CYP4F3 in renal inflammation

CYP4F3在肾脏炎症中的作用

• 批准号: 8197931
• 负责人: PETER CHRISTMAS
• 金额: $ 36.74万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-02-08 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8197931
• 关键词: Address; Anti-Inflammatory Agents; Anti-inflammatory; Arachidonic Acids; Attenuated; Autacoids; Blood Circulation; Blood capillaries; CYP4F3A; Cells; Chemicals; Chemotaxis; Disease; Down-Regulation; Enzyme Inhibition; Enzyme Kinetics; Enzymes; Exposure to; GRK6 gene; Gene Expression; Genes; Genetic; Graft Rejection; Homologous Gene; Human; Immigration; In Vitro; Infiltration; Inflammation; Inflammation Mediators; Inflammatory; Injury; Ischemia; Kidney; Kidney Diseases; Kidney Failure; Kidney Transplantation; Knock-out; LTB4R gene; Lead; Leukocytes; Leukotriene B4; Leukotriene B4 Receptors; Life; Lymphocyte; Measures; Mediating; Modeling; Mus; Operating System; Pathologic; Peptide Hydrolases; Peripheral; Phase; Play; Property; Public Health; Regulation; Regulatory Pathway; Reperfusion Injury; Reporting; Research; Role; Signal Transduction; Site; Small Interfering RNA; System; T-Lymphocyte Subsets; Testing; Time; Tissues; Transcriptional Regulation; attenuation; capillary; cell injury; chemokine; enzyme activity; eosinophil; in vitro Assay; in vivo; inhibitor/antagonist; macrophage; mortality; mouse model; neutrophil; paracrine; prevent; receptor; renal ischemia; research study; response

DESCRIPTION (provided by applicant): Leukotriene B4 (LTB4) is a potent inflammatory mediator, derived from arachidonic acid, which plays a prominent role in ischemia-reperfusion injury and inflammation of the kidney. The enzyme CYP4F3 has specialized properties which enable it to inactivate LTB4: it has a uniquely low Km for LTB4 as a substrate, and it has a restricted localization to leukocytes which mediate LTB4-dependent responses. The hypothesis of this proposal is that CYP4F3 negatively regulates inflammation by attenuating the activities of LTB4. To test this hypothesis, three specific aims are proposed: (1) to investigate the regulation of LTB4-dependent responses by CYP4F3 in leukocytes in vitro; (2) to investigate the mechanism by which CYP4F3 regulates inflammation; and (3) to investigate the role of the mouse homologue of CYP4F3 (CYP4F18) in renal disease in vivo. In Specific Aim 1, CYP4F3 enzyme activity in leukocytes will be inhibited using a specific chemical inhibitor, a lentiviral- delivered siRNA approach, and a mouse genetic knockout, and the ability of LTB4 to stimulate cell chemoattraction and secretion will be measured using in vitro assays. The uniqueness of CYP4F3 function will be assessed by comparing other enzymes which metabolize LTB4 with higher Km values. In Specific Aim 2, receptor studies will be performed to determine if the product of LTB4 inactivation (20-OH LTB4) promotes LTB4 receptor (BLT1) down-regulation, thus providing a doubly efficient attenuation mechanism. The integration of CYP4F3 and BLT1 activity will be further investigated by determining the effects of CYP4F3:BLT1 expression ratio on LTB4 responsiveness. In Specific Aim 3, a mouse model of renal ischemia-reperfusion injury will be used to determine if targeted deletion of the CYP4F18 gene leads to increased inflammation and cell injury in vivo. These studies are relevant to public health because ischemic injury and inflammation are primary pathophysiological mechanisms leading to disorders of the kidney, such as renal failure and transplant rejection, which are associated with a high mortality rate. The significance of the research is that CYP4F3 provides a natural (non-toxic) anti-inflammatory target that might be selectively modulated in specific tissues such as the kidney. The long-term objectives are to correlate changes in CYP4F3 activity with inflammatory disease states in humans, and to identify and manipulate the regulatory pathways that control CYP4F3 gene expression and activity.

描述（由申请人提供）：白细胞B4（LTB4）是一种有效的炎症介质，源自蛛网膜酸，它在肾脏灌注损伤和肾脏的炎症中起着重要作用。酶CYP4F3具有专门的特性，使其能够使LTB4失活：对于LTB4作为底物具有独特的低km km，并且对介导LTB4依赖反应的白细胞具有限制定位。该提议的假设是CYP4F3通过减轻LTB4的活性来负调节炎症。为了检验这一假设，提出了三个具体目标：（1）研究在体外白细胞中CYP4F3对LTB4依赖性响应的调节； （2）研究CYP4F3调节炎症的机制； （3）研究CYP4F3（CYP4F18）小鼠同源物在体内肾脏疾病中的作用。在特定的目标1中，使用特定的化学抑制剂，慢病毒 - 输送的siRNA方法和小鼠遗传敲除的CYP4F3酶活性将被抑制白细胞中的CYP4F3酶活性，以及​​LTB4刺激细胞化学提取和分泌的能力。 CYP4F3函数的唯一性将通过比较其他将LTB4代谢的酶进行评估。在特定的目标2中，将进行受体研究，以确定LTB4失活的乘积（20-OH LTB4）是否促进了LTB4受体（BLT1）下调，从而提供了双重有效的衰减机制。通过确定CYP4F3：BLT1表达比对LTB4响应性的影响，将进一步研究CYP4F3和BLT1活性的整合。在特定的目标3中，将使用肾脏缺血再灌注损伤的小鼠模型来确定CYP4F18基因的靶向缺失是否导致体内炎症和细胞损伤增加。这些研究与公共卫生有关，因为缺血性损伤和炎症是导致肾脏疾病的主要病理生理机制，例如肾衰竭和移植排斥，这与高死亡率有关。这项研究的意义在于，CYP4F3提供了一种天然（无毒的）抗炎靶标的，可以在特定组织（例如肾脏）中选择性地调节。长期目标是将CYP4F3活性的变化与人类的炎性疾病状态相关联，并确定和操纵控制CYP4F3基因表达和活性的调节途径。

项目成果

Altered leukotriene B4 metabolism in CYP4F18-deficient mice does not impact inflammation following renal ischemia.

• DOI: 10.1016/j.bbalip.2014.03.002
• 发表时间: 2014-06
• 期刊: Biochimica et biophysica acta
• 作者: Winslow V;Vaivoda R;Vasilyev A;Dombkowski D;Douaidy K;Stark C;Drake J;Guilliams E;Choudhary D;Preffer F;Stoilov I;Christmas P
• 通讯作者: Christmas P

CYP4F18-Deficient Neutrophils Exhibit Increased Chemotaxis to Complement Component C5a.

• DOI: 10.1155/2015/250456
• 发表时间: 2015
• 期刊: Journal of immunology research
• 影响因子: 4.1
• 作者: Vaivoda R;Vaine C;Boerstler C;Galloway K;Christmas P
• 通讯作者: Christmas P