The effect of bone marrow mononuclear cells transplantation on brain injury after intracerebral hemorrhage in rats

Abstract

Objective To investigate the effect of intravenously transplanted bone marrow mononuclear cells(BMMNCs) on brain injury and inflammation after intracerebral hemorrhage(ICH) in rats. Methods Experimental ICH models were performed by stereotaxic injection collagenase Ⅳ into caudate putamen, rats that underwent ICH were randomly divided into four groups: sham operation group, ICH group, PBS group, BMMNC-treated group.The BMMNCs were injected intravenously into rats after ICH. The neurobehavioral function was evaluated on days 1, 3, 7, 14 by the modified neurological severity score, and the brain edema was examined by wet-dry weighting method on day 3 after cell transplantation. Immumofluorecence staining was used to identify the number of activation of microglia and infiltration of neutrophils in the brain after ICH. Results The neurological score in BMMNC-treated group on days 7, 14 was significantly improved compared with those in ICH group and PBS group(P<0.05). Compared to the ICH group((81.09±0.83)%) and PBS group((80.99±0.79)%), there was a significant decrease in the brain water content in BMMNC-treated group((78.62±0.97)%)(P<0.05). The number of activation of microglia and infiltration of neutrophils were both significantly lower in BMMNC-treated group ((55.8±22.1)/mm2, (49.6±12.9)/mm2) compared to ICH group and PBS group(respectively(125.0±20.7) /mm2, (86.8±13.6/mm2))(P<0.01). Conclusion Administration of BMMNCs can significantly reduce edema and improve neurologic function by inhibiting the activation of microglia and infiltration of neutrophils. Key words: Bone marrow mononuclear cells; Intracerebral hemorrhage; Edema; Microglia activation; Neutrophil infiltration