Haemopoietic stem cells from rat fetal liver in the cytothesis of radiation brain injury

Abstract

Objective To study the cytothesis effects of haemopoietic stem cells （HSCs） from rat fetal liver on brain injury induced by radiation. Methods Twenty-four female SD rats were randomly divided into normal control group, model group and treatment group （n=8）. Total brain irradiation with 20 Gy X-ray was performed in the model group and the treatment group. Rats in the treatment group received infusion of HSCs from fetal liver （3×106 cells） 24 h, and 7, 14 and 21 d after irradiation, while rats in the model group and controls received infusion of saline at the same dosage. The serum of the rats was collected 12 h after infusion of HSCs each time; spectrophotometry was employed to detect the levels of malonaldehyde （MDA） and superoxide dismutase （SOD）; the contents of tumor necrosis factor α （TNFα）, interleukin （IL-1 and IL6） were measured by ELISA. Rats were sacrificed on the 28th d for assessing the pathological changes in brain tissue by HE staining and the mRNA level of Y chromosome by RT-PCR. Results Compared with that in the model group, the level of SOD in the treatment group was significantly higher, but the levels ofMDA, TNFα, IL-1 and IL6 were significantly lower in the treatment group 24 h, and 7, 14 and 21 d after the irradiation （P〈0.05）. The mRNA expression of Y chromosome was noted and apoptosis of Nissl bodies was also observed in the treatment group; the cerebral cortex in the treatment group was significantly thicker as compared with that in the model group （P〈0.05）; regenerative hippocampal neurons were observed in the treatment group. Conclusion HSCs from fetal liver can effectively repair the radiation brain injury. Key words: Stem cell; Radiation injury; Cytothesis