Therapeutic potential and pharmacological mechanisms of Traditional Chinese Medicine in gout treatment

Gout is a systemic metabolic disorder caused by elevated uric acid (UA) levels, affecting over 1% of the population. The most common complication of gout is gouty arthritis (GA), characterized by swelling, pain or tenderness in peripheral joints or bursae, which can lead to the formation of tophi. At present, western medicines like colchicine, febuxostat and allopurinol are the primary treatment strategy to alleviate pain and prevent flare-ups in patients with GA, but they have significant side effects and increased mortality risks. Traditional Chinese medicine (TCM) has been utilized for thousands of years for the prevention and treatment of GA, demonstrating effective control over serum UA (SUA) levels with fewer side effects. Herein we summarized a total of 541 studies published from 2000 to 2023 in sources including PubMed, Web of Science, the Cochrane Library and Embase, highlighting the therapeutic potential of TCM in treating gout and GA, particularly in combination with modern medical strategies. This review focuses on TCM formulas, Chinese herbal extracts, and active compounds derived from TCM, providing an overview of recent clinical application and the pharmacological research based on animal models and cellular systems. Particularly, the current review categorized the clinical and experimental evidence into the strategies for improving hyperuricemia, decreasing the sudden onset of acute GA and retarding chronic GA progression, supplied further coherent reference and enlightenment for clinicians, investigators of natural product chemistry, researchers in TCM and pharmacology. We hope this article will inspire the development of novel formulas and molecular entities for the treatment of gout and GA.

Mechanism of intestinal flora affecting SLC2A9 transport function to promote the formation of hyperuricemia

Objective

To investigate the structural characteristics of the intestinal flora in obese-hyperuricemic (HUA-W) patients and the mechanisms by which they promote the formation of hyperuricemia.

Methods

120 human fecal samples (60 cases in HC, 30 cases in HUA-N, and 30 cases in HUA-W) and 40 cases in the colonic tissues (20 cases in HC, 10 cases in HUA-N, and 10 cases in HUA-W) were collected. The intestinal flora of faeces was detected by 16s rRNA method; and the expression of SLC2A9 on human colon tissues was detected by RT-qPCR method and immunofluorescence method. 40 obese-hyperuricemia rat models were established (10 rats in Model, 10 rats in HC-FT, 10 rats in HUA-N-FT, and 10 rats in HUA-W-FT), and 10 rats were set up in Control; and the level of uric acid in rat serum, the levels of xanthine oxidase (XOD) activity and uric acid in intestinal fluid were examined. SLC2A9+ Caco-2 cells were produced to simulate the Transwell uric acid transport model, and the Caco-2 cells and SLC2A9+ Caco-2 cells were grown in five different culture media (Blank, Germ-free, HC-germ, HUA-N-germ and HUA-W-germ), and the uric acid levels in the upper and lower layers of the chambers were detected.

Results

The HUA-W intestinal flora showed significant specificity, with a decrease in Bacteroidota and Bacteroidia and an increase in Escherichia and Ruminococcus. There were no significant differences in the fluorescence intensity of the SLC2A9 protein and the SLC2A9 mRNA levels in the colon tissues of the HUA-N and HUA-W (P = 0.447, P = 0.152, P = 0.4799 and P = 0.965, respectively). In rat animal experiments, uric acid levels were significantly higher (P < 0.05) and XOD activity was significantly higher (P < 0.05) in intestinal fluid of HUA-W-FT. In Transwell experiments with SLC2A9+ Caco-2 cells, uric acid levels were increased in the upper compartment and decreased in the lower compartment of HUA-W-germ.

Conclusion

HUA-W intestinal flora may increase XOD activity in the intestinal tract and improve the ability of uric acid transporter protein SLC2A9 to reabsorb uric acid, providing a new theoretical basis for the pathogenesis of hyperuricemia.

Regulating Lipid Metabolism in Gout: A New Perspective with Therapeutic Potential

Gout is a metabolic disease characterized by inflammatory arthritis caused by abnormal uric acid metabolism. It is often complicated with cardio-renal damage and vascular lesions. In recent years, the relationship between lipid metabolism and gout has attracted increasing attention. Changes in blood lipids in gout patients are often clinically detectable and closely related to uric acid metabolism and inflammatory response in gout. With the development of lipidomics, the changes in small lipid molecules and their metabolic pathways have been gradually discovered, yielding a greater understanding of the lipid metabolism changes in gout patients and their potential role in gout development. Through searching the literature on lipid metabolism in gout since 2000 in PubMed and Web of Science, this article reviewed lipid metabolism changes in gout patients and their role in the risk of gout, uric acid metabolism, inflammatory response, and comorbidities. Additionally, the strategies to regulate the abnormal lipid metabolism in gout have also been summarized from the aspects of drugs, diet, and exercise. These will provide a new perspective for understanding gout pathogenesis and its treatment and management.

The Therapeutic Management of Chemical and Herbal Medications on Uric Acid Levels and Gout: Modern and Traditional Wisdom

Background: Gout is a chronic inflammatory condition characterized by elevated uric acid levels in the blood, which can precipitate acute gout attacks in individuals with genetic susceptibility, existing medical conditions, and dietary influences. Genetic predispositions, comorbid medical conditions, nutritional choices, and environmental factors increasingly recognize the multifactorial etiology of the disease. Methods: Recent research has highlighted the potential of phytochemicals, particularly flavonoids, saponins, and alkaloids, to manage hyperuricemia (HUA) and its associated complications. Results: Plant's natural compounds have garnered attention for their anti-inflammatory, antioxidant, and uric acid-lowering properties, suggesting their role in alternative and complementary medicine. Phytochemicals have demonstrated promise in mitigating gout symptoms and potentially modifying the disease course by addressing different aspects of hyperuricemia and inflammation. Herbal remedies, with their complex phytochemical profiles, offer a unique advantage by potentially complementing conventional pharmacological treatments. The integration of herbal therapies with standard medications could lead to enhanced therapeutic outcomes through synergistic effects, optimizing disease management, and improving patient quality of life. Conclusions: This review examines the current understanding of the multifaceted etiology of gout, explores the role of phytochemicals in managing hyperuricemia, and discusses the potential benefits of combining herbal remedies with conventional treatments to improve patient care and therapeutic efficacy.

Gut microecology: effective targets for natural products to modulate uric acid metabolism

Gut microecology,the complex community consisting of microorganisms and their microenvironments in the gastrointestinal tract, plays a vital role in maintaining overall health and regulating various physiological and pathological processes. Recent studies have highlighted the significant impact of gut microecology on the regulation of uric acid metabolism. Natural products, including monomers, extracts, and traditional Chinese medicine formulations derived from natural sources such as plants, animals, and microorganisms, have also been investigated for their potential role in modulating uric acid metabolism. According to research, The stability of gut microecology is a crucial link for natural products to maintain healthy uric acid metabolism and reduce hyperuricemia-related diseases. Herein, we review the recent advanced evidence revealing the bidirectional regulation between gut microecology and uric acid metabolism. And separately summarize the key evidence of natural extracts and herbal formulations in regulating both aspects. In addition,we elucidated the important mechanisms of natural products in regulating uric acid metabolism and secondary diseases through gut microecology, especially by modulating the composition of gut microbiota, gut mucosal barrier, inflammatory response, purine catalyzation, and associated transporters. This review may offer a novel insight into uric acid and its associated disorders management and highlight a perspective for exploring its potential therapeutic drugs from natural products.

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.

Research progress of treating hyperuricemia in rats and mice with traditional Chinese medicine

Hyperuricemia (HUA) is a common chronic metabolic disease caused by abnormal purine metabolism and uric acid excretion. Despite extensive research on HUA, no clear treatment has been found so far. Improving purine metabolism and promoting uric acid excretion is crucial for the effective treatment of HUA. In recent years, traditional Chinese medicine and traditional Chinese medicine prescriptions have shown good effects in treating HUA. This article summarizes the latest progress in treating HUA in rats and mice using traditional Chinese medicine and prescriptions, elaborates on the pathogenesis of HUA, explores the application of commonly used traditional Chinese medicine treatment methods and prescriptions, and discusses the previous pharmacological mechanisms. In general, our research indicates that traditional Chinese medicine can effectively relieve the symptoms related to elevated uric acid levels in HUA rats and mice. However, further exploration and research are needed to verify its efficacy, safety, and feasibility.

The Bioactive Compounds of Epimedium and Their Potential Mechanism of Action in Treating Osteoporosis: A Network Pharmacology and Experimental Validation Study

Osteoporosis is a global health challenge characterized by bone loss and microstructure deterioration, which urgently requires the development of safer and more effective treatments due to the significant adverse effects and limitations of existing drugs for long-term treatment. Traditional Chinese medicine, like Epimedium, offers fewer side effects and has been used to treat osteoporosis, yet its active compounds and pharmacological mechanisms remain unclear. In this study, 65 potential active compounds, 258 potential target proteins, and 488 pathways of Epimedium were identified through network pharmacology analysis. Further network analysis and review of the literature identified six potential active compounds and HIF-1α for subsequent experimental validation. In vitro experiments confirmed that 2″-O-RhamnosylIcariside II is the most effective compound among the six potential active compounds. It can promote osteoblast differentiation, bind with HIF-1α, and inhibit both HIF-1α gene and protein expression, as well as enhance COL1A1 protein expression under hypoxic conditions. In vivo experiments demonstrated its ability to improve bone microstructures and reduce bone loss by decreasing bone marrow adipose tissue, enhancing bone formation, and suppressing HIF-1α protein expression. This study is the first to describe the therapeutic effects of 2-O-RhamnosylIcariside II on osteoporosis, which was done, specifically, through a mechanism that targets and inhibits HIF-1α. This study provides a scientific basis for the clinical application of Epimedium and offers a new candidate drug for the treatment of osteoporosis. Additionally, it provides new evidence supporting HIF-1α as a therapeutic target for osteoporosis.

Renal interstitial fibrotic assessment using non-Gaussian diffusion kurtosis imaging in a rat model of hyperuricemia

BACKGROUND

To investigate the feasibility of Diffusion Kurtosis Imaging (DKI) in assessing renal interstitial fibrosis induced by hyperuricemia.

METHODS

A hyperuricemia rat model was established, and the rats were randomly split into the hyperuricemia (HUA), allopurinol (AP), and AP + empagliflozin (AP + EM) groups (n = 19 per group). Also, the normal rats were selected as controls (CON, n = 19). DKI was performed before treatment (baseline) and on days 1, 3, 5, 7, and 9 days after treatment. The DKI indicators, including mean kurtosis (MK), fractional anisotropy (FA), and mean diffusivity (MD) of the cortex (CO), outer stripe of the outer medulla (OS), and inner stripe of the outer medulla (IS) were acquired. Additionally, hematoxylin and eosin (H&E) staining, Masson trichrome staining, and nuclear factor kappa B (NF-κB) immunostaining were used to reveal renal histopathological changes at baseline, 1, 5, and 9 days after treatment.

RESULTS

The HUA, AP, and AP + EM group MKOS and MKIS values gradually increased during this study. The HUA group exhibited the highest MK value in outer medulla. Except for the CON group, all the groups showed a decreasing trend in the FA and MD values of outer medulla. The HUA group exhibited the lowest FA and MD values. The MKOS and MKIS values were positively correlated with Masson's trichrome staining results (r = 0.687, P < 0.001 and r = 0.604, P = 0.001, respectively). The MDOS and FAIS were negatively correlated with Masson's trichrome staining (r = -626, P < 0.0014 and r = -0.468, P = 0.01, respectively).

CONCLUSION

DKI may be a non-invasive method for monitoring renal interstitial fibrosis induced by hyperuricemia.

Gut-immunity-joint axis: a new therapeutic target for gouty arthritis

Gouty arthritis (GA) is an inflammatory disease characterized by pain. The primary goal of current treatment strategies during GA flares remains the reduction of inflammation and pain. Research suggests that the gut microbiota and microbial metabolites contribute to the modulation of the inflammatory mechanism associated with GA, particularly through their effect on macrophage polarization. The increasing understanding of the gut-joint axis emphasizes the importance of this interaction. The primary objective of this review is to summarize existing research on the gut-immune-joint axis in GA, aiming to enhance understanding of the intricate processes and pathogenic pathways associated with pain and inflammation in GA, as documented in the published literature. The refined comprehension of the gut-joint axis may potentially contribute to the future development of analgesic drugs targeting gut microbes for GA.

Herbal medicine and gut microbiota: exploring untapped therapeutic potential in neurodegenerative disease management

The gut microbiota that exists in the human gastrointestinal tract is incredibly important for the maintenance of general health as it contributes to multiple aspects of host physiology. Recent research has revealed a dynamic connection between the gut microbiota and the central nervous system, that can influence neurodegenerative diseases (NDs). Indeed, imbalances in the gut microbiota, or dysbiosis, play a vital role in the pathogenesis and progression of human diseases, particularly NDs. Herbal medicine has been used for centuries to treat human diseases, including NDs. These compounds help to relieve symptoms and delay the progression of NDs by improving intestinal barrier function, reducing neuroinflammation, and modulating neurotransmitter production. Notably, herbal medicine can mitigate the progression of NDs by regulating the gut microbiota. Therefore, an in-depth understanding of the potential mechanisms by which herbal medicine regulates the gut microbiota in the treatment of NDs can help explain the pathogenesis of NDs from a novel perspective and propose novel therapeutic strategies for NDs. In this review, we investigate the potential neuroprotective effects of herbal medicine, focusing on its ability to regulate the gut microbiota and restore homeostasis. We also highlight the challenges and future research priorities of the integration of herbal medicine and modern medicine. As the global population ages, access to this information is becoming increasingly important for developing effective treatments for these diseases.

Traditional Chinese Medicine in Osteoporosis Intervention and the Related Regulatory Mechanism of Gut Microbiome

The gut microbiome (GM) has become a crucial factor that can affect the progression of osteoporosis. A number of studies have demonstrated the impact of Traditional Chinese Medicine (TCM) on GM and bone metabolism. In this review, we summarize the potential mechanisms of the relationship between osteoporosis and GM disorder and introduce several natural Chinese medicines that exert anti-osteoporosis effects by modulating the GM. It is underlined that, through the provision of the microbial associated molecular pattern (MAMP), the GM causes inflammatory reactions and alterations in the Treg-Th17 balance and ultimately leads to changes in bone mass. Serotonin and many hormones, especially estrogen, may play a crucial role in the interaction of the GM with bone metabolism. Additionally, the GM may affect the absorption of specific nutrients in the intestine, particularly minerals like calcium, magnesium, and phosphorus. Several natural Chinese herbs, such as Sambucus Williamsii, Achyranthes bidentata Blume, Pleurotus ostreatus and Ganoderma lucidum mushrooms, Pueraria Lobata, and Agaricus blazei Murill have exhibited anti-osteoporosis effects through regulating the distribution and metabolism of the GM. These herbs may increase the abundance of Firmicutes, decrease the abundance of Bacteroides, promote the GM to produce more SCFAs, modulate the immune response caused by harmful bacteria, and increase the proportion of Treg-Th17 to indirectly affect bone metabolism. Moreover, gut-derived 5-HT is an important target for TCM to prevent osteoporosis via the gut-bone axis. Puerarin could prevent osteoporosis by improving intestinal mucosal integrity and decrease systemic inflammation caused by estrogen deficiency.

Chinese Herbal Extracts Mitigate Ammonia Generation in the Cecum of Laying Hens: An In Vitro Study

The objectives of the study were to screen one or several Chinese herbal extracts with good ammonia emission reduction effects using an in vitro gas production study. The study consisted of a control (without Chinese herbal extract), and 11 experimental groups with added cinnamon extract (CE), Osmanthus extract (OE), tangerine peel extract (TPE), dandelion extract (DE), Coptis chinensis extract (CCE), honeysuckle extract (HE), Pulsatilla root extract (PRE), yucca extract (YE), licorice extract (LE), Ginkgo biloba extract (GBE), or astragalus extract (AE). The results showed that HE, PRE, YE, LE, GBE, and AE significantly reduced ammonia production (p ≤ 0.05). The most significant ammonia inhibition was achieved via AE, resulting in a 26.76% reduction. In all treatments, Chinese herbal extracts had no significant effect on pH, conductivity, or uric acid, urea, and nitrate-nitrogen concentrations (p > 0.05). However, AE significantly reduced urease activity and the relative activity of uricase (p ≤ 0.05). AE significantly increased the relative abundance of Bacteroides and decreased the relative abundance of Clostridium, Desulfovibrio, and Prevotell (p ≤ 0.05). Astragalus extract inhibited ammonia emission from laying hens by changing the gut microbial community structure, reducing the relative abundance of ammonia-producing bacteria, and reducing microorganisms' uricase and urease activities.

16S rRNA and Metagenomics Combined with UPLC-Q/TOF-MS Metabolomics Analysis Reveals the Potential Mechanism of Radix Astragali Against Hyperuricemia in Mice

Purpose

This study aimed to investigate the underlying treatment mechanism of Radix Astragali (RA) in hyperuricemia from the perspective of microbiota and metabolomics.

Methods

We used potassium oxyazinate (PO) to induce hyperuricemia mice, and we determined serum alanine aminotransferase/aspartate aminotransferase (ALT/AST), xanthine oxidase (XOD), creatinine (CRE), uric acid (UA), blood urea nitrogen (BUN) levels, liver XOD levels and assessed the kidney tissue histopathology. The therapeutic mechanism of RA in hyperuricemic mice was studied by 16S rRNA, metagenomic sequencing and metabolomics.

Results

Our research showed that RA has therapeutic effect in hyperuricemia mice, such as slow the weight loss, repair kidney damage, and downregulate serum UA, XOD, CRE, ALT/AST, BUN, and liver XOD levels. RA restored the disturbance structure of the microbiota in hyperuricemia mice by increasing the relative abundances of beneficial bacteria (Lactobacillaceae and Lactobacillus murine) but decreasing the relative abundances of pathogenic bacteria (Prevotellaceae, Rikenellaceae and Bacteroidaceae). Meanwhile, we found that RA directly regulated the metabolic pathway (such as linoleic acid metabolism and glycerophospholipid metabolism) and indirectly regulated bile acid metabolism by mediating microbiota to ameliorate metabolic disorders. Subsequently, there was a robust correlation between specific microbiota, metabolites and the disease index.

Conclusion

The ability of RA to protect mice against hyperuricemia is strongly linked to the microbiome-metabolite axis, which would provide evidence for RA as a medicine to prevent or treat hyperuricemia.

Microbiota as a new pathogenetic factor in the development of chronic hyperuricemia and gout. Part 2: gout therapy and the gut microbiota

The article presents current data on the effect of drugs for the treatment of gout on the composition and function of the intestinal microbiota. The potential possibilities of pre- and probiotics use for the prevention and complex therapy of gout are discussed, therapeutic effect may be associated with their impact on the uric acid synthesis and intestinal excretion, as well as with anti-inflammatory properties. The need for further research in this area is emphasized.