Kurose Takahiro, Sugano Eriko, Sugai Akihisa, Shiraiwa Raki, Kato Mariyo, Mitsuguchi Yoko, Takai Yoshihiro, Tabata Kitako, Honma Yoichi, Tomita Hiroshi
Rohto Pharmaceutical Co., Ltd., 6-5-4 Kunimidai, Kizugawa, Kyoto 619-0216, Japan.
Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan.
Int J Ophthalmol. 2019 Aug 18;12(8):1231-1237. doi: 10.18240/ijo.2019.08.01. eCollection 2019.
To evaluate the neuroprotective effect of a dietary supplement (ClearVision EX; CV) against glutamate-induced excitotoxicity in retina.
We evaluated the protective effects CV on glutamate-induced cell toxicity of an immortalized mouse hippocampal cell line (HT-22) and N-methyl-D-aspartate (NMDA) induced retinal injury . Once-daily oral administration of CV or vehicle (5% Arabic gum) was started the day before the NMDA injection and continued until the end of the study. Electroretinograms (ERGs) were recorded to evaluate the retinal function at 2d after NMDA injection. Furthermore, a histological evaluation, Western blot analysis, and immunohistochemistry were performed for assessing the signal transduction pathway.
HT-22 cell death was induced by the addition of glutamate and co-incubation with CV protected against it. Oral administration of CV inhibited the decrease in scotopic threshold response amplitudes induced by the intravitreal injection of NMDA and those of the thickness of the inner retinal layer in the histological evaluation. The increased phosphorylated levels of extracellular signal-regulated kinase (ERK) but not cAMP response element binding protein (CREB) or Akt were observed 1h after NMDA injection in both the vehicle- and CV-treated rats; however, pERK activation was no more upregulated at 3h after NMDA injection. pERK upregulation was observed in Müller cells.
CV shows a protective effect against both glutamate-induced HT-22 cell death and NMDA-induced retinal damage. pERK upregulation in the Müller cells plays a key role in the protective effect of CV against glutamate-induced retinal toxicity.
评估一种膳食补充剂（ClearVision EX；CV）对视网膜谷氨酸诱导的兴奋性毒性的神经保护作用。
我们评估了CV对永生化小鼠海马细胞系（HT - 22）谷氨酸诱导的细胞毒性以及N - 甲基 - D - 天冬氨酸（NMDA）诱导的视网膜损伤的保护作用。在NMDA注射前一天开始每日一次口服CV或赋形剂（5%阿拉伯胶），并持续至研究结束。在NMDA注射后2天记录视网膜电图（ERG）以评估视网膜功能。此外，进行了组织学评估、蛋白质印迹分析和免疫组织化学以评估信号转导途径。
添加谷氨酸可诱导HT - 22细胞死亡，与CV共同孵育可起到保护作用。口服CV可抑制玻璃体内注射NMDA诱导的暗视阈值反应幅度降低以及组织学评估中视网膜内层厚度的降低。在NMDA注射后1小时，在给予赋形剂和CV处理的大鼠中均观察到细胞外信号调节激酶（ERK）磷酸化水平升高，但环磷酸腺苷反应元件结合蛋白（CREB）或Akt未升高；然而，在NMDA注射后3小时，pERK激活未进一步上调。在Müller细胞中观察到pERK上调。
CV对谷氨酸诱导的HT - 22细胞死亡和NMDA诱导的视网膜损伤均具有保护作用。Müller细胞中pERK上调在CV对谷氨酸诱导的视网膜毒性的保护作用中起关键作用。
