辐射暴露后HIF-1α介导的胰腺外分泌细胞能量代谢变化研究  

HIF-1α mediates energy metabolism of pancreatic exocrine cells after radiation

作　　者：刘显荣 彭秀达[1] 阳敦学 龙建武[1] 卢先州[1] Liu Xianrong;Peng Xiuda;Yang Dunxue;Long Jianwu;Lu Xianzhou(Department of General Surgery,Affiliated Nanhua Hospital,University of South China,Hengyang 421002,China)

机构地区：[1]南华大学附属南华医院肝胆外科,衡阳421002

出　　处：《中华放射医学与防护杂志》2019年第3期172-177,共6页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的阐明胰腺外分泌细胞辐射损伤后线粒体损伤情况、能量代谢变化及其可能机制。方法大鼠胰腺外分泌细胞AR42J分为照射组与空白对照组,照射组予单次6GyX射线照射,空白对照组未做处理。分别检测24、48、72、96h线粒体膜电位,24及48h三磷酸腺苷(ATP)产生量、乳酸产生量,24h活性氧(ROS)产生量;行免疫印迹试验检测辐照后24h应激及能量代谢相关因子HIF-1α、LDHA、PDH表达情况。大鼠按照随机数表法分为照射组和对照组。对照组给予12GyX射线照射,对照组予假照射(0Gy),每组4只。实验结果经动物体内实验进一步验证。结果与对照组相比,照射组细胞在接受辐照后24~96h,线粒体膜电位呈进行性下降(t=5.438~17.687,P<0.05),24及48hATP产生量下降(q=17.300、8.328,P<0.05),乳酸产生量升高(q=21.790、16.250,P<0.05),24hROS产生量升高(t=7.935,P<0.05);辐照促使缺氧诱导因子HIF-1α表达显著升高,介导糖酵解的关键因子LDHA显著升高,PDH表达下调,应用小干扰RNA技术沉默HIF-1α表达在一定程度上消除了辐照诱导的上述蛋白表达的变化。这些结果得到动物体内实验的验证。结论胰腺外分泌细胞在电离辐射应激下,通过上调HIF-1α表达,促使能量代谢方式发生转变,糖酵解途径加强,而经线粒体的有氧氧化受到抑制。Objective To study the radiation-induced mitochondrial damage and energy metabolic alteration in pancreatic exocrine cells,and to explore underlying mechanism.Methods Rat pancreatic exocrine cells (AR42 J) were divided into control group and experimental group irradiated with 6 Gy of X-rays.Mitochondrial membrane potential was detected at 24,48,72 and 96 h,the lactic acid and ATP production were detected at 24 h and 48 h,and reactive oxygen species (ROS) were detected at 24 h after irradiation.The expressions of energy metabolism related factors of HIF-1α,LDHA and PDH were detected by Western blot.The animal experiments were conducted to confirm the changes.According to random number table,eight rats were randomly divided into two groups with 4 rats in each.The irradiated group was exposed to 12 Gy of X-rays,while the control group sham-irradiated.Results Compared with the nonirradiated control group,the mitochondrial membrane potential (△Ψm) of the experimental group was progressively decreased at 24-96 h after irradiation (t=5.438-17.687,P<0.05).The ATP content in the experimental group decreased at 24 h and 48 h (q=17.300,8.328,P<0.05),the lactic acid increased (q=21.790,16.250,P<0.05),and the ROS level increased (t=7.935,P<0.05).The expressions of HIF-1α and LDHA were significantly increased,but PDH was reduced after radiation.Silencing HIF-1α by siRNA eliminated radiation-induced energy metabolic alteration.These changes were confirmed with animal experiments by locally irradiating rats.Conclusions The expression of HIF-1α is upregulated by irradiation,which leads to the change of energy metabolism as the enhancement of glycolysis pathway and the inhibition of aerobic oxidation of mitochondria in pancreatic exocrine cells.

关 键 词：辐射损伤 缺氧诱导因子 能量代谢 线粒体 

分 类 号：R818.74[医药卫生—放射医学] R576[医药卫生—临床医学]