肿节风在放射性肺损伤中的防护作用

Effect of Sarcandra Glabra on Radiation-induced Lung Injury of Bama Minipigs

摘要:

目的: 探讨肿节风对⁶⁰COγ射线照射后在小型猪放射性肺损伤中的防护作用和机制. 方法: 60头雄性巴马小型猪随机分为正常组、照射组和肿节风组,在麻醉条件下对动物行右胸单次15 Gy的照射,正常组不予照射.肿节风组于放疗前1周开始经口腔给予肿节风配方颗粒溶液(30 mg·kg^-1),正常组和单照组给予等量的生理盐水,直至实验结束.在照射后4,8,12,24周,从3个组中分别随机取5头小型猪采集右肺组织,行羟脯氨酸测定检测肺组织中胶原含量;免疫印迹检测转化生长因子-β₁(TGF-β₁),基质金属蛋白酶-2(MMP-2)和MMP-9的蛋白表达;明胶酶谱法测定MMP-2和MMP-9的酶活性. 结果: 在照射后不同时间点,照射组中羟脯氨酸含量,TGF-β₁,MMP-2和MMP-9的蛋白表达,MMP-2,MMP-9的酶活性较正常组明显升高(P <0.05);与照射组比较,肿节风组的羟脯氨酸含量,TGF-β₁,MMP-2和MMP-9的蛋白表达,MMP-2,MMP-9的酶活性明显降低,差异具有统计学意义(P <0.05). 结论: 肿节风可通过降低TGF-β₁,MMP-2和MMP-9的蛋白表达和后者的酶活性,减缓放射性肺纤维化的发展,从而发挥放射防护作用.

Abstract:

Objective: To evaluate the effect of Sarcandra glabra on radiation-induced lung injury of right thoracic irradiation of Bama minipigs. Method: Sixty miniature pigs were randomly divided into the control group, the radiotherapy group and the S. glabra group. The pigs except the control group received a single right thoracic irradiation under anesthesia. The pigs in the S. glabra group received S. glabra formula granule solution at 30 mg·kg^-1 one week before radiotherapy, and the pigs in other groups received the same volume of normal saline..Five pigs were randomly selected and sacrificed from the three groups at week 4, 8, 12 and 24 post-irradiation. The collagen deposition was measured by Masson's trichrome and hydroxyproline detection. The protein expressions of transforming growth factor β₁ (TGF-β₁), matrix metalloproteinase 2 (MMP-2) and MMP-9 were detected by Western Blot. The activities of MMP-2 and MMP-9 were tested by Gelatin zymography. Result: At different weeks after irradiation, the protein expressions of TGF-β₁, MMP-2 and MMP-9, hydroxyproline content and gelatinase activities of MMP-2 and MMP-9 increased in the radiotherapy group as compare to the control group (P <0.05). The protein expressions of TGF-β₁, MMP-2 and MMP-9, hydroxyproline content and gelatinase activities of MMP-2 and MMP-9 decreased in the S. glabra group as compared with the radiotherapy group (P <0.05). Conclusion: S. glabra could slow down the development of radiation pulmonary fibrosis and have radiological protection by reducing the protein of TGF-β₁, MMP-2, MMP-9 and gelatinase activity.