Antimutagenic effect of polysaccharide ginsan extracted from Panax ginseng

Ginsan is a polysaccharide extracted from the roots of Panax ginseng, and it has earlier been reported to have an immunostimulatory effect. In the present study, the frequency of micronucleated polychromatic erythrocytes (MNPCE) was assessed in the bone marrow of C57BL/6 male mice treated with ginsan [100, 200 or 300 mg/kg body weight (b.w.)] or amifostine (200 mg/kg b.w.) 30 min before as well as 15 min after 1.5 Gy of γ-irradiation. Ginsan and amifostine did not alter the frequency of MNPCE of control mice (P > 0.05), showing that they are non-mutagenic per se; γ-irradiation induced a statistically significant (P < 0.001) increase of MNPCE and decrease of PCE/NCE ratio (P < 0.001) compared to control group. However, ginsan applied 30 min before or 15 min after irradiation reduced MNPCE in a dose-dependent manner. Amifostine (200 mg/kg b.w.) did not reduce radiation-induced MNPCE, but stimulated erythropoiesis, when administered before irradiation. Based on the above results, radioprotective effect of ginsan can be partially attributed to reduction of radiation-induced genotoxicity.