Department of Cellular Biophysics, Graduate School of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan.
Cells. 2023 Jul 17;12(14):1867. doi: 10.3390/cells12141867.
To investigate the roles of calcineurin (CN) in glial cells, we previously generated conditional knockout (CKO) mice lacking in glial cells. Because these CKO mice showed dysfunction and inflammation of the small intestine in addition to growth impairment and postweaning death, we have focused on enteric glial cells (EGCs) in the small intestine. In this study, we examined the effects of deficiency on the proliferation and survival of EGCs and the expression and secretion of EGC-derived substances in culture to reveal the mechanisms of how deficiency leads to dysfunction and inflammation of the small intestine. In primary myenteric cultures of the small intestine, EGCs from the CKO mice showed reduced proliferation and increased apoptosis compared with EGCs from control mice. In purified EGC cultures from the CKO mice, Western blot analysis showed increased expression of S100B, iNOS, GFAP, and GDNF, and increased phosphorylation of NF-κB p65. In the supernatants of purified EGC cultures from the CKO mice, ELISA showed reduced secretion of TGF-β1. In contrast, GDNF secretion was not altered in purified EGC cultures from the CKO mice. Furthermore, treatment with an S100B inhibitor partially rescued the CKO mice from growth impairment and postweaning death in vivo. In conclusion, deficiency leads to reduced proliferation and increased apoptosis of EGCs and abnormal expression and secretion of EGC-derived substances, which may contribute to dysfunction and inflammation of the small intestine.
为了研究钙调神经磷酸酶（CN）在神经胶质细胞中的作用，我们之前生成了条件性敲除（CKO）小鼠，使其在神经胶质细胞中缺失。由于这些 CKO 小鼠除了生长受损和断奶后死亡外，还表现出小肠功能障碍和炎症，因此我们专注于小肠中的肠神经胶质细胞（EGC）。在这项研究中，我们研究了 缺失对 EGC 增殖和存活以及 EGC 衍生物质表达和分泌的影响，以揭示 缺失如何导致小肠功能障碍和炎症的机制。在小肠的初级肌间培养物中，与来自对照小鼠的 EGC 相比，来自 CKO 小鼠的 EGC 显示出增殖减少和凋亡增加。在来自 CKO 小鼠的纯化 EGC 培养物中，Western blot 分析显示 S100B、iNOS、GFAP 和 GDNF 的表达增加，NF-κB p65 的磷酸化增加。在来自 CKO 小鼠的纯化 EGC 培养物的上清液中，ELISA 显示 TGF-β1 的分泌减少。相比之下，来自 CKO 小鼠的纯化 EGC 培养物中 GDNF 的分泌没有改变。此外，用 S100B 抑制剂处理可部分挽救 CKO 小鼠体内的生长受损和断奶后死亡。总之， 缺失导致 EGC 增殖减少和凋亡增加以及 EGC 衍生物质的异常表达和分泌，这可能导致小肠功能障碍和炎症。
