骨髓间充质干细胞移植治疗大鼠急性放射性肺损伤

背景：针对放射性肺损伤,临床上除了糖皮质激素及抗生素等对症处理外,尚缺乏有效的治疗手段。近年来研究表明,骨髓间充质干细胞表现出强大的组织修复能力。目的：观察骨髓间充质干细胞对大鼠放射性肺损伤的治疗作用,并初步探讨其作用机制。方法：体外分离、培养并鉴定雄性SD大鼠骨髓间充质干细胞。应用直线加速器照射60只雌性SD大鼠胸部,建立大鼠放射性肺损伤模型,随机分为骨髓间充质干细胞治疗组和生理盐水对照组。骨髓间充质干细胞治疗组经大鼠尾静脉输注骨髓间充质干细胞2×109L-1,生理盐水对照组注射等量生理盐水,分别于照射后1,2,4,6周时进行相关指标检测。结果与结论：照射后第1,2,4周时,骨髓间充质干细胞治疗组大鼠肺系数明显低于生理盐水对照组（P〈0.05）。镜下见骨髓间充质干细胞治疗组大鼠肺组织炎症渗出较少,肺泡、肺泡壁结构基本完整,纤维化程度等均明显轻于生理盐水对照组。照射2周时骨髓间充质干细胞治疗组血清转化生长因子β1、羟脯氨酸水平显著低于生理盐水对照组（P〈0.05）。照射2,4,6周时骨髓间充质干细胞治疗组肺组织超氧化物歧化酶活力显著高于生理盐水对照组（P〈0.05）,照射4,6周时骨髓间充质干细胞治疗组丙二醛含量显著低于生理盐水对照组（P〈0.05）。照射6周时骨髓间充质干细胞治疗组的肺表面活性物质B表达显著高于生理盐水对照组。PCR方法检测肺、肝脏、胰腺、肾脏等器官组织均有不同程度的Sry基因表达,尤以肺显著。结果表明骨髓间充质干细胞可以迁移到放射性损伤的肺组织,促进放射性肺损伤组织的修复,其治疗机制可能与抑制炎症反应、抗氧化、减轻肺组织纤维化等有关。

Bone marrow mesenchymal stem cell transplantation in the treatment of rat radiation-induced lung injury

BACKGROUND： Except for corticosteroids and antibiotics, there is no effective treatment for radiation-induced lung injury. Recent studies have shown that bone marrow mesenchymal stem cells appear to have strong tissue repair ability. OBJECTIVE： To observe the therapeutic effect of bone marrow mesenchymal stem cells on radiation-induced lung injury in rats, and then to preliminarily explore the mechanism of action. METHODS： Bone marrow mesenchymal stem cells from male Sprague-Dawley rats were isolated, cultured and identified in vitro. Sixty male Sprague-Dawley rats were subject to chest irradiation to establish radiation-induced lung injury models. Then, the model rats were randomly divided into treatment group and control group, respectively treated with tail vein injection of 2×109/L bone marrow mesenchymal stem cells and the same volume of normal saline. After 1, 2, 4, 6 weeks of irradiation, relevant parameters were detected. RESULTS AND CONCLUSION： After 1, 2, 4 weeks of irradiation, the lung coefficient was significantly lower in the treatment group than the control group （P 〈 0,05）. Under the microscope, less inflammatory exudation was from lung tissue in the treatment group, and the alveoli and alveolar wall structure were basically complete. The degree of fibrosis was significantly milder in the treatment group than the control group. Compared with the control group, the levels of serum transforming growth factor β1 and hydroxyproline were significantly lower in the treatment group （P 〈 0.05） at 2 weeks of irradiation, the activity of superoxide dismutase in lung tissue was significantly higher in the treatment group （P 〈 0.05） at 2, 4, 6 weeks of irradiation, the content of malondialdehyde was significantly lower in the treatment group （P 〈 0.05） at 4 and 6 weeks of irradiation, and the expression of pulmonary surfactant B was significantly higher in the treatment group at 6 weeks of irradiation. PCR results showed that Sty expressed in the lung, liver, pancreas, kidney