本文選題：促紅細(xì)胞生成素　切入點(diǎn)：缺血性心臟病　出處：《福建醫(yī)科大學(xué)》2008年博士論文　論文類型：學(xué)位論文

【摘要】： 背景動(dòng)脈粥樣硬化性疾病的一、二級預(yù)防已經(jīng)使缺血性心臟病事件的發(fā)生率顯著下降。但是缺血性心臟病依然是大多數(shù)發(fā)達(dá)國家最主要的死亡病因之一。為了進(jìn)一步減少急性缺血性心臟病事件的發(fā)生率,人們?nèi)栽趯ふ腋鞣N更為有效的治療方案。促紅細(xì)胞生成素(erythropoietin, Epo)是由165個(gè)氨基酸組成并折疊成4個(gè)α螺旋的糖蛋白。屬于I型細(xì)胞因子超家族,分子量約為30.4kDa。Epo最早運(yùn)用于慢性腎功能衰竭相關(guān)性貧血治療。此后Bernaudin等發(fā)現(xiàn)其在腦缺血及神經(jīng)組織的機(jī)械性損傷中也發(fā)揮著保護(hù)作用,多項(xiàng)實(shí)驗(yàn)表明,腦組織局部及全身運(yùn)用Epo可防治缺血誘發(fā)的神經(jīng)元損傷。相似的,通過動(dòng)物模型人們逐漸認(rèn)識(shí)到Epo的心肌保護(hù)作用。近年來有部分小規(guī)模臨床實(shí)驗(yàn)提示了Epo的心肌保護(hù)效應(yīng),但是其具體分子生物學(xué)機(jī)制尚未闡明。 目的為了深入探討Epo在缺血性心臟病中的生理保護(hù)作用及其臨床意義。明確:1、Epo治療是否能影響心肌細(xì)胞凋亡;2、促進(jìn)血管新生、改善心肌梗塞術(shù)后心功能;3、明確EPO在缺血再灌注損傷中的保護(hù)機(jī)制,我們設(shè)計(jì)了該課題。 方法 1、通過RT-PCR及Western Blot驗(yàn)證體外培養(yǎng)的心肌細(xì)胞是否表達(dá)Epo的受體。采用H_2O_2誘導(dǎo)體外培養(yǎng)心肌細(xì)胞凋亡,運(yùn)用Tunel染色探討Epo對H_2O_2誘導(dǎo)的心肌細(xì)胞凋亡的影響。結(jié)合細(xì)胞信號傳導(dǎo)通路阻滯劑明確Epo抑制心肌細(xì)胞凋亡的信號傳導(dǎo)通路。分別收集不同時(shí)間點(diǎn)的心肌細(xì)胞培養(yǎng)上清液,觀測Epo對心肌細(xì)胞VEGF表達(dá)的影響。 2、采用Langendroff離體心臟缺血再灌注模型,運(yùn)用不同劑量Epo觀測Epo對缺血再灌注離體心臟的血流動(dòng)力學(xué)影響;OCT染色觀測Epo對梗塞面積的調(diào)節(jié)。結(jié)合信號傳導(dǎo)通路阻滯劑,探討Epo對細(xì)胞外基質(zhì)代謝的調(diào)節(jié)作用及其機(jī)制。酶譜法(Zymography Assay)及大鼠缺血再灌注模型驗(yàn)證EPO對缺血再灌注損傷后MMPs活性的調(diào)節(jié)。 結(jié)果證實(shí)心肌細(xì)胞表達(dá)Epo受體;Epo可抑制H_2O_2誘導(dǎo)的心肌細(xì)胞凋亡、下調(diào)心肌細(xì)胞促凋亡相關(guān)蛋白的表達(dá),上調(diào)抗凋亡蛋白表達(dá)。Epo通過Erk及PI3K-Akt途徑抑制細(xì)胞凋亡。Epo可促進(jìn)心肌細(xì)胞VEGF的表達(dá)及內(nèi)皮細(xì)胞增殖;通過促進(jìn)心肌細(xì)胞分泌VEGF,EPO可間接對內(nèi)皮細(xì)胞的增殖發(fā)生調(diào)控。利用Langendroff離體心臟缺血再灌注模型,運(yùn)用不同劑量Epo證實(shí)Epo可改善缺血再灌注離體心臟的血流動(dòng)力學(xué)指標(biāo);減少缺血再灌注損傷后梗塞面積。Epo激活了Jak2-Erk信號傳導(dǎo)通路,促進(jìn)了CollagenI/III的表達(dá),抑制了MMP2及MMP9的表達(dá)。MEK拮抗劑可抑制Epo的這一保護(hù)作用。在1周的隨訪期中EPO顯著抑制了心肌缺血再灌注損傷后MMPs的活性。 結(jié)論 1、心肌細(xì)胞可表達(dá)EPO的受體,EPO經(jīng)由Erk及Akt途徑抑制心肌細(xì)胞凋亡; 2、EPO促進(jìn)心肌細(xì)胞VEGF的合成分泌,促進(jìn)內(nèi)皮細(xì)胞增殖; 3、EPO治療可顯著提高心肌梗塞術(shù)后小鼠的生存率、改善心功能、抑制心臟組織凋亡、促進(jìn)血管新生。 4、EPO可通過Erk途徑調(diào)節(jié)心臟組織細(xì)胞外基質(zhì)代謝。
[Abstract]:The background of atherosclerotic disease, two grade prevention has made the incidence of ischemic heart disease events decreased significantly. But ischemic heart disease is still one of the main causes of death in most developed countries. In order to further reduce the events of acute ischemic heart disease incidence, people are still looking for more effective treatments for erythropoietin. Erythropoietin (erythropoietin, Epo) is composed of 165 amino acids and 4 alpha helices folded into glycoproteins. Type I cytokine superfamily, a molecular weight of about 30.4kDa.Epo was first used in the treatment of chronic renal failure associated with anemia. Then Bernaudin found to play in cerebral ischemia and neural tissue machine injury protection, a number of experiments showed that the neuronal damage in brain tissue of local and systemic use of Epo can prevent ischemia induced by animals. Similar. Models have gradually recognized the protective effect of Epo on myocardium. In recent years, some small-scale clinical trials have suggested the myocardial protective effect of Epo, but the specific molecular biological mechanisms have not yet been elucidated.
Objective to investigate the physiological protective effect of Epo in ischemic heart disease and its clinical significance. Clear: 1, Epo treatment can influence the apoptosis of myocardial cells; 2, promote angiogenesis and improve cardiac function after myocardial infarction; 3, clear EPO in ischemia reperfusion injury protection mechanism, we designed this topic.
Method
1, whether through RT-PCR and Western Blot to verify the in vitro cultured myocardial cells. The expression of Epo receptor induced by H_2O_2 cultured myocardial cells apoptosis in vitro, the use of Tunel to explore the effects of Epo on myocardial cell apoptosis induced by H_2O_2 staining. The signal transduction pathway combined with cell signaling pathway blocker clear Epo inhibition of myocardial cell apoptosis were collected from different. At the time of the myocardial cell culture supernatant, observing the effects of Epo on the expression of VEGF in myocardial cell.
2, using Langendroff isolated heart ischemia reperfusion model with different doses of Epo Epo observation on ischemia reperfusion hemodynamics from body cardiac effects; OCT staining observation of Epo regulation on infarction area. Combined with the signal transduction pathway blocker, to investigate the regulatory effect of Epo on extracellular matrix metabolism enzymes (method and its mechanism. Zymography Assay) and the regulation of ischemia reperfusion rat model validation EPO on ischemia reperfusion injury of MMPs activity.
The results confirmed that the expression of Epo receptor in myocardial cells; myocardial Epo can inhibit cell apoptosis induced by H_2O_2, expression of myocardial cell apoptosis related protein, up regulation of anti apoptotic protein.Epo expression through Erk and PI3K-Akt pathway to inhibit apoptosis and expression of.Epo can promote the proliferation of endothelial cells of myocardial cell VEGF; myocardial cells by promoting the secretion of VEGF, EPO the indirect control of the proliferation of endothelial cells. Using Langendroff isolated heart ischemia reperfusion model with different doses of Epo showed that Epo can improve the hemodynamics index from ischemia reperfusion cardiac ischemia reperfusion injury; reduce infarct volume after.Epo activation of the Jak2-Erk signaling pathway, promote the expression of CollagenI/III, this protective effect inhibited the expression of.MEK antagonist MMP2 and MMP9 inhibited Epo. During the follow-up period of 1 weeks in EPO significantly inhibited the myocardial ischemia reperfusion The activity of MMPs after injury.
conclusion
1, cardiac myocytes can express EPO receptor, and EPO inhibits cardiomyocyte apoptosis via Erk and Akt pathway.
2, EPO promotes the synthesis and secretion of VEGF in cardiac myocytes and promotes the proliferation of endothelial cells.
3, EPO therapy can significantly improve the survival rate of mice after myocardial infarction, improve cardiac function, inhibit cardiac apoptosis and promote angiogenesis.
4, EPO can regulate the metabolism of extracellular matrix in the cardiac tissue by Erk pathway.

【學(xué)位授予單位】：福建醫(yī)科大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2008
【分類號】：R-332;R54

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 王小雯;促紅細(xì)胞生成素及其受體對實(shí)驗(yàn)性急性心肌梗死大鼠的心肌保護(hù)作用[D];吉林大學(xué);2009年

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本文編號：1626040