The myelin sheaths that surround all but the smallest diameter axons within the mammalian central nervous system (CNS) must maintain their structural integrity for many years. Like many tissues, however, this function is prone to the effects of ageing, and various structural anomalies become apparent in the aged CNS. Similarly, the regenerative process by which myelin sheaths, lost as a consequence of exposure to a demyelinating insult, are restored (remyelination) is also affected by age. As animals grow older, the efficiency of remyelination progressively declines. In this article, we review both phenomena and describe how both can be partially reversed by steroid hormones and their derivatives.

中文翻译：

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类固醇和与年龄相关的髓鞘逆转和髓鞘再生变化的逆转。

围绕哺乳动物中枢神经系统（CNS）内除最小直径轴突以外的所有轴突的髓鞘必须保持其结构完整性多年。但是，像许多组织一样，该功能易于老化，并且各种结构异常在老化的CNS中变得很明显。同样，由于暴露于脱髓鞘的损伤而失去的髓鞘恢复（髓鞘再生）的过程也受到年龄的影响。随着动物的长大，髓鞘再生的效率逐渐下降。在本文中，我们回顾了这两种现象，并描述了类固醇激素及其衍生物如何可以部分逆转这两种现象。