Macrophage-stimulating activities of newly isolated complex polysaccharides from Parachlorella kessleri strain KNK-A001

作者：Ueno Mikinori; Cho Kichul; Hirata Narumi; Yamashita Kenji; Yamaguchi Kenichi; Kim Daekyung^*; Oda Tatsuya^*

来源：International Journal of Biological Macromolecules, 2017, 104: 400-406.

DOI：10.1016/j.ijbiomac.2017.06.014

• Macrophages
• Nitric oxide
• Parachlorella kessleri
• Polysaccharides
• NF-kappa B
• TNF-alpha

Our previous studies demonstrated that the microalga Parachlorella kessleri (KNK-A001) has immunostimulatory activities, which were observed as an increase in natural killer (NK) cell activity in mice after intraperitoneal injection or as a protective effect on a virus-infected model shrimp after oral administration. In this study, we attempted to gain insight into the constituent substances of KNK-A001 that are responsible for the immunostimulatory activity. First, we obtained five polysaccharide fractions from KNK-A001 by DEAE anion exchange chromatography. Among the fractions, F5 showed the most potent induction of nitric oxide (NO) secretion in RAW264.7 cells, and both mRNA and protein expression levels of inducible NO synthase (iNOS) were increased in F5-treated RAW264.7 cells. A significant increase in the nuclear translocation of the p65 subunit of nuclear factor-kappa B (NF-kappa B) was observed in F5 treated RAW264.7 cells. F5 also induced the secretion of tumor necrosis factor (INF)-alpha in RAW264.7 cells. Analysis using mitogen-activated protein (MAP) kinase inhibitors suggested that c-Jun N-terminal kinase (JNK) and p38 MAP kinase were mainly involved in F5-induced NO and TNF-alpha productions. The compositional analysis of F5 identified the main constituents as galactose, glucose, galacturonic acid, and mannose. Gel-filtration analysis suggested that molecular mass of F5 was approximately 400 kDa. 2017 Elsevier B.V.

• 出版日期2017-11