ABSTRACT The limited efficacy and slow onset of current antidepressants underscore the urgent need for novel therapeutic strategies. Here, we established a novel zebrafish inflammation‐based screening model and identified 18β‐glycyrrhetinic acid (18β‐GA) as a potent anti‐inflammatory candidate. In a chronic social defeat stress (CSDS) mouse model, 18β‐GA demonstrated significant antidepressant effects, which were associated with attenuated neuroinflammation and a shift in microglial polarization toward an anti‐inflammatory phenotype. Mechanistically, 18β‐GA inhibited the mTOR/p70S6K signaling pathway, leading to the restoration of autophagy and subsequent suppression of NLRP3 inflammasome activation in microglia. Using a transwell co‐culture system, we further confirmed that 18β‐GA protects neurons from microglia‐mediated inflammatory injury. To overcome pharmacokinetic limitations, we developed a nanoliposomal formulation (Nano 18β‐GA) that achieved rapid brain accumulation within 0.5 h, as visualized by time‐dependent in vivo imaging. Remarkably, a single administration of Nano 18β‐GA produced significant antidepressant effects, maintained the original mechanism of action, and exhibited a favorable biosafety profile. Together, our work delineates a translational pipeline from natural product discovery to nano‐enabled therapy, offering a rapidly acting strategy with substantial translational potential for depressive disorder.

Xiaoyaosan (XYS) is a classical traditional prescription with well-documented antidepressant effects. However, the active components and molecular mechanisms to alleviate depression remain unclear. In this study, using chronic social defeat stress (CSDS) and lipopolysaccharide (LPS)-induced depression models, we found that XYS and its key ingredient isoliquiritigenin (ILG) not only significantly improved depressive-like behaviors in mice but also exerted dual regulatory effects at the cellular level, promoting hippocampal neural stem cell proliferation and differentiation, while inhibiting microglia-mediated neuroinflammation. Using Hi-C technology, we discovered that XYS and ILG reversed the abnormal chromatin 3D structure in hippocampal microglia of depression models. Integrated analyses of transcriptomics, molecular docking, and 3D genomics identified the transcription factor p65 as a target of XYS and ILG. Co-culture experiments with microglia and neural stem cells further confirmed that overexpression of p65 promotes inflammation and inhibits neuronal growth. In depressed mice, NF-κB p65 expression was elevated and further formed phase separated condensates, which was effectively suppressed by XYS and ILG. This study reveals how XYS and its active component ILG function mechanistically to exert therapeutic effects on depression, including restoring chromatin 3D structure, and normalizing pathological phase separation of NF-κB p65, and reversing depressive phenotypes. Collectively, these findings provide a solid experimental foundation for the development of natural antidepressants.

Introduction: Microglial activation is a key contributor to neuroinflammation in the pathogenesis of major depressive disorder (MDD). Isoliquiritigenin (ILG), a compound derived from medicinal plants such as Glycyrrhiza glabra, has been widely reported to inhibit microglial activation and reduce neuroinflammation; however, its antidepressant effects and underlying mechanisms remain unclear. Objectives: Here, we show that ILG exerts antidepressant effects that are dependent on its suppression of hippocampal microglia. Methods: This study first evaluated the antidepressant efficacy of ILG using multiple established depression models. We then employed pathological, molecular biological, and targeted inhibition approaches to establish the necessity of microglial involvement in ILG's antidepressant action. Furthermore, single-cell RNA sequencing was utilized to characterize the microglial landscape in depression and to identify the key microglial subset associated with ILG's therapeutic effect. Finally, we elucidated the regulatory mechanism of ILG on this specific microglial subset through molecular docking, microscale thermophoresis, and site-directed mutagenesis. Results: Specifically, single‑cell RNA sequencing revealed that ILG inhibits a subset of highly phagocytic microglia (HP‑MG), a population characterized by high expression of phagocytosis‑associated genes and markedly activated during depression. Mechanistically, ILG binds to the Thr446 phosphorylation site of PKR, blocking its activation and the downstream NF‑κB/ATF4 signaling cascade, thereby downregulating transcription of the HP‑MG marker gene Saa3 and ultimately suppressing HP‑MG. Conclusion: Taken together, these findings indicate that ILG possesses considerable antidepressant potential, which may be attributable to its inhibition of PKR‑mediated highly phagocytic microglia.

Ethnopharmacological relevance Xiaoyaosan, a classic Chinese herbal formula, exhibits promising antidepressant effects. However, its specific antidepressant mechanisms remain incompletely understood. Previous studies have highlighted the significant role of DNA methylation in the pathogenesis of major depressive disorder (MDD). Yet, whether the effects of Xiaoyaosan are linked to DNA methylation and its regulation remains unclear. Aim of the study This study aims to explore and verify the molecular mechanism of Xiaoyaosan in treating MDD via integrated analysis of DNA methylation and RNA sequencing. Materials and methods In this study, a chronic unpredictable mild stress (CUMS) model was established to induce MDD in rats, which were subsequently orally treated with Xiaoyaosan, with fluoxetine as a positive control. Antidepressant effects were assessed by the open field test, sucrose preference test, and forced swimming test. Whole-genome bisulfite sequencing (WGBS) and bulk RNA sequencing were performed in the arcuate nucleus of hypothalamus to assess methylation changes and identify differentially expressed genes. Bioinformatics analyses were conducted to explore methylation alterations, RNA sequencing profiles, and their shared epigenetic as well as gene expression changes, to identify candidate genes. Finally, RT-PCR was used to validate the key differential genes. Results Xiaoyaosan effectively reversed depressive-like behaviors. Further, Xiaoyaosan treatment involved multiple epigenetic modifications. The results of differentially methylated genes showed that there were 1,353 overlapped genes between M-vs-C-hypo gene and X-vs-M-hyper gene, 5,326 overlapped genes between M-vs-C-hyper gene and X-vs-M-hypo gene. GO and KEGG enrichment analyses indicated these intersecting genes were involved in biological regulation, transcription factors, appetite and endocrine control systems, etc. The analysis of differentially expressed genes from RNA sequencing revealed that there were 25 overlapping genes between the M vs C hypomethylated group and the X vs M hypermethylated group, while 81 overlapping genes were identified between the M vs C hypermethylated group and the X vs M hypomethylated group. Those differential genes regulated by methylation enriched in processes related to brain and neuronal growth, neuropeptide and hormone activation, as well as biological processes and molecular functions associated with protein translation, synthesis, transport, and localization. The integrated analysis of DNA methylation and RNA sequencing screened 14 potentially differential genes, which were associated with appetite regulation, energy metabolism, and neuroreceptor ligands. PCR verification found that Lmx1b, Abcc5, Gpc3 and Cfb showed statistical differences. Conclusions The antidepressant mechanism of Xiaoyaosan involves the biological regulation in the arcuate nucleus of hypothalamus, including transcription factors, neurotransmitter regulation, neural development, appetite regulation peptides, and endocrine control systems. The methylation level and regulation at the gene locus of Lmx1b, Abcc5, Gpc3, and Cfb may play a key role in the treatment of Xiaoyaosan. These findings provide new insights into the therapeutic mechanisms of Xiaoyaosan.

BackgroundXiaoyao pills (XYP) is a commercial Chinese patent medicine used in the treatment of depression. However, the mechanisms underlying its therapeutic effects, as well as the patients who can benefit from XYP, have not been evaluated so far.ObjectivesTo this end, we conducted a double-blinded, random, and placebo-controlled clinical trial of orally administered XYP in patients with depression.MethodsThe 17-item Hamilton Depression Rating Scale (HAMD-17) scores were recorded at baseline, and every 2 weeks after the start of treatment. To further elucidate the epigenetic mechanism of XYP, we performed mRNA sequencing and genome-wide DNA methylation sequencing using peripheral blood leukocytes of patients and healthy.ResultsXYP effectively alleviated the symptoms in patients with mild or moderate depressive disorders, particularly that of psychomotor retardation. XYP restored aberrant gene expression and DNA methylation patterns associated with depression, and the normalization of DNA methylation correlated with downregulation of several genes. In addition, altered DNA methylation levels in the XYP-treated samples were attributed to increased expression of the DNA methyltransferase DNMT1.ConclusionsOur study provides new insights into the epigenetic mechanism underlying depression and the therapeutic effects of XYP, along with an experimental basis for using XYP in the treatment of depression.Trial Registration InformationThe name of the registry and number: U.S. Clinical Trials Registry. The link to the registration: ClinicalTrials.gov ISRCTN12746343 (https://www.isrctn.com/ISRCTN12746343). The name of the trial register is “Efficacy and safety of the Xiaoyao pill for improving the clinical symptoms of stagnation of liver qi (chi) and spleen deficiency”. The clinical trial registration number is ISRCTN12746343.

Ethnopharmacological relevance: In traditional Chinese medicine, Qi-zhi-wei-tong granule (QZWT) significantly reduced the major gastrointestinal and psychological symptoms of functional dyspepsia. Aim of the study: We aimed to explore the therapeutic effect of QZWT treated chronic non-atrophic gastritis (CNAG) and to elucidate its potential mechanism. Materials and methods: The composition of QZWT was analysed by UPLC-Q/TOF-MS. The CNAG mice model was established by chronic restraint stress (CRS) in combination with iodoacetamide (IAA). Morphological staining was utilized to reveal the impact of QZWT on stomach and gut integrity. RT-qPCR and ELISA were used to measure proinflammatory cytokines in the stomach, colon tissues and serum of CNAG mice. Next-generation sequencing of 16 S rDNA was applied to analyse the gut microbiota community of faecal samples. Finally, we investigated the faecal bile acid composition using GC-MS. Results: Twenty-one of the compounds from QZWT were successfully identified by UPLC-Q/TOF-MS analysis. QZWT enhanced gastric and intestinal integrity and suppressed inflammatory responses in CNAG mice. Moreover, QZWT treatment reshaped the gut microbiota structure by increasing the levels of the Akkermansia genus and decreasing the populations of the Desulfovibrio genus in CNAG mice. The alteration of gut microbiota was associated with gut bacteria BA metabolism. In addition, QZWT reduced BAs and especially decreased conjugated BAs in CNAG mice. Spearman's correlation analysis further confirmed the links between the changes in the gut microbiota and CNAG indices. Conclusions: QZWT can effectively inhibited gastrointestinal inflammatory responses of CNAG symptoms in mice; these effects may be closely related to restoring the balance of the gut microbiota and regulating BA metabolism to protect the gastric mucosa. This study provides a scientific reference for the pathogenesis of CNAG and the mechanism of QZWT treatment.

BACKGROUND:Xiaoyaosan (XYS), a traditional Chinese medicine formulation, has been used in the treatment of depression. However, no studies have yet identified the active compounds responsible for its antidepressant effects in the brain. STUDY DESIGN:We investigated the antidepressants effects of XYS and identified 18β-glycyrrhetinic acid (18β-GA) as the primary compound present in the brain following XYS injection. Furthermore, we explored the molecular mechanisms underlying the antidepressant-like effects of both XYS and 18β-GA. METHODS:To investigate the antidepressant-like effects of XYS and elucidate the associated molecular mechanisms, we employed various methodologies, including cell cultures, the chronic social defeat stress (CSDS) model, behavioral tests, immunoprecipitation, quantitative PCR (qPCR) assays, Western blotting assays, luciferase assays, chromatin immunoprecipitation (ChIP) assays, immunofluorescence staining, and dendritic spine analysis. RESULTS:We identified 18β-GA as the primary compound in the brain following XYS injection. In vitro, 18β-GA was found to bind with ERK (extracellular signal-regulated kinase), subsequently activating ERK kinase activity toward both c-Jun and cAMP response element binding protein (CREB). Moreover, 18β-GA activated brain-derived neurotrophic factor (BDNF) transcription by stimulating nuclear factor-erythroid factor 2-related factor 2 (Nrf2), c-Jun, and CREB, while also inhibiting methyl CpG binding protein 2 (MeCP2) both in vitro and in vivo. Chronic intraperitoneal (i.p.) administration of 18β-GA exhibited prophylactic antidepressant-like effects in a CSDS model, primarily by activating BDNF transcription in the medial prefrontal cortex (mPFC). Interestingly, a single i.p. injection of 18β-GA produced rapid and sustained antidepressant-like effects in CSDS-susceptible mice by engaging the BDNF-tropomyosin receptor kinase B (TrkB) signaling pathway in the mPFC. CONCLUSION:These findings suggest that the activation of BDNF transcription in the mPFC underlies the antidepressant-like effects of 18β-GA, a key component of XYS in the brain.

Adult hippocampal neurogenesis generates functional neurons from neural progenitor cells in the hippocampal dentate gyrus (DG) to complement and repair neurons and neural circuits, thus benefiting the treatment of depression. Increasing evidence has shown that aberrant microglial activity can disrupt the appropriate formation and development of functional properties of neurogenesis, which will play a crucial role in the occurrence and development of depression. However, the mechanisms of the crosstalk between microglia and adult hippocampal neurogenesis in depression are not yet fully understood. Therefore, in this review, we first introduce recent discoveries regarding the roles of microglia and adult hippocampal neurogenesis in the etiology of depression. Then, we systematically discuss the possible mechanisms of how microglia regulate adult hippocampal neurogenesis in depression according to recent studies, which involve toll-like receptors, microglial polarization, fractalkine-C-X3-C motif chemokine receptor 1, hypothalamic-pituitary-adrenal axis, cytokines, brain-derived neurotrophic factor, and the microbiota-gut-brain axis, etc. In addition, we summarize the promising drugs that could improve the adult hippocampal neurogenesis by regulating the microglia. These findings will help us understand the complicated pathological mechanisms of depression and shed light on the development of new treatment strategies for this disease.

目的 探讨黄芩汤对溃疡性湿热证小鼠肠道菌群的影响.方法 将C57BL/6雄性小鼠随机分为空白对照(NC)组、模型(DSS)组、黄芩汤(HQD)组,每组7只.除NC组正常饲养外,其余2组均给予高脂高糖饮食,同时暴露在温度32℃、湿度90％环境中,每天持续16 h,连续15 d后,自由饮用2.5％葡聚糖硫酸钠水7 d.HQD组给予黄芩汤(9.1 mg/kg),NC组、DSS组均给予同体积蒸馏水灌胃7 d,期间观察小鼠一般情况,评价其疾病活动指数(disease activity index,DAI).处死小鼠后,取中段结肠评价小鼠病理改变,取盲肠内容物进行16S rDNA高通量测序.结果 与NC组比较,DSS组小鼠DAI评分显著增高,结肠黏膜结构受损,肠道菌群多样性降低,变形菌(Proteobacteria)、拟杆菌属(Bacteroides)、大肠埃希菌-志贺菌属(Escherichia-Shigella)、副拟杆菌属(Parabac-teroides)、瘤胃球菌属(Ruminococcus torques)相对丰度显著提高,厚壁菌门(Firmicutes)、布劳特氏菌属(Blautia)、毛螺菌属(Lach-nospiraceae NK4A136 group)相对丰度显著下降;经黄芩汤治疗后,能显著减轻模型小鼠的疾病活动,修复其结肠的病理损伤,逆转肠道菌群的紊乱.结论 黄芩汤可能通过提高菌群多样性及调节溃疡性结肠炎湿热证小鼠菌群丰度,提升肠黏膜的完整性以发挥生物屏障功能,从而发挥治疗作用.

Simotang oral liquid (SMT) is a traditional Chinese medicine (TCM) consisting of four natural plants and is used to alleviate gastrointestinal side effects after chemotherapy and functional dyspepsia (FD). However, the mechanism by which SMT helps cure these gastrointestinal diseases is still unknown. Here, we discovered that SMT could alleviate gastrointestinal side effects after chemotherapy by altering gut microbiota. C57BL/6J mice were treated with cisplatin (DDP) and SMT, and biological samples were collected. Pathological changes in the small intestine were observed, and the intestinal injury score was assessed. The expression levels of the inflammatory factors IL-1β and IL-6 and the adhesive factors Occludin and ZO-1 in mouse blood or small intestine tissue were also detected. Moreover, the gut microbiota was analyzed by high-throughput sequencing of 16S rRNA amplicons. SMT was found to effectively reduce gastrointestinal mucositis after DDP injection, which lowered inflammation and tightened the intestinal epithelial cells. Gut microbiota analysis showed that the abundance of the anti-inflammatory microbiota was downregulated and that the inflammatory microbiota was upregulated in DDP-treated mice. SMT upregulated anti-inflammatory and anticancer microbiota abundance, while the inflammatory microbiota was downregulated. An antibiotic cocktail (ABX) was also used to delete mice gut microbiota to test the importance of gut microbiota, and we found that SMT could not alleviate gastrointestinal mucositis after DDP injection, showing that gut microbiota might be an important mediator of SMT treatment. Our study provides evidence that SMT might moderate gastrointestinal mucositis after chemotherapy by altering gut microbiota.

BACKGROUND:Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder diagnosed during adolescence and adulthood. Assessment of the long-term risks of the current drugs for ADHD treatment has been insufficient, and little is known concerning the long-term therapeutic effects of psychostimulants. Commercially available traditional Chinese medicine compound oral preparations [e.g., Dimu Ningshen (DMNS)] have been widely used in the clinical treatment of ADHD, but their influence on the interaction between gut microbes and potential metabolomes remains inconclusive.METHODS:We used a series of behavioral experiments to evaluate the behavioral effects of DMNS on adolescent and adult ADHD rats and used 16S rDNA sequencing of gut microbes and nontarget metabolomics to evaluate the potential pathogenesis of ADHD and explore the biological mechanism of DMNS in ADHD treatment.RESULTS:For the first time, DMNS was shown to reduce the excessive activity of adult and adolescent ADHD rats and improve the attention deficit of adult ADHD rats. DMNS improved the structural composition of the ADHD gut microbiota and reduced the abundance of Ruminococcaceae_NK4A214_group, Ruminococcus_2, and Eubacterium_nodatum_group. Simultaneously, DMNS increased the circulating levels of peripheral monoamine neurotransmitter precursors (e.g., phenylalanine) and reduced the circulating levels of peripheral fatty acid amides (e.g., oleamide). Finally, the changes in the ADHD serum metabolites were strongly correlated with the gut microbiota.CONCLUSION:DMNS has a good effect in treating ADHD, and it may exert this effect by regulating the gut microbiota and affecting metabolites in the peripheral circulation.

OBJECTIVE:Depression and metabolic disorders have overlapping psychosocial and pathophysiological causes. Current research is focused on the possible role of adiponectin in regulating common biological mechanisms. Xiaoyao San (XYS), a classic Chinese medicine compound, has been widely used in the treatment of depression and can alleviate metabolic disorders such as lipid or glucose metabolism disorders. However, the ability of XYS to ameliorate depression-like behavior as well as metabolic dysfunction in mice and the underlying mechanisms are unclear. METHODS:An in vivo animal model of depression was established by chronic social defeat stress (CSDS). XYS and fluoxetine were administered by gavage to the drug intervention group. Depression-like behaviors were analyzed by the social interaction test, open field test, forced swim test, and elevated plus maze test. Glucose levels were measured using the oral glucose tolerance test. The involvement of certain molecules was validated by immunofluorescence, histopathology, and Western blotting. In vitro, hypothalamic primary neurons were exposed to high glucose to induce neuronal damage, and the neuroprotective effect of XYS was evaluated by cell counting kit-8 assay. Immunofluorescence and Western blotting were used to evaluate the influences of XYS on adiponectin receptor 1 (AdipoR1), adenosine 5'-monophosphate-activated protein kinase (AMPK), acetyl-coenzyme A carboxylase (ACC) and other related proteins. RESULTS:XYS ameliorated CSDS-induced depression-like behaviors and glucose tolerance impairment in mice and increased the level of serum adiponectin. XYS also restored Nissl bodies in hypothalamic neurons in mice that exhibited depression-like behaviors and decreased the degree of neuronal morphological damage. In vivo and in vitro studies indicated that XYS increased the expression of AdipoR1 in hypothalamic neurons. CONCLUSION:Adiponectin may be a key regulator linking depression and metabolic disorders; regulation of the hypothalamic AdipoR1/AMPK/ACC pathway plays an important role in treatment of depression by XYS.

Context Ulcerative colitis (UC) is a chronic idiopathic inflammatory bowel disease that is closely related to inflammation and apoptosis. The traditional Chinese medicine compound preparation Huangqin decoction (HQD) has been widely used in the clinical treatment of UC, but the specific mechanism of its function is still inconclusive. Objective To explore the pathogenesis of UC based on the IFN-gamma/JAK/ETS signalling pathway, and to clarify the biological mechanism of HQD. Materials and methods Forty 8-week-old male C57BL/6 mice were randomly divided into four groups: normal control, model, model + salazosulfapyridine group (500 mg/kg, p.o., pd) and model + HQD (9.1 g/kg, p.o., pd). Using Dextran sulphate sodium (DSS) salt (2.5%, p.o.)+high-fat diet + hot and humid environment to build a mouse model of UC. One month later, the changes of colon morphology, serum inflammatory factors, intestinal epithelial cell apoptosis and IFN-gamma/JAK/ETS signalling pathway related protein changes in mice were observed. Results Compared with the model group, HQD significantly reduced the pathological score of the model mice's colon (2.60 +/- 0.25 vs. 4.80 +/- 0.37), and reduced the serum IFN-gamma (200.30 +/- 8.45 vs. 413.80 +/- 6.97) and other inflammatory factors, and reduced intestinal epithelial cell apoptosis (24.85 +/- 4.87 vs. 214.90 +/- 39.21). In terms of mechanism, HQD down-regulated IFN-gamma/JAK/ETS signalling pathway related proteins in colon tissue of UC model mice. Conclusions These data indicate that HQD can improve UC by reducing intestinal inflammation and apoptosis, providing experimental evidence for the wide application of HQD in clinical practice of UC.

抑郁症是目前的研究热点之一,众多证据表明抑郁症的发病具有季节性,并于春季高发.肝郁脾虚型抑郁症是抑郁症的主要中医证型,其呈现四季高发、春季突出的流行病学特征.故本文以证候为本,以肝木关系为基、以魂意相生为要,从肝旺于春枢机阴阳、春病延夏脾湿为盛、金木相制收敛肃杀、水不涵木封藏郁闭4个方面,分别论述了肝郁脾虚型抑郁症四时的发病机理.论述了肝郁脾虚型抑郁症季节性发病的病机,主要由3方面因素构成,一是脏腑的阴阳属性和功能特点,二是肝、脾两脏在机体中发挥的基础和调理作用,三是各脏腑之间紧密的生理病理关联.并依据抑郁症的发病特点和季节特性,给予了中医防治建议,即机体应顺应四时规律饮食作息,其次四季均要以顾护脾胃为主.