Laboratory of Physiological Regulation in Sleeping Mice (PRISM), Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy.
Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell'Emilia, Italy.
Exp Neurol. 2018 Mar;301(Pt A):1-12. doi: 10.1016/j.expneurol.2017.12.006. Epub 2017 Dec 17.
Autosomal dominant leukodystrophy (ADLD) is a rare adult-onset demyelinating disease caused by overexpression of lamin B1, a nuclear lamina filament. Early autonomic dysfunction involving the cardiovascular system before progressive somatic motor dysfunction is a striking feature of most cases of ADLD. In the Plp-FLAG-LMNB1 transgenic mouse model, lamin B1 overexpression in oligodendrocytes elicits somatic motor dysfunction and neuropathology akin to ADLD. Here, we investigate whether Plp-FLAG-LMNB1 mice also develop autonomic cardiovascular dysfunction before or after somatic motor dysfunction. We find that Plp-FLAG-LMNB1 mice have preserved cardiovascular responses to changes in wake-sleep state and ambient temperature and normal indexes of autonomic modulation at 37-42weeks of age despite a progressive somatic motor dysfunction, which includes impairments of walking ability (the ability to walk on a narrow path was impaired in 80% of mice at 34-38weeks of age) and subtle breathing derangements. Only late in the development of the disease phenotype did Plp-FLAG-LMNB1 mice develop a structural deficit of sympathetic noradrenergic fibers, with a 38% decrease in fiber profiles in the kidneys at 44-47weeks of age. We demonstrate that while the Plp-FLAG-LMNB1 mouse model recapitulates the age-dependent motor dysfunction of ADLD, it does not show signs of early autonomic cardiovascular dysfunction, raising the possibility that oligodendrocyte dysfunction may not be sufficient to cause the full spectrum of clinical features present in ADLD.
常染色体显性脑白质营养不良(ADLD)是一种罕见的成人发病脱髓鞘疾病,由核层纤维 lamin B1 的过度表达引起。大多数 ADLD 病例的一个显著特征是,在进行性躯体运动功能障碍之前,早期自主神经功能障碍会涉及心血管系统。在 Plp-FLAG-LMNB1 转基因小鼠模型中,少突胶质细胞中 lamin B1 的过度表达会引发躯体运动功能障碍和类似于 ADLD 的神经病理学。在这里,我们研究 Plp-FLAG-LMNB1 小鼠是否在躯体运动功能障碍之前或之后也会出现自主心血管功能障碍。我们发现,尽管存在进行性躯体运动功能障碍,包括行走能力受损(80%的小鼠在 34-38 周龄时无法在狭窄的小路上行走)和呼吸轻微失调,但 Plp-FLAG-LMNB1 小鼠对睡眠-觉醒状态和环境温度的变化仍保留心血管反应,且自主神经调节的指标正常。仅在疾病表型发展的后期,Plp-FLAG-LMNB1 小鼠才会出现交感去甲肾上腺素纤维的结构性缺陷,其肾脏中的纤维形态减少了 38%,发生在 44-47 周龄时。我们证明,虽然 Plp-FLAG-LMNB1 小鼠模型再现了 ADLD 的年龄依赖性运动功能障碍,但它没有出现早期自主心血管功能障碍的迹象,这表明少突胶质细胞功能障碍可能不足以引起 ADLD 中存在的全部临床特征。