Rexius-Hall Megan L, Madrigal Malinda D, Kilic Cem Y, Shen Keyue, McCain Megan L
Alfred E. Mann Department of Biomedical Engineering, USC Viterbi School of Engineering, University of Southern California, 1042 Downey Way, DRB 140, Los Angeles, CA 90089, USA.
Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, USA.
Lab Chip. 2025 Jan 14;25(2):212-224. doi: 10.1039/d4lc00603h.
Disrupted blood flow in conditions such as peripheral artery disease and critical limb ischemia leads to variations in oxygen supply within skeletal muscle tissue, creating regions of poorly perfused, hypoxic skeletal muscle surrounded by regions of adequately perfused, normoxic muscle tissue. These oxygen gradients may have significant implications for muscle injury or disease, as mediated by the exchange of paracrine factors between differentially oxygenated tissue. However, creating and maintaining heterogeneous oxygen landscapes within a controlled experimental setup to ensure continuous paracrine signaling is a technological challenge. Here, we engineer oxygen-controlled microphysiological systems to investigate paracrine interactions between differentially oxygenated engineered muscle tissue. We fabricated microphysiological systems with dual oxygen landscapes that also had engineered control over paracrine interactions between hypoxic and normoxic skeletal muscle tissues, which were differentiated from C2C12 myoblasts cultured on micromolded gelatin hydrogels. The microphysiological systems interfaced with a new 3D-printed oxygen control well plate insert, which we designed to distribute flow to multiple microphysiological systems and minimize evaporation for longer timepoints. With our system, we demonstrated that amphiregulin, a myokine associated with skeletal muscle injury, exhibits unique upregulation in both gene expression and secretion after 24 hours due to paracrine interactions between hypoxic and normoxic skeletal muscle tissue. Our platform can be extended to investigate other impacts of paracrine interactions between hypoxic and normoxic skeletal muscle and can more broadly be used to elucidate many forms of oxygen-dependent crosstalk in other organ systems.
在诸如外周动脉疾病和严重肢体缺血等情况下，血流中断会导致骨骼肌组织内氧气供应的变化，从而形成灌注不良、缺氧的骨骼肌区域，其周围是灌注充足、正常氧合的肌肉组织区域。这些氧梯度可能对肌肉损伤或疾病具有重要影响，这是由不同氧合组织之间旁分泌因子的交换介导的。然而，在可控的实验装置中创建并维持异质氧环境以确保持续的旁分泌信号传导是一项技术挑战。在此，我们设计了氧控微生理系统，以研究不同氧合的工程化肌肉组织之间的旁分泌相互作用。我们制造了具有双氧环境的微生理系统，该系统还对缺氧和正常氧合的骨骼肌组织之间的旁分泌相互作用进行了工程控制，这些组织是由在微模塑明胶水凝胶上培养的C2C12成肌细胞分化而来的。该微生理系统与一个新的3D打印氧控孔板插入件相连，我们将其设计用于将流体分配到多个微生理系统，并在较长时间点最大限度地减少蒸发。通过我们的系统，我们证明了双调蛋白，一种与骨骼肌损伤相关的肌动蛋白，由于缺氧和正常氧合的骨骼肌组织之间的旁分泌相互作用，在24小时后基因表达和分泌均表现出独特的上调。我们的平台可以扩展到研究缺氧和正常氧合的骨骼肌之间旁分泌相互作用的其他影响，并且更广泛地用于阐明其他器官系统中多种形式的氧依赖性串扰。
