Role of C3a Receptors and C5a Receptors on Mesenchymal Stem Cells

C3a 受体和 C5a 受体对间充质干细胞的作用

• 批准号: 7897537
• 负责人: SOPHIA K KHALDOYANIDI
• 金额: $ 27万
• 依托单位: TORREY PINES INST FOR MOLECULAR STUDIES
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-05 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7897537
• 关键词: Anaphylatoxins; Angiogenic Factor; Animal Model; Apoptosis; Area; Arrestins; Basic Amino Acids; Biological; C5a anaphylatoxin receptor; Cardiac; Cardiac Myocytes; Cell Nucleus; Cell Proliferation; Cell physiology; Cells; Chemotactic Factors; Complement 3a; Complement 5a; Congestive Heart Failure; Data; Deposition; Dorsal; Endothelial Cells; Engraftment; Fibroblast Growth Factor 2; Future; G-Protein-Coupled Receptors; Granulation Tissue; Growth Factor; Healed; Health; Heart; Homing; Human; Implant; In Vitro; Inflammation; Injury; Lead; Measures; Mediating; Mesenchymal Stem Cells; Modeling; Mus; Myocardial; Myocardial Infarction; Natural regeneration; Nuclear; Nuclear Extract; Nuclear Translocation; Operative Surgical Procedures; Outcome; PECAM1 gene; Pathway interactions; Phosphorylation; Physiological; Play; Porifera; Production; Receptor Activation; Resolution; Retrieval; Role; Signal Pathway; Signal Transduction; Signaling Molecule; Site; Source; Stem cell transplant; Stem cells; Time; Tissues; Transcriptional Activation; Up-Regulation; Vascular Endothelial Growth Factors; Wild Type Mouse; angiogenesis; base; beta-arrestin; cell motility; cell type; cytokine; design; healing; improved; in vivo; inhibitor/antagonist; injured; interest; intravital microscopy; meetings; migration; monolayer; mouse model; mutant; novel; public health relevance; receptor; receptor binding; receptor expression; repaired; response; stem cell differentiation; translational study

DESCRIPTION (provided by applicant): Myocardial infarction and subsequent congestive heart failure are among the most challenging and prevalent health problems. Stem cell transplantation has the potential to allow cardiac repair, and mesenchymal stem cells (MSC) are among the promising cell types for cardiac regeneration, although many challenges remain, before stem cells will lead to curative therapy, and it is currently more realistic to aim for stem cell-mediated improved revascularization than for cardiomyocyte replacement. One possible approach is to instruct MSC in vitro in ways which will increase their propensity for homing and engraftment to the diseased heart. We hypothesize that the anaphylatoxins C3a and C5a are one such means. Our preliminary studies surprisingly showed that the C3a receptor (C3aR) is translocated to the nucleus in MSC, but not in other cell types. Interestingly, nuclear translocation of other G-protein-coupled receptors has been associated with prolonged activation of signaling pathways and transcriptional activation, which may result in cardioprotection, and indeed MSCs stimulated with C3a up-regulate several trophic and angiogenic factors. Aim 1: To determine the effect of C3a and C5a on MSC functions which are relevant to their cardiac repair potential: Hypothesis: C3a and C5a have effects on MSCs that will improve their potential as transplantable cells for cardiac repair. This is based on the observation that C3a and C5a both cause long-lasting activation of signaling pathways (ERK and Akt) that are associated with MSC expansion, production of cardioprotective growth factors and differentiation toward cardiomyocytes. Important facets of MSC function (cell migration, production of trophic factors, proliferation and differentiation) will be determined in MSCs stimulated with C3a or C5a. These functions will be determined both in vitro and in vivo. Aim 2: To characterize the nuclear translocation of the C3aR and associated signaling molecules in C3a-stimulated MSCs and to determine the effect of the nuclear translocation and the prolonged ERK1/2 and Akt activation on MSC function. Aim 2.1: Hypothesis: The C3aR in MSCs translocates to the nucleus, which is associated with prolonged activation of signaling pathways and transcriptional activation. Nuclear translocation of the C3aR, phospho-ERK1/2, phospho-Akt and beta-arrestin will be determined in nuclear extracts of C3a-stimulated human MSCs. C5a will be used for comparison. Means of inhibiting nuclear translocation of the C3aR will be used to determine the role of the nuclear translocation on cell signaling (Aim 2.1) and cell function (Aim 2.2). Aim 2.2: To determine the effect of the nuclear translocation and the prolonged C3a and C5a-mediated ERK1/2 and Akt activation on MSC function. Hypothesis: The prolonged activation of ERK1/2 and/or Akt pathways - and in the case of the C3aR, the nuclear translocation of this receptor - are responsible for the functional effects of C3a and C5a. The effect of inhibition of ERK1/2 and Akt and of nuclear translocation of the C3aR on specific C3a or C5a mediated functions will be assessed in order to determine which signaling pathway mediates which effect. PUBLIC HEALTH RELEVANCE: Myocardial infarction and subsequent congestive heart failure remain among the most challenging and prevalent health problems. Stem cell transplantation has the potential to allow cardiac repair, and mesenchymal stem cells (MSCs) are among the promising cell types for cardiac regeneration. One possible approach is to instruct MSCs in vitro in ways which will increase their potential for engraftment and homing to the diseased heart. We hypothesize that the chemotactic factors C3a and C5a are one such means. In this proposal the functional role of C3a and C5a on MSC will be investigated.

描述（由申请人提供）：心肌梗死和随后的充血性心力衰竭是最具挑战性和最普遍的健康问题之一。干细胞移植具有修复心脏的潜力，而间充质干细胞（MSC）是心脏再生的有希望的细胞类型之一，尽管在干细胞将导致治愈性治疗之前仍存在许多挑战，目前以干细胞介导的改善血运重建为目标比心肌细胞替代更现实。一种可能的方法是在体外指导MSC，以增加其归巢和植入病变心脏的倾向。我们假设过敏毒素C3a和C5a就是其中一种。我们的初步研究令人惊讶地表明，C3a受体（C3aR）在MSC中易位到细胞核，但在其他细胞类型中没有。有趣的是，其他g蛋白偶联受体的核易位与信号通路和转录激活的延长激活有关，这可能导致心脏保护，并且C3a刺激的间充质干细胞确实上调了几种营养和血管生成因子。目的1：确定C3a和C5a对与其心脏修复潜能相关的间充质干细胞功能的影响：假设：C3a和C5a对间充质干细胞有影响，可提高其作为心脏修复移植细胞的潜力。这是基于观察到C3a和C5a都引起信号通路（ERK和Akt）的持久激活，这些信号通路与MSC扩张、心脏保护生长因子的产生和向心肌细胞的分化有关。间充质干细胞功能的重要方面（细胞迁移、营养因子的产生、增殖和分化）将在C3a或C5a刺激的间充质干细胞中决定。这些功能将在体内和体外被确定。目的2：表征C3aR和相关信号分子在c3a刺激的MSC中的核易位，并确定核易位和延长的ERK1/2和Akt激活对MSC功能的影响。Aim 2.1：假设：MSCs中的C3aR易位到细胞核，这与信号通路的延长激活和转录激活有关。C3aR、phospho-ERK1/2、phospho-Akt和β -arrestin的核易位将在c3a刺激的人MSCs的核提取物中测定。C5a将用于比较。抑制C3aR核易位的方法将用于确定核易位对细胞信号传导（Aim 2.1）和细胞功能（Aim 2.2）的作用。目的2.2：确定核易位及C3a和c5a介导的ERK1/2和Akt的延长活化对MSC功能的影响。假设：ERK1/2和/或Akt通路的长时间激活——在C3aR的情况下，这种受体的核易位——是C3a和C5a功能作用的原因。我们将评估ERK1/2和Akt的抑制以及C3aR的核易位对特定C3a或C5a介导的功能的影响，以确定哪种信号通路介导哪种作用。