Kohama Steven G, Rosene Douglas L, Sherman Larry S
Oregon National Primate Research Center, Oregon Health and Science University, Portland, OR, USA.
Age (Dordr). 2012 Oct;34(5):1093-110. doi: 10.1007/s11357-011-9357-7. Epub 2011 Dec 28.
The cognitive decline associated with normal aging was long believed to be due primarily to decreased synaptic density and neuron loss. Recent studies in both humans and non-human primates have challenged this idea, pointing instead to disturbances in white matter (WM) including myelin damage. Here, we review both cross-sectional and longitudinal studies in humans and non-human primates that collectively support the hypothesis that WM disturbances increase with age starting at middle age in humans, that these disturbances contribute to age-related cognitive decline, and that age-related WM changes may occur as a result of free radical damage, degenerative changes in cells in the oligodendrocyte lineage, and changes in microenvironments within WM.
长期以来，人们一直认为与正常衰老相关的认知衰退主要是由于突触密度降低和神经元丧失。最近在人类和非人类灵长类动物身上的研究对这一观点提出了挑战，转而指出白质（WM）的紊乱，包括髓鞘损伤。在这里，我们回顾了人类和非人类灵长类动物的横断面和纵向研究，这些研究共同支持了以下假设：WM紊乱从人类中年开始随年龄增长而增加，这些紊乱导致与年龄相关的认知衰退，并且与年龄相关的WM变化可能是由于自由基损伤、少突胶质细胞谱系中细胞的退行性变化以及WM内微环境的变化所致。
