摘要
目的 探讨Nrf2通路在铅暴露和高盐饮食作用下小脑氧化损伤中的作用,以期为铅暴露和高盐饮食致小脑损伤机制提供理论依据。方法 60只SPF级雄性C57BL/6小鼠,随机分为对照组、高盐饮食组(高盐组)、铅暴露组(铅组)和铅暴露+高盐饮食组(铅+高盐组),每组15只。高盐组给予高盐饲料同时饮用含1%NaCl水溶液喂养,铅组饮用质量浓度为250 mg/L的醋酸铅饮用水,铅+高盐组给予高盐饲料喂养同时饮用质量浓度为250 mg/L的醋酸铅及1%NaCl水溶液,染毒时间为12周。采取小动物无创血压检测仪测量小鼠舒张压及收缩压;应用平衡木实验进行小鼠运动功能测试;采用苏木素—伊红(HE)染色法观察小脑组织病理学变化;利用电感耦合等离子体质谱仪检测小脑组织中铅水平,应用试剂盒检测小脑组织MDA含量及SOD和CAT活性,应用实时-PCR检测小脑Nrf2、HO-1和NQO1的mRNA水平。结果 染毒12周后,高盐组、铅+高盐组小鼠舒张压及收缩压均升高,差异有统计学意义(P<0.05)。铅组小鼠通过平衡木时间高于对照组,差异有统计学意义(P<0.05)。铅+高盐组打滑次数高于高盐组,差异有统计学意义(P<0.05)。组织病理学结果显示铅+高盐组浦肯野细胞数量较对照组明显减少,排列松散紊乱,深染细胞增多。铅组和铅+高盐组小鼠小脑铅水平较对照组和高盐组均升高,差异有统计学意义(P<0.05)。铅组、铅+高盐组小鼠小脑CAT活性较对照组降低,MDA含量较对照组升高,且铅+高盐组小鼠小脑SOD和CAT活性明显低于高盐组和铅组,MDA含量明显高于高盐组和铅组,差异有统计学意义(P<0.05)。铅组较对照组小鼠小脑Nrf2、HO-1和NQO1的mRNA表达水平降低,且铅+高盐组小鼠小脑组织中Nrf2、HO-1和NQO1 mRNA表达明显低于高盐组或铅组,差异有统计学意义(P<0.05)。结论 长期高盐饮食铅暴露可抑制小鼠小脑Nrf2信号通路活化导致抗氧化损伤水平降低,进而加剧小脑氧化应激损伤。
Objective To explore the role of Nrf2 pathway in cerebellar oxidative damage caused by lead exposure and high-salt diet, in order to provide a theoretical basis for the mechanism of lead exposure and high-salt diet-induced cerebellar damage. Methods Sixty SPF-grade male C57 BL/6 mice were randomly divided into a control group, a high-salt diet group(high-salt group), a lead exposure group(lead group), and a lead exposure + high-salt diet group(lead + high-salt group), with 15 mice in each group. The high-salt group was given high-salt feed while drinking 1% NaCl aqueous solution for feeding, the lead group drank lead acetate drinking water with a mass concentration of 250 mg/L, and the lead+high-salt group was fed with high-salt feed while drinking the mass concentration 250 mg/L lead acetate and 1% NaCl aqueous solution, the exposure time was 12 weeks. The blood pressure of mice was measured by non-invasive blood pressure monitor;the motor function test was performed by the balance beam experiment;the pathological changes of the cerebellar tissue were observed by the HE staining;the lead level in the cerebellum tissue was detected by the inductively coupled plasma mass spectrometer, and the cerebellum was detected by the kit Tissue MDA content and SOD and CAT activities, and realtime-PCR was used to detect the mRNA levels of Nrf2, HO-1 and NQO1 in the cerebellum. Results After 12 weeks of exposure, the diastolic and systolic blood pressure of the mice in the high-salt group and the lead+high-salt group increased, and the difference was statistically significant. The lead group of mice passed the balance beam longer than the control group, the difference was statistically significant. The number of slips in the lead+high-salt group was higher than that in the high-salt group, and the difference was statistically significant. Histopathological result showed that the number of Purkinje cells in the lead+high-salt group was significantly reduced compared with the control group, the arrangement was loose and disordered, and the number of deeply stained cells increased. The lead level of mice in the lead group and the lead+high-salt group increased compared with the control group and the high-salt group, and the difference was statistically significant. The activity of CAT in the cerebellum of mice in the lead group and the lead + high-salt group was lower than that of the control group, and the MDA content was higher than that of the control group. The SOD and CAT activities in the cerebellum of mice in the lead + high-salt group were significantly lower than those of the high-salt group and the lead group. The MDA content in the lead+high-salt group was significantly higher than that of the high-salt group and the lead group, and the difference was statistically significant. The mRNA expression levels of Nrf2, HO-1 and NQO1 in the cerebellum of the lead group decreased compared with the control group, and the mRNA expression level of Nrf2, HO-1 and NQO1 in the cerebellum of the lead + high-salt group was significantly lower than that of high-salt group and the lead group and the difference was statistically significant. Conclusion Long-term lead exposure and high-salt diet can inhibit the activation of the Nrf2 signaling pathway in the cerebellum of mice, leading to a decrease in the level of anti-oxidative damage, that aggravating cerebellar oxidative stress damage.
作者
朱毅
吴磊
王伟轩
张学彦
韩晔
张连胜
张丽锦
李爽
张艳淑
ZHU Yi;WU Lei;WANG Wei-xuan;ZHANG Xue-yan;HAN Ye;ZHANG Lian-sheng;ZHANG Li-jin;LI Shuang;ZHANG Yan-shu(School of Public Health,North China University of Technology,Tangshan Hebei 063210,China;Laboratory Animal Center,North China University of Technology,Tangshan Hebei 063210,China)
出处
《毒理学杂志》
CAS
CSCD
2022年第2期124-129,共6页
Journal of Toxicology
基金
国家自然科学基金(81673208)
河北省自然科学基金(H2020209177)
河北省教育厅科技项目(QN2021121)
河北省中医药类科研计划课题(2018173)。
关键词
铅
高盐饮食
小脑
氧化损伤
NRF2
Lead
High salt diet
Cerebellum
Oxidative damage
Nrf2
作者简介
朱毅,硕士研究生在读,研究方向:神经毒理学;通讯作者:张艳淑,教授,研究方向:神经毒理学;通讯作者:李爽,副教授,研究方向:神经毒理学。
