Dysregulation of intracellular copper homeostasis is common to transgenic mice expressing human mutant superoxide dismutase-1s regardless of their copper-binding abilities.

Over 170 mutations in superoxide dismutase-1 (SOD1) have been linked to amyotrophic lateral sclerosis (ALS). The properties of SOD1 mutants differ considerably including copper-binding abilities. Nevertheless, they cause the same disease phenotype, suggesting a common neurotoxic pathway. We have previously reported that copper homeostasis is disturbed in spinal cords of SOD1(G93A) mice. However, it is unknown whether copper dyshomeostasis is induced by other SOD1 mutants. Using the additional mouse strains SOD1(G127insTGGG), SOD1(G85R), and SOD1(D90A), which express SOD1 mutants with different copper-binding abilities, we show that copper dyshomeostasis is common to SOD1 mutants. The SOD1 mutants shifted the copper trafficking systems toward copper accumulation in spinal cords of the mice. Copper contents bound to the SOD1 active site varied considerably between SOD1 mutants. Still, copper bound to other ligands in the spinal cord were markedly increased in all. Zinc was also increased, whereas there were no changes in magnesium, calcium, aluminum, manganese and iron. Further support for a role of copper dyshomeostasis in ALS was gained from results of pharmacological intervention. Ammonium tetrathiomolybdate (TTM), a copper chelating agent, prolonged survival and slowed the disease progression of SOD1(G93A) mice, even when the treatment was started after the disease onset. TTM markedly attenuated pathology, including the loss of motor neurons and axons, and atrophy of skeletal muscles. Additionally, TTM decreased amounts of SOD1 aggregates. We propose that pharmacological agents that are capable of modulating copper dyshomeostasis, such as TTM, might be beneficial for the treatment of ALS caused by SOD1 mutations.

Tokuda E ，Okawa E ，Watanabe S ，Ono S ，Marklund SL ... -  《-》

Overexpression of metallothionein-I, a copper-regulating protein, attenuates intracellular copper dyshomeostasis and extends lifespan in a mouse model of amyotrophic lateral sclerosis caused by mutant superoxide dismutase-1.

Tokuda E ，Okawa E ，Watanabe S ，Ono S ... -  《-》

Ammonium tetrathiomolybdate delays onset, prolongs survival, and slows progression of disease in a mouse model for amyotrophic lateral sclerosis.

Tokuda E ，Ono S ，Ishige K ，Watanabe S ，Okawa E ，Ito Y ，Suzuki T ... -  《-》

Histological evidence of protein aggregation in mutant SOD1 transgenic mice and in amyotrophic lateral sclerosis neural tissues.

Watanabe M ，Dykes-Hoberg M ，Culotta VC ，Price DL ，Wong PC ，Rothstein JD ... -  《NEUROBIOLOGY OF DISEASE》

Overexpression of Abeta is associated with acceleration of onset of motor impairment and superoxide dismutase 1 aggregation in an amyotrophic lateral sclerosis mouse model.

Li QX ，Mok SS ，Laughton KM ，McLean CA ，Volitakis I ，Cherny RA ，Cheung NS ，White AR ，Masters CL ... -  《AGING CELL》