促进肠神经系统（ENS）中的成人神经发生可能是治愈肠神经病的潜在治疗方法。肠神经胶质细胞(EGCs)是ENS中最丰富的神经胶质细胞。越来越多的证据表明，在ENS的成年神经发生过程中，EGC可能是提供新神经元的补充来源。在大脑中,已经对星形胶质细胞的神经元转换特性进行了深入的研究，和小分子已经成功地用于诱导星形胶质细胞到神经元的转变。然而,关于ENS中胶质细胞到神经元转换的研究仍然缺乏。在这项研究中,我们使用GFAP-Cre：Rosa-tdTomato小鼠在体内和体外追踪ENS中的神经胶质向神经元的转分化。我们表明，GFAP启动子驱动的tdTomato仅标记了EGC，并且是在成年小鼠ENS中追踪EGC及其后代细胞的合适标记。有趣的是,我们发现RepSox或其他ALK5抑制剂单独在体外诱导EGC有效转分化为神经元.ALK5的敲低进一步证实TGFβR-1/ALK5信号通路在EGC向神经元的转变中起着重要作用。RepSox诱导的神经元为Calbindin和nNOS阳性，并表现出典型的神经元电生理特性。最后,我们表明，施用RepSox（3，10mg·kg-1·d-1，i.g.）2周可显着促进ENS中EGC向神经元的转化，并影响成年小鼠的胃肠道运动。这项研究提供了一种通过小分子化合物将成年小鼠EGCs有效转化为神经元的方法，这可能是胃肠道神经病的一种有希望的治疗策略。
Promoting adult neurogenesis in the enteric nervous system (ENS) may be a potential therapeutic approach to cure enteric neuropathies. Enteric glial cells (EGCs) are the most abundant glial cells in the ENS. Accumulating evidence suggests that EGCs can be a complementary source to supply new neurons during adult neurogenesis in the ENS. In the brain, astrocytes have been intensively studied for their neuronal conversion properties, and small molecules have been successfully used to induce the astrocyte-to-neuron transition. However, research on glia-to-neuron conversion in the ENS is still lacking. In this study, we used GFAP-Cre:Rosa-tdTomato mice to trace glia-to-neuron transdifferentiation in the ENS in vivo and in vitro. We showed that GFAP promoter-driven tdTomato exclusively labelled EGCs and was a suitable marker to trace EGCs and their progeny cells in the ENS of adult mice. Interestingly, we discovered that RepSox or other ALK5 inhibitors alone induced efficient transdifferentiation of EGCs into neurons in vitro. Knockdown of ALK5 further confirmed that the TGFβR-1/ALK5 signalling pathway played an essential role in the transition of EGCs to neurons. RepSox-induced neurons were Calbindin- and nNOS-positive and displayed typical neuronal electrophysiological properties. Finally, we showed that administration of RepSox (3, 10 mg· kg-1 ·d-1, i.g.) for 2 weeks significantly promoted the conversion of EGCs to neurons in the ENS and influenced gastrointestinal motility in adult mice. This study provides a method for efficiently converting adult mouse EGCs into neurons by small-molecule compounds, which might be a promising therapeutic strategy for gastrointestinal neuropathy.
