Salidroside suppresses cell growth and inflammatory response of fibroblast-like synoviocytes via inhibition of phosphoinositol-3 kinase/threonine kinase signaling in rheumatoid arthritis.

BACKGROUND: Salidroside (Sal) is a natural product commonly isolated from Rhodiola rosea L., which has been found to have numerous pharmacological activities (e.g., ameliorating apoptosis and inflammation, and acting as an antioxidant) in various diseases, but its concrete function in rheumatoid arthritis (RA) has not been revealed yet. Here, we aimed to explore the specific role and underlying mechanisms of Sal in RA-fibroblast-like synoviocytes (RA-FLSs). METHODS: Cell counting kit 8 (CCK-8) was used to assess the viability of normal-FLSs and RA-FLSs. Cell apoptosis in RA-FLSs was evaluated by flow cytometry. Western blotting was prepared to examine the levels of apoptosis- and signaling-related proteins. Wound-healing and Transwell assays were conducted to examine RA-FLSs migration and invasion. Enzyme-linked immunosorbent assay (ELISA) was used to assess the effect of Sal on tumor necrosis factor-alpha (TNF-α)-induced inflammation in RA-FLSs. RA animal model was established through complete Freund's adjuvant (CFA) induction, and the histopathological changes in synovial tissues of the rat model were analyzed by H&E staining. RESULTS: RA-FLSs were treated with 200 µM Sal for 24 h, and cell viability was significantly suppressed. Sal promoted RA-FLSs apoptosis. The migratory and invasive abilities of RA-FLSs were markedly inhibited by Sal. Sal incubation reduced the levels of inflammatory cytokines interleukin­8 (IL-8), IL-1ß, and IL­6 in RA-FLSs under the stimulation of TNF­α. Subsequently, Sal downregulated phosphorylated phosphatidylinositol­3 kinase (p-PI3K) and protein kinase (p-AKT) expression in RA-FLSs. After the treatment with pathway activator 740Y­P (20 µM) in RA-FLSs, the promotive effect of Sal on cell apoptosis was reversed, and inhibitory effects of it on cell viability, migration, invasion, and inflammatory response were abolished. Sal inhibited RA development in the CFA-induced rat model. CONCLUSION: Sal suppressed cell growth and inflammation in RA-FLSs by inactivating PI3K/AKT-signaling pathways.

Assessment of antiarthritic potential of Asparagus dumosus using formaldehyde and CFA-induced arthritic models in rats via modulation of oxidative stress biomarkers and mRNA expression of IL-1b, IL-6, RANKL, OPG, TNF-α and COX-2.

Medicinal plants play a pivotal role in the prevention of chronic non-communicable diseases including arthritis. Despite the traditional use of Asparagus dumosus in arthritis, it has not been studied yet for its effectiveness in arthritis. This study was aimed to explore the antiarthritic potential of A. dumosus in formaldehyde and complete Freund's adjuvant (CFA)-induced arthritic rats. Body weight, arthritic index, hepatic oxidative stress, hematological, biochemical and inflammatory markers were assessed using ELISA, whilst qRT-PCR studies were carried out for the mRNA expression of IL-1b, IL-6, RANKL, OPG, TNF-α and COX-2 genes. GCMS and HPLC analysis were performed to identify the secondary metabolites of A. dumosus. From day 8 to 28 post-administration of formaldehyde and CFA, oral administration of A. dumosus (600, 300 and 150 mg/kg) showed a noteworthy improvement (p < 0.001) in the body weights, immune organ weights, serum levels of rheumatoid (RA) factor, C-reactive protein, TNF-α and IL-6 levels in arthritic rats similar to the effect of piroxicam and methotrexate. Subsequently, the administration of A. dumosus to formaldehyde and CFA-challenged rats, caused a marked decrease (p < 0.001) in the mRNA expression of IL-1b, IL-6, OPG, RANKL, TNF-α and COX-2 genes in treated rats. Likewise, when assessed for antioxidant potential, A. dumosus produced a pronounced (p < 0.001) reduction in malondialdehyde (MDA) levels and hydrogen peroxide (H2O2) production, whilst a dose-dependent (p < 0.001) increase in catalase (CAT) and superoxide dismutase (SOD) activities was recorded. GCMS profiling of A. dumosus presented benzaldehyde, 3-hydroxy-4-methoxy-, 1-decanol and undecane as plant compositions, whereas HPLC fingerprinting displayed quercetin, benzaldehyde, 3-hydroxy-4-methoxy-, gallic acid and cinnamic acid as plants constituents. These results depict that A. dumosus possesses anti-arthritic effect mediated possibly through attenuation of arthritic indices, chronic inflammatory and oxidative stress biomarkers along with down-regulation in the mRNA expression of arthritic candid genes.

Investigating antiarthritic potential of polyherbal emulgel.

BACKGROUND: Rheumatoid arthritis (RA) is an inflammation of joints with increased cellularity of synovial tissue. Allopathic drugs possess several adverse effects, which have led to increase in the utilization of herbal medicines. Polyherbal emulgel resolves the bioavailability issue associated with hydrophobic drugs and can be used effectively in the treatment of RA. OBJECTIVES: The present study aimed at the formulation of polyherbal emulgel, and evaluation of in vitro anti-inflammatory activity and in vivo antiarthritic activity. METHODS: Seven emulgels F-1 to F-7 were optimally formulated. In vitro anti-inflammatory activity was determined using protein denaturation method employing Diclofenac sodium as the standard. In antiarthritic study Complete Freund's Adjuvant (CFA) model was used. The various parameters were assessed, like paw volume, body weight, hematological parameters, antioxidant parameters, Rheumatic factor (RF), and histopathological study of ankle joint. RESULTS: F-4 and F-7 were found to be optimized formulations as compared to other formulations. The in vitro anti-inflammatory activity was found to be highest in F-4 with IC50 7.74 and F-7 with IC50 8.87 in comparison with Diclofenac sodium having IC50 57.0. Both formulations F-7 and F-4 showed a significant reduction in paw volume and normalization of body weights. The formulation F-7 even showed more potent antiarthritic activity than F-4 by decreasing white blood cells (WBC), lymphocytes, increasing packed cell volume (PCV), neutrophils, superoxide dismutase (SOD), catalase and decreasing malondialdehyde (MDA) levels in serum. This was further confirmed by histopathological study. CONCLUSION: As an anti-inflammatory agent, this newly developed emulgel was found to possess more therapeutic efficacy than commercially available diclofenac sodium.

Appraisal of anti-arthritic potential of Coronopus didymus (L.) Sm. aqueous extract and its safety study in Wistar rats.

The current study aimed to find out the anti-arthritic activity and safety study of Coronopus didymus aqueous extract (CDAE) as well as its chemical characterization by HPLC-DAD. Safety study including acute and subacute toxicity studies of the plant aqueous extract was also performed. In complete Freund's adjuvant-induced arthritic model (CFA), 0.15 ml CFA was injected in the left hind paw at day 1 in all rats except normal rats. Treatment with CDAE at 200, 400, and 800 mg/kg and methotrexate (1 mg/kg) was administered at day 8 and continued till 28th day using oral gavage. The CDAE considerably (p < 0.05) reduced the paw swelling and arthritic score, and reinstated the body weight and blood parameters. The CDAE considerably modulated superoxide dismutase, catalase, reduced glutathione, and malondialdehyde level in liver homogenate in contrast to disease control. The CDAE at 400 mg/kg considerably reduced IL-6, IL -1ß, COX-2, and NF-ĸß, whereas elevated IL-10, IL-4, and I-kappa ß as equated to disease and standard groups. The LD50 of CDAE > 2000 mg/kg. In subacute toxicity study, CDAE at 200-800 mg/kg did not exhibit clinical signs of toxicity, mortality, hematological, biochemical, and histological alteration in the liver heart, kidney, and lungs in contrast to the normal group. It was concluded that the presence of delphinidine-3-glucoside, diosmetin, 3-feruloyl-4,5-dicaffeoyl quinic acid, and gallic acid in CDAE might be accountable for its anti-arthritic activity and safe use for a long period.

Curcuminoids-enriched extract and its cyclodextrin inclusion complexes ameliorates arthritis in complete Freund's adjuvant-induced arthritic mice via modulation of inflammatory biomarkers and suppression of oxidative stress markers.

Curcuma longa extract and its marker curcuminoids have potential use in inflammatory conditions. However, curcuminoids solubility and bioavailability are major hindrances to their bioactivity. The current study investigated green extraction-based curcuminoids-enriched extract (CRE) prepared from C. longa and its cyclodextrin inclusion complexes, i.e., binary inclusion complexes (BC) and ternary inclusion complexes (TC), in complete Freund's adjuvant (CFA)-induced mice for their comparative anti-arthritic efficacy. CRE, BC, and TC (2.5 and 5 mg/kg) with the standard drug diclofenac sodium (13.5 mg/kg) were orally administered to mice for 4 weeks. Variations in body weight, hematological and biochemical parameters, along with gene expression analysis of arthritis biomarkers, were studied in animals. The histopathological analysis and radiographic examination of joints were also performed. CRE, BC and TC treatment significantly restored the arthritic index, histopathology and body weight changes. The concentration of C-reactive protein, rheumatoid factor and other liver function parameters were significantly recovered by curcuminoids formulations. The pro-inflammatory cytokines (NF-κB, COX-2, IL-6, IL-1ß, and TNF-α) gene expression was considerably (p < 0.001) downregulated, while on the other side, the anti-inflammatory genes IL-4 and IL-10 were upregulated by the use of CRE and its complexes. The concentration of antioxidant enzymes was considerably (P < 0.001) recovered by CRE, BC and TC with marked decrease in lipid peroxidation, erosion of bone, inflammation of joints and pannus formation in comparison to arthritic control animals. Therefore, it is concluded that green CRE and its cyclodextrin formulations with enhanced solubility could be considered as an applicable therapeutic choice to treat chronic polyarthritis.

Comprehensive phytochemical characterization of Persea americana Mill. fruit via UPLC/HR-ESI-MS/MS and anti-arthritic evaluation using adjuvant-induced arthritis model.

Persea americana Mill. (avocado fruit) has many health benefits when added to our diet due to various pharmacological activities, such as preventing bone loss and inflammation, modulating immune response and acting as an antioxidant. In the current study, the total ethanol extract (TEE) of the fruit was investigated for in vitro antioxidant and anti-inflammatory activity via DPPH and cyclooxygenase enzyme inhibition. Biological evaluation of the antiarthritic effect of the fruit extract was further investigated in vivo using Complete Freund's Adjuvant (CFA) arthritis model, where the average percentages of body weight change, inhibition of paw edema, basal paw diameter/weight and spleen index were estimated for all animal groups. Inflammatory mediators such as serum IL-6 and TNF-α were also determined, in addition to histopathological examination of the dissected limbs isolated from all experimental animals. Eighty-one metabolites belonging to different chemical classes were detected in the TEE of P. americana fruit via UPLC/HR-ESI-MS/MS. Two classes of lyso-glycerophospholipids; lyso-glycerophosphoethanolamines and lysoglycerophosphocholines were detected for the first time in avocado fruit in the positive mode. The TEE of fruit exhibited significant antioxidant and anti-inflammatory activity in vitro. In vivo anti-arthritic activity of the fruit TEE improved paw parameters, inflammatory mediators and spleen index. Histopathological findings showed marked improvements in the arthritic condition of the excised limbs. Therefore, avocado fruit could be proposed to be a powerful antioxidant and antiarthritic natural product.

Immunomodulatory Effects of Combined Nicotinic Acid and Prednisolone in Adjuvant-induced Arthritis.

BACKGROUND: The combination of two drugs may lead to better results while reducing the need for each medication. OBJECTIVE: This study aimed to explore the synergistic benefits of combination therapy by suboptimal dose of niacin (Nic.) and prednisolone (Pred.) in an experimental model of Rheumatoid arthritis (RA). METHODS: About 50 male Wistar rats (weighing 150 - 160 grams) were randomly divided into five groups of ten, including healthy and RA groups treated with Nic. (80 mg/kg-orally), or Pred. (2 mg/kg-orally), and/or co-administration of Nic. and Pred. (half doses with each one-orally). RA was induced by the injection of complete Freund's adjuvant into the hind paw of each rat. All treatments were initiated on the fifth day following the induction and continued until day 30 post-induction. RESULTS: The combined Nic. and Pred. at half doses promoted a significant regression in the severity of the established RA, which is more pronounced than full doses of either drug alone. Combination therapy promoted a reduction in some hematological and biochemical RA parameters, like neutral red uptake by phagocytic cells, myeloperoxidase, nitric oxide, and C-reactive protein, more profound than each drug alone. Combined treatment caused a greater decrease in IFN-γ expression than other treatments in the area of plantar joints. All treatments were effective in increasing the expression of the IL-10 in the area of plantar joints. Prednisolone was less effective in reducing the expression of the TNF-α in the area of plantar joints than the other group. CONCLUSION: This combination may be a useful approach to controlling RA.

Curative potential of Populus ciliata Wall ex. Royle extract against adjuvant-induced arthritis and peripheral neuropathy in Wistar rats.

Populus ciliata (PCCR) is traditionally used to treat muscular swelling, inflammation, pain, and fever. The current study was designed to validate the potential of aqueous ethanolic extract of the plant against inflammation, peripheral neuropathy, and pain in arthritic rats. The PCCR was chemically characterized by gas chromatography-mass spectroscopy and high-performance liquid chromatography. In vitro antioxidant, and in vitro anti-inflammatory assays were carried out on PCCR. For anti-arthritic potential, Wistar rats' rear paws were injected with 0.1 ml Complete Freund's Adjuvant using methotrexate (3 mg/kg/week) as standard control. PCCR at 100, 200, and 400 mg/kg was given orally to arthritic rats for 21 days. The PCCR exhibited significant inhibition of bovine serum albumin denaturation (IC-50: 202.1 µg/ml), egg albumin denaturation (IC-50:553.5 mg/ml) and RBC membrane stabilization (IC-50: 122.5 µg/ml) and antioxidant (IC-50 = 49.43 µg/ml) activities. The PCCR notably decreased the paw diameter and increased body weight of treated arthritic animals as equated to diseased control. The treatment notably (p < 0.05-0.0001) decreased malondialdehyde, and increased superoxide dismutase, reduced glutathione, and catalase in the liver and sciatic nerve homogenate in compared to diseased rats. The PCCR treatment remarkably (p < 0.05-0.0001) regulated the levels of nor-adrenaline and serotonin in sciatic nerve in contrast to diseased rats. Treatment with PCCR improved the motor activity, pain, ligament degeneration, and synovial hyperplasia in arthritic rats. Moreover, PCCR significantly (p < 0.01-0.0001) decreased the IL-6 and TNF-α. It is evident from the current study that PCCR had ameliorated polyarthritis and peripheral neuropathy through reduction of inflammatory markers, and improvement of oxidative stress might be due to presence of phenolic acids, flavonoids, phytosterols, and other fatty acids.

Vetiver aerial parts and roots ameliorate rheumatoid arthritis in complete Freund's adjuvant rat model, a phytochemical profiling and mechanistic study.

ETHNOPHARMACOLOGICAL RELEVANCE: Vetiver (Chrysopogon zizanioides) is indigenous to India where it is traditionally used to relief rheumatisms, lumbagos and sprains. Vetiver anti-inflammatory activity has not been previously investigated, and its specific interactions with body inflammation cascade remain largely unknown. AIM OF THE STUDY: The present work was performed to validate the ethnobotanical use of the plant and compare the anti-inflammatory activities of the ethanolic extracts of the most traditionally used part (aerial part) to that of the root. Furthermore, we attempt to reveal the molecular mechanism of this anti-inflammatory activity in correlation to the chemical composition of C. zizanioides aerial (CA) and root parts (CR). MATERIALS AND METHODS: Ultraperformance liquid chromatography coupled to high resolution mass spectrometry (UHPLC/HRMS) was used for comprehensive analysis of both CA and CR. The anti-inflammatory effect of both extracts was evaluated in complete Freund's adjuvant (CFA)-induced RA model in Wistar rats. RESULTS: Phenolic metabolites were predominant in CA and 42 were identified for the first time, while only 13 were identified in CR. Meanwhile, triterpenes and sesquiterpenes were confined to the root extract. In CFA arthritis model, CA showed better anti-inflammatory activity than CR marked by an increase in serum level of IL-10 with simultaneous decrease in pro-inflammatory markers; IL-6, ACPA and TNF-α and was evident in histopathological examination. This anti-inflammatory effect was accompanied by down-regulation of JAK2/STAT3/SOCs3, ERK1/ERK2, TRAF6/c-FOS/NFATC1, TRAF6/NF-κB/NFATC1 and RANKL pathways which were all upregulated after CFA injection. These pathways were modulated to larger extent by CA, except for ERK1/ERK2 which was downregulated more effectively by CR. This differential effect between CA and CR can be explained by the variability in their phytoconstituents profile. CONCLUSION: In agreement with the ethnobotanical preference, CA extract was more effective than CR extract in reducing the symptoms of RA probably due to its enrichment with flavonoids, lignans, and flavolignans. Both CA and CR reduced the production of inflammatory cytokines through modulating various biological signaling pathways. These findings support the traditional use of vetiver leaves as a remedy for RA and suggest that the use of the whole plant may offer advantage by synergistically affecting more inflammatory pathways.

"Cerastes snake venom as a promising approach in the management of complete Freund's adjuvant-induced rheumatoid arthritis in rats: Involvement of RANKL and JAK/STAT pathway".

ETHNOPHARMACOLOGICAL RELEVANCE: Cerastes is a snake found mainly in the Egyptian desert. Many studies were performed to explain the possible snake venom's pharmacological therapeutic effect in different autoimmune diseases. One of the most common auto-immune diseases is rheumatoid arthritis. Rheumatoid arthritis is characterized by a high release of pro-inflammatory and immune-modulatory cytokines. The reduction of these markers can indicate how effective is the administered drug. AIM OF THE STUDY: This study aims to explore the potential pharmacological effects of cerastes venom in experimentally-induced RA in rats using Complete Freund's adjuvant - via different mechanisms - by assessing various tissue and serum parameters. MATERIALS AND METHODS: The rats were assigned to negative control group, cerastes control group, positive control group, dexamethasone-treated group, infliximab-treated group, and cerastes-treated group. The study ended on the 20th day when serum and tissue samples were prepared for further evaluation of reduced glutathione, malondialdehyde, rheumatoid factor, tumor necrosis factor-α, interleukin-6, and nuclear factor kappa-light-chain-enhancer of activated B cells as well as relative expression of phosphorylated Janus-kinase, phosphorylated signal transducers and activators of transcription, nuclear factor erythroid 2-related factor 2, and receptor activator of nuclear factor Kappa-B ligand. In addition, a histopathological examination of different groups' knees joints, and spleen was done. RESULTS: The results showed a significant improvement of arthritis induced in the cerastes-treated group in contrast to the positive control group in all assessed parameters. In addition, significant improvement of arthritis was observed in the histopathological examination of different groups' knees joints, and spleen. CONCLUSION: These results revealed that cerastes snake venom has potent anti-inflammatory and immunomodulatory effects and can be used in the management of arthritis.

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.

Endogenous Derivatives of Linoleic Acid and their Stable Analogs Are Potential Pain Mediators.

Psoriasis is characterized by intense pruritus, with a subset of individuals with psoriasis experiencing thermal hypersensitivity. However, the pathophysiology of thermal hypersensitivity in psoriasis and other skin conditions remains enigmatic. Linoleic acid is an omega-6 fatty acid that is concentrated in the skin, and oxidation of linoleic acid into metabolites with multiple hydroxyl and epoxide functional groups has been shown to play a role in skin barrier function. Previously, we identified several linoleic acid‒derived mediators that were more concentrated in psoriatic lesions, but the role of these lipids in psoriasis remains unknown. In this study, we report that two such compounds-9,10-epoxy-13-hydroxy-octadecenoate and 9,10,13-trihydroxy-octadecenoate-are present as free fatty acids and induce nociceptive behavior in mice but not in rats. By chemically stabilizing 9,10-epoxy-13-hydroxy-octadecenoate and 9,10,13-trihydroxy-octadecenoate through the addition of methyl groups, we observed pain and hypersensitization in mice. The nociceptive responses suggest an involvement of the TRPA1 channel, whereas hypersensitive responses induced by these mediators may require both TRPA1 and TRPV1 channels. Furthermore, we showed that 9,10,13-trihydroxy-octadecenoate‒induced calcium transients in sensory neurons are mediated through the Gßγ subunit of an unidentified G-protein coupled receptor (GPCR). Overall, mechanistic insights from this study will guide the development of potential therapeutic targets for the treatment of pain and hypersensitivity.

Chondroprotective Effects of Grapefruit (Citrus paradisi Macfad.) Juice in a Complete Freund's Adjuvant Rat Model of Knee Osteoarthritis.

Osteoarthritis (OA) is a common disorder that can affect any joint in the human body. This study aimed to examine the anti-arthritic properties of high and low doses of grapefruit juice (GFJ), as grapefruit appears to contain anti-inflammatory biochemicals. Forty male Sprague-Dawley rats weighing 170-180 g were divided into five groups. These groups comprised the untreated control group and osteoarthritic (Osteo) rats administered intra-articular injections of Freund's complete adjuvant (CFA; 0.5 mL; 1 mg/mL) as follows: OA rats administered low doses of GFJ (Osteo+GFJ (low); 5 mL/kg body weight (BW)); OA rats administered high doses of GFJ (Osteo+GFJ (high); 27 mL/kg BW); and OA rats administered diclofenac sodium (Osteo+Diclo) as a reference drug. Injections of CFA induced OA, as indicated by a significant increase in the serum levels of the inflammatory biomarkers C-reactive protein (CRP), interleukin-1ß (IL-1ß), and (prostaglandin (PGE2), as well as matrix metalloproteinases (MMP-1) and cathepsin K. The synovial levels of glycosaminoglycans (GAGs), tumor necrosis factor (TNF-α), and interleukin 6 (IL-6) also increased, with a concomitant reduction in osteocalcin levels. The administration of either high or low doses of GFJ reduced CRP, IL-1ß, PGE2, MMP-1, cathepsin K, and osteocalcin while increasing the synovial levels of GAGs, TNF-α, and IL-6, slowing cartilage degradation and boosting joint function. The results showed comparable histopathological and biochemical responses. A comparison of the treatments showed that high-dose GFJ had a greater chondroprotective effect than low-dose GFJ.

Anti-inflammatory and analgesic effect of Forsythiaside B on complete Freund's adjuvant-induced inflammatory pain in mice.

Chronic pain is frequently reported in clinical practice. Therefore, it is important to identify effective therapy to relieve pain. In this work, we selected Forsythoside B (FB), a phenylethanoid glycoside isolated from Forsythia suspensa (Thunb.) Vahl, to evaluate its effect in modulating inflammatory pain induced by complete Freund's adjuvant (CFA) and the involved mechanisms. We discovered that FB could attenuate inflammatory pain triggered by CFA injection and exert anti-anxiety effects. In detail, proinflammatory cytokines, consisting of IL-6 and TNF-α, were decreased after FB administration in the CFA-injected mice. Furthermore, the FB application ameliorated the activation of ionized calcium-binding adaptor molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP), the microglia and astrocytes markers respectively. Therefore, our findings indicate that FB could be a promising treatment for chronic inflammatory pain.

Validation of traditional claims of anti-arthritic efficacy of trans-Himalayan snow mountain garlic (Allium ampeloprasum L.) extract using adjuvant-induced arthritis rat model: A comparative evaluation with normal garlic (Allium sativum L.) and dexamethasone.

ETHNOPHARMACOLOGICAL RELEVANCE: Snow Mountain Garlic (SMG) (Allium ampeloprasum L.) is a wild trans-Himalayan member of the genus Allium, valued for its anti-inflammatory and anti-arthritic properties in the mountain folk medicinal system (Sowa-Rigpa). Despite its age-old medicinal usage by traditional therapists and the native population for various ailments including rheumatism, there is no scientific validation of its phyto-pharmaceutical merits. AIM OF THE STUDY: The present pre-clinical study compared the in-vivo anti-arthritic effects of SMG with reported efficacy doses of normal garlic (Allium sativum L.) extract and dexamethasone in a complete Freund's adjuvant (CFA)-induced arthritis rat model. MATERIALS AND METHODS: The female Wistar rats were immunized by the subplannter injection of CFA into the right hind footpad. Aqueous extracts of SMG and normal garlic were administered orally at a dose of 250 mg/kg and 500 mg/kg for 28 days. Dexamethasone was used as positive control drug. Behavioral parameters including paw markers, arthritis index, joint stiffness, body weight change, etc. were measured. Also, the changes in histopathological indices, hematological profile, inflammatory mediators, and serum cytokines level was determined. RESULTS: Treatment of rats with SMG extracts significantly (p < 0.001) prevented the reduction in body weight and hematological changes as well as ameliorated clinical symptoms such as arthritic index, joint stiffness, arthritis score, edema, hyperalgesia, and histopathological indices. This was associated with a significant reduction in the serum levels of RF, CRP, anti-CCP, and proinflammatory cytokines exhibiting strong anti-arthritic potential. SMG extracts could also significantly down regulate the NF-κB, COX-2, and iNOS expression in the ankle joint tissues. CONCLUSIONS: The present study is the first attempt to validate the phyto-pharmaceutical efficacy of this folk garlic variety from the trans-Himalayan region. Overall, SMG extract showed remarkable preventive anti-inflammatory and anti-arthritic activities which were closely comparable to therapeutic effects of dexamethasone and at par or even better than normal garlic w.r.t. several study parameters.

Analgesic and anti-inflammatory potential of ethanolic extract from Serjania erecta leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: The infusion of Serjania erecta Radlk (Sapindaceae) (popular name "cipó-cinco-folhas") leaves is used in popular medicine to treat back pain. The anti-inflammatory, anti-hyperalgesic and anti-nociceptive properties of the ethanolic extract from S. erecta leaves (EESE) has not been yet completely clarified. AIM OF THE STUDY: The present study investigated the anti-hyperalgesic, anti-nociceptive and anti-inflammatory properties of EESE in experimental models in mice. MATERIAL AND METHODS: EESE was fractionated by chromatographic techniques and the compound was identified by nuclear magnetic resonance (NMR), infrared (IR) spectrum, ultraviolet (UV) methods. Mice received a single dose of EESE by oral route (30, 100, and 300 mg/kg, p.o.) and were submitted to nociception induced by formalin, pleurisy induced by carrageenan and peritonitis induced by zymosan models. Mice also received EESE (30 and 100 mg/kg, p.o.) for 22 days in Complete Freund Adjuvant (CFA) model and another group received EESE for 7 days (30 and 100 mg/kg, p.o.) in pleurisy induced by Bacillus Calmette-Guerin (BCG). The cytotoxicity (MTT), phagocytic and chemotactic inhibitory activities of EESE were performed in in vitro assays. RESULTS: The fractionation of EESE led to the identification of kaempferol-3-O-α-L-rhamnopyranoside. The oral administration of all doses of EESE decreased the nociceptive response induced by formalin. EESE significantly inhibited leukocyte migration in carrageenan-induced pleurisy and zymosan peritonitis models. The daily administration of EESE during for 7 days inhibited the leukocyte migration and the mycobacteria growth of pleural material obtained from animals which received BCG. EESE significantly reduced edema, cold allodynia and mechanical hyperalgesia responses induced by CFA. EESE did not induce cytotoxicity, and also decreased the leukocyte phagocytic activity, as well as, neutrophil chemotaxis. CONCLUSIONS: EESE showed analgesic and anti-inflammatory properties in acute and persistent experimental models in mice. EESE also reduced in vitro leukocyte chemotaxis and phagocytic activity without inducing cytotoxicity. The continuous oral treatment with EESE was effective against hyperalgesia and inflammation and these results could explain the popular use of S. erecta as an analgesic natural agent.

Analgesic effects of saikosaponin A in a rat model of chronic inflammatory pain.

Saikosaponin A (SSA) is the main active ingredient of roots of the East Asian medicinal plant, Bupleurum falcatum L. The present study was aimed at delving into the analgesic properties of SSA in a model of chronic inflammatory pain. To this end, rats were initially treated intraplantarly with complete Freund's adjuvant for induction of hyperalgesia. Twenty-four hours later, rats were acutely treated with SSA (0, 1 and 2 mg/kg, i.p.) and exposed to the Von Frey monofilament test or Randall-Selitto paw pressure test for assessment of mechanical hyperalgesia. Treatment with 2 mg/kg SSA had analgesic effects: the nocifensive reaction (paw withdrawal) occurred later and required application of the nociceptive stimulus at a stronger pressure. The analgesic effects of SSA were of magnitude comparable to that of the effects exerted by the reference compound, acetyl salicylic acid (100 mg/kg, i.p.). The well-described anti-inflammatory properties of SSA likely underlie its analgesic effects.

Intrathecal liproxstatin-1 delivery inhibits ferroptosis and attenuates mechanical and thermal hypersensitivities in rats with complete Freund's adjuvant-induced inflammatory pain.

Previous studies have confirmed the relationship between iron-dependent ferroptosis and a peripheral nerve injury-induced neuropathic pain model. However, the role of ferroptosis in inflammatory pain remains inconclusive. Therefore, we aimed to explore whether ferroptosis in the spinal cord and dorsal root ganglion contributes to complete Freund's adjuvant (CFA)-induced painful behaviors in rats. Our results revealed that various biochemical and morphological changes were associated with ferroptosis in the spinal cord and dorsal root ganglion tissues of CFA rats. These changes included iron overload, enhanced lipid peroxidation, disorders of anti-acyl-coenzyme A synthetase long-chain family member 4 and glutathione peroxidase 4 levels, and abnormal morphological changes in mitochondria. Intrathecal treatment of liproxstatin-1 (a ferroptosis inhibitor) reversed these ferroptosis-related changes and alleviated mechanical and thermal hypersensitivities in CFA rats. Our study demonstrated the occurrence of ferroptosis in the spinal cord and dorsal root ganglion tissues in a rodent model of inflammatory pain and indicated that intrathecal administration of ferroptosis inhibitors, such as liproxstatin-1, is a potential therapeutic strategy for treating inflammatory pain.

Evaluation of the anti-arthritic activity of Rhuflex-F - A proprietary Ayurvedic herbomineral formulation in albino rats.

Background: Rhuflex-F is a proprietary Ayurvedic herbo-mineral formulation clinically used to combat and relieve stiffness in joints and muscles, reduce edema, restore mobility, and also effective in relieving the symptoms of other autoimmune illnesses that lead to rheumatism. Aims: The aim and objective of the research study is to evaluate the efficacy of Rhuflex-F against in vitro protein denaturation and in vivo Freund's adjuvant-induced arthritis in albino rats. Materials and methods: In vitro inhibition of protein denaturation activity was carried out using bovine serum albumin. For in vivo activity, arthritis was induced by complete Freund's adjuvant in albino rats. Rhuflex-F (135-270 mg/kg, po) was administered for 30th days in arthritic rats, and effects were assessed on primary and secondary paw edema, on pain response, hematological, serum biochemical parameters (serum transaminases, alkaline phosphatase, urea, uric acid, and orosomucoid), and serum anti-oxidant parameters and adrenal ascorbic acid. Results: Aqueous extract of Rhuflex-F showed in vitro protein denaturation inhibitory activity in a dose-dependent manner. Rhuflex-F showed nonsignificant decrease in primary and secondary paw edema with reduced pain response, some reversal effects on hematological parameters such as white blood cell and red blood cell related parameters and serum orosomucoid and adrenal ascorbic acid in comparison to Fruend's adjuvant control group. Further, Rhuflex-F reversed Freund's adjuvant-induced adverse effects on oxidant status in the serum of albino rats. Conclusion: Result of the present study suggested that Rhuflex-F formulation has anti-inflammatory activity, may be due to the inhibition of protein denaturation in vitro and in vivo anti-arthritic activity against complete Freund's adjuvant-induced arthritis in albino rats.

Evaluating the effect of ursodeoxycholic acid (UDCA) in comparison with dexamethasone and diclofenac in a rat model of rheumatoid arthritis.

Ursodeoxycholic acid (UDCA) is known for its major effects on the liver, but its impact on autoimmune diseases is not well understood. This study aimed to assess the effectiveness of UDCA in controlling rheumatoid arthritis (RA) in an in vivo setting. Experimental RA was induced in rats using Freund's complete adjuvant, and the effects of UDCA (50,100 mg/kg) were compared to those of dexamethasone and diclofenac by measuring changes in paw size, IL-17, pro-inflammatory cytokines, oxidative stress (GSH, MDA), and radiological changes. The administration of UDCA resulted in decreased cartilage damage, reduced paw edema, and a decrease in the release of pro-inflammatory cytokines and oxidative stress. Additionally, X-ray joint alterations were observed in the UDCA-treated group compared to the dexamethasone and diclofenac groups. These results suggest that UDCA has anti-rheumatoid arthritis properties due to its ability to minimize oxidative stress and inflammation in arthritis-affected rats.