Exploration of the potential mechanism of Yiyi Tongfeng Formula in the treatment of acute gouty arthritis based on network pharmacology and molecular docking: A review.

The global prevalence of gout is on the rise. Yiyi Tongfeng Formula (YTF), a traditional herbal compound, has gained recognition for its efficacy in managing acute gouty arthritis (AGA). Despite its widespread use, the underlying mechanisms of YTF in AGA treatment remain largely undefined. This study employed network pharmacology and molecular docking to elucidate these mechanisms. We utilized the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, SymMap database, and various literature sources to identify active components and corresponding targets of YTF. Relevant AGA-associated targets were identified through the Genecards, Drugbank, Therapeutic Target Database, and Online Mendelian Inheritance in Man databases. A protein-protein interaction network was constructed to delineate interactions between YTF targets and AGA. Key ingredients and central targets were further analyzed using Cytoscape. Functional enrichment analyses, including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, were conducted via Metascape. Additionally, molecular docking studies were performed using PyMOL and AutoDock4. It was found that quercetin, kaempferol, and luteolin may be the main active components of YTF for AGA treatment. Gene Ontology enrichment analysis shows that the main biological processes involved are cellular responses to lipids, and inflammatory responses. Kyoto Encyclopedia of Genes and Genomes enrichment analysis suggests the involvement of the IL-17 signaling pathway, AGE-RAGE signaling pathway in diabetic complications, TNF signaling pathway, and so on. The findings suggest a multi-faceted therapeutic approach of YTF in treating AGA, involving multiple components, targets, biological processes, and signaling pathways. This comprehensive mechanism offers a foundation for further experimental validation.

[Huangqin Qingrechubi Capsule alleviates inflammation and uric acid and lipid metabolism imbalance in rats with gouty arthritis by inhibiting the PTEN/PI3K/AKT signaling pathway].

OBJECTIVE: To investigate the effects of Huangqin Qingrechubi Capsule (HQC) on inflammation and uric acid and lipid metabolism in rats with gouty arthritis (GA) and its mechanism. METHODS: SD rat models of GA established by injecting monosodium urate into the right ankle joint were treated with saline, colchicine and HQC at low, medium and high doses (n=10) by gavage for 7 days. Toe swelling of the rats was detected at 4, 8, 24, 48 and 72 h after modeling, and synovial histological changes were observed with HE staining. Serum levels of interleukin-10 (IL-10), IL-18, tumor necrosis factor-α (TNF-α), transforming growth factor-ß1 (TGF-ß1), adiponectin, leptin, resistin and visfatin were measured by ELISA, and the levels of high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), total cholesterol (TC), and uric acid (BUA) were detected. RTqPCR and Western blotting were used to detect the mRNA expressions of phosphatase and tensin homolog (PTEN), phosphatidylinositol-3-kinase (PI3K) and protein kinase B (AKT) and the protein expressions of PTEN, PI3K, p-PI3K, AKT and p-AKT. RESULTS: The rat models of GA showed obvious toe swelling, which reached the peak level at 48 h. HE staining revealed massive inflammatory cell infiltration and synovial tissue hyperplasia. The rat models showed significantly increased expressions of TNF-α, TGF-ß1, IL-18, TC, TG, leptin, resistin and visfatin, BUA, p-PI3K, and p-AKT and lowered levels of IL-10, APN, HDL-C, and PTEN. Treatment with HQC and colchicine obviously improved these changes and alleviated synovial pathologies and toe swelling in the rat models. CONCLUSION: HQC can improve inflammation and correct the imbalance of uric acid and lipid metabolism in GA rats possibly by inhibiting the PTEN/PI3K/AKT signaling pathway.

Network pharmacology and molecular docking to explore the treatment potential and molecular mechanism of Si-Miao decoction against gouty arthritis.

Gouty arthritis (GA) is a common metabolic rheumatological disease. Si-Miao decoction has therapeutic effects on GA. In our study, we investigated the mechanism of Si-Miao decoction against GA using network pharmacology and molecular docking analytical methods. The Traditional Chinese Medicine Systems Pharmacology Database was used as the basis for screening the main targets and agents of the Si-Miao decoction, and the Genecards, OMIM, and Drugbank databases were used to screen GA-related targets. They were analyzed using Venn with the drug targets to obtain the intersection targets. We used Cytoscape 3.9.1 to draw the "Drugs-Compounds-Targets" network and the String database for creative protein-protein interaction networks of target genes and filtered core targets. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used to analyze the core targets. Molecular docking was performed using AutoDockTools to predict the binding capacity between nuclear targets and active components in the Si-Miao decoction. A total of 50 chemically active components containing 53 common targets of Si-Miao decoction anti-GA and 53 potential drug target proteins were identified. Core targets, namely, TNF, STAT3, SRC, PPARG, TLR4, PTGS2, MMP9, RELA, TGFB1, and SIRT1, were obtained through PPI network analysis. GO and KEGG analyses showed that the mechanism of anti-GA in Si-Miao decoction may proceed by regulating biological processes such as inflammatory factor levels, cell proliferation, apoptosis, and lipid and glucose metabolism, and modulating the NOD-like receptor signaling pathway, IL-17 signaling pathway, TNF signaling pathway, NF-kappa B signaling pathway, and Toll-like receptor signaling pathway. We further screened the core targets, including PTGS2, MMP9, and PPAGR, as receptor proteins based on their degree value and molecular docking with the main active compounds in Si-Miao decoction, and found that baicalein had high affinity. In conclusion, Si-Miao decoction, through anti-inflammatory, apoptosis-regulating, and anti-oxidative stress action mechanisms in the treatment of GA.

Study on the effects of intestinal flora on gouty arthritis.

Gouty arthritis (GA), a metabolic and immunologic disease, primarily affects joints. Dysbiosis of intestinal flora is an important cause of GA. The metabolic disorders of intestinal flora leading to GA and immune disorders might play an important role in patients with hyperuricemia and established GA. However, the exact mechanisms, through which the dysbiosis of intestinal flora causes the development of GA, are not fully understood yet. Moreover, several therapies commonly used to treat GA might alter the intestinal flora, suggesting that modulation of the intestinal flora might help prevent or treat GA. Therefore, a better understanding of the changes in the intestinal flora of GA patients might facilitate the discovery of new diagnostic and therapeutic approaches. The current review article discusses the effects of intestinal flora dysbiosis on the pathogenesis of GA and the cross-regulatory effects between gut flora and drugs for treating GA. This article also highlights the modulatory effects of gut flora by traditional Chinese medicine (TCM) to lower uric acid levels and relieve joint pain as well as provides a summary and outlook, which might help guide future research efforts.

Identification of O-arylated huperzinines as novel cholinergic anti-inflammatory pathway agonists against gout arthritis.

Lycodine alkaloids are important natural products with diverse biological effects. In this manuscript, we set out the first structural optimization of the 2-pyridone moiety of Lycodine alkaloid via selective O-arylation under metal-free conditions and obtained a series of potent bioactive molecules against monosodium urate (MSU)-induced IL-1ß production. Further investigations demonstrated that these natural product derivatives could activate the neuro-immunomodulatory cholinergic anti-inflammatory pathway (CAP) to block the initial phase of NLRP3 inflammasome activation. Compared with the clinical drugs hydrocortisone and indomethacin, as well as commercially available CAP agonists GTS-21 and pnu282987, 3k and 3q possessed greater potency against MSU-induced IL-1ß production. Meanwhile, these molecules possessed less cytotoxicity against promonocytic THP-1 macrophages when compared with colchicine. This work reports a concise strategy for direct modification of 2-pyridone moiety from natural Lycodine alkaloids, and provides novel frameworks for discovering CAP activators and drugs for gout arthritis.

Mechanism of Reactive Oxygen Species-Guided Immune Responses in Gouty Arthritis and Potential Therapeutic Targets.

Gouty arthritis (GA) is an inflammatory disease caused by monosodium urate (MSU) crystals deposited in the joint tissues causing severe pain. The disease can recur frequently and tends to form tophus in the joints. Current therapeutic drugs for the acute phase of GA have many side effects and limitations, are unable to prevent recurrent GA attacks and tophus formation, and overall efficacy is unsatisfactory. Therefore, we need to advance research on the microscopic mechanism of GA and seek safer and more effective drugs through relevant targets to block the GA disease process. Current research shows that the pathogenesis of GA is closely related to NLRP3 inflammation, oxidative stress, MAPK, NET, autophagy, and Ferroptosis. However, after synthesizing and sorting out the above mechanisms, it is found that the presence of ROS is throughout almost the entire spectrum of micro-mechanisms of the gout disease process, which combines multiple immune responses to form a large network diagram of complex and tight connections involved in the GA disease process. Current studies have shown that inflammation, oxidative stress, cell necrosis, and pathological signs of GA in GA joint tissues can be effectively suppressed by modulating ROS network-related targets. In this article, on the one hand, we investigated the generative mechanism of ROS network generation and its association with GA. On the other hand, we explored the potential of related targets for the treatment of gout and the prevention of tophus formation, which can provide effective reference ideas for the development of highly effective drugs for the treatment of GA.

Triptolide alleviates acute gouty arthritis caused by monosodium urate crystals by modulating macrophage polarization and neutrophil activity.

The present study focused on the efficacy and role of triptolide (TPL) in relieving symptoms of acute gouty arthritis (AGA) in vivo and in vitro. The effects of TPL in AGA were investigated in monosodium urate (MSU)-treated rat ankles, RAW264.7 macrophages, and neutrophils isolated from mouse peritoneal cavity. Observation of pathological changes in the ankle joint of rats. Enzyme-linked immunosorbent assay and real-time quantitative polymerase chain reaction (RT-qPCR) were performed to detect the expression levels of inflammatory factors and chemokines. The levels of the indicators of macrophage M1/M2 polarization, and the mechanistic targets of Akt and rapamycin complex 2, were determined via western blotting and RT-qPCR. The expression levels of CD86 and CD206 were detected using immunohistochemistry. Neutrophil migration was observed via air pouch experiments in vivo and Transwell cell migration assay in vitro. Myeloperoxidase (MPO) and Neutrophil elastase (NE) release was analyzed by via immunohistochemistry and immunofluorescence. The expression levels of beclin-1, LC3B, Bax, Bcl-2, and cleaved caspase-3 in neutrophils were determined via western blotting and immunofluorescence. Neutrophil apoptosis was detected using the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Our results suggest that TPL inhibited inflammatory cell infiltration in rat ankle joints and inflammatory factor and chemokine secretion in rat serum, regulated macrophage polarization through the PI3K/AKT signaling pathway, suppressed inflammatory factor and chemokine expression in neutrophils, and inhibited neutrophil migration, neutrophil extracellular trap formation, transitional autophagy, and apoptosis. This suggests that TPL can prevent and treat MSU-induced AGA by regulating macrophage polarization through the PI3K/Akt pathway and modulating neutrophil activity.

Analysis of the effectiveness and safety of Jiedu Xiezhuo Yishen Tang in the treatment of gouty arthritis: An observational study.

This study is for exploring the effectiveness and security of Jiedu Xiezhuo Yishen Tang in the treatment of gouty arthritis. This retrospective study collected 100 patients with gouty arthritis between February 2022 and February 2023. According to the different treatment methods, the data of patients were divided into control group and experimental group. The control group received routine treatment with benzbromarone, while the experimental group received additional treatment with Xuedu Xiezhuo Yishen Tang on the basis of the control group. The evaluation indicators for the effectiveness of treatment include serum levels of 8-hydroxydeoxyguanosine, 3-NT, interleukin-6, interleukin-10, interleukin-1ß, tumor necrosis factor-α, C-reactive protein, erythrocyte sedimentation rate, urea nitrogen, creatinine, evaluation of knee joint function and pain level, traditional Chinese medicine syndrome score, and safety evaluation. After treatment, the overall treatment effect of the experimental group reached 98%, while the control group was 78%. After treatment, the differences in various indicators possessed statistical significance (SS) (P < .05). In the Lysholm score, the improvement in the experimental group was markedly more excellent than the control group, and the difference possessed SS (P < .05). In the NRS score, the experimental group's NRS score decreased from 8.39 to 1.08 before and after treatment, while the control group only decreased to 3.61. In addition, both groups of patients showed significant improvement in the joint score in the Traditional Chinese medicine syndrome sub-items. The experimental group was able to effectively improve symptoms such as joint pain, joint redness and swelling, joint fever, and limited joint mobility. After treatment, the incidence of adverse reactions in the experimental group was only 8%, while the incidence of adverse reactions in the control group was 24%. After statistical analysis of the incidence of adverse reactions during treatment among the participants, it was found that the difference possessed SS (P < .001). The combination treatment of Jiedu Xiezhuo Yishen Tang and benbromarone can effectively improve oxidative stress response and significantly reduce blood uric acid levels. Meanwhile, this combination therapy can effectively inhibit inflammatory reactions, significantly alleviate knee joint pain, and promote the recovery of knee joint function. This treatment regimen has lower toxic side effects and higher safety.

Study on the Underlying Mechanism of Yinhua Gout Granules in the Treatment of Gouty Arthritis by Integrating Transcriptomics and Network Pharmacology.

Purpose: Yinhua Gout Granules (YGG) is a traditional Chinese medicine preparation with a variety of pharmacological effects, and its clinical efficacy in the treatment of gouty arthritis (GA) has been fully confirmed. However, the pharmacodynamic basis of YGG and its anti-inflammatory mechanism of action in GA are unknown. The objective of this study was to identify the active components and molecular mechanisms of YGG in the treatment of GA. Methods: Ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) and network pharmacology were used to identify and predict the potential active ingredients and related signaling pathways. Then, we revealed the anti-GA effects of YGG based on pharmacodynamic experiments in GA rats. Finally, we integrated transcriptomics and network pharmacology to elucidate the potential mechanism of action and verified the putative mechanism by molecular docking, immunohistochemical (IHC) and Western blot. Results: We have identified 10 major active components of YGG that may have anti-GA effects, such as ferulic acid, rutin, luteolin, etc. Using molecular docking, we found that 10 major compounds could bind well to TNF, PTGS2, IL-6, IL1ß, NOS2 and PTGS1, and the binding energies were all less than -5 kcal/mol. Animal studies have shown that YGG can improve joint inflammation and inflammatory cell infiltration, reduce serum UA, BUN and Cr levels (p<0.01), and decrease IL-1ß, IL-6, TNF-α, COX-2 and PGE2 levels in synovial tissue (p<0.01), which are associated with the pathogenesis of GA. IHC and Western blot results showed that YGG could regulate TLR4/MYD88/NF-κB pathway to inhibit the inflammatory response induced by GA. Conclusion: This study found that YGG could not only improve the disease of GA by inhibiting the production of UA in the body, but also target the regulation of TLR4/MYD88/NF-κB signaling pathway through a variety of active components to achieve effective therapeutic effects on GA.

Targeting Myeloperoxidase Ameliorates Gouty Arthritis: A Virtual Screening Success Story.

This study presents a new approach for identifying myeloperoxidase (MPO) inhibitors with strong in vivo efficacy. By combining inhibitor-like rules and structure-based virtual screening, the pipeline achieved a 70% success rate in discovering diverse, nanomolar-potency reversible inhibitors and hypochlorous acid (HOCl) scavengers. Mechanistic analysis identified RL6 as a genuine MPO inhibitor and RL7 as a potent HOCl scavenger. Both compounds effectively suppressed HOCl production in cells and neutrophils, with RL6 showing a superior inhibition of neutrophil extracellular trap release (NETosis). In a gout arthritis mouse model, intraperitoneal RL6 administration reduced edema, peroxidase activity, and IL-1ß levels. RL6 also exhibited oral bioavailability, significantly reducing paw edema when administered orally. This study highlights the efficacy of integrating diverse screening methods to enhance virtual screening success, validating the anti-inflammatory potential of potent inhibitors, and advancing the MPO inhibitor research.

Investigating the involvement of the NLRP3/ASC/caspase-1 and NF-κb/MAPK pathways in the pathogenesis of gouty arthritis: Insights from irradiated and non-irradiated Trifolium alexandrium L. extracts and some metabolites.

ETHNOPHARMACOLOGICAL RELEVANCE: Trifolium alexandrinum L. (TA), has traditionally been used in folk medicine for its anti-inflammatory properties against hyperuricemia and gout. However, the specific mechanisms of action of TA have not been thoroughly studied. AIM OF THE WORK: This study aimed to evaluate the protective effects of irradiated (TR25) and non-irradiated (TR0) Trifolium alexandrinum L. aqueous extract (TAAE), along with two isolated compounds, caffeine (CAF) and saponin (SAP), in a rat model of acute gouty arthritis (GA). MATERIALS AND METHODS: The GA model was established by injecting a monosodium urate (MSU) suspension into the knee joint. Synovial tissue pathology was assessed, and levels of TNF-α, IL-6, IL-1ß, NF-κB, mTOR, AKT1, PI3K, NLRP3, and ASC were measured by ELISA. mRNA expression of ERK1, JNK, and p-38 MAPK was detected using qRT-PCR, and Caspase-1 protein expression was assessed by immunohistochemical analysis. Knee swelling, uric acid levels, liver and kidney function, and oxidative stress markers were also evaluated. RESULTS: TAAE analysis identified 170 compounds, with 73 successfully identified using LC-HR-MS/MS, including caffeine citrate and theasapogenol B glycoside as the main constituents. The studied materials demonstrated significant protective effects against GA. TR25 administration significantly mitigated knee joint circumference compared to other treatments. It demonstrated potential in alleviating hyperuricemia, renal and hepatic impairments induced by MSU crystals. TR25 also alleviated oxidative stress and reduced levels of IL1ß, IL-6, TNF-α, and NF-κB. Weak Caspase-1 immune-positive staining was observed in the TR25 group. TR25 decreased NLRP3 and ASC expression, reducing inflammatory cytokine levels in GA. It effectively inhibited the PI3K, AKT, and mTOR signaling pathways, promoting autophagy. Additionally, TR25 suppressed ERK1, JNK, and p-38 MAPK gene expression in synovial tissue. These effects were attributed to various components in TAAE, such as flavonoids, phenolic acids, tannins, alkaloids, and triterpenes. CONCLUSION: Importantly, irradiation (25 KGy) enhanced the antioxidant effects and phtchemical contents of TAAE. Additionally, TR0, TR25, CAF, and SAP exhibited promising protective effects against GA, suggesting their therapeutic potential for managing this condition. These effects were likely mediated through modulation of the NLRP3/ASC/Caspase-1 and ERK/JNK/p-38 MAPK signaling pathways, as well as regulation of the PI3K/AKT/mTOR pathway. Further research is warranted to fully elucidate the underlying mechanisms and optimize their clinical applications.

[Modern understanding of uric acid metabolism disorders and progress in traditional Chinese medicine prevention and treatment].

The abnormal production and/or excretion of uric acid can lead to a disorder in uric acid metabolism, resulting in hyperuricemia, uric acid nephropathy, gouty arthritis, and other diseases related to uric acid metabolism disorder. The clinical incidence of these diseases is increasing year after year, posing a significant threat to public health. In the past, hyperuricemia and gouty arthritis were often considered different diseases, with uric acid nephropathy being a complication of hyperuricemia. However, recent research has challenged this perspective, suggesting that hyperuricemia, uric acid nephropathy, and gouty arthritis are different stages of the same disease, with urate deposition as the common pathological feature. This article offered a comprehensive overview of the current understanding of hyperuricemia, uric acid nephropathy, and gouty arthritis in both traditional Chinese medicine(TCM) and western medicine. It delved into the most up-to-date insights into the involvement of urate deposition in the pathogenesis of uric acid metabolism disorders and highlighted the dominant role of TCM in the prevention and treatment of uric acid metabolism disorders, so as to provide a reference for effective intervention strategies and drug development in uric acid metabolism disorder-related diseases.

Euphorbia factor L2 alleviated gouty inflammation by specifically suppressing both the priming and activation of NLRP3 inflammasome.

Euphorbia L. is a traditionally used herb and contains many newly identified compounds with novel chemical structures. Euphorbia factor L2 (EFL2), a diterpenoid derived from Euphorbia seeds, is reported to alleviate acute lung injury and arthritis by exerting anti-inflammatory effects. In this study, we aimed to test the therapeutic benefit and mechanisms of EFL2 in NLRP3 inflammasome-mediated gouty models and identified the potential molecular mechanism. A cell-based system was used to test the specific inhibitory effect of EFL2 on NLRP3-related inflammation. The gouty arthritis model and an air pouch inflammation model induced by monosodium urate monohydrate (MSU) crystals were used for in vivo experiments. Nlrp3-/- mice and in vitro studies were used for mechanistic exploration. Virtual molecular docking and biophysical assays were performed to identify the direct binding and regulatory target of EFL2. The inhibitory effect of EFL2 on inflammatory cell infiltration was determined by flow cytometry in vivo. The mechanism by which EFL2 activates the NLRP3 inflammasome signaling pathway was evaluated by immunological experiment and transmission electron microscopy. In vitro, EFL2 specifically reduced NLRP3 inflammasome-mediated IL-1ß production and alleviated MSU crystal-induced arthritis, as well as inflammatory cell infiltration. EFL2 downregulated NF-κB phosphorylation and NLRP3 inflammasome expression by binding to glucocorticoid receptors. Moreover, EFL2 could specifically suppress the lysosome damage-mediated NLRP3 inflammasome activation process. It is expected that this work may be useful to accelerate the development of anti-inflammatory drugs originated from traditional herbs and improve therapeutics in gout and its complications.

Well-defined alginate oligosaccharides ameliorate joint pain and inflammation in a mouse model of gouty arthritis.

Background: Gouty arthritis causes severe pain and inflammation. Alginate oligosaccharides (AOSs) are natural products derived from alginate and have anti-inflammatory properties. We explored the potential effects of AOSs with different degrees of polymerization (Dp) on gouty arthritis and associated mechanisms. Methods: We established a mouse model of gouty arthritis by injecting monosodium urate (MSU) into ankle joint. Nocifensive behavior, gait and ankle swelling were used to study AOS's effects. Biochemical assays, in vivo imaging, live cell Ca2+ imaging, electrophysiology, RNA-sequencing, etc. were used for mechanism exploration. Results: AOS2 (Dp=2), AOS3 (Dp=3) and AOS4 (Dp=4) all inhibited ankle swelling, whereas AOS2&3 produced the most obvious analgesia on model mice. AOS3, which was picked for further evaluation, produced dose-dependent ameliorative effects on model mice. AOS3 reversed gait impairments but did not alter locomotor activity. AOS3 inhibited NLRP3 inflammasome activation and inflammatory cytokine up-regulation in ankle joint. AOS3 ameliorated MSU-induced oxidative stress and reactive oxygen species (ROS) production both in vivo and in vitro and reversed the impaired mitochondrial bioenergetics. AOS3 activated the Nrf2 pathway and promoted Nrf2 disassociation from Keap1-bound complex and Nrf2 nuclear translocation, thus facilitating antioxidant gene expression via Nrf2-dependent mechanism. Nrf2 gene deficiency abolished AOS3's ameliorative effects on pain, inflammation and oxidative stress in ankle joints of model mice. AOS3 reduced TRPV1 functional enhancement in DRG neurons and constrained neuroactive peptide release. Conclusions: AOS3 ameliorates gouty arthritis via activating Nrf2-dependent antioxidant signaling, resulting in suppression of ROS-mediated NLRP3 inflammasome activation and TRPV1 enhancement. AOS3 may be novel therapeutics for gouty arthritis.

Guizhi Shaoyao Zhimu Decoction ameliorates gouty arthritis in rats via altering gut microbiota and improving metabolic profile.

BACKGROUND: The incidence of gouty arthritis (GA) has gradually increased, and modern drug therapies have obvious side effects. Guizhi Shaoyao Zhimu Decoction (GSZD), a classic prescription in Traditional Chinese Medicine for treating various osteoarthritis, has shown significant advantages in curing GA. PURPOSE: To verify the therapeutic effect of GSZD on GA and investigate its potential pharmacological mechanism via integrated analysis of the gut microbiota and serum metabolites for the first time. METHODS: The chemical composition of GSZD was determined using UPLC-MS. The GA rat model was established by the induction of a high-purine diet combined with local injection. We examined the effects and mechanisms of GSZD after 21 d using enzyme-linked immunosorbent assays, 16S rRNA, and non-targeted metabolomics. Finally, correlation analysis and validation experiment were performed to explore the association among the gut microbiota, serum metabolites, and GA-related clinical indices. RESULTS: In total, 19 compounds were identified as GSZD. High-purine feedstuff with local injection-induced arthroceles were significantly attenuated after GSZD treatment. GSZD improved bone erosion and reduced the serum levels of inflammatory factors (lipopolysaccharide, tumor cell necrosis factor-α, and interleukin) and key indicators of GA (uric acid). 16S rRNA analysis indicated that GSZD-treated GA rats exhibited differences in the composition of the gut microbiota. The abundance of flora involved in uric acid transport, including Lactobacillus, Ruminococcaceae, and Turicibacter, was elevated to various degrees, whereas the abundance of bacteria involved in inflammatory responses, such as Blautia, was markedly reduced after treatment. Moreover, serum metabolite profiles revealed 27 different metabolites associated with the amelioration of GA, which primarily included fatty acids, glycerophospholipids, purine metabolism, amino acids, and bile acids, as well as primary metabolic pathways, such as glycerophospholipid metabolism and alanine. Finally, correlation analysis of the heat maps and validation experiment demonstrated a close relationship among inflammatory cytokines, gut microbial phylotypes, and metabolic parameters. CONCLUSION: This study demonstrated that GSZD could modulate the gut microbiota and serum metabolic homeostasis to treat GA. In addition, the application of gut microbiota and serum metabolomics correlation analyses sheds light on the mechanism of Traditional Chinese Medicine compounds in the treatment of bone diseases.

Discovery of N-Substituted Acetamide Derivatives as Promising P2Y14R Antagonists Using Molecular Hybridization Based on Crystallographic Overlay.

P2Y14 receptor (P2Y14R) is activated by uridine 5'-diphosphate-glucose, which is involved in many human inflammatory diseases. Based on the molecular docking analysis of currently reported P2Y14R antagonists and the crystallographic overlap study between the reported P2Y14R antagonist compounds 6 and 9, a series of N-substituted-acetamide derivatives were designed, synthesized, and identified as novel and potent P2Y14R antagonists. The most potent antagonist, compound I-17 (N-(1H-benzo[d]imidazol-6-yl)-2-(4-bromophenoxy)acetamide, IC50 = 0.6 nM) without zwitterionic character, showed strong binding ability to P2Y14R, high selectivity, moderate oral bioactivity, and improved pharmacokinetic profiles. In vitro and in vivo evaluation demonstrated that compound I-17 had satisfactory inhibitory activity on the inflammatory response of monosodium urate (MSU)-induced acute gouty arthritis. I-17 decreased inflammatory factor release and cell pyroptosis through the NOD-like receptor family pyrin domain-containing 3 (NLRP3)/gasdermin D (GSDMD) signaling pathway. Thus, compound I-17, with potent P2Y14R antagonistic activity, in vitro and in vivo efficacy, and favorable bioavailability (F = 75%), could be a promising lead compound for acute gouty arthritis.

Structure-activity relationships of natural and synthetic lathyrane-based diterpenoids for suppression of NLRP3-driven inflammation and gouty arthritis.

Lathyrane-based diterpenoid is one of the critical bioactive elements of Euphorbia lathyris L., a widely used traditional Chinese medicine for the treatment of inflammation and infection. In this study, we introduced and evaluated seven synthetic or natural lathyrane-based diterpenoids with the same core structure but notable structural variations at specific positions, for their anti-inflammatory and gout-alleviating properties. There was no significant cytotoxicity below 10 µM among the initial test of the cell counting kit 8 of the seven candidate derivatives (compounds 13 to 19) in this work. Furthermore, maintaining the acyloxy group at 15-C position and the strongly hydrophobic aryl structure at 3-C and 5-C positions, compounds 15 (Euphorbia factor L3, EFL3) and 17 strikingly inhibited the production of IL-1ß related to the actuation of the inflammasome in our study. The ELISA assay indicated that the anti-inflammatory effects of EFL3 were better associated with MSU stimulation than other second-line pathways triggered by inflammasome. Further examinations on the acute paw gout model in C57BL/6 mice showed that EFL3 had a significantly inflammatory retarding effect by intraperitoneal injection. It decreased swelling volume as well as the cleavage and activation of local IL-1ß and casepas-1 in the paw. To conclude, our findings reveal several potential key structure-activity relationships that govern the anti-inflammatory effects of lathyrane-type diterpenoids, the dispensable acyl group at the 15-C position, the importance of maintaining the spatial structure of the B-ring, and the potential importance of hydrophobic substituents at the 3-C position. These insights may provide guidance for the structural design of lathyrane-type agents in the future; furthermore, we found that the lathyrane-based diterpenoid EFL3 is a potential agent for gout that is expected to provide a novel therapeutic strategy for inflammation intervention.

The alleviatory effects of koumine on MSU-induced gouty arthritis via the TLR4/NF-κB/NLRP3 pathway.

The aim of this study was to validate the preventive effects of koumine (KM), a monoterpene indole alkaloid, on gouty arthritis (GA) and to explore its possible mechanisms. C57BL/6 mice were intraperitoneally administered KM (0.8, 2.4 or 7.2 mg/kg), colchicine (3.0 mg/kg) or sterile saline. One hour later, a monosodium urate (MSU) suspension was injected into the right hind paws of the mice to establish an acute gout model. Inflammation symptoms were evaluated at 0, 3, 6, 12 and 24 h, and the mechanical withdrawal threshold was evaluated at 0, 6 and 24 h. After 24 h, the mice were euthanized, and the joint tissue, kidney and blood were collected for subsequent experiments. Histological examination and antioxidant enzyme, kidney index and serum uric acid (UA) measurements were taken. The expression levels of the signalling pathway components were determined. KM effectively alleviated the symptoms of redness, swelling and pain; counteracted inflammatory cell infiltration; and increased antioxidant enzyme levels, reduced kidney index and serum UA levels through regulating UA excretion in MSU-induced mice. The expression of toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB)/nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 (NLRP3) signalling pathway proteins and mRNA were reduced in the KM group. These results suggest that KM may be effective in alleviating GA through the TLR4/NF-κB/NLRP3 pathway.

Honokiol alleviates monosodium urate-induced gouty pain by inhibiting voltage-gated proton channels in mice.

OBJECTIVE: To investigate whether honokiol (HNK) acted as an analgesic in connection with inhibiting the voltage-gated proton channel (Hv1). METHODS: The model of gouty arthritis was induced by injecting monosodium urate (MSU) crystals into the hind ankle joint of mice. HNK was given by intragastric administration. Ankle swelling degree and mechanical allodynia were evaluated using ankle joint circumference measurement and von Frey filaments, respectively. Hv1 current, tail current, and action potential in dorsal root ganglion (DRG) neurons were recorded with patch-clamp techniques. RESULTS: HNK (10, 20, 40 mg/kg) alleviated inflammatory response and mechanical allodynia in a dose-dependent manner. In normal DRG neurons, 50 µM Zn2+ or 2-GBI significantly inhibited the Hv1 current and the current density of Hv1 increased with increasing pH gradient. The amplitude of Hv1 current significantly increased on the 3rd after MSU treatment, and HNK dose-dependently reversed the upregulation of Hv1 current. Compared with MSU group, 40 mg/kg HNK shifted the activation curve to the direction of more positive voltage and increased reversal potential to the normal level. In addition, 40 mg/kg HNK reversed the down-regulation of tail current deactivation time constant (τtail) but did not alter the neuronal excitability of DRG neurons in gouty mice. CONCLUSION: HNK may be a potential analgesic by inhibiting Hv1 current.