Department of AnatomyUniversity of Otago, Dunedin, New Zealand
Department of AnatomyUniversity of Otago, Dunedin, New Zealand.
Reproduction. 2017 Dec;154(6):R149-R160. doi: 10.1530/REP-17-0408. Epub 2017 Sep 10.
Cortisol is the main glucocorticoid (GC) in fish and the hormone most directly associated with stress. Recent research suggests that this hormone may act as a key factor linking social environmental stimuli and the onset of sex change by initiating a shift in steroidogenesis from estrogens to androgens. For many teleost fish, sex change occurs as a usual part of the life cycle. Changing sex is known to enhance the lifetime reproductive success of these fish and the modifications involved (behavioral, gonadal and morphological) are well studied. However, the exact mechanism behind the transduction of the environmental signals into the molecular cascade that underlies this singular process remains largely unknown. We here synthesize current knowledge regarding the role of cortisol in teleost sex change with a focus on two well-described transformations: temperature-induced masculinization and socially regulated sex change. Three non-mutually exclusive pathways are considered when describing the potential role of cortisol in mediating teleost sex change: cross-talk between GC and androgen pathways, inhibition of aromatase expression and upregulation of (the gene encoding anti-Müllerian hormone). We anticipate that understanding the role of cortisol in the initial stages of sex change will further improve our understanding of sex determination and differentiation across vertebrates, and may lead to new tools to control fish sex ratios in aquaculture.
皮质醇是鱼类中的主要糖皮质激素 (GC)，也是与应激最直接相关的激素。最近的研究表明，这种激素可能通过启动从雌激素到雄激素的类固醇生成的转变，作为将社会环境刺激与性别转变联系起来的关键因素。对于许多硬骨鱼来说，性别转变是生命周期的正常部分。众所周知，性别转变可以提高这些鱼类的终生繁殖成功率，并且涉及的变化（行为、性腺和形态）已经得到了很好的研究。然而，将环境信号转导为分子级联的具体机制，从而引发这种独特的过程，在很大程度上仍然未知。在这里，我们综合了目前关于皮质醇在硬骨鱼性别转变中的作用的知识，重点介绍了两种描述良好的转变：温度诱导的雄性化和社会调节的性别转变。在描述皮质醇在介导硬骨鱼性别转变中的潜在作用时，考虑了三种非相互排斥的途径：GC 和雄激素途径之间的串扰、芳香酶表达的抑制和（编码抗缪勒管激素的基因）的上调。我们预计，了解皮质醇在性别转变初始阶段的作用将进一步提高我们对脊椎动物性别决定和分化的理解，并可能导致新的工具来控制水产养殖中的鱼类性别比例。
