Generation and Characterization of a Novel Knockin Mouse Model Expressing PSEN1 D385A: Implications for Investigating Herbal Drug Effects in γ-Secretase Activity
Affiliations:
School of Life Sciences, School of Acupuncture-Moxibustion and Tuina, School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
Correspondence:
[*]
Qian Hua, School of Life Sciences, Beijing University of Chinese Medicine, E-mail: huaq@bucm.edu.cn; PhD Yan Tan, School of Life Sciences, Beijing University of Chinese Medicine, E-mail: yantan@bucm.edu.cn.
Note: [1] These authors contributed equally to this work.
Abstract: Background:Presenilin (PSEN, PS) is essential for γ-secretase function, and mutations can disrupt amyloid-β (Aβ) production in familial Alzheimer’s disease. Targeting γ-secretase is complex due to its broad involvement in physiological processes. Objective:Our aim was to create a novel knockin (KI) mouse model expressing PSEN1 D385A mutation and investigate the efficacy of a Geniposide and Ginsenoside Rg1 combination (NeuroProtect modified formula, NP-2) in restoring γ-secretase activity. Methods:Using gene manipulation, we established the PS1 D385A KI mouse model and confirmed the mutation, mRNA, and protein levels using Southern blotting, northern blotting, and western blotting, respectively. In vitro γ-secretase assay was conducted to measure γ-secretase activity, while histological analyses examined neurogenesis effects. NP-2 administration evaluated its impact on γ-secretase activity. Results:The PS1 D385A KI homozygotes displayed severe cerebral hemorrhage, postnatal lethality, developmental disorders, reduced proliferation of neural progenitor cells, and disrupted γ-secretase function. The mutation abolished PS1 protein self-shearing, leading to compromised γ-secretase activity. NP-2 intervention effectively restored γ-secretase activity in the heterozygous mice. Conclusions:PS1 D385A mutant disrupted PS1 protein self-cleaving, impairing γ-secretase activity in KI mice. NP-2 restored γ-secretase function, offering potential for novel AD treatment strategies despite the challenges posed by γ-secretase’s complex role in physiological processes.
