Metabolic progression markers of neurodegeneration in the transgenic G93A-SOD1 mouse model of amyotrophic lateral sclerosis.
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by a progressive loss of motor neurons. Visualizing corresponding metabolic changes in the brain of patients with ALS with proton magnetic resonance spectroscopy ((1)H-MRS) may provide surrogate markers for an early disease detection, for monitoring the progression and for evaluating a treatment response. The primary objective of our study was to evaluate whether modifications in MR metabolite levels occur before clinical disease onset, and whether these changes are directly linked to a distinct spatial progression pattern in the CNS. Therefore, age-dependent alterations in the cerebral and spinal metabolic profile in the mouse model of ALS overexpressing the mutated human G93A-superoxide dismutase 1 (G93A-SOD1) were determined by high-resolution MRS of tissue extracts at 14.1 Tesla. Both non-transgenic mice (control mice) and transgenic mice overexpressing the non-mutated human SOD1 (tg-SOD1) served as controls. In the spinal cord of G93A-SOD1 mice significantly decreased levels of N-acetyl aspartate were already detected 34 days postpartum, i.e. about 60 days before the average disease onset caused by motor neuron decline. In addition, glutamine and gamma-aminobutyric acid concentrations were significantly diminished at Day 75, which is still in the presymptomatic phase of the disease. These metabolic changes were further progressive in the course of the disease and started to involve the brainstem at Day 75. Overall, high-resolution (1)H-MRS allows a sensitive spatial and temporal metabolite profiling in the presymptomatic phase of ALS even before significant neuronal cell loss occurs.
Niessen
Heiko G
HG
Department of Neurology II, Otto-von-Guericke University Magdeburg, Leipziger Str 44, Magdeburg, Germany.
Debska-Vielhaber
Grazyna
G
Sander
Kerstin
K
Angenstein
Frank
F
Ludolph
Albert C
AC
Hilfert
Liane
L
Willker
Wieland
W
Leibfritz
Dieter
D
Heinze
Hans-Jochen
HJ
Kunz
Wolfram S
WS
Vielhaber
Stefan
S
D000367:Age Factors; D000690:Amyotrophic Lateral Sclerosis / Q000150:complications* / Q000175:diagnosis / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D004195:Disease Models, Animal; D018450:Disease Progression; D005973:Glutamine / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D051379:Mice; D008822:Mice, Transgenic; D009154:Mutation; D009410:Nerve Degeneration / Q000175:diagnosis* / Q000209:etiology*; D013482:Superoxide Dismutase / Q000235:genetics*; D013997:Time Factors; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D005973:Glutamine; D001224:Aspartic Acid; D005680:gamma-Aminobutyric Acid; C000179:N-acetylaspartate; C109415:SOD1 G93A protein; D013482:Superoxide Dismutase