The use of aqueous propolis extract against radiation-induced damage.

Whole body exposure to gamma radiation has been experimentally shown to exaggerate inflammatory responses and to enhance the release of mediators. A thirteen per cent aqueous extract of propolis (bee glue) was previously shown to have potent antiinflammatory activity. The present study was carried out to show whether the extract could influence the exaggerated inflammatory response in irradiated animals. Rats were exposed to acute (2 and 6 Gy) & fractionated (1 Gy/week) doses of gamma ionizing radiation. Treatment with the aqueous extract orally (5 ml/kg) before and after radiation exposure markedly reduced the exaggerated paw oedema response to carrageenan. In the acute phase of adjuvant-induced arthritis, exposure to ionizing radiation caused an increase in serum acid phosphatase level. Malondialdehyde concentration in plasma and superoxide dismutase activity in blood significantly increased. Treatment with aqueous propolis extract prior to irradiation reduced malondialdehyde concentration in plasma and normalized the serum acid phosphatase level. The extract stimulated the release of superoxide dismutase enzyme. Aqueous propolis extract could possibly be of therapeutic value in protecting against inflammatory responses induced by gamma radiation.