TY - JOUR
T1 - Brain glucose metabolism in adults with ataxia-telangiectasia and their asymptomatic relatives
AU - Volkow, Nora D.
AU - Tomasi, Dardo
AU - Wang, Gene Jack
AU - Studentsova, Yana
AU - Margus, Brad
AU - Crawford, Thomas O.
PY - 2014/6
Y1 - 2014/6
N2 - Ataxia-telangiectasia is a recessive genetic disorder (ATM is the mutated gene) of childhood with severe motor impairments and whereas homozygotes manifest the disorder, heterozygotes are asymptomatic. Structural brain imaging and post-mortem studies in individuals with ataxia-telangiectasia have reported cerebellar atrophy; but abnormalities of motor control characteristic of extrapyramidal dysfunction suggest impairment of broader motor networks. Here, we investigated possible dysfunction in other brain areas in individuals with ataxia-telangiectasia and tested for brain changes in asymptomatic relatives to assess if heterozygocity affects brain function. We used positron emission tomography and 18F-fluorodeoxyglucose to measure brain glucose metabolism (quantified as mol/100 g/min), which serves as a marker of brain function, in 10 adults with ataxia-telangiectasia, 19 non-affected adult relatives (12 siblings, seven parents) and 29 age-matched healthy controls. Statistical parametric mapping and region of interest analyses were used to compare individuals with ataxia-telangiectasia, asymptomatic relatives, and unrelated controls. We found that participants with ataxia-telangiectasia had lower metabolism in cerebellar hemispheres (14, P < 0.001), anterior vermis (40 P < 0.001) and fusiform gyrus (20, P < 0.001) compared with controls or siblings, and lower metabolism in hippocampus (12, P = 0.05) compared with controls, and showed significant intersubject variability (decreases in vermis ranged from 18 to 60). Participants with ataxia-telangiectasia also had higher metabolism in globus pallidus (16, P = 0.05), which correlated negatively with motor performance. Asymptomatic relatives had lower metabolism in anterior vermis (12; P = 0.01) and hippocampus (19; P = 0.002) than controls. Our results indicate that, in addition to the expected decrease in cerebellar metabolism, participants with ataxia-telangiectasia had widespread changes in metabolic rates including hyperactivity in globus pallidus indicative of basal ganglia involvement. Changes in basal ganglia metabolism offer potential insight into targeting strategies for therapeutic deep brain stimulation. Our finding of decreased metabolism in vermis and hippocampus of asymptomatic relatives suggests that heterozygocity influences the function of these brain regions.
AB - Ataxia-telangiectasia is a recessive genetic disorder (ATM is the mutated gene) of childhood with severe motor impairments and whereas homozygotes manifest the disorder, heterozygotes are asymptomatic. Structural brain imaging and post-mortem studies in individuals with ataxia-telangiectasia have reported cerebellar atrophy; but abnormalities of motor control characteristic of extrapyramidal dysfunction suggest impairment of broader motor networks. Here, we investigated possible dysfunction in other brain areas in individuals with ataxia-telangiectasia and tested for brain changes in asymptomatic relatives to assess if heterozygocity affects brain function. We used positron emission tomography and 18F-fluorodeoxyglucose to measure brain glucose metabolism (quantified as mol/100 g/min), which serves as a marker of brain function, in 10 adults with ataxia-telangiectasia, 19 non-affected adult relatives (12 siblings, seven parents) and 29 age-matched healthy controls. Statistical parametric mapping and region of interest analyses were used to compare individuals with ataxia-telangiectasia, asymptomatic relatives, and unrelated controls. We found that participants with ataxia-telangiectasia had lower metabolism in cerebellar hemispheres (14, P < 0.001), anterior vermis (40 P < 0.001) and fusiform gyrus (20, P < 0.001) compared with controls or siblings, and lower metabolism in hippocampus (12, P = 0.05) compared with controls, and showed significant intersubject variability (decreases in vermis ranged from 18 to 60). Participants with ataxia-telangiectasia also had higher metabolism in globus pallidus (16, P = 0.05), which correlated negatively with motor performance. Asymptomatic relatives had lower metabolism in anterior vermis (12; P = 0.01) and hippocampus (19; P = 0.002) than controls. Our results indicate that, in addition to the expected decrease in cerebellar metabolism, participants with ataxia-telangiectasia had widespread changes in metabolic rates including hyperactivity in globus pallidus indicative of basal ganglia involvement. Changes in basal ganglia metabolism offer potential insight into targeting strategies for therapeutic deep brain stimulation. Our finding of decreased metabolism in vermis and hippocampus of asymptomatic relatives suggests that heterozygocity influences the function of these brain regions.
KW - ATM
KW - ataxia telangiectasia mutated
KW - cerebellum
KW - fusiform gyrus
KW - globus pallidus
KW - hippocampus
UR - http://www.scopus.com/inward/record.url?scp=84901411227&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84901411227&partnerID=8YFLogxK
U2 - 10.1093/brain/awu092
DO - 10.1093/brain/awu092
M3 - Article
C2 - 24747834
AN - SCOPUS:84901411227
SN - 0006-8950
VL - 137
SP - 1753
EP - 1761
JO - Brain
JF - Brain
IS - 6
ER -