CYP1B1 and Retinopathy of Prematurity

特异性细胞色素P450在血管平滑肌细胞和内皮细胞中的表达。它们的产物对血管功能的关键贡献表明，这些基因在血管内稳态中发挥着重要作用。尽管细胞色素P1B1的缺失影响了小梁网的功能和发育。它在视网膜血管形成和血管生成中的生理作用以前还没有被研究过。我们的初步数据表明，在氧诱导的缺血过程中，CYP1B1在视网膜血管发育和新生血管形成中起重要作用。 视网膜病变(空气)。CYP1B1缺陷(CyP1B1-/-)小鼠表现出视网膜血管密度降低，并且在空气中无法使其视网膜新生血管。更重要的是。由CYP1B1-/-小鼠制备的视网膜内皮细胞迁移较少，不能在Matrigel中进行毛细血管形态发生。这些细胞还表达数量增加的凝血酶敏感蛋白-2(TSP2)。一种血管生成的内源性抑制物，其表达受细胞氧化应激的调节。我们的假设是，在Check中，CYP1B1在维持内皮细胞的氧化还原状态方面发挥着核心作用，因此在缺乏它的情况下，增加的氧化应激促进了NF-KB和TSP2的持续激活，并抑制了血管生成。我们现在已经证明，TSP2表达的变化介导了 CYP1B1缺陷对视网膜血管生成和培养的视网膜内皮细胞毛细血管形态发生的影响我们还发现，在OIR期间，氧化状态的增加介导了CYP1B1缺乏对视网膜新生血管的影响，并且在存在抗氧化剂的情况下可以被逆转。此外，在体外，细胞色素P1B1表达的变化足以影响TSP2的表达和视网膜EC毛细血管的形态发生。因此，这些变化是由细胞内的氧化应激以细胞色素P1B1依赖的方式调节的。在这里，我们将确定活性氧物种的来源，并描述氧化还原敏感转录因子NF-KB在TSP2增加中的潜在调节作用 表情。我们还将确定核因子-KB的表达是否受CYP1B1通过去除氧化产物的调节。了解CYP1B1及其代谢物如何调节视网膜血管动态平衡将有助于深入了解CYP1B1的作用机制，并有助于开发替代方法来调节视网膜血管生成。

The expression of specific cytochrome P450s (CYPs) in vascular smooth muscle cells and endothelial cells (EC). and the critical contribution of their products to vascular function suggest important roles for these genes in vascular homeostasis. Although lack of CYP1 B1 is shown to influence the function and development of the trabecular meshwork. Its physiological role in the development of retinal vasculature and angiogenesis has not been previously studied. Our preliminary data indicate that CYP1 B1 plays an essential role in retinal vascular development and neovascularization during oxygen-induced ischemic retinopathy (aiR). The CYP1 B1-deficient (CYP1 B1-/-) mice exhibit reduced retinal vascular density and fail to neovascularize their retina during aiR. Furthermore. retinal EC prepared from CYP1B1-/- mice are less migratory and fail to undergo capillary morphogenesis in Matrigel. These cells also express increased amounts of thrombospondin-2 (TSP2). an endogenous inhibitor of angiogenesis whose expression is modulated by cellular oxidative stress. Our hypothesis is that CYP1 B1 plays a central role in maintaining the redox state of the endothelium in check, such that in its absence increased oxidative stress promotes sustained activation of NF-KB and TSP2 expression, and inhibits angiogenesis. We have now shown that changes in TSP2 expression mediate the effects of CYP1 B1-deficiency on retinal vascularization in vivo and capillary morphogenesis of retinal EC in culture. We have also shown increased oxidative state mediates these effects of CYP1B1-deficiency on retinal neovascularization during OIR and can be reversed in the presence of an antioxidant. In addition changes in CYP1 B 1 expression are sufficient to affect TSP2 expression and retinal EC capillary morphogenesis in vitro. Therefore these changes are modulated by the intracellular oxidative stress in a CYP1 B1 dependent manner. Here we will determine the source of reactive oxygen species and will delineate the potential regulatory role of redox sensitive transcription factors NF-KB in increased TSP2 expression. We will also determine whether expression of NF-KB is modulated by CYP1 B1 through removal of oxygenation products. Understanding how CYP1 B1 and its metabolites regulate retinal vascular homeostasis will provide insight into CYP1 B1 mechanisms of action and aid in the development of alternative ways to modulate retinal angiogenesis.