Recently, it has become clear that the intestine is not only a digestive organ that digests food but is also significantly involved in systemic health, such as obesity, immunity, arteriosclerosis, including mental disorders.
On a positive note, fucoidan is a cell wall polysaccharide found in various types of brown algae. Fucoidan is known to have multiple biological activities, including antioxidant, anticoagulant, antithrombotic, anti-inflammatory, antiviral, antilipidemic, antimetastatic, antidiabetic, and anticancer activities. In addition, fucoidan in food provides a small but constant amount of (FCSP) fucose-containing sulfated polysaccharides to the intestinal tract, reorganizing the composition of the commensal microbiota altered by FCSP and thus controlling intestinal inflammatory symptoms.
Although the bioactivity of fucoidan is well described, there is limited evidence suggesting its effects on gut microbiota and gut health. So, I would like to share the study “Fucoidan and Bowel health” by Jin-Young Yang et al., which summarizes recent research discussing their potential to alter commensal microbes and influence intestinal disease.
Fucoidan ingested with food can also enhance intestinal immune function through its immunomodulatory and anti-inflammatory effects. Fucoidan can also alleviate inflammation-related diseases, including inflammatory bowel disease. In this study, mice given fucoidan during antibiotic treatment showed reduced TNF-α, IL-1β, IL-6, and IL-10 in colonic tissue, suggesting the protective role of fucoidan in colonic health. In a study using the dextran sulfate sodium salt (DSS) mouse model of acute colitis, fucoidan extract-fed mice showed a significant reduction in diarrhea and fecal blood compared to untreated colitis mice.
In the same study, fucoidan extract decreased inflammatory cell infiltration and expression levels of inflammation-related cytokines, including TNF-α and IL-1β, in colonic tissue during DSS-induced inflammation. Involves the downregulation of mitogen-activated protein kinase (MAPK) and NF-κB signaling pathways in immune and structural cells, including epithelial cells, resulting in decreased proinflammatory cytokines and increased anti-inflammatory cytokines were shown.
Also, it is believed to be absorbed as short-chain fatty acids (SCFAs) by fucoidan fermentation by-products. Nutrients transported from fucoidan as an energy source can enhance intestinal barrier integrity and maintain intestinal homeostasis by interacting with various intestinal cells. (See Figure. 1)
Inflammatory bowel diseases (IBD), such as ulcerative colitis (UC) and Crohn’s disease (CD), is the most common intestinal disease. Especially, IBD is a disease whose incidence rate is increasing worldwide and is characterized by frequent intestinal inflammatory reactions of unknown causes. Two different fucoidan preforms, a fucoidan-polyphenol complex and depyrogenated fucoidan (DPF) can ameliorate DSS-induced acute colitis and reduce histopathological scores through the downregulation of proinflammatory cytokines.
Another intestinal disease that seriously threatens human health is colorectal cancer, the third most common cancer in the world. Emerging evidence suggests that fucoidan can be a promising anticancer agent. Although the efficacy of fucoidan uptake into intestinal epithelial cells depends on its molecular size, fucoidan extracted from Cladosiphon okamuranus is effective against colorectal cancer. It has been shown to increase survival in tumor model mice. Fucoidan can control cell viability and cell cycle by downregulating insulin-like growth factor (IRF)-I receptors via the Ras/Raf/ERK pathway. Fucoidan extracted from Sargassum cinereum inhibits cell proliferation by enhancing reactive oxygen species (ROS) generation, resulting in increased mitochondrial membrane permeability and apoptotic efficacy of Caco-2 cells.
Additionally, fucoidan is reported to inhibit the progression of lymphocyte tissue invasion by directly suppressing the activity of matrix metalloproteinases (MMPs). Recently, fucoidan was shown to have anticancer potential. As the investigation revealed inhibits the secretion of transforming growth factor-beta 1 (TGF-β1) and affects cancer cell viability through increased expression of C-type lectin-like receptor 2 (CLEC-2) in some gastric cancer cells. However, the role of fucoidan in the progression of intestinal disease must be clarified with further studies using higher animal models.
Source: Mar Drugs. 2021 Aug; 19 (8): 436. doi: 10.3390/md19080436