CYPs/2D18 Limit Inflammation Cascade Following Brain Injury

描述(由申请人提供)：这项拨款申请提出了一种综合的多水平方法，以确定细胞色素P450 4F(CYP 4F)亚家族和CYP 2D18在使用受控皮质影响模型系统调控创伤性脑损伤(TBI)后炎症级联反应中的作用。在人类中，由于各种来源的脑损伤(如交通事故、暴力)导致的闭合性头部损伤构成了一个严重的、往往是棘手的临床问题，经常导致死亡或停止人工生命支持成为一个问题。脑外伤通过白三烯B和前列腺素触发炎症级联反应，导致液体、离子和细胞流入脑组织-随后的脑肿胀通常导致昏迷。我们对这个问题的解决首先是因为证明了CyP4F亚家族酶可以将炎症的白三烯和前列腺素介质代谢成非活性产物，从而可能起到减缓炎症级联的作用。其次，初步数据显示，在所研究的四种大鼠CYP 4F形式中，有三种在创伤后24小时海马区表达减少，在皮质撞击后三天至三周(即炎症阶段的恢复或逆转)表达增加。我们将通过确定CYP 4F形式和CYP 2D18在不同脑区和远端组织(即肝脏、肾脏等)中表达的变化来寻求这些初步数据。作为撞击后时间的函数。我们将表达、纯化和表征CYP 4F1和CYP 4F6对白三烯和前列腺素的催化活性，这两种形式是我们尚未表征的。我们将把脑损伤后细胞色素P4F和2D18表达的变化与炎症细胞标志物和体液信号分子(如IL-6、IL-1β、TNFpha)水平的变化联系起来，以检验所提出的细胞色素P4F调节炎症反应的假说。我们还将确定联合研究员P.Dash博士建立的脑外伤小鼠模型中细胞色素P4F和2D18的表达变化，以及炎症和信号分子标志物的变化，以确定脑损伤后正常和CTP4F14缺失表型小鼠的特定细胞色素P4F的作用。我们认为，这些方法将更好地定义脑外伤后炎性级联反应的调节。

DESCRIPTION (provided by applicant): This grant request proposes an integrated multilevel approach to define the role of the cytochrome P450 4F (CYP 4F) subfamily and CYP 2D18 in modulation of the inflammatory cascade following traumatic brain injury (TBI) using a controlled cortical impact model system. In humans, closed head injury resulting from various sources of trauma to the brain (e.g., traffic accidents, violence) constitutes a serious, often intractable clinical problem frequently leading to death or the situation where discontinuation of artificial life support becomes a question. TBI triggers the inflammatory cascade prompted through leukotriene B, and prostaglandins causing the influx of fluids, ions and cells into brain tissue - the subsequent brain swelling often leading to coma. Our approach to this problem is prompted first by the demonstration that the CYP 4F subfamily enzymes can metabolize the leukotriene and prostaglandin mediators of inflammation to inactive products with the possible effect of moderating the inflammatory cascade. Second, it is prompted by preliminary data which show that three out of four of the rat CYP 4F forms studied show a decrease in expression in the hippocampus at 24 hours after trauma and an increase in expression at three days through three weeks after cortical impact (i.e., the recovery or reversal of inflammation phase). We will pursue these preliminary data by defining the changes in expression of CYP 4F forms and CYP 2D18 in various brain regions and distal tissues (i.e., liver, kidney, etc.) as a function of time after impact. We will express, purify and characterize the catalytic activities toward leukotriene and prostaglandin of CYP 4F1 and CYP 4F6 the two remaining forms we have not characterized. We will correlate changes in CYP4F and 2D18 expression following TBI with cellular markers of inflammation and changes in levels of humoral signaling molecules (e.g. IL-6, IL-lbeta, TNFalpha) to test the hypothesis that CYP4Fs modulate inflammatory response as proposed. We will also define changes in the expression of CYP4F and 2D18 and changes in markers of inflammation and signaling molecules in the mouse model of TBI developed by Dr. P. Dash the co-investigator in order for normal and CTP4F14 null phenotype mice after TBI to define the role of a specific CYP4Fs. We feel these approaches will allow a better definition of the modulation of the inflammatory cascade after TBI.