Targeting Na,K-ATPase alpha4 for male contraception

靶向 Na,K-ATPase α4 的男性避孕

• 批准号: 10239052
• 负责人: V GUSTAVO BLANCO
• 金额: $ 49.76万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-15 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10239052
• 关键词: ATPase inhibitory protein; Affect; Affinity; Animals; Antihistamines; Appearance; Area; Binding; Binding Proteins; Biochemical; Biological; Biological Availability; Biological Markers; Cell membrane; Cells; Characteristics; Chemicals; Clinical; Clinical Research; Contraceptive Agents; Contraceptive methods; Data; Drug Kinetics; Drug Targeting; Effectiveness; Epididymis; Ethers; Female; Female genitalia; Fertility; Fertilization in Vitro; Future; Gland; Goals; Human; Hyperactivity; In Vitro; Infertility; Investigational Drugs; Ions; Knockout Mice; Lead; Male Contraceptive Agents; Male Infertility; Maximum Tolerated Dose; Meiosis; Membrane Potentials; Metabolic; Metabolism; Mus; Mutation; Na(+)-K(+)-Exchanging ATPase; Oral; Oral Contraceptives; Ouabain; Partner in relationship; Permeability; Ph+ ALL; Pharmaceutical Chemistry; Pharmacology; Pilot Projects; Plasma; Population; Property; Protein Isoforms; Proteins; Public Health; Research; Safety; Series; Site; Solubility; Source; Specificity; Sperm Capacitation; Sperm Motility; Sperm Tail; Spermatocytes; Spermatogenesis; Sterility; Surface; System; Testing; Testis; Toxic effect; Validation; Woman; absorption; analog; base; birth control; cell motility; druggable target; efficacy study; experimental study; extracellular; improved; in silico; in vivo; inhibitor/antagonist; male; male fertility; men; molecular size; monolayer; novel; pre-clinical; preclinical study; progenitor; programs; reproductive tract; reversible contraceptive; scaffold; scale up; side effect; small molecule; sperm cell; sperm function; unintended pregnancy; virtual screening

PROJECT SUMMARY / ABSTRACT The rapidly growing world population and the high rate of unintended pregnancies make contraception a need and a priority for any public health program. While several contraceptive methods, with varying efficacy are currently available for women, a more comprehensive approach to birth control requires extending contraception to males. However, a safe, effective and reversible contraceptive for men is still unavailable. An attractive approach to develop male contraceptives consists in targeting proteins that are specifically expressed in sperm and are required for sperm fertility. We have shown that Na,K-ATPase α4 (NKAα4), a plasma membrane ion transporter which exchanges cytoplasmic Na+ for extracellular K+, is a validated target for male contraception. NKAα4 is uniquely expressed in testis male germ cells after meiosis, is particularly abundant in the sperm flagellum, and is critical for sperm function. Deletion of NAKα4 in mice results in complete sterility of only the male but not the female animals. NKAα4 is essential for sperm motility and sperm capacitation. Its activity maintains sperm intracellular Na+ levels ([Na+]i) and several vital sperm parameters, including membrane potential (Vm), intracellular Ca+2 ([Ca2+]i) and pH. From a biochemical standpoint, NKAα4 has a particularly high affinity for ouabain, the specific inhibitor of Na,K-ATPase. We took advantage of this property to specifically target NKAα4 and block its function to achieve male infertility. We synthesized a series of small molecule compounds, which can selectively bind to the high ouabain affinity site of NKAα4. Some of these compounds inhibit NKAα4 and affect sperm motility both in vitro and after administration to mice. This provides strong evidence for the suitability of NKAα4 as a pharmacological target and our compounds as agents that can be used for the control of male fertility. However, before NKAα4 inhibitors can be moved forward into their application as male contraceptives, it is necessary that their efficacy, drug-target interaction, biomarkers for their in vitro and vivo specificity, side effects, mechanisms of action and pharmacokinetic parameters are identified and optimized for future clinical use. We will test this in two aims. In specific aim 1, we will develop compounds with the capacity to selectively inhibit NKAα4 and block sperm function, which will be ready for testing in mice. Then, during specific aim 2, we will perform studies to obtain preclinical validation to advance the NKAα4 inhibitors as male contraceptives. A series of rigorous approaches from the medicinal chemistry and biological areas will be used to identify the compounds which will have the characteristics that will be necessary for male contraception. This research will be essential to fulfill the highly desired unmet goal of obtaining a non-hormonal pharmacological agent that could be used as an oral, reversible agent for the control of male fertility.

项目摘要 /摘要 迅速增长的世界人口和意外怀孕的高率使违约 任何公共卫生计划的需求和优先事项。而几种避孕方法，效率不同 目前可用于女性，一种更全面的节育方法需要扩展 男性避孕。但是，对于男性来说，一种安全，有效和可逆的避孕药仍然不可用。一个 有吸引力的开发男性避孕药的方法包括靶向特定的蛋白质 用精子表达，是精子生育所必需的。我们已经表明Na，K-ATPaseα4（NKAα4），a 质膜离子转运蛋白将细胞质Na+交换为细胞外K+是一个经过验证的靶标 用于男性避孕。 NKAα4在减数分裂后在睾丸雄性细胞中唯一表达，尤其是 富含精子鞭毛，对于精子功能至关重要。小鼠Nakα4的删除导致 完全不育，而不是雄性动物的无菌性。 NKAα4对于精子运动和精子至关重要 电容。它的活性维持精子内Na+水平（[Na+] I）和几个重要的精子参数， 包括膜电位（VM），细胞内Ca+2（[Ca2+] I）和pH。从生化的角度来看，NKAα4 对Na，K-ATPase的特异性抑制剂Ouabain具有特别高的亲和力。我们利用了这个 特定靶向NKAα4并阻止其功能以实现男性不育症的财产。我们合成了一个系列 小分子化合物的含量，可以选择性地与NKAα4的高乌巴因亲和位点结合。其中一些 这些化合物抑制NKAα4，并在体外和给药后影响精子运动。这 提供了有力的证据证明NKAα4作为药物目标的适用性，我们的化合物作为 可用于控制男性生育能力的药物。但是，在移动NKAα4抑制剂之前 将其作为男性避孕药的应用，有必要使他们的效率，药物目标相互作用， 其体外和体内特异性，副作用，作用机制和药代动力学机制的生物标志物 识别并优化了参数，以供将来的临床使用。我们将以两个目标进行测试。在特定的目标1中， 我们将开发具有选择性抑制NKAα4和阻断精子功能的能力的化合物，这将 准备在小鼠中进行测试。然后，在特定目标2期间，我们将进行研究以获得临床前验证 将NKAα4抑制剂作为雄性避孕药。医学上的一系列严格方法 化学和生物区域将用于识别具有具有特征的化合物 男性违规是必要的。这项研究对于实现高度期望的未满足目标至关重要 获得的非荷尔蒙药理剂，该药理可以用作口服的，可逆的药物 控制男性生育能力。