单 位：
中国科学院广州地球化学研究所;华南农业大学资源环境学院嘉应学院化学与环境学院华南农业大学农学院
关键词：
十溴联苯醚;秀丽隐杆线虫;繁殖;抗氧化酶;基因表达
摘 要：
十溴联苯醚(BDE-209)是一类新型持久性有机污染物,可导致神经系统和生殖发育等多种生理毒性。本文以秀丽隐杆线虫(Caenorhabditis elegans)为模式生物,通过分析十溴联苯醚(BDE-209)对其繁殖、寿命、细胞凋亡以及体内超氧化物歧化酶基因sod-3、类p-53蛋白基因cep-1、细胞色素P450基因cyp35a2以及谷胱甘肽转移酶基因gst-1的影响,来评价BDE-209的生理、细胞及分子水平毒性。试验结果表明,与空白对照相比,BDE-209低剂量(5 mg kg-1)短时间暴露,对秀丽线虫细胞凋亡及产卵影响不显著;高浓度长时间暴露(30 mg kg-1)会导致秀丽隐杆线虫产卵数目下降,寿命缩短,细胞凋亡。Real-time PCR试验表明,低剂量(5 mg kg-1)暴露使得sod-3、cep-1、cyp35a2基因表达显著增加;高剂量暴露(30 mg kg-1),虽然sod-3表达显著增加,但增加幅度低于低浓度暴露组,cep-1、cyp35a2基因表达显著受到抑制。说明长期暴露在高浓度(30 mg kg-1)十溴联苯醚环境中,会促使秀丽隐杆线虫产生氧化应激反应,秀丽隐杆线虫通过调控相关抗氧化基因的表达来修复这种损伤,而高浓度的BDE-209会造成其机体氧化损伤、细胞凋亡及产卵量下降。
译 名：
TOXICITY OF DECA-BROMINATED DIPHENYL ETHER TO CAENORHABDITIS ELEGANS
作 者：
Wang Yingli;Chen Jiansong;Yang Yuxiang;Xie Qilai;College of Natural Resources and Environment,South China Agricultural University;School of Chemistry and Environment,Jiaying University;College of Agriculture,South China Agricultural University;
关键词：
Deca-brominated diphenyl ether;;Caenorhabditis elegans;;Reproduction;;Antioxidant enzymes,Gene expression
摘 要：
Deca-brominated diphenyl ether(BDE-209)is a new kind of persistent organic pollutant,which may have multi-physiological toxic effects on the nervous system,reproduction,development,etc. of an organism. In the present study to assess toxicity of BDE-209 at the molecular,biochemical and physiological levels Caenorhabditis elegans(C. elegans)was chosen as a model organism. The physiological experiment performed in this study was to determine effects of the substance on spawning rate of parental generations and filial generations of C. elegans,and life span and cell apoptosis of the parental generations;the biochemical experiment was to monitor cell apoptosis of C. elegans with the acridine staining method;and the molecular-level experiment was to determine changes in antioxidation genes,such as superoxide dismutase-3 gene(sod-3)and quasi p53-1 protein gene(cep-1),and xenobiotic metabolism enzyme,such as cytochrome P450 35a2 gene(cyp35a2)and glutathione-s-transferase gene(gst-1)with the RealTime PCR method,so as to evaluate toxicity of BDE-209 at the physiological and molecular levels. Results show that compared with control group,exposure to a low dosage(5 mg kg-1)of BDE-209 did not have much effect on spawning rate of the parental generation,but did on that of the filial generations,particularly on that of the third filial generation,which dropped by 61.5%. Exposure to medium(20 mg kg-1)and high(30 mg kg-1)dosage of BDE-209 did inhibit their spawning rate(p<0.05)significantly,reducing that of the third filial generation by 66.7% and 89.3%,respectively. It is clearly shown that both long-time exposure to a low dosage(5 mg kg-1)and short-time exposure to a high dosage(30 mg kg-1)of BDE-209 could affect brood size of C. elegans. The experiments on life span and cell apoptosis demonstrate that exposure to a low dosage(5 mg kg-1)did not have much effect,but exposure to medium(20 mg kg-1)and high(30 mg kg-1)dosages of BDE-209 did reduce mean life span of C. elegans;and exposure to a high dosage cause apoptosis around the gential area. Real-time PCR reveals that exposure to a low dosage(5 mg kg-1)of BDE-209 significantly induced the expression of stress-related genes such as sod-3,cep-1 and xenobiotic metabolism enzyme cyp35a2 genes,but inhibited the expression of xenobiotic metabolism enzyme gst-1 genes,while exposure to a high dosage(30 mg kg-1)inhibited the expression of cep-1,cyp35a2 and gst-1,but increased the expression of sod-3 to an extent that was not so high as the former. However,it is quite obvious that the expression of gst-1 was always inhibited in either case. These findings indicate that,when exposed to a low dosage of BDE-209(5 mg kg-1)for a short time,C. elegans would react to oxidative stress,trying to repair the damage through regulating the expression of related anti-oxidation genes. In this case,C. elegans would be much affected in life span and spawning rate,however with the exposure going on,a low dosage(5 mg kg-1)of BDE-209 would significantly reduce the spawning rate of C. elegans and a high dosage of BDE-209(30 mg kg-1)would cause oxidative injury and cell apoptosis to organs of of the C. elegans,and reduce its oviposition capacity.
