Search

Systemic autoimmune disease of rheumatoid arthritis (RA) is a severe case of joint deformity. Serious off-targeted drugs are not capable of curing RA and lead to increased risk of infection. Nanoparticles-based arthritis therapy is a promising approach to promote effective treatment strategy in inflammatory tissues. In particular, an inorganic-metal hybrid form of core–shell nanostructure has a significant role in the drug application due to its unique properties arising from either core or shell materials. Presently, the Au–SiO2 core–shell nanomaterials with an average diameter of 78 nm were successfully synthesized. The nanomaterials revealed a very high sinapic acid (SA) loading to eliminate the inflammatory response in RA by avoiding the side effects of conventional drugs. Various characterization techniques revealed that the as-fabricated Au–SiO2 has a higher-contrast core and aggregates of SiO2 on their surfaces/of the shell. Besides, Au–SiO2 core–shell exhibits the large extended pore structure to store a large quantity of SA drugs. Then, the mice were treated with different doses of SA loaded Au–SiO2 core–shell to assess the various biochemical parameters, including body weight, arthritic score analysis, hind paw volume, organ indices measurement, histological analysis pro-inflammatory cytokines, and anti-serum antibody analysis. The obtained results have proven that SiO2–Au develop a core–shell skin structure and each with its unique SA loading might act as a potential anti-inflammatory agent, which can be effectively used to treat collagen-induced arthritis compared to Au–SiO2 and SA. Therefore, SA loaded Au–SiO2 core–shell nanomaterials might employ as an interesting candidate in future arthritis applications.

The current investigation employed rosuvastatin for evaluation as an antiarthritic agent by in vitro and in vivo studies. In vitro studies comprised egg albumin and bovine serum albumin protein denaturation assays along with membrane stabilization assays, while in vivo studies comprised formaldehyde and complete Freund’s adjuvant (CFA)-provoked arthritis. The antioxidant potential was estimated via DPPH free radical scavenging and ferric reducing assays. Rosuvastatin significantly inhibited heat-provoked protein denaturation of egg albumin and bovine serum in a concentration-dependent way with the highest inhibition of 1225 ± 9.83 and 82.80 ± 4.03 at 6400 μg/mL. The percentage protection of the RBC membrane from hypotonicity-prompted lysis was found to be 80.67 ± 2.7. Rosuvastatin promisingly subdued formaldehyde-provoked arthritis, with maximum reduction (65.47%) of the paw volume being observed at a dose of 40 mg/kg. Rosuvastatin also significantly (p < 0.001) attenuated arthritis induced by CFA injection by reducing the paw volume and arthritic index. The reduction in the body weight due to CFA injection was also preserved by rosuvastatin treatment. Hematological and biochemical changes due to arthritis induction by CFA injection were also maintained near normal values by rosuvastatin. The histopathological and radiographic investigation also revealed the protective effect of rosuvastatin on preventing structural changes. Gene expression of IL-1β, TNF-α, and IL-6 was reduced, while IL-4 and IL-10 levels were elevated by rosuvastatin in comparison to those for the disease control group. Concentration-dependent antioxidant potential was shown by rosuvastatin. Thus, rosuvastatin possesses a notable antiarthritic potential as evidenced via in vitro and in vivo studies.

Phytol is a diterpene constituent of chlorophyll and has been shown to have several pharmacological properties, particularly in relation to the management of painful inflammatory diseases. Arthritis is one of the most common of these inflammatory diseases, mainly affecting the synovial membrane, cartilage, and bone in joints. Proinflammatory cytokines, such as TNF-α and IL-6, and the NFκB signaling pathway play a pivotal role in arthritis. However, as the mechanisms of action of phytol and its ability to reduce the levels of these cytokines are poorly understood, we decided to investigate its pharmacological effects using a mouse model of complete Freund's adjuvant (CFA)-induced arthritis. Our results showed that phytol was able to inhibit joint swelling and hyperalgesia throughout the whole treatment period. Moreover, phytol reduced myeloperoxidase (MPO) activity and proinflammatory cytokine release in synovial fluid and decreased IL-6 production as well as the COX-2 immunocontent in the spinal cord. It also downregulated the p38MAPK and NFκB signaling pathways. Therefore, our findings demonstrated that phytol can be an innovative antiarthritic agent due to its capacity to attenuate inflammatory reactions in joints and the spinal cord, mainly through the modulation of mediators that are key to the establishment of arthritic pain.

Objectives Evodiamine (Evo) possesses strong anti-inflammatory activity. In this study, we determine the antiarthritic effect of Evo. Methods Evo was administered to rats with adjuvant-induced arthritis (AA). We evaluated arthritis symptoms & histopathological changes and measured inflammatory cell infiltration, pro-inflammatory cytokine production and Th17 & Treg percentages in arthritic rats. Key findings Evo significantly improved the clinical signs of AA in rats, including decreases in paw swelling, the polyarthritis index and the number of swollen paw joints. Based on the histopathological analysis, Evo improved synovial inflammation and bone injury by inhibiting inflammatory cell infiltration, synoviocyte proliferation, pannus formation and cartilage erosion. Furthermore, the numbers of synovial CD3+ or CD68+ inflammatory cells were reduced, and the elevated levels of tumour necrosis factor-α, interleukin-1β (IL-1β) and IL-6 were restored to control levels by the Evo treatment. In addition, Evo therapy regulated the abnormal differentiation of Treg and Th17 cells, decreasing IL-17 production and increasing IL-10 levels. Finally, Evo inhibited Stat3 phosphorylation and induced Stat5 phosphorylation in rats with AA. Conclusions Based on our results, Evo is a promising antiarthritic agent, potentially due to its inhibitory effect on synovial inflammation and regulatory effects on Treg and Th17 differentiation.

Background Ipomoea batatas L. Lam. is a functional food and belongs to family Convolvulaceae. It is used as an antiinflammatory, aphrodisiac, antiasthmatic, anticonvalescent, antitumor, antanemic and antidiabetic agent by local communities. This study has been planned to evaluate its antiinflammatory and antiarthritic potentials. Methods Dry powder of I. batatas tuber and roots were extracted with ethyl acetate (IPT-EA, IPR-EA) and methanol (IPT-M, IPR-M), respectively. These extracts were tested for total phenolic and flavonoid contents (TPC and TFC), HPLC finger printing, multidimensional in vitro and in vivo antioxidant potential and albumin denaturation inhibition. Carrageenan-induced paw edema, croton oil-induced ear and anal edema inhibition and Complete Freund’s Adjuvant (CFA)-induced antiarthritic assays were executed at a dose of 300 mg/kg body weight on Sprague-Dawley rats. Serum levels of interleukins IL-1β and IL-6 and nitric oxide (NO) were assessed to measure the inhibition of inflammation. Results Maximal TPC (319.81 ± 14.20 μg GAE/mg dry extract) and TFC (208.77 ± 9.09 μg QE/mg DE) were estimated in IPR-EA extract. IPT-EA and IPR-EA yielded the maximum amounts of rutin (7.3 ± 1.12 and 4.5 ± 0.55), caffeic acid (1.60 ± 0.25 and 2.17 ± 0.26) and myricetin (2.7 ± 0.14 and 1.01 ± 0.08 μg/mg DE), respectively in HPLC-DAD analysis. All extracts showed dose dependent response in in vitro antioxidant assays. Best inhibition (76.92 ± 3.07%) of albumin denaturation was shown by IPT-EA in comparison to ibuprofen (79.48 ± 4.71%). IPR-EA exhibited highest edema inhibition in models of carrageenan-induced paw edema (79.11 ± 5.47%) and croton oil-induced ear and anal edema (72.01 ± 7.80% and 70.80 ± 4.94%, respectively). Significant inhibition of CFA-induced arthritic edema and arthritic score were observed by IPR-EA as compared to ibuprofen. Suppression of pro-inflammatory cytokines (IL-1β, IL-6) and NO levels was shown by IPR-EA and IPT-EA, respectively. Conclusion These results depict that richness of polyphenols and phytoconstituents in I. batatas ameliorates oxidative stress and inflammation of acute and chronic nature. Dose dependent antioxidant potential and inhibition of inflammatory edema, pro-inflammatory cytokines and hematological, biochemical and histological changes prove I. batatas therapeutic potential as an antiinflammatory and antiarthritic agent. Graphical abstract Electronic supplementary material The online version of this article (10.1186/s12906-018-2279-5) contains supplementary material, which is available to authorized users.

Rheumatoid arthritis (RA) is a systemic autoimmune disease, characterized by the irreversible joint destruction resulted from the attack of inflammatory cells to the joints. Recent studies demonstrated that crocin is able to alleviate arthritis and suppress inflammatory responses, implying crocin as a potential promising antiarthritic agent. In this study, we confirmed the effect of crocin on RA and revealed its underlying mechanism by measuring lipopolysaccharides (LPS)-stimulated cytokine production in presence or absence of crocin. The effect of crocin was also tested in vivo using a mouse model of collagen-induced arthritis (CIA). It was found that crocin significantly repressed the LPS-induced expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in human fibroblast-like synoviocytes (FLS). We tested the effect of crocin on nuclear factor-kappa B (NF-κB) signaling and observed that cells pre-treated with 500 μM of crocin exhibited lower levels of LPS-induced p-IκBα, p-IκB kinase (IKK) α/β, and p65 expression than those of untreated cells. In addition, we found when cells were stimulated with IKKβ, crocin pre-treatment showed significantly inhibitory effect on the luciferase activity of IL-1β. In vivo results also showed that crocin treatment dramatically reduced plasma levels of TNF-α, IL-1β, and IL-6 in CIA mice. Crocin is efficient to suppress the productions of TNF-α, IL-6, and IL-1β by blocking NF-κB signal activation through its interaction with IKK, suggesting that crocin could be an efficient treatment for RA.

Available conventional drugs produce several side effects; thus, a potent herbal drug is urgently required for the management of rheumatoid arthritis. The present investigation was performed to evaluate the antiarthritic activity of butanol fraction of Punica granatum Linn. rind methanolic extract (PGBF) against Freund's complete adjuvant (FCA)-induced arthritis in rats. An acute toxicity study of butanol fraction was conducted, accompanied by a study of its antiarthritic activity. Chromatography (thin layer chromatography and high-performance thin layer chromatography) analyses were also conducted. Phytochemical screening of the fraction was performed to confirm the presence of phytoconstituents. For antiarthritic activity, the active butanol fraction was administered at doses of 50 and 75 mg/kg body weight. The antiarthritic activity was evaluated by using biophysical paramaters (arthritic score, body weight, paw volume and joint diameter) and hematological parameters [red blood cell (RBC) count, white blood cell (WBC) count, hemoglobin (Hb) concentration and erythrocyte sedimentation rate (ESR)]. Dexamethasone (5 mg/kg) was selected as the standard. Phytochemical screening of butanol fraction showed the presence of steroids, tannins, flavonoids, irioid glycosides, and phenolic compounds. Acute toxicity studies suggested that butanolic fraction was safe up to a dose of 500 mg/kg. The data regarding biophysical and hematological parameters clearly indicated that the butanol fraction at a 75 mg/kg dose showed a more significant effect (**P

RANKL and RANK are potential contributors of inflammatory cascade in human and animal model of arthritis. The current study aims to investigate the effect of N-(2-hydroxyphenyl)acetamide (NA-2) on regulation of RANKL pathway in collagen-induced arthritis (CIA) model in rats. CIA was induced using bovine type II collagen in female Wistar rats. The clinical parameters, level of pro-inflammatory and oxidative stress markers were measured to determine the progression of the disease. The mRNA level of RANKL and RANK and downstream mediators of inflammation i.e. c-fos, c-jun, NF-κB and Akt were analysed in spleen tissue using real-time PCR. Immunohistochemical analysis of iNOS, pAkt and c-Fos was also done in spleen tissue. Treatment with NA-2 and indomethacin showed increase in body weight and significant reduction in paw volume and arthritic score (p

Objective: The objective of this study was to evaluate the anti-inflammatory and antiarthritic potential of Parmelia perlata. Methods: The relative study is based on in vitro anti-inflammatory and antiarthritic activity using hydroalcoholic extract of P. perlata (HAEPP). The preliminary phytochemical tests showed the presence of various phytochemical compounds such as alkaloids, flavonoids, and glycosides since the lichen species of P. perlata has the folklore claim of anti-inflammatory activity, thus it was studied by human red blood cells membrane stabilization method, and arthritic activity was carried using protein denaturation method using diclofenac as a standard. Results: The results showed eminent anti-inflammatory and antiarthritic activity in a dose-dependent manner. The membrane stabilization showed the maximum effect at 78.54% at the concentration of 1000 μg/, and the protein denaturation was also found maximum at 1000 μg/ml concentration at 79.43%. Thus, our research states the potent anti-inflammatory activity and antiarthritic effect in P. perlata. Conclusion: The HEAPP has a potent anti-inflammatory activity and antiarthritic activity. A further study has to be conducted to establish the pharmacological evidence behind the compound and the mechanism of action of the HAEPP on the inhibition of the inflammation process.

Articular cartilage degeneration and inflammation are the hallmark of progressive arthritis and is the leading cause of disability in 10-15% of middle aged individuals across the world. Cartilage and synovium are mainly degraded by either enzymatic or non-enzymatic ways. Matrix metalloproteinases (MMPs), hyaluronidases (HAases) and aggrecanases are the enzymatic mediators and inflammatory cytokines and reactive oxygen species being non-enzymatic mediators. In addition, MMPs and HAases generated end-products act as inflammation inducers via CD44 and TLR-4 receptors involved NF-κB pathway. Although several drugs have been used to treat arthritis, numerous reports describe the side effects of these drugs that may turn fatal. On this account several medicinal plants and their isolated molecules have been involved in modern medicine strategies to fight against arthritis. In view of this, the present study investigated the antiarthritic potentiality of Crocin, a dietary colorant carotenoid isolated from stigma of Crocus sativus. Crocin effectively neutralized the augmented serum levels of enzymatic (MMP-13, MMP-3 and MMP-9 and HAases) and non-enzymatic (TNF-α, IL-1β, NF-κB, IL-6, COX-2, PGE(2) and ROS) inflammatory mediators. Further, Crocin re-established the arthritis altered antioxidant status of the system (GSH, SOD, CAT and GST). It also protected the bone resorption by inhibiting the elevated levels of bone joint exoglycosidases, cathepsin-D and tartrate resistant acid phosphatases. Taken together, Crocin revitalized the arthritis induced cartilage and bone deterioration along with inflammation and oxidative damage that could be accredited to its antioxidant nature. Thus, Crocin could be an effective antiarthritic agent which can equally nullify the arthritis associated secondary complication.

This paper describes the synthesis and characterization of a composite constituted by an antiarthritic agent (AA) intercalated into a layered double hydroxide (LDH) supported on magnesium ferrite. Core-shell nanocomposites were prepared by depositing Mg-Al-NO(3)-LDH on a MgFe(2)O(4) core prepared by calcination of a nonstoichiometric Mg-Fe-CO(3)-LDH. Intercalation of ibuprofen and glucuronate anions was performed by ion-exchange with nitrate ions. The structural characteristics of the obtained products were investigated by powder X-ray diffraction, element chemical analysis, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Morphologies of the nanocomposite particles were examined by scanning electron microscopy and transmission electron microscopy. The products were shown to intercalate substantial amounts of AA with enhanced thermal stabilities. Room-temperature magnetic measurements by vibrating sample magnetometry revealed that the products show soft ferromagnetic properties suitable for potential utilization in magnetic arthritis therapy.

Background The beneficial effects of avocado/soybean unsaponifiables (ASU) are known as an antiarthritic agent. This experimental study presents the effects of ASU on oxidant/antioxidant systems and the number of apoptotic neurons of hippocampal formation after ischemia and reperfusion. Methods Eighteen rats were divided into three equal groups: group I rats were used as controls; group II rats were fed with standard diet and group III rats were fed with standard diet plus ASU pills for 10 days. One day after electrocauterization of bilateral vertebral arteries for groups II and III, bilateral common carotid arteries were occluded for 30 min and then reperfused for 30 min. After these procedures, rats of all groups were sacrificed. The levels of malondialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in the left hippocampus. The number of apoptotic neurons was counted by Tunel method in histological samples of right hippocampus. Results MDA and NO levels increased in group II compared with group I rats ( p = 0.002, p = 0.015). In group III, MDA and NO levels decreased as compared to group II ( p = 0.041, p = 0.002). SOD and CAT activities increased in group III as compared to group II rats ( p = 0.002, p = 0.002). The number of apoptotic neurons was lower in group III as compared to group II rats. Conclusions The present findings suggest that ASU could decrease oxidative stress and apoptotic changes in ischemic rat hippocampus. Dietary supplementation of ASU may be beneficial to prevent or ameliorate ischemic cerebral vascular disease.

Phyllanthus amarus Schum. & Thonn. (P. amarus) has been reported to exhibit anti-inflammation and antiarthritis properties leading to our interest to examine its beneficial effect in osteoarthritis. Thus, this study aimed to explore the chondroprotective potential of P. amarus extract (PAE) and its major compounds, phyllanthin and hypophyllanthin, in a cartilage explant model. Various concentrations of P. amarus extract, phyllanthin and hypophyllanthin, were treated on porcine articular cartilage explants induced with 25 ng/ml of interleukin-1 beta (IL-1β). After 4 days of incubation, the culture medium was measured for the release of sulfate glycosaminoglycans (s-GAGs) and matrix metalloproteinase-2 (MMP-2) activity by DMMB binding assay and zymography, respectively. The explant tissues were analyzed for the remaining of uronic acid content by colorimetric assay and stained with safranin-O for investigation of proteoglycan content. Cell viability of this model was evaluated by lactate dehydrogenase (LDH) assay. Chondroprotective potential of PAE and the major components against IL-1β-induced cartilage explant degradation were revealed by the decreased s-GAGs level and MMP-2 activity in culture medium consistent with an increase in uronic acid and proteoglycan contents in the explants when compared to the IL-1β treatment. These results agreed with those of diacerein and sesamin which used as positive controls. In addition, better chondroprotective activities of P. amarus crude extracts than those of the purified components were disclosed in this study. Hence, this is a pioneering study presenting the chondroprotective potential of PAE which may augment its application for therapeutic use as an antiarthritic agent.

Despite a multitude of reports on anti-inflammatory properties of ginseng extracts or individual ginsenosides, data on antiarthritic effect of ginseng saponin preparation with mixed ginsenosides is limited. On the other hand, a combined therapy of safe and inexpensive plant-derived natural products such as ginsenosides can be considered as an alternative to treat arthritis. Our previousin vitrodata displayed a strong anti-inflammatory action of red ginseng saponin fraction-A (RGSF-A). We, herein, report a marked antiarthritic property of RGSF-A rich in ginsenoside Rb1, Rc, and Rb2. Collagen-induced arthritic (CIA) mice were treated with RGSF-A or methotrexate (MTX) for 5 weeks. Joint pathology, serum antibody production and leukocye activation, cytokine production in the circulation, lymph nodes, and joints were examined. RGSF-A markedly reduced severity of arthritis, cellular infiltration, and cartilage damage. It suppressed CD3+/CD69+, CD4+/CD25+, CD8+T-cell, CD19+, B220/CD23+B-cell, MHCII+/CD11c+, and Gr-1+/CD11b+cell activations. It further suppressed anti-CII- or anti-RF-IgG/IgM, TNF-α, IL-1β, IL-17, and IL-6 secretions but stimulated IL-10 levels in the serum, joint, or splenocyte. RGSF-A attenuated arthritis severity, modified leukocyte activations, and restored cytokine imbalances, suggesting that it can be considered as an antiarthritic agent with the capacity to ameliorate the immune and inflammatory responses in CIA mice.

In the present study, the biopotential of capsaicin (an active principle of capsicum) as a topical antiarthritic agent was studied in arthritic rats. Transfersomal vesicular system was employed for the topical administration of capsaicin in experimental rats. The characterization of prepared capsaicin-loaded transfersomes reveals their nano size (94 nm) with negative surface charge (-14.5 mV) and sufficient structural flexibility, which resulted in 60.34% entrapment efficacy, penetration across the biomembrane (220 µm) and 76.76% of drug release from vesicular system in 24 h in their intact form as evident from confocal laser scanning micrographic study. Results of transfersomal nanoformulation (capsaicin loaded, test) were compared with that of conventional gel formulation available in the market (Thermagel, standard), with an aim to assess the antiarthritic efficacy of our prepared capsaicin-loaded transfersomal formulation. In vivo antiarthritic activity study shows that our formulation possesses superior inhibitory activity than the marketed Thermagel formulation at the same dosage level, which could probably be due to the lesser permeability of Thermagel across the dermal barriers compared to our specially designed transfersomal delivery system. Moreover, the better tolerance of prepared vesicular formulation in biological system further enlightens the suitability of the transfersomal vesicle to be used as a novel carrier system for the topical administration of such highly irritant substance.

Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) nonspecifically inhibit cyclooxygenase-1 (COX-1), an enzyme critical to normal platelet function, and COX-2, which mediates inflammatory response mechanisms. Celecoxib, an antiarthritic agent that inhibits COX-2 but spares COX-1 at therapeutic doses, is expected to have minimal effects on platelet function. A double-blind, randomized, placebo-controlled study of 10 days' duration was conducted in 24 healthy adults to compare the effects on platelet function of a supratherapeutic dose of celecoxib (600 mg bid) with a standard dose of naproxen (500 mg bid), a conventional NSAID. Ex vivo platelet aggregation in response to standard agonists (collagen, arachidonate, or U46619 [a thromboxane A2 receptor agonist]), bleeding time, and serum thromboxane B2 (TxB2) level were measured. Unlike celecoxib or placebo, naproxen produced statistically significant reductions in platelet aggregation and serum TxB2 levels and increased bleeding time. The results indicate that even at supratherapeutic doses, celecoxib will not interfere with normal mechanisms of platelet aggregation and hemostasis, supporting the premise that celecoxib is COX-1 sparing relative to conventional NSAIDs.

Phyllanthus amarus has been proven to exhibit chondroprotection. Regarding the morphological similarities among Phyllanthus species, we were attracted to evaluate the chondroprotective potential of Phyllanthus species including P. amarus obtained from Chiang Mai and Phuket, Phyllanthus urinaria L., Phyllanthus urinaria subsp. chamaepeuce, Phyllanthus debilis, and Phyllanthus airy-shawii using interleukin-1β-induced degradation of cartilage explants. The ethanolic extracts of the plants were evaluated for major lignans, phyllanthin, and hypophyllanthin by HPLC and further measurements of the total contents of flavonoids and phenolic compounds along with the assays for antioxidant and anti-collagenase activities. The interleukin-1β-induced cartilage explant degradation was performed with/without the extracts at concentrations of 50–250 µg/mL. After 4–14 days of incubation, the medium was assayed for the level of sulfated glycosaminoglycans while the explants were measured for the remaining content of uronic acid. Proteoglycan intensity in the explants was determined by safranin O staining. Diacerein, the antiarthritic agent, was used as the positive control. Although the two major lignans were found in P. amarus from Chiang Mai, P. amarus from Phuket, and P. urinaria L. extracts, similar chondroprotective activities were observed in all Phyllanthus extracts. Total phenolic content and total flavonoid content of the extracts showed a correlation with antioxidation, whereas the total phenolic content correlated with anti-collagenase activity. Among the six extracts, P. airy-shawii showed the greatest antioxidant and collagenase inhibitory activities. The results revealed that chondroprotective activities of all of the extracts of Phyllanthus species might result from an additive or synergistic influence of some constituents of these plants, which could be considered for antiarthritic purposes.

The aim of this study was to investigate the effects of andrographolide on matrix metalloproteinases (MMP) 1, 3, and 13 and inducible nitric oxide synthase (iNOS) in human articular chondrocytes from osteoarthritic cartilage.Passaged chondrocytes were pretreated with or without andrographolide for 2 h, followed by coincubation with interleukin-1 beta (IL-1β) 1 ng/ml for 24 h. Expression levels of MMP-1, 3, and 13, tissue inhibitor of metalloproteinase-1 (TIMP-1), and iNOS were evaluated using real-time-quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blotting. Nitric oxide (NO) was analyzed using the Griess reaction assay. Involvement of nuclear factor kappa B (NF-κB) was assessed by Western blotting, transient transfection, and luciferase reporter assay.Andrographolide tested in these in vitro studies was found be an effective antiarthritic agent, as evidenced by potent inhibition of MMP-1, 3, and 13 and iNOS expression, as well as upregulation of TIMP-1 in IL-1β-stimulated human articular chondrocytes (p0.05). The mechanism of andrographolide's inhibitory effects was mediated by attenuating the activation of NF-κB in human chondrocytes in the presence of IL-1β.Andrographolide was a potent inhibitor of the production of inflammatory and catabolic mediators by chondrocytes, suggesting that this natural compound may merit consideration as a therapeutic agent for treating and preventing osteoarthritis.

Auranofin is a gold(I)-containing drug in clinical use as an antiarthritic agent. Recent studies showed that auranofin manifests interesting antiparasitic actions very likely arising from inhibition of parasitic enzymes involved in the control of the redox metabolism. Trypanothione reductase is a key enzyme of Leishmania infantum polyamine-dependent redox metabolism, and a validated target for antileishmanial drugs. As trypanothione reductase contains a dithiol motif at its active site and gold(I) compounds are known to be highly thiophilic, we explored whether auranofin might behave as an effective enzyme inhibitor and as a potential antileishmanial agent. Notably, enzymatic assays revealed that auranofin causes indeed a pronounced enzyme inhibition. To gain a deeper insight into the molecular basis of enzyme inhibition, crystals of the auranofin-bound enzyme, in the presence of NADPH, were prepared, and the X-ray crystal structure of the auranofin–trypanothione reductase–NADPH complex was solved at 3.5 A resolution. In spite of the rather low resolution, these data were of sufficient quality as to identify the presence of the gold center and of the thiosugar of auranofin, and to locate them within the overall protein structure. Gold binds to the two active site cysteine residues of TR, i.e. Cys52 and Cys57, while the thiosugar moiety of auranofin binds to the trypanothione binding site; thus auranofin appears to inhibit TR through a dual mechanism. Auranofin kills the promastigote stage of L. infantum at micromolar concentration; these findings will contribute to the design of new drugs against leishmaniasis.

The title compound 3-carboxyisoxazole 3 was synthesized by cycloaddition of carbethoxyformonitrile oxide to N-[4-(trifluoromethyl)phenyl]-3-pyrrolidino-2-butenamide (6) with spontaneous elimination of pyrrolidine followed by hydrolysis of the ethyl ester. Compound 3 was shown to be absorbed intact after oral administration to rats. Over 24 h, the compound was metabolized to yield plasma concentrations of the antiinflammatory agent 2-cyano-3-hydroxy-N-[4-(trifluoromethyl)phenyl]-2-butenamide (2), similar to those obtained following an equivalent dose of the established prodrug of 5-methyl-N-[4-(trifluoromethyl)phenyl]isoxazole-4-carboxamide (1).

Compound IX 207-887 is a novel antiarthritic agent which inhibits the release of interleukin-1 (IL-1) from human monocytes and mouse peritoneal macrophages in vitro at concentrations which are achieved therapeutically in human rheumatoid arthritis and in animal models of arthritis. In the present studies IL-1 activity in conditioned media, homogenates or lysates was monitored using four independent assay systems. Biologically active IL-1 was determined by, a) the induction of latent metalloproteinase-release from rabbit articular chondrocytes, which is relatively specific for IL-1 and b) by a sensitive thymocyte proliferation assay. Immunoreactive IL-1-beta was assayed by RIA and ELISA. In all test systems IX 207-887 significantly reduced both biologically active and immunoreactive IL-1 in culture media, whereas the levels of IL-1 in homogenates or lysates were either unaffected or only marginally reduced. The release of other monokines tested, such as interleukin-6 and tumour necrosis factor-alpha, and the secretion of lysozyme were only marginally influenced. IX 207-887 neither affected the adherence of human monocytes nor markedly inhibited IL-1 or IL-2-induced thymocyte proliferation. In the chondrocyte test no IL-1 antagonistic activity of IX 207-887 could be observed. All of these data indicate that IX 207-887 has the novel property of being an inhibitor of IL-1 release.

Electrospray ionisation (ESI) mass spectrometry was used to examine the reactions of the clinically used antiarthritic agent [Au(S2O3)2]3−, and AuPEt3Cl, a derivative of another clinically used agent auranofin, with human serum albumin (HSA) obtained from a human volunteer. Both compounds reacted readily with HSA to form complexes containing one or more covalently attached gold fragments. In the case of AuPEt3Cl, binding was accompanied by the loss of the chloride ligand, while for [Au(S2O3)2]3− the mass spectral data indicated binding of Au(S2O3) groups. Experiments performed using HSA with Cys34 blocked by reaction with iodoacetamide were consistent with reaction of both gold compounds with this amino acid. Separate blocking experiments using diethylpyrocarbonate and AuPEt3Cl also provided evidence for histidine residues acting as lower-affinity binding sites for this gold compound. ESI mass spectra of solutions containing [Au(S2O3)2]3− or [Au(CN)2]−, and HSA, provided evidence for the formation of protein complexes in which intact gold molecules were non-covalently bound. In the case of [Au(S2O3)2]3−, these non-covalent complexes proved to be transitory in nature. However, for [Au(CN)2]− a non-covalent complex containing a single gold molecule bound to HSA was found to be stable, and constituted the main adduct formed in solutions containing low-to-medium Au-to-HSA ratios. Evidence was also obtained for the formation of a covalent adduct in which a single Au(CN) moiety was bonded to Cys34 of the protein. AuPEt3Cl reacted to a much lower extent with HSA that had Cys34 modified by formation of a disulfide bond to added cysteine, than with unmodified HSA. This suggests that the extent of modification of the protein in vivo may have an important influence on the transport and bioavailability of gold antiarthritic drugs.

Objective: To evaluate the acute and chronic antiinflammatory properties of leaf extracts of Kalanchoe crenata in rats. Material and methods: The methylene chloride/methanol extract of K. crenata was extracted by using hexane, methylene chloride, ethyl acetate, and n-butanol. The antiinflammatory profile of these extracts was investigated on the basis of paw edema induced by carrageenan. The n-butanol fraction (most potent) was further assessed through acute inflammatory models induced by histamine, serotonin, and formalin. The chronic antiinflammatory and the ulcerogenic activities of the n-butanol fraction were also examined. Results: The oral administration of n-butanol fraction (600 mg/kg) caused a maximum inhibition of about 45% in paw edema induced by carrageenan. The n-butanol fraction also exhibited acute antiinflammatory activity on paw edema induced by histamine (47.51%), serotonin (54.71%), and formalin-(40.00%) . In the chronic inflammation model, this extract showed maximum inhibition of 61.26% on the ninth day of treatment. The ulcerogenic assessment showed that ulcer indices after oral treatment with n-butanol fraction were zero and 0.4±0.2, for the 300 and 600 mg/kg doses, respectively. Conclusion: On the basis of these findings, it may be inferred that K. crenata is an antiinflammatory and antiarthritic agent that blocks histamine and serotonin pathways. The results are in agreement with the traditional use of the plant in inflammatory conditions.

An in situ rat intestinal preparation was modified to include portal and jugular venous blood collection techniques as well as sampling from the intestinal lumen. Viability could be maintained for 3 h. The utility of the preparation was examined by studying the disposition of four model drugs, each with differing characteristics with respect to absorption and presystemic metabolism. Haloperidol (4-[4-(4-chlorophenyl)-4-hydroxy-1-piperidinyl]-1-(4-fluorophenyl)-1- butanone), a reference compound used for model development, disappeared from the intestinal lumen with a half-life of 14 +/- 3 min. When the antiarthritic agent, tolmetin sodium (sodium 1-methyl-5-(4-methylbenzoyl)-1H-pyrrole-2-acetate dihydrate), was studied in the preparation, it was rapidly absorbed (t1/2 for disappearance from the intestinal lumen = 8 min), achieved plasma concentrations comparable to in vivo data, and underwent little presystemic elimination. In contrast, fenoctimine sulfate (4-(diphenylmethyl)-1-[(octylimino)methyl]piperidine sulfate), an antisecretory compound, disappeared more slowly from the intestinal lumen (t1/2 = 60 min), was present in portal plasma, but was not detected in systemic plasma. Extensive hepatic first-pass elimination of fenoctimine was evident. Tolmetin glycine amide (N-([1-methyl-5-(4-methylbenzoyl)-1H-pyrrol-2-yl]acetyl)glycine), a tolmetin prodrug, disappeared from the intestinal lumen very slowly (t1/2 approximately 3 h) compared with the other agents tested. It was determined that this drug was being hydrolyzed presystemically to tolmetin by the intestinal mucosa and the liver. These results establish the utility of this intestinal preparation for studying drug absorption and presystemic elimination.

The 1H and 13C high-field n.m.r. spectra of auranofin in a variety of aqueous and non-aqueous solvents have been analysed and all peaks unambiguously assigned except those for the acetyl groups. Specific solvation and co-ordination shifts are discussed. The conformation in solution appears to resemble that in the crystal, with the glucopyranose ring in a chair form. Phosphorus-31 n.m.r. studies suggest that auranofin is relatively stable at pH 7 and 4, but not at pH 1.

Auranofin (1), a phosphine gold(I) thiolate antiarthritic agent effective on oral administration, was labelled separately with 195Au, 32P and 35S. 195Au-labelled auranofin 19 was made from H195AuCl4.3H20via the intermediate chloro(triethylphosphine)gold-195Au (18). Auranofin -35S (23) was prepared using thiourea-35S. The synthetic routes for 19 and 23 were similar to those used for unlabelled 1. However, auranofin-32p (28) was made by the novel, direct coupling of the 1: complex (2,3,4,6-tetraO-acetyl-l-thio-β-D-glucopyranosato-S)gold (27) with 32p(C2H5)3 (26) synthesized from 32PCl3 (24). The labelled compounds were used in pharmacokinetic, tissue distribution and metabolism studies.

A series of gold(I) coordination complexes including analogues of the antiarthritic agent auranofin 1 were evaluated for in vitro cytotoxic potency against both B16 melanoma cells and P388 leukemia cells and in vivo antitumor activity against P388 leukemia in mice. A number of the complexes showed potent cytotoxic activity in vitro and antitumor activity in vivo, with the phosphine-coordinated gold(I) thiosugar complexes demonstrating the greatest in vitro and in vivo activity. The data compiled for 63 complexes of the general structural formula LAuX provide the basis for the following observations: potent in vitro cytotoxic activity is observed for substituted (phosphine) gold complexes, lack of potency in vitro correlates well with lack of antitumor activity, potent cytotoxicity in vitro is not necessarily predictive of activity in vivo, in vivo antitumor activity is generally optimized by ligation of Au(I) with a substituted phosphine and a thiosugar.

SummaryThe leg or hock abnormality of zinc-deficient chicks fed isolated soybean protein-based diets has previously been shown to be largely prevented by any of the following supplements: zinc, histidine, histamine, or any of several antiarthritic agents (aspirin, cortisone, phenylbutazone or indomethacin). Only zinc corrected all signs of deficiency while the other agents alleviated only the leg deformity. To better understand the mechanisms involved, the present experiments tested the effects on the leg abnormality of zinc-deficient chicks of certain vasoactive agents, compounds affecting histamine metabolism, certain vitamins required for normal hock development, and certain additional drugs which are known to influence experimental or human arthritis. Zinc, histamine, and chloro-quine, an antiarthritic agent, were shown to alleviate the hock abnormality. The condition was not influenced by the dietary addition of the other vasoactive amines, serotonin, norepinephrine, and epinephrine, or by two vitami...

Auranofin, an oral chrysotherapeutic agent effective in the treatment of rheumatoid arthritis (RA), was found to be a potent, noncytotoxic inhibitor of IgG-RF immune complex-induced lysosomal enzyme release (LER) from human leukocytes. At a concentration of 1 microg Au/ml (5 microM), auranofin produced a marked reduction in beta-glucuronidase (100%), acid phosphatase (88%), and lysozyme (72%) release. In contrast, gold sodium thiosulfate (GST, an injectable gold compound) had no inhibitory activity on LER at equivalent gold concentrations (i.e., 1 microg Au/ml) and only modest activity (less than 36% inhibition) at concentrations as high as 40 microg Au/ml. The 50% inhibitory dose (LD50) of auranofin on LER was calculated to be 3-4 microM (0.6-0.8 microg Au/ml). Blood gold levels in auranofin-treated RA patients were found to be within the range required for in vitro inhibition of LER, and correlated with decreases in IgG, RF titers, and IgG-RF immune-complex formation in vitro. These results suggest that the therapeutic action of auranofin may be caused, at least in part, by inhibition of LER and/or decreases in immune-complex formation.

Auranofin (AF), an orally active, antiarthritic agent, modulates the functional activities of macrophages in vivo and in vitro . To better understand the molecular mechanism of action of auranofin with macrophages we have investigated its cellular association, intracellular distribution, and efflux with RAW 264.7 cells using auranofin radiolabeled within the triethylphosphine (Et 3 P)[ 3 H], the gold [ 195 Au] or the tetraacetylthioglucose (TATG)[ 14 C] moieties of the molecule. Evaluation of the effects of auranofin on RAW 264.7 cells demonstrates that (1) cellular association of this compound was concentration, time and temperature dependent; (2) cellular association of AF was inhibited by N -ethylmaleimide but not by 2,4-dinitrophenol and NaF; (3) cellular association and uptake of Au and Et 3 P into cells was reduced when the drug was preincubated with increasing concentrations of fetal calf serum and albumin; (4) no tetraacetylthioglucose from the auranofin molecule became cell associated whereas the Au and Et 3 P moieties were internalized and distributed between the nuclear, cytosolic and membrane fractions of cells; and (5) efflux of Au and Et 3 P from RAW 264.7 cells was time and temperature dependent. Based on these data we propose a model, a sequential ligand exchange process, that describes the molecular interactions of auranofin and possibly other gold compounds with these cells.

Auranofin (AF), at a concentration of 10 micrograms/ml, was found to be a potent inhibitor of ADP-, epinephrine-, or collagen-induced platelet aggregation utilizing platelet-rich plasma obtained from human blood. In contrast, aurothioglucose was less effective than AF in inhibiting epinephrine- or collagen- induced platelet aggregation. The inhibitory effect of AF was more evident on the second phase of aggregation. The inhibitory effect of AF was more evident on the second phase of aggregation and was a function of drug preincubation time. Compared to platelet-rich plasma, washed platelets were superior for detecting the inhibitory action of AF (greater than or equal to 0.1 microgram/ml) on ADP-induced platelet aggregation. This potent inhibitory action of AF on ADP-induced platelet aggregation was antagonized by dithioerythriol, a potent reducing agent. These results suggest that AF can inhibit both platelet release and aggregation mechanisms which may be relevant to its antiarthritic activity. Further studies are required to elucidate the cellular mechanism by which AF inhibits platelet aggregation.

A series of gold(I) coordination complexes including analogues of the antiarthritic agent auranofin 1 were evaluated for in vitro cytotoxic potency against both B16 melanoma cells and P388 leukemia cells and in vivo antitumor activity against P388 leukemia in mice. A number of the complexes showed potent cytotoxic activity in vitro and antitumor activity in vivo, with the phosphine-coordinated gold(I) thiosugar complexes demonstrating the greatest in vitro and in vivo activity. The data compiled for 63 complexes of the general structural formula LAuX provide the basis for the following observations: potent in vitro cytotoxic activity is observed for substituted (phosphine) gold complexes, lack of potency in vitro correlates well with lack of antitumor activity, potent cytotoxicity in vitro is not necessarily predictive of activity in vivo, in vivo antitumor activity is generally optimized by ligation of Au(I) with a substituted phosphine and a thiosugar.