CORNEAL LIPID METABOLISM & THE RESPONSE TO INFLAMMATION

角膜脂质代谢

• 批准号: 2159209
• 负责人: Haydee E.P. Bazan
• 金额: $ 15.4万
• 依托单位: LSU HEALTH SCIENCES CENTER
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-07-01 至 1998-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2159209
• 关键词: antisense nucleic acid; collagenase; cornea ulcer; corneal epithelium; gas chromatography mass spectrometry; gene induction /repression; genetic transcription; high performance liquid chromatography; inflammation; inhibitor /antagonist; laboratory rabbit; lipid metabolism; lipoxygenase; northern blottings; oxidoreductase inhibitor; phospholipase A2; platelet activating factor; protooncogene; receptor; second messengers; transcription factor; wound healing

This proposal is a continuation of our ongoing studies of lipid metabolism, focusing on the action of a lipid mediator: 1-0-alkyl-2- acetyl-glycerophosphocholine (platelet-activating factor, PAF). We have found, in corneal epithelium, that PAF activates the expression of the early genes c-fos and c-jun and then the expression of collagenase type 1, the metalloproteinase that degrades interstitial collagen, a major protein of the corneal stroma. A PAF antagonist blocks this effect. We will test two hypotheses: a) that PAF is involved in the mechanism of corneal remodeling and ulcer formation by acting as a lipid second messenger in the transcriptional activation of c-fos, c-jun and the collagenase l gene, and b) that lipoxygenase metabolites formed by the activation of phospholipase A2 have a modulatory effect on PAF. We propose to investigate the PAF signaling pathway and the role of lipoxygenase metabolites in the transcription of collagenase type 1. PAF antagonists and lipoxygenase inhibitors will be evaluated to determine their sites of action and to correlate their biochemical effects with the clinical evolution of corneal ulcers. Another goal of this proposal is to investigate the PAF receptors in the cornea in order to define the sites of action of PAF antagonists in the gene cascade. Powerful analytical procedures such as high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry will be used. Quantification of specific mRNAs will be accomplished by using Northern blots with storage phosphor-imaging. The results obtained will define the involvement of PAF and lipoxygenase metabolites in corneal remodeling and ulcer formation. The new mechanism of action of PAF also can be important in a number of tissue disorders in which normal control of the degradative activity of collagenase appears to be lost, e.a. rheumatoid arthritis, leading to pathological tissue destruction. The action of antagonists can be useful to define new therapeutic tools for control of collagenase type 1 activity.

该建议是我们正在进行的脂质研究的延续 代谢，重点是脂质介质的作用：1-0-烷基-2-- 乙酰甘油磷酸胆碱（血小板激活因子，PAF）。我们有 在角膜上皮中发现PAF激活了 早期基因c-fos和c-jun，然后是胶原酶1型的表达， 降解间隙胶原蛋白的金属蛋白酶，一种主要蛋白 角膜基质。 PAF拮抗剂阻止了这种效果。我们将测试 两个假设：a）PAF参与角膜机制 通过充当脂质第二使者的重塑和溃疡形成 C-FOS，C-JUN和胶原酶L基因的转录激活， b）通过激活形成的脂氧合酶代谢产物 磷脂酶A2对PAF具有调节作用。我们建议 研究PAF信号通路和脂氧合酶的作用 胶原酶1型的转录中的代谢产物。PAF拮抗剂 将评估脂氧合酶抑制剂，以确定其位置 作用并将其生化作用与临床相关联 角膜溃疡的进化。 该建议的另一个目标是调查PAF受体 角膜是为了定义PAF拮抗剂的作用部位 基因级联。 强大的分析程序，例如高性能 液相色谱（HPLC）和气相色谱 - 质量光谱法将 被使用。特定mRNA的量化将通过使用 带有储存磷光剂的北印迹。获得的结果将 定义PAF和Lipoxygoxyase代谢产物在角膜中的参与 重塑和溃疡形成。 PAF的新作用机理也可能很重要 组织疾病的正常控制对降解活性的正常控制 E.A.胶原酶似乎丢失了类风湿关节炎，导致 病理组织破坏。拮抗剂的作用可能有用 定义用于控制胶原酶类型1的新的治疗工具 活动。