邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸单乙基己基酯(MEHP)长期暴露对海洋青鳉(Oryzias melastigma)内分泌干扰效应的评价

为探讨邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸单乙基己基酯(MEHP)长期暴露对海水生物的内分泌干扰效应及机制,将孵化后1周的海洋青鳉(Oryzias melastigma)分别暴露于DEHP(0.1 mg·L-1和0.5 mg·L-1)和MEHP(0.1 mg·L-1和0.5 mg·L-1)6个月。结果显示:DEHP显著增加了雌性和雄性海洋青鳉的肝指数,而MEHP只在高剂量时显著增加雄性青鳉的肝指数。对于雌性青鳉,DEHP暴露后肝脏雌激素相关基因ERα、ERβ、ERγ、VTG1、VTG2、ChgH和ChgL的表达水平显著上调,而对于雄性青鳉,DEHP暴露后,只有肝脏ERβ的表达水平显著上调。相比之下,MEHP暴露对雌性和雄性青鳉肝VTG和Chg基因表达无显著影响。DEHP激活了雌性和雄性青鳉的肝过氧化物增殖激活受体PPARα和PPARγ,而MEHP只在低剂量时上调了雄性青鳉PPARγ的表达。在雌性和雄性青鳉体内,VTG和Chg的表达与ERα和ERγ的表达显著相关,并且ER与PPAR也显著相关。研究表明,DEHP长期暴露可通过激活肝性激素受体调控肝雌激素响应基因(VTG和Chg)和过氧化物增殖激活受体(PPARα和PPARγ)的表达而对海洋青鳉产生内分泌干扰效应,并且显示出性别特异性。MEHP对海洋青鳉的内分泌干扰效应弱于DEHP。     

Di (2-ethylhesyl)(DEHP)和Monoethylphthalate(MEHP)长期暴露对海洋青鳉(Oryzias melastigma)内分泌干扰效应的评价

为探讨邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸单乙基己基酯(MEHP)长期暴露对海水生物的内分泌干扰效应及机制,将孵化后1周的海洋青鳉(Oryzias melastigma)分别暴露于DEHP(0.1 mg·L^-1和0.5 mg·L^-1)和MEHP(0.1 mg·L^-1和0.5 mg·L^-1)6个月。结果显示：DEHP显著增加了雌性和雄性海洋青鳉的肝指数,而MEHP只在高剂量时显著增加雄性青鳉的肝指数。对于雌性青鳉,DEHP暴露后肝脏雌激素相关基因ERα、ERβ、ERγ、VTG1、VTG2、ChgH和ChgL的表达水平显著上调,而对于雄性青鳉,DEHP暴露后,只有肝脏ERβ的表达水平显著上调。相比之下,MEHP暴露对雌性和雄性青鳉肝VTG和Chg基因表达无显著影响。DEHP激活了雌性和雄性青鳉的肝过氧化物增殖激活受体PPARα和PPARγ,而MEHP只在低剂量时上调了雄性青鳉PPARγ的表达。在雌性和雄性青鳉体内,VTG和Chg的表达与ERα和ERγ的表达显著相关,并且ER与PPAR也显著相关。研究表明,DEHP长期暴露可通过激活肝性激素受体调控肝雌激素响应基因(VTG和Chg)和过氧化物增殖激活受体(PPARα和PPARγ)的表达而对海洋青鳉产生内分泌干扰效应,并且显示出性别特异性。MEHP对海洋青鳉的内分泌干扰效应弱于DEHP。     

S-phase,apoptosis and peroxisome proliferation in avian hepatocyte cultures following exposure to the phenoxy herbicide 2,4-D

Phenoxyherbicides induce peroxisome proliferation, as do other structurally related or unrelated chemicals which were found to be nongenotoxic carcinogens in rodents. The widespread use of 2,4-dichlorophenoxyacetic acid (2,4-D) raised concerns over the potential to produce cancer, yet results from epidemiological and experimental studies do not provide definitive evidence that 2,4-D is carcinogenic. The objective of the present study was to verify whether 2,4-D might interfere with cell growth similar to other peroxisome proliferators using cultured avian hepatocytes. Primary hepatocyte cultures from 18-day-old chick embryos were exposed to 2,4-D for up to 72 h followed by an assessment of replicative DNA synthesis and apoptosis. Further, peroxisome proliferation was evaluated. Results showed that 2,4-D stimulated DNA synthesis and suppressed spontaneous apoptosis, while the effects on peroxisome proliferation were less evident.