Multifactorial regulation of reproduction and gonadal function in fish

NSERC的发现基金是我整个研究计划的基石，其长期目标是研究鱼类生殖和生长的激素控制。促性腺激素和促生长激素过程高度整合，涉及脑垂体外周轴的激素。在从生殖阶段到生长阶段的过渡期间和之后，代谢的变化是必不可少的，特别是在卵生物种，如在配子发生期间需要高能量的鱼类。我们的研究结果表明，甲状腺激素，下丘脑促性腺激素抑制激素（GnIH）和促性腺激素释放激素（GnRH），在控制垂体促性腺激素（LH和FSH）和生长激素（GH）的生产在金鱼的关键球员。同样的肽（GnRH和GnRH），在卵巢和睾丸中产生，也参与鱼类配子发生的旁分泌控制。一般假设：甲状腺激素（TH）与垂体促性腺激素（LH和FSH）、生长激素（GH）和性腺激素（类固醇和肽）一起调节鱼类的生殖、代谢和配子发生。 为了验证这一假设，我们将调查在促生长和促性腺激素阶段的垂体激素生产的控制和研究代谢途径的变化，需要维持生殖和生长旺盛。此外，我们将建立在我们过去的工作，调查甲状腺激素作为一个复杂的多因子系统，通过与性腺激素的相互作用，调节睾丸发育和配子发生的一个组成部分的作用。我建议的研究将集中在两个直接相关的主要研究领域，并同时进行调查：A）TH在鱼类生殖和生长阶段垂体激素产生的季节性相关多因素调节中的作用&相关的代谢能量分配B）甲状腺激素与大脑、垂体、以及调节睾丸功能和精子发生的性腺激素。拟议的研究将被用作比较内分泌学广泛领域的HQP培训工具，并将涉及研究生和本科生以及访问科学家。我致力于在培训环境中推广EDI，并将尽一切努力提供一个没有骚扰、欺凌和歧视的安全工作环境。这些发现将增强我们对生殖和生长的综合控制以及鱼类代谢的相关变化的理解，并提供与其他脊椎动物物种相关的鱼类睾丸发育和配子发生综合调控的关键信息。拟议的研究将通过提高我们评估环境污染物在水生生态系统中具有类似生物活性的不利影响的能力，在环境毒理学方面具有转化潜力。

The NSERC discovery grant has been the cornerstone of my entire research program, with a long-term objective to investigate the hormonal control of reproduction and growth in fish. Gonadotropic and somatotropic processes are highly integrated and involve the hormones of the brain-pituitary-peripheral axis. Changes in metabolism are essential during and after the transition from reproductive to growth phase, especially in oviparous species like fish with high energy demands during gametogenesis. Our findings indicate that thyroid hormones, the hypothalamic gonadotropin inhibiting hormone (GnIH), and gonadotropin-releasing hormone (GnRH), are critical players in the control of pituitary gonadotropin (LH &FSH) and growth hormone (GH) production in goldfish. The same peptides (GnIH and GnRH), produced in the ovary and testis, are also involved in the paracrine control of gametogenesis in fish. General hypothesis: thyroid hormones (THs) work in concert with the pituitary gonadotropins (LH and FSH), growth hormone (GH), and gonadal hormones (steroids & peptides) to regulate reproduction, metabolism, and gametogenesis in fish. To test this hypothesis, we will investigate the control of pituitary hormone production during somatotropic and gonadotropic phases and study changes in metabolic pathways required to sustain reproduction and growth energetically. Furthermore, we will build on our past work to investigate the role of thyroid hormones as a component of a complex multifactorial system that regulates testicular development and gametogenesis through interaction with gonadal hormones. My proposed research will focus on two primary research areas which are directly related and conducted simultaneously to investigate: A)The role of THs in the seasonally related multifactorial regulation of pituitary hormone production & related metabolic energy allocation during reproductive and growth phases in fish B)The role of thyroid hormones working in concert with the brain, pituitary, and gonadal hormones to regulate testicular function and spermatogenesis. The proposed research will be used as a vehicle for HQP training in the broad areas of comparative endocrinology and will involve graduate and undergraduate students and visiting scientists. I am committed to promoting EDI in the training environment and will make every effort to provide a safe working environment free from harassment, bullying, and discrimination. The findings will enhance our understanding of the integrated control of reproduction and growth and associated changes in fish metabolism and provide crucial information on the integrated regulation of testicular development and gametogenesis in fish with relevance to other vertebrate species. The proposed studies will have translational potential in environmental toxicology by improving our ability to assess adverse impacts of environmental contaminants with hormone-like activities in the aquatic ecosystem.