Phellinus baumii ethyl acetate extract alleviated collagen type II induced arthritis in DBA/1 mice

Abstract

Mushrooms have a long history of dietary benefits in Asia due to their health-promoting effects. Phellinus baumii, a wild mushroom, has been reported to have anti-platelet, anti-inflammatory, anti-obesity and free radical scavenging activities. However, its anti-rheumatoid arthritis (RA) property remains poorly understood. Hence, we investigated the protective effect of Phellinus baumii ethyl acetate extract (PBEAE) against bovine collagen type II induced arthritis (CIA) in DBA/1 mice. PBEAE (50 and 150 mg/kg) reduced the CIA score and leukocyte count in draining lymph nodes (DLNs) and inflamed joints. PBEAE also attenuated the expressions of CD3(+) (T cells), CD19(+) (B cells), CD4(+) (T-helper), CD8(+) (T-cytotoxic), MHC class II/CD11c(+) (antigen-presenting cells), double positives (B220(+)/CD23(+) and CD3(+)/CD69(+): early lymphocyte activation markers) and CD4(+)/CD25(+) (activated T-helper) leukocyte subpopulations in DLNs. Likewise, CD3(+) and Gr-1(+)CD11b(+) (neutrophil) counts in inflamed joints were also decreased. Furthermore, PBEAE reduced the serum levels of anti-collagen type immunoglobulin G, tumor necrosis factor-alpha and interleukin (IL)-1 beta and IL-6. Taken together, PBEAE impaired cellular recruitment to the inflamed joint and alleviated CIA, and thus could be considered as a potential agent against rheumatoid arthritis.