PubMedJournal of ethnopharmacology2026-09-08
Bushen-Yizhi formula promotes neurogenesis and ameliorates cognitive impairment by activating ST8Sia Ⅱ/Ⅳ-PSA-NCAM pathway in ibotenic acid induced mice.
Zheng Jingjing J, Tan Qiwen Q, Liu Guoqing G, Xie Ruiye R et al.
Bushen-Yizhi formula (BSYZ), a traditional Chinese herbal prescription, has been widely used to treat kidney deficiency syndrome and alleviate cognitive impairment associated with Alzheimer's disease (AD). Loss of polysialylation of the neural cell adhesion molecule (PSA-NCAM) is closely associated with cognitive dysfunction. However, whether BSYZ regulates PSA-NCAM polysialylation and the underlying mechanisms remain unclear.
This study aimed to investigate whether BSYZ promotes hippocampal neurogenesis and ameliorates cognitive impairment through activation of the ST8Sia II/IV-PSA-NCAM pathway.
An AD-like mouse model was established by bilateral ibotenic acid (IBO) injections into the basal nuclei of C57BL/6 mice. Animals were randomly assigned to five groups: control, model, low- BSYZ (1.46 g/kg), high-dose BSYZ (5.84 g/kg), and donepezil (3 mg/kg). Cognitive function was evaluated using the open field test (OFT), novel object recognition test (NORT), and Morris water maze (MWM). Hippocampal PSA-NCAM expression was assessed by immunofluorescence staining and further investigated using proteomic analysis combined with network pharmacology. PSA-NCAM-associated polysialic acid levels were quantified by hydrochloric acid hydrolysis followed by 4,5-methylenedioxy-1,2-phenylenediamine dihydrochloride (DMB) derivatization coupled with mass spectrometry. The mRNA and protein expression levels of α-2,8-sialyltransferase II and IV (ST8Sia II/IV) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting. Hippocampal neurogenesis was evaluated by immunofluorescence double-labeling. The bioactive compounds targeting ST8Sia II/IV were identified using HPLC-Q-TOF MS/MS, followed by molecular docking and molecular dynamics simulations to predict their binding affinities.
The IBO-induced mouse model exhibited significant cognitive deficits, confirming successful model establishment. Behavioral assessments demonstrated that both low- and high-dose BSYZ significantly improved learning and memory performance. Proteomic analysis and immunofluorescence staining revealed that BSYZ markedly increased hippocampal PSA-NCAM expression (**P < 0.01, n = 5). Quantitative analysis further showed that PSA-NCAM-associated polysialic acid levels increased by 78% (*P < 0.05, n = 5) and 102% (**P < 0.01, n = 5) following low- and high-dose BSYZ treatment. BSYZ significantly increased the number of PSA-NCAM+/DCX+ cells in the hippocampal dentate gyrus (*P < 0.05), accompanied by significant increases in Nestin+/BrdU+ (*P < 0.05), DCX+/BrdU+ (**P < 0.01), and NeuN+/BrdU+ (**P < 0.01) double-positive cells, indicating enhanced neurogenesis and neuronal maturation. Furthermore, BSYZ significantly upregulated both the mRNA and protein expression of ST8Sia II (**P < 0.01) and ST8Sia IV (**P < 0.01) in the hippocampus. HPLC-Q-TOF MS/MS, molecular docking, and molecular dynamics simulations identified isoimperatorin as a major active constituent of BSYZ with strong binding affinity toward both ST8Sia II/IV, exhibiting docking energies of -8.7 and -7.6 kcal/mol, respectively (n = 3, RSD < 2%).
Our study demonstrates BSYZ promotes hippocampal neurogenesis to ameliorate cognitive impairment by activating ST8Sia II/IV-PSA-NCAM pathway. These findings provide mechanistic evidence supporting the therapeutic potential of BSYZ for AD treatment.
