mTOR Inhibition Mitigates Molecular and Biochemical Alterations of Vigabatrin-Induced Visual Field Toxicity in Mice.
mTOR Inhibition Mitigates Molecular and Biochemical Alterations of Vigabatrin-Induced Visual Field Toxicity in Mice.
复制标题
DOI：
10.1016/j.pediatrneurol.2016.09.016
复制
发表时间：
2017-01
影响因子：
3.8
通讯作者：
Gibson KM
中科院分区：
文献类型：
--
作者：
Vogel KR;Ainslie GR;Schmidt MA;Wisor JP;Gibson KM
γ-乙烯基- γ-氨基丁酸（GABA） （vigabatrin）是一种与视野损害相关的抗癫痫药物和不可逆GABA转氨酶抑制剂，限制了其临床应用。我们试图将摄入维加巴特林引起的视觉诱发电位改变与雷帕霉素（mTOR）通路和GABA受体的转录变化联系起来，以揭示维加巴特林诱导视野丧失的进一步机制。通过渗透泵给小鼠服用Vigabatrin两周以增加GABA水平。检测视觉诱发电位，采集眼球样本，定量逆转录-聚合酶链反应测定基因表达。同样，将人视网膜色素上皮细胞（ARPE19）暴露于vigabatrin并使用mTOR抑制剂处理，以进行mTOR通路分析，并通过显微镜评估细胞器积累的变化。mTOR通路、GABAA/B受体、代谢性谷氨酸（Glu）受体1/6和GABA/谷氨酸转运蛋白转录本的异常表达与维加巴林给药期间的视觉诱发电位变化有关。Rrag基因在小鼠眼细胞和ARPE19细胞中均表达上调。全眼免疫印迹显示，当免疫印迹检测ras相关的鸟苷三磷酸结合d时，200 kDa条带上调3倍以上。ARPE19细胞显微镜观察显示，自噬诱导药物选择性逆转维加巴林诱导的细胞器积累，尤其是Torin 2。在ARPE19细胞中，包括Rrag基因在内的mTOR通路基因表达的变化被Torin 2纠正。我们的研究表明，gaba相关的RRAG和mTOR信号的增强，支持mTOR抑制剂作为一种治疗策略的进一步临床前评估，以潜在地减轻维加巴林诱导的眼部毒性。
Gamma-vinyl–γ-aminobutyric acid (GABA) (vigabatrin) is an antiepileptic drug and irreversible GABA transaminase inhibitor associated with visual field impairment, which limits its clinical utility. We sought to relate altered visual evoked potentials associated with vigabatrin intake to transcriptional changes in the mechanistic target of rapamycin (mTOR) pathway and GABA receptors to expose further mechanisms of vigabatrin-induced visual field loss. Vigabatrin was administered to mice via an osmotic pump for two weeks to increase GABA levels. Visual evoked potentials were examined, eye samples were collected, and gene expression was measured by quantitative reverse transcription-polymerase chain reaction. Similarly, human retinal pigment epithelial cells (ARPE19) were exposed to vigabatrin and treated with mTOR inhibitors for mTOR pathway analysis and to assess alterations in organelle accumulation by microscopy. Dysregulated expression of transcripts in the mTOR pathway, GABAA/B receptors, metabotropic glutamate (Glu) receptors 1/6, and GABA/glutamate transporters in the eye were found in association with visual evoked potential changes during vigabatrin administration. Rrag genes were upregulated in both mouse eye and ARPE19 cells. Immunoblot of whole eye revealed greater than three fold upregulation of a 200 kDa band when immunoblotted for ras-related guanosine triphosphate binding D. Microscopy of ARPE19 cells revealed selective reversal of vigabatrin-induced organelle accumulation by autophagy-inducing drugs, notably Torin 2. Changes in the mTOR pathway gene expression, including Rrag genes, were corrected by Torin 2 in ARPE19 cells. Our studies, indicating GABA-associated augmentation of RRAG and mTOR signaling, support further preclinical evaluation of mTOR inhibitors as a therapeutic strategy to potentially mitigate vigabatrin-induced ocular toxicity.
登录
查看更多内容
GSK3介导的Raptor磷酸化支持氨基酸依赖性MTORC1定向信号传导。
DOI：
10.1042/bj20150404
发表时间：
2015-09-01
期刊：
The Biochemical journal
影响因子：
--
作者：
Stretton C;Hoffmann TM;Munson MJ;Prescott A;Taylor PM;Ganley IG;Hundal HS
通讯作者：
Hundal HS
影响因子：
3.4
作者：
Kara, N. Z.;Toker, L.;Einat, H.
通讯作者：
Einat, H.
影响因子：
--
作者：
Gran P;Cameron-Smith D
通讯作者：
Cameron-Smith D
影响因子：
1.5
作者：
BUTLER, WH;FORD, GP;NEWBERNE, JW
通讯作者：
NEWBERNE, JW
DOI：
10.1523/jneurosci.1283-12.2012
发表时间：
2012-08-15
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience
影响因子：
--
作者：
Weston MC;Chen H;Swann JW
通讯作者：
Swann JW