Immunomodulating effect of Polysaccharide Krestin from Cariolus versicolor grown in Indonesia against Rheumatoid arthritis in Rat

Rheumatoid arthritis (RA) is a chronic inflammatory disease that can lead to joint destruction, deformity, and loss of function. The aim of this study is to investigate the therapeutic effect of polysaccharides krestin from Cariolus versicolor grown in Indonesia against complete Freund's adjuvant arthritis rat. Sixty-six male Wistar white rats (Rattus norvegicus) were induced by adjuvant arthritis. Samples were divided into 6 groups, 3 control (KP1, KP2, KP3) and 3 treatment groups (KP4, KP5, KP6). There were 3 different times of data collection: 1 week, 2 weeks, and 3 weeks after booster administration. Intragastric injection of polysaccharides krestin was given at a dose of 50 mg/kg body weight per day in all treatment groups. Flowcytometry blood tests were performed to examine the TGF-β1 level and T regulator percentage. The joint scale was observed using Elisa and histopathological analysis. The analysis of various arthritic assessment parameters used in this study revealed that polysaccharides krestin from Cariolus versicolor has a considerable effect in preventing the inflammation and severe damage in adjuvant arthritis rat's joint. The correlation between polysaccharides krestin-TGF-β1, levels-CD4+CD25+FoxP3+ Treg cells expression, and histopathological joint scale during the second weeks showed a strong correlation (p ≤0.05). These findings suggest that the administration of PSK from C. versicolor appears to be promising as immunomodulator and medication in chronic arthritis, therefore preclinical and clinical studies in human are highly recommended.