Effects and mechanisms of glucosides of chaenomeles speciosa on collagen-induced arthritis in rats

Abstract

Effects of glucosides of chaenomeles speciosa (GCS)—a Chinese traditional herbal medicine (CTM) on inflammatory and immune responses and its mechanisms in collagen-induced arthritis (CIA) rat were studied. Hind paw volumes of rats were measured by volume meter; lymphocyte proliferation, interleukin-1, interleukin-2, TNF-α level was determined by 3-(4,5-2dimethylthiazal-2yl)2,5-diphenyltetrazoliumbromide (MTT) assay; cAMP level in synoviocytes was analyzed by competitive protein binding assay (CPBA). mRNA expression of Gi,, Gs, and TNF-α of synoviocytes in CIA rats was measured by RT-PCR and antibodies to collagen type II (CII) were determined by enzyme-linked immunosorbent assay (ELISA), respectively. There was a marked secondary inflammatory response in CIA model, which accompanied with the decrease of body weight and the weight of immune organs simultaneously. The administration of GCS (30, 60, 120 mg kg−1, ig×7 days) inhibited the inflammatory response and restored body weight and the weight of immune organs of CIA rats. Lymphocyte proliferation and IL-2 production of CIA rats increases, together with IL-1 and TNF-α in peritoneal macrophages and synoviocytes. The administration of GCS (30, 60, 120 mg kg−1, ig×7 days) reduced above changes significantly. GCS at the concentration of 0.5, 2.5, 12.5, 62.5, 125 mg l−1 increased cAMP level of synoviocytes, which decreased in CIA rats in vitro. At the same time, GCS inhibited mRNA expression of Gi, and TNF-α of synoviocytes and increased mRNA expression of Gs of synoviocytes in CIA rats. GCS had no effect on the concentration of antibodies to CII. GCS possesses anti-inflammatory and immunoregulatory actions and has a therapeutic effect on CIA rats due to G protein-AC-cAMP transmembrane signal transduction of synoviocytes, which play a crucial role in pathogenesis of this disease.