骨髓间充质干细胞对大鼠急性放射性肝损伤修复的研究

Study on bone marrow mesenchymal stem cells in repairing of radiation induced acute liver injury of rats

目的探讨骨髓间充质干细胞（BMSCs）对大鼠急性放射性肝损伤的修复作用。方法雌性SD大鼠12只，肝右叶接受单次6MVX射线20Gy照射，建立急性放射性肝损伤模型；随机分成2组，干预组注射雄性大鼠BMSCs悬液，对照组注射等量生理盐水。4周后观察大鼠肝组织的病理形态学改变，采用原位杂交技术检测肝脏中性别决定基因Y（SRY）及免疫组织化学技术检测α-平滑肌肌动蛋白（α—SMA）的阳性表达。结果两组大鼠肝右叶组织中均可见汇管区炎性反应及肝实质细胞的损伤，但干预组的损伤程度比对照组轻。干预组大鼠肝右叶中检测到的SRY阳性细胞多于肝左叶（t=3．77，P〈0．05），Q—SMA的阳性表达率低于对照组（t=2．25，P〈0．05）。结论单次20Gy照射可以造成大鼠肝右叶急性放射性损伤；SRY阳性细胞可以被征募到大鼠的放射性肝损伤部位，在一定程度上可能减轻放射性肝纤维化的发生。

Objective To investigate the role of mesenchymal stem cells in the repair of radiation induced liver injury. Methods 12 female SD rats were irradiated with 20 Gy 6 MV X-rays on the right lobe of the liver, to establish the model of radiation induced liver injury. The rats were divided randomly into two groups as invention group and control group, and transplanted with 1 ml male mesenchymal suspension or 1 ml normal saline in 4 hours after radiotherapy. The morphological changes of liver were observed. The existence of sex determining gene Y（SRY）and the level of alpha-smooth muscle actin （α- SMA） were detected. Results Some injury of right lobe liver in two groups were observed, and the injury degree of right lobe liver in intervention group were lower than that of control group. The amount of SRY positive ceils in the right lobe liver of intervention group was higher than that in the left lobe liver（t = 3.77, P 〈 0.05 ）. The positive expression rate of α-SMA in right lobe liver of intervention group was lower than that of control group. Conclusions Acute radiation induced liver injury could lead BMSCs＇ homing in order to decrease the degree of liver fibrosis.