Department of Endocrinology, Wuxi People's Hospital Affiliated to Nanjing Medical University , Wuxi , China.
Department of Endocrinology, the First Affiliated Hospital of Nanjing Medical University , Nanjing , China.
Free Radic Res. 2019 Aug;53(8):932-940. doi: 10.1080/10715762.2019.1649670. Epub 2019 Aug 13.
Enteric glial cells (EGCs), one main cell population of the enteric nervous system (ENS), play a major role in regulating intestinal barrier function. toxin B (TcdB) is the major virulence factor produced by and estimated to be toxic to EGCs by inducing cell death, cell cycle arrest, and inflammatory cytokine production; however, the detailed mechanism for such effect is still unclear. In this study, we further evaluated the toxic effect of TcdB on EGCs and the involvement of NADPH oxidases in such process using the rat-transformed EGCs (CRL-2690). The results showed that NOX4 was activated by TcdB in EGCs and functioned as the major factor causing cytotoxicity and cell apoptosis. Mechanically, NOX4-generated HO was the inducer of oxidative stress, Ca homeostasis disorder, and ER stress in EGCs upon TcdB treatment, and NOX4 inhibition protected EGCs against TcdB toxicity via attenuating these dysfunctions. These findings contribute to our understanding of the mechanism by which TcdB affects EGCs and suggest the potential value of NOX4 inhibition for treatment against infection.
肠胶质细胞(EGCs)是肠神经系统(ENS)的主要细胞群之一,在调节肠道屏障功能方面发挥着重要作用。产毒梭菌(Clostridium difficile)产生的肠毒素 B(TcdB)是主要的毒力因子,据估计,它通过诱导细胞死亡、细胞周期停滞和炎症细胞因子产生对 EGCs 有毒性;然而,其详细的作用机制尚不清楚。在这项研究中,我们使用大鼠转化的 EGCs(CRL-2690)进一步评估了 TcdB 对 EGCs 的毒性作用以及 NADPH 氧化酶在此过程中的参与。结果表明,TcdB 激活了 EGCs 中的 NOX4,并且是引起细胞毒性和细胞凋亡的主要因素。在机制上,NOX4 产生的 HO 在 TcdB 处理后是诱导 EGCs 中氧化应激、钙稳态紊乱和内质网应激的因素,而 NOX4 抑制通过减轻这些功能障碍来保护 EGCs 免受 TcdB 毒性。这些发现有助于我们理解 TcdB 影响 EGCs 的机制,并表明 NOX4 抑制在治疗产毒梭菌感染中的潜在价值。