Selecting sperm with distinct metabolic phenotypes to increase ART efficiency

项目摘要/摘要 在美国，由于辅助生殖技术(ART)，每年有超过8万名新生儿出生。这个 ART的成功通常需要多次昂贵的周期，这些周期加起来超过了许多美国家庭每年 家庭收入。多个抗逆转录病毒治疗周期的必要性部分源于健康患者数量不足 植入前胚胎。健康的胚胎是最高质量配子的直接产物，但有限 识别最高质量精子的方法是存在的。在女性生殖道内，精子含量最高 受精能力是根据功能参数自然选择的--运动模式、趋化性、 以及顶体反应。最好的受精能力的精子也具有最低水平的氧化和 DNA损伤。不幸的是，目前选择精子进行胞浆内单精子注射的临床方法 (ICSI)请勿利用这些参数。这个应用程序的广泛目标是定义生化 精子进行运动转换和受精能力的机制和结果都将 提高基础知识水平，优化体外精子选择技术。这个 ART精子选择的优化将反过来：1)增加健康胚胎的产量；2)降低平均水平 减少昂贵周期的数量；3)减轻低收入家庭的成本负担。在目标1中，我们将利用 补充全面的生物能量表型，计算机辅助动力分析(CASA)，以及 新的脱氢酶筛选以确定可预测的代谢物的潜在机制 调节小鼠精子的基本运动模式。在目标2中，我们将测试可预测的假设 对代谢物反应的运动性变化可以用来选择最好的小鼠精子-那些正常的 形态和低水平的DNA损伤，导航到趋化信号并启动 过度活跃，并完成顶体反应。然后我们将使用体外受精(IVF)来 确定根据这些基于代谢的运动特征选择的小鼠精子是否具有增强的能力 以产生健康的胚胎。在目标3中，我们将利用我们处理小鼠精子的经验来定义 人类精子基于新陈代谢的运动反应的根本区别。这个项目是预期的 确定微环境与精子功能之间的联系机制，从而提供概念验证 为了快速开发优化临床选择具有受精能力的人类精子的方法 艺术。

PROJECT SUMMARY/ABSTRACT More than 80,000 births in the US occur annually as a result of assisted reproductive technology (ART). The success of ART typically requires multiple expensive cycles that together exceed many US families’ yearly household incomes. The necessity of multiple ART cycles stems in part from an insufficient number of healthy preimplantation embryos. Healthy embryos are a direct product of the highest-quality gametes, yet limited methods exist to identify the highest-quality sperm. Within the female reproductive tract, sperm with the highest fertilization competence are naturally selected based on functional parameters – motility patterns, chemotaxis, and the acrosome reaction. The best fertilization-competent sperm also have the lowest levels of oxidative and DNA damage. Unfortunately, current clinical methods for selecting sperm for intracytoplasmic sperm injection (ICSI) do not leverage these parameters. The broad objective of this application is to define the biochemical mechanisms by which sperm undergo motility switching and fertilization competence, and results will both advance the state of basic knowledge and enable optimization of in vitro sperm selection techniques. The optimization of sperm selection for ART will in turn: 1) increase production of healthy embryos; 2) reduce average numbers of costly cycles; and thus 3) lessen the cost burden on lower-income families. In Aim 1, we will utilize complementary comprehensive bioenergetic phenotyping, computer assisted motility analysis (CASA), and a novel dehydrogenase screen to define the underlying mechanisms through which metabolites predictably modulate the essential motility patterns of mouse sperm. In Aim 2, we will test the hypothesis that predictable motility changes in response to metabolites can be used to select the best mouse sperm – those with normal morphology and low levels of DNA damage, the ability to navigate towards a chemotactic signal and initiate hyperactive motility, and complete the acrosome reaction. We will then employ in vitro fertilization (IVF) to determine whether mouse sperm selected based on these metabolism-based motility traits have enhanced ability to generate healthy embryos. In Aim 3, we will exploit our experience working with mouse sperm to define the fundamental differences in the metabolism-based motility responses of human sperm. This project is expected to identify the mechanisms connecting microenvironment to sperm function and thereby provide proof-of-concept for the rapid development of methods to optimize clinical selection of fertilization-competent human sperm for ART.