Roles of matricryptins (bioactive extracellular matrix fragments) in adipose tissue

基质隐蛋白（生物活性细胞外基质片段）在脂肪组织中的作用

• 批准号: RGPIN-2020-06363
• 负责人: Fradette, Julie
• 金额: $ 2.62万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=718301
• 关键词: Roles; matricryptins; bioactive; extracellular; matrix

Studying the instructive cues provided by the extracellular matrix (ECM) is crucial, and represents an emerging field for adipose tissue. Matricryptins are bioactive fragments generated by the proteolytic remodeling of the ECM. Importantly, these fragments exert intrinsic biological activities that can differ from those of their parent biomolecules. Matricryptins have been shown to regulate cell behavior, in particular for endothelial cells. We hypothesize that selected recombinant matricryptins can stimulate angiogenesis in adipose tissue while preserving the key metabolic functions of this tissue. We will use a biomimetic model of adipose tissue engineered in vitro featuring a microvasculature of endothelial cell-derived capillary networks. Our method is based on the capacity of adipose-derived stromal/stem cells (ASCs) to produce and assemble an abundant endogenous ECM while differentiating into adipocytes. Our specific aims are to: Ia. Determine the impact of selected matricryptin supplementation on endothelial cells and the developing microvasculature in engineered adipose tissues. Ib. Assess if these matricryptins affect adipocyte functions and adipogenesis. II. Determine the endogenous profiles of expression and release of matricryptins in adipose tissues. Aim Ia. Matricryptin candidates have been selected for their reported proangiogenic properties in specific contexts while their roles in adipose tissue are unknown. They will be supplemented into the culture media during adipose tissue formation in vitro and dose-response studies will be carried out. Detailed characterization of the capillary networks formed in matricryptin-enriched or control cultures will be performed by live monitoring as well as confocal microscopy. Aim Ib. The impact on lipolysis will be assessed by quantifying glycerol release by adipocytes upon isoproterenol stimulation. Adipokines with angiomodulatory actions will be quantified. The extent of differentiation of ASCs into adipocytes in presence of matricryptins will also be performed. Aim II. We will determine the endogenous profiles of expression and release of matricryptins in adipose tissue in absence of exogenously added matricryptins. We will identify and quantify the major matricryptins present in human adipose tissue using quantitative mass spectrometry on samples of engineered and native adipose tissues. Impact: The study of matricryptins in adipose tissues has been mostly focused so far on a single matricryptin, endotrophin. Our findings will reveal the capacity of other matricryptins to act as regulators of angiogenesis and/or adipogenesis in adipose tissue. This work will lead to a better understanding of the molecular mechanisms through which ECM components and their bioactive fragments can modulate the microenvironment and impact cell behavior during adipose tissue development and remodeling. Producing a map of matricryptin expression in adipose tissue will contribute novel basic knowledge.

研究细胞外基质（ECM）提供的指导性线索是至关重要的，代表了脂肪组织的新兴领域。基质隐蛋白是ECM蛋白水解重构产生的生物活性片段。重要的是，这些片段发挥内在的生物活性，可以不同于它们的母体生物分子。已显示基质密蛋白调节细胞行为，特别是对于内皮细胞。我们假设，选择的重组matricryptins可以刺激血管生成脂肪组织，同时保留该组织的关键代谢功能。 我们将使用一个仿生模型的脂肪组织工程在体外具有微血管内皮细胞衍生的毛细血管网络。我们的方法是基于脂肪来源的基质/干细胞（ASC）的能力，以产生和组装丰富的内源性ECM，同时分化成脂肪细胞。我们的目标是：确定选择的matricryptin补充对内皮细胞和工程化脂肪组织中微血管发育的影响。IB.评估这些matricryptins是否影响脂肪细胞功能和脂肪生成。二.确定脂肪组织中基质隐蛋白的内源性表达和释放谱。 Aim Ia.基质密码蛋白候选物已被选择为它们在特定情况下的促血管生成特性，而它们在脂肪组织中的作用是未知的。将在体外脂肪组织形成期间将其补充到培养基中，并进行剂量反应研究。将通过实时监测以及共聚焦显微镜对在富含matricryptin或对照培养物中形成的毛细血管网络进行详细表征。阿姆湾将通过定量异丙肾上腺素刺激后脂肪细胞的甘油释放来评估对脂解的影响。将量化具有血管调节作用的脂肪因子。还将进行在存在基质密蛋白的情况下ASC分化成脂肪细胞的程度。 Aim II.我们将确定内源性的表达和释放matricryptins在脂肪组织中的情况下，外源性添加matricryptins。我们将使用定量质谱法对工程化和天然脂肪组织的样品鉴定和定量存在于人类脂肪组织中的主要matricryptins。 影响：迄今为止，脂肪组织中的matricryptin的研究主要集中在单一的matricryptin，endotrophin上。我们的研究结果将揭示其他matricryptins作为调节血管生成和/或脂肪组织中的脂肪生成的能力。这项工作将导致更好地了解ECM成分及其生物活性片段在脂肪组织发育和重塑过程中调节微环境和影响细胞行为的分子机制。绘制脂肪组织中matricryptin表达的图谱将有助于新的基础知识。