Progression Of Adjuvant-induced Arthritis Research Articles

Fisetin Attenuates Cartilage Destruction in Adjuvant-Induced Arthritis by Modulating Cartilage Cytokine Expression Correlated with Oxidative Status in the Early Phase in Experimental Animals

The present study was designed to evaluate the effect of Fisetin on the progression of adjuvant-induced arthritis in rats and explore the mechanisms underlying fisetin mediated immunomodulation. Adjuvant-induced arthritis (AIA) was induced by a single subcutaneous injection of Freund's complete adjuvant (FCA). AIA rats were treated with Fisetin daily via oral gavage, for a period of 28 days. Paw swelling changes were assessed and histopathological and radiographic analysis was conducted to evaluate the antiarthritic effect. Lipid peroxidation and antioxidant enzyme activities in the joint tissue homogenate were performed to observe the modulation of the antioxidant status along the expression of different pro-inflammatory cartilage cytokines, such as TNF-á and IL-6. Fisetin promotes both the antiarthritic and the antioxidant effect, as well as the suppression of lipid peroxidation. Fisetin significantly inhibited the development phase of arthritis, as supported by histopathological and radiographical observations, and reduced overexpression of cartilage cytokines. Fisetin not only suppressed the arthritic progression and tissue destruction, but it also demonstrated a pronounced anti-inflammatory and immunomodulatory action against the immunosuppressive properties of AIA and provided a superior effect against inflammation. Furthermore, fisetin therapy restored the BMD loss and acts as a potent antioxidant and immunomodulator, suggesting that oral administration can suppress arthritic progression in rats.

Anti-inflammation effect of methyl salicylate 2-O-β-D-lactoside on adjuvant induced-arthritis rats and lipopolysaccharide (LPS)-treated murine macrophages RAW264.7 cells.

Methyl salicylate 2-O-β-D-lactoside (MSL) is a derivative of natural salicylate isolated from Gaultheria yunnanensis (Franch.) Rehder, which is widely used for treating rheumatoid arthritis (RA), swelling and pain. The aim of the present study was to investigate the effect of MSL on the progression of adjuvant-induced arthritis (AIA) in rat in vivo and explore the anti-inflammatory effects and mechanism of MSL in lipopolysaccharide (LPS)-treated murine macrophages RAW264.7 cells in vitro. Our results showed that MSL significantly inhibited the arthritis progression in AIA rats, decreasing the right hind paw swelling and ankle diameter, attenuating histopathological changes and suppressing the plasma levels of TNF-α and IL-1β in AIA rats. Besides, MSL had potent anti-inflammatory effects on the LPS-activated RAW264.7. MSL dose-dependently inhibited the activity of COX-1, and COX-2. Moreover, MSL prominently inhibited LPS-induced activation of MAPK in RAW264.7 cells by blocking phosphorylation of p38 and ERK. Our study suggests that MSL may be effective in the treatment of inflammatory diseases by inhibiting the pro-inflammatory cytokine production and regulating the MAPK signal pathway.

Combination of coenzyme Q10 with methotrexate suppresses Freund's complete adjuvant-induced synovial inflammation with reduced hepatotoxicity in rats: Effect on oxidative stress and inflammation.

Methotrexate (MTX) is a cornerstone disease modifying anti-rheumatic drug. One of its major drawbacks is hepatotoxicity, resulting in poor compliance of therapy. Coenzyme Q10 (CoQ10) is an antioxidant and anti-inflammatory compound, possessing both anti-arthritic and hepatoprotective potential. The present study was carried out to evaluate the effect of CoQ10 (10mg/kg) alone and in combination with MTX (2mg/kg) on the progression of adjuvant-induced arthritis in rats, and to elucidate the potential properties of CoQ10 in ameliorating MTX-induced liver damage in rats. Rats were assigned to; normal, arthritic, MTX treated, CoQ10 treated or a combination of MTX and CoQ10. CoQ10 administration potentiated the antiarthritic effect of MTX. Moreover, the combination therapy was effective in attenuating the severity of MTX-induced liver damage displayed by the improvement in hepatospecific serum markers and confirmed by the histo-pathological evaluation. Additionally, it attenuated the hepatic oxidative stress and the intensity of inflammatory mediators associated with MTX administration as evident by the regulation of oxidant/anti-oxidant balance and the inhibitory effects on TNF-α and IL-6 levels. These results revealed that CoQ10 can serve as a useful adjuvant and promote the safe use of MTX in the management of arthritis, not only by potentiating the antiarthritic effect of MTX, but also by alleviating MTX-induced hepatocellular injury.

Clematichinenoside AR induces immunosuppression involving Treg cells in Peyer׳s patches of rats with adjuvant induced arthritis

Ethnopharmacological relevanceClematichinenoside AR (AR) has been defined as a major active ingredient of triterpenoid saponins extracted from Clematidis Radix et Rhizoma, which is a traditional Chinese herbal medicine that has long been used in the treatment of rheumatoid arthritis (RA). To further explore the mechanism of AR in the treatment of RA, we investigated whether its immunomodulatory effects are related to Treg-mediated suppression derived from Peyer׳s patches (PPs) in adjuvant induced arthritis (AIA) rat model. Materials and methodsAR (8, 16, 32mg/kg) was orally administered daily from Day 18 to Day 31 after immunization. The effect of AR on AIA rats was evaluated by hind paw swelling and histopathological examination. Percentages of CD4+CD25+Foxp3+ T regulatory cells were determined by flow cytometry. Levels of IL-10, TGF-β1, IL-17A and TNF-α were measured by ELISA. Expressions of Foxp3 and RORγ in synovium were detected using immunohistochemical analysis. ResultsAR treatment significantly reduced paw swelling of AIA rats, and histopathological analysis confirmed it could suppress severity of established arthritis. AR treatment upregulated the percentages of CD4+CD25+Foxp3+ Treg cells among CD4+ T cells in PPs lymphocytes, and increased the levels of IL-10 and TGF-β1 secreted from ConA-activated PPs lymphocytes, whereas decreased the levels of IL-17 A and TNF-α. Similar tendency of circulating CD4+CD25+Foxp3+ Treg cells percentages and serum cytokine levels were observed. Moreover, AR decreased the expression levels of Foxp3 and RORγ in joint synovial membrane. ConclusionsIn conclusion, these results suggested AR has a potent protective effect on the progression of AIA, probably by augmenting CD4+CD25+Foxp3+ Treg cells in PPs to induce immunosuppression, and modulating the balance between Treg cells and Th17 cells systemically. These findings may help to develop AR as a potent immunosuppressive agent for the treatment of RA.

Anti-arthritic and anti-inflammatory activity of combined pioglitazone and prednisolone on adjuvant-induced arthritis

The aim of the present study was to evaluate the effect of combined treatment of pioglitazone (PGZ) and prednisolone (PDL) on the progression of adjuvant-induced arthritis in rats. Adjuvant arthritis was induced by single intra-dermal injection of 0.1ml Freund's complete adjuvant (0.05% w/v Mycobacterium butyricum in mineral oil) into foot pads of left hind paws of Wistar rats of either sex. There were six experimental groups: Group I was healthy animals as control, Group II was arthritic animals without drug treatment, Group III was arthritic animals treated with a standard non-steroidal anti-inflammatory drug aspirin (100mg/kg), Group IV was arthritic animals received PGZ (10mg/kg) alone, Group V was arthritic animals received PDL (10mg/kg) alone, and Group VI was arthritic animals treated with a combined suspension of PGZ and PDL (20mg/kg). Drugs were administered daily orally at day 0 and continued upto 28th day after induction of arthritis. Induction of arthritis significantly increased hind paw volume (HPV), loss of body weight (BW), enhanced tibiotarsal joint thickness (TJT), and increased plasma tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 levels. Treatment with aspirin or combined suspension of PGZ and PDL in the arthritic animals produced significant reductions in HPV and TJT, normalized BW, and significantly decreased plasma levels of TNF-α and IL-6. These observations suggest that the combined administration of PGZ and PDL was effective in modulating the inflammatory response and suppress arthritis progression in experimental animal model. These findings may help to improve the treatment of rheumatoid arthritis.

Combination therapy of dexamethasone with epigallocatechin enhances tibiotarsal bone articulation and modulates oxidative status correlates with cartilage cytokines expression in the early phase of experimental arthritis

The inclusion of antioxidant for the treatment of arthritis, especially under the therapy with immunosuppressant, is motivated because antioxidant plays an essential role in disease progression and moreover, immunosuppressive treatment suffers redox homeostasis balance of the organism. The aim of the present study was to evaluate the enhancement of anti-arthritic effect of dexamethasone in combination with epigallocatechin on the progression of adjuvant-induced arthritis in rats. Adjuvant arthritic rats were treated with dexamethasone (0.2mg/kg), epigallocatechin (100mg/kg) and combination of dexamethasone (0.1mg/kg) with epigallocatechin (100mg/kg) daily for a period of 28 days. Paw swelling changes, estimation of serum albumin level, alteration of bone mineral density, histopathological, and radiographical analysis were assessed to evaluate the anti-arthritic effect. Lipid peroxidation and antioxidant enzyme activities in joint tissue homogenate were performed along with the expression of different pro-inflammatory cartilage cytokines like TNF-α and IL-6. Dexamethasone and epigallocatechin combination potentiated both the antiarthritic (decrease of hind paw volume) and the antioxidant effect (lipid peroxidation, superoxide dismutase, glutathione reductase and catalase). In combination with dexamethasone, epigallocatechin markedly potentiated the beneficial effect of dexamethasone which resulted in more significant increment of serum albumin and bone mineral density. Improvement of anti-arthritic effect of combination therapy was supported by histopathological, radiographical alterations, and attenuation of over-expression of cartilage cytokines. Epigallocatechin act as potent antioxidant and combined administration of dexamethasone with epigallocatechin increased the anti-arthritic efficacy of basal dexamethasone therapy and suppressed the development phase of arthritic progression in rats.

A Novel Combination of Methotrexate and Epigallocatechin Attenuates the Overexpression of Pro-inflammatory Cartilage Cytokines and Modulates Antioxidant Status in Adjuvant Arthritic Rats

The present study was designed to evaluate the combinatory effect of methotrexate (MTX) and epigallocatechin (EGCG) on the progression of adjuvant-induced arthritis in rats. Adjuvant arthritis (AA) was induced by a single intradermal injection of Freund's complete adjuvant. AA rats were treated with methotrexate (0.3 mg/kg) thrice a week, EGCG (100 mg/kg) daily, and combination of MTX and EGCG thrice a week for a period of 28 days. Paw swelling changes and histopathological and radiographic analysis was assessed to evaluate the antiarthritic effect. Lipid peroxidation and antioxidant enzyme activities in joint tissue homogenate were performed to observe the modulation of antioxidant status along the expression of different pro-inflammatory cartilage cytokines like TNF-α and IL-6. MTX and EGCG combination potentiated both the antiarthritic (decrease of hind paw volume) and the antioxidant effect (SOD, GSH, and catalase) as well as suppression of lipid peroxidation. Combination therapy of MTX and EGCG significantly inhibited the development phase of arthritis, which is supported by histopathological, radiographical, and attenuation of overexpression of cartilage cytokines. EGCG act as potent antioxidant and immunomodulator, suggesting that combined administration of MTX along with EGCG suppressed the development phase of arthritic progression in rats.

CTLA4-FasL fusion product suppresses proliferation of fibroblast-like synoviocytes and progression of adjuvant-induced arthritis in rats

Fibroblast-like synoviocytes (FLSs) contribute significantly to the pathogenesis of Rheumatoid arthritis (RA). Through introducing apoptosis inducer FasL to suppress the proliferation of arthritic FLSs may provide an efficient approach for treatment of RA. CTLA4-FasL, a fusion product integrating two inhibitory elements of CTLA4 (which can induce T cell anergy through blocking costimulatory signal) and FasL (which may upregulate Fas-mediated apoptosis in inflammatory synoviocytes) into one molecule, might be a desirable engineered derivative of soluble FasL which exerts severe side effects and poor activities. In present study, we investigated the possible effect of CTLA4-FasL protein on suppressing the proliferation of inflammatory FLSs and inflammation in experimental model of RA. The purified CTLA4-FasL protein exerted a significant proliferation-inhibition activity to activated arthritic FLSs through both unbounded free and membrane-anchorage manners. CTLA4-FasL gene delivery by recombinant adeno-associated virus (rAAV) vector in joint, provided more powerfully preventive effects than mature FasL on rat adjuvant-induced arthritis (AIA) as reflected in clinical signs and typically histological characters. Treatment with rAAV.CTLA4-FasL also significantly decreased the levels of key proinflammatory cytokines in AIA joints. Our observations indicate that CTLA4-FasL protein represents a significantly suppressive effect on inflammatory FLSs’ proliferation and CTLA4-FasL gene transfer profoundly suppresses AIA, implicating potential application for treatment of RA by local joint delivery of CTLA4-FasL.

Combined methotrexate and coenzyme Q₁₀ therapy in adjuvant-induced arthritis evaluated using parameters of inflammation and oxidative stress.

Rheumatoid arthritis is a common severe joint disease that affects all age groups, it is thus of great importance to develop new strategies for its treatment. The aim of the present study was to examine the combined effect of coenzyme Q₁₀ (CoQ₁₀) and methotrexate (MTX) on the progression of adjuvant-induced arthritis in rats. Adjuvant arthritis (AA) was induced by a single intradermal injection of heat-inactivated Mycobacterium butyricum in incomplete Freund's adjuvant. The experiments included healthy animals, arthritic animals not treated, arthritic animals treated with CoQ₁₀, with methotrexate, and with a combination of CoQ₁₀ and methotrexate. The two latter groups received a daily oral dose of 20 mg/kg b.w. of CoQ₁₀, either alone or with methotrexate in an oral dose of 0.3 mg/kg b.w. twice a week. We found that CoQ₁₀ potentiated both the antiarthritic (decrease of hind paw volume) and the antioxidant effect of methotrexate on the level of oxidation of proteins (suppression of protein carbonyl level in plasma) as well as lipoperoxidation (suppression of levels of HNE-adducts and MDA-adducts to plasma proteins). The same effect was observed for plasmatic levels of CoQ₉ and IL-1α, and partially also for γ-glutamyltransferase activity assessed in joints and spleen. Moreover, the combination therapy improved the functionality of peripheral blood neutrophils in AA, with a balancing effect on the immunosuppression caused by MTX monotherapy. In summary, combined administration of CoQ₁₀ and methotrexate suppressed arthritic progression in rats more effectively than did MTX alone. This finding may help improve treatment of rheumatoid arthritis.

Therapeutic effects of daphnetin on adjuvant-induced arthritic rats

Aim of this study Daphnetin was regarded as the mark compound for quality control of Zushima-Pian, a traditional Chinese medicine tablet for treating rheumatoid arthritis (RA). However, no in vivo study on the therapeutic effects of daphnetin for RA has been reported. Materials and methods The adjuvant arthritic (AA) rat model was developed to evaluate the anti-arthritic effects of daphnetin. After immunized with Freund’s complete adjuvant (FCA), the rats were treated with daphnetin (2.25 and 4.5 mg/kg) for three weeks. We determined the change of secondary paw swelling and the arthritis scores of these tested rats. The severity of arthritis in the knee joints was evaluated by histological assessment of cartilage destruction. The levels of IL-1, TNF-α and MIF in the serum were measured by ELISA. Results and conclusions Our results showed that daphnetin significantly reduced paw swelling and decreased the arthritis scores. The pathological examination demonstrated that articular cartilage degeneration with synovial hyperplasia and inflammatory cells infiltration in AA rats were suppressed by daphnetin. There was significant reduction in production of interleukin-1 (IL-1), tumor necrosis factor (TNF-α) and macrophage migration inhibitory factor (MIF) in serum of AA rats treated with daphnetin except the low dose group (2.25 mg/kg) on TNF-α. In conclusion, we demonstrates that daphnetin is highly effective on preventing and suppressing the development and progression of adjuvant-induced arthritis and provides direct evidences that daphnetin is one of the active principle of Zushima-Pian for treating rheumatoid arthritis.

Use of local electroporation enhances methotrexate effects with minimum dose in adjuvant‐induced arthritis

To investigate the effects of electrical pulses on the ability of methotrexate (MTX) to attenuate inflammation and subsequent joint destruction in rats with adjuvant-induced arthritis (AIA). Rats in the experimental group received an intraperitoneal injection of MTX (0.125 mg/kg body weight), followed 30 minutes later by application of direct electrical pulses (50V, 8 Hz) to their left hind paws with an electroporation apparatus (M+/E+ group; n = 8). The procedure was repeated twice weekly for 3 weeks. Three control groups received the following treatments, respectively: MTX without electrical treatment (M+/E- group; n = 9), electrical treatment but no MTX (M-/E+ group; n = 10), or no electrical treatment and no MTX (M-/E- group; n = 9). Progression of AIA was monitored by joint swelling and radiologic and histologic changes in the ankle joint. Three weeks after injection of the adjuvant, and at the height of the arthritic reaction, the swelling and radiologic and histologic changes in the left hind paws in the M+/E+ rats were significantly reduced, as compared with changes observed in the control groups. These results demonstrate that application of electrical pulses in combination with use of systemic low-dose MTX can ameliorate local arthritic reactions. This response probably occurs because electrical stimulation promotes transient passage of MTX through pores in the cell membranes, with a resultant local increase in the concentration of the drug within the cells. These results point to a potential use of electrochemotherapy to increase the efficacy of MTX or other drugs in an arthritic joint that is refractory to treatment, without increasing the dose of the drug.

PECAM-1 and Leukosialin (CD43) Expression Correlate with Heightened Inflammation in Rat Adjuvant-Induced Arthritis

A hallmark of both adjuvant-induced arthritis (AIA) and rheumatoid arthritis is chronic joint inflammation characterized by ingress of leuko cytes into the inflamed synovial tissue. The timing of expression of adhesion molecules, which govern the ingress of leukocytes, is im portant in the orchestration of an inflammatory response. We examined the expression of vascular cell adhesion molecule-1 (VCAM-1), sialo adhesin, platelet and endothelial cell adhesion molecule-1 (PECAM-1), and leukosialin (CD43) in AIA, starting at adjuvant injection (day 0), through the peak of inflammation (day 18 postadjuvant injection), until day 54. VCAM-1 is constitutively expressed on the lining layer and ECs and its expression levels do not change throughout the progres sion of AIA. Sialoadhesin synovial tissue lining cell expression is decreased after adjuvant injection. In contrast, PECAM-1 expression is increased on synovial tissue lining cells on day 7 and is elevated through day 54 (peaking on day 54 with six-fold more cells expressing PECAM-1). PECAM-1 expression on endothelial cells peaks on day 7 with three-fold more cells expressing it, while on macrophages expression maximizes on day 25 with six-fold more cells expressing PECAM-1. CD43 expression is increased on synovial tissue lining cells, macrophages, neutrophils, and lymphocytes on days 18 and 25, before going back to basal levels. The increased expression of PECAM-1 and CD43 on leukocytes at the height of inflammation in AIA suggests important roles for these adhesion molecules in potentially binding their EC ligands resulting in leukocyte ingress into the synovial tissue.

Macrophage activation in rat models of inflammation and arthritis. Systemic activation precedes arthritis induction and progression.

The association between the induction and progression of adjuvant-induced arthritis (AA) and the development of synovial and systemic macrophage activation was assessed by studying the temporal development of these parameters in a rat model. Rats with AA developed significant edema of the uninjected hind leg beginning 10 days post-adjuvant injection, with progressive increases in edema continuing through day 17. Several parameters of macrophage activation, including the enhanced ability to secrete interleukin-1 and prostaglandin E2, kill tumor cells, accumulate fluorescent cyanine dyes, emigrate into the peritoneal cavity and synovium, and express Ia antigen, as well as the decreased ability to secrete superoxide anion, were associated temporally with the development of the arthritic lesion. In addition to the temporal association between macrophage activation and development of arthritis, a positive correlation between macrophage activation and arthritis induction was seen with the use of synthetic adjuvants at arthritogenic and nonarthritogenic doses. These data taken together suggest that induction and progression of AA in rats is associated with both systemic (blood, spleen, and peritoneal cavity) and local (synovium) macrophage activation.