CaMK: central regulators of the inflammatory response to surgical sepsis

CaMK：手术败血症炎症反应的中央调节因子

• 批准号: 8516525
• 负责人: MATTHEW Randall ROSENGART
• 金额: $ 30.09万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-03 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8516525
• 关键词: Biological; Biological Process; Ca(2+)-Calmodulin Dependent Protein Kinase; CaM kinase I activator; Calcium; Calcium/calmodulin-dependent protein kinase; Cause of Death; Cell Death; Cessation of life; Complex; Critical Illness; Data; Development; Exhibits; Family; Foundations; Functional disorder; Genetically Engineered Mouse; HMGB1 gene; Health; Inflammation; Inflammatory Response; Interleukin-10; Interleukin-6; Knockout Mice; Ligation; Link; MAP Kinase Gene; MAPK14 gene; MAPK8 gene; Maps; Mediating; Mediator of activation protein; Modeling; Mus; Operative Surgical Procedures; Optics; Organ; Pathway interactions; Patients; Production; Protein-Serine-Threonine Kinases; Puncture procedure; RNA Interference; Regulation; Renal function; Role; Ryanodine Receptor Calcium Release Channel; Sepsis; Signal Pathway; Signal Transduction; Spatial Distribution; Speed; Supplementation; Surgical Models; System; TLR4 gene; TNF gene; Techniques; Testing; United States; base; clinically relevant; design; improved; in vivo; insight; macrophage; mortality; novel; nucleocytoplasmic transport; response; septic

DESCRIPTION (provided by applicant): The complex biological processes of sepsis are poorly understood, which has hindered the development of sepsis-specific therapies, reflected by a mortality rate that has remained unchanged for 25 years. Impaired calcium (Ca2+) handling has been cited as the mediator of aberrant inflammation underlying the cell death and organ dysfunction of sepsis. Surprisingly, little is known of how this prevalent (88% of severely septic patients) pathophysiologic condition develops nor the signaling pathways and cellular responses regulated by these altered Ca2+ signals. Recently, we identified the calcium/calmodulin-dependent protein kinases (CaMK), a family of serine/threonine kinases responsive to intracellular Ca2+ concentration [Ca2+], mediate Ca2+-dependent signaling in the MF. We now recognize that CaMK, specifically CaMKI and IV, are operant in vivo and regulate key mediators of septic inflammation implicated in organ dysfunction and death. This proposal will focus upon the mechanisms by which CaMKI and IV mediate LPS induced Ca2+ signaling in MF. We propose that following LPS stimulation of the TLR4 pathway in MF, a ryanodine receptor (RyR)-gated cytosolic Ca2+ transient activates CaMKI and CaMKIV. CaMKI and CaMKIV, in turn, regulate the release of HMGB1, TNFa, and IL-10, key mediators of septic inflammation. CaMKI and CaMKIV assume distinct roles in mediating this inflammation, which we will define. In Aim 1 we will utilize high-speed, depth resolved optical mapping of Ca2+ transients and genetically engineered mice lacking key components of TLR4 and CaMK signaling pathways to characterize the mechanisms of LPS-induced Ca2+ signaling and CaMK activation in MF. Aim 2 will determine the mechanisms of CaMKI- and CaMKIV-dependent regulation of HMGB1 release from MF, as HMGB1 has been causally associated with septic mortality. In Aim 3 we show that these mechanisms are operant in an in vivo CLP model of surgical sepsis. We will show, using in vivo CaMK RNAi and mice deficient in the expression of CaMKIV, that CaMKI and CaMKIV regulate the inflammatory response during sepsis, and we will define their roles in organ dysfunction and death. The combined studies may provide key insights linking Ca2+ signaling in MF to the dysregulated Ca2+ handling underlying the inflammation and organ dysfunction of sepsis. PUBLIC HEALTH RELEVANCE: This project will determine TLR4-dependent calcium and calcium/calmodulin-dependent protein kinase (CaMK) signaling in macrophages and establish perturbations in these transduction systems as a biological mechanism underlying the inflammation and organ dysfunction of sepsis. An understanding of these mechanisms will increase our understanding of inflammation, prove useful in the design of novel forms of immunomodulatory therapy, and provide insight into the potential detriment of current practices of calcium supplementation in critical illness.

描述（由申请人提供）：人们对脓毒症的复杂生物学过程知之甚少，这阻碍了脓毒症特异性疗法的开发，25 年来死亡率保持不变就反映了这一点。钙 (Ca2+) 处理受损被认为是导致败血症细胞死亡和器官功能障碍的异常炎症的介质。令人惊讶的是，人们对这种普遍存在的（88% 严重脓毒症患者）病理生理状况如何发展以及这些改变的 Ca2+ 信号调节的信号通路和细胞反应知之甚少。最近，我们鉴定了钙/钙调蛋白依赖性蛋白激酶 (CaMK)，这是一个对细胞内 Ca2+ 浓度 [Ca2+] 敏感的丝氨酸/苏氨酸激酶家族，介导 MF 中的 Ca2+ 依赖性信号传导。我们现在认识到 CaMK，特别是 CaMKI 和 IV，在体内发挥作用，并调节与器官功能障碍和死亡有关的脓毒症炎症的关键介质。该提案将重点关注 CaMKI 和 IV 介导 MF 中 LPS 诱导的 Ca2+ 信号传导的机制。我们提出，在 MF 中 LPS 刺激 TLR4 通路后，兰尼碱受体 (RyR) 门控的胞质 Ca2+ 瞬时激活 CaMKI 和 CaMKIV。 CaMKI 和 CaMKIV 反过来调节 HMGB1、TNFa 和 IL-10（化脓性炎症的关键介质）的释放。 CaMKI 和 CaMKIV 在介导这种炎症方面发挥着不同的作用，我们将对其进行定义。在目标 1 中，我们将利用 Ca2+ 瞬变和缺乏 TLR4 和 CaMK 信号通路关键成分的基因工程小鼠的高速、深度分辨光学图谱来表征 MF 中 LPS 诱导的 Ca2+ 信号传导和 CaMK 激活的机制。目标 2 将确定 CaMKI 和 CaMKIV 依赖性调节 MF 释放 HMGB1 的机制，因为 HMGB1 与脓毒症死亡率存在因果关系。在目标 3 中，我们证明这些机制在手术脓毒症的体内 CLP 模型中是有效的。我们将使用体内 CaMK RNAi 和 CaMKIV 表达缺陷的小鼠证明，CaMKI 和 CaMKIV 调节脓毒症期间的炎症反应，并且我们将确定它们在器官功能障碍和死亡中的作用。综合研究可能提供关键见解，将 MF 中的 Ca2+ 信号传导与脓毒症炎症和器官功能障碍背后的 Ca2+ 处理失调联系起来。公共健康相关性：该项目将确定巨噬细胞中 TLR4 依赖性钙和钙/钙调蛋白依赖性蛋白激酶 (CaMK) 信号传导，并确定这些转导系统中的扰动作为脓毒症炎症和器官功能障碍的生物学机制。了解这些机制将增加我们对炎症的理解，有助于设计新型免疫调节疗法，并深入了解当前危重疾病补钙实践的潜在危害。