title: Biological activities of alginate.
abstract: To gain insight into the structure-activity relationship of alginate, we examined the effect of alginates with varying molecular weights and M/G ratio on murine macrophage cell line, RAW264.7 cells in terms of induction of tumor necrosis factor-α (TNF-α) secretion. Among the alginates tested, alginate with the highest molecular weight (MW 38,000, M/G 2.24) showed the most potent TNF-α-inducing activity. Alginates having higher M/G ratio tended to show higher activity. These results suggest that molecular size and M/G ratio are important structural parameters influencing the TNF-α-inducing activity. Interestingly, enzymatic depolymerization of alginate with bacterial alginate lyase resulted in dramatic increase in the TNF-α-inducing activity. The higher activity of enzymatically digested alginate oligomers to induce nitric oxide production from RAW264.7 cells than alginate polymer was also observed. On the other hand, alginate polymer and oligomer showed nearly equal hydroxyl radical scavenging activities.
authors: Division of Biochemistry, Faculty of Fisheries, Nagasaki University, Nagasaki, Japan.
authors: Mikinori
authors: M
authors: Ueno
authors: Division of Biochemistry, Faculty of Fisheries, Nagasaki University, Nagasaki, Japan. Electronic address: t-oda@nagasaki-u.ac.jp.
authors: Tatsuya
authors: T
authors: Oda
mesh_terms: D000464:Alginates / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors; D009569:Nitric Oxide / Q000096:biosynthesis; D011133:Polysaccharide-Lyases / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D000464:Alginates; D000975:Antioxidants; D016207:Cytokines; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D020928:Mitogen-Activated Protein Kinases; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase
keywords: Alginate; Alginate oligomer; Guluronate; Macrophages; Mannuronate; Nitric oxide; TNF-α