Engineered Heterochronic Parabiosis on 3D Microphysiological Systems

项目总结 异慢性异种共生，即幼年和老年动物通过外科手术附着在共享循环上，提供 存在所谓的“抗老年病”因素的证据，但循环因素的调节机制是存在的 肌肉干细胞的返老还童特性及其微环境尚未被阐明。由于 体内异种共生的复杂性和血液传播因素的动态性质，可靠地识别这些 幽默因素仍然是一个主要障碍。为了克服这一挑战，张博士和他的团队将利用 先进的微工程方法来构建可以控制机械装置的三维微流控异生电路 以及生理上相关的3D微环境中的生化线索。在这项提案中，他的团队将进一步 通过整合特定细胞类型的蛋白质标记系统改进和升级体外异种生殖平台 (MetRSL2774G转基因)精确识别肌肉分泌体，也称为肌动蛋白，负责 肌肉干细胞的返老还童效应。此外，还将采用目标遗传学方法来 描述氧化应激诱导的对肌肉干细胞功能产生负面影响的促老年肌因子。 最后，该团队还将在芯片上设计一个运动诱导的肌细胞因子报告系统 使用与蛋白质标记构建物MetRSL274G共表达的光遗传致动器(通道视紫红质2)。 利用这位记者，拟议中的研究将确定具有抗老年特性的新型收缩诱导肌动蛋白。 以及通过血脑屏障(BBB)在肌肉-大脑串扰中发挥作用的肌肉激动素。这个 该项目的成功成果将对老年学产生深远而广泛的影响。这是一种微创 3D微生理系统可用于测试衰老或建模特征的各种研究 在体外研究与年龄相关的疾病。更重要的是，经过验证，此中使用的实验方法 建议可以翻译成模仿人类异种共生，这将具有重大的临床意义。

PROJECT SUMMARY Heterochronic parabiosis, in which young and aged animals are surgically attached to share circulation, provided evidence of putative ‘anti-geronic’ factors exist but the mechanisms by which circulating factors mediate rejuvenating properties on muscle stem cells and their microenvironment have yet to be elucidated. Due to the complexity of in vivo parabiosis and the dynamic nature of blood-borne factors, reliable identification of these humoral factors remains a major hurdle. To overcome this challenge, Dr. Jang and his team will leverage advanced microengineering approaches to build a 3D microfluidic parabiosis circuit that can control mechanical and biochemical cues in the physiologically relevant 3D microenvironment. In this proposal, his team will further refine and upgrade the in vitro parabiosis platform by integrating a cell-type-specific protein labeling system (MetRSL2774G transgene) to precisely identify muscle secretome, also known as myokines, responsible for rejuvenation effects on muscle stem cells. In addition, the targeted genetics approach will be employed to delineate oxidative stress-induced pro-geronic myokines that negatively impact muscle stem cell function. Finally, the team will also engineer an exercise-induced myokine reporter system within parabiosis-on-a-chip using an optogenetic actuator (Channelrhodopsin 2) co-expressed with protein labeling construct, MetRSL274G. Using this reporter, proposed studies will identify novel contraction-induced myokines with anti-geronic properties and myokines that pass the blood-brain-barrier (BBB) to exert their action on muscle-brain crosstalk. The successful outcomes of this project will have far and broad implications in geroscience. This minimally invasive 3D microphysiological system can be exploited in a variety of studies testing the hallmarks of aging or modeling of age-related diseases in vitro. More importantly, upon validation, the experimental approach used in this proposal can be translated to mimic human parabiosis, which will have significant clinical implications.