The analgesic and anti-rheumatic effects of Thladiantha dubia fruit crude polysaccharide fraction in mice and rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Thladiantha dubia has been used in Chinese manchu nationality folk medicine for treatment of various pains, such as rheumatic pain, lumbocrural pain, and dysmenorrhea. The aim of the present study was to evaluate the anti-rheumatic effect of Thladiantha dubia fruit crude polysaccharide (TF-P) fraction in rats.

MATERIALS AND METHODS: TF-P was evaluated in mice for analgesic activity using acetic acid-induced abdominal contractions test and for anti-inflammatory activity using xylene-induced ear oedema model. Moreover, rheumatoid arthritis (RA) was induced by injection of CFA into the subplantar surface of the hind paw of the male Wistar rats. Joint swelling was measured. In order to evaluate the effect of TF-P on disease progression, proinflammatory mediators (TNF-α and IL-2), and antioxidant indicators (SOD, MDA, and NO) were determined in rats induced by CFA. Pathologic changes of RA in rats were also observed under light microscope.

RESULTS AND CONCLUSIONS: In the present study, TF-P at the dose of 200mg/kg (according to the clinical traditional dosage) significantly reduced writhings and stretchings induced by the acetic acid in mice. TF-P significantly inhibited xylene-induced ear oedema in mice, compared with control group. TF-P significantly inhibited inoculated and non-inoculated joint swellings in rats induced by CFA. TF-P had no effect of body weight in rats. The histopathological analysis suggested that TF-P obviously alleviated the degree of RA rats. TF-P treated rats preserved a nearly normal histological architecture of the joint. Results of the present study confirm the use of Thladiantha dubia traditionally for the treatment of painful and inflammatory conditions. Those results suggest TF-P has protective and therapeutic effects on RA rats induced by CFA.