In vivo assessment of anti-helminthic and anti-inflammatory effects of Fucoidan on Schistosoma mansoni immature stages

Schistosoma mansoni is a major cause of schistosomiasis, a neglected tropical disease that induces granulomatous inflammation, fibrosis, and liver damage. Fucoidan (FUC), a sulfated polysaccharide from brown seaweed, was evaluated for its anti-helminthic, anti-inflammatory, and antifibrotic effects against immature stages of S. mansoni in mice. Forty-eight CD-1 Swiss male albino mice were infected and allocated into six groups: infected untreated control, praziquantel-treated, and FUC-treated groups at 7, 21, 35, and 42 days post-infection. Treatment with FUC at 7, 21, and 35 dpi significantly reduced worm burden, granuloma size, fibrosis, and the expression of TNF-α, IL-1β, and iNOS in liver tissue. The strongest antipathological effects were observed with early-to-mid treatment, particularly FUC7, FUC21, and FUC35. In contrast, FUC42 showed weaker benefit, indicating that efficacy is timing-dependent. These findings suggest that FUC may be a promising candidate for early intervention in S. mansoni infection.