Investigation of the effect of phlomisoside F on complete Freund's adjuvant-induced arthritis

Triterpenes G-A and G-E from Galphimia glauca with anti-inflammatory and anti-arthritic activity in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Galphimia glauca is a medicinal plant that treats inflammatory and anti-rheumatic problems. Its anti-inflammatory capacity has been reported pharmacologically, attributed to the triterpenes G-A and G-E.

AIM

The objective of the present work was to measure the anti-inflammatory and immunomodulatory effect of the methanolic extract (GgMeOH) of Galphimia glauca and the isolated galphimines G-A and G-E, first in an acute test of plantar edema with carrageenan, and later in the model of experimental-induced arthritis with CFA. The effect was measured by quantifying joint inflammation, the concentration of pro- (TNF-α, IL-6, IL-17) and anti-inflammatory (IL-10, and IL-4) cytokines, and the ADA enzyme in joints, kidneys, and spleen from mice with experimental arthritis.

METHOD

The extract and the active triterpenes were obtained according to established methods using different chromatographic techniques. Female ICR strain mice were subjected to intraplantar administration with carrageenan and treated with different doses of GgMeOH, G-A, and G-E; edema was monitored at different times. Subsequently, the concentration of TNF-a and IL-10 in the spleen and swollen paw was quantified. Meloxicam (MEL) was used as an anti-inflammatory control drug. The most effective doses of each treatment were analyzed using a complete Freunds adjuvant (CFA)-induced experimental arthritis model. Joint inflammation was followed throughout the experiment. Ultimately, the concentration of inflammation markers, oxidant stress, and ADA activity was quantified. In this experimental stage, methotrexate (MTX) was used as an antiarthritic drug.

RESULTS

Treatments derived from G. glauca, GgMeOH (DE50 = 158 mg/kg), G-A (DE50 = 2 mg/kg), and G-E (DE50 = 1.5 mg/kg) caused an anti-inflammatory effect in the plantar edema test with carrageenan. In the CFA model, joint inflammation decreased with all natural treatments; GgMeOH and G-A inhibited the ADA enzyme in all organs analyzed (joints, serum, spleen, left and right kidneys), while G-E inhibited the enzyme in joints, serum, and left kidney. CFA caused an increase in the weight index of the organs, an effect that was counteracted by the administration of G. glauca treatments, which also modulate the response to the cytokines analyzed in the different organs (IL-4, IL-10, IL-17, IL-6, and TNF- α).

CONCLUSION

It is shown, for the first time, that the GgMeOH extract and the triterpenes G-A and G-E of Galphimia glauca have an anti-arthritic effect (anti-inflammatory, immunomodulatory, antioxidant, and ADA inhibitor), using an experimental arthritis model with CFA. Therefore, knowledge of the plant as a possible therapeutic agent for this rheumatic condition is expanding.

Silibinin's Effects against Methotrexate-Induced Hepatotoxicity in Adjuvant-Induced Arthritis Rat Model

Methotrexate (MTX) is the first drug of choice to treat several diseases, including rheumatoid arthritis. However, its administration is accompanied by severe side effects, most commonly hepatotoxicity. Hence, alternative therapies with a lower toxicity and fewer side effects are needed. This study aimed to investigate the antioxidant and hepatoprotective effects of silibinin (SIL, natural agent) against MTX-induced hepatotoxicity in an adjuvant-induced arthritis (AIA) rat model. Arthritic rats were treated with SIL (100 mg/kg) and/or methotrexate (2 mg/kg). Non-arthritic rats, arthritic untreated rats, and arthritic rats who received the vehicle were followed in parallel. SIL alleviated the systemic consequences of arthritis by restoring lost weight, decreasing the erythrocyte sedimentation rate, and ameliorating joint damage, which was evident both micro- and macroscopically. Additionally, SIL prevented the histopathological alterations in the liver and significantly reduced the liver damage caused by MTX and AIA, as shown by a decrease in the markers of liver damage (ALT and AST). Furthermore, SIL relieved the oxidative stress induced by AIA and MTX in liver tissue by decreasing the lipid peroxidation (MDA) levels and enhancing the antioxidant defense system (GSH levels; catalase and superoxide dismutase (SOD) activities). In conclusion, our results suggest that SIL is a potent antioxidant and hepatoprotective agent in arthritic rats. It markedly attenuated the progression and severity of the arthritic disease and eased the oxidative stress in liver tissue by improving the pro-oxidant/antioxidant balance.

Clinical Evaluation of Collagen-Induced Arthritis in Female Lewis Rats: A Comprehensive Analysis of Disease Progression and Severity

OBJECTIVE

The collagen-induced arthritis (CIA) model is the most commonly studied autoimmune model of rheumatoid arthritis (RA). In this study, we investigated the usefulness of collagen type II emulsified in Freund's incomplete adjuvant (CII/IFA) as a suitable method for establishing RA in Lewis rats. The aim of the present study was to present a straightforward and effective method for inducing CIA in rats.

MATERIALS AND METHODS

In this experimental study, animals were divided into two equal groups (n=5); control and CIA. Five rats were injected intradermally at the base of the tail with a 0.2 ml CII/IFA emulsion. On the seventh day, a 0.1 ml CII/IFA emulsion booster was injected. Arthritis symptoms that arose were evaluated at clinical, histological, radiological, and at protein expression levels to find out if the disease had been induced successfully.

RESULTS

Our finding showed a decreasing trend in the body weight during the RA induction period, while the arthritis score and paw thickness were increased during this period. The results of the enzyme-linked immunosorbent assay (ELISA) for serum samples revealed that the levels of proinflammatory cytokines, interleukin (IL)-1β, IL-6, IL-17, and tumor necrosis factor (TNF)-α and anti-CII IgG were significantly increased in CIA rats compared to the control group. After CIA induction, the level of anti-inflammatory protein IL-10 was decreased significantly. Radiographic examination of the hind paws showed soft tissue swelling, bone erosion, and osteophyte formation in CIA rats. Additionally, based on histological evaluations, the hind paws of the CIA group showed pannus formation, synovial hyperplasia, and bone and cartilage destruction.

CONCLUSION

It seems that CII/IFA treatment can be an appropriate and effective method to induce RA disease in Lewis rats. This well-established and well-characterized CIA model in female Lewis rats could be considered to study aspects of RA and develop novel anti-arthritic agents.

In vitro-in vivo assessments of apocynin-hybrid nanoparticle-based gel as an effective nanophytomedicine for treatment of rheumatoid arthritis

Apocynin (APO), a well-known bioactive plant-based phenolic phytochemical with renowned anti-inflammatory and antioxidant pharmacological activities, has recently emerged as a specific nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidase inhibitor. As far as we know, no information has been issued yet regarding its topical application as a nanostructured-based delivery system. Herein, APO-loaded Compritol® 888 ATO (lipid)/chitosan (polymer) hybrid nanoparticles (APO-loaded CPT/CS hybrid NPs) were successfully developed, characterized, and optimized, adopting a fully randomized design (32) with two independent active parameters (IAPs), namely, CPT amount (XA) and Pluronic® F-68 (PF-68) concentration (XB), at three levels. Further in vitro-ex vivo investigation of the optimized formulation was performed before its incorporation into a gel base matrix to prolong its residence time with consequent therapeutic efficacy enhancement. Subsequently, scrupulous ex vivo-in vivo evaluations of APO-hybrid NPs-based gel (containing the optimized formulation) to scout out its momentous activity as a topical nanostructured system for beneficial remedy of rheumatoid arthritis (RA) were performed. Imperatively, the results support an anticipated effectual therapeutic activity of the APO-hybrid NPs-based gel formulation against Complete Freund's Adjuvant-induced rheumatoid arthritis (CFA-induced RA) in rats. In conclusion, APO-hybrid NPs-based gel could be considered a promising topical nanostructured system to break new ground for phytopharmaceutical medical involvement in inflammatory-dependent ailments.

Macrophage Polarization Towards M2 Phenotype by Curcuminoids Through NF-κB Pathway Inhibition in Adjuvant-Induced Arthritis

Macrophage polarization is decisive for homeostasis maintenance and tissue repair. Anti-inflammatory properties of curcumin (CUR) have been demonstrated in several studies. It used in the treatment of bone disorders includingrheumatoid arthritis. The present study aims to explore the potential mechanisms of curcumin on macrophage polarization, expression, activation, and cytokine secretion in adjuvant-induced arthritis as well as its possible role in enhancing the therapeutic action of methotrexate (MTX) together with minimizing MTX initiated side-effects. Rats were divided into eight groups as follows; Control group, MTX group: was weekly injected with MTX, CUR group: was treated with a daily oral dose of curcumin, MTX + CUR group: was treated with both methotrexate and curcumin, Adjuvant arthritis group (AIA): was injected with complete Freund's adjuvant for arthritis induction, AIA/MTX group: arthritic rats treated with methotrexate, AIA/CUR group: arthritic rats treated with curcumin and AIA/MTX + CUR: arthritic rats treated with both methotrexate and curcumin. Paw swelling, haematological analysis, immunological studies, histological observations and quantitative immunohistochemical investigations were performed. The present results showed that treating arthritic rats with curcumin either alone or in combination with methotrexate resulted in amelioration in paws inflammation, growth rate, absolute and relative spleen weights, and haematological analyses. Antinuclear antibodies, IL-1β, IL-8, IL-10, NF-kB levels, and CD68 + joint expression were also ameliorated. The microscopic examination of joint and spleen showed more improvement as apparently normal tissues in treated groups. It can be concluded that curcumin seems to be most promising in regulating macrophage expression, activation, cytokine secretion, and polarization, thus providing a novel insight in the application of curcumin-based treatments.

Bioactive fraction of Tragia involucrata Linn leaves attenuates inflammation in Freund's complete adjuvant-induced arthritis in Wistar albino rats via inhibiting NF-κB

Tragia involucrata Linn. (T. involucrata) belongs to the family of Euphorbiaceae found in the subtropical regions. Traditionally, the plant parts are used to treat inflammation, wounds and skin infection by people of the Western Ghats, India. Few studies on the acute anti-inflammatory activity of T. involucrata extracts were reported earlier. The present study aims to identify the bioactive fraction of T. involucrata and to evaluate its mechanism in Complete Freund's Adjuvant-induced arthritic rat model. The leaf extract was highly effective among the methanolic leaf and root extracts. The hexane (HF) and a methanolic fraction (MF) of the leaf extract of T involucrata were further identified as a bioactive fraction evaluated through protein denaturation assay. The HF and MF were further studied for their anti-inflammatory potential in a chronic inflammatory model, and their mechanism of action was explored further. Arthritis was induced by administering 0.1 ml of CFA intradermally. The treatment was started the next day with HF (100 and 250 mg/kg/day) and MF (100 and 250 mg/kg/day), while the HF and MF alone group served as the drug control, Indomethacin-treated group served as the positive control. On the 25th day, the animals were euthanized, and their body weight, paw thickness, arthritic score, spleen and thymus weight, haematological parameters, biochemical parameters, radiographs and histopathology were analyzed. Results showed that the MF-treated animals maintained dry weight, reduced paw thickness, arthritic scores, and haematological and biological parameters compared to the HF-treated and CFA-induced arthritic rats. Both radiological and histopathological analyses of the joints revealed that the MF-treated groups restored bone architecture without any erosion and normal tissue architecture with nil signs of active inflammation. Western blot analysis revealed that MF has effectively inhibited the protein expression levels of MMP-3, MMP-9, and NF-κB in the synovial tissues compared to that of CFA-induced arthritic rats. Besides, HPLC analysis revealed the presence of flavonoids, including gallic acid, rutin and Quercetin, in the MF of T. involucrata, which had shown to have potent anti-inflammatory potential. Thus, it can be emphasized that T. involucrata could be a potential therapeutic candidate for treating inflammatory diseases, which needs further experimental studies to confirm its safety and efficacy.

Inflammation Modulating Activity of the Hydroethanol Stem Bark Extract of Bombax costatum in Murine Models

Bombax costatum (Bombacaceae) is traditionally used as a decoction of the leaves, stem, and root to treat headaches, fever, and oedema that may be associated with inflammatory conditions. Thus, the aim of this study was to evaluate the effect of 70%^v/_v ethanolic extract of the stem bark of Bombax costatum on acute and chronic inflammation. The effect of Bombax costatum extract (10, 50, 100 mg kg^-1, p.o) was studied in prostaglandin E₂-induced paw oedema in Sprague-Dawley rats (n = 5). Subsequently, the effect of the extract on clonidine and haloperidol-induced catalepsy was also investigated in ICR mice (n = 5). Finally, the ability of the extract to inhibit chronic inflammation was studied using a rat adjuvant-induced arthritis model. Pre-emptive and therapeutic administration of the extract at all doses significantly suppressed the formation of oedema following prostaglandin E ₂ administration. As a measure of indirect antihistaminic effect, treatment with the extract suppressed clonidine-induced catalepsy but not haloperidol-induced catalepsy. Moreover, Bombax costatum extract significantly inhibited joint inflammation and damage following injection of complete Freund's adjuvant. Treatment with the extract also inhibited the onset of polyarthritis; thus, suppressing the systemic spread of joint inflammation from ipsilateral limbs to contralateral limbs. In conclusion, the hydroethanol extract of the stem bark of Bombax costatum inhibits both acute and chronic inflammation.

Activities and Molecular Mechanisms of Diterpenes, Diterpenoids, and Their Derivatives in Rheumatoid Arthritis

Diterpenes and their derivatives have many biological activities, including anti-inflammatory and immunomodulatory effects. To date, several diterpenes, diterpenoids, and their laboratory-derived products have been demonstrated for antiarthritic activities. This study summarizes the literature about diterpenes and their derivatives acting against rheumatoid arthritis (RA) depending on the database reports until 31 August 2021. For this, we have conducted an extensive search in databases such as PubMed, Science Direct, Google Scholar, and Clinicaltrials.gov using specific relevant keywords. The search yielded 2708 published records, among which 48 have been included in this study. The findings offer several potential diterpenes and their derivatives as anti-RA in various test models. Among the diterpenes and their derivatives, andrographolide, triptolide, and tanshinone IIA have been found to exhibit anti-RA activity through diverse pathways. In addition, some important derivatives of triptolide and tanshinone IIA have also been shown to have anti-RA effects. Overall, findings suggest that these substances could reduce arthritis score, downregulate oxidative, proinflammatory, and inflammatory biomarkers, modulate various arthritis pathways, and improve joint destruction and clinical arthritic conditions, signs, symptoms, and physical functions in humans and numerous experimental animals, mainly through cytokine and chemokine as well as several physiological protein interaction pathways. Taken all together, diterpenes, diterpenoids, and their derivatives may be promising tools for RA management.

Effects of different doses of complete Freund's adjuvant on nociceptive behaviour and inflammatory parameters in polyarthritic rat model mimicking rheumatoid arthritis

Complete Freund's adjuvant (CFA) has been used to develop the arthritic or inflammatory condition in the animal, but there is a lack of information concerning high CFA doses on nociceptive behaviour and inflammatory parameters. This study aimed to compare the effects of different high doses of CFA in rat to closely mimic nociceptive and inflammatory parameters of rheumatoid arthritis (RA) in humans. Twenty-four male Sprague-Dawley rats were randomly divided into four groups (n = 6): Control (C), CFA-induced polyarthritic groups at 5.0 mg/mL (CFA 5.0), 7.5 mg/mL (CFA 7.5) and 10.0mg/mL (CFA 10.0). The rats' right hindpaw was inoculated with CFA intradermally and developed into a polyarthritic state within 20 days. Nociceptive behavioural assessments, including von Frey and hot plate tests and spontaneous activities, were conducted on day 0, 7, 15 and 20. Bilateral ankle joints diameter and circumference, full blood count, joints and paw histological examinations were also conducted throughout the study period. Based on the results, CFA 5.0 and CFA 7.5 groups showed a significant increase in spontaneous activities and development of thermal hyperalgesia but no change in body weight and food intake, no development of tactile allodynia and haematological indices, and no significant morphological changes of joints histology. Meanwhile, CFA 10.0 group demonstrated significant and constant changes in all nociceptive and inflammatory parameters investigated. In conclusion, CFA at the dose of 10mg/mL has the most potential and reliable dosage to develop polyarthritis in a rat model to mimic RA condition in humans.

Molecular toxicity of methotrexate in rheumatoid arthritis treatment: A novel perspective and therapeutic implications

Rheumatoid arthritis (RA) is an autoimmune inflammatory systematic complication which is a chronic disorder that severely affects bones and joints and results in the quality of life impairment. Methotrexate (MTX), an FDA-approved drug has maintained the standard of care for treating patients affected with RA. The mechanism of MTX includes the inhibition of purine and pyrimidine synthesis, suppression of polyamine accumulation, promotion of adenosine release, adhesion of the inflammatory molecules, and controlling of cytokine cascade in RA. The recommended dose for RA patients is 5-25 mg of MTX per week, depending on the severity of the disease but MTX has proven to be cytotoxic with side effects affecting various tissues when treating RA patients even with low doses over a prolonged period of time. The mechanism of such toxicity is not entirely understood. This review strives to understand it by correlating the different pathways, including MTX in folate metabolism, Sirt1/Nrf2/γ-gcs, and γ-gcs/CaSR-TNF-α/NF-kB signaling. In addition to this, the importance of targeted therapy combination with MTX on RA treatment and combinations approved from the clinical trials are also briefly discussed. Overall, this review elucidates the various MTX molecular mechanisms and toxicity at the molecular level, the limitations, and the scope for future directions.

Anti-arthritic activity of Ricinus communis L. and Withania somnifera L. extracts in adjuvant-induced arthritic rats via modulating inflammatory mediators and subsiding oxidative stress

OBJECTIVES

This study aimed to evaluate the anti-arthritic activity of Ricinus communis leaves' and Withania somnifera roots' hydroalcoholic extracts in Complete Freund's adjuvant-induced arthritis in Wistar rats.

MATERIALS AND METHODS

HPLC and FT-IR analysis detected pharmacologically important phytocompounds in both plant extracts. Oral treatments including methotrexate (MTX; 3 mg/kg twice a week) and extracts at 250 and 500 mg/kg/day were initiated after arthritis induction. Changes in paw swelling, arthritic score, body weight, organ indices (thymus and spleen), hematological and biochemical parameters, and pro-/anti-inflammatory cytokine expression using qRT-PCR were assessed. Oxidative stress markers in hepatic tissue were determined. Histopathological and radiological examinations were also performed.

RESULTS

RCE (R. communis extract) and WSE (W. somnifera extract) demonstrated a reduction in paw swelling, arthritic score, and restoration of body weight and organ indices. Hematological parameters, serum inflammatory markers such as CRP and RF, and liver function markers of arthritic rats were significantly (P<0.01) ameliorated with RCE and WSE treatment. Both plants persuasively down-regulated IL-1β, IL-6, IL-17a, TNF-α, and RANKL and up-regulated IL-4, INF-γ, and OPG relative expression as well as alleviating hepatic oxidative stress parameters. Histopathological and radiological findings revealed a marked reduction in tissue inflammation and bone erosion in extracts treated groups.

CONCLUSION

The study findings suggest that R. communis leaves and W. somnifera roots have markedly subsided inflammation and improved health through modulating pro-/anti-inflammatory cytokine expression and reducing oxidative stress.

Activation of the Nrf2/HO-1 signaling pathway by dimethyl fumarate ameliorates complete Freund's adjuvant-induced arthritis in rats

The nuclear factor erythroid 2-related factor (Nrf2) signaling pathway has recently emerged as a novel therapeutic target in treating various diseases. Therefore, the present study aimed to assess the protective role of the Nrf2 activator, dimethyl fumarate (DMF) in the complete Freund's adjuvant (CFA)- induced arthritis model. DMF (25, 50, and 100 mg/kg) and dexamethasone (2 mg/kg) were orally administered for 14 days. Pain-related tests, paw volume, and arthritic scores were measured weekly. Serum TNF-α, IL-1β, cyclic citrullinated peptide (CCP), C-reactive protein (CRP), and rheumatoid factor (RF) levels were estimated. Nitrite, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione (GSH), catalase (CAT), and myeloperoxidase (MPO) levels were also evaluated. NF-κB, Nrf2, HO-1, and COX-2 levels were estimated in the joint tissue. DMF treatment exerted anti-arthritic activity by enhancing the nociceptive threshold, improving arthritis scores, and reducing paw edema. Also, DMF suppressed changes in oxidative stress markers and inflammatory mediators and enhanced Nrf2 and HO-1 levels in CFA-injected rats. These findings indicate that the anti-arthritic activity of DMF may be mediated by the activation of the Nrf2/HO-1 pathway, which reduced oxidative damage and inflammation.

Appraisal of the Antiarthritic Potential of Prazosin via Inhibition of Proinflammatory Cytokine TNF-α: A Key Player in Rheumatoid Arthritis

Prazosin, a selective α₁ adrenergic receptor antagonist, with documented anti-inflammatory potential, was evaluated for its antiarthritic efficacy by targeting specifically TNF-α. The antiarthritic attribute of prazosin validated through in vitro screening comprised thermally provoked denaturation of bovine serum albumin (BSA) and egg albumin along with membrane stabilization evaluation at a concentration of 100-6400 μg/mL, while in vivo screening comprised formaldehyde-instigated arthritis at the doses of 5, 10, and 20 mg/kg and complete Freund's adjuvant (CFA)-induced arthritis at 20 mg/kg dose. Paw swelling, body weight, arthritic score, hematological parameters, and histological and radiographic examination of ankle joints were assessed for a period of 28 days after CFA immunization. Moreover, the proinflammatory cytokine TNF-α level was also assessed through quantitative real-time polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Prazosin revealed significant antiarthritic effect evident through protein denaturation inhibition in the egg albumin and the BSA model, stabilization of red blood cell membrane in the membrane stabilizing assay, and reduction in paw volume in formaldehyde-induced arthritis. Likewise, prazosin exhibited propitious antiarthritic effects in the CFA-provoked arthritis model manifested by paw volume and arthritic score alleviation, substantial weight loss prevention, and preservation of the normal hematological and biochemical profile. Histological and X-ray investigation unveiled no substantive structural alterations in treated rat's ankle joints. The TNF-α expression level was also reduced. Thus, the current study is suggestive that prazosin exhibits a strong antiarthritic potential possibly through inhibition of TNF-α.

Amelioration of oxidative and inflammatory changes by Peganum harmala seeds in experimental arthritis

Background

The present study was designed to investigate the therapeutic effects against oxidative stress and alleviative effects of Peganum harmala seeds (PH) in rats with Complete Freund’s Adjuvant (CFA) induced arthritis.

Methods

The extract was evaluated for its phytoconstituents, antiarthritic and antioxidant properties. The action of chloroform (PHC) and ethanolic (PHE) extracts of PH was evaluated in adult Lewis rats (150-200 g).with CFA induced arthritis. Arthritic rats received PH extracts 100 mg/kg orally for 28 consecutive days (Prophylactic treatment) and from 14th day of CFA injection (Therapeutic treatment).

Results

PHE significantly suppressed the arthritis severity in rats than PHC in 28 days. All complications shown significant reduction (p< 0.05) in arthritic rats including paw volume (63.09%), body weight loss, decreased locomotor activity, erythrocyte sedimentation rate and synovial/hepatic tissues lipid peroxidation and increase in cellular antioxidants superoxide dismutase (U/mg) activities and hemoglobin counts. The results showed the presence of alkaloids and flavonoids in PHE. Histology and radiographic analysis of arthritic ankle joints indicated abnormal changes. Marked reduction in inflammation and arthritic changes were observed after treatment with PHE.

Conclusion

Therefore, the investigation suggests that PHE at 100 mg/kg will be useful in the management of rheumatoid arthritis complications which may possibly be due to boosting the intracellular antioxidant defense.

Antiarthritic Potential of Calotropis procera Leaf Fractions in FCA-Induced Arthritic Rats: Involvement of Cellular Inflammatory Mediators and Other Biomarkers

Calotropis procera (commonly known as Swallow wort) is described in the Ayurvedic literature for the treatment of inflammation and arthritic disorders. Therefore, in the present work, the antiarthritic activity of potential fractions of Swallow wort leaf was evaluated and compared with standards (indomethacin and ibuprofen). This study was designed in Wistar rats for the investigation of antiarthritic activity and acute toxicity of Swallow wort. Arthritis was induced in Wistar rats by injecting 0.1 mL of Freund’s complete adjuvant (FCA) on the 1st and 7th days subcutaneously into the subplantar region of the left hind paw. Evaluation of our experimental findings suggested that antiarthritic activity of methanol fraction of Swallow wort (MFCP) was greater than ethyl acetate fraction of Swallow wort (EAFCP), equal to standard ibuprofen, and slightly lower than standard indomethacin. MFCP significantly reduced paw edema on the 17th, 21st, 24th, and 28th days. It also showed significant effect (p < 0.01) on arthritic score, paw withdrawal latency, and body weight. The inhibition of serum lysosomal enzymes and proinflammatory cytokines along with improvement of radiographic features of hind legs was also recorded with MFCP. Finally, it was concluded that MFCP can be a feasible therapeutic candidate for the treatment of inflammatory arthritis.

Anti-arthritic activity of D-carvone against complete Freund's adjuvant-induced arthritis in rats through modulation of inflammatory cytokines

Chronic joint pain due to loss of cartilage function, degradation of subchondral bone, and related conditions are common plights of an arthritis patient. Antioxidant compounds could solve the problems in arthritic condition. The objective of this study was to evaluate the anti-arthritic activity of D-carvone against complete Freund's adjuvant (CFA)-induced arthritis in rats. D-carvone was orally administered for 25 days at the doses of 30 and 60 mg/kg against CFA-induced arthritic rats. Changes in body weight, paw swelling, organ index, hematological parameters, oxidative stress markers, inflammatory cytokines, and histopathology were recorded. Oral treatment of D-carvone significantly improved the body weight, reduced the paw swelling, edema formation, and organ index in arthritic rats. The levels of white blood cells were reduced, red blood cells and hemoglobin levels were improved in D-carvone treated arthritic rats. Lipid peroxidation levels were lowered whereas enzymatic and non-enzymatic antioxidants were significantly elevated by D-carvone administration against arthritic rats. D-carvone significantly modulated inflammatory cytokine levels and improved the ankle joint pathology against CFA-induced arthritic inflammation. In conclusion, D-carvone proved significant anti-arthritic activity against CFA-induced arthritis in rats.

Exploring the Effect of Terminalia catappa Fruit Extract in Rheumatoid Arthritis: An Evaluation of Behavioural, Hematologiocal and Histopathological Parameters

BACKGROUND AND OBJECTIVE

Rheumatoid Arthritis (RA) is an autoimmune disease characterized by failure of spontaneous resolution of inflammation with lifetime perseverance, becoming principal cause of inactivity. Many conventional therapies are in use but the side effects associated with them are equally problematic. Therefore, an urge to explore advanced therapeutic approaches with least adverse events has seeded the idea of discovering newer herbal drugs and their respective constituents in management of RA. The current research explores anti-arthritic activity of Terminalia catappa fruits hydroalcoholic extract in CFA induced Wistar rats.

METHODS

The fruits were obtained, washed, dried and processed to obtain hydroalcoholic powdered extract which was dissolved in water and given orally to the rats. Wistar rats of either sex were used in the study. The animals were injected with 0.1 ml of complete freund's adjuvant (CFA) in footpad of left hind paw. The treatment was initiated from day 0 by oral dosing of Terminalia catappa fruit extract in doses of 40 mg/kg and 80 mg/kg followed by CFA administration to day 21 and behavioral, hematological parameters besides histopathological screening were assessed simultaneously.

RESULTS

The arthritic symptoms were observed to gradually decrease in treatment groups when compared against disease control groups. The parameters like body weight and pain latency were increased whereas paw volume and arthritic score were found to significantly decrease in treatment groups as compared to disease control group. The hematological parameters were also modified and were studied in treatment groups. The histopathological estimation depicted extent of damage in joint tissue of diseased rat comparable to normal, standard and combination therapy group.

CONCLUSION

The fruits possess anti-arthritic properties and significantly reduced paw volume, arthritic score and increased pain threshold and body weight gain besides theory hematological effects like increase in Hb and RBC and decrease in WBC, platelets and ESR levels simultaneously. The histopathological estimation confirmed decreased deterioration of joint tissue in treatment groups as compared to disease control group hence proving to be an emerging therapeutic option in management of RA.

Polystichum braunii extracts inhibit Complete Freund's adjuvant-induced arthritis via upregulation of I-κB, IL-4, and IL-10, downregulation of COX-2, PGE2, IL-1β, IL-6, NF-κB, and TNF-α, and subsiding oxidative stress

Polystichum braunii (Spenn.) Fée is a traditional remedy for rheumatoid arthritis, a chronic inflammatory disorder of polygenetic origin. The current project was intended to demonstrate the role of inflammatory and oxidative stress biomarkers in the anti-arthritic activity of the P. braunii extracts. Methanolic and aqueous extracts of the plant roots were prepared by triple maceration. The phytochemical evaluation of the plant extracts was carried out by high-performance liquid chromatography (HPLC). The plant extracts at 150, 300, and 600 mg/kg/day and piroxicam (10 mg/kg/day) were orally administered to Wistar rats for 21 days that were previously immunized with Complete Freund's adjuvant (150 µl on right hind paw) except normal and arthritic control rats. Both plant extracts mitigated the paw oedema, restored the immune organ and body weights, and ameliorated the level of blood parameters such as haemoglobin, red blood cells, platelets, white blood cells, alkaline phosphatase (ALP), C-reactive proteins, and rheumatoid factor. The evaluation of gene expression using quantitative-real-time polymerase chain reaction (qRT-PCR) revealed the substantial downregulation of tumor necrosis factor (TNF)-α, Interleukin (IL)-6, IL-1β, cyclo-oxygenase (COX)-2, nuclear factor (NF)-κB, and upregulation of IL-4, IL-10 and I-κB in polyarthritic rats treated with the plant extracts. Methanolic plant extract exhibited the maximum effect on upregulation of IL-4 (79 ± 3%), IL-10 (62.66 ± 4.93%), and I-κB (73.66 ± 3.05%) at 600 mg/kg/day. Treatment with the plant extracts also reduced the level of prostaglandin E2 and TNF-α in the serum of arthritic rats' dose dependently. It was also found that the plant extracts and piroxicam increased (p < 0.05) the activities of superoxide dismutase and catalase in the liver tissue while reduced the level of malondialdehyde in arthritic rats. Histological examination of ankle joints revealed that the plant extracts decreased the pannus formation, inflammation, and synovial hyperplasia in arthritic animals. HPLC analysis depicted that the plant extracts had contained kaempferol, quercetin, gallic acid, and other phenolic acids. It can be elucidated from the results that the extracts of P. braunii roots exhibited anti-arthritic activity in Wistar rats through modulation of inflammatory cytokines and boosting the antioxidant defense mechanism.

Comparison of the acute toxicity, analgesic and anti-inflammatory activities and chemical composition changes in Rhizoma anemones Raddeanae caused by vinegar processing

Background

As the dry rhizome of Anemone raddeana Regel, Rhizoma Anemones Raddeanae (RAR), which belongs to Ranunculaceae, is usually used to treat wind and cold symptoms, hand-foot disease and spasms, joint pain and ulcer pain in China. It is well known that the efficacy of RAR can be distinctly enhanced by processing with vinegar due to the reduced toxicity and side effects. However, the entry of vinegar into liver channels can cause a series of problems. In this paper, the differences in the acute toxicity, anti-inflammatory and analgesic effects between RAR and vinegar-processed RAR were compared in detail. The changes in the chemical compositions between RAR and vinegar-processed RAR were investigated, and the mechanism of vinegar processing was also explored.

Methods

Acute toxicity experiments were used to examine the toxicity of vinegar-processed RAR. A series of studies, such as the writhing reaction, ear swelling experiment, complete Freund’s adjuvant-induced rat foot swelling experiment and cotton granuloma, in experimental mice was conducted to observe the anti-inflammatory effect of vinegar-processed RAR. The inflammatory cytokines of model rats were determined by enzyme-linked immunosorbent assay (ELISA). Liquid Chromatography-Quadrupole-Time of Flight mass spectrometer Detector (LC-Q-TOF) was used to analyse the chemical compositions of the RARs before and after vinegar processing.

Results

Neither obvious changes in mice nor death phenomena were observed as the amount of vinegar-processed RAR in crude drug was set at 2.1 g/kg. Vinegar-processed RAR could significantly prolong the latency, reduce the writhing reaction time to reduce the severity of ear swelling and foot swelling, and remarkably inhibit the secretion of Interleukin-1β(IL-1β), Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) proinflammatory cytokines. The content of twelve saponins (e.g., Eleutheroside K) in RAR was decreased after vinegar processing, but six other types (e.g., RDA) were increased.

Conclusions

These results revealed that vinegar processing could not only improve the analgesic and anti-inflammatory effects of RAR but also reduce its own toxicity.

Trial registration

Not applicable.

Therapeutic benefits of Indole-3-Carbinol in adjuvant-induced arthritis and its protective effect against methotrexate induced-hepatic toxicity

BACKGROUND

Rheumatoid arthritis (RA) being an incapacitating disease requires early effective intervention. Considering Methotrexate (MTX)- the first line of treatment for RA- intoxicates the liver; therefore, alternative therapies with similar efficacy yet lower cytotoxicity are desired. Indole-3-Carbinol (I3C) which is found in cruciferous vegetables was examined for its possible therapeutic potentials in comparison with MTX by investigating its anti-inflammatory, anti-arthritic, anti-oxidant, and hepatoprotective potentials in adjuvant-induced arthritis (AIA) rat model.

METHODS

Arthritis was induced in Sprague Dawley rats by injection of Complete Freund's Adjuvant (CFA). Arthritic rats were treated with I3C and/or MTX. To examine the anti-inflammatory and anti-arthritic effect, the following parameters were assessed: body weight, macroscopic scoring of the hind paw, the level of the pivotal cytokines (TNF-α, IL-6) heavily involved in the pathogenesis, spleen index, and erythrocyte sedimentation rate. At a histological level, the tibiotarsal joint was stained with several specific stains. To assess the hepatoprotective and anti-oxidant effects, several oxidative stress parameters were monitored, and the liver histology was examined.

RESULTS

Both I3C and MTX attenuated the inflammation that was aggravated by arthritis by downregulating the inflammatory markers and mediators and alleviating the histopathological changes affecting the tibiotarsal joint. I3C attenuated the liver impairment that was initiated by arthritis and MTX treatment. It did so by downregulating the pro-oxidants and up-regulating the anti-oxidant defenses and by reducing the pathological changes affecting the liver.

CONCLUSION

Our results suggest that I3C is as potent as MTX as an anti-inflammatory and anti-arthritic agent. In addition, I3C does so while protecting the liver from damage as opposed to MTX.

DNA hypermethylation of SFRP2 influences the pathology of rheumatoid arthritis through the canonical Wnt signaling in model rats

In this work, the expression of secreted frizzled related protein 2 (SFRP2) in rheumatoid arthritis (RA) model rats and the mechanisms of SFRP2 on the RA pathogenesis were investigated. Data suggested that SFRP2 was significantly down-regulated in RA model rats compared with normal control, and overexpression of SFRP2 suppressed the RA pathogenesis and the canonical Wnt signaling in fibroblast-like synovial cells (FLS) from RA model rats, whereas knockdown of SFRP2 got an opposite observation. Interestingly, 5-azadC treatment up-regulated the SFRP2 expression, inhibited the FLS proliferation, suppressed the expression of IL-6 and IL-8 and the fibronectin production, suggesting that the decreased SFRP2 in RA model rats was due to the DNA methylation. Furthermore, DNMT1 knockdown up-regulated the SFRP2 expression, DNMT1 overexpression inhibited the SFRP2, and the quantitative methylation-specific PCR (qMSP) confirmed that the DNMT1 has direct methylation roles for the SFRP2 promoter, leading to a regulation of FLS proliferation and fibronectin expression in RA model rats. In addition, up-regulated MeCP2 was involved in the SFRP2 regulation and the pathogenesis of RA model rats, and MeCP2 and DNMT1 have synergistic inhibition roles in the SFRP2 expression. Combination of DNMT1 and DNA methylation may be a promising treatment strategy for individuals with RA in which SFRP2 is down-regulated.

Dihydromyricetin relieves rheumatoid arthritis symptoms and suppresses expression of pro-inflammatory cytokines via the activation of Nrf2 pathway in rheumatoid arthritis model

Rheumatoid arthritis (RA) is a systemic inflammatory and autoimmune disease. In this research, we estimated the protective effects of Dihydromyricetin (DMY) on RA induced by Complete Freund's Adjuvant (CFA). We found that DMY effectively relieved rheumatoid arthritis symptoms, such as body weight change, paw swelling and rheumatoid arthritis scores. In addition, we also observed that DMY significantly lowered the immune organ indexes (including thymus and spleen) and exhibited the anti-inflammatory effect in CFA-induced rheumatoid arthritis. The results demonstrated that the increased expression levels of interleukin-1β (IL-1β), interleukin-6(IL-6), tumor necrosis factor-α (TNF-α) were significantly inhibited by DMY. Furthermore, the key inflammatory mediator, cyclooxygenase-2 (COX-2) was markedly lowered after treatment with DMY. A mechanistic study indicated that DMY could up-regulate the down-regulation levels of the mRNA and protein of Nrf2, HO-1 and NQO1. Moreover, the Nrf2 activation of DMY was abolished by Nrf2 inhibitor brusatol. Thus, DMY inhibits the expressions of pro-inflammatory cytokines via activating Nrf2 pathway in RA model, which suggests that DMY has potential for further investigation as a candidate anti-arthritic agent in future.