纳米金在雄性生殖毒理和雄性避孕中的功能研究

发布时间：2018-01-29 08:15

本文关键词： 纳米金血睾屏障金纳米棒光热效应雄性避孕生育力　出处：《中国科学技术大学》2014年博士论文　论文类型：学位论文

【摘要】：纳米材料中的纳米金(AuNPs)已经被应用于诊断影像学、药物载体、肿瘤的光热治疗等领域。最近,关于AuNPs作为多种药物载体进行靶向性治疗肿瘤方面的应用备受亲睐。随着AuNPs在生物医学领域中的应用增加,关于AuNPs在生物体内的命运和潜在毒性问题引起了人们的广泛关注。进年来,已有研究表明AuNPs能诱导肝脏的氧化损伤、急性炎症和细胞凋亡。相比其他器官系统来说,雄性生殖系统是一个对外界物质较为敏感、易受损的系统。然而,关于AuNPs对生殖毒性的研究,例如AuNPs在生殖器官中的分布,是否能通过生殖系统保护性屏障-血睾屏障(BTB),这些方面的问题仍然未知。我们合成了两种不同化合物修饰的纳米金,甲氧基化聚乙二醇修饰的纳米金(mPEG@AuNP)和氨基化聚乙二醇修饰的纳米金(PEG-NH2@AuNP),通过尾静脉注射成年雄性ICR小鼠。采用电感耦合等离子体质谱(ICP-MS)定量证明了纳米金能够在雄性小鼠睾丸中富集,在各检测时间点发现PEG-NH2@AuNP在小鼠睾丸中的富集量是mPEG@AuNP的两倍以上。通过暗场显微镜观察到小鼠的曲细精管的管腔中存在纳米金,说明纳米金可以通过血睾丸屏障。透射电子显微镜(TEM)证明了纳米金能通过血睾屏障并进入生精细胞。通过连续的三次重复尾静脉注射1mPEG@AuNP和PEG-NH2@AuNP到成年雄性ICR小鼠,检测小鼠的体重、激素水平、睾丸的组织形态学和精子发生过程中减数分裂同源染色体之间的联会和重组交换的研究,以及通过纳米金暴露雄性小鼠和正常雌鼠的交配的研究,证明纳米金没有明显的生殖毒性。然而,我们发现连续的三次重复尾静脉注射PEG-NH2@AuNP,能够上调小鼠的睾酮的水平,结果提示PEG-NH2@AuNP可能存在潜在毒性,提示在应用纳米金时,表面修饰是很重要的方面。研究表明纳米金没有明显的生殖毒性,我们下一步计划研究纳米金是否能在雄性生殖系统有所应用。已有研究报道表明,金纳米棒在特定波长的近红外光(NIR)的照射下能够产生局部高热。有一些研究者应用金纳米棒的光热转换效应做肿瘤的光热治疗,取得了很好的效果。同时,雄性睾丸中的精子细胞是对温度很敏感的细胞,已有报道关于热水浴杀精用于避孕方面的研究。我们结合这两方面的研究工作,旨在利用金纳米棒的光热效应解决流浪动物的避孕问题。首先,我们合成了甲氧基化聚乙二醇修饰的金纳米棒(GNR),该GNR能特异的将808纳米NIR的光能转化为热能。然后,睾丸原位注射GNR,通过控制GNR剂量和NIR的功率来实现对睾丸处的温度变化控制。最后的研究发现,在较低温度下(37℃,40℃),小鼠的睾丸部分破坏,在7天时,小鼠的生育能力下降到约10%；在60天后,小鼠的生育能力恢复到约50%。在较高温度下(45℃),小鼠的睾丸全部破坏,在7天时,小鼠的生育能力下降到约0,以后不能恢复生育力。我们提供了一个创伤小、可控的雄性避孕方法。该方法方便、有效、廉价、易操作等优点于一身,可以被选做宠物和流浪动物的节育,为下一步发展新型男性避孕技术提供了重要的依据。
[Abstract]:Gold nanoparticles in nano materials (AuNPs) have been used in diagnostic imaging, drug delivery, tumor photothermal therapy and other fields. Recently, the application of AuNPs as a drug carrier for targeted therapy of tumor has been Pro gaze. Along with the increase of AuNPs application in the biomedical field, about AuNPs in vivo fate and the potential toxicity problem has aroused extensive attention.
In recent years, studies have shown that AuNPs can induce oxidative damage in the liver, acute inflammation and apoptosis. Compared to other organ systems, the male reproductive system is one of the outside material is more sensitive, easy to damage the system. However, studies on the reproductive toxicity of AuNPs, such as AuNPs in the reproductive organs of the distribution. Whether through the barrier - protection of the reproductive system of the blood testis barrier (BTB), these problems are still unknown. We synthesized two kinds of compounds modified gold nanoparticles, gold nanoparticles methoxy polyethylene glycol (mPEG@AuNP) modified gold nanoparticles and amino modified by polyethylene glycol (PEG-NH2@AuNP), by intravenous injection of adult male ICR mice. By inductively coupled plasma mass spectrometry (ICP-MS) quantitative proof of gold nanoparticles in the testes of male mice in enrichment, found PEG-NH2@ AuNP in mouse testis at different time point detection The concentration is two times more than mPEG@AuNP. There are gold nanoparticles by dark field microscopy observed the lumen of seminiferous tube in mice, that gold nanoparticles can pass through the blood testis barrier. Transmission electron microscopy (TEM) proved that gold nanoparticles can pass through the blood testis barrier and into spermatogenic cells. Through three consecutive 1mPEG@AuNP and repeat the tail intravenous injection of PEG-NH2@AuNP to adult male ICR mice, body weight, hormone levels were detected, testicular tissue morphology and spermatogenesis in meiotic homologous chromosome synapsis and recombination between the exchange of research, and Research on exposure to mating male mice and normal female rats by gold nanoparticles, gold nanoparticles show no reproduction obvious toxicity. However, we found three repeated intravenous injection of PEG-NH2@AuNP continuous, can increase the level of testosterone in mice, the results suggest that PEG-NH2@AuNP may have potential In toxicity, it is suggested that surface modification is an important aspect in the application of nanoscale gold.
Research shows that gold nanoparticles had no obvious reproductive toxicity, whether we plan for the next step of gold nanoparticles can be used in the male reproductive system. Researchers have reported that gold nanorods in a specific wavelength of near infrared light (NIR) can produce high heat irradiation. Some researchers used photothermal therapy photothermal conversion effect of gold nanorods the tumor, and achieved good results. At the same time, male testicular sperm cells are very sensitive to the temperature of the cell, have been reported on the hot water bath for the study of spermicidal contraception. We combine these two aspects of the research work, aiming at solving the problems of stray animal use contraceptive photothermal effects of gold nanorods at first., we synthesized the methoxy polyethylene glycol modified gold nanorods (GNR), the specific GNR will convert light energy into heat. The 808 nanometer NIR and in situ testicular injection of GNR. A power control GNR dose and NIR to realize the control of temperature change on the testis. The final study found that at low temperature (37 DEG, 40 DEG C), destruction of testicle of mice, in 7 days, the fertility of mice decreased to about 10%; after 60 days, mice can birth restoring force to about 50%. at high temperature (45 DEG C), mouse testis all destroyed, in 7 days, the fertility of the mice decreased to about 0, will not restore fertility. We provide a small trauma, male contraceptive methods controlled. This method is convenient, effective, cheap, easy to operate the advantages of a, can be chosen as a pet and animal birth control, provide an important basis for the next step in the development of new male contraceptive techniques.

【学位授予单位】：中国科学技术大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TB383.1;R114

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