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

项目摘要/摘要 虽然激素避孕法非常有效，但对许多女性来说，它们并不是首选的方法。 国民健康统计报告表明，按需非处方药(OTC)避孕药具(即， 杀精剂和避孕套)是许多女性，特别是青少年的首选产品。不幸的是， 非处方药的失败率很高。因此，少女怀孕的比例超过70%。 美国的意外怀孕率。因此，迫切需要在以下方面进行新的和改进的- 要求为女性提供方法。在这项提案中，我们将探索一种新的女性避孕方法，该方法将针对 两个过程：1)阻断射精后精液；2)抑制女性生殖器的精子运动 一条小路。射精后，精液通过前列腺源的丝氨酸从凝胶状变为水状。 称为激肽释放酶3(KLK3)的蛋白水解酶。因此，这一应用的中心假设是药理学 阻止精液液化通过阻止精子到达精子部位而起到避孕作用 受精的问题。我们之前的工作表明，一种丝氨酸蛋白酶抑制剂有效地阻止了这两种 在雌性小鼠身上进行并防止怀孕。根据这些发现，可以假设 具有靶向活性的分子KLK3抑制剂可被开发为新型的、非激素的、完全 女性的可逆避孕药。在此应用程序中，一组调查人员将测试Small的行动 人精液中KLK3分子抑制物S与雌性恒河猴精子功能及防孕的研究 除了原型抑制剂外，还将发现KLK3的新型小分子抑制剂。这个 假说将在三个具体目标中进行检验：1)表征特定KLK3的避孕潜力 人精液中的抑制物，2)评价特异性KLK3抑制剂和“HIT”化合物(S)对人精液的细胞毒性。 人宫颈/阴道细胞和3D阴道培养，3)表征避孕效果和 雌性恒河猴体内特异性KLK3抑制剂的药效学/动力学，以及4)鉴定新药-- 比如来自DNA编码化学文库的KLK3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被开发为第一种避孕产品(即， 膜/海绵)，防止精液液化并抑制精子功能。

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.