Gong Zhaoyuan, Bilgel Murat, An Yang, Bergeron Christopher M, Bergeron Jan, Zukley Linda, Ferrucci Luigi, Resnick Susan M, Bouhrara Mustapha
Magnetic Resonance Physics of Aging and Dementia Unit, Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
Brain Aging and Behavior Section, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
Brain Commun. 2024 Nov 16;6(6):fcae412. doi: 10.1093/braincomms/fcae412. eCollection 2024.
Myelin's role in processing speed is pivotal, as it facilitates efficient neural conduction. Its decline could significantly affect cognitive efficiency during ageing. In this work, myelin content was quantified using our advanced MRI method of myelin water fraction mapping. We examined the relationship between myelin water fraction at the time of MRI and retrospective longitudinal change in processing speed among 121 cognitively unimpaired participants, aged 22-94 years, from the Baltimore Longitudinal Study of Aging and the Genetic and Epigenetic Signatures of Translational Aging Laboratory Testing (a mean follow-up duration of 4.3 ± 6.3 years) using linear mixed-effects models, adjusting for demographics. We found that higher myelin water fraction values correlated with longitudinally better-maintained processing speed, with particularly significant associations in several white matter regions. Detailed voxel-wise analysis provided further insight into the specific white matter tracts involved. This research underscores the essential role of myelin in preserving processing speed and highlights its potential as a sensitive biomarker for interventions targeting age-related cognitive decline, thereby offering a foundation for preventative strategies in neurological health.
髓磷脂在处理速度方面的作用至关重要，因为它有助于高效的神经传导。其减少可能会在衰老过程中显著影响认知效率。在这项研究中，我们使用先进的髓磷脂水含量映射磁共振成像（MRI）方法对髓磷脂含量进行了量化。我们在来自巴尔的摩老年纵向研究和转化衰老实验室测试的遗传与表观遗传特征研究的121名22至94岁认知未受损参与者中，使用线性混合效应模型，在调整人口统计学因素后，研究了MRI时的髓磷脂水含量与处理速度的回顾性纵向变化之间的关系（平均随访时长为4.3±6.3年）。我们发现，较高的髓磷脂水含量值与纵向更好维持的处理速度相关，在几个白质区域有特别显著的关联。详细的体素级分析进一步深入了解了所涉及的特定白质束。这项研究强调了髓磷脂在维持处理速度方面的重要作用，并突出了其作为针对与年龄相关认知衰退的干预措施的敏感生物标志物的潜力，从而为神经健康预防策略奠定了基础。
