Radioprotection by oral administration of Aegle marmelos (L.) Correa in vivo

The radioprotective effect of an extract of Aegle marmelos (L.) Correa (AME), family Rutaceae, was investigated in mice exposed to different doses of gamma-radiation. Mice were administered orally AME 250 mg/kg b.wt. orally daily for 5 consecutive days before exposure to 6, 7, 8, 9, 10, or 11 Gy of gamma-radiation. The animals were monitored daily up to 30 days after irradiation for the development of symptoms of radiation sickness or death. Treatment of mice with AME before irradiation reduced the symptoms of radiation sickness and delayed death compared to the irradiated controls given sterile physiological saline (SPS). AME provided protection against both gastrointestinal and hematopoietic toxicities. Reducing the administration schedule of AME to 1 or 3 consecutive days or increasing the schedule to 7 consecutive days was not as effective as 5 consecutive days of preradiation schedule. The administration of AME after irradiation was not effective, and no survivors could be reported 30 days after irradiation. The LD50/30 was found to be 8.1 Gy for the SPS + irradiation group and 9.7 Gy for the AME + irradiation group. The oral administration of AME resulted in an increase in radiation tolerance by 1.6 Gy, and the dose reduction factor was found to be 1.2. Preradiation treatment of mice with AME caused a significant depletion in lipid peroxidation followed by a significant elevation in glutathione concentration in the liver of mice 31 days after irradiation. The drug was nontoxic up to a dose of 6000 mg/kg b.wt., the highest drug dose that could be tested for acute toxicity.