immunomodulatory benefits of fucoidan in an animal model of complete freund's adjuvant-induced inflammation arthritis

Fucoidan, a complex sugar found mainly in brown seaweed, is known for its various health-related properties. this study investigated fucoidan extracted from the persian gulf seaweed sargassum tenerrimum, examining its effects on arthritis induced in wistar rats using complete freund s adjuvant. rats were given freund s adjuvant to trigger arthritis. the rats (10 per group) then received daily treatments of either a placebo, fucoidan at different doses (50, 100, 150 mg/kg), or prednisolone (10 mg/kg) from day 5 to day 23. fucoidan effectively lessened inflammation and eased the symptoms of arthritis in proportion to the dosage. immunohistochemical analysis revealed that fucoidan significantly decreased the levels of inflammatory substances il-1β and tnf-α in the arthritic rats joint tissue. moreover, fucoidan reduced multiple inflammatory markers, including myeloperoxidase, nitric oxide, malondialdehyde, and c-reactive protein, in a dose-dependent manner in joint tissue. fucoidan also lowered the activity of genes that promote inflammation (t-bet, rorγt), which led to a decrease in th1 and th17 cell development, while increasing the activity of gata3 and foxp3 genes, encouraging the development of th2 and treg cells. unlike prednisolone, fucoidan increased the levels of nrf2 and ho-1 in the rats paws. fucoidan from s. tenerrimum exhibits significant immune-regulating capabilities, suggesting it could be a valuable treatment option for managing complex inflammatory conditions like arthritis.