本文選題：�；撬�　切入點：As_2O_3　出處：《大連醫(yī)科大學》2017年碩士論文

【摘要】：目的:砷是存在于自然界中的環(huán)境污染物之一。無機砷的暴露會引起很多慢性疾病的發(fā)生,比如糖尿病。而母體的高砷暴露對子代的影響更是引起了越來越多的關(guān)注。自噬是通過清除失調(diào)線粒體更新線粒體生物源,通過線粒體伴侶分子及線粒體水解酶管理線粒體蛋白質(zhì)量,從而達到健康線粒體數(shù)量的平衡的過程,然而自噬的失調(diào)會造成組織損傷,引起相關(guān)疾病。有研究表明,活性氧(ROS)的產(chǎn)生與砷引起的胰島素抵抗及糖尿病有很大關(guān)系。而轉(zhuǎn)錄因子NF-E2相關(guān)因子(Nrf2)是細胞氧化應(yīng)激反應(yīng)中的關(guān)鍵因子,具有抗氧化作用,與機體的防御系統(tǒng)密切相關(guān)。本課題組已有研究證明砷可以引起大鼠肝臟的自噬性死亡,但其機制是否與Nrf2和Trx有關(guān)還需進一步研究。�；撬崾翘烊淮嬖谟谧匀唤缰械目寡趸镔|(zhì),但是否可以緩解砷誘導(dǎo)的胰腺損傷及其機制還不清楚。因此,本研究擬探討�；撬峥煞裢ㄟ^Nrf2-Trx通路干預(yù)砷引起的子代大鼠胰腺的自噬性損傷。方法:本實驗以Wistar大鼠為研究對象,孕鼠暴露于濃度為2 mg/kg BW~8mg/kg BW的三氧化二砷(As_2O_3),及150 mg/kg BW濃度�；撬峁辔负�,進行8mg/kg BW As_2O_3灌胃,至子代斷乳,后將子代大鼠繼續(xù)暴露于與母鼠相同劑量的As_2O_3至性成熟,共57天。對子代大鼠胰腺進行蘇木精-伊紅(HE)染色,觀察子代大鼠胰腺的形態(tài);用電子顯微鏡觀察子代大鼠胰腺細胞中自噬體的形成情況,計數(shù);用蛋白質(zhì)印跡法(Western blot)檢測子代大鼠胰腺中Nrf2蛋白及自噬生物標記物LC3蛋白的表達情況;用RT-PCR方法檢測子代大鼠胰腺中Trx基因的表達情況;利用MDA試劑盒測量胰腺組織中MDA的水平。結(jié)果:HE染色結(jié)果顯示,隨著As_2O_3濃度的增加,子代大鼠胰腺細胞及胰島明顯縮小,而在�；撬岜Ｗo組,子代大鼠胰腺細胞形態(tài)未見明顯異常;電子顯微鏡下可見,As_2O_3暴露后,子代大鼠胰腺中有自噬體形成,其數(shù)量隨著As_2O_3濃度的升高而增多,牛磺酸保護組自噬體增多不明顯;子代大鼠胰腺中LC3-II蛋白表達隨著As_2O_3濃度的升高而增加,�；撬岜Ｗo組LC3-II蛋白表達較8mg/kg BW As_2O_3暴露組LC3-II蛋白的表達量減少;子代大鼠胰腺中Nrf2蛋白,Trx基因及MDA的水平隨著As_2O_3暴露劑量的升高而明顯減少,而在牛磺酸保護組,其表達量較8 mg/kg BW As_2O_3暴露組蛋白表達量明顯上升。結(jié)論:As_2O_3可引起的子代大鼠胰腺自噬性損傷;Nrf2-Trx的抑制造成As_2O_3引起的子代大鼠胰腺自噬性損傷;牛磺酸可通過激活Nrf2-Trx通路干預(yù)As_2O_3引起的子代大鼠胰腺自噬性損傷。
[Abstract]:Objective: arsenic is one of the environmental pollutants in nature.Exposure to inorganic arsenic can cause many chronic diseases, such as diabetes.More and more attention has been paid to the effects of high arsenic exposure on offspring.Autophagy is the process of renewing mitochondrial biological sources by clearing out dysfunctional mitochondria and managing mitochondrial protein content through mitochondrial chaperones and mitochondrial hydrolases, thus achieving a healthy mitochondrial balance.However, autophagy disorders can cause tissue damage, causing related diseases.Studies have shown that reactive oxygen species (Ros) production is associated with arsenic-induced insulin resistance and diabetes.The transcription factor NF-E2 related factor Nrf2 is a key factor in the oxidative stress response of cells. It has antioxidant effect and is closely related to the body's defense system.Our research has shown that arsenic can induce autophagic death in rat liver, but whether the mechanism is related to Nrf2 and Trx needs further study.Taurine is a natural antioxidant in nature, but it is not clear whether it can alleviate arsenic induced pancreatic injury and its mechanism.Therefore, the aim of this study was to investigate whether taurine could interfere with arsenic induced autophagy injury in rat pancreas via Nrf2-Trx pathway.Methods: in this experiment, Wistar rats were exposed to 2 mg/kg BW~8mg/kg BW arsenic trioxide (as _ 2O _ 2O _ 3) and 150 mg/kg BW taurine. After the rats were fed with 8mg/kg BW As_2O_3, the rats were fed with 8mg/kg BW As_2O_3 and then weaned in their offspring.Then the offspring rats were exposed to the same dose of As_2O_3 as the mother rat until sexual maturation for 57 days.The morphology of rat pancreas was observed by hematoxylin-eosin-hehe staining and the formation and count of autophagy in pancreatic cells of offspring rats were observed by electron microscope.The expression of Nrf2 protein and autophagy biomarker LC3 protein in rat pancreas was detected by Western blotting, and the expression of Trx gene was detected by RT-PCR method.The level of MDA in pancreatic tissue was measured by MDA kit.Results with the increase of As_2O_3 concentration, the pancreatic cells and islets of the offspring decreased significantly, but in the taurine protected group, the morphology of pancreatic cells in the offspring was not significantly abnormal, and that after the exposure of as _ 2O _ 3 was observed under the electron microscope.Autophagy was formed in the pancreas of offspring rats, and the number of autophagy increased with the increase of As_2O_3 concentration, but the increase of autophagy in taurine protected group was not obvious, and the expression of LC3-II protein in pancreas of offspring rats increased with the increase of As_2O_3 concentration.The expression of LC3-II protein in taurine protected group was lower than that in 8mg/kg BW As_2O_3 group, and the level of Nrf2 protein Trx gene and MDA in the pancreas of offspring decreased with the increase of As_2O_3 exposure dose, but in taurine protective group.The expression of histone was significantly higher than that of 8 mg/kg BW As_2O_3.Conclusion the inhibition of Nrf2-Trx in the pancreatic autophagy of offspring rats induced by% As2O3 can result in autophagy injury induced by As_2O_3, and taurine can interfere with the pancreatic autophagy injury induced by As_2O_3 by activating the Nrf2-Trx pathway.
【學位授予單位】：大連醫(yī)科大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：R114

【參考文獻】

相關(guān)期刊論文 前1條

1 David J.Thomas;Karen Bradham;;Role of complex organic arsenicals in food in aggregate exposure to arsenic[J];Journal of Environmental Sciences;2016年11期

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本文編號：1711314