辛伐他汀改善辐射所致小鼠胸腺损伤的机制研究
发布时间：2018-10-08 20:47
【摘要】：研究目的： 放射疗法(Radiotherapy)是临床上常用的癌症治疗手段。放疗能够有效抑制肿瘤组织增生，导致肿瘤细胞死亡；但同时对正常组织也具有一定的损伤作用。基于放疗的抗癌疗法会产生急性(acute)、亚慢性(subchronic)和晚期慢性(late chronic)副作用，这些副作用包括促炎、促纤维化、促细胞死亡等反应，严重降低患者的生活质量。因此，使用药物手段干预辐射所致的应激反应，将是减轻放疗副作用和提高患者生活质量的有效治疗策略。他汀类药物（3-羟基-3-甲基戊二酸甲酰辅酶A还原酶抑制剂，3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors，statins），是一类广泛使用的降脂药。研究表明，他汀类药物除了降脂作用之外，还对细胞应激反应、细胞增殖和凋亡等具有多重作用（pleiotropic effects）。值得注意的是，文献报道他汀类药物对辐射所致正常组织损伤还具有潜在的保护作用，其作用机制未有定论。因此，本课题在动物、细胞水平探讨了辛伐他汀(Simvastatin, SMV)是否能够抑制辐射所致的小鼠胸腺细胞凋亡，并从Akt、Sirt-1、p53、bcl-2和DNA损伤修复酶PARP的表达方面进行了机制探索。 研究内容及结果： 1.辛伐他汀显著减轻辐射所致的小肠和骨髓损伤 健康雄性C57/BL6小鼠随机分为4组：对照组(Control)，辛伐他汀组(SMV)，辐射组(Radiation,4Gy)，辐射+SMV组(RS)。辛伐他汀组和辐射+SMV组辐射前给予20mg/kg/d的辛伐他汀，连续灌胃14天。辐射组和辐射+SMV组小鼠4Gy γ-60Co辐射后第7天断颈处死，取各组小肠、骨髓组织进行HE、TUNEL染色和Annexin V/PI凋亡检测。发现：辐射会严重损害小肠、骨髓的形态，使小肠绒毛长度减短、骨髓出现空泡，使小肠和骨髓的凋亡细胞增多；辛伐他汀预处理能够显著减轻这些损伤。 2.辛伐他汀显著抑制辐射所致小鼠胸腺的氧化应激和细胞凋亡 取辐射后7天的胸腺组织，进行超氧化物岐化酶(SOD)、丙二醛(MDA)水平检测，并使用TUNEL染色与透射电镜(TEM)观察胸腺组织凋亡情况。发现：辛伐他汀预处理显著抑制辐射所致小鼠胸腺的氧化应激和细胞凋亡。 3.辛伐他汀抑制辐射所致小鼠胸腺细胞凋亡的机制 选取三个时间点，取辐射后1天、3天、7天的胸腺组织，提取胸腺组织蛋白，用Western blotting (WB)方法对小鼠胸腺组织内Akt、Sirt-1、p53和bcl-2蛋白以及DNA修复相关酶PARP的表达进行检测。发现：辛伐他汀对辐射小鼠胸腺细胞凋亡的保护作用与Akt/bcl-2通路相关。 4.辛伐他汀显著抑制体外培养胸腺细胞的凋亡 分离提取胸腺细胞并进行体外培养，随机分为4组：对照组(Control)，辛伐他汀组(SMV)，，辐射组(Radiation,8Gy)，辐射+SMV组(RS)。选择辛伐他汀浓度为20μM，辐射剂量为8Gy γ-60Co辐射。选取1h、6h和24h三个时间点，使用Annexin V/PI凋亡分析法对胸腺细胞凋亡情况进行检测。发现：辛伐他汀可显著抑制辐射所致体外培养胸腺细胞的凋亡。 5.辛伐他汀抑制辐射所致体外培养胸腺细胞凋亡的机制 胸腺细胞辐射后1h、6h和24h，提取胸腺细胞蛋白，用WB对胸腺细胞内Akt、Sirt-1、p53、bcl-2和PARP的表达进行检测。发现：辛伐他汀对辐射所致体外培养胸腺细胞凋亡的保护作用与Akt/bcl-2通路相关。 结论：辛伐他汀能够显著减轻辐射所致小鼠的小肠、骨髓和胸腺损伤；辛伐他汀能够显著改善辐射所致胸腺细胞的凋亡，机制涉及Akt/bcl-2信号通路。
[Abstract]:Purpose of the study: Radiation therapy (Radioththerapy) is a clinically common treatment for cancer Radiotherapy can effectively inhibit the proliferation of tumor tissue and cause tumor cell death, but also has certain damage to normal tissues at the same time. Anti-cancer therapy based on radiotherapy can produce acute (acute), subchronic and late chronic side effects, including pro-inflammatory, pro-fibrosis, cell death, etc., severely reducing the patient's life Therefore, the use of drug means to interfere with the stress response caused by radiation will be an effective treatment to reduce the side effects of radiotherapy and improve the quality of life of the patient Strategy. Statins (3-hydroxy-3-methylpent-2 acid, coenzyme A reductase inhibitor, 3-hydroxy-3-methyl-glutayl-CoA reductase inhibitors, stats) are widely used. in addition to lipid-lowering effect, pastatin has multiple roles in cell stress response, cell proliferation and apoptosis, in addition to lipid-lowering effect. (s). It is worth noting that the literature reports that statin drugs have a potential protective effect on normal tissue damage caused by radiation, and the mechanism of action has not been Objective: To investigate whether Simvastatin (Simvastatin) could inhibit the apoptosis of thymocytes induced by radiation in animals and cells, and the mechanisms of the expression of Akt, Sirt-1, p53, bcl-2 and DNA damage repair enzyme PARP were discussed. Exploration and research Content and results: 1. Simvastatin significantly reduced radiation The small intestine and bone marrow damaged healthy male C57/ BL6 mice were randomly divided into four groups: control group (control group), simvastatin group (control group), radiation group (Radiation, 4Gy). Radiation + Alarm Group (RS). Simvastatin and Radiation + Treatment Group Radiation before radiation dose of 20mg/ kg/ day Cuvastatin was administered continuously for 14 days. The radiation group and the irradiation group were sacrificed at the 7th day after irradiation with 4Gy Et-60Co radiation in the radiation group and the irradiated group. The small intestine and bone marrow tissues of each group were used for HE staining and Anne staining. xin V/ PI apoptosis detection. It was found that radiation could seriously damage the morphology of small intestine and bone marrow, shorten the length of small intestinal villi, vacuoles in the bone marrow, increase the number of apoptotic cells in the small intestine and bone marrow, and pre-place simvastatin. that can significantly reduce these damage. Simvastatin significantly inhibits radiation. The oxidative stress and apoptosis of thymocytes in mice were detected by SOD and MDA in 7 days after irradiation. The apoptosis of thymocytes was observed by electron microscopy (TEM). Oxidative stress and apoptosis of thymocytes induced by injection. Simvastatin inhibited thymocyte apoptosis in mice induced by radiation, three time points were selected, the thymus tissue was extracted for 1 day, 3 days and 7 days after radiation, the thymocyte protein was extracted, and Western blotting was used. Effects of WB method on Akt, Sirt-1, p53 and bcl-2 in mouse thymocytes Detection of the expression of protein and DNA repair-related enzyme PARP. Protective effect of apoptosis and Akt/ bcl-2 pathway 4. Simvastatin significantly inhibited the apoptosis of thymocytes in vitro and extracted thymocytes and cultured in vitro, randomly divided into 4 groups: control group (control group), simvastatin group (control group), spokes. Radiography (8Gy), Radiation + Response Group (RS). Selected The concentration of simvastatin was 20. m u.M, and the radiation dose was 8Gy LW-60Co radiation. Apoptosis of thymocytes by Annexin V/ PI apoptosis analysis method It was found that simvastatin could significantly inhibit the proliferation of thymocytes in vitro induced by radiation. Apoptosis of thymocytes. 5. Simvastatin inhibits the proliferation of thymocytes induced by radiation, 1h, 6h, and 24h after radiation of thymocytes, extracts thymocyte proteins, and uses WB to treat thymocytes. The expression of Akt, Sirt-1, p53, bcl-2 and PARP in cells was detected. Conclusion: Simvastatin can significantly reduce the damage of small intestine, bone marrow and thymus of mice induced by radiation.
【学位授予单位】：第二军医大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R965
本文编号：2258204
[Abstract]:Purpose of the study: Radiation therapy (Radioththerapy) is a clinically common treatment for cancer Radiotherapy can effectively inhibit the proliferation of tumor tissue and cause tumor cell death, but also has certain damage to normal tissues at the same time. Anti-cancer therapy based on radiotherapy can produce acute (acute), subchronic and late chronic side effects, including pro-inflammatory, pro-fibrosis, cell death, etc., severely reducing the patient's life Therefore, the use of drug means to interfere with the stress response caused by radiation will be an effective treatment to reduce the side effects of radiotherapy and improve the quality of life of the patient Strategy. Statins (3-hydroxy-3-methylpent-2 acid, coenzyme A reductase inhibitor, 3-hydroxy-3-methyl-glutayl-CoA reductase inhibitors, stats) are widely used. in addition to lipid-lowering effect, pastatin has multiple roles in cell stress response, cell proliferation and apoptosis, in addition to lipid-lowering effect. (s). It is worth noting that the literature reports that statin drugs have a potential protective effect on normal tissue damage caused by radiation, and the mechanism of action has not been Objective: To investigate whether Simvastatin (Simvastatin) could inhibit the apoptosis of thymocytes induced by radiation in animals and cells, and the mechanisms of the expression of Akt, Sirt-1, p53, bcl-2 and DNA damage repair enzyme PARP were discussed. Exploration and research Content and results: 1. Simvastatin significantly reduced radiation The small intestine and bone marrow damaged healthy male C57/ BL6 mice were randomly divided into four groups: control group (control group), simvastatin group (control group), radiation group (Radiation, 4Gy). Radiation + Alarm Group (RS). Simvastatin and Radiation + Treatment Group Radiation before radiation dose of 20mg/ kg/ day Cuvastatin was administered continuously for 14 days. The radiation group and the irradiation group were sacrificed at the 7th day after irradiation with 4Gy Et-60Co radiation in the radiation group and the irradiated group. The small intestine and bone marrow tissues of each group were used for HE staining and Anne staining. xin V/ PI apoptosis detection. It was found that radiation could seriously damage the morphology of small intestine and bone marrow, shorten the length of small intestinal villi, vacuoles in the bone marrow, increase the number of apoptotic cells in the small intestine and bone marrow, and pre-place simvastatin. that can significantly reduce these damage. Simvastatin significantly inhibits radiation. The oxidative stress and apoptosis of thymocytes in mice were detected by SOD and MDA in 7 days after irradiation. The apoptosis of thymocytes was observed by electron microscopy (TEM). Oxidative stress and apoptosis of thymocytes induced by injection. Simvastatin inhibited thymocyte apoptosis in mice induced by radiation, three time points were selected, the thymus tissue was extracted for 1 day, 3 days and 7 days after radiation, the thymocyte protein was extracted, and Western blotting was used. Effects of WB method on Akt, Sirt-1, p53 and bcl-2 in mouse thymocytes Detection of the expression of protein and DNA repair-related enzyme PARP. Protective effect of apoptosis and Akt/ bcl-2 pathway 4. Simvastatin significantly inhibited the apoptosis of thymocytes in vitro and extracted thymocytes and cultured in vitro, randomly divided into 4 groups: control group (control group), simvastatin group (control group), spokes. Radiography (8Gy), Radiation + Response Group (RS). Selected The concentration of simvastatin was 20. m u.M, and the radiation dose was 8Gy LW-60Co radiation. Apoptosis of thymocytes by Annexin V/ PI apoptosis analysis method It was found that simvastatin could significantly inhibit the proliferation of thymocytes in vitro induced by radiation. Apoptosis of thymocytes. 5. Simvastatin inhibits the proliferation of thymocytes induced by radiation, 1h, 6h, and 24h after radiation of thymocytes, extracts thymocyte proteins, and uses WB to treat thymocytes. The expression of Akt, Sirt-1, p53, bcl-2 and PARP in cells was detected. Conclusion: Simvastatin can significantly reduce the damage of small intestine, bone marrow and thymus of mice induced by radiation.
【学位授予单位】：第二军医大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R965
【参考文献】
相关期刊论文 前2条
1 周平坤;霍艳英;吴德昌;;辐射致癌效应与机制[J];辐射防护通讯;2007年01期
2 童新,孙志贤;辐射所致程序性细胞死亡的机制[J];国外医学(分子生物学分册);1995年03期
本文编号：2258204
本文链接：https://www.wllwen.com/yixuelunwen/yiyaoxuelunwen/2258204.html
最近更新
教材专著
