两篇《PLos One》互撕,多生育到底加速衰老还是减缓衰老?
2016/01/25
2016年1月5日-13日,《PLos One》共刊出了两篇关于生育影响衰老速度的文章,然而这两篇文章的结论却截然相反。那么多生育到底能减缓衰老还是加速衰老?两篇文章各执一词。


2016年1月5日-13日,《PLos One》共刊出了两篇关于生育影响衰老速度的文章,然而这两篇文章的结论却截然相反。那么多生育到底能减缓衰老还是加速衰老?两篇文章各执一词。

《PLos One》1月13日:女性生育可能会加速老化

2016年1月13日,耶鲁大学研究人员在《PLos One》杂志揭示了女性生育可能会加速老化的证据,该研究由耶鲁大学与克拉科夫雅盖隆大学医学院及波兰科学院的研究人员合作完成。

研究人员检测了来自波兰南部的100名绝经后的健康女性体内与衰老相关的生物标志物,结果发现高妊娠的女性——多次怀孕、多次生育、花更多的时间进行哺乳的女性加速衰老的生物标志物水平比低妊娠的女性更高,经历过四次妊娠的孕妇体内8- OHdG(DNA氧化损伤的生物标志物)水平比普通女性高出20%,Cu-Zn SOD(铜-锌超氧化物,提供人体主要抗氧化防御的酶)含量高出60%,这意味着此类女性体内氧化应激增加,是导致衰老的重要因素。

生育与加速衰老之间的生物关系已在动物的研究中有记载,然而在人类体内从未这么明显。本文作者耶鲁大学人类学、生态学和生物进化学教授Richard Bribiescas表示,“与所有的生物一样,人类必须权衡生殖与生存资源之间的关系,特别是在农村。该研究首次提供了有利于人类做取舍的令人信服的证据。”

《PLos One》1月5日:多生育可减缓衰老

2016年1月5日,《PLos One》刊出了另外一篇关于生育与衰老进程的文章。然而,在此项研究中,Simon Fraser大学的研究人员表明高妊娠(产生较高数量的后代)的女性表现出更长的端粒,从而研究人员得出多生育可减缓衰老的结论。端粒是存在于每一条DNA链末端的保护性端点,是细胞衰老的象征。较长的端粒对于细胞复制是不可或缺的,并与寿命相关。

对于此现象,研究人员解释道,生育更多孩子的女性端粒缩短速度更慢,可能是由于雌激素的急剧增加所致,雌激素是一种有效的抗氧化剂,可保护细胞免受端粒缩短的影响,研究人员还表示受试者的生活环境也可能影响生殖力度与衰老速度之间的关系。

结语

人类对衰老的研究自古有之,科学家对衰老机制的研究囊括了基因、细胞甚至于整个生命有机体各水平,随着现代科学技术的发达,衰老的研究开始转向细胞、分子水平,并取得了许多实质性的进展。目前,关于衰老的研究机制主要有以下几个:端粒学说、长寿蛋白——GDF11 、干细胞衰老机制、生活环境、线粒体蛋白酶。然而,关于生育对衰老速度的影响,至今没有一个统一的概念。

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