Soluble tumor necrosis factor-alpha-induced hyperexcitability contributes to retinal ganglion cell apoptosis by enhancing Nav1.6 in experimental glaucoma.
Soluble tumor necrosis factor-alpha-induced hyperexcitability contributes to retinal ganglion cell apoptosis by enhancing Nav1.6 in experimental glaucoma.
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可溶性肿瘤坏死因子-α 诱导的过度兴奋通过增强实验性青光眼中的 Nav1.6 促进视网膜神经节细胞凋亡
DOI：
10.1186/s12974-021-02236-6
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发表时间：
2021-08-21
影响因子：
9.3
通讯作者：
Wang Z
中科院分区：
文献类型：
--
作者：
Cheng S;Wang HN;Xu LJ;Li F;Miao Y;Lei B;Sun X;Wang Z
神经炎症在青光眼的发病机制中起重要作用。肿瘤坏死因子-α（TNF-α）是青光眼中活化的视网膜胶质细胞释放的主要促炎细胞因子。本研究探讨了TNF-α诱导视网膜神经节细胞（RGC）过度兴奋和损伤的机制。采用全细胞膜片钳技术观察视网膜神经节细胞自发放电、诱发动作电位和钠电流的变化。采用玻璃体腔注射TNF-α和慢性高眼压（COH）模型。采用Western blotting、免疫荧光、实时荧光定量PCR和末端脱氧核苷酸转移酶缺口末端标记（TUNEL）技术研究TNF-α对RGCs作用的分子机制。玻璃体内注射可溶性TNF-α可显著增加视网膜节细胞的自发放电频率。当突触传递被阻断时，90%以上的RGCs仍显示自发放电，细胞百分比和放电频率均高于对照组。此外，诱发动作电位的频率也高于对照组。同时注射TNF-α受体1（TNFR 1）抑制剂R7050可消除TNF-α诱导的效应，提示TNF-α可能通过激活TNFR 1直接作用于RGCs，诱导细胞过度兴奋。在从TNF-α注射的视网膜急性分离的RGC中，Na+电流密度上调。在正常大鼠RGCs内灌注TNF-α可模拟此效应，Na+电流激活曲线向超极化方向移动，这是通过p38 MAPK和STAT 3信号通路介导的。进一步分析表明TNF-α选择性上调RGC Na+通道的Nav1.6亚型。与COH大鼠视网膜中的观察结果相似，玻璃体内注射TNF-α可上调总细胞和膜组分中Nav1.6蛋白的表达，NF-κB抑制剂BAY 11-7082可逆转该结果。抑制TNFR 1可阻断TNF-α诱导的RGC凋亡。TNF-α/TNFR 1信号通过选择性上调Nav1.6 Na+通道诱导RGC过度兴奋，从而促进青光眼中的RGC凋亡。
Neuroinflammation plays an important role in the pathogenesis of glaucoma. Tumor necrosis factor-alpha (TNF-α) is a major pro-inflammatory cytokine released from activated retinal glial cells in glaucoma. Here, we investigated how TNF-α induces retinal ganglion cell (RGC) hyperexcitability and injury. Whole-cell patch-clamp techniques were performed to explore changes in spontaneous firing and evoked action potentials, and Na+ currents in RGCs. Both intravitreal injection of TNF-α and chronic ocular hypertension (COH) models were used. Western blotting, immunofluorescence, quantitative real-time polymerase chain reaction (q-PCR), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) techniques were employed to investigate the molecular mechanisms of TNF-α effects on RGCs. Intravitreal injection of soluble TNF-α significantly increased the spontaneous firing frequencies of RGCs in retinal slices. When the synaptic transmissions were blocked, more than 90% of RGCs still showed spontaneous firing; both the percentage of cells and firing frequency were higher than the controls. Furthermore, the frequency of evoked action potentials was also higher than the controls. Co-injection of the TNF-α receptor 1 (TNFR1) inhibitor R7050 eliminated the TNF-α-induced effects, suggesting that TNF-α may directly act on RGCs to induce cell hyperexcitability through activating TNFR1. In RGCs acutely isolated from TNF-α-injected retinas, Na+ current densities were upregulated. Perfusing TNF-α in RGCs of normal rats mimicked this effect, and the activation curve of Na+ currents shifted toward hyperpolarization direction, which was mediated through p38 MAPK and STAT3 signaling pathways. Further analysis revealed that TNF-α selectively upregulated Nav1.6 subtype of Na+ currents in RGCs. Similar to observations in retinas of rats with COH, intravitreal injection of TNF-α upregulated the expression of Nav1.6 proteins in both total cell and membrane components, which was reversed by the NF-κB inhibitor BAY 11-7082. Inhibition of TNFR1 blocked TNF-α-induced RGC apoptosis. TNF-α/TNFR1 signaling induces RGC hyperexcitability by selectively upregulating Nav1.6 Na+ channels, thus contributing to RGC apoptosis in glaucoma.
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影响因子：
4.6
作者：
De Groef L;Salinas-Navarro M;Van Imschoot G;Libert C;Vandenbroucke RE;Moons L
通讯作者：
Moons L
影响因子：
4.8
作者：
Bai, Yujing;Dergham, Pauline;Saragovi, H. Uri
通讯作者：
Saragovi, H. Uri
DOI：
10.1093/brain/awaa208
发表时间：
2020-08-01
期刊：
Brain : a journal of neurology
影响因子：
--
作者：
Chen, Lubin;Huang, Jianying;Dib-Hajj, Sulayman D
通讯作者：
Dib-Hajj, Sulayman D
影响因子：
4.2
作者：
Huang, Yangliang;Zang, Ying;Zhong, Yi
通讯作者：
Zhong, Yi
DOI：
10.1016/s0169-328x(97)00187-3
发表时间：
1997-10-15
期刊：
MOLECULAR BRAIN RESEARCH
影响因子：
--
作者：
Fjell, J;DibHajj, S;Waxman, SG
通讯作者：
Waxman, SG