsenic in rats, which may result in oxidative stress in rat lung tissue and may lead to lung injury. Blocking the β-catenin gene had little effect on oxidative stress in rat lung tissue.
作者
徐梦伟
孙高峰
谢惠芳
XU Mengwei;SUN Gaofeng;XIE Huifang(Department of Occupational and Environmental Health,School of Public Health,Xinjiang Medical University,Urumqi 830011,China;Department of Non-communicable Diseases Prevention and Control,Xinjiang Urumqi Center for Disease Prevention and Control,Urumqi 830000,China)
出处
《新疆医科大学学报》
CAS
2019年第6期748-754,共7页
Journal of Xinjiang Medical University
基金
国家自然科学基金(81460480)
新疆维吾尔自治区研究生科研创新项目(XJGRI2017084)
作者简介
徐梦伟(1990-),女,在读硕士,研究方向:环境与健康;通信作者:谢惠芳,女,博士,副教授,硕士生导师,研究方向:环境与健康,E-mail:xhfworld@sina.com.
