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: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=741167
• 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）提供的指导性提示至关重要，代表了脂肪组织的新兴领域。基质蛋白是由ECM的蛋白水解重塑产生的生物活性片段。重要的是，这些碎片发挥了内在的生物学活性，可能与母亲生物分子的生物分子不同。已显示基质蛋白可以调节细胞行为，特别是对于内皮细胞。我们假设选定的重组基质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。 我们将使用由内皮细胞衍生的毛细血管网络的微脉管系统进行体外设计的脂肪组织的仿生模型。我们的方法基于脂肪衍生的基质/干细胞（ASC）产生和组装丰富的内源性ECM的能力，同时区分脂肪细胞。我们的具体目的是：ia。确定所选基质蛋白补充对工程脂肪组织中内皮细胞和发育中的微脉管系统的影响。 IB。评估这些基质蛋白是否影响脂肪细胞功能和脂肪形成。 ii。确定脂肪组织中基质蛋白表达和释放的内源性谱。 瞄准。已经选择了母晶候选物，以在特定情况下报告其促血管生成特性，而其在脂肪组织中的作用却未知。在体外脂肪组织形成期间，它们将被补充到培养基中，并将进行剂量反应研究。在富含基质的毛细血管网络或对照培养物中形成的毛细血管网络的详细表征将通过实时监测以及共聚焦显微镜进行。目标IB。对脂解的影响将通过对异丙肾上腺素刺激的脂肪细胞释放来评估。具有血管调节作用的脂肪因子将被量化。还将在存在基质蛋白的情况下将ASC分化为脂肪细胞的程度。目标II。我们将在没有外源添加的基质蛋白的情况下确定脂肪组织中基质蛋白表达和释放的内源性谱。我们将使用在工程和天然脂肪组织的样品上使用定量的质谱法确定并量化人脂肪组织中存在的主要基质蛋白。影响：迄今为止，对脂肪组织中基质蛋白的研究主要集中在单一基质蛋白内托罗蛋白上。我们的发现将揭示其他基质蛋白在脂肪组织中充当血管生成和/或脂肪形成的调节剂的能力。这项工作将使人们更好地理解ECM成分及其生物活性片段可以调节微环境和在脂肪组织发育和重塑过程中影响细胞行为的分子机制。在脂肪组织中产生基质晶体表达的图将有助于新的基础知识。