Radioprotective Effects of Granulocyte-Colony Stimulating Factor in the Jejunal Mucosa of BALB/c Mice

INTRODUCTION Radiation therapy, intended mainly for sterilization of cancer cells, is usually accompanied by adverse effects on the normal tissues surrounding the tumor mass (1, 2). They may lead to difficulties in continuing or completing the radiation therapy and ineffective treatment results. Especially in rectal cancer or uterine cervical cancer where the radiation fields include abdomen and pelvis, it is inevitable to radiation-induced gastrointestinal mucositis. There have been many efforts to reduce the radiation morbidity using physical methods or radiobiological methods such as radiation response modifier (2). Many of the traditional remedies for radiation injury can be discarded as they have been shown to be ineffective or even harmful (3). Granulocyte-colony stimulating factor (G-CSF) or granulocyte-macrophage colony stimulating factor (GM-CSF) is a hematopoietic growth factor and a cytokine that has been widely used to treat neutropenia caused by chemotherapy or radiotherapy. The efficacy of recombinant human hematopoietic growth factors in improving oral mucositis after chemotherapy or radiotherapy has been demonstrated in some clinical studies recently (3, 4, 5). But, the mechanisms of the beneficial effects and the most effective route for administration of G-CSF or GM-CSF on oral mucosal ulceration are unclear. This study was designated to determine whether G-CSF could modify the radiation injury of the jejunal mucosa in irradiated BALB/c mice.