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: 7906839
• 负责人: MATTHEW Randall ROSENGART
• 金额: $ 31.5万
• 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/7906839
• 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; Figs - dietary; Foundations; Functional disorder; Genetically Engineered Mouse; HMGB1 gene; 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; Ryanodine Receptors; Sepsis; Signal Pathway; Signal Transduction; Spatial Distribution; Speed; Supplementation; Surgical Models; System; TLR4 gene; Techniques; Testing; United States; base; clinically relevant; design; improved; in vivo; insight; macrophage; mortality; novel; nucleocytoplasmic transport; public health relevance; 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(申请人提供)：败血症的复杂生物学过程知之甚少，这阻碍了针对脓毒症的治疗方法的发展，这反映在25年来保持不变的死亡率上。钙(Ca~(2+))处理受损被认为是脓毒症细胞死亡和器官功能障碍的基础上的异常炎症的介质。令人惊讶的是，对于这种流行的(88%的严重败血症患者)病理生理状况是如何发展的，以及这些改变的钙信号调节的信号通路和细胞反应，人们知之甚少。最近，我们发现了钙/钙调蛋白依赖的蛋白激酶(CaMK)，这是一类对细胞内钙离子浓度[Ca~(2+)]有反应的丝氨酸/苏氨酸激酶家族，在MF中介导钙离子依赖的信号转导。我们现在认识到，CaMK，特别是CaMKI和IV，在体内是可操作的，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。这项建议将集中在CaMKI和IV介导内毒素诱导的MF钙信号转导的机制。我们认为，在内毒素刺激MF的TLR4通路后，兰尼定受体(RyR)门控的胞浆钙瞬变激活CaMKI和CaMKIV。CaMKI和CaMKIV反过来调节HMGB1、TNFa和IL-10的释放，这些都是败血症炎症的关键介质。CaMKI和CaMKIV在调节炎症中扮演着不同的角色，我们将对其进行定义。在目标1中，我们将利用高速、深度分辨的钙瞬变光学图谱和缺乏TLR4和CaMK信号通路关键成分的基因工程小鼠来表征内毒素诱导的钙信号和CaMK在MF中激活的机制。目的2将确定依赖CaMKI和CaMKIV调节MF释放HMGB1的机制，因为HMGB1与脓毒症死亡率有因果关系。在目标3中，我们证明了这些机制在外科脓毒症的活体CLP模型中是有效的。我们将利用体内CaMK RNAi和CaMKIV表达缺陷的小鼠，证明CaMKI和CaMKIV调节脓毒症时的炎症反应，并确定它们在器官功能障碍和死亡中的作用。联合研究可能提供关键的见解，将MF中的钙信号与脓毒症炎症和器官功能障碍潜在的失调的钙处理联系起来。公共卫生相关性：该项目将确定巨噬细胞中依赖TLR4的钙和钙/钙调素依赖的蛋白激酶(CaMK)信号，并在这些转导系统中建立扰动，作为脓毒症炎症和器官功能障碍的生物学机制。对这些机制的了解将增加我们对炎症的理解，证明对设计新形式的免疫调节治疗是有用的，并提供对当前危重疾病补钙做法的潜在有害的洞察。