摘要
目的通过对不同性别SD大鼠甲醇吸入染毒,探讨钙离子依赖性的半胱氨酸蛋白酶(calpain)、细胞周期蛋白依赖性激酶(CDK5)、膜锚定蛋白(p35、p25)在甲醇诱导大鼠神经细胞凋亡中的相关作用机制。方法将80只SFP级SD大鼠随机分为对照组及低、中、高剂量甲醇染毒组(剂量分别为25.34、50.69、101.38 g/m3),每组20只,雌雄各半。吸入染毒28 d后,测定雌雄大鼠的体重增长情况,采用TUNEL试剂盒检测大鼠脑皮质神经细胞凋亡情况,采用q-PCR法及蛋白免疫印迹法分别检测不同性别、不同剂量组大鼠皮质中calpain、p35、p25、CDK5的mRNA及蛋白表达水平。结果甲醇染毒组大鼠皮质神经细胞凋亡率与对照组相比明显升高,中、高剂量组大鼠神经细胞的凋亡率高于低剂量组,高剂量组高于中剂量组,差异有统计学意义(P<0.05或P<0.01),且随着甲醇剂量的增加,脑组织细胞凋亡越明显。对于雌性大鼠,甲醇高剂量组脑皮质p35/p25 mRNA高于对照组、低剂量组,高剂量组脑皮质calpain mRNA表达水平高于对照组,差异有统计学意义(P<0.05);对于雄性大鼠,甲醇高剂量组脑皮质p35/p25、calpain、CDK5 mRNA表达量高于对照组、低和中剂量组,差异有统计学意义(P<0.05)。相同性别间,高剂量组大鼠脑皮质中calpain、p35、CDK5蛋白表达水平明显高于对照组、低和中剂量组,中剂量组CDK5、p25蛋白表达水平均明显高于对照组,差异均有统计学意义(P<0.05)。低、中剂量组雄性大鼠p35蛋白表达水平高于对照组,差异有统计学意义(P<0.05)。结论甲醇暴露可导致雌雄大鼠大脑皮质中calpain、p25、p35、CDK5 mRNA表达及蛋白表达水平异常,并诱导神经细胞凋亡。
Objective To understand the effects of p25 and CDK5 expression on apoptosis of nerve cells of rat inhaling methanol and the related mechanism.Methods A total of 80 SD rats were randomly divided into control group and low,moderate,high methanol inhalation exposure groups(25.34,50.69 and 101.38 g/m3),20 in each,half male and half female.After 28-day exposure,the rats were weighed,TUNEL kit was used to detect the apoptosis of cerebral cortical nerve cells in rats.Gene and protein expression levels of calpain,p35,p25 and CDK5 in cortex of rats with different gender and dose were detected by q-PCR and Western blot.Results The apoptosis rates of cortical neurons in the methanol-treated groups were significantly higher compared with that in the control group(P<0.01);The apoptotic rates of cortical neurons in the moderate and high dose groups was higher compared with that in the low dose group(P<0.05),and the high dose group was higher compared with the moderate dose group(P<0.001),and with the increase of the methanol doses,the apoptotic rates of cortical neurons increased.For female rats,the expression of p35/p25 mRNA in high dose group was significantly higher compared with those in control group and low dose methanol exposure group(P<0.05),the expression level of calpain mRNA in high dose group was significantly higher compared with that in control group(P<0.05);For male rats,the expression levels of p35/p25,calpain and CDK5 mRNA in high dose methanol group were significantly higher compared with those in control group,low and moderate dose methanol exposure group(P<0.05).The expression levels of calpain,CDK5 and p25 protein in the cerebral cortex of male and female rats were significantly higher in the high dose group compared with those in the control group,low and moderate dose groups(P<0.05);The protein expression level of CDK5 and p25 in the moderate dose group was significantly higher compared with that in the control group(P<0.05).The protein expression levels of p35 in the cerebral cortex of male rats in low and moderate dose groups were significantly higher than that of the control group(P<0.05).Conclusion Exposure to methanol can cause abnormal expression of calpain,p25,p35 and CDK5 mRNA and protein in cerebral cortex of male and female rats,and can also induce neuronal apoptosis.
作者
郝乐乐
宋辉
陈楠
李宣珠
刘贺荣
HAO Le-le;SONG Hui;CHEN Nan;LI Xuan-zhu;LIU He-rong(School of Public Health,Ningxia Medical University,Yinchuan,Ningxia 750004,China)
出处
《环境与健康杂志》
CAS
北大核心
2020年第1期25-28,2,共5页
Journal of Environment and Health
基金
国家自然科学基金(81560522)
作者简介
郝乐乐(1992-),女,硕士研究生,从事职业与健康研究;通讯作者:宋辉,E-mail:songhui_ny@163.com;通讯作者:陈楠,E-mail:chennan0106@163.com
