1. Metallothionein synthesis increased by Ninjin-yoei-to, a Kampo medicine protects neuronal death and memory loss after exposure to amyloid β1-42
- Author
-
Haruna Tamano, Haruna Tokoro, Daichi Murakami, Rin Tsujimoto, Yuka Nishijima, Erina Tsuda, Satoshi Watanabe, Miki Suzuki, and Atsushi Takeda
- Subjects
Metallothionein ,Amyloid β1-42 ,Alzheimer’s disease ,Zn2+ dysregulation ,Ninjin-yoei-to ,Kampo medicine ,Therapeutics. Pharmacology ,RM1-950 ,Pharmacy and materia medica ,RS1-441 - Abstract
Abstract Background It is possible that increased synthesis of metallothioneins (MTs), Zn2+-binding proteins is linked with the protective effect of Ninjin-yoei-to (NYT) on Zn2+ toxicity ferried by amyloid β1-42 (Aβ1-42). Methods Judging from the biological half-life (18-20 h) of MTs, the effective period of newly synthesized MT on capturing Zn2+ is estimated to be approximately 2 days. In the present paper, a diet containing 3% NYT was administered to mice for 2 days and then Aβ1-42 was injected into the lateral ventricle of mice. Results MT level in the dentate granule cell layer was elevated 2 days after administration of NYT diet, while the administration reduced intracellular Zn2+ level increased 1 h after Aβ1-42 injection, resulting in rescuing neuronal death in the dentate granule cell layer, which was observed 14 days after Aβ1-42 injection. Furthermore, Pre-administration of NYT diet rescued object recognition memory loss via affected perforant pathway long-term potentiation after local injection of Aβ1-42 into the dentate granule cell layer of rats. Conclusion The present study indicates that pre-administration of NYT diet for 2 days increases synthesis of MTs, which reduces intracellular Zn2+ toxicity ferried by extracellular Aβ1-42, resulting in protecting neuronal death in the dentate gyrus and memory loss after exposure to Aβ1-42.
- Published
- 2022
- Full Text
- View/download PDF