Department of Biosciences, Sri Sathya Sai Institute of Higher Learning, Puttaparthi, Andhra Pradesh, India.
Advanced Imaging Research Center, UT Southwestern Medical Center, Texas, USA.
Neurol India. 2021 Sep-Oct;69(5):1247-1258. doi: 10.4103/0028-3886.329528.
Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by motor, cognitive, and psychiatric abnormalities. Currently, matched analyses of structural and functional differences in the brain from the same study cohort and, specifically, in HD patients from an ethnically diverse Indian population are lacking. Such findings aid in identifying noninvasive and sensitive imaging biomarkers.
The aim of the study was to understand the structural and functional differences between HD and control brain, and presymptomatic and symptomatic HD brain in the Indian population.
Seventeen HD (11 symptomatic HD [S-HD] and six presymptomatic HD [P-HD], with comparable CAG repeats), and 12 healthy controls were examined. Macrostructural (volume), microstructural (diffusivity), and functional (neurochemical levels and glucose metabolism) imaging of the brain was done along with the determination of visual latencies.
HD brain showed increased intercaudate distance; significant subcortical volumetric loss; reduced fractional anisotropy; increased mean, axial, and radial diffusivity; lower levels of total N-acetyl aspartate; elevated total choline levels; and reduced glucose metabolism compared with control brain. Interestingly, compared with P-HD, S-HD patients demonstrated a strong inverse correlation between age at onset and CAG repeat length, and prolonged P100 latency. In addition, caudate and putamen in S-HD brain showed significant volumetric loss and increased diffusivity compared with P-HD brain.
HD brain showed distinct macrostructural, microstructural, and functional differences compared with control brain in the Indian population. Interestingly, patients with S-HD had a significant volumetric loss, increased diffusivity, altered neurochemical profile, and delayed P100 latency compared with P-HD patients. Examining these alterations clinically could aid in monitoring the progression of HD.
亨廷顿病（HD）是一种进行性神经退行性疾病，其特征为运动、认知和精神异常。目前，缺乏来自同一研究队列的脑部结构和功能差异的匹配分析，特别是来自印度多种族人群的 HD 患者。这些发现有助于确定非侵入性和敏感的成像生物标志物。
本研究旨在了解印度人群中 HD 和对照脑以及无症状和有症状 HD 脑之间的结构和功能差异。
共检查了 17 例 HD（11 例有症状 HD[S-HD]和 6 例无症状 HD[P-HD]，CAG 重复数相当）和 12 名健康对照者。对大脑进行了宏观结构（体积）、微观结构（弥散性）和功能（神经化学水平和葡萄糖代谢）成像，同时还测定了视觉潜伏期。
HD 脑表现出内囊间距离增加；明显的皮质下体积损失；各向异性分数降低；平均弥散度、轴向弥散度和径向弥散度增加；总 N-乙酰天冬氨酸水平降低；总胆碱水平升高；葡萄糖代谢减少。有趣的是，与 P-HD 相比，S-HD 患者的发病年龄与 CAG 重复长度呈强烈的负相关，并且 P100 潜伏期延长。此外，与 P-HD 相比，S-HD 患者的尾状核和壳核的体积损失和弥散度增加更为明显。
与对照脑相比，印度人群中 HD 脑显示出明显的宏观结构、微观结构和功能差异。有趣的是，与 P-HD 患者相比，S-HD 患者的体积损失更明显、弥散度更高、神经化学谱改变、P100 潜伏期延长。对这些改变进行临床检查有助于监测 HD 的进展。
