ABSTRACT
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.
Subject(s)
Arthritis, Experimental/drug therapy , Bones of Lower Extremity/drug effects , Cartilage/metabolism , Catechin/analogs & derivatives , Cytokines/metabolism , Dexamethasone/pharmacology , Joints/drug effects , Animals , Antioxidants/metabolism , Arthritis, Experimental/metabolism , Arthritis, Experimental/pathology , Arthritis, Experimental/physiopathology , Bone Density/drug effects , Bones of Lower Extremity/metabolism , Bones of Lower Extremity/pathology , Bones of Lower Extremity/physiopathology , Cartilage/drug effects , Cartilage/pathology , Catechin/pharmacology , Catechin/therapeutic use , Dexamethasone/therapeutic use , Drug Interactions , Gene Expression Regulation/drug effects , Hindlimb/drug effects , Hindlimb/pathology , Interleukin-1/metabolism , Joints/metabolism , Joints/pathology , Joints/physiopathology , Lipid Peroxidation/drug effects , Male , Oxidation-Reduction/drug effects , Oxidative Stress/drug effects , Rats , Rats, Sprague-Dawley , Serum Albumin/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
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.
