Marques Emily S, Severance Emily G, Arsenault Paige, Zahn Sarah M, Timme-Laragy Alicia R
Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA.
Antioxidants (Basel). 2024 Aug 19;13(8):1006. doi: 10.3390/antiox13081006.
Activation of Nrf2-the master regulator of antioxidative response-at different stages of embryonic development has been shown to result in changes in gene expression, but the tissue-specific and downstream effects of Nrf2 activation during development remain unclear. This work seeks to elucidate the tissue-specific Nrf2 cellular localization and the downstream changes in protein -glutathionylation during critical windows of zebrafish () development. Wild-type and mutant zebrafish embryos with a loss-of-function mutation in Nrf2a were treated with two canonical activators, sulforaphane (SFN; 40 µM) or tert-butylhydroquinone (tBHQ; 1 µM), for 6 h at either pharyngula, hatching, or the protruding-mouth stage. Nrf2a protein and -glutathionylation were visualized in situ using immunohistochemistry. At the hatching stage, Nrf2a protein levels were decreased with SFN, but not tBHQ, exposure. Exposure to both activators, however, decreased downstream -glutathionylation. Stage- and tissue-specific differences in Nrf2a protein and -glutathionylation were identified in the pancreatic islet and liver. Protein -glutathionylation in Nrf2a mutant fish was increased in the liver by both activators, but not the islets, indicating a tissue-specific and Nrf2a-dependent dysregulation. This work demonstrates that critical windows of exposure and Nrf2a activity may influence redox homeostasis and highlights the importance of considering tissue-specific outcomes and sensitivity in developmental redox biology.
已表明，在胚胎发育的不同阶段激活抗氧化反应的主要调节因子Nrf2会导致基因表达发生变化，但发育过程中Nrf2激活的组织特异性和下游效应仍不清楚。这项工作旨在阐明斑马鱼发育关键期内Nrf2的组织特异性细胞定位以及蛋白质谷胱甘肽化的下游变化。用两种典型激活剂萝卜硫素（SFN；40µM）或叔丁基对苯二酚（tBHQ；1µM）在咽期、孵化期或突嘴期对具有Nrf2a功能丧失突变的野生型和突变型斑马鱼胚胎进行6小时处理。使用免疫组织化学原位观察Nrf2a蛋白和谷胱甘肽化情况。在孵化期，暴露于SFN而非tBHQ会降低Nrf2a蛋白水平。然而，暴露于两种激活剂都会降低下游谷胱甘肽化水平。在胰岛和肝脏中发现了Nrf2a蛋白和谷胱甘肽化的阶段和组织特异性差异。两种激活剂都会使Nrf2a突变鱼肝脏中的蛋白质谷胱甘肽化增加，但胰岛中不会，这表明存在组织特异性且依赖于Nrf2a的调节异常。这项工作表明，关键暴露期和Nrf2a活性可能会影响氧化还原稳态，并突出了在发育氧化还原生物学中考虑组织特异性结果和敏感性的重要性。
