Minute quantities of misfolded mutant superoxide dismutase-1 cause amyotrophic lateral sclerosis.
Mutant forms of superoxide dismutase-1 (SOD1) cause amyotrophic lateral sclerosis (ALS) by an unknown noxious mechanism. Using an antibody against a novel epitope in the G127insTGGG mutation, mutant SOD1 was studied for the first time in spinal cord and brain of an ALS patient. The level was below 0.5% of the SOD1 level in controls. In corresponding transgenic mice the content of mutant SOD1 was also low, although it was enriched in spinal cord and brain compared with other tissues. In the mice the misfolded mutant SOD1 aggregated rapidly and 20% occurred in steady state as detergent-soluble protoaggregates. The misfolded SOD1 and the protoaggregates form, from birth until death, a potentially noxious burden that may induce the motor neuron injury. Detergent-resistant aggregates, as well as inclusions of mutant SOD1 in motor neurons and astrocytes, accumulated in spinal cord ventral horns of the patient and mice with terminal disease. The inclusions and aggregates may serve as terminal markers of long-term assault by misfolded SOD1 and protoaggregates.
Jonsson
P Andreas
PA
Clinical Chemistry, Department of Medical Biosciences, Umeå University Hospital, Sweden.
Ernhill
Karin
K
Andersen
Peter M
PM
Bergemalm
Daniel
D
Brännström
Thomas
T
Gredal
Ole
O
Nilsson
Peter
P
Marklund
Stefan L
SL
D000690:Amyotrophic Lateral Sclerosis / Q000201:enzymology / Q000235:genetics*; D000818:Animals; D000870:Anterior Horn Cells / Q000201:enzymology; D001921:Brain / Q000201:enzymology; D003902:Detergents / Q000494:pharmacology; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D008875:Middle Aged; D009154:Mutation; D010641:Phenotype; D012995:Solubility; D013116:Spinal Cord / Q000201:enzymology; D013482:Superoxide Dismutase / Q000187:drug effects / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D000072105:Superoxide Dismutase-1; D016019:Survival Analysis
D003902:Detergents; C000606290:SOD1 protein, human; C000606291:Sod1 protein, mouse; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1