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）提供的指导性线索至关重要，并且代表了脂肪组织的一个新兴领域。基质隐蛋白是 ECM 蛋白水解重塑产生的生物活性片段。重要的是，这些片段发挥与其母体生物分子不同的内在生物活性。基质隐蛋白已被证明可以调节细胞行为，特别是内皮细胞。我们假设选定的重组基质隐蛋白可以刺激脂肪组织中的血管生成，同时保留该组织的关键代谢功能。 我们将使用体外工程脂肪组织的仿生模型，其特征在于内皮细胞衍生的毛细血管网络的微血管系统。我们的方法基于脂肪源性基质/干细胞（ASC）在分化为脂肪细胞时产生和组装丰富的内源性 ECM 的能力。我们的具体目标是： Ia。确定选定的基质隐蛋白补充剂对工程脂肪组织中内皮细胞和发育中的微血管的影响。伊布。评估这些基质隐蛋白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蛋白表达和释放的内源性概况。 目标 Ia。 Matricryptin 候选物因其在特定情况下的促血管生成特性而被选择，但它们在脂肪组织中的作用尚不清楚。它们将在体外脂肪组织形成过程中补充到培养基中，并进行剂量反应研究。将通过实时监测和共聚焦显微镜对富含基质蛋白或对照培养物中形成的毛细血管网络进行详细表征。目标 Ib。通过量化脂肪细胞在异丙肾上腺素刺激后释放的甘油来评估对脂肪分解的影响。具有血管调节作用的脂肪因子将被量化。还将进行在基质隐蛋白存在下 ASC 分化为脂肪细胞的程度。 目标二。我们将确定在没有外源添加基质蛋白的情况下脂肪组织中基质蛋白的内源表达和释放概况。我们将使用定量质谱法对工程脂肪组织和天然脂肪组织样本进行鉴定和定量人类脂肪组织中存在的主要基质隐蛋白。 影响：迄今为止，脂肪组织中基质隐蛋白的研究主要集中在单一基质隐蛋白——内养蛋白上。我们的研究结果将揭示其他基质隐蛋白作为脂肪组织中血管生成和/或脂肪生成调节剂的能力。这项工作将有助于更好地理解 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并影响细胞行为的分子机制。绘制脂肪组织中基质蛋白表达图谱将有助于提供新的基础知识。