Abstract:
The dinitrophenol herbicide dinoseb is an uncoupler of mitochondrial oxidative phosphorylation (OXPHOS). Studies in fish demonstrate impaired OXPHOS is associated with altered immune system responses and locomotor activity in fish. The objective of this study was to determine the effect of dinoseb on zebrafish (Danio rerio) during early stages of development. We measured oxygen consumption rates of embryos, transcripts related to OXPHOS, growth, and the immune system (cytokines and immune-signaling transcripts), and locomotor activity. We hypothesized that OXPHOS of fish would be impaired in vivo, leading to altered basal immune system expression and locomotor activity. Oxidative respiration assessments in embryos revealed that dinoseb decreased both mean basal respiration and oligomycin-induced ATP-linked respiration. Expression levels of cytochrome c oxidase complex IV, 3-hydroxyacyl-COA dehydrogenase and superoxide dismutase 1 were decreased in larvae following exposure to dinoseb while succinate dehydrogenase complex flavoprotein subunit A, insulin growth factor 1 (igf1) and igf2a mRNA were increased in abundance. Immune-related transcripts chemokine (C-X-C motif) ligand 1 and matrix metallopeptidase 9 (MMP-9) were decreased in expression levels while toll-like receptor 5a and 5b were increased in expression. In addition, a visual motor response test was conducted on both 6 and 7 dpf larvae to determine if dinoseb impaired locomotor activity. Dinoseb decreased locomotor activity in 7 dpf larvae but not 6 dpf. This study improves knowledge of toxicity mechanisms for dinoseb in early stages of fish development and demonstrates that mitochondrial toxicants may disrupt immune signaling in zebrafish.
摘要:
二硝基苯酚除草剂dinoseb是线粒体氧化磷酸化(OXPHOS)的解偶联剂。鱼类研究表明,OXPHOS受损与鱼类免疫系统反应和运动活动的改变有关。这项研究的目的是确定dinoseb在发育早期对斑马鱼(Daniorerio)的影响。我们测量了胚胎的耗氧率,与OXPHOS相关的转录本,增长,和免疫系统(细胞因子和免疫信号转录本),和运动活动。我们假设鱼的OXPHOS会在体内受损,导致基础免疫系统表达和运动活动改变。胚胎中的氧化呼吸评估显示,dinoseb降低了平均基础呼吸和寡霉素诱导的ATP相关呼吸。细胞色素C氧化酶复合物Ⅳ的表达水平,暴露于dinoseb后,幼虫中的3-羟基酰基-COA脱氢酶和超氧化物歧化酶1降低,而琥珀酸脱氢酶复合黄素蛋白亚基A,胰岛素生长因子1(igf1)和igf2amRNA丰度增加。免疫相关转录本趋化因子(C-X-C基序)配体1和基质金属肽酶9(MMP-9)的表达水平降低,而toll样受体5a和5b的表达增加。此外,对6和7dpf幼虫进行视觉运动反应测试,以确定dinoseb是否损害了运动活动。Dinoseb降低了7dpf幼虫的运动活性,但没有降低6dpf。这项研究提高了对鱼类发育早期dinoseb毒性机制的认识,并证明了线粒体毒物可能会破坏斑马鱼的免疫信号。