내분비계 장애물질이 어류의 HPG, HPT, HPA 축에 미치는 연계영향

Abstract

*Department of Environmental Health, Graduate School of Yongin University**Department of Occupational and Environmental Health, College of Environmental Sciences, Yongin UniversityABSTRACTObjectives: The objective of this review was to summarize the primary role of three representative endocrineaxes in aquatic vertebrates and discuss the effects on endocrine systems and their interactions in teleost fish afterexposure to environmental contaminants.Methods: We summarized individual traits and mechanisms for hormonal and transcriptional interactionsbetween the hypothalamic-pituitary-gonad (HPG), hypothalamic-pituitary-thyroid (HPT), and hypothalamic-pituitary-adrenal (HPA) axes in fish. We also provided a brief discussion on the effects of nonylphenol-inducedtoxicity on endocrine systems and their interactions in fish as a demonstration of holistic explanation.Results: Currently-available data showed that thyroid dysfunction is associated with reproductive toxicity dueto changes in steroidogenic gene expressions and sex hormone levels as well as gonad glands in fish. As anexample, we demonstrated that exposure to nonylphenol could induce estrogenicity in male fish by decreasingthyroid hormones, which contributes to increased aromatase expression. Although the mechanisms arecomplicated and involved in multiple ways, a number of studies have shown that sex steroids influence the HPTaxis or the HPA axis in fish, indicating bi-directional crosstalk. Critically missing is information on the primarytarget or toxicity mechanisms of environmental contaminants among the three endocrine axes, so further studiesare needed to explore those possibilities.Conclusions: This review highlights the interactions between the HPG, HPT, and HPA axes in fish in order tobetter understand how these endocrine systems could interact with each other in situations of exposure toendocrine disrupting chemicals.Key words: Interaction, endocrine disruption, HPG axis, HPT axis, HPA axis