Hei Xiaoyaosan Ameliorates Cognitive Impairment in Rat Model of Alzheimer's Disease by Clearing Peripheral Aβ via AMPK/SREBP2/PCSK9/LRP-1 Signaling Pathway
10.13422/j.cnki.syfjx.20260740
- VernacularTitle:黑逍遥散调控AMPK/SREBP2/PCSK9/LRP-1信号通路清除外周循环Aβ改善AD大鼠的认知障碍
- Author:
Zifan NIE
1
;
Yingchuan MA
1
;
Wenli PEI
1
;
Yumei HAN
1
;
Jiao YANG
1
;
Ruixue JIN
1
;
Qian WANG
1
;
Huping WANG
1
Author Information
1. Gansu University of Chinese Medicine， Lanzhou 730000，China
- Publication Type:Journal Article
- Keywords:
Alzheimer's disease;
Hei Xiaoyaosan;
peripheral amyloid-β （Aβ） clearance;
adenosine 5'-monophosphate-activated protein kinase （AMPK）/sterol regulatory element-binding protein 2 （SREBP2）/proprotein convertase subtilisin/kexin type 9 （PCSK9）/low-density lipoprotein receptor-related protein 1 （LRP-1） signaling pathway
- From:
Chinese Journal of Experimental Traditional Medical Formulae
2026;32(22):61-73
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the mechanism of Hei Xiaoyaosan （HXS） in ameliorating cognitive impairment in the rat model of Alzheimer's disease （AD） by regulating the adenosine 5'-monophosphate-activated protein kinase （AMPK）/sterol regulatory element-binding protein 2 （SREBP2）/proprotein convertase subtilisin/kexin type 9 （PCSK9）/low-density lipoprotein receptor-related protein 1 （LRP-1） signaling pathway to clear amyloid-β （Aβ） from the peripheral circulation. MethodsNinety 8-week-old specific pathogen-free （SPF）-grade male Sprague-Dawley （SD） rats were acclimatized for 1 week. After acclimatization， 10 rats were randomly selected as the blank control group， and the remaining 80 rats were prepared for surgical modeling. Among the 80 rats for modeling， 70 were anesthetized and injected with 1 μL of amyloid-β1-42 （Aβ1-42） solution into the bilateral hippocampal CA1 region for the modeling of AD， and the remaining 10 were assigned to the sham operation group， which received an injection of 1 μL normal saline at the same anatomical site. The successfully modeled rats were randomly assigned into 6 groups （n=10 per group）： a model group， a donepezil hydrochloride group， an acadesine （AICAR， an AMPK agonist） group， and high-， medium-， and low-dose HXS groups. After 42 consecutive days of administration intervention， the Morris water maze test and T-maze test were performed to evaluate the learning and memory abilities of rats. Fluoro-Jade B （FJB） staining was conducted to observe pathological changes of neurons in the rat hippocampus， and thioflavin S staining to quantify the area of Aβ deposition in the hippocampal region. Immunofluorescence double staining （IF-DS） was performed to detect the expression of LRP-1 and Aβ signals in the liver tissue. Enzyme-linked immunosorbent assay （ELISA） was employed to measure the levels of Aβ1-42 and soluble LRP-1 （sLRP-1） in the serum. Western blot was performed to determine the protein levels of AMPK， phosphorylated AMPK （p-AMPK）， SREBP2， PCSK9， and LRP-1 in the liver tissue. Real time polymerase chain reaction（Real-time PCR） was adopted to assess the mRNA levels of AMPK， SREBP2， PCSK9， and LRP-1 in the liver tissue. ResultsCompared with the blank control group， the model group showed increased total swimming distance on day 6 and path length in the target quadrant on day 7 （P<0.01）， a decreased correct alternation rate in the T-maze test （P<0.01）， disarrangement of hippocampal neurons， increased FJB-positive cells （P<0.01）， enlarged area of Aβ deposition （P<0.01）. reduced LRP-1 fluorescence signals and enhanced Aβ fluorescence signals in the liver tissue （P<0.01）， elevated serum level of Aβ1-42， declined serum level of sLRP-1 （P<0.01）， downregulated protein levels of p-AMPK and LRP-1 as well as mRNA levels of AMPK and LRP-1， and upregulated protein and mRNA levels of SREBP2 and PCSK9 in the liver tissue （P<0.01）. Compared with the model group， the high-dose HXS group， donepezil hydrochloride group， and AICAR group exhibited reduced total swimming distance and target quadrant path length （P<0.05， P<0.01）， an increased correct alternation rate in the T-maze test （P<0.05）， decreased FJB-positive cells （P<0.01）， reduced Aβ deposition （P<0.01） in the hippocampal tissue， enhanced LRP-1 signals and weakened Aβ signals in the liver tissue （P<0.01）， a declined serum level of Aβ1-42 and an elevated serum level of sLRP-1 （P<0.01）， upregulated protein levels of p-AMPK and LRP-1 as well as mRNA levels of AMPK and LRP-1， and downregulated protein and mRNA levels of SREBP2 and PCSK9 in the liver tissue （P<0.01）. ConclusionHei Xiaoyaosan can regulate the AMPK/SREBP2/PCSK9/LRP-1 signaling pathway to enhance the clearance of peripheral Aβ by the liver tissue and reduce Aβ deposition in the brain， thereby improving the learning and memory abilities of AD rats.
