Anti-Ionizing Radiation Effect of Selenium on Osteoporosis Model during Bone Repair Pro

Abstract

Selenium (Se) is an essential trace element for humans and animals, and several findings suggest that dietary Se intake may be necessary for bone health. Accumulating evidence indicates that Se compounds possess anticancer properties. Se is specifically incorporated into proteins in the form of selenocysteine and non-specifically incorporated as selenomethionine in place of methionine. This study evaluated protection by Se in the bone repair process in ovariectomized rats after irradiation. For such purpose, 80 ovariectomized female Sprague-Dawley rats were randomly divided into 4 experimental groups: ovariectomized (Ov), Ov/Se, Ov/irradiated (Irr) and Ov/ Se/Irr. A bone defect was created on the tibia of all animals 40 days after ovariectomy. Two days after surgery, only the Ov/Se and Ov/Se/Irr rats received 0.8 mg Se/kg. Three days after surgery, only the Ov/Irr and Ov/Se/Irr rats received 10 Gy of X-rays on the lower limb region. The animals were euthanized at 7, 15, 22 and 29 days after surgery to assess the repair process, which was evaluated by analysis of trabecular bone number (Masson Trichrome) and birefringence analysis (Picrosirius). It was possible to observe a delay in the bone repair process in the ovariectomized/irradiated group and similarity between the ovariectomized, Ov/ Se and Ov/Se/Irr groups. Our findings suggest that sodium selenite may influence a radioprotective effect in the bone repair of tibia of ovariectomized rats without toxicity.

Keywords

• radiotherapy
• osteoporosis
• selenium
• ovariectomy