Tetrahydroalstonine possesses protective potentials on palmitic acid stimulated SK-N-MC cells by suppression of Aß1-42 and tau through regulation of PI3K/Akt signaling pathway.

Alzheimer's disease (AD) is the most common neurodegenerative disease. The morbidity of Alzheimer's disease is currently on the rise worldwide, but no effective treatment is available. Cornus officinalis is an herb and edible plant used in traditional Chinese medicine, whose extract has neuroprotective properties. In this investigation, we endeavored to refine a systems pharmacology strategy combining bioinformatics analysis, drug prediction, network pharmacology, and molecular docking to screen tetrahydroalstonine (THA) from Cornus officinalis as a therapeutic component for AD. Subsequent in vitro experiments were validated using MTT assay, Annexin V-PI flow cytometry, Western blotting, and immunofluorescence analysis. In Palmitate acid-induced SK-N-MC cells, THA restored the impaired PI3K/AKT signaling pathway, regulated insulin resistance, and attenuated BACE1 and GSK3ß activity. In addition, THA significantly reduced cell apoptosis rate, down-regulated relative levels of p-JNK/JNK, Bax/Bcl-2, cytochrome C, active caspase-3 and caspase-3, and attenuated Palmitate acid-induced Aß1-42 and Tau generation. THA may regulate the phenotype of AD and reduce cell apoptosis by modulating the PI3K/AKT signaling pathway. This systematic analysis provides new ramifications concerning the therapeutic utility of tetrahydroalstonine for AD.

Network pharmacology analysis and experimental validation of Anemarrhenae Rhizoma in treating Alzheimer's disease. / çŸ¥æ¯æ²»ç–—é˜¿å°”èŒ¨æµ·é»˜ç— ç½‘ç»œè¯ç†å­¦ç ”ç©¶åŠå®žéªŒéªŒè¯.

OBJECTIVES: To explore the mechanism of Anemarrhenae Rhizoma in treatment of Alzheimer's Disease (AD). METHODS: The active ingredients and targets of Anemarrhenae Rhizoma for treatment of AD were screened with network pharmacology methods, the protein-protein interaction (PPI) network was constructed and the core targets were analyzed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enriching analysis was performed. The peripheral blood lymphocytes were extracted and lymphoblastoid cell lines (LCL) were constructed and an in vitro cell model of LCL-SKNMC was established. MTT and CCK-8 methods were used to quantify SKNMC/LCL cells, 2 ´, 7 ´-dichlorodihydrofluorescein diacetate (DCFH-DA) probe was used to detect reactive oxygen species (ROS), and immunofluorescence staining was used to detect the generation of Aß1-42 in a co-cultured model. Western blotting was used to detect protein expression in the co-culture model. The lifespan of N2 nematodes was observed under oxidative stress, normal state, and heat stress; ROS generated by N2 nematodes was detected by DCFH-DA probes. The paralysis time of CL4176 N2 nematodes was evaluated by paralysis assay, and Aß deposition in the pharynx was detected by Thioflavin S staining. RESULTS: Through network pharmacology, 15 potential active ingredients and 103 drug-disease targets were identified. PPI analysis showed that the Anemarrhenae Rhizoma might play anti-AD roles through albumin, Akt1, tumor necrosis factor, epidermal growth factor receptor (EGFR), vascular endothelial growth factor A (VEGFA), mammalian target of rapamycin (mTOR), amyloid precursor protein (APP) and other related targets. KEGG analysis showed that the pharmacological effects of Anemarrhenae Rhizoma might involve the biological processes of Alzheimer's disease, endocrine resistance, insulin resistance; and neuroactive ligand-receptor interaction, phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway, calcium signaling pathway, AGE-RAGE signaling pathway in diabetes complications, neurotrophic factor signaling pathway and others. The in vitro cell experiments showed that Anemarrhenae Rhizoma was able to reduce the production of ROS and Aß1-42 (both P<0.01), inhibit the expression of ß-secretase 1 (BACE1), APP and Aß1-42 proteins (all P<0.05), up-regulate the expression of p-PI3K/PI3K, p-AKT/AKT, p-GSK3ß/GSK3ß in SKNMC cells (all P<0.05). The in vivo studies further confirmed that Anemarrhenae Rhizoma prolonged the lifespan of C. elegans under stress and normal conditions, reduced the accumulation of ROS and the toxicity of Aß deposition. CONCLUSIONS: Anemarrhenae Rhizoma may reduce the production of Aß in AD and inhibit its induced oxidative stress, which may be achieved by regulating the PI3K/Akt/GSK-3ß pathway.

Harpagide alleviate neuronal apoptosis and blood-brain barrier leakage by inhibiting TLR4/MyD88/NF-κB signaling pathway in Angiotensin II-induced microglial activation in vitro.

Angiotensin II, the effector peptide of the renin-angiotensin system, is not only a pivotal peptide implicated in the regulation of blood pressure but also a key mediator of the inflammatory processes that play an important role in the pathology of hypertension-related cSVD. Harpagide is the major bioactive constituent of Scrophulariae Radix widely used in traditional Chinese medicine for numerous diseases including hypertension. The present study aimed to investigate the effect of harpagide on Ang II-induced neuroinflammation and the potential mechanism. Pretreated with harpagide or resatorvid (the TLR4 pathway inhibitor), BV2 cells were treated with Ang II or LPS (the TLR4 activator). NO, pro-inflammatory cytokines, the proteins on TLR4/MyD88/NF-κB signaling pathway and the expression of CD86, CD206, TREM2 in BV2 cells were detected respectively. Subsequently, the effects of harpagide on neurotoxicity and BBB destruction triggered by Ang II-induced neuroinflammation were investigated in the co-cultures of BV2 microglia/HT22 hippocampal neurons, BV2 microglia/bEnd.3 endotheliocyte and BV2 microglia/BBB monolayer model. We found that Ang II converted microglia into M1 state and resulted in neuroinflammation through activating TLR4/MyD88/NF-κB signaling pathway. It also triggered the imbalance of TLR4/TREM2 in microglia. Ang II-mediated inflammation microglia further led to neuronal apoptosis and BBB damage. Harpagide showed the effect of alleviating Ang II-mediated neuroinflammation as well as the resulting neurotoxicity and BBB destruction through inhibiting the TLR4/MyD88/NF-κB pathway. The anti-inflammatory and neuroprotective effect of harpagide suggested that it might be a potential therapeutic strategy in hypertensive cSVD.

Gandouling Tablets Inhibit Excessive Mitophagy in Toxic Milk (TX) Model Mouse of Wilson Disease via Pink1/Parkin Pathway.

OBJECTIVE: Gandouling (GDL) tablet is a Chinese patent medicine approved by the National Medical Product Administration, which is used to treat Wilson disease (WD) in China. In this study, we aimed to investigate the effects of GDL on mitophagy in the hippocampus in the toxic milk (TX) mouse model of WD. METHODS: Mice were randomly divided into the following four groups: control, Wilson (model group), D-penicillamine (DPA), and GDL groups. The animal behaviors were evaluated by the water maze experiment, traction test, and pole test. Transmission electron microscopy was used for the detection of mitochondrion structure. An enzyme-linked immunosorbent assay (ELISA) was performed for the analysis of the changes in liver function. Colocalization of mitophagy-related proteins was detected by fluorescence microscopy. Western blotting (WB) and reverse transcription-polymerase chain reaction (RT-PCR) were conducted for the detection of protein expression and mRNA levels, respectively. RESULTS: Significant reduction in neurological impairments was observed in the WD model group. All of these results were significantly reversed by GDL intervention. Compared with the levels in the Wilson group, the levels of alanine aminotransferase (ALT), aspartate transaminase (AST), total bilirubin (TBIL), and albumin (ALB) changed obviously. Colocalization between mitophagy-related proteins pink1, parkin, and mitochondria was changed significantly. The mitophagy-related mRNA (pink1, parkin, and LC3II) and protein expression levels (pink1, parkin, and the rate of LC3II/LC3I) were decreased significantly, while p62 was remarkably increased after GDL intervention. CONCLUSION: Our findings indicated that the neuroprotective mechanism of GDL may occur via the inhibition of excessive mitophagy through the regulation of the pink1/parkin pathway in the TX mouse brain of WD.

Catalpol provides a protective effect on fibrillary Aß1-42 -induced barrier disruption in an in vitro model of the blood-brain barrier.

Excessive amyloid beta (Aß) deposition in brain is mainly responsible for cell damage and blood-brain barrier (BBB) disruption in Alzheimer's disease (AD). Catalpol, an iridoid glucoside extracted from the root of Rehmannia glutinosa Libosch, has neuroprotective effect against AD. It is unclear whether catalpol has a protective effect on Aß-induced BBB leakage. We employed an immortalized endothelial cell line (bEnd.3) and astrocytes co-culture to mimic a BBB model in vitro and investigated the effect of catalpol on BBB. We found that treatment with catalpol decreased BBB hyperpermeability induced by fibrillar Aß1-42 . Data from western blotting showed that catalpol prevented fibrillar Aß1-42 -induced bEnd.3 cell apoptosis through mitochondria-dependent and death receptor pathways; decreased the levels of matrix metalloproteinases (MMPs), MMP-2, MMP-9, and the receptor for advanced glycation end products; and increased the levels of tight junction proteins (ZO-1, occludin, and claudin-5), low-density lipoprotein receptor-related protein 1, and P-glycoprotein in fibrillar Aß1-42 -treated bEnd.3 cells. Moreover, catalpol also enhanced soluble Aß efflux across the fibrillar Aß1-42 -treated bEnd.3 cells BBB monolayer model. Altogether, our results suggest that catalpol alleviate fibrillar Aß1-42 -induced BBB disruption, enhance soluble Aß clearance, and offer a feasible therapeutic application in AD treatment.