本文選題：角膜成纖維細(xì)胞 + 機械牽拉�。� 參考：《太原理工大學(xué)》2014年博士論文

【摘要】：繼發(fā)性角膜擴張是LASIK術(shù)后最嚴(yán)重的并發(fā)癥之一,部分病例最終不得不進(jìn)行角膜移植,目前病因尚不清楚。LASIK術(shù)后角膜的應(yīng)力進(jìn)行了重新分布,同時損傷引起各種細(xì)胞因子和生長因子釋放,基質(zhì)細(xì)胞生存的微環(huán)境發(fā)生了變化。因此,本文通過對體外培養(yǎng)的兔角膜成纖維細(xì)胞進(jìn)行力學(xué)加載,著重探討周期性機械牽拉、細(xì)胞因子及炎性因子對角膜成纖維細(xì)胞增殖、遷移及基質(zhì)代謝的影響,從力學(xué)生物學(xué)角度對LASIK術(shù)后角膜損傷修復(fù)及角膜擴張病變發(fā)生和發(fā)展的可能機理進(jìn)行深入研究。 主要工作及研究結(jié)果如下： (1)體外模擬LASIK術(shù)后角膜力學(xué)環(huán)境變化,探討5%周期性牽拉條件下,表皮生長因子(EGF)和堿性成纖維細(xì)胞生長因子(bFGF)對角膜成纖維細(xì)胞增殖、遷移的影響。結(jié)果發(fā)現(xiàn)5%周期性牽拉能夠促進(jìn)角膜成纖維細(xì)胞增殖,但抑制了細(xì)胞遷移行為。EGF和bFGF可以減弱牽拉對細(xì)胞遷移的抑制效應(yīng)。 (2)探討了不同牽拉幅度的機械應(yīng)力對角膜成纖維細(xì)胞基質(zhì)金屬蛋白酶(MMPs)及其抑制因子(TIMPs)、Ⅰ型膠原(Collagen Ⅰ)表達(dá)的影響。 研究發(fā)現(xiàn)：不同幅度周期性牽拉對MMPs、TIMPs和Collagen Ⅰ表達(dá)的調(diào)節(jié)具有雙向性：低幅度牽拉(5%)抑制MMP-2表達(dá),對MT1-MMP無顯著影響,同時促進(jìn)TIMPs和Collagen Ⅰ表達(dá)；高幅度牽拉(15%)則促進(jìn)MMP-2和MT1-MMP表達(dá),抑制TIMPs和Collagen Ⅰ表達(dá)。實驗結(jié)果表明機械牽拉在角膜成纖維細(xì)胞基質(zhì)代謝調(diào)控中發(fā)揮了重要作用。 (3)LASIK術(shù)后的角膜損傷修復(fù)及圓錐角膜常常伴有炎癥的發(fā)生,加之應(yīng)力狀態(tài)的改變,使角膜處于復(fù)雜的環(huán)境中,這些因素對角膜成纖維細(xì)胞基質(zhì)代謝的影響尚不清楚。因此,我們在損傷性牽拉的條件下添加了炎性因子IL-1p,探討炎性因子與機械牽拉聯(lián)合作用對角膜成纖維細(xì)胞MMPs、TIMPs及Collagen Ⅰ表達(dá)的影響。 研究發(fā)現(xiàn)：IL-1p與15%周期性牽拉聯(lián)合作用對角膜成纖維細(xì)胞MMP-1、MMP-3和MMP-9表達(dá)有協(xié)同作用,但對MMP-2無顯著影響TIMP-1顯著下調(diào),TIMP-2無顯著變化；Collagen IalmRNA表達(dá)水平進(jìn)一步下降,兩者具有協(xié)同作用。提示炎癥等因素啟動了一些MMPs表達(dá)后,損傷性周期性牽拉對IL-1β誘導(dǎo)MMPs有放大作用,這將進(jìn)一步增加角膜基質(zhì)降解的風(fēng)險。 (4)ERK1/2信號通路參與了損傷性機械牽拉介導(dǎo)的角膜成纖維細(xì)胞MMP-2的表達(dá)調(diào)控。 我們首先通過MAPK家族信號通路抑制劑篩選了與15%周期性牽拉介導(dǎo)的MMP-2表達(dá)有關(guān)的主要信號通路。實驗結(jié)果發(fā)現(xiàn)PD98059(MEK信號通路抑制劑)能夠顯著抑制機械牽拉引起的MMP-2表達(dá),而SP600125(JNK信號通路抑制劑)和SB203850(p38信號通路抑制劑)則對MMP-2的表達(dá)沒有顯著影響。其次,15%周期性牽拉使ERK1/2磷酸化水平明顯增強,PD98059則使ERK磷酸化水平受到明顯抑制。說明ERK1/2參與了損傷性牽拉引起的MMP-2表達(dá)的調(diào)控。 綜合以上結(jié)論我們得出：角膜成纖維細(xì)胞能夠通過調(diào)節(jié)細(xì)胞的增殖、遷移和基質(zhì)代謝,對不同的機械牽拉幅度做出響應(yīng)。低幅度周期性牽拉(5%)有利于角膜基質(zhì)合成,高幅度周期性牽拉(15%)則可能導(dǎo)致角膜基質(zhì)降解,尤其在炎性因子存在的情況下。
[Abstract]:Secondary corneal dilatation is one of the most serious complications after LASIK, and some cases eventually have to undergo corneal transplantation. At present, it is not clear that the stress of the cornea is redistributed after.LASIK, and the damage causes the release of various cytokines and growth factors, and the microenvironment of the survival of the stromal cells has changed. The effects of periodic mechanical pull, cytokines and inflammatory factors on the proliferation, migration and matrix metabolism of corneal fibroblasts were investigated by mechanical loading of rabbit corneal fibroblasts cultured in vitro. The possible mechanism of corneal injury repair and development and development of corneal dilatation after LASIK was studied from the mechanical and biological point of view. Carry out an in-depth study.
The main work and research results are as follows:
(1) the changes of corneal mechanical environment after LASIK were simulated in vitro. The effects of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on the proliferation and migration of corneal fibroblasts were investigated under 5% periodic stretch conditions. The results showed that 5% periodic traction could promote the proliferation of corneal fibroblasts, but inhibited the cell migration behavior of.EGF. And bFGF can attenuate the inhibitory effect of stretch on cell migration.
(2) the effects of mechanical stress on the expression of matrix metalloproteinase (MMPs) and its inhibitory factor (TIMPs) and type I collagen (Collagen I) in corneal fibroblasts were investigated.
The study found that the regulation of MMPs, TIMPs and Collagen I expression of different amplitude periodicity is bidirectional: low amplitude traction (5%) inhibits MMP-2 expression, has no significant effect on MT1-MMP, and promotes the expression of TIMPs and Collagen I; high amplitude traction (15%) promotes the expression of MMP-2 and MT1-MMP, and inhibits TIMPs and Collagen I expression. The results showed that mechanical traction played an important role in the regulation of matrix metabolism in corneal fibroblasts.
(3) the repair of corneal injury after LASIK and the occurrence of keratoconus often accompanied by inflammation, and the change of stress state, the cornea is in a complex environment, and the influence of these factors on the matrix metabolism of corneal fibroblasts is not clear. Therefore, we add the inflammatory factor IL-1p to the inflammatory factors under the condition of damaged traction. The effect of combined mechanical traction on the expression of MMPs, TIMPs and Collagen I in corneal fibroblasts.
It was found that the combined effect of IL-1p and 15% periodic traction had synergistic effect on the expression of MMP-1, MMP-3 and MMP-9 in corneal fibroblasts, but there was no significant effect on TIMP-1, TIMP-2 had no significant change in MMP-2, and the IalmRNA expression level of Collagen decreased further, and both had synergism. Some MMPs tables were initiated by the inflammatory factors. After injury, traumatic periodic stretch has an amplification effect on IL-1 beta induced MMPs, which will further increase the risk of corneal matrix degradation.
(4) ERK1/2 signaling pathway is involved in the regulation of MMP-2 expression in injured mechanical dragging corneal fibroblasts.
We first screened the main signaling pathways associated with the 15% periodic traction mediated MMP-2 expression through the MAPK family signal pathway inhibitors. The results showed that the PD98059 (MEK signaling pathway inhibitor) could significantly inhibit the MMP-2 expression induced by mechanical pull, while SP600125 (JNK signaling pathway inhibitor) and SB203850 (p38 signaling pathway inhibition) However, there was no significant effect on the expression of MMP-2. Secondly, 15% periodic traction increased the level of phosphorylation of ERK1/2 significantly, while PD98059 significantly inhibited the level of ERK phosphorylation. It indicated that ERK1/2 was involved in the regulation of MMP-2 expression induced by damaged traction.
We conclude that corneal fibroblasts can respond to different mechanical pull ranges by regulating cell proliferation, migration and matrix metabolism. Low amplitude periodic traction (5%) is beneficial to corneal stroma synthesis, and high periodic stretch (15%) may lead to corneal stroma degradation, especially in the presence of inflammatory factors. Under the circumstances.
【學(xué)位授予單位】：太原理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：R772.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前5條

1 曹志杰,王勤美;近視LASIK術(shù)后角膜膨隆的研究進(jìn)展[J];國際眼科雜志;2004年06期

2 趙長霖;彭琦;謝漢平;;ECM,MMP與角膜結(jié)構(gòu)和角膜損傷修復(fù)[J];國際眼科雜志;2006年01期

3 謝毅;樊瑜波;鄧應(yīng)平;孫曉萍;吳凌;鄒遠(yuǎn)文;黃學(xué)進(jìn);;兔眼準(zhǔn)分子激光原位角膜磨鑲術(shù)后角膜擴張的研究[J];生物醫(yī)學(xué)工程研究;2008年01期

4 潘紅衛(wèi);李學(xué)晶;徐錦堂;陳妙姣;馬榮;;角膜基質(zhì)細(xì)胞的表型轉(zhuǎn)化及其分子機制[J];中國病理生理雜志;2011年04期

5 汪曉瑜;陳世豪;王勤美;黃錦海;;正常角膜、亞臨床圓錐角膜及圓錐角膜角膜生物力學(xué)的臨床研究[J];醫(yī)學(xué)研究雜志;2010年08期

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