Evaluation of the Immunomodulatory Effects of Fucoidan Derived from Cladosiphon Okamuranus Tokida in Mice

Abstract

Okinawa mozuku (Cladosiphon okamuranus Tokida) is an edible seaweed classified as brown algae and is a native species of the Ryukyu Islands in Japan. In recent years, the genomic decoding of Okinawa mozuku has been completed. Previous studies on the anti-inflammatory, antiviral, and antitumor properties of Okinawa mozuku have suggested that it affects the regulation of cellular and humoral immunity. The aim of the present study was to examine the immunoregulatory effect of fucoidan derived from Okinawa mozuku in mice. A product containing fucoidan (purity, 88.3%; molecular weight, 49.8 kDa) was developed from Okinawa mozuku and tested for its immunoregulatory effects in mice. The experimental animals were 8-week-old female BALB/c mice to which fucoidan (0, 102.5, 205.0, 410.0, and 1025.0 mg/kg) was administered orally continuously for six weeks. Immune cell proliferation, cytokine production, macrophage phagocytosis, and serum antibody concentration were measured. We found that immune cell proliferation, interleukin (IL)-2, macrophage phagocytes, and serum antibodies (IgM, -G, -A) increased significantly, but IL-4, -5, and IgE decreased significantly. These results indicated that fucoidan modulated cellular and humoral immunity.

Keywords: Cladosiphon okamuranus; fucoidan; immune cell proliferation; immunomodulatory.

Figure 1

Effect of fucoidan on macrophage phagocytosis activity. The mice were administrated with fucoidan (FL, FM, FMH, FH) for 6 weeks. Peritoneal macrophage were isolated from mice and phagocytosis of fluorescence-labeled E. coli by macrophage was analyzed by flow cytometry. The macrophage to E. coli ratios were 25:1 and 50:1. All data were presented as mean ± SD (n = 10 mice/group). All experiments were performed in once per test condition. Different alphabets were significantly (p < 0.05).

Figure 2

Effect of fucoidan on serum IgG (a), IgM (b), IgA (c), and IgE (d) production. The mice were administrated with fucoidan (FL, FM, FMH, FH) for 6 weeks. The serum was analyzed using ELISA assays. All data were presented as mean ± SD (n = 10 mice/group). All the experiments were performed in once per test condition. Different alphabets were significantly different (p < 0.05).