OBJECTIVES: To investigate the protective mechanism of quercetin, the core component of Zuo Gui Wan, against Alzheimer's disease through the PI3K/AKT signaling pathway, based on network pharmacology, molecular docking, and cell experi-ments. METHODS: The active components of Zuo Gui Wan were identified by searching TCMSP, PubChem, Swiss Target Prediction, and BATMAN-TCM databases, and their potential targets were predicted. The target information was standardized using Uniprot, and Alzheimer's disease-related target genes were obtained from Drugbank, GeneCards, and OMIM. The intersection of these datasets was used to identify the potential targets of Zuo Gui Wan for treating Alzheimer's disease. Gene Ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed. The protein-protein interaction (PPI) network of potential targets was visualized using Cytoscape 3.10.1 software and the STRING database. The key active compounds and core potential targets for treating Alzheimer's disease with Zuo Gui Wan were identified through calculation. Based on the enrichment analysis results and literature, quercetin and the PI3K/AKT pathway were selected for verification. Molecular docking and binding ability prediction between quercetin and the core target AKT were performed using CB-Dock2, and visualization was conducted with AutoDock and PyMOL software. Finally, Aβ_1-42-induced HT-22 mouse hippocampal neuronal cells were used to construct an Alzheimer's disease cell model. Quercetin, the PI3K inhibitor LY294002, and the activator EGF were used as interventions. The groups were divided as follows: Control, Aβ_1-42, Aβ_1-42+Quercetin 2.5 μM, Aβ_1-42+Quercetin 5 μM, Aβ_1-42+Quercetin 10 μM, Aβ_1-42+EGF, and the PI3K/AKT modulation group: Control, LY294002, LY294002+Quercetin 10 μM, LY294002+EGF. CCK-8 assays were performed to detect cell viability, while JC-1, Calcein AM-PI, and Hoechst staining were used to assess cell apoptosis. Western blotting was employed to detect the expression of relevant target proteins. RESULTS: Network pharmacology and cell experiments collectively demonstrate that the key active ingredient of Zuo Gui Wan, quercetin, targets core proteins such as AKT1 and GSK3β through a network-based approach, significantly enriching the PI3K/AKT pathway. Molecular docking results indicate that quercetin has a strong binding affinity with AKT. Experimental validation in the Aβ_1-42 oligomer-induced HT-22 model reveals that quercetin significantly activates the PI3K/AKT signaling pathway, which is inhibited by Aβ_1-42 oligomers, as well as Bcl-2 protein expression. It also suppresses the expression of Cleaved Caspase 3/Caspase 3, BAX, and Cytochrome C proteins. JC-1, Hoechst 33342, and Calcein AM-PI staining results further show that quercetin can significantly alleviate apoptosis induced by Aβ_1-42 oligomers in HT-22 cells. Treatment with the PI3K inhibitor LY294002 in HT-22 cells leads to reduced cell viability and decreased expression of p-AKT/AKT and Bcl-2 proteins, while increasing the expression of Cleaved Caspase 3/Caspase 3, BAX, and Cytochrome C proteins. Additionally, apoptosis levels increase as observed in JC-1, Hoechst 33342, and Calcein AM-PI staining, all of which can be reversed by quercetin and the PI3K agonist EGF. CONCLUSIONS Quercetin, the key active ingredient of Zuo Gui Wan, exerts its protective effects against Alzheimer's disease by regulating the PI3K/AKT signaling pathway, inhibiting neuronal cell damage and apoptosis.

Objective This study aimed to explore the differences in global and local brain network topological properties between deficient pattern(DP)and excess pattern(EP)of mild vascular cognitive impairment caused by subcortical small vessel disease based on graph theory network.Methods Patients were recruited prospectively and were classified with DP and EP subtype.The global small-world topological attributes and local nodes were calculated for the comparison of DP,EP,and healthy controls(CN)using the GRETNA platform.Results The three groups all had small-world attributes,but only the patients in EP had a significantly lower small world attribute δ in the range of 0.05-0.26 than the control group(P<0.05).The node efficiency and node strength indicators of multiple brain region were able to significantly distinguish the DP group from the EP group.However,there was no positive brain region in the node efficiency of the DP patients(P>0.05),and only a few brain regions showed increased node strength efficiency(P<0.05).Conclusion The results indicate that the syndrome of DP and EP have significantly different neuroimaging phenotypes,providing a basis for further research of biological classification based on Chinese Medicine syndromes.

To produce high-affinity monoclonal antibodies against pesticide imidacloprid, we synthesized the haptens 1-[(6-Carboxylethylthio-3-pyridinyl) methyl] -N-nitro-imidazolidinimine (named as H1) and 1-[(6-Chloro-3-pyridinyl) methyl]-3-carboxylpropyl-N-nitro-2-imidazolidinimine (termed as H2). And then the haptens were coupled to bovine serum albumin (BSA) and ovalbumin (OVA) for immunogen (H1-BSA) and coating antigen (H2-OVA) respectively by NHS ester method. BALB/c mice were immunized with H1-BSA conjugate. We obtained two hybridoma cell lines 2F11/A9 and 2G6/G12 secreting antibody specific for imidacloprid from the conventional hybridoma technology. The result showed that the subtypes of obtained monoclonal antibodies were IgG3 and IgG1, respectively, and the titers of ascites were up to 1:128 000. The indirect competitive ELISA indicated the IC50 values of 5.3 and 28.3 ng/mL with detection limits of 1.1 ng/mL and 7.7 ng/mL, respectively. Two monoclonal antibodies had no apparent cross reactivity with six analogous compounds. Thus, two prepared monoclonal antibodies had a very high affinity and specificity, and it could be used to develop ELISA for rapid determination of imidacloprid residue and laid a solid foundation for research and development of products for immunoassay.
Animals ; Antibodies, Monoclonal ; biosynthesis ; Antibody Specificity ; Hybridomas ; metabolism ; Imidazoles ; immunology ; Insecticides ; immunology ; Mice ; Mice, Inbred BALB C ; Neonicotinoids ; Nitro Compounds ; immunology