Immunomodulatory effects of polysaccharide compounds in macrophages revealed by high resolution AFM.
Sargassum fusiforme is a kind of brown algae that has been widely consumed not only as food, but also as herbal medicine for thousands of years. The purpose of this study was to investigate the antioxidant activities and intestinal functions of polysaccharides extracted from S. fusiforme (SFP) in normal and cyclophosphamide-induced immunosuppressed mice. The experiment was performed on six groups of ICR mice, which treated with cyclophosphamide (CY, 200 mg/kg) or different dosages of SFP for 14 days. The results showed that administration of SFP was able to overcome the immunosuppression, and significantly increased the spleen index and antioxidant activities in mice (P<0.05). It also remarkably improved the numbers of jejunal intraepithelial lymphocytes (IELs) and goblet cells in immunosuppressed mice (P<0.05). For normal mice, SFP increased both thymus index and intestinal function parameters such as villus length/crypt depth ratio and intestinal IELs and goblet cells (P<0.05). The results suggested that SFP, possessing pronounced antioxidant activities, may play an important role in the improvement of intestinal function in mice. This might be one of the possible mechanisms of SFP for the immunomodulatory effects.