CYPs/2D18 Limit Inflammation Cascade Following Brain Injury

描述（由申请人提供）：该资助申请提出了一种综合的多层次方法，以定义细胞色素P450 4F （CYP 4F）亚家族和CYP 2D18在创伤性脑损伤（TBI）后炎症级联调节中的作用，使用受控皮质冲击模型系统。在人类中，各种脑外伤（如交通事故、暴力）造成的闭合性头部损伤是一个严重的、往往难以解决的临床问题，往往导致死亡或中断人工生命支持成为一个问题。创伤性脑损伤引发了由白三烯B和前列腺素引发的炎症级联反应，导致体液、离子和细胞涌入脑组织——随后的脑肿胀往往导致昏迷。我们对这一问题的研究首先是由于CYP 4F亚家族酶可以将炎症介质白三烯和前列腺素代谢为无活性产物，可能具有调节炎症级联反应的作用。其次，初步数据表明，所研究的四种大鼠CYP 4F形式中有三种在创伤后24小时在海马中表达减少，在皮质冲击后3天至3周（即炎症期的恢复或逆转）表达增加。我们将通过定义撞击后不同脑区和远端组织（即肝脏、肾脏等）中CYP 4F形式和CYP 2D18表达随时间的变化来追求这些初步数据。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，这两种形式我们还没有表征。我们将把创伤性脑损伤后CYP4F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 - β、TNFalpha）水平的变化联系起来，以检验CYP4F调节炎症反应的假设。我们还将定义由P. Dash博士开发的TBI小鼠模型中CYP4F和2D18表达的变化以及炎症标记物和信号分子的变化，以便在TBI后正常和CTP4F14零表型小鼠中定义特定CYP4Fs的作用。我们认为这些方法将允许更好地定义脑外伤后炎症级联的调节。

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.