Regulation of myogenesis and skeletal muscle function by bioactive lipid class switching

通过生物活性脂质类别转换调节肌生成和骨骼肌功能

• 批准号: RGPIN-2018-05979
• 负责人: Dumont, Nicolas
• 金额: $ 2.48万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=685347
• 关键词: Regulation; myogenesis; skeletal; muscle; function

Rationale: The formation of new muscle tissue, named myogenesis, is a tightly regulated process that plays a vital role in skeletal muscle development and growth. During that process, muscle stem cells (MuSCs) enter the cell cycle to become proliferating myoblasts, which eventually self-renew or differentiate and fuse to form new muscle fibers. ***How the cell fate decision of MuSCs is regulated during myogenesis is of great interest in the field. Our research project proposes that bioactive lipids class switching is a central process regulating the cell fate decision of MuSCs. Lipid mediator class switching is a process during which fatty acids (such as omega-3 or -6) are initially transformed into pro-inflammatory lipids; and thereafter into pro-resolving lipids. This process plays a key role in the regulation of inflammation; however, its impact on MuSCs has never been investigated. A better comprehension of the mechanisms regulating MuSC decision-making during myogenesis will open new possibilities to regulate their cell fate decision in vitro, which is a great challenge in the field.******Objective and hypothesis: The overall goal of this research project is to characterize the impact of lipid mediator class switching on MuSC and skeletal muscle function. We hypothesize that there is a switch during myogenesis that favours the biosynthesis of pro-resolving lipids, which promote late myogenic events (such as cell differentiation and fusion). This proposal is divided in 3 aims:******Aim 1: Define the bioactive lipid mediator class switching during myogenesis. Using biomolecular techniques (mass spec, RT-qPCR, western blot), we will assess the expression of bioactive lipids and their receptors by MuSCs at different stages of myogenesis.***Aim 2: Determine the mechanism of action and the impact of lipid mediator class switching on cell cycle regulation of myogenic cells. Using MuSC deficient in the enzymes responsible for bioactive lipid biosynthesis, we will determine the impact and the mechanism of action of lipid mediator class switching on the cell fate decision of MuSCs.***Aim 3: Determine the effect of bioactive lipids class switching on myotube and skeletal muscle function. Using in vitro and in vivo experiments we will assess the impact of bioactive lipid class switching on the function of newly-formed muscle fiber and skeletal muscles.******Relevance: We expect that this research project will uncover a completely novel mechanism regulating MuSC decision-making during myogenesis, which is of broad and current interest in the field. This research project will set the foundation stone of our research program aiming to develop novel methods to regulate stem cell fate. Particularly, the maintenance of cell stemness in vitro is of wide interest for bioengineers, investigators, and life science industries, which will lead to the development of strong partnerships with academia and industries in Canada.

原理：新的肌肉组织的形成，称为肌肉发生，是一个严格调控的过程，在骨骼肌的发育和生长中起着至关重要的作用。在这个过程中，肌肉干细胞(MuSCs)进入细胞周期，成为增殖的成肌细胞，最终自我更新或分化并融合形成新的肌肉纤维。*在肌肉发生过程中如何调控MuSCs的细胞命运决定一直是该领域的研究热点。我们的研究项目提出，生物活性脂类转换是调节MUSCs细胞命运决定的中心过程。脂质介体类转换是一个过程，在这个过程中，脂肪酸(如omega-3或-6)最初转化为促炎脂质，然后转化为促分解脂质。这一过程在炎症的调节中起着关键作用；然而，它对MuSCs的影响从未被研究过。更好地理解肌肉发生过程中调控MUSC决策的机制将为在体外调控MUSC的细胞命运决定开辟新的可能性，这是该领域的一个巨大挑战。目的和假设：本研究的总体目标是表征脂质介质类切换对MUSC和骨骼肌功能的影响。我们假设，在肌肉发生过程中有一个开关，有利于促进促进晚期肌肉形成事件(如细胞分化和融合)的促分解脂的生物合成。该提案分为三个目标：*目标1：定义肌肉发生过程中生物活性脂质介体类的转换。利用生物分子技术(质谱仪、RT-qPCR、Western印迹)，我们将研究肌源性细胞在不同阶段的生物活性脂类及其受体的表达。*目的2：确定脂类转换对肌源性细胞细胞周期调控的作用机制和影响。利用缺乏生物活性脂质生物合成的酶的MUSC，我们将确定脂类转换对MUSCs细胞命运决策的影响及其作用机制。*目的3：确定生物活性脂类转换对肌管和骨骼肌功能的影响。利用体外和体内实验，我们将评估生物活性脂类转换对新形成的肌肉纤维和骨骼肌功能的影响。*相关性：我们期待这项研究项目将揭示一种全新的机制，调节肌肉发生过程中的MUSC决策，这是该领域广泛和当前的兴趣。这项研究项目将为我们的研究计划奠定基础，旨在开发新的方法来调控干细胞的命运。特别是，在体外维持细胞干细胞能力引起了生物工程师、研究人员和生命科学行业的广泛兴趣，这将导致与加拿大学术界和行业发展牢固的合作伙伴关系。