摘要全氟辛酸(PFOA)是全氟类有机化合物(PFCs)的一种,是一种新型的 持久性有机污染物,由于具有极强的化学稳定性和生物蓄积性,已在全球范围内广泛存在,对生物安全性构成威胁,成为全球性问题。本文旨在研究PFOA类化合物对鲫鱼淋巴细胞内凋亡信号通路的诱导机制,从而表明不同全氟化合物对鲫鱼的免疫毒性以及致毒机理。我们将鲫鱼解剖后提取出头肾,再从中提取出淋巴细胞,将其暴露在1μg/L、10μg/L、100μg/L、1000μg/L和10000μg/L的全氟辛酸、全氟十二酸、全氟十四酸中12小时,最后测定淋巴细胞的活性氧簇(ROS)、细胞生长抑制率(MTT)、线粒体膜电位(MMP)。结果显示,PFOA和十四酸的暴露浓度均为1μg/L、十二酸暴露浓度为1000μg/L会引起线粒体膜电位的显著下降(p<0。05),且表现出剂量-效应关系。十二酸和十四酸的暴露浓度均为1μg/L、PFOA暴露浓度为100μg/L会引起ROS水平的极显著升高(p<0。01),同时表现出剂量-效应关系,表明氧化应激的发生;同时细胞生长抑制率的测定结果显示出细胞凋亡上升,表现为极显著差异(p<0。01)。当PFOA暴露浓度为1μg/L时,细胞凋亡率达到8。47%,10000μg/L时则达到13。50%;当十二酸暴露浓度为1μg/L时,细胞凋亡率9。74%,10000μg/L达到12。82%;十四酸暴露浓度为1μg/L时,细胞凋亡率0。24%,10000μg/L时达到9。20%。通过对三种指标的检测发现对鲫鱼淋巴细胞影响最强的是全氟十二酸,其次为全氟辛酸,全氟十四酸最弱。该结果显示全氟类化合物的毒性与分子结构中所含C原子数和F原子数无必然联系。综上所述,PFOA类化合物可以诱导鲫鱼淋巴细胞发生凋亡,且与线粒体通路相关,进而对鲫鱼的免疫系统产生危害。72375
毕业论文关键词:全氟化合物;淋巴细胞;凋亡信号通路;毒效应
Abstract Perfluorooctanoic acid (PFOA) is a kind of perfluorinated compounds (PFCs)。 Tt is a new persistent organic pollutants with a strong chemical stability and biological chemicals。 It has been existed widely in the global scope。 It has posed a threat to biological safety and become a global problem。 The purpose of this paper is to study the apoptosis signaling pathways of carp lymphocytes induced by perfluorinatedoctylic acid compounds。 We extract the lymphocytes from carp kidney。 Then cells were exposed to PFOA, PFDoA, PFTeDA (1μg/L, 10μg/L, 100μg/L, 1000μg/L and 10000μg/L) for 12 h。 After exposure, ROS, MTT and mitochondrial membrane potential (MMP) in cells were detected。 Results showed that when the exposure concentration of PFOA and PFTeDA are 1μg/L, and that of PFDoA is 1000μg/L, MMP significantly decreased (p<0。05) in a dose-dependent manner。 ROS levels in cells also significantly increased with the exposure of PFDoA and PFTeDA (1μg/L) and PFOA (100μg /L)。 All the results indicate that oxidative stress happened in lymphocytes。 The experimental results of cell growth inhibition rate declared that apoptosis happened in cells。 When the exposure concentration of PFOA, PFDoA, PFTeDA was 1μg/L, the apoptosis percentages were 8。47%, 9。74% and 0。24%, respectively。 When the concentration reached 10000μg/L, apoptosis percentages increased to 13。50%, 12。82% and 9。20%, respectively。 Thus, in all three perfluorinatedoctylic acid compounds, PFDoA is the most toxic to carp lymphocytes。 Our results showed that the toxicity of perfluorinatedoctylic acid compounds was related to the number of C and F atoms in the molecular structure。 In conclusion, perfluorinatedoctylic acid compounds can induce apoptosis of lymphocytes in carp by the mitochondrial pathway, which is harmful to the immune system of carp。
Keyword: Perfluorinated compounds; Lymphocytes;Apoptotic signaling pathway; Toxic effects