Investigation of the mechanism of paraquat toxicity -Identification of the genes which are breakthrough for the toxicity-

我们检测了基因表达水平，以了解百草枯（PQ）驱动中毒的机制，得到了以下结果。1)我们检测了PQ对给药16 h后肺抗氧化酶（AOE）基因表达水平和谷胱甘肽（GSH）状态的影响。虽然GSH水平和一些AOE表达水平升高，但GSH没有发挥OH自由基清除剂的作用，因为GSH过氧化物酶（GPX）没有受到刺激。2)一些与氧化应激相关的基因，如硫氧还蛋白、谷胱甘肽s转移酶、血红素氧合酶1（HO-1）、nadph氧化还原酶1（NQO-1）在给药后3 h的RNA表达显著升高。免疫组化分析显示，HO-1和NQO-1在pq处理的肺切片支气管上皮细胞中表达明显。此外，雌性肝脏中一些特异性或显性CYPs的表达水平明显下降，而雄性特异性CYPs的表达水平则有所增加或无影响。更多.3)注射后3 h，肾脏中一些基因的表达水平有所增加，其中金属硫蛋白-1 （MT-1）和HO-1的表达幅度最大。然而，直到注射后24 h才继续增加，第二次注射的效果不如第一次注射。这些RNA水平的上调在蛋白质水平上得到证实。肾脏中的MT-1在第一次注射时已被消耗。这些结果可以解释PQ摄取引起的损伤。4)通过鼻灌胃PQ溶液建立PQ致肺损伤动物模型。该模型肺损伤的病理进展与PQ中毒患者非常相似。5)使用pq中毒小鼠模型，我们在纤维化尚未完全发展的初始破坏阶段（5天内）检测了45个基因表达水平。一些与炎症和凋亡有关的基因在PQ暴露后1天内增加最多，而与纤维化发生有关的基因在PQ暴露后第5天显著增加，在PQ暴露后6 h和24 h均无显著增加。表面活性剂蛋白、EC-SOD、过氧化氢酶的RNA水平呈时间依赖性降低。少

We examined on gene expression levels to understand the mechanism of paraquat (PQ)-driven poisoning and the following results were obtained.1) We examined the effect of PQ on the gene expression levels of antioxidant enzymes (AOE) and glutathione (GSH) status in lungs 16 h post-administration. Although GSH levels as well as some AOE expression levels were increased, GSH did not play as a OH radical scavenger because GSH peroxidase (GPX) was not stimulated.2) Some genes related to oxidative stress, such as thioredoxin, GSH S-transferase, heme oxygenase 1(HO-1), NADPH-oxidoreductase 1 (NQO-1), showed a significant increase in their RNA expression at 3 h post-administration. Immunohistochemical analysis showed that HO-1 and NQO-1 were especially expressed in the bronchial epithelial cells of PQ-treated lung sections. In addition, the expression levels of some CYPs which are specific or dominant in female liver decreased markedly, while the male-specific CYPs showed an increase or no effec … More t.3) We obtained an increase of some genes in kidneys by 3 h after injection, and metallothionein-1 (MT-1) and HO-1 showed the biggest increase. However, the increases did not continue until 24 h after injection, and the second injection had less effect than the first. Up-regulation of these RNA levels was confirmed at the protein level. The MT-1 in kidneys had been consumed by the first injection. These results may explain the injury observed due to PQ uptake.4) We developed an animal model of PQ-induced lung injury by intranasal instillation of PQ solution. The pathological progression of lung injury in this model was very similar to that of patients suffering from PQ poisoning.5) Using the PQ-poisoned mouse model, we examined 45 gene expression levels at the initial destructive phase (within 5 days) that fibrosis has not completely developed. Some genes involved in inflammation and apoptosis showed the maximum increase within 1 day, while the genes involve in the development of fibrosis were significantly increased on day 5, not at 6 h nor at 24 h after PQ exposure. In addition, the RNA level of surfactant protein, EC-SOD, catalase decreased significantly time dependently. Less