Induction of apoptosis in MCF-7 cells by ß-1,3-xylooligosaccharides prepared from Caulerpa lentillifera.

ß-1,3-Xylan was prepared from the green alga, Caulerpa lentillifera, and hydrolyzed to oligosaccharides by a mild acid treatment. The average degree of polymerization was about 5. The oligosaccharides reduced the number of viable human breast cancer MCF-7 cells in a dose-dependent manner, and induced chromatin condensation and degradation of poly ADP-ribose polymerase, indicating that they induced apoptosis in MCF-7 cells.

Immunostimulatory activity of polysaccharides isolated from Caulerpa lentillifera on macrophage cells.

Polysaccharides were extracted from Caulerpa lentillifera by treating with water and then purified by size-exclusion chromatography. The purified polysaccharides, termed SP1, were found to be sulfated xylogalactans with a molecular mass of more than 100 kDa. Adding SP1 to murine macrophage RAW 264.7 cells increased the production of nitric oxide (NO) in a dose-dependent manner. NO was found by immunoblotting and RT-PCR analyses to be synthesized by an inducible NO synthase. SP1 caused the degradation of IκB-α and the nuclear translocation of nuclear factor (NF)-κB subunit p65 in macrophage cells. SP1 also increased the phosphorylation of p38 mitogen-activated protein kinase (MAPK). These results demonstrate that SP1 activated macrophage cells via both the NF-κB and p38 MAPK signaling pathways. Moreover, SP1 increased the expression of various genes encoding cytokines, and the phagocytic activity of macrophage cells. These combined results show that SP1 immunostimulated the activity of macrophage cells.