Musculoskeletal Science & Sports Medicine Research Centre, Department of Life Sciences, Manchester Metropolitan University, Manchester, UK.
Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK.
Physiol Rep. 2021 Apr;9(8):e14791. doi: 10.14814/phy2.14791.
Neuromuscular junction (NMJ) research is vital to advance the understanding of neuromuscular patho-physiology and development of novel therapies for diseases associated with NM dysfunction. In vivo, the micro-environment surrounding the NMJ has a significant impact on NMJ formation and maintenance via neurotrophic and differentiation factors that are secreted as a result of cross-talk between muscle fibers and motor neurons. Recently we showed the formation of functional NMJs in vitro in a co-culture of immortalized human myoblasts and motor neurons from rat-embryo spinal-cord explants, using a culture medium free from serum and neurotrophic or growth factors. The aim of this study was to assess how functional NMJs were established in this co-culture devoid of exogenous neural growth factors. To investigate this, an ELISA-based microarray was used to compare the composition of soluble endogenously secreted growth factors in this co-culture with an a-neural muscle culture. The levels of seven neurotrophic factors brain-derived neurotrophic factor (BDNF), glial-cell-line-derived neurotrophic factor (GDNF), insulin-like growth factor-binding protein-3 (IGFBP-3), insulin-like growth factor-1 (IGF-1), neurotrophin-3 (NT-3), neurotrophin-4 (NT-4), and vascular endothelial growth factor (VEGF) were higher (p < 0.05) in the supernatant of NMJ culture compared to those in the supernatant of the a-neural muscle culture. This indicates that the cross-talk between muscle and motor neurons promotes the secretion of soluble growth factors contributing to the local microenvironment thereby providing a favourable regenerative niche for NMJs formation and maturation.
神经肌肉接头 (NMJ) 研究对于深入了解神经肌肉病理生理学以及开发与 NM 功能障碍相关疾病的新型治疗方法至关重要。在体内，NMJ 周围的微环境通过神经营养和分化因子对 NMJ 的形成和维持产生重大影响，这些因子是由于肌纤维和运动神经元之间的相互作用而分泌的。最近，我们在大鼠胚胎脊髓外植体来源的永生化人成肌细胞和运动神经元的共培养物中，在不含血清和神经营养或生长因子的培养基中，证明了体外功能性 NMJ 的形成。本研究旨在评估在没有外源性神经生长因子的情况下，这种共培养物中功能性 NMJ 是如何建立的。为了研究这个问题，我们使用基于 ELISA 的微阵列比较了共培养物和无神经肌肉培养物中可溶性内源性分泌生长因子的组成。脑源性神经营养因子 (BDNF)、胶质细胞系衍生的神经营养因子 (GDNF)、胰岛素样生长因子结合蛋白-3 (IGFBP-3)、胰岛素样生长因子-1 (IGF-1)、神经营养因子-3 (NT-3)、神经营养因子-4 (NT-4) 和血管内皮生长因子 (VEGF) 这 7 种神经营养因子的水平 (p < 0.05) 在 NMJ 培养物上清液中高于无神经肌肉培养物上清液，表明肌肉和运动神经元之间的相互作用促进了可溶性生长因子的分泌，有助于局部微环境，从而为 NMJ 的形成和成熟提供了有利的再生龛。
