氟氯氰菊酯通过GADD45B介导JNK/p38MAPK通路对大鼠肾脏损伤的影响

Effect of Cyfluthrin on Renal Injury in Rats through GADD45B-mediated JNK/p38MAPK Pathway

目的 探讨氟氯氰菊酯暴露通过影响生长停滞和DNA损伤诱导β(GADD45B)水平并介导JNK/p38MAPK通路对大鼠肾脏损伤的影响。方法 将40只SPF级Wistar雄性大鼠按随机数表法分为4组,即对照组、氟氯氰菊酯低剂量组、中剂量组、高剂量组,每组10只。隔天灌胃连续染毒28 d,取肾脏组织称量后计算脏器系数。HE染色光镜下观察大鼠肾脏组织病理形态变化;透射电镜观察肾脏细胞超微结构变化;应用试剂盒检测肾脏组织中氧化损伤指标超氧化物歧化酶(SOD)、丙二醛(MDA)含量变化;应用Western blot、qPCR检测GADD45B、p38MAPK、p-p38MAPK、JNK、p-JNK mRNA及蛋白表达水平变化。结果 与对照组相比,氟氯氰菊酯染毒大鼠体质量增长、肾脏质量和脏器系数的差异均无统计学意义(P均>0.05);HE染色结果显示:与对照组相比,随着氟氯氰菊酯染毒剂量的增加,肾小管肿胀越发明显,肾小管上皮细胞大量脱落,肾小球萎缩。透射电镜结果显示:与对照组相比,随着氟氯氰菊酯染毒剂量的增加,基底膜逐渐增厚,线粒体和内质网出现不同程度损伤。与对照组比较,低、中、高剂量组MDA含量均升高(P均<0.05)、SOD活力均降低(P均<0.05)。与对照组相比,氟氯氰菊酯低、中、高剂量组中GADD45B的mRNA表达水平均升高(P均<0.05);JNK和p38MAPK的mRNA表达水平均降低(P均<0.05)。Western blot结果显示,与对照组比较,氟氯氰菊酯低、中、高剂量组中GADD45B、p-JNK、p-p38的蛋白表达水平均升高(P均<0.05);JNK和p38的蛋白表达水平均降低(P均<0.05)。结论 在氟氯氰菊酯致大鼠肾脏损伤中,GADD45B可通过激活JNK/p38MAPK通路诱导大鼠肾脏损伤。

Objective To explore the role of growth arrest and DNA damage-inducible 45β(GADD45B)in renal injury induced by cyfluthrin in rats by regulating JNK/p38MAPK. Methods Forty SPF Wistar male rats were randomly divided into 4 groups:control group,cyfluthrin low-dose,medium-dose and high-dose groups,with 10 rats in each group. After 28 days of continuous exposure,After execution,the kidneys of the rats were weighed and the organ coefficients were calculated,the morphological changes of kidney were observed by HE staining;transmission electron microscopy was used to observe the ultrastructural changes of renal cells. The changes of superoxide dismutase(SOD)and malondialdehyde(MDA)in renal tissue homogenate were detected by kits. Western blot and qPCR were used to detect the protein and mRNA expression levels of GADD45B and p38MAPK,p-p38MAPK,JNK,p-JNK. Results Compared with the control group,there were no statistically significant differences in weight gain,kidney weight and organ coefficients in rats exposed to cyfluthrin(P all>0.05). The results of HE staining showed that compared with the control group,with the increase of cyfluthrin dose,the renal tubule swelling became more and more obvious,a large number of renal tubular epithelial cells fell off,and the glomeruli atrophied.The results of transmission electron microscope showed that compared with the control group,with the increase of the dose of cyfluthrin,the basement membrane thickened gradually,and the mitochondria and endoplasmic reticulum were damaged in different ways.Compared with the control group,the content of MDA in low,medium and high dose groups increased(P all<0.05),SOD activity decreased(P all<0.05).Compared with the control group,the protein expression levels of GADD45B,p-JNK and p-p38MAPK were increased in low,middle and high dose cyfluthrin groups(P all<0.05),while the protein expression levels of JNK and p38MAPK were decreased in cyfluthrin groups(P all<0.05).Western blot showed that compared with the control group,the mRNA expression levels of GADD45B,p-JNK and p-p38MAPK in the low,middle and high dose groups of cyfluthrin were all increased(P all<0.05),and the mRNA expression levels of JNK and p38MAPK were decreased(P all<0.05).Conclusion GADD45B can induce renal injury in rats by activating the JNK p38MAPK pathway during cyfluthrin induced renal injury.