Evaluation of melatonin for modulation of apoptosis-related genes in irradiated cervical spinal cord

This study examined the role of melatonin to reduce radiation-induced apoptosis in rat's cervical spinal cord. A number of rats were divided into four groups: (1) control group; (2) group that was treated with intraperitonial injection of melatonin; (3) group that got melatonin 30 min prior to cervical spinal cord gamma irradiation at a dose of 22 Gy; and (4) group that was given an intraperitonial injection of vehicle and the spinal cord radiation. The expression of Bax and Bcl-2 was evaluated by real-time reverse transcription polymerase chain reaction. Radiation-induced apoptosis was preceded by an increase in Bax gene expression. There was no evidence of radiation-induced apoptosis in the spinal cord of melatonin-treated animals. These findings suggest that melatonin has protective effects against spinal cord radiation-induced apoptosis through regulation of Bcl-2 and Bax expression. Thus, one possible role of melatonin in prevention of spinal cord injury is to block radiation-induced apoptosis.

Keywords: melatonin, cervical spinal cord, apoptosis, low radiation, rats, gamma irradiation, gene expression, spinal cord injury