肉碱棕榈酰转移酶1对^(60)Coγ射线照射大鼠小肠上皮细胞IEC-6增殖的影响及相关机制研究  

Mechanism of the influence of CPT1 on the proliferation of rat intestinal epithelial cells IEC-6 after^(60)Coγ-ray irradiation

作　　者：刘海翔 高玲[1] 李爽[1] 赵骅[1] 田梅[1] 刘青杰[1] Liu Haixiang;Gao Ling;Li Shuang;Zhao Hua;Tian Mei;Liu Qingjie(China CDC Key Laboratory of Radiological Protection and Nuclear Emergency,National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing 100088,China)

机构地区：[1]中国疾病预防控制中心辐射防护与核安全医学所,辐射防护与核应急中国疾病预防控制中心重点实验室,北京100088

出　　处：《中华放射医学与防护杂志》2022年第2期82-88,共7页Chinese Journal of Radiological Medicine and Protection

基　　金：国家自然科学基金(81573081,82003393)。

摘　　要：目的探索^(60)Coγ射线诱导大鼠小肠上皮细胞(IEC-6)中CPT1A和CPT1B蛋白表达变化,并进一步研究肉碱棕榈酰转移酶1(CPT1)变化对受照细胞增殖的影响及相关分子机制。方法IEC-6细胞经棕榈酸、血清饥饿以及血清饥饿联合棕榈酸处理后,给予0、5、10或15 Gy^(60)Coγ射线照射,照射后24 h收集细胞并提取蛋白,利用Western blot方法检测CPT1A和CPT1B蛋白的表达水平变化;ETO是CPT1的小分子抑制剂,利用克隆形成率实验和CCK-8实验分析ETO抑制CPT1对^(60)Coγ射线照射IEC-6细胞存活及增殖的影响;利用Western blot方法检测5 Gy^(60)Coγ射线照射ETO处理IEC-6细胞48 h后细胞外信号调节激酶1/2(ERK1/2)、c-Jun氨基末端激酶(JNK)蛋白表达及磷酸化水平变化。结果棕榈酸处理组中,CPT1A蛋白在15 Gyγ射线照射后表达量显著增加(t=-2.82,P<0.05)。血清饥饿处理组中,CPT1A蛋白在5、10和15 Gyγ射线照射后表达量明显升高(t=-3.28、-8.72、-8.67,P<0.05);血清饥饿联合棕榈酸处理组中,CPT1A蛋白在5、10和15 Gyγ射线照射后表达量显著增加(t=-10.69、-7.02、-8.23,P<0.05),CPT1B蛋白在照射10和15 Gyγ射线照射后表达量显著增加(t=-3.73、-5.05,P<0.05)。^(60)Coγ射线照射后,ETO处理组细胞存活率及相对增殖率明显低于对照组(t=5.46、13.22,P<0.05);ERK1/2蛋白表达水平及JNK磷酸化水平明显低于对照组(t=4.01、3.29、10.68、14.44,P<0.05)。结论CPT1通过促进增殖通路中ERK1/2蛋白的表达和JNK的激活,从而使得^(60)Coγ射线诱导IEC-6细胞损伤后的存活及增殖增加。Objective To investigate the changes of CPT1A and CPT1B protein expression in rat intestinal epithelial cells(IEC-6)after^(60)Coγ-ray irradiation,and the mechanism of the influence of carnitine palmitoyltransferase 1(CPT1)on the proliferation of irradiated IEC-6 cells.Methods IEC-6 cells were cultured in serum-normal medium or in serum-starved medium overnight,and pretreated with 20μmol/L palmitic acid(PA)before irradiation with 0,5,10,and 15 Gy.At 24 h after irradiation,the cellular protein was collected for the measurement of CPT1A and CPT1B proteins by Western blot.The influences of ETO,an inhibitor of CPT1,on the survival and proliferation of irradiated IEC-6 cells were analyzed by colony formation assay and CCK-8 assay.The protein expressions and phosphorylation levels of the extracellular signal-regulated kinase(ERK1/2)and c-Jun N-terminal kinase(JNK)in 5 Gy irradiated IEC-6 cells pre-treated with ETO were analyzed by Western blot at 48 h after radiation.Results When IEC-6 cells were cultured in serum-normal medium together with PA,the protein level of CPT1A was significantly increased after 15 Gy irradiation(t=-2.82,P<0.05).When IEC-6 cells were cultured in serum-starved medium,the protein level of CPT1A was significantly increased at 5,10,and 15 Gy(t=-3.28,-8.72,-8.67,P<0.05).When IEC-6 cells were cultured in serum-starved medium together with PA,the protein levels of CPT1A were significantly increased at 5,10 and 15 Gy(t=-10.69,-7.02,-8.23,P<0.05),the protein levels of CPT1B were significantly increased at 10 and 15 Gy(t=-3.73,-5.05,P<0.05).After irradiation,the survival and proliferation of IEC-6 cells in ETO group were significantly lower than those in control group(t=5.46,13.22,P<0.05),and the protein level of ERK1/2 and p-JNK in ETO group were significantly lower than those in control group(t=4.01,3.29,10.68,14.44,P<0.05).Conclusions CPT1 promoted radiation-induced IEC-6 injury cells survival and proliferation by enhancing the expression level of ERK1/2 protein and the activity of JNK.

关 键 词：放射肠损伤 增殖 细胞外信号调节激酶 C-JUN氨基末端激酶 肉碱棕榈酰转移酶1 

分 类 号：R818[医药卫生—放射医学]