Development of vesicular glutamate transnporter inhibitors

囊泡谷氨酸转运蛋白抑制剂的开发

• 批准号: 16510174
• 负责人: SHIMAMOTO Keiko
• 金额: $ 2.62万
• 依托单位: Suntory Institute for Bioorganic Research
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16510174/
• 关键词: glutamate; transporter; synaptic vesicles; inhibitor; trans-ACPD; esterification; シナプス小胞

Glutamate is a major excitatory neurotransmitter in mammalian central nervous systems and is linked to higher brain functions such as memory and learning. Glutamate is concentrated into synaptic vesicles through Vesicular Glutamate Transporters (VGLUTs) and is stocked in vesicles in nerve endings. As known inhibitors also show affinity for glutamate receptors and synaptic glutamate transporters (EAATs), selective inhibitors for VGLUTs have been required. It would be important that inhibitors permeate plasma membrane to inhibit VGLUTs inside neurons. In order to improve selectivity for VGLUTs, potency, and cell membrane permeability, we synthesized novel trans-ACPD derivatives. First, we synthesized methyl analogs to examine the position and stereochemistry of a substituent. Among them, 5R-methyl analog showed inhibition of glutamate uptake into vesicles. Thus, we tried to introduce a hydroxyl analog and ether analogs to examine the effects of a substituent. Similar to the synthetic scheme of methyl analogs, alkylidenecarbene prepared from the corresponding ketone was applied for the benzyloxy analog. However, benzyl position reacted to give an ether ring instead of the five membered-ring cyclization. We examine other protective groups on the hydroxyl group to overcome this problem. Furthermore, to improve the cell membrane permeability, γ-carboxyl group was converted into methyl ester (ACPD-OMe). ACPD-OMe didn't inhibit the transport of glutamate into the isolated vesicles, while it decreased the glutamate transport using synaptosomes. On the other hand, trans-ACPD didn't affect the glutamate transport when synaptosomes were used. ACPD-OMe would be converted to trans-ACPD by enzyme after membrane permeation and, then, inhibit VGLUTs. These results demonstrate that the modification of carboxylic acid is useful for the improvement of cell membrane permeability and development of novel type of VGLUT inhibitors.

谷氨酸是哺乳动物中枢神经系统中一种主要的兴奋性神经递质，与记忆和学习等高级大脑功能有关。谷氨酸通过囊泡谷氨酸转运体(VGLUT)聚集到突触小泡中，并储存在神经末梢的小泡中。由于已知的抑制剂也对谷氨酸受体和突触谷氨酸转运体(EAATs)具有亲和力，因此需要针对VGLUT的选择性抑制剂。抑制细胞内VGLUT的重要途径是抑制细胞质膜。为了提高对VGLUT的选择性、效价和细胞膜的通透性，我们合成了新型的反式ACPD衍生物。首先，我们合成了甲基类似物来研究取代基的位置和立体化学。其中，5R-甲基类似物对囊泡摄取谷氨酸有抑制作用。因此，我们尝试引入羟基类似物和乙醚类似物来考察取代基的影响。类似于甲基类似物的合成方案，将由相应的酮制备的亚烷基卡宾应用于苄氧基类似物。但是，五元环上的环化反应不同于五元环的环化反应，而是由苄基位置反应生成了醚环。我们研究了羟基上的其他保护基团来克服这个问题。此外，为了提高细胞膜的通透性，将γ-羧基转化为甲酯(ACPD-OME)。Acpd-ome不抑制谷氨酸向小泡的转运，但减少了谷氨酸通过突触小体的转运。另一方面，使用突触体时，反式-acpd不影响谷氨酸的转运。ACPD-OME在膜渗透后被酶转化为反式ACPD，从而抑制VGLUT。这些结果表明，羧酸的修饰有助于提高细胞膜的通透性和开发新型的VGLUT抑制剂。

项目成果

Elucidation of glutamate transporter functions using selective inhibitors.

使用选择性抑制剂阐明谷氨酸转运蛋白功能。

• 发表时间: 2006
• 期刊: Central Nervous System Agents in Medicinal Chemistry 6・1
• 作者: 島本啓子;茂里康
• 通讯作者: 茂里康

抑制性神経伝達物質トランスポーターの薬理学

抑制性神经递质转运蛋白的药理学

• 发表时间: 2006
• 期刊: 日本薬理学会誌 127・4
• 作者: 茂里康;島本啓子
• 通讯作者: 島本啓子

Glial glutamate transporters maintain one-to-one relationship at the climbing fiber-Purkinje cell synapses by preventing glutamate spillover

胶质细胞谷氨酸转运蛋白通过防止谷氨酸溢出来维持攀爬纤维-浦肯野细胞突触的一对一关系

• 发表时间: 2006
• 期刊: The Journal of Neuroscience 26
• 作者: Y.Okada^*;Y.Sano;T.Kaneko;I.Abe;H.Noguchi;K.Ito;K.Shimamoto;O.Boudker;Y.Takayasu
• 通讯作者: Y.Takayasu

Coupling substrate and ion hinding to extracellular gate of a sodium-dependent aspartate transporter

耦合底物和离子阻碍钠依赖性天冬氨酸转运蛋白的细胞外门

• 发表时间: 2007
• 期刊: Nature 445
• 作者: Y.Okada^*;Y.Sano;T.Kaneko;I.Abe;H.Noguchi;K.Ito;K.Shimamoto;O.Boudker
• 通讯作者: O.Boudker

興奮性神経伝達の恒常性維持-グルタミン酸トランスポーターの役割解明を目指して.

维持兴奋性神经传递的稳态 - 旨在阐明谷氨酸转运蛋白的作用。

• 发表时间: 2005
• 期刊: 神経研究の進歩 49
• 作者: Y.Okada^*;Y.Sano;T.Kaneko;I.Abe;H.Noguchi;K.Ito;K.Shimamoto;O.Boudker;Y.Takayasu;D.B.Re;K.Shimamoto;茂里 康;S.Tsukada;H.Koyama;H.S.Waagepetersen;L.Shachnai;島本 啓子
• 通讯作者: 島本 啓子