INCREASED TESTICULAR CD2+ & INFERTILITY WITH VARICOCELE

睾丸 CD2 增加

• 批准号: 6743093
• 负责人: SUSAN H BENOFF
• 金额: $ 30.34万
• 依托单位: FEINSTEIN INSTITUTE FOR MEDICAL RESEARCH
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-05-01 至 2006-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6743093
• 关键词: actins; biopsy; body temperature; cadmium; clinical research; fertility; human subject; male; semen; sperm; testis disorder

DESCRIPTION: Varicocele-associated human male infertility (VAI) represents greater then 20 percent of male infertility in the US. Surgical repair of varicocele restores fertility only 1/3 of time. Identification of VAI likely to benefit from surgical correction offers health cost savings. In preliminary studies, VAI patients' seminal plasma and testes biopsies contain significantly higher cadmium (Cd2+) than other infertile males, though blood levels were indistinguishable. VAI sperm lose normal sperm surface proteins binding actin, including mannose and progesterone receptors, and normal sperm head cytoskeletal structures. In vitro incubation of fertile human sperm in Cd2+ containing media replicate VAI cytoskeletal defects. Autometallographic imaging of biopsies confirmed high Cd2+ in VAI testes. Probing serial testes sections revealed decreased actin expression with differentiation stage, and increased frequency of apoptotic nuclei in VAI tubules. Sperm voltage-dependent calcium channels (VDCC) are an apparent entry point for Cd2+ VDCC isoform expression variability correlates with mannose receptor function. VAI patient partners became pregnant within three years only if surgical correction restored normal mannose receptor function. Therefore Cd2+ may be a cofactor with heat in producing VAI. In an expanded prospective study we will determine if seminal Cd2+ correlates with testicular Cd2+, and if seminal Cd2+, testicular Cd2+ and scrotal temperature are biomarkers for VAI reversal assessed by pregnancy and birth, taking one testicular biopsy and duplicate semen samples before and 3 months after correction. Intermediate endpoints for characterizing VAI will include: seminal plasma and testicular Zn2+, testicular Cd2+ and Zn2+ distributions by autometallography, sperm response to capacitating incubation (mannose receptor assay) and to acrosome-reaction induction by polvalent mannose, assessment of actin distributions, levels of apoptosis and VDCC expression. Controls will include men from couples undergoing IVF/ICSI for non-obstructive azoospermia and males with primary VAI who refuse correction. To further characterize VAI, abnormalities in intermediate endpoints among individuals (e.g. apoptosis and actin loss) will be correlated with changes in VDCC primary structure in regions afecting metal ion sensitivity, channel gating potential and Ca2+ channel blocker binding as assesed from VDCC mRNA present in mature sperm, and with changes in a region of VDCC channel precursor sensitive to mannose-induced proteolysis, assessed by Western blot of sperm membrane proteins. Controls will include fertile donors and fertile men with varicocele.

描述：精索静脉曲张相关性男性不育(VAI)代表 在美国，超过20%的男性不育。外科修复术 精索静脉曲张只有三分之一的时间能恢复生育能力。VAI的识别可能会 手术矫正带来的好处节省了医疗成本。在预赛中 研究表明，VAI患者的精浆和睾丸活检组织中含有显著 镉(Cd~(2+))高于其他不育男性，尽管血液水平 难以辨别。VAI精子失去与肌动蛋白结合的正常精子表面蛋白， 包括甘露糖和黄体酮受体，以及正常的精子头 细胞骨架结构。可育人精子在镉离子中的体外孵育 含有可复制VAI细胞骨架缺陷的介质。自动金相术成像 的活检证实VAI睾丸中存在高CD2+。探查系列测试节 随着分化程度的升高，肌动蛋白的表达呈下降趋势 VAI肾小管上皮细胞凋亡核的频率。精子电压依赖性钙离子 通道(VDCC)是CD2+VDCC异构体表达的明显入口点 可变性与甘露糖受体功能相关。VAI患者伴侣 只有在手术矫正恢复正常的情况下，才能在三年内怀孕 甘露糖受体功能。因此，Cd~(2+)可能是一种与热有关的辅因子 生产VAI。在一项扩大的前瞻性研究中，我们将确定 CD2+与睾丸CD2+相关，如果精液中CD2+、睾丸CD2+和 阴囊温度是VAI逆转的生物标志物，通过妊娠和 出生，取一次睾丸活检并复制精液样本前和3 修正后的几个月。用于表征VAI的中间终端将 包括：精浆和睾丸锌离子，睾丸镉和锌离子 精子对获能培养反应的自显影分布 (甘露糖受体测定)和多价诱导的顶体反应 甘露糖，肌动蛋白分布、细胞凋亡水平和VDCC的评估 表情。控制措施将包括接受IVF/ICSI治疗的夫妇的男性 非梗阻性无精子症和拒绝纠正的原发VAI男性。 为了进一步表征VAI，中间终结点中的异常 个体(例如，细胞凋亡和肌动蛋白丢失)将与 影响金属离子敏感性、沟道的VDCC一次结构 VDCC mRNA检测门控电位和钙通道阻滞剂结合 存在于成熟精子中，并伴随着VDCC通道前体区域的变化 用精子蛋白印迹法评估对甘露糖诱导的蛋白降解的敏感性 膜蛋白。控制措施将包括有生育能力的捐赠者和有生育能力的男性 精索静脉曲张。