[Modified Kaixin San improves memory and synaptic damage of mice with Alzheimer's disease by modulating αCaMKⅡ-PSD95 protein binding through inhibition of neuroinflammation:a study of mechanism].

Abstract

To investigated the mechanisms underlying the effects of modified Kaixin San(MKXS) on improving memory and synaptic damage of Alzheimer's disease(AD) mouse model with conditional presenilin 1/2 conditional double knockout(PS cDKO). Specifically, 60 PS cDKO mice(3-3.5 months old) and their age-matched wild-type(WT) littermates were randomized into three groups: WT group(n=20), PS cDKO group(n=20), and PS cDKO+MKXS group(n=20). Mice in WT and PS cDKO groups were fed with standard chow and those in PS cDKO+MKXS group were given chow containing MKXS(at 2.55 g·kg~(-1)) for 60 days. Novel object reco-gnition task was employed to detect the recognition memory of mice, and Western blot to detect the protein levels of synapse-associated proteins in the hippocampus(HPC) of mice, such as NR1, NR2 A, NR2 B, p-αCaMKⅡ, tau, and p-tau. Microglial morphology in the HPC CA1 of mice was observed based on immunohistochemistry. Quantitative real time-PCR(qRT-PCR) was employed to detect the mRNA levels of the pro-inflammatory factors and synapse-associated proteins in the HPC of mice, including COX-2, iNOS, IL-1β, IL-6, TNF-α, PSD95, NR1, NR2 A, NR2 B, and MAP2. The protein levels of IL-1β, TNF-α, and IL-6 were tested by enzyme-linked immunosorbent assay(ELISA). The interaction between PSD95 and αCaMKⅡ and between PSD95 and p-αCaMKⅡ was tested by co-immunoprecipitation(Co-IP). The results showed that PS cDKO+MKXS demonstrated significantly higher preference index and recognition index of the new objects, lower protein level of p-tau(ser 396/404) and mRNA levels of COX-2, iNOS, TNF-α, IL-1β, and IL-6 in HPC, higher protein levels of NR1, NR2 A, NR2 B, and p-αCaMKⅡ and mRNA levels of NR1, NR2 A, NR2 B, PSD95, and MAP2, and stronger interaction of αCaMKⅡ with PSD95 and interaction of p-αCaMKⅡ with PSD95 than the PS cDKO group. Immunohistoche-mical staining showed that MKXS inhibited the activation of microglia. In conclusion, MKXS improves memory and synaptic damage in mice with AD by modulating αCaMKⅡ-PSD95 protein binding through inhibition of neuroinflammation.

• Authors: Zhi-Yuan Lu, Chen-Yi Zhao, Guang Yang, Yu-Ting Tong, Zong-Tao Ba, Ahelijiang Reaila, Jian-Mei Yang, Ying Xu
• Journal: Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica (Zhongguo Zhong Yao Za Zhi) Vol. 47 Issue 22 Pg. 6217-6226 (Nov 2022) ISSN: 1001-5302 [Print] China
• PMID: 36471948 (Publication Type: English Abstract, Journal Article)

Chemical References

• kaixin
• Disks Large Homolog 4 Protein
• Tumor Necrosis Factor-alpha
• Cyclooxygenase 2
• Interleukin-6
• RNA, Messenger

Topics

• Animals
• Mice
• Alzheimer Disease (drug therapy, genetics)
• Disks Large Homolog 4 Protein (genetics, metabolism)
• Neuroinflammatory Diseases
• Tumor Necrosis Factor-alpha (metabolism)
• Cyclooxygenase 2 (genetics, metabolism)
• Interleukin-6 (metabolism)
• Protein Binding
• Mice, Knockout
• Hippocampus (metabolism)
• Disease Models, Animal
• RNA, Messenger (metabolism)