Excretion of Amyloid-β in the Gastrointestinal Tract and Regulation by the Gut Microbiota

作者：Shijing Wu, Li Hu, Jiajing Lin, Kanglan Li, Shicai Ye, Shaoping Zhu, Zhou Liu · 发表于：Journal of Alzheimer s Disease · 年份：2022 · DOI：10.3233/jad-220705 · 被引用次数：4 · 研究领域：Alzheimer's disease research and treatments、Gut microbiota and health、Barrier Structure and Function Studies

BACKGROUND: Amyloid-β (Aβ) is important in the etiology of Alzheimer's disease (AD). Removal of Aβ from the brain is a major strategy for the prevention and treatment of AD. OBJECTIVE: To clarify whether Aβ42 can be cleared by intestinal excretion and whether the gut microbiota (GM) can affect the excretory clearance of Aβ42 in the peripheral blood and intestines. METHODS: Male 8-month-old C57BL6 mice were maintained on either normal chow or received broad-spectrum antibiotics in their drinking water for one week. Sterile saline, fluorescein isothiocyanate (FITC), or FITC-Aβ42 (fluorescein isothiocyanate-labeled amyloid-β42 peptides) was injected 1 h before sampling. Related changes of Aβ42 before and after injection were evaluated. RESULTS: FITC-Aβ42 was injected into mice through the tail vein and could later be detected in feces. Furthermore, the fecal concentrations of FITC-Aβ42 were higher in mice that had been fed antibiotics to alter their GM than in normal mice. However, the FITC-Aβ42 concentrations in blood showed the opposite pattern. CONCLUSION: Aβ42 can be excreted into the intestinal lumen and is regulated by the GM.