2012-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/644422摘要：長期腹膜透析因為使用非生理性的透析液中，因而會造成腹膜膜結構的改變。這個獨特的病理現象是增厚的腹膜，由密集膠原纖維沉積組成。腹膜的厚度增加隨透析時間延長更加明顯。腹膜纖維化會導致失超過濾失效，甚至引起嚴重的包膜性腹膜硬化症。明確的發病機制仍不清楚，但幾個生長因子與發炎細胞素應與腹膜纖維化有關。人體血液中有一個脂質分子Lysophosphatidic acid (LPA)，有很多生理作用。LPA是可以由人類腹膜間皮細胞持續分泌出來。它可促進細胞組織修復，促進細胞生長、增殖、分化、移動，並可以延長細胞生存。此外，LPA 也可以透過其受體LPA1和結締組織生長素 (CTGF）誘發合成膠原纖維有相關。此外LPA也可以促進發炎性細胞素的製造及分泌，並經由這些細胞素來刺激轉化生長因數(TGF)分泌及接下來的的細胞外基質產生。這在整個腹膜纖維化的病理機轉，LPA也許提供了比發炎性細胞素更上游的更多資訊。在我們初步的資料中人類腹膜間皮細胞會製造並分泌LPA並促進CTGF基因的合成，所以研究LPA在人類腹膜間皮細胞的影響是合適的。有一個LPA1拮抗劑Ki16425可以阻斷LPA1作用的下游路徑。Ki16425將用於在實驗中測試 LPA 的作用。它也是提供治療腹膜纖維化的一種選擇。第一年將會進行人類腹膜間皮細胞的實驗研究。不同濃度的葡萄糖及非生理性的透析液將用來刺激LPA分泌。我們將會了解LPA對於腹膜纖維化的影響。Ki16425將會加到細胞實驗中，來測試它們抗纖維化的功用。這也可以提往後治療包膜性腹膜硬化症的藥理基礎。第二年將會進行到了體內的大鼠透析液腹腔注射的實驗。測量經由4.25%的透析液刺激大鼠腹膜LPA分泌。此外LPA1的表現會由定量polymerase chainreaction和免疫螢光染色來分析。腹膜纖維化基因表現程度的分析，包括CTGF，第一型膠原蛋白和TGF都會加以測量分析。Ki16425也會加以研究是否可以減少這些腹膜纖維化基因表現程度。作為治療的動物實驗基礎。第三年將直接以病患的透析流出液做為分析的檢體。病患進行年度腹膜平衡試驗以及發生腹膜炎發時，患者的腹膜透析流出液將收集來測量LPA濃度。這些濃度將與其他分子包括TG-Fbeta、白細胞介素 6、玻尿酸，和CA125以及其他臨床特徵加以比較。非生理性透析液的刺激纖維化基因的表現，LPA的拮抗劑是一個極可能的治療藥物，本研究將從細胞層面、大鼠模式及病患本身一步一步來釐清LPA在腹膜透析患者的角色。<br> Abstract: Long-term peritoneal dialysis (PD) is associated with alterations in the structure ofperitoneal membrane resulted from unphysiological dialysate. The unique pathologicalfinding is thickened submesothelial zone which composed with dense collagen deposition.The thickness of submesothelial zone increased with prolonged PD duration. The peritonealfibrosis (PF) would lead to ultrafiltration failure and even catastrophic encapsulatingperitoneal sclerosis (EPS). The definite pathogenesis remain unclear but several growthfactors and inflammatory cytokines will be associated with PF.Lysophosphatidic acid (LPA) is present in the human blood and owns many functions.LPA is also constitutively produced by human peritoneal mesothelial cells. It can enhancewound repair and tissue development by promoting cell growth, proliferation, differentiation,motility, and survival. In addition, LPA is also associated with fibrosis through LPA1 receptorand the following connective tissue growth factors (CTGF) production. LPA can alsoupregulate inflammatory cytokines therefore induce transforming growth factor (TGF)secretion, and the following extracellular matrix production. This is the whole pathogenesisprocess of PF and LPA provide more upstream information prior to inflammatory cytokinessecretion.In our preliminary data, LPA will induce CTGF mRNA synthesis in human peritonealmesothelial cell (HPMC), the effects of LPA might be appropriate for the HPMC. There is aLPA1 antagonist Ki16425 which could suppress the LPA1 downstream pathway. Ki16425will be used to test the role of LPA in experiments. It is also provide a treatment option inperitoneal fibrosis.In the first year, in vitro study with HPMC will be conducted. Secretion of LPAstimulated with unphysiologic dialysate and glucose concentration will be tested. Thefibrogenic effect of LPA will be elucidated. Ki16425 will be added to test there antifibroticeffects. In the second year, the study will be continued into an in vivo rat dialysate infusionmodel. The secretion of LPA will be measured. The LPA1 expression on the peritoneum willbe analyzed with qPCR and immunochemical stain. The fibrosis induced by the 4.25 %dialysate will be analyzed with microscopy and fibrogenic genes expression including CTGF,collagen I, and TGF-beta. In the third year, effluent of PD patients in peritoneal equilibrationtest and peritonitis episode will be collected to measure LPA concentration. Theseconcentrations will be compared to other molecules including TGF beta, interleukin 6,hyaluronan, and CA 125 as well as clinical characteristics.After completing these studies, the role of LPA in PD patients will be clarified.Stimulated by unphysiologic dialysate, fibrogenic potential, secretion during peritonitis andthe impact on clinical characterisitics are all included in these studies.腹膜透析腹膜纖維化Lysophosphatidic acidKi16425Ki16425Lysophosphatidic acidperitoneal dialysisperitoneal fibrosis