Gegen Qinlian tablets delay Alzheimer's disease progression via inhibiting glial neuroinflammation and remodeling gut microbiota homeostasis.

BACKGROUND: Current therapeutic agents for AD have limited efficacy and often induce undesirable side effects. Gegen Qinlian tablets (GGQLT) are a well-known clearingheat formula used in clinical treatment of inflammatory diseases. Based on traditional Chinese medicine (TCM) theory, the strategy of clearing-heat is then compatible with the treatment of AD. However, it remains unknown whether GGQLT can exert neuroprotective effects and alleviate neuroinflammation in AD. PURPOSE: This study aimed to evaluate the anti-AD effects of GGQLT and to decipher its intricate mechanism using integrative analyses of network pharmacology, transcriptomic RNA sequencing, and gut microbiota. METHODS: The ingredients of GGQLT were analyzed using HPLC-ESI-Q/TOF-MS. The AD model was established by bilateral injection of Aß1-42 into the intracerebroventricular space of rats. The Morris water maze was used to evaluate the cognitive function of the AD rats. The long-term toxicity of GGQLT in rats was assessed by monitoring their body weights and pathological alterations in the liver and kidney. Reactive astrocytes and microglia were assessed by immunohistochemistry by labeling GFAP and Iba-1. The levels of inflammatory cytokines in the hippocampus were evaluated using ELISA kits, RT-PCR, and Western blot, respectively. The potential anti-AD mechanism was predicted by analyses of RNA-sequencing and network pharmacology. Western blot and immunohistochemistry were utilized to detect the phosphorylation levels of IκBα, NF-κB p65, p38, ERK and JNK. The richness and composition of gut bacterial and fungal microflora were investigated via 16S rRNA and ITS sequencing. RESULTS: Typical ingredients of GGQLT were identified using HPLC-ESI-Q/TOF-MS. GGQLT significantly improved the cognitive function of AD rats by suppressing the activation of microglia and astrocytes, improving glial morphology, and reducing the neuroinflammatory reactions in the hippocampus. RNA-sequencing, network and experimental pharmacological studies demonstrated that GGQLT inhibited the activation of NF-κB/MAPK signaling pathways in the hippocampus. GGQLT could also restore abnormal gut bacterial and fungal homeostasis and no longer-term toxicity of GGQLT was observed. CONCLUSIONS: Our findings, for the first time, demonstrate GGQLT exhibit anti-AD effects and is worthy of further exploration and development.

Dietary vitamin A modifies the gut microbiota and intestinal tissue transcriptome, impacting intestinal permeability and the release of inflammatory factors, thereby influencing Aß pathology.

Background: Alzheimer's disease (AD) is an age-related neurodegenerative disorder with no effective interventions for curing or modifying its progression. However, emerging research suggests that vitamin A in the diet may play a role in both the prevention and treatment of AD, although the exact mechanisms are not fully understood. Objectives: This study aims to investigate the dietary vitamin A modifies the gut microbiota and intestinal tissue transcriptome, impacting intestinal permeability and the release of inflammatory factors, thereby influencing Aß pathology shedding light on its potential as a dietary intervention for AD prevention and treatment. Methods: The APP/PS1-AD mouse model was employed and divided into three dietary groups: vitamin A-deficient (VAD), normal vitamin A (VAN), and vitamin A-supplemented (VAS) for a 12-week study. Neurobehavioral functions were assessed using the Morris Water Maze Test (MWM). Enzyme-linked immunosorbent assay (ELISA) was used to quantify levels of Diamine Oxidase (DAO), D-lactate, IL-6, IL-1ß, and TNF-a cytokines. Serum vitamin A levels were analyzed via LC-MS/MS analysis. Immunohistochemical analysis and morphometry were performed to evaluate the deposition of Aß in brain tissue. The gut microbiota of APP/PS1 mice was analyzed using 16S rRNA sequencing analysis. Additionally, transcriptomic analysis was conducted on intestinal tissue from APP/PS1 mice. Results: No significant changes in food intake and body weight were observed among the groups. However, the VAD and VAS groups showed reduced food intake compared to the VAN group at various time points. In terms of cognitive function, the VAN group performed better in the Morris Water Maze Test, indicating superior learning and memory abilities. The VAD and VAS groups exhibited impaired performance, with the VAS group performing relatively better than the VAD group. Serum vitamin A concentrations differed significantly among the groups, with the VAS group having the highest concentration. Aß levels were significantly higher in the VAD group compared to both the VAN and VAS groups. Microbial analysis revealed that the VAS and VAN groups had higher microbial diversity than the VAD group, with specific taxa characterizing each group. The VAN group was characterized by taxa such as Actinohacteriota and Desulfovibrionaceae, while the VAD group was characterized by Parabacteroides and Tannerellaceae. The VAS group showed similarities with both VAN and VAD groups, with taxa like Desulfobacterota and Desulfovibrionaceae being present. The VAD vs. VAS, VAD vs. VAN, and VAS vs. VAN comparisons identified 571, 313, and 243 differentially expressed genes, respectively, which associated with cellular and metabolic processes, and pathway analysis revealed enrichment in pathways related to chemical carcinogenesis, drug metabolism, glutathione metabolism, and immune-related processes. The VAD group exhibited higher levels of D-lactate, diamine oxidase, and inflammatory cytokines (TNF-a, IL-1ß, IL-6) compared to the VAN and VAS groups. Conclusion: Dietary vitamin A supplementation modulates the gut microbiota, intestinal permeability, inflammatory factors, and Aß protein formation, offering insights into the pathogenesis of AD and potential therapeutic avenues for further exploration. This research highlights the intricate interplay between diet, gut microbiota, and neurodegenerative processes, emphasizing the importance of dietary interventions in managing AD-related pathologies.

Xiaoyaosan ameliorates depressive-like behavior and susceptibility to glucose intolerance in rat: involvement of LepR-STAT3/PI3K pathway in hypothalamic arcuate nucleus.

BACKGROUND: Accumulating evidence has demonstrated that arcuate nucleus (ARC) of the hypothalamus is likely responsible for the close association between chronic stress, depression, and diabetes. Xiaoyaosan (XYS), a Chinese herbal formula, remarkably improves depressive-like behavior and glucose intolerance, but the mechanism remains unclear. Leptin receptor (LepR) regulates energy expenditure and depression by mediating the action of leptin on the ARC. Therefore, we hypothesized that XYS may regulate depressive-like behavior and glucose intolerance via the leptin and its cascade LepR-STAT3/PI3K pathway in the ARC. METHODS: A rat model of depressive-like behavior and susceptibility to glucose intolerance was induced by exposure to chronic unpredictable mild stress (CUMS) for six weeks. XYS (2.224 g/kg) was orally gavaged for six weeks, and fluoxetine (2.0 mg/kg) was administrated to the positive control group. Depressive-like behaviors were assessed using the open field test (OFT), sucrose preference test (SPT) and forced swim test (FST). Fasting blood glucose (FBG) and oral glucose tolerance test (OGTT) were performed to evaluate the effects of XYS on blood glucose. Peripheral leptin and blood lipids were detected using enzyme-linked immunosorbent assay and an automatic biochemical analyzer, respectively. The effects of XYS on the LepR-STAT3/PI3K pathway were detected by quantitative real-time PCR and western blotting. RESULTS: XYS ameliorated CUMS-induced depressive-like behaviors and elevated blood glucose. XYS improved the food intake but have no significant effects on the body weight. Peripheral leptin and its central receptor were also suppressed by XYS, accompanied by the downregulation of JAK2/STAT3 and PI3K/AKT pathway in the ARC. Additionally, XYS increased AGRP and NPY expression but inhibited POMC in the ARC. CONCLUSIONS: XYS improves depressive-like behaviors and susceptibility to glucose intolerance induced by CUMS, which may be achieved by the downregulation of the LepR-STAT3/PI3K signaling pathway in the ARC.

Antidepressant Mechanism of Traditional Chinese Medicine Formula Xiaoyaosan in CUMS-Induced Depressed Mouse Model via RIPK1-RIPK3-MLKL Mediated Necroptosis Based on Network Pharmacology Analysis.

Background: Depression is a stress-related disorder that seriously threatens people's physical and mental health. Xiaoyaosan is a classical traditional Chinese medicine formula, which has been used to treat mental depression since ancient times. More and more notice has been given to the relationship between the occurrence of necroptosis and the pathogenesis of mental disorders. Objective: The purpose of present study is to explore the potential mechanism of Xiaoyaosan for the treatment of depression using network pharmacology and experimental research, and identify the potential targets of necroptosis underlying the antidepressant mechanism of Xiaoyaosan. Methods: The mice model of depression was induced by chronic unpredictable mild stress (CUMS) for 6 weeks. Adult C57BL/6 mice were randomly divided into five groups, including control group, chronic unpredictable mild stress group, Xiaoyaosan treatment group, necrostatin-1 (Nec-1) group and solvent group. Drug intervention performed from 4th to 6th week of modeling. The mice in Xiaoyaosan treatment group received Xiaoyaosan by intragastric administration (0.254 g/kg/d), and mice in CUMS group received 0.5 ml physiological saline. Meanwhile, the mice in Nec-1 group were injected intraperitoneally (i.p.) with Nec-1 (10 mg/kg/d), and the equivalent volume of DMSO/PBS (8.3%) was injected into solvent group mice. The behavior tests such as sucrose preference test, forced swimming test and novelty-suppressed feeding test were measured to evaluate depressive-like behaviors of model mice. Then, the active ingredients in Xiaoyaosan and the related targets of depression and necroptosis were compiled through appropriate databases, while the "botanical drugs-active ingredients-target genes" network was constructed by network pharmacology analysis. The expressions of RIPK1, RIPK3, MLKL, p-MLKL were detected as critical target genes of necroptosis and the potential therapeutic target compounds of Xiaoyaosan. Furthermore, the levels of neuroinflammation and microglial activation of hippocampus were measured by detecting the expressions of IL-1ß, Lipocalin-2 and IBA1, and the hematoxylin and eosin (H&E) stained was used to observe the morphology in hippocampus sections. Results: After 6-weeks of modeling, the behavioral data showed that mice in CUMS group and solvent group had obvious depressive-like behaviors, and the medication of Xiaoyaosan or Nec-1 could improve these behavioral changes. A total of 96 active ingredients in Xiaoyaosan which could regulate the 23 key target genes were selected from databases. Xiaoyaosan could alleviate the core target genes in necroptosis and improve the hippocampal function and neuroinflammation in depressed mice. Conclusion: The activation of necroptosis existed in the hippocampus of CUMS-induced mice, which was closely related to the pathogenesis of depression. The antidepressant mechanism of Xiaoyaosan included the regulation of multiple targets in necroptosis. It also suggested that necroptosis could be a new potential target for the treatment of depression.

A network-based analysis and experimental validation of traditional Chinese medicine Yuanhu Zhitong Formula in treating neuropathic pain.

ETHNOPHARMACOLOGICAL RELEVANCE: The Yuanhu Zhitong Formula (YZF) consists of traditional Chinese herbs Corydalis Rhizoma (Corydalis yanhusuo (Y.H.Chou & Chun C.Hsu) W.T.Wang ex Z.Y.Su & C.Y.Wu; Chinese name, Yanhusuo) and Angelicae Dahuricae Radix (Angelica dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav.; Chinese name, Baizhi), which is usually administrated for painful conditions. It is well acknowledged that YZF has pharmacological effects on pain relief; nevertheless, limited data are available on its mechanism. AIM OF THE STUDY: This study aimed to explore the potential mechanism underlying YZF on nociception of rats. Also, the comprehensive mechanism of YZF was preliminarily determined based on network pharmacology on neuropathic pain. MATERIALS AND METHODS: A spared nerve injury (SNI) model was established to reveal the effects of YZF administration on nociceptive behavior in rats. Von-Frey tests were used to evaluate the paw withdrawal mechanical thresholds in rats administrated with YZF or vehicle. The "drug-ingredients" and "disease-drug-target" networks were established with a network pharmacology approach. The analyses of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) profiles were performed based on the common targets between the herbs and neuropathic pain. Hub genes, identified with CytoHubba, were validated by Western blotting analysis. RESULTS: SNI rats developed significant nociceptive behavior as soon as 3 days after nerve injury, which was reversed by consecutive treatment with 300 mg/kg YZF for 7 days. Besides, 50 potential bioactive components in YZF with 1074 targets were identified. Then, 217 putative common genes related to YZF and neuropathic pain were identified for further study. After established a protein-protein interaction network, 12 subnetworks with CytoHubba and 10 predictive hub genes were obtained based on the maximal clique centrality model. Western blotting analysis indicated that SNI rats exhibited increased APP (Amyloid-beta precursor protein), SRC (Proto-oncogene tyrosine-protein kinase Src), and phosphorylation of JNK1 (Mitogen-activated protein kinase 8, JNK) and ERK1/2 (Mitogen-activated protein kinase 3/1). Obviously, continuous administration of YZF robustly reversed such changes. CONCLUSIONS: This study revealed that YZF modulates the nociceptive behavior in SNI rats. Moreover, the drug may be useful in the treatment of neuropathic pain through multi-components, multi-targets, and multi-pathways. Nevertheless, more attention should be paid to discriminating the potential ingredients in YZF contributing to its analgesic effects in the treatment of neuropathic pain.