Immunomodulating Effects on Macrophage of Rhamnan Sulfate Extracted from Monostroma nitidum
The rhamnan sulfate extracted from green algae seaweed, Monostroma nitidum was characterized as activity in vitro culture assay with macrophages from mice. Rhamnan sulfate indicated that F-4-3 fraction enhanced glucose consumption, as well as the production of nitrogen dioxide and tumor necrosis factor(TNF). F-4-3 fraction was also augmented IL-1 secretion from those macrophages. Effects of the pretreatment of peritoneal macrophages with rhamnan sulfate F-4-3 fraction and several polysaccharides as relative standard on the production of H₂O₂ induced with unopsonized zymosan A were examined. Pretreatment with polysaccharides inhibited the zymosan A mediated H₂O₂ production by macrophages. The phorbol myristate acetate (PMA) mediated H₂O₂production was not affected by the pretreament. These result suggested that pretreatment of rhamnan sulfate interfered with the interaction of macrophages zymosan A. Rhamnan sulfate inhibited zymosan A mediated production of H₂O₂ by macrophages and F-4-3 fraction was also activator of macrophages.