Silkworm powder containing manganese superoxide dismutase regulated the immunity and inhibited the growth of Hepatoma 22 cell in mice

The effects of SOD contained silkworm powder on immune regulation and inhibition against Hepatoma 22 tumor cells in vivo were investigated. The activity of natural killer cell (NK) and the ConA-stimulated spleen proliferation were measured. The results found that the SOD-contained silkworm powder caused an enhancement on NK cell activity, which implied this material modulated the immune system in mice in vivo. The NK cell activities of Hepatoma 22 tumor modeled mice treated with silkworm powder including SOD were increased significantly compared to a modeled control and silkworm powder without SOD, reaching 36.18%. In addition, the ConA-stimulated spleen proliferation of SOD treated mice was higher than that of the controls. The treatment of SOD contained silkworm powder presented 40.3% of average inhibition rate to Hepatoma 22 tumor, showing stronger inhibition against tumor. There were no significant difference in body weight between modeled control and SOD silkworm powder feeding in Hepatoma 22 tumor modeled mice, suggesting the SOD silkworm powder is safety as an inhibitant to tumor. In conclusion, these findings demonstrate that administration of silkworm powder containing SOD results in activation of NK cells and immunity, suggesting the silkworm powder containing SOD plays a positive role in tumor inhibition.