Advances in Experimental and Clinical Research of the Gouty Arthritis Treatment with Traditional Chinese Medicine

Elucidating the mechanism of the Tibetan medicine sanguotang in treating gouty arthritis through network pharmacology and in vivo experiments

BACKGROUND

We explored the mechanisms of Sanguotang (SGT), a Tibetan medicine, in treating gout arthritis (GA).

METHODS

The main active components, action targets, and disease targets of SGT were identified through TCMSP databases. The gene functions were analyzed using protein interaction (PPI) networks, Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and molecular docking. A GA model induced by monosodium urate was established in rats. The ankle joint swelling was observed. The levels of uric acid (UA) and albumin (ALB) in rat serum were measured. Hematoxylin and eosin (HE) staining was conducted to examine the pathological changes in rat ankle joints.

RESULTS

Twenty-nine active components of SGT with proven efficacy and 66 intersection targets were identified, primarily involved in inflammation and immune regulation pathways. The PPI results revealed that the key targets of SGT against GA included ALB, IL6, TNF, TP53, and PTGS. Molecular docking showed favorable binding energy between the ALB protein and the active components. The results from animal experiments demonstrated that SGT effectively alleviated the inflammatory reaction in ankle joints, and decreased UA and ALB levels. Furthermore, SGT effectively inhibited the proliferation of synovial cells in the ankle joint cavity, prevented infiltration of inflammatory cells, and protected synovial tissue, thereby improving GA.

CONCLUSIONS

SGT comprehensively contributes to the treatment of GA by regulating UA metabolism, reducing the release of inflammatory factors, and modulating immune and inflammatory pathways.

Herbal remedies in the management of hyperuricemia and gout: A review of in vitro, in vivo and clinical evidences

Gout, or hyperuricemia is a multifactorial and multi-faceted metabolic disease that is quite difficult to manage and/or treat. Conventional therapies such as non-steroidal anti-inflammatory drugs (NSAIDs) such as allopurinol, corticosteroids and colchicine amongst others, have helped in its management and treatment to some extent. This study aimed to compile and analyze the different herbal remedies used in the management of hyperuricemia and gout. A literature search was conducted from key databases (PubMed, ScienceDirect, Cochrane Library, Google Scholar) using relevant keywords via the PRISMA model. Smilax riparia A.DC. from Traditional Chinese Medicine is used in many countries for its therapeutic effect on lowering serum urate levels. No single study was able to establish the efficacy of a specific traditionally used herb via in vitro, in vivo, and clinical studies. Patients were found to use a panoply of natural remedies, mainly plants to treat hyperuricemia and gout, which have been validated to some extent by in vitro, in vivo, and clinical studies. Nonetheless, further research is needed to better understand the ethnopharmacological relationship of such herbal remedies.

Signaling pathways in uric acid homeostasis and gout: From pathogenesis to therapeutic interventions

Uric acid is a product of purine degradation, and uric acid may have multiple physiologic roles, including the beneficial effects as an antioxidant and neuroprotector, maintenance of blood pressure during low salt ingestion, and modulation of immunity. However, overproduction of metabolic uric acid, and/or imbalance of renal uric acid secretion and reabsorption, and/or underexcretion of extrarenal uric acid, e.g. gut, will contribute to hyperuricemia, which is a common metabolic disease. Long-lasting hyperuricemia can induce the formation and deposition of monosodium urate (MSU) crystals within the joints and periarticular structures. MSU crystals further induce an acute, intensely painful, and sterile inflammation conditions named as gout by NLRP3 inflammasome-mediated cleavage of pro-IL-1β to bioactive IL-1β. Moreover, hyperuricemia and gout are associated with multiple cardiovascular and renal disorders, e.g., hypertension, myocardial infarction, stroke, obesity, hyperlipidemia, type 2 diabetes mellitus and chronic kidney disease. Although great efforts have been made by scientists of modern medicine, however, modern therapeutic strategies with a single target are difficult to exert long-term positive effects, and even some of these agents have severe adverse effects. The Chinese have used the ancient classic prescriptions of traditional Chinese medicine (TCM) to treat metabolic diseases, including gout, by multiple targets, for more than 2200 years. In this review, we discuss the current understanding of urate homeostasis, the pathogenesis of hyperuricemia and gout, and both modern medicine and TCM strategies for this commonly metabolic disorder. We hope these will provide the good references for treating hyperuricemia and gout.

Anti-inflammatory and uric acid lowering effects of Euodiae fructus on hyperuricemia and gout mice

The metabolic disease hyperuricemia (HUA) is caused by presence of excessive serum uric acid (UA), which leads to an increased risk of chronic kidney disease and gout. As a widely used traditional Chinese medicine, Euodiae fructus (ER) has strong anti-inflammatory and analgesic effects, however, its therapeutic effects on HUA and gout have not been investigated. To investigate the potential effects and underlying mechanisms, the effect of ER on proinflammatory cytokines and NLRP3 inflammasome activation was studied in mouse bone marrow macrophages. Moreover, a mouse model of HUA and gouty arthritis was established by coadministration of potassium oxonate (PO) and monosodium urate crystals to mice fed a high-fat diet (HFD) for 37 consecutive days. Oral administration of ER aqueous extract was given 1 hour later after the injection of PO for 10 days. Our study showed that ER is a powerful NLRP3 inhibitor in mouse macrophages. Most importantly, ER (0.75 g/kg) treatment substantially decreased the ankle joint thickness ratio, serum UA, creatinine and blood urea nitrogen levels (p < 0.05). Additionally, ER (0.75 g/kg) dramatically reversed the increases in renal urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) as well as the decreases in organic anion transporter 1 (OAT1) and ATP binding cassette subfamily G member 2 (ABCG2) levels (p < 0.05). Moreover, ER (0.75 g/kg) markedly ameliorated the production of the serum inflammatory cytokines IL-1β and TNF-α (p < 0.01), and improved the activation of NLRP3 inflammasome signaling in the kidneys. Taken together, these data indicate that ER, a powerful and specific NLRP3 inhibitor, has multiple anti-HUA, anti-gout and anti-inflammatory effects. Our investigation is designed to experimentally support the conventional use of ER-containing classical herbal formulas in the treatment of HUA-related disorders and may add a new dimension to the clinical application of ER.

Pathogenesis of gout: Exploring more therapeutic target

Gout is a chronic metabolic and immune disease, and its specific pathogenesis is still unclear. When the serum uric acid exceeds its saturation in the blood or tissue fluid, it is converted to monosodium urate crystals, which lead to acute arthritis of varying degrees, urinary stones, or irreversible peripheral joint damage, and in severe cases, impairment of vital organ function. Gout flare is a clinically significant state of acute inflammation in gout. The current treatment is mostly anti-inflammatory analgesics, which have numerous side effects with limited treatment methods. Gout pathogenesis involves many aspects. Therefore, exploring gout pathogenesis from multiple perspectives is conducive to identifying more therapeutic targets and providing safer and more effective alternative treatment options for patients with gout flare. Thus, this article is of great significance for further exploring the pathogenesis of gout. The author summarizes the pathogenesis of gout from four aspects: signaling pathways, inflammatory factors, intestinal flora, and programmed cell death, focusing on exploring more new therapeutic targets.

Alterations in articular cartilage frictional properties in the setting of acute gouty arthritis

The tribological behaviour of articular cartilage plays a key role in joint motion; however, there is a gap in research on the effect of hyperuricemic joint fluid on cartilage friction behaviour in acute gouty arthritis. In this study, we carried out a fixed-load scratch experiment to compare the friction and wear of articular cartilage under the lubrication of gouty arthritis arthritic fluid and normal human arthritic fluid, and the results showed that the cartilage friction coefficient of patients with acute gouty arthritis was significantly larger than that of normal human beings, and that the cartilage friction coefficient decreased with the elevation of normal load and sliding speed, and the change with the sliding speed varied more differently from that of normal human beings, and that the cartilage surface wear was more severe after prolonged friction. The wear and tear of the cartilage surface is more severe after prolonged friction. Patients with gouty arthritis should reduce the sudden speed changes such as fast running and variable speed running to maintain the stability of the cartilage surface friction coefficient.

Exploring effect of herbal monomers in treating gouty arthritis based on nuclear factor-kappa B signaling: A review

Gouty arthritis (GA) is an inflammatory disease caused by disorders of the purine metabolism. Although increasing number of drugs have been used to treat GA with the deepening of relevant research, GA still cannot be cured by simple drug therapy. The nuclear factor-kappa B (NF-κB) signaling pathway plays a key role in the pathogenesis of GA. A considerable number of Chinese herbal medicines have emerged as new drugs for the treatment of GA. This article collected relevant research on traditional Chinese medicine monomers in the treatment of GA using NF-κB, GA, etc. as keywords; and conducted a systematic search of relevant published articles using the PubMed database. In this study, we analyzed the therapeutic effects of traditional Chinese medicine monomers on GA in the existing literature through in vivo and in vitro experiments using animal and cell models. Based on this review, we believe that traditional Chinese medicine monomers that can treat GA through the NF-κB signaling pathway are potential new drug development targets. This study provides research ideas for the development and application of new drugs for GA.

Modified Simiaowan prevents and treats gouty arthritis via the Nrf2/NLRP3 inflammasome signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Modified Simiaowan (MSM) is a six-herb formula that has been shown to be effective in gouty arthritis (GA) has been proven, but its regulatory mechanism has not been fully elucidated.

AIM OF THE STUDY

To investigate the therapeutic effects and mechanism of MSM on gouty arthritis.

MATERIALS AND METHODS

Mouse J774A.1 macrophages were induced with Lipopolysaccharide (LPS) and then stimulated with Adenosine 5'-triphosphate (ATP) or Nigericin (Nig.) in presence or absence of MSM. Expression of key indicators of pro-inflammatory cytokines and the NLRP3 inflammasome signaling pathway were investigated by western blot, ELISA and qRT-PCR. Fluorescence staining and flow cytometry were performed to detect intracellular reactive oxygen species (ROS) production. Another study, the anti-inflammatory and antioxidant activities of MSM were evaluated in rats with monosodium urate (MSU) -induced gouty arthritis using ELISA, hematoxylin-eosin staining (HE) staining, immunohistochemistry, and oxidative stress kits to measure relevant inflammatory markers and oxidative stress-related biomarkers.

RESULTS

ELISA and qRT-PCR results demonstrated that MSM effectively reduced the secretion and the mRNA expression levels of pro-inflammatory cytokines. Western blot results indicated that MSM can suppress the expression of NLRP3, an inflamasomes-related protein. In addition, MSM regulated the transition from M1 to M2 macrophages and upregulated the protein expression of Nrf2 and HO-1. The flow cytometry results and the fluorescence staining result were consistent with hypothesis that a large amount of ROS could be effectively cleared by MSM. However, the anti-inflammatory effect of MSM was attenuated after the use of ML385. In vivo experiments demonstrated that joint swelling was significantly attenuated and knee neutrophil infiltration was alleviated in rats given MSM. SOD and GSH-px levels were elevated significantly, while COX-2 and MDA levels decreased. The immunohistochemical results suggested that MSM could effectively inhibit the activation of the NLRP3 inflammasome and the regulation of macrophage polarization in rat synovial tissue, and remarkably enhance the expression of Nrf2 and HO-1.

CONCLUSION

MSM has potent anti-inflammatory and antioxidant effects on MSU-induced gouty arthritis. MSM alleviates GA through Nrf2/HO-1/ROS/NLRP3 signaling pathway.

Study of hispidulin in the treatment of uric acid nephropathy based on NF-κB signaling pathway

Uric acid nephropathy (UAN) is caused by purine metabolism disorders. UAN rat models were established in SD rats. The modeling rats received different doses of hispidulin (10, 20, 50 mg/mL). Febuxostat was applied as the positive drug. Serum creatinine, uric acid (UA), and cystatin-C (cys-C), neutrophil gelatinase-associated lipocalin (NGAL), IL-1β, IL-8, TNF-α, and IL-6 in rats were detected. HE staining was done to assess kidney injury. UAN rats possessed prominent levels of serum creatinine, UA, cys-C, and NGAL, which all reduced after hispidulin treatment in a dose-dependent manner. HE staining determined the improvement of kidney injury after treatment, which was comparable to the efficacy of febuxostat. Hispidulin inhibited the release of IL-1β, IL-8, TNF-α, and IL-6 in UAN rats. Hispidulin enhanced autophagy in UAN rats, presenting as ascending LC3II/I ratio and downregulated P62. The increasing trend of inflammasome-related proteins of NLRP3 and Caspase-1 was changeovered by hispidulin. The activation of NF-kB signaling was intercepted by hispidulin in UAN rats. Hispidulin can effectively improve renal function injury caused by UAN in rats. The mechanism may be related to the inhibition of inflammatory response induced by autophagy and activation of NF-κB pathway.

Influence of intestinal microecology in the development of gout or hyperuricemia and the potential therapeutic targets

Gout and hyperuricemia are common metabolic diseases. Patients with purine metabolism disorder and/or decreased uric acid excretion showed increased uric acid levels in the blood. The increase of uric acid in the blood leads to the deposition of urate crystals in tissues, joints, and kidneys, and causes gout. Recent studies have revealed that imbalance of the intestinal microecology is closely related to the occurrence and development of hyperuricemia and gout. Disorder of the intestinal flora often occurs in patients with gout, and high purine and high fructose may induce the disorder of intestinal flora. Short-chain fatty acids and endotoxins produced by intestinal bacteria are closely related to the inflammatory response of gout. This article summarizes the characteristics of intestinal microecology in patients or animal models with hyperuricemia or gout, and explores the relationship between intestinal microecology and gout or hyperuricemia from the aspect of the intestinal barrier, intestinal microorganisms, intestinal metabolites, and intestinal immune system. We also review the current status of hyperuricemia treatment by targeting intestinal microecology.

Network-Based Pharmacology and Bioinformatics Study on the Mechanism of Action of Gujiansan in the Treatment of Steroid-Induced Avascular Necrosis of the Femoral Head

Objective

To investigate the main pharmacological basis and mechanism of action of Gujiansan in the treatment of steroid-induced avascular necrosis of the femoral head (SANFH).

Methods

The active constituents and targets of Gujiansan were screened by using TCMSP and other databases, and relevant disease targets were obtained by analyzing the microarray of SANFH in the GEO database. The intersection of the two was taken to obtain the potential targets of Gujiansan for the treatment of SANFH, and key active constituents were screened with the “active constituent-target” network constructed by the Cytoscape software; then, the STRING database was used to construct the protein interaction network to screen the key targets. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses of key targets were performed by the DAVID database, and the relationship between the “key active constituent-key target-key signaling pathway” was explored. Finally, the molecular docking between key active constituents and key targets was verified. In addition, qPCR detection technology was used to evaluate the preventive and therapeutic effects of key active constituents of Gujiansan in a rat osteoblast model of SANFH to verify the possible mechanism of the effect of Gujiansan in the treatment of SANFH.

Results

(1) 106 active constituents and 55 targets were obtained for the treatment of SANFH. (2) Quercetin, luteolin, kaempferol, cryptotanshinone, and naringenin were the key active constituents for the treatment of SANFH. (3) IL1B, STAT3, CAT, PTGS2, and MAPK3 were the key targets for the treatment of SANFH. (4) IL1B, STAT3, CAT, PTGS2, MAPK3, and HMOX1 are key targets in the protein interaction network. (5) DAVID enrichment analysis mainly covers the regulation of DNA-binding transcription factor activity, positive regulation of cytokine production, and response to oxidative stress and other biological processes, involving IL-17, AGE-RAGE, C-type lectin receptor, and other signaling pathways. (6) Gujiansan is a multitarget and multisignaling pathway for the treatment of SANFH. (7) Good binding activity exists between key active constituents and key targets.

Conclusion

This study analyzes the potential mechanism of action of Gujiansan in the treatment of SANFH with network pharmacology, which can provide a reference for the further study of its pharmacological basis and targets.

Global Trends in Research of Gouty Arthritis Over Past Decade: A Bibliometric Analysis

Gouty arthritis (GA), as a multifactorial disease, is characterised by intense pain, active inflammation symptoms, and swollen joints. It has utterly complex pathogenesis, of which the amount of research publications on GA has increased during the last few decades. A bibliometric analysis was carried out to investigate the trends, frontiers, and hot spots in global scientific output in GA research over the last decade. We retrieved the Science Citation Index Expanded (SCI-Expanded) of the Web of Science Core Collection (WoSCC) for publications and recorded information published from 2012 to 2021. we carried out the bibliometric analysis and visualisation analysis of the overall distribution of annual outputs, leading countries, active institutions, journals, authors, co-cited references, and keywords with the VOSviewer and CiteSpace. The impact and quality of papers were assessed using a global citation score (GCS). We retrieved 2052 articles and reviews in total. The annual number of publications (Np) related to GA research has increased during the latest decade. China published the most papers, and the USA achieved the highest H-index and number of citations (Nc). The League of European Research Universities (LERU) and Clinical Rheumatology (Clin Rheumatol) are the most productive institutions and periodicals. The total GCS of the paper written by Kottgen, A. in 2013 was 479, ranking the first. The most common keywords were "Gout," "hyperuricemia," and "gouty arthritis." This research revealed that though there was a slight fluctuation in publications related to GA, the Np raised on the whole. China was an enormous creator, and the USA was an influential nation in this domain. The top three contributor authors were Dalbeth, N., Singh, JA., and Choi, HK. There were few investigations on the treatment of GA by Chinese medicine monomer, and the "mechanism," "pathway", "nf- kappa-b", "injury", "receptor", and "animal model" were growing research hotspots. Our research illustrated the hotspots of research and development trends in the research field of GA during the last decade. Recognition of the most critical indicators (researchers, countries, institutes, and journals for the release of GA research), hotspots in the research field of GA can be helpful for countries, scholars, and policymakers in this field to understand GA better make decisions.

Inflammatory Response to Regulated Cell Death in Gout and Its Functional Implications

Gout, a chronic inflammatory arthritis disease, is characterized by hyperuricemia and caused by interactions between genetic, epigenetic, and metabolic factors. Acute gout symptoms are triggered by the inflammatory response to monosodium urate crystals, which is mediated by the innate immune system and immune cells (e.g., macrophages and neutrophils), the NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome activation, and pro-inflammatory cytokine (e.g., IL-1β) release. Recent studies have indicated that the multiple programmed cell death pathways involved in the inflammatory response include pyroptosis, NETosis, necroptosis, and apoptosis, which initiate inflammatory reactions. In this review, we explore the correlation and interactions among these factors and their roles in the pathogenesis of gout to provide future research directions and possibilities for identifying potential novel therapeutic targets and enhancing our understanding of gout pathogenesis.