
Sulfated alpha-L-fucan
Fucoidan is a sulfated polysaccharide found in the cell walls of many species of Brown seaweed. In vitro studies show that fucoidan has antitumor, antiangiogenic (2) (3) (4) (5) (6) (7), antiviral (15) (16), and immunomodulatory (17) effects. These effects are brought about by stimulating natural killer cells and by down regulating AP-I involved in cellular proliferation. Fucoidan also exhibited neuroprotective (11) (12), radioprotective (13), and antiulcer (14) properties but human data are lacking.
In other studies, fucoidan demonstrated anticoagulant (8) (9) and antithrombotic (10) activities, and can have additive effects when taken with anticoagulants.
Several species of Brown seaweed
Fucoidan has been shown to inhibit metastasis by preventing adhesion of tumor cells to the extracellular matrix. This is achieved by blocking the fibronectin cell-binding domain, necessary for formation of adhesion complexes (4). Fucoidan was also shown to induce apoptosis of human T-cell leukemia virus type I (HTLV-1) that causes Adult T-cell leukemia. It does so by inactivating NF-kB that regulates antiapoptotic proteins. It suppresses AP-I, a transcription factor involved in cellular proliferation and transformation (3). An vitro study showed that Fucoidan can suppress angiogenesis induced by Sarcoma 180 cells in mice (5). Fucoidan has immunomodulating effects and enhanced the activity of NK cells, which play a crucial role in mediating tumor cell death (2). The neuroprotective effects of fucoidan are attributed to its ability to suppress tumor necrosis factor-alpha (TNF-alpha)- and interferon-gamma (IFN-gamma)-induced NO production in C6 glioma cells (11) and to its antioxidative effects (12).
No adverse reactions have been reported from use of Fucoidan.
Raghavendran HR, Srinivasan P, Rekha S. Immunomodulatory activity of fucoidan against aspirin-induced gastric mucosal damage in rats. Int Immunopharmacol. 2011 Feb;11(2):157-63.
Bottom Line: Fucoidan has anticancer properties but it has not been studied in humans.
Fucoidan is a complex polysaccharide found in many species of Brown seaweed. It can slow blood clotting. Laboratory studies suggest that it can prevent growth of cancer cells and has antiviral, neuroprotective, and immunomodulatory effects. But there are no human data. Because of its anticoagulant property, fucoidan may increase the side effects of “blood thinning” drugs.
Theoretically, fucoidan may have additive effects with anticoagulants such as warfarin and heparin.
No adverse reactions have been reported from use of Fucoidan.