Xenoestrogen regulation of Leydig cells

异雌激素对间质细胞的调节

• 批准号: 8072901
• 负责人: Benson Tokunbo Akingbemi
• 金额: $ 1.55万
• 依托单位: AUBURN UNIVERSITY AT AUBURN
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8072901
• 关键词: 1-Phosphatidylinositol 3-Kinase; Address; Adult; Affect; Age; Air; Amniotic Fluid; Androgen Receptor; Androgens; Animal Feed; Aromatase; Biology; Biomedical Research; Busulfan; Canis familiaris; Cell Communication; Cell Count; Cell Differentiation process; Cell Proliferation; Cell Survival; Cell physiology; Cells; Cereals; Chemicals; Child; Clinical; Conditioned Culture Media; Data; Development; Diabetes Mellitus; Diet; Endocrine; Environment; Epidermal Growth Factor Receptor; Estradiol; Estrogen Receptors; Estrogens; Exposure to; Family suidae; Fetus; Figs - dietary; Food; Food Supply; Fostering; Future; Gene Expression; Gene Silencing; Genes; Genistein; Goals; Gonadal Steroid Hormones; Growth Factor; Growth Factor Receptors; Hormonal; Human; Human Development; In Vitro; Incidence; Infant; Infant formula; Institutes; Insulin; Insulin Receptor; Investigation; Isoflavones; Link; Literature; Long-Evans Rats; Luteinizing Hormone; Mediating; Mediation; Mesenchymal; Mission; Mitogen-Activated Protein Kinases; Mitosis; Modeling; Molecular; Mothers; Mutation; National Institute of Environmental Health Sciences; Neonatal; Nuclear; Obesity; Pathway interactions; Patients; Perinatal; Phytoestrogens; Pituitary Gland; Population; Pregnancy; Procedures; Property; Proteins; Proto-Oncogene Proteins c-akt; Public Health; Pulmonary Heart Disease; Rattus; Regulation; Reporting; Reproduction; Reproductive Health; Reproductive Periods; Research; Research Training; Rodent; Role; Route; Seminal fluid; Serum; Signal Pathway; Signal Transduction; Signaling Molecule; Somatic Cell; Source; Soybeans; Students; Techniques; Terrorism; Testis; Testosterone; Time; Tissues; Toxic effect; United States; Veterinarians; Water; Work; base; cell growth; daidzein; design; early life exposure; feeding; graduate student; in vivo; in vivo Model; leydig interstitial cell; male; meetings; neonatal exposure; neonate; nonhuman primate; offspring; paracrine; postnatal; pregnant; prenatal; prepuberty; progenitor; public health relevance; receptor; reproductive; research study; sertoli cell; soy; soy protein isolate; spermatogenic epithelium structure; transcription factor; xenoestrogen

DESCRIPTION (provided by applicant): Soy isoflavones possess estrogenic properties, and reproductive tract tissues (including Leydig cells) express estrogen receptors (ER1 and ER2). Leydig cells are the predominant source of the male sex steroid hormone testosterone. Approximately 15% of infants fed soy-based formulas in the United States each year are exposed to the phytoestrogens genistein and daidzen, which are the predominant isoflavones in soybeans. Several reports in the literature have shown that exposure of rodents and non human primates to soy isoflavones affect testicular androgen secretion. However, the mechanisms by which soy isoflavones act in Leydig cells have not been investigated. The P.I. hypothesizes that disparities in serum androgen levels and Leydig cell steroidogenic capacity are linked to differences in the numbers of Leydig cells. Consistent with this hypothesis are recent observations indicating that genistein regulates Leydig cell mitosis. Also, soy isoflavones are known to regulate development of somatic cells in the testis, e.g. Sertoli cells. Therefore, cell-cell interactions, e.g., between Sertoli cells and Leydig cells, are subject to regulation by soy isoflavones. To address these issues, experiments will be performed to achieve the following aims: I. Soy isoflavone regulation of mesenchymal Leydig cell precursors; II. Mechanisms of genistein action in Leydig cells; and, III. Sertoli cell-mediated regulation of Leydig cells. The proposed study is relevant to public health and will be the first to define the mechanisms and molecular pathways of estrogen action in Leydig cells. Also, results will promote informed use of soy isoflavones in the diet, especially in neonates, in which the developing reproductive tract is sensitive to changes in the hormonal milieu. Furthermore, the present application will provide research training to undergraduate, professional and graduate students. The growing public concern for agri-terrorism puts veterinarians in the fore-front of research to aid defense of food supplies just as biomedical research is increasingly benefiting from investigation conducted in food animal species, e.g., use of pigs to study obesity and diabetes and dogs for cardiopulmonary diseases. Therefore, research training afforded by the present application will contribute to efforts geared to preparing future veterinarians to meet these challenges. PUBLIC HEALTH RELEVANCE: Soy isoflavones possess estrogenic properties, and reproductive tract tissues (including Leydig cells) express ER1 and ER2. Because proliferative activity in Leydig cells, which determines the final number of Leydig cells, is restricted to the prepubertal period, modulation of Leydig cell mitosis in the prepubertal period has consequences for Leydig cell numbers in the adult testis. The present application is designed to identify the mechanisms by which soy isoflavones cause long-lasting effects on testicular androgen secretion using the rat model. Experiments will be performed to address three Specific Aims: Soy isoflavones affect mesenchymal Leydig cell precursors in the prenatal and/or neonatal period, which alters Leydig cell proliferation and population (Aim I); Estrogen regulation of Leydig cell mitosis is mediated by interaction of signaling pathways, which involves the cell survival factor protein Akt (protein kinase B) acting in concert with estrogen receptor ER1, epidermal growth factor receptors (EGFR), insulin growth factor-1 receptors (IGF-1R) and mitogen activated protein kinases (MAPK) (Aim II); and, Action of soy isoflavones in Sertoli cells affects Leydig cells (Aim III). Timed pregnant dams will be fed diets containing low and high isoflavone levels (5, 1000 ppm) in the perinatal period. Male offspring will be analyzed for Leydig cell proliferation in prepubertal and pubertal rats. In addition, the number of Leydig cells will be enumerated by stereology in the adult testis at 90 days of age. Analysis of genistein action regulating Leydig cell mitosis will involve use of pharmacological inhibition and gene silencing techniques to investigate the role of Akt, ER1, EGFR and IGF1-R. The possibility that soy isoflavones act directly in the seminiferous epithelium will be investigated by analysis of Sertoli cell differentiation and maturation. In addition, Sertoli cell-Leydig cell interactions will be evaluated by culture of Leydig cells in Sertoli cell-conditioned media. The proposed experiments will be the first to investigate the mechanisms of soy isoflavone action in Leydig cells. In particular, the EDS- and busulfan-treated rat models provide opportunities to study cell proliferation and cell-cell interactions in vivo. These models have contributed immensely to our understanding of testicular biology but have not been used in toxicological studies. Also, the hypothesis that estrogenic compounds, and perhaps other endocrine-active agents, may exert indirect effects in Leydig cells by action exerted in Sertoli cells has not been explored. Together, these approaches will yield information not previously described for phytoestrogen action in testicular cells. The information will contribute to ongoing about potential reproductive toxicity of soy-based diets especially in neonates. The growing public concern for agri-terrorism represents a challenge to veterinarians who have responsibilities for defense of food supplies. Also, biomedical research is increasingly benefiting from investigation conducted in food animal species, e.g., use of pigs to study obesity and diabetes and dogs for cardiopulmonary diseases. Research training to be afforded by the present application to professional veterinary students will contribute to efforts geared to preparing future veterinarians to meet these challenges.

描述（申请人提供）：大豆异黄酮具有雌激素特性，生殖道组织（包括间质细胞）表达雌激素受体（ER1和ER2）。间质细胞是男性性类固醇激素睾酮的主要来源。在美国，每年大约 15% 的食用大豆配方奶粉的婴儿接触到植物雌激素金雀异黄酮和大豆异黄酮，它们是大豆中的主要异黄酮。文献中的一些报告表明，啮齿动物和非人类灵长类动物接触大豆异黄酮会影响睾丸雄激素的分泌。然而，大豆异黄酮在间质细胞中的作用机制尚未得到研究。 P.I.假设血清雄激素水平和间质细胞类固醇生成能力的差异与间质细胞数量的差异有关。最近的观察表明金雀异黄素调节间质细胞有丝分裂，与这一假设相一致。此外，已知大豆异黄酮可以调节睾丸中体细胞的发育，例如睾丸细胞。支持细胞。因此，细胞与细胞的相互作用，例如支持细胞和间质细胞之间的相互作用，受到大豆异黄酮的调节。为了解决这些问题，将进行实验以实现以下目标： I. 大豆异黄酮对间充质 Leydig 细胞前体的调节；二.金雀异黄素在 Leydig 细胞中的作用机制；以及，三。支持细胞介导的间质细胞调节。拟议的研究与公共卫生相关，将是第一个定义雌激素在间质细胞中作用的机制和分子途径的研究。此外，研究结果将促进在饮食中合理使用大豆异黄酮，尤其是新生儿，因为新生儿的生殖道发育对激素环境的变化很敏感。此外，本应用程序将为本科生、专业学生和研究生提供研究培训。公众对农业恐怖主义的日益关注使兽医走在研究的前沿，以帮助保卫粮食供应，正如生物医学研究越来越受益于对食用动物物种进行的调查，例如使用猪来研究肥胖和糖尿病以及狗用于心肺疾病。因此，本申请提供的研究培训将有助于帮助未来的兽医应对这些挑战。公共健康相关性：大豆异黄酮具有雌激素特性，生殖道组织（包括间质细胞）表达 ER1 和 ER2。由于决定睾丸间质细胞最终数量的睾丸间质细胞增殖活性仅限于青春期前，因此青春期前睾丸间质细胞有丝分裂的调节会对成年睾丸中睾丸间质细胞的数量产生影响。本申请旨在利用大鼠模型鉴定大豆异黄酮对睾丸雄激素分泌产生长期影响的机制。将进行实验以实现三个具体目标： 大豆异黄酮影响产前和/或新生儿期的间充质间质细胞前体，从而改变间质细胞增殖和数量（目标 I）；雌激素对 Leydig 细胞有丝分裂的调节是通过信号通路的相互作用介导的，其中涉及细胞生存因子蛋白 Akt（蛋白激酶 B）与雌激素受体 ER1、表皮生长因子受体 (EGFR)、胰岛素生长因子 1 受体协同作用。 IGF-1R) 和丝裂原激活蛋白激酶 (MAPK) (Aim II)；并且，大豆异黄酮在支持细胞中的作用会影响间质细胞（目标 III）。定时怀孕的母鼠将在围产期饲喂含有低异黄酮水平和高异黄酮水平（5、1000 ppm）的饮食。将分析雄性后代青春期前和青春期大鼠的间质细胞增殖情况。此外，将在 90 日龄时通过体视学计数成年睾丸中 Leydig 细胞的数量。对金雀异黄素调节 Leydig 细胞有丝分裂的作用的分析将涉及使用药理学抑制和基因沉默技术来研究 Akt、ER1、EGFR 和 IGF1-R 的作用。将通过分析支持细胞的分化和成熟来研究大豆异黄酮直接作用于生精上皮的可能性。此外，支持细胞-间质细胞相互作用将通过在支持细胞条件培养基中培养间质细胞来评估。拟议的实验将是第一个研究大豆异黄酮在 Leydig 细胞中作用机制的实验。特别是，EDS 和白消安处理的大鼠模型为研究体内细胞增殖和细胞间相互作用提供了机会。这些模型极大地促进了我们对睾丸生物学的理解，但尚未用于毒理学研究。此外，雌激素化合物以及其他内分泌活性剂可能通过在支持细胞中发挥作用而对间质细胞产生间接影响的假设尚未得到探索。总之，这些方法将产生以前未描述的睾丸细胞中植物雌激素作用的信息。这些信息将有助于持续了解以大豆为基础的饮食的潜在生殖毒性，尤其是对新生儿的潜在生殖毒性。公众对农业恐怖主义日益增长的关注对负责保卫粮食供应的兽医构成了挑战。此外，生物医学研究越来越受益于对食用动物物种的研究，例如使用猪来研究肥胖和糖尿病，使用狗来研究心肺疾病。本应用程序为专业兽医学生提供的研究培训将有助于为未来的兽医做好准备以应对这些挑战。