Disruption of semen liquefaction using specific KLK3 inhibitors as a new contraceptive

项目概要/摘要 虽然激素避孕方法非常有效，但它们并不是许多女性的首选方法。 国家卫生统计报告表明，按需非处方（OTC）避孕药（即， 杀精剂和避孕套）是许多妇女，特别是青少年的首选产品。不幸的是， OTC方法的失败率很高。因此，青少年怀孕造成了70%以上的 美国的意外怀孕率。因此，迫切需要新的和改进的- 对妇女的需求方法。在这项建议中，我们将探索一种新的女性避孕方法， 两个过程：1）阻止射精后的精液和2）抑制女性生殖系统中的精子活力 道。射精后，通过前列腺来源的丝氨酸，精液从凝胶状变成水状 激肽释放酶3（KLK 3）。因此，本申请的中心假设是， 精液液化的阻断通过阻断精子到达该部位而提供避孕效果 受精的过程。我们以前的工作表明，丝氨酸蛋白酶抑制剂有效地阻断了这两个 并阻止雌性小鼠怀孕。根据这些发现，假设小 具有靶向活性的分子KLK 3抑制剂可被开发用作新的、非激素的、完全 女性可逆避孕药。在这个应用程序中，一个调查小组将测试小的行动， 人类精液中KLK 3分子抑制剂和精子功能，雌性恒河猴妊娠预防 猕猴，并将确定新的小分子抑制剂的KLK 3除了原型抑制剂。的 将在三个特定目的中检验假设：1）表征特定KLK 3的避孕潜力 2）为了评估特异性KLK 3抑制剂和“命中”化合物在人精液中的细胞毒性， 人宫颈/阴道细胞和3D阴道培养物，3）表征避孕功效，以及 特异性KLK 3抑制剂在雌性恒河猴中的药效学/动力学，以及4）为了鉴定新的药物- 比如从DNA编码的化学文库中提取的KLK 3特异性抑制剂。完成这项研究后，我们将能够 为了证明丝氨酸蛋白酶抑制剂是否可以作为第一种避孕产品开发（即， 膜/海绵），其防止精液液化以及抑制精子功能。

PROJECT SUMMARY/ABSTRACT While hormonal contraceptive methods are highly effective, they are not the method of choice for many women. The National Health Statistic Report indicates that on-demand over-the-counter (OTC) contraceptives (i.e., spermicides and condoms) are the products of choice for many women, especially teenagers. Unfortunately, OTC methods have high failure rates. As a result, teenage pregnancies contribute to more than 70% of unintended pregnancy rates in the United States. Therefore, there is a critical need for new and improved on- demand methods for women. In this proposal, we will explore a new female contraceptive method that will target two processes: 1) blocking post-ejaculated semen and 2) inhibiting sperm motility in the female reproductive tract. After ejaculation, semen changes from a gel-like to a watery consistency via the prostate-derived serine protease called kallikrein 3 (KLK3). Therefore, the central hypothesis for this application is that pharmacologic blockade of semen liquefaction provides a contraceptive effect by blocking sperm from reaching the site of fertilization. Our previous work showed that a serine protease inhibitor effectively blocked those two processes and prevented pregnancy in female mice. Based on these findings, it is hypothesized that small molecule KLK3 inhibitors with targeted activity can be developed for use as novel, non-hormonal, fully reversible contraceptives for women. In this application, a team of investigators will test the action of small molecule KLK3 inhibitor(s) in human semen and sperm function, pregnancy prevention in female rhesus macaques, and will identify novel small molecules inhibitors of KLK3 in addition to the prototype inhibitor. The hypothesis will be tested in three Specific Aims: 1) to characterize the contraceptive potential of specific KLK3 inhibitors in human semen, 2) To evaluate the cellular toxicity of specific KLK3 inhibitor and “hit” compound(s) in human cervical/vaginal cells and 3D vaginal cultures, 3) to characterize the contraceptive efficacy and pharmacodynamics/kinetics of specific KLK3 inhibitor in female rhesus macaques, and 4) To identify novel drug- like KLK3-specific inhibitors from DNA-encoded chemical libraries. Upon completion of this study, we will be able to demonstrate whether serine protease inhibitor can be developed as the first contraceptive product (i.e., film/sponge) that prevents semen liquefaction as well as inhibits the sperm function.