Radioprotection of mice following garlic pretreatment.

Freshly prepared aqueous extract of garlic was tested in mice for its possible in vivo protective effect against gamma-radiation-induced chromosomal damage. In the same animals, the changes in the sulphydryl content and glutathione S-transferase activity were evaluated. Three doses of garlic extract [125, 250 and 500 mg kg-1 body weight (bw)] were administered orally for five consecutive days and the animals were exposed to 0.25, 0.5, 1.0 and 2.0 Gy gamma-radiation 2 h after the final feeding. The results of the bone marrow micronucleus test revealed that pretreatment with garlic extract was effective in reducing gamma-radiation-induced chromosomal damage. Against 0.25 Gy gamma-radiation, a high dose of 500 mg kg-1 bw garlic extract was required to significantly reduce the chromosomal damage. All the three doses of garlic extract were effective in exerting a protective effect against 0.5, 1.0 and 2.0 Gy gamma-radiation. However a dose-related effect was observed only against 2.0 Gy. The sulphydryl content and glutathione S-transferase activity registered a significant increase after either pretreatment with garlic with extract or irradiation. In the garlic extract pretreated irradiated animals, a significant reduction was observed in the sulphydryl content and glutathione S-transferase activity.