Er Miao San, a traditional Chinese herbal formula, attenuates complete Freund's adjuvant-induced arthritis in rats by regulating Th17/Treg cells

TLR3 as an emerging molecule facilitating pyroptosis in the context of rheumatoid arthritis: A study combined bioinformatics and experimental validation

BACKGROUND

Rheumatoid arthritis (RA) is an inflammatory disease of the joints mediated by immune cells. As an immune-related mode of cell death, pyroptosis has yet to be fully understood in RA. This research identified novel pyroptosis-related markers in RA and confirmed its functional significance in RA.

METHODS

Initially, crucial pyroptosis-related genes of RA were identified through GEO database, and biological pathways were determined through enrichment analysis. Then, PPI network, WGCNA and CIBERSORT analysis was utilized to screen hub genes and evaluate immune cell infiltration levels. Finally, validation experiments determined hub genes expression and regulatory roles in RA pathogenesis, and screened potential therapeutic drugs.

RESULTS

A total of 46 DEPRGs in RA were identified, which involved in NOD-like receptor and Toll-like receptor signaling pathway. Further screening revealed 3 crucial hub genes: CCL5, LY96, and TLR3 had significantly increased expression in RA synovial tissue and FLS, which might become diagnostic markers of RA. Analysis of immune infiltration revealed that hub genes exhibited associations with plasma cells, T lymphocytes, and macrophages. Further study on the crucial hub gene TLR3 revealed that knocking down TLR3 significantly inhibited the RA FLS hyperproliferation and pyroptosis, and dexamethasone and doxorubicin, as potential drugs, could treat RA by inhibiting TLR3.

CONCLUSION

Our study indicates that high expression of TLR3 promotes FLS pyroptosis and RA progression, suggesting its potential as both a biomarker and a therapeutic target for RA.

Potential mechanisms of rheumatoid arthritis therapy: Focus on macrophage polarization

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that affects multiple organs and systems in the human body, often leading to disability. Its pathogenesis is complex, and the long-term use of traditional anti-rheumatic drugs frequently results in severe toxic side effects. Therefore, the search for a safer and more effective antirheumatic drug is extremely important for the treatment of RA. As important immune cells in the body, macrophages are polarized. Under pathological conditions, macrophages undergo proliferation and are recruited to diseased tissues upon stimulation. In the local microenvironment, they polarize into different types of macrophages in response to specific factors and perform unique functions and roles. Previous studies have shown that there is a link between macrophage polarization and RA, indicating that certain active ingredients can ameliorate RA symptoms through macrophage polarization. Notably, Traditional Chinese medicine (TCM) monomer component and compounds demonstrate a particular advantage in this process. Building upon this insight, we reviewed and analyzed recent studies to offer valuable and meaningful insights and directions for the development and application of anti-rheumatic drugs.

The role of macrophage polarization in rheumatoid arthritis and osteoarthritis: Pathogenesis and therapeutic strategies

Rheumatoid arthritis (RA) and osteoarthritis (OA) are common and debilitating joint disorders affecting millions of individuals worldwide. Despite their distinct pathological features, both conditions share a crucial role of macrophages in disease progression. Macrophages exhibit remarkable plasticity, polarizing into pro-inflammatory M1 or anti-inflammatory M2 phenotypes in response to environmental cues. An imbalance in macrophage polarization, particularly a shift towards the M1 phenotype, contributes to chronic inflammation and joint damage in RA and OA. This review explores the complex interplay between macrophages and various cell types, including T cells, B cells, synovial fibroblasts, osteoclasts, chondrocytes, and adipocytes, in the pathogenesis of these diseases. We discuss the current understanding of macrophage polarization in RA and OA, highlighting the molecular mechanisms involved. Furthermore, we provide an overview of potential therapeutic strategies targeting macrophage polarization, such as disease-modifying anti-rheumatic drugs, traditional Chinese medicine, nanomedicines, proteins, chemical compounds, and physical therapies. By elucidating the precise mechanisms governing macrophage polarization and its interactions with other cells in the joint microenvironment, researchers can identify novel therapeutic targets and develop targeted interventions to alleviate disease progression and improve patient outcomes in RA and OA.

Mechanic study based on untargeted metabolomics of Pi-pa-run-fei-tang on pepper combined with ammonia induced chronic cough model mice

ETHNOPHARMACOLOGICAL RELEVANCE

Pi-pa-run-fei-tang (PPRFT), a traditional Chinese medicine formula with long-standing history, demonstrated beneficial effect on chronic cough. However, the mechanism underlying efficacy unclear. In current research, we explored the impact and molecular mechanism of chronic cough mouse stimulating with capsaicin combined with ammonia.

AIM OF THE STUDY

To investigate the metabolic modulating effects, and potential mechanisms underlying the therapeutic effect of PPRFT in chronic cough.

MATERIALS AND METHODS

Chronic cough mouse models were created by stimulating mice by capsaicin combined with ammonia. Number of coughs and cough latency within 2 min were recorded. With lung tissue and serum samples collected for histopathology, metabolomics, RT-qPCR, immunohistochemistry, and WB analysis. Lymphocytes were isolated and flow cytometric assays were conducted to evaluate the differentiation between Th17 and Treg cell among CD4+ cells.

RESULTS

Results indicated that PPRFT obviously reduced the number of coughs, prolonged cough latency, reduced inflammatory cell infiltration and lung tissues damage, and decreased the serum level of IL-6, IL-1β, TNF-α, and IL-17 while increasing IL-10 levels. Notably, PPRFT suppressed Th17 cell divergence and promoted Treg cell divergence. Furthermore, serum metabolomic assays showed that 46 metabolites differed significantly between group, with 35 pathways involved. Moreover, mRNA levels of IL-6, NF-κB, IL-17, RORγT, JAK2, STAT3, PI3K and AKT in lung tissues remarkably reduced and mRNA levels of IL-10 and FOXP3 were elevated after PPRFT pretreatment. Additionally, PPRFT treatments decreased the protein levels of IL-6, NF-κB, IL-17, RORγT, p-JAK2, p-STAT3, p-PI3K, and p-AKT and increased the protein levels of IL-10 and FOXP3, but no significantly effects to the levels on JAK2, STAT3, PI3K, and AKT in the lungs.

CONCLUSION

Conclusively, our result suggested the effect with PPRFT on chronic cough may be mediated through IL-6/JAK2/STAT3 and PI3K/AKT/NF-κB pathway, which regulate the differentiation between Th17 and Treg cell. This beneficial effect of PPRFT in capsaicin and ammonia-stimulated chronic cough mice indicates its potential application in treating chronic cough.

Wnt/β-catenin signaling pathway promotes abnormal activation of fibroblast-like synoviocytes and angiogenesis in rheumatoid arthritis and the intervention of Er Miao San

BACKGROUND

Er Miao San (EMS) is an important herbal formula and a representative prescription for the treatment of the downwards flow of damp-heat syndrome. Clinical practice has proven that EMS can effectively treat rheumatoid arthritis (RA). Previous studies have demonstrated that EMS regulates the functions of T cells and dendritic cells and affects the polarization of macrophages. However, it is not clear whether the inhibitory effect of EMS on RA is related to the regulation of abnormal synovial activation and angiogenesis.

PURPOSE

The aim of this study was to elucidate the effect and potential mechanisms of EMS on the abnormal activation and angiogenesis of fibroblast-like synoviocytes (FLSs) in RA.

METHODS

The effect of EMS on rats with adjuvant arthritis (AA) and MH7A cells was examined by X-ray, haematoxylin-eosin (HE) staining, immunohistochemistry (IHC), ELISA and western blotting. Angiogenesis in AA rats was measured by a small animal ultrasound imaging system, immunofluorescence (IF) analysis and ELISA. An exchange between MH7A cells and HUVECs was induced using conditioned media that mimicked the microenvironment in vivo. CCK-8, western blotting, and scratch healing and Transwell migration assays were used to evaluate the effect of EMS on the Wnt/β-catenin signaling pathway and angiogenesis in the inflammatory microenvironment of RA.

RESULTS

Our results showed that EMS had a protective effect on AA rats. On the one hand, there was a decrease in paw swelling, the arthritis index, organ indices and proinflammatory factor levels, as well as relief of joint damage. On the other hand, blood flow, the number of immature blood vessels and proangiogenic factors were decreased. Furthermore, EMS reduced the expression of the Wnt/β-catenin signaling pathway in the synovial tissue of AA rats and MH7A cells. In the inflammatory microenvonrment of RA, the results were consistent.

CONCLUSION

This study demonstrated that EMS could protect against RA by inhibiting the abnormal activation and angiogenesis of FLSs, and the mechanism may be related to inhibiting the activation of the Wnt/β-catenin signaling pathway.

New Potentiality of Bioactive Substances: Regulating the NLRP3 Inflammasome in Autoimmune Diseases

The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is an essential component of the human innate immune system, and is closely associated with adaptive immunity. In most cases, the activation of the NLRP3 inflammasome requires priming and activating, which are influenced by various ion flux signals and regulated by various enzymes. Aberrant functions of intracellular NLRP3 inflammasomes promote the occurrence and development of autoimmune diseases, with the majority of studies currently focused on rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis. In recent years, a number of bioactive substances have shown new potentiality for regulating the NLRP3 inflammasome in autoimmune diseases. This review provides a concise overview of the composition, functions, and regulation of the NLRP3 inflammasome. Additionally, we focus on the newly discovered bioactive substances for regulating the NLRP3 inflammasome in autoimmune diseases in the past three years.

Prevention and treatment of inflammatory arthritis with traditional Chinese medicine: Underlying mechanisms based on cell and molecular targets

Inflammatory arthritis, primarily including rheumatoid arthritis, osteoarthritis and ankylosing spondylitis, is a group of chronic inflammatory diseases, whose general feature is joint dysfunction with chronic pain and eventually causes disability in older people. To date, both Western medicine and traditional Chinese medicine (TCM) have developed a variety of therapeutic methods for inflammatory arthritis and achieved excellent results. But there is still a long way to totally cure these diseases. TCM has been used to treat various joint diseases for thousands of years in Asia. In this review, we summarize clinical efficacies of TCM in inflammatory arthritis treatment after reviewing the results demonstrated in meta-analyses, systematic reviews, and clinical trials. We pioneered taking inflammatory arthritis-related cell targets of TCM as the entry point and further elaborated the molecular targets inside the cells of TCM, especially the signaling pathways. In addition, we also briefly discussed the relationship between gut microbiota and TCM and described the role of drug delivery systems for using TCM more accurately and safely. We provide updated and comprehensive insights into the clinical application of TCM for inflammatory arthritis treatment. We hope this review can guide and inspire researchers to further explore mechanisms of the anti-arthritis activity of TCM and make a great leap forward in comprehending the science of TCM.

Chemical compositions of Souliea vaginata (Maxim) Franch rhizome and their potential therapeutic effects on collagen-induced arthritis in rats

ETHNOPHARMACOLOGICAL REVEVANCE

Rheumatoid arthritis (RA) is a global prevalent chronic autoimmune inflammatory disease and acceptable safety drugs are lack for its treatment. The rhizomes of Souliea vaginata (Maxim) Franch (SV) possess anti-inflammatory functions and are used as substitution of Coptis chinensis Franch. SV is also traditional Chinese medicine and Tibetan medicine for the treatment of conjunctivitis, enteritis and rheumatic. For searching complementary and alternative anti-RA drugs, it is necessary to characterize the potential anti-arthritic activity of SV and underlying mechanism involved.

AIM OF THE STUDY

The aim of the study was to test the chemical compositions, evaluate the anti-arthritic effects and underlying mechanisms of SV.

MATERIALS AND METHODS

The chemical compositions of SV were analyzed using liquid chromatography-ion trap-time of flight tandem mass spectrometry (LCMS-IT-TOF). From day 11 to day 31, SV (0.5, 1.0 and 1.5 g/kg body weight) and Tripterygium glycosidorum (TG, 10 mg/kg body weight) were administered orally to the CIA model rats once a day. Thickness of paw and body weights were measured once every two days from day 1 to day 31. Histopathological changes were measured using hematoxylin-eosin (HE) staining. Effects of SV on the levels of IL-2, TNF-α, IFN-γ, IL-4 and IL-10 in serum of CIA rats were measured by enzyme-linked immunosorbent assay (ELISA) kits. CD3⁺, CD4⁺, CD8⁺ and CD4⁺CD25⁺ T cells populations were measured using flow cytometric analysis. To evaluate the possible hepatotoxicity and nephrotoxicity, the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea (UREA) and creatinine (CREA) in CIA rats were also tested using blood auto analyzer.

RESULTS

34 compounds were identified from SV based on LCMS-IT-TOF, and triterpenoids are major anti-arthritic compositions. SV significantly relieved CIA rats' paw swelling without obvious influence on the body weight growth. SV decreased the serum levels of IL-2, TNF-α and IFN-γ in CIA rat, and increased the serum levels of IL-4 and IL-10. SV significantly increased and decreased the percentages of CD4⁺ and CD8⁺, with no significant effects on CD3⁺ in lymphocytes of CIA model rats. Moreover, SV simultaneously decreased thymus and spleen indexes and no hepatotoxicity and nephrotoxicity was observed after short-term treatment.

CONCLUSION

These findings suggest that SV possesses preventive and therapeutic effect on RA by modulating the inflammatory cytokines, T-lymphocyte, thymus and spleen indexes and shows no hepatotoxicity and nephrotoxicity.

Exploring the effect of Er miao San-containing serum on macrophage polarization through miR-33/NLRP3 pathway

HEADINGS ETHNOPHARMACOLOGICAL RELEVANCE

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Er miao San (EMS) has been shown to have good anti-inflammatory effects and is widely used in the clinical treatment of RA. However, the exact mechanism is not completely understood.

AIM OF THE STUDY

The aim of this study was to explore that EMS-containing serum affects M1/M2 polarization of macrophages and may be mediated through the microRNA (miRNA)-33/NLRP3 pathway, thereby elucidating the molecular mechanism of EMS treatment of RA.

MATERIALS AND METHODS

We screened for safe concentrations of EMS-containing serum by using CCK-8 measurement. RAW264.7 cells were cultured with lipopolysaccharide (LPS) (100 ng/mL) and interferon-γ (20 ng/mL) for 24 h to induce M1-type macrophages. Adenosine triphosphate (ATP) (5 mM) was added in the last 30 min to activate NLRP3. The content of miR-33 was detected by RT‒qPCR after transfection of the miRNA-33 mimic. The protein expression levels of NLRP3, ASC, caspase-1, Inducible Nitric Oxide Synthase (iNOS) and Arginase-1 (Arg-1) were detected by Western blot. The contents of IL-1β, IL-10, TNF-α, TGF-β and IL-18 in serum and cell supernatant were determined by ELISA. The fluorescence intensity of CD86 and CD206 was detected by immunofluorescence.

RESULTS

The results showed that EMS-containing serum promoted the protein expression level of Arg-1 and the secretion levels of TGF-β and IL-10, inhibited the levels of iNOS, IL-1β and TNF-α, and regulated the balance of pro-inflammatory factors and anti-inflammatory factors. RT‒qPCR results showed that EMS-containing serum could reduce the level of miRNA-33. EMS-containing serum could reduce the expression of NLRP3 inflammasome-related proteins and downregulate the expression levels of IL-1β and IL-18. These results suggest that EMS exerts its effect on macrophage polarization through the miRNA-33/NLRP3 pathway.

CONCLUSION

EMS-containing serum inhibits the activation of the NLRP3 inflammasome by downregulating miRNA-33, thus preventing the polarization of M1-type macrophages.

Network pharmacology, molecular docking, and experimental pharmacology explored Ermiao wan protected against periodontitis via the PI3K/AKT and NF-κB/MAPK signal pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Ermiao Wan (EMW), a classic and famous traditional Chinese medicine (TCM)-based herbal formula combined Phellodendron chinense C.K.Schneid. (Cortex Phellodendri Chinsis, CP) and Atractylodes lancea (Thunb.) DC. (Rhizoma Atractylodis, RA) with the weight composition of 1:1, has been used for the treatment of periodontitis in China for a long time. However, its efficacy and mechanism of action are still unclear now.

AIM OF THE STUDY

This study explored the efficacy and pharmaceutical mechanism of action of EMW against periodontitis.

MATERIALS AND METHODS

The efficacy of EMW against periodontitis was evaluated using the ligature-induced periodontitis (LIP) mice, and inflammatory-related factors in gingiva and alveolar bone loss were determined using the qRT-PCR and micro-CT assays. The potential pharmacological mechanisms were predicted by bioinformatics analysis and further confirmed by the qRT-PCR and western blotting assays.

RESULTS

EMW exhibited inhibitory effects on periodontitis in the LIP mice. Bio-informational analysis showed the core compounds (berberine and chlorogenic acid) targeted the key genes (AKT, MAPK1, MAPK14, NF-κB, TNF, IL-2, and IL1B) through regulating the PI3K/AKT and NF-κB/MAPK signal pathways, which were validated using the qRT-PCR and western blotting assays.

CONCLUSIONS

EMW could eliminate alveolar bone loss and inhibit inflammation, thereby preventing the development of periodontitis. The mechanism of action may be achieved by regulating the PI3K/AKT and NF-κB/MAPK signal pathways. Therefore, EMW was a potential therapy for the treatment of periodontitis.

Xinfeng capsule inhibits inflammation and oxidative stress in rheumatoid arthritis by up-regulating LINC00638 and activating Nrf2/HO-1 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Xinfeng capsule is a traditional Chinese medicine compound, which has been clinically used for more than 20 years in the treatment of rheumatoid arthritis (RA), ankylosing spondylitis, osteoarthritis and its extracurricular lesions. However, the molecular role of XFC in the treatment of RA remains unclear.

OBJECTIVE

This study aims to explore the efficacy and potential mechanism of XFC through retrospective data mining analysis, animal experiments and cell experiments.

METHODS

The effect of XFC on clinical laboratory indexes of RA patients was observed using data mining techniques combined with association rule analysis and a random walk model. Afterwards, a rat model of adjuvant arthritis (AA) was established with Freund's complete adjuvant, followed by the observation of pathological changes in synovial tissues and the ultrastructure of synoviocytes. A RA cell model was constructed by inducing fibroblast-like synoviocytes (FLSs) with tumor necrosis factor-alpha (TNF-α) to assess the effects of XFC-containing serum on inflammation and oxidative stress through long non-coding RNA LINC00638.

RESULTS

In retrospective data mining, XFC effectively reduced immune inflammation and increase the level of antioxidant enzymes in RA patients. Subsequently, animal experiments showed that XFC significantly repressed immune inflammation, oxidative stress, synovial hyperplasia, and cartilage destruction, while improving the ultrastructure of synoviocytes in AA rats. XFC-containing serum diminished the proliferation of TNF-α-induced RA-FLSs, increased LINC00638 expression (P＜0.01), decreased interleukin-6 (IL-6), IL-17, reactive oxygen species (ROS) and reactive nitrogen species (RNS) levels (P＜0.01), and increased the protein expression of nuclear factor erythrocyte 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and superoxide dismutase 2 (SOD2) (P＜0.01). Furthermore, rescue experiments manifested that XFC-containing serum reversed the effects of silencing LINC00638 on inflammation and oxidative stress in RA-FLSs.

CONCLUSION

XFC inhibits inflammation and oxidative stress in RA by up-regulating LINC00638 and activating Nrf2/HO-1 pathway.

Gancao Fuzi decoction regulates the Th17/Treg cell imbalance in rheumatoid arthritis by targeting Foxp3 via miR-34a

ETHNOPHARMACOLOGICAL RELEVANCE

During the Eastern Han Dynasty, Zhang Zhongjing first recorded the Gancao Fuzi decoction (GCFZD) formula in the "Synopsis of the Golden Chamber", which is reportedly an effective and safe treatment for rheumatoid arthritis (RA). However, the mechanism underlying the observed improvement in the T helper 17 (Th17)/regulatory T (Treg) cell imbalance in RA obtained with GCFZD has not been reported.

AIM OF THE STUDY

This study aimed to demonstrate whether GCFZD ameliorated RA by modulating the Th17/Treg imbalance in RA mice.

MATERIALS AND METHODS

Collagen was used to induce a model of collagen-induced arthritis (CIA) in mice. GCFZD was administered by gavage, and the arthritis index score, imaging and histopathological changes of the ankle joints, and the levels of the immunoglobulin G (IgG) class antibodies and proinflammatory factors in serum were determined. In addition, the frequencies of Th17 and Treg cells, the levels of relevant transcription factors and functional factors and the miR-34a gene in the spleen and the levels of interleukin-17A (IL-17A) and IL-10 in serum were determined.

RESULTS

GCFZD significantly reduced the arthritis score, improved joint swelling and bone damage, reduced the pathological score, and decreased the serum levels of IgG class antibody (IgG and IgG2a) and proinflammatory factor [tumour necrosis factor-alpha (TNF-α), IL-1β and IL-6]. Moreover, the Th17-cell proportion, the expression level of the Th17-specific transcription factor retinoic acid-related orphan receptor γt (RORγt) and functional factor IL-17A in the spleen, and the serum IL-17A level were decreased, whereas the Treg cell proportion, expression levels of the Treg-specific transcription factor forkhead box P3 (Foxp3) and functional factor IL-10 in the spleen, and the serum IL-10 level were increased. Furthermore, GCFZD inhibited miR-34a gene expression while promoting Foxp3 protein expression.

CONCLUSIONS

The findings of this study demonstrate the therapeutic effect of GCFZD on mice with CIA, and the mechanism is related to an improvement in the Th17/Treg cell imbalance by targeting Foxp3 via miR-34a.

The role, targets and mechanisms of traditional Chinese medicine in regulating the balance of T helper type 17/regulatory Tcells in rheumatoid arthritis

Rheumatoid arthritis (RA) is a persistent systemic autoimmune disease, having all the hallmarks of joint swelling, joint tenderness, and progressive joint destruction, with synovitis and pannus formation as the basic pathological changes. T-lymphocyte infiltration is the key to its pathogenesis. During the growth of RA, the share of regulatory T (Treg) cells decreases, while the percentage of T helper type 17 (Th17) cells increases, giving rise to an imbalance of Th17/Treg cells. Modern medicine has made great advances in the treatment of RA and the selection of available drugs, but there are also the disadvantages of gastrointestinal reaction, high price, and low patient compliance. Therapy of RA remains a problem. Traditional Chinese medicine (TCM) has RA therapy developments, both in experimental research and clinical research, and its advantages of lasting effects and less detrimental reactions and fewer adverse effects are accepted by most patients. Numerous clinical and experimental studies have been performed in TCM on regulating Th17/Treg balance. However, the detailed mechanism of TCM intervention in Th17/Treg equilibrium in preventing and treating RA has not been discovered. In this article, the theory of regulating Th17/Treg cell equilibrium in RA is described from the perspectives of single Chinese medicine, active components of Chinese medicine, Chinese medicine compounds, and other therapies of TCM. It was found that TCM can regulate Th17/Treg cell balance and inhibit immunoreaction by intervening in cytokines, transcription factors, and signal pathways. It enables us to comprehensively and deeply understand the mechanism of TCM intervening in Th17/Treg balance in RA; provides direction for clinical therapy of RA; and offers new thoughts for understanding the pathogenesis of RA.

Effect of Er Miao San on peritoneal macrophage polarisation through the miRNA-33/NLRP3 signalling pathway in a rat model of adjuvant arthritis

CONTEXT

Er Miao San (EMS) is a formulation that contains Atractylodis Rhizoma and Phellodendri Cortex in 1:1 ratio, and is commonly used to treat rheumatoid arthritis (RA) and other inflammatory diseases.

OBJECTIVE

We investigated the mechanism of action and effects of EMS on peritoneal macrophage differentiation in a rat model of adjuvant arthritis (AA).

MATERIALS AND METHODS

EMS (3, 1.5 and 0.75 g/kg; once daily) and methotrexate (0.5 mg/kg; once every 3 days) were administered orally from days 21 to 35 after immunisation. Paw swelling and arthritis index were measured; pathological changes in the ankle joint were observed using x-ray and haematoxylin eosin staining. The ratio of CD86/CD206 in macrophages was detected by flow cytometry. Examination of the miRNA-33/NLRP3 signalling pathway was examined by RT-qPCR and western blotting. The levels of cytokines in the serum and cell supernatants were tested by ELISA.

RESULTS

EMS significantly reduced the AA index in rats (from 11.0 to 9.3) and pathological changes in the ankle joint (from 3.8 to 1.4). The ratio of CD86/CD206 was reduced, and polarisation to M1 improved (from 0.9 to 0.6) in macrophages of EMS-treated rats. EMS downregulated the miRNA-33/NLRP3 pathway. Furthermore, EMS treatment increased IL-10 and TGF-β levels in the serum and supernatant of macrophages of AA rats and simultaneously decreased the levels of IL-1β and TNF-α.

DISCUSSION AND CONCLUSIONS

Our results suggest that EMS may reduce macrophage polarisation to the M1 inflammatory phenotype by downregulating the miRNA-33/NLRP3 pathway in AA rats. These findings may provide new insights into the treatment of RA.

Elucidation of the anti-inflammatory mechanism of Er Miao San by integrative approach of network pharmacology and experimental verification

Traditional Chinese medicine (TCM) has been long time used in China and gains ever-increasing worldwide acceptance. Er Miao San (EMS), a TCM formula, has been extensively used to treat inflammatory diseases, while its bioactive components and therapeutic mechanisms remain unclear. In this study, we conducted an integrative approach of network pharmacology and experimental study to elucidate the underlying mechanisms of EMS in treating human rheumatoid arthritis (RA) and other inflammatory conditions. Quercetin, wogonin and rutaecarpine were probably the main active compounds of EMS in RA treatment as they affected the most RA-related targets, and TNF-α, IL-6 and IL-1β were considered to be the core target proteins. The main compounds in EMS bound to these core proteins, which was further confirmed by molecular docking and bio-layer interferometry (BLI) analysis. Moreover, the potential molecular mechanisms of EMS predicted from network pharmacology analysis, were validated in vivo and in vitro experiments. EMS was found to inhibit the production of NO, TNF-α and IL-6 in lipopolysaccharide (LPS)-stimulated RAW264.7 cells; reduce xylene-induced mouse ear edema; and decrease the incidence of carrageenan-induced rat paw edema. The carrageenan-induced up-regulation of TNF-α, IL-6 and IL-1β mRNA expression in rat paws was down-regulated by EMS, consistent with the network pharmacology results. This study provides evidence that EMS plays a critical role in anti-inflammation via suppressing inflammatory cytokines, indicating that EMS is a candidate herbal drug for further investigation in treating inflammatory and arthritic conditions.

Observation of the curative effect of Guizhi-Shaoyao-Zhimu decoction combined with methotrexate in the treatment of early rheumatoid arthritis based on ultrasonic evaluation: study protocol of a randomized, double-blind, controlled clinical trial

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease with the primary clinical symptoms of joint swelling and pain. Early detection of erosion and synovial inflammation at an active stage resulting from RA can prevent damage to the joints and activity restriction. However, there are still many patients who do not respond to these treatments; the development of newer, safer drugs is urgently needed. Compared to Western medicine, Guizhi-Shaoyao-Zhimu decoction has equal or higher efficacy and safety for RA patients. With the widespread use of musculoskeletal ultrasound (MSUS), this technology holds great value for the degree of joint damage in RA patients, guiding the clinical selection of treatments, and assessing of prognosis. Therefore, we designed a double-blinded randomized controlled clinical trial to measure the safety and efficacy of Guizhi-Shaoyao-Zhimu decoction in treating early-stage RA using MSUS.

METHODS

This study is a randomized, double-blinded, parallel group, placebo-controlled trial. A total of 152 adult participants with early RA will be enrolled, with balanced treatment allocation (1:1). The experimental intervention will be Guizhi-Shaoyao-Zhimu decoction plus the conventional medicine methotrexate and the control intervention will be placebo plus the conventional drug methotrexate for 3 months. In addition, both groups will receive folic acid during treatment to prevent side effects from methotrexate. The primary outcomes are the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), hepatic and renal function, visual analog scale, disease activity score in 28 joints, measurement scale for TCM symptoms, and 7-joint ultrasound score.

DISCUSSION

We designed this double-blinded randomized controlled clinical trial to evaluate the efficacy and safety of Guizhi-Shaoyao-Zhimu decoction in RA patients using MSUS. The results of this trial may provide insights into how to improve the clinical symptoms of RA patients and delay further joint destruction. We hope that this trial may provide preliminary evidence of the efficacy of Guizhi-Shaoyao-Zhimu decoction in treating RA patients and that these results aid researchers, practitioners, and patients alike.

AIM

The main aim of the study is to clarify the efficacy and safety of Guizhi-Shaoyao-Zhimu decoction in patients with early RA.

TRIAL REGISTRATION

Chinese Clinical Trials Register ChiCTR2000036141 . Registered on 21 August 2020 (retroactively registered).

Dysfunctions, Molecular Mechanisms, and Therapeutic Strategies of Regulatory T Cells in Rheumatoid Arthritis

Regulatory T cells (Tregs) represent a distinct subpopulation of CD4⁺ T lymphocytes that promote immune tolerance and maintain immune system homeostasis. The dysfunction of Tregs is tightly associated with rheumatoid arthritis (RA). Although the complex pathogenic processes of RA remain unclear, studies on Tregs in RA have achieved substantial progress not only in fundamental research but also in clinical application. This review discusses the current knowledge of the characterizations, functions, and molecular mechanisms of Tregs in the pathogenesis of RA, and potential therapies for these disorders are also involved.

Cedrol from Ginger Ameliorates Rheumatoid Arthritis via Reducing Inflammation and Selectively Inhibiting JAK3 Phosphorylation

Ginger, as a food spice, is widely applied due to its extensive effects. Cedrol (CE) found in ginger is a sesquiterpene with anti-inflammatory activity. The objective of this research is to discuss the efficacy of CE on ameliorating rheumatoid arthritis (RA). CE inhibited chronic inflammation and pain in a dose-dependent manner accompanied by rapid onset and long duration. Besides, CE treatment effectively ameliorated the paw edema volume and arthritis score with no significant effect on body weight. Organ index, T-cell and B-cell proliferation, histopathology, and immunohistochemistry demonstrated that CE had immunological enhancement and attenuated RA effects. Remarkably, inhibition of phosphorylated-JAK3 protein, thereby abating the secretion of pro-inflammatory cytokines and inflammation-related mediators, was involved in the potential mechanism of CE efficiency through forming a hydrogen bond with ARG953 and ILE955 in the JAK3 active pocket. At the same time, the pharmacokinetic results showed that the absolute bioavailability of CE at 20, 40, and 80 mg/kg was 30.30, 23.68, and 16.11%, respectively. The current results offered clues for mastering the ameliorated RA of CE and further perfected the effective substance basis on the anti-inflammatory effect of ginger, which was beneficial for further applications.

Shentong Zhuyu Decoction Inhibits Inflammatory Response, Migration, and Invasion and Promotes Apoptosis of Rheumatoid Arthritis Fibroblast-like Synoviocytes via the MAPK p38/PPARγ/CTGF Pathway

INTRODUCTION

The current study is aimed at exploring the effect of Shentong Zhuyu Decoction on the proliferation, migration, invasion, and apoptosis of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) and its underlying molecular mechanism.

MATERIALS AND METHODS

The type II collagen-induced arthritis (CIA) model was established. Subsequently, the RA-FLS were isolated from the CIA rat model and identified by immunohistochemistry. The viability, apoptosis, cell cycle, migration, and invasion of RA-FLS were detected by the cell counting kit 8 (CCK-8) assay, flow cytometry, wound-healing assay, and transwell invasion assay, respectively. The levels of MAPK p38, PPARγ, CTGF, Bcl-2, Bax, caspase-3, IL-1β, MMP-3, CDK4, and cyclin D1 were determined by qRT-PCR and western blotting, respectively.

RESULTS

After treatment with Shentong Zhuyu Decoction medicated serum, the OD570 value, migrative and invasive abilities, and the secretion of IL-1β, MMP-3 were remarkably decreased in RA-FLS, while the apoptosis rate was increased. Further, results showed that Shentong Zhuyu Decoction inhibited the transition from the G1 phase to S phase. Additionally, Shentong Zhuyu Decoction significantly inhibited the expression of Bcl-2, CDK4, cyclin D1, MAPK p-p38, and CTGF, whereas elevated the levels of Bax, caspase-3, and PPARγ. Importantly, the effects of Shentong Zhuyu Decoction were consistent with the trends of MAPK P38 inhibitor (SB203580) and PPARγ agonist (GW1929).

CONCLUSIONS

Shentong Zhuyu Decoction inhibited viability, inflammatory response, migration, invasion, and transition from the G1 phase to S phase and promoted apoptosis of RA-FLS via the MAPK p38/PPARγ/CTGF pathway.

Chemical Composition of Pterospermum heterophyllum Root and its Anti-Arthritis Effect on Adjuvant-Induced Arthritis in Rats via Modulation of Inflammatory Responses

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease without effective and beneficial drugs. Many traditional folk medicines have been proven to be effective in treating RA. Among these, the root of Pterospermum heterophyllum Hance has been widely used as a traditional remedy against RA in China, but there is no scientific basis yet. The aim of this study was to investigate for the first time the chemical compositions and therapeutic effect of P. heterophyllum on adjuvant-induced arthritis (AIA) model in rats. 73 compounds were identified from P. heterophyllum based on ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-qTOF-MS/MS), and flavonoids may be partly responsible for the major anti-arthritic effect. In parallel, the P. heterophyllum extract at 160, 320, and 640 mg/kg/day were orally administered to rats for 22 days after post-administration adjuvant. The results showed that P. heterophyllum remarkably ameliorated histological lesions of the knee joint, increased body weight growth, decreased arthritis score, reduced thymus and spleen indices in model rats. Moreover, P. heterophyllum treatment persuasively downregulated the levels of rheumatoid factor (RF), C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), IL-6, IL-17, cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX) and matrix metalloproteinase-2 (MMP-2), and observably upregulated IL-4 and IL-10 levels in model rats. These findings suggest that P. heterophyllum has a prominent anti-RA effect on AIA rats by modulating the inflammatory responses, and supports the traditional folk use of this plant.

The Protective Effects of the Ethyl Acetate Part of Er MiaoSan on Adjuvant Arthritis Rats by Regulating the Function of Bone Marrow-Derived Dendritic Cells

Aims

The aim of this study was to evaluate the protective effects of Er Miao San (EMS) and the regulative function of bone marrow-derived dendritic cells (BMDCs) on adjuvant arthritis (AA) in rats.

Methods

The ethyl acetate part of EMS (3 g/kg, 1.5 g/kg, and 0.75 g/kg) was orally administered from day 15 after immunization to day 29. The polyarthritis index and paw swelling were measured, the ankle joint pathological changes were observed using hematoxylin-eosin (HE) staining, and the spleen and thymus index were determined. Moreover, T and B cell proliferation were determined using the CCK-8 assay. The expression of BMDC surface costimulatory molecules and inflammatory factors were determined using flow cytometry and ELISA kits, respectively.

Results

Compared with the AA model rats, the ethyl acetate fraction of EMS obviously reduced paw swelling (from 1.0 to 0.7) and the polyarthritis index (from 12 to 9) (P < 0.01) and improved the severity of histopathology (P < 0.01). The treatment using ethyl acetate fraction of EMS significantly reduced the spleen and thymus index (P < 0.01) and inhibited T and B cell proliferation (P < 0.01). Moreover, EMS significantly modulated the expression of surface costimulatory molecules in BMDCs, including CD40, CD80, CD86, and major histocompatibility complex class II (MHC-II) (P < 0.01). The results also showed that the ethyl acetate part of EMS significant inhibited the levels of proinflammatory cytokines interleukin- (IL-) 23 tumor necrosis factor- (TNF-) α and inflammatory factor prostaglandin (PG) E2 in the supernatant of BMDCs. However, the level of anti-inflammatory cytokine IL-10 was significantly increased (P < 0.01).

Conclusion

These results suggest that the ethyl acetate part of EMS has better protective effects on AA rats, probably by regulating the function of BMDCs and modulating the balance of cytokines.