【摘要】：目的：研究天然物質(zhì)蒜素是否能保護(hù)人視網(wǎng)膜色素上皮細(xì)胞(ARPE-19)免受過氧化氫(H2O2)-誘導(dǎo)損傷,并確定蒜素對(duì)過氧化氫誘導(dǎo)的氧化應(yīng)激損傷的人視網(wǎng)膜色素上皮細(xì)胞(ARPE-19)的影響和潛在分子機(jī)制。為年齡相關(guān)性黃斑變性等與氧化應(yīng)激相關(guān)的眼病防治研究方面提供實(shí)驗(yàn)室證據(jù)。方法：1.ARPE-19細(xì)胞暴露在250μM或500μM過氧化氫內(nèi)12或24小時(shí),后培養(yǎng)在預(yù)先備好的各種濃度的蒜素內(nèi)(0、5、10、20或40μg／毫升)4 h。RPEs的活力使用MTT試驗(yàn)評(píng)估。確定蒜素對(duì)過氧化氫誘導(dǎo)ARPE-19細(xì)胞的影響。2.對(duì)濃度梯度的蒜素預(yù)處理的ARPE-19細(xì)胞進(jìn)行250μM過氧化氫誘導(dǎo)后通過2、7'-二氯熒光乙酰乙酸鈉(DCFH-DA)熒光探針檢測(cè)細(xì)胞內(nèi)活性氧(ROS)的生成,比色法檢測(cè)細(xì)胞內(nèi)ROS、谷胱甘肽(GSH)/二硫化谷胱甘肽(GSSG)比值和丙二醛(MDA)的水平,確定蒜素對(duì)ARPE-19細(xì)胞過氧化氫誘導(dǎo)損傷的影響。3.濃度梯度的蒜素預(yù)處理的ARPE-19細(xì)胞進(jìn)行250μM濃度過氧化氫誘導(dǎo)的氧化應(yīng)激狀態(tài)下通過熒光定量PCR檢測(cè)和蛋白質(zhì)印跡檢測(cè)ARPE-19細(xì)胞核蛋白質(zhì)mRNA,核蛋白NOX4,NQO1及Nrf2表達(dá)水平。進(jìn)一步確定蒜素保護(hù)視網(wǎng)膜色素上皮細(xì)胞免受氧化應(yīng)激損傷的潛在機(jī)制。4.濃度梯度的蒜素預(yù)處理的ARPE-19細(xì)胞進(jìn)行250μM濃度過氧化氫誘導(dǎo)的氧化應(yīng)激狀態(tài)下通過基因轉(zhuǎn)染方法對(duì)Nrf2基因進(jìn)行干涉,進(jìn)一步應(yīng)用熒光定量PCR檢測(cè)法、蛋白質(zhì)印跡檢測(cè)法、MTT法等檢測(cè)ARPE-19細(xì)胞核蛋白質(zhì)和胞漿蛋白質(zhì)內(nèi)Nrf2相關(guān)mRNA表達(dá)水平、Nrf2蛋白質(zhì)表達(dá)水平,評(píng)估Nrf2抑制效率、比較各組間生存力的差異,確定Nrf2在蒜素保護(hù)RPEs在H202誘導(dǎo)損傷機(jī)制中的調(diào)節(jié)效應(yīng)。結(jié)果：1.ARPE-19細(xì)胞暴露于過氧化氫內(nèi)處理12或24小時(shí)后導(dǎo)致細(xì)胞生存能力顯著損失。蒜素可以逆轉(zhuǎn)RPEs被過氧化氫的損傷效應(yīng),此現(xiàn)象是劑量依賴性的。2.在ARPE-19細(xì)胞內(nèi),蒜素通過減少細(xì)胞內(nèi)的ROS、MDA的水平和增加GSH/GSSG來減弱H202-誘導(dǎo)的氧化應(yīng)激反應(yīng)。3.蒜素保護(hù)過氧化氫誘導(dǎo)的視網(wǎng)膜色素上皮細(xì)胞(ARPE-19 cells)的潛在機(jī)制可能是通過調(diào)節(jié)ROS-相關(guān)酶的表達(dá)水平,包括SOD、NOX4、NQO1以及Nrf2。4.蒜素介導(dǎo)的過氧化氫一誘導(dǎo)損傷的保護(hù)作用與Nrf2的調(diào)節(jié)有關(guān)。蒜素通過劑量-依賴的方式增強(qiáng)Nrf2相關(guān)的mRNA的表達(dá)水平。抑制Nrf2可顯著減弱蒜素對(duì)過氧化氫-誘導(dǎo)的細(xì)胞的保護(hù)作用。然而,抑制Nrf2并不能完全抑制蒜素的保護(hù)作用。結(jié)論：1.外源性H202可誘導(dǎo)人視網(wǎng)膜色素上皮細(xì)胞ARPE-19細(xì)胞發(fā)生氧化應(yīng)激損傷。蒜素可以保護(hù)視網(wǎng)膜色素上皮細(xì)胞免受氧化應(yīng)激損傷,此保護(hù)作用是劑量依賴性的。2.蒜素通過調(diào)節(jié)細(xì)胞內(nèi)ROS水平、GSH/GSSG、MDA及SOD等實(shí)現(xiàn)對(duì)視網(wǎng)膜色素上皮細(xì)胞的保護(hù)作用的。3.蒜素保護(hù)視網(wǎng)膜色素上皮細(xì)胞免受氧化應(yīng)激損傷的潛在的機(jī)制可能是通過調(diào)節(jié)ROS相關(guān)酶SOD、NOX4、NQO1以及Nrf2等的表達(dá)實(shí)現(xiàn)的。
[Abstract]:Objective: to study whether allicin can protect human retinal pigment epithelial cells (ARPE-19) from hydrogen peroxide (H2O2)-induced injury. The effect and potential molecular mechanism of allicin on human retinal pigment epithelial cells (ARPE-19) induced by hydrogen peroxide were determined. To provide laboratory evidence for the prevention and treatment of age-related macular degeneration and other eye diseases related to oxidative stress. Methods: 1.ARPE-19 cells were exposed to 250 渭 M or 500 渭 M hydrogen peroxide for 12 or 24 hours, and then cultured in various concentrations of allicin (0, 5, 10, 20 or 40 渭 g / ml) 4 h.RPEs activity was evaluated by MTT test. To determine the effect of allicin on ARPE-19 cells induced by hydrogen peroxide. 2. After 250 渭 M hydrogen peroxide induction of ARPE-19 cells pretreated with allicin, the production of reactive oxygen species (ROS) and intracellular ROS, were detected by 2,7 and dichlorofluorescent sodium acetoacetate (DCFH-DA) fluorescence probe, and the intracellular ROS, was detected by colorimetric assay. The ratio of glutathione (GSH) / disulfide (GSSG) and the level of malondialdehyde (MDA) were determined to determine the effect of allicin on hydrogen peroxide induced damage in ARPE-19 cells. 3. The expression of nuclear protein mRNA, nuclear protein NOX4,NQO1 and Nrf2 in ARPE-19 cells pretreated with allicin was detected by fluorescence quantitative PCR and Western imprinting under 250 渭 M hydrogen peroxide induced oxidative stress. To further determine the potential mechanism of allicin in protecting retinal pigment epithelial cells from oxidative stress. 4. ARPE-19 cells pretreated with allicin were interfered with Nrf2 gene by gene transfer under 250 渭 M hydrogen peroxide induced oxidative stress. Fluorescence quantitative PCR assay and Western imprinting method were further used. MTT assay was used to detect the expression of Nrf2-related mRNA and Nrf2 protein in nuclear protein and cytoplasmic protein of ARPE-19, to evaluate the inhibitory efficiency of Nrf2, and to compare the difference of survivability among the three groups. To determine the regulatory effect of Nrf2 on the mechanism of allicin protective RPEs in H 202 induced injury. Results: the survival ability of 1.ARPE-19 cells was significantly lost after exposure to hydrogen peroxide for 12 or 24 hours. Allicin can reverse the damage effect of RPEs by hydrogen peroxide in a dose-dependent manner. 2. In ARPE-19 cells, allicin attenuated H202-induced oxidative stress by reducing the level of ROS,MDA and increasing GSH/GSSG. The potential mechanism of allicin in protecting retinal pigment epithelial cells (ARPE-19 cells) induced by hydrogen peroxide may be through the regulation of the expression of ROS- related enzymes, including SOD,NOX4,NQO1 and Nrf2.4.. The protective effect of allicin mediated hydrogen peroxide induced injury is related to the regulation of Nrf2. Allicin enhances the expression of Nrf2-related mRNA in a dose-dependent manner. Inhibition of Nrf2 significantly attenuated the protective effect of allicin on hydrogen peroxide-induced cells. However, inhibition of Nrf2 could not completely inhibit the protective effect of allicin. Conclusion: 1. Exogenous H 202 could induce oxidative stress damage in human retinal pigment epithelial cells ARPE-19 cells. Allicin can protect retinal pigment epithelial cells from oxidative stress in a dose-dependent manner. 2. Allicin can protect retinal pigment epithelial cells by regulating intracellular ROS level, GSH/GSSG,MDA and SOD. The potential mechanism of allicin to protect retinal pigment epithelial cells from oxidative stress may be achieved by regulating the expression of ROS related enzymes SOD,NOX4,NQO1 and Nrf2.
【學(xué)位授予單位】：武漢大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：R774.5

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相關(guān)期刊論文 前1條

1 向艷芳;彭惠;;氧化應(yīng)激及補(bǔ)體在年齡相關(guān)性黃斑變性發(fā)病中的作用機(jī)制[J];國(guó)際眼科雜志;2013年08期

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本文編號(hào)：2494602