脊髓损伤后神经连接成功再生

In Breakthrough, Nerve Connections Are Regenerated After Spinal Cord Injury 突破：脊髓损伤后神经连接成功再生 译者：Docofsoul ScienceDaily (Aug. 9, 2010) — Researchers for the first time have induced robust regeneration of nerve connections that control voluntary movement after spinal cord injury, showing the potential for new therapeutic approaches to paralysis and other motor function impairments. 《每日科学》2010年8月9日报道 —— 研究者首次成功地诱导损伤后的脊髓的神经连接（控制着随意运动）再生，而且其再生势头强劲。这一研究成果显示：新的疗法在治疗瘫痪与其它运动功能障碍方面大有潜力。 New research points the way toward a potential therapy to induce regeneration of nerve connections following spinal cord injury. (Credit: iStockphoto/Feng Yu) 新的研究为发现脊髓损伤后诱导神经连接再生的富有潜力的疗法指明了道路（图片来源：iStockphoto/Feng Yu) In a study on rodents, the UC Irvine, UC San Diego and Harvard University team achieved this breakthrough by turning back the developmental clock in a molecular pathway critical for the growth of corticospinal tract nerve connections. 在一项啮齿动物的研究中，由加州大学欧文分校、加州大学圣地亚哥分校与哈佛大学的科学家组成的研究团队通过逆转对皮质脊髓束神经连接的生长至关重要的分子通道的发育时钟实现了这一医疗技术的突破。 They did this by deleting an enzyme called PTEN (a phosphatase and tensin homolog), which controls a molecular pathway called mTOR that is a key regulator of cell growth. PTEN activity is low early during development, allowing cell proliferation. PTEN then turns on when growth is completed, inhibiting mTOR and precluding any ability to regenerate. 通过删除一个名称为PTEN的酶（一种磷酸酶与张力蛋白的同族体，控制着一个称之为mTOR的分子通道，而mTOR则为细胞生长的关键调节器），该研究团队成功地完成了这一壮举。PTEN的活动度在发育的早期低，从而允许细胞的分化增殖。然后，当生长完成的时候，PTEN被打开了开关，抑制mTOR并阻止再生能力的发挥。 Trying to find a way to restore early-developmental-stage cell growth in injured tissue, Zhigang He, a senior neurology researcher at Children's Hospital Boston and Harvard Medical School, first showed in a 2008 study that blocking PTEN in mice enabled the regeneration of connections from the eye to the brain after optic nerve damage. 为了找到在损伤的组织中恢复其早期发育阶段细胞生长的方式，波士顿儿童医院与哈佛大学医学院资深神经研究者Zhigang He，在2008年的一项研究中首次显示了阻止小鼠的PTEN可使视神经损伤后重启眼脑之间的神经连接的再生过程。 He then partnered with Oswald Steward of UCI and Binhai Zheng of UCSD to see if the same approach could promote nerve regeneration in injured spinal cord sites. Results of their study appear online in Nature Neuroscience. 然后，他与加州大学欧文分校的Oswald Steward与加州大学圣地亚哥分校的Binhai Zheng合作，想搞清楚相同的方法能否促进脊髓损伤后损伤部位的神经再生。他们的研究结果出现于《Nature Neuroscience》在线版。 "Until now, such robust nerve regeneration has been impossible in the spinal cord," said Steward, anatomy & neurobiology professor and director of the Reeve-Irvine Research Center at UCI. "Paralysis and loss of function from spinal cord injury has been considered untreatable, but our discovery points the way toward a potential therapy to induce regeneration of nerve connections following spinal cord injury in people." “到目前为止，在脊髓中如此强劲的神经再生是不可能的。瘫痪与脊髓损伤后的功能丧失已被认为是不治之症，但是我们的发现指出了脊髓损伤后诱导神经连接再生的一种潜在疗法。” 解剖学与神经生物学教授、位于加州大学欧文分校内的里夫—欧文研究中心主任 Steward说。 According to Christopher & Dana Reeve Foundation data, about 2 percent of Americans have some form of paralysis resulting from spinal cord injury, which is due primarily to the interruption of connections between the brain and spinal cord. 根据克里斯托弗—戴安娜•里夫基金会的数据，大约有2%的美国人由于脊髓损伤而出现某种形式的瘫痪。这种瘫痪由大脑与脊髓的连接中断所引起。 An injury the size of a grape can lead to complete loss of function below the level of injury. For example, an injury to the neck can cause paralysis of arms and legs, loss of ability to feel below the shoulders, inability to control the bladder and bowel, loss of sexual function, and secondary health risks including susceptibility to urinary tract infections, pressure sores and blood clots due to an inability to move the legs. 一个葡萄大小的损伤可以导致损伤平面以下的功能完全丧失。比如说，颈部脊髓的损伤可以导致手臂与双腿的瘫痪、肩以下感觉的缺失、无力控制膀胱与肠的运动、性功能丧失并导致二次健康风险（包括尿道易受感染、压痛与无力移动腿部导致的血液凝块）。 "These devastating consequences occur even though the spinal cord below the level of injury is intact," Steward noted. "All these lost functions could be restored if we could find a way to regenerate the connections that were damaged." Steward解释说：“尽管损伤平面以下的脊髓完好无损，这些灾难性的结果仍然出现。如果我们能够发现让受损的神经连接再生的方式，所有这些功能的丧失都可以恢复。” He and his colleagues are now studying whether the PTEN-deletion treatment leads to actual restoration of motor function in mice with spinal cord injury. Further research will explore the optimal timeframe and drug-delivery system for the therapy. 他与其同事现在正在研究PTEN删除治疗是否确实让脊髓受损的小鼠的运动功能恢复了。进一步的研究将探索最优时间框架与这一疗法的给药系统。 Kai Liu, Yi Lu, Andrea Tedeschi, Kevin Kyungsuk Park, Duo Jin, Bin Cai, Bengang Xu and Lauren Connolly of Harvard; Jae Lee of UCSD; and Rafer Willenberg and Ilse Sears-Kraxberger of UCI also contributed to the study, which was supported by the Wings for Life Spinal Cord Research Foundation, the Craig H. Neilsen Foundation, the International Spinal Research Trust, the National Institute of Neurological Disorders & Stroke, and a private contribution to the Reeve-Irvine Research Center. 哈佛大学的Kai Liu、Yi Lu、Andrea Tedeschi、 Kevin Kyungsuk Park、Duo Jin、Bin Cai、 Bengang Xu 与 Lauren Connolly，加州大学圣地亚哥分校的Jae Lee与 加州大学欧文分校的Rafer Willenberg 与 Ilse Sears-Kraxberger也对本研究作出了贡献。本研究得到“生命之翼”脊髓研究基金会、克雷格•H•尼尔森基金会、国际脊髓研究信基金会、国立神经障碍与中风研究院的支持，一名私人通过里夫•欧文研究中心对本研究进行了捐助。