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, antiviral, anti-arthritic, and immunomodulatory effects. Fucoidan also exhibited neuroprotective, radioprotective, and antiulcer properties.
In animal models, fucoidan exerts anti-inflammatory effects to protect against various organ injuries. Oral administration of fucoidan extracts also improved inflammatory pathology associated with acute colitis. Although a high molecular weight fucoidan did not improve outcomes in mice following intracerebral hemorrhage, it is suggested that low-molecular-weight fucoidans have increased therapeutic potential and should be evaluated for this purpose.
In humans, dietary fucoidan modulates platelet aggregation via anti-thrombotic effects. In overweight or obese adults, fucoidan administration over 3 months decreased diastolic blood pressure and low-density lipoprotein cholesterol concentrations, and increased insulin secretion. Fucoidan administration also decreased pro-viral load in a small group of patients with human T-lymphotropic virus type-1-associated neurological disease. The consumption of fucoisan for a 1-month period prior to seasonal influenza vaccination may boost antibody production after vaccination in immune-compromised elderly.
Preclinical data suggest that fucoidan can help relieve cyclophosphamide-induced intestinal mucosal injury by altering gut flora, resulting in reduced inflammation and increased expression of tight junction proteins. Oral ingestion of fucoidan in a small group of volunteers was found to improve mobilization of hematopoietic progenitor stem cells with high levels of CXCR4 expression. In advanced stage colorectal cancer patients receiving chemotherapy, fucoidan coadministration enabled patients to continue chemotherapy and regulated fatigue; fucoidan also reduced the levels of pro-inflammatory cytokines in another study of advanced cancer patients.