J Korean Neurol Assoc.  2003 Oct;21(5):521-526.

The Effect of Calcium Modulators on Motoneuron Cells Which Express Mutated Cu / Zn Superoxide Dismutase

• Kim SH
• Kim HJ
• Kim M
• Lee KW

Abstract

BACKGROUND
Intracellular calcium accumulation and dys-regulation is known as one of the mechanism in motor neuronal degeneration with mutations in Cu/Zn superoxide dismutase (SOD-1). METHODS: To investigate the calcium modulators and mutated SOD-1 induced neuronal death, we tested motoneuron-neuroblastoma hybrid (VSC 4.1) cells constitutively expressing human SOD-1 gene with mutations (A4V, G93A) or wild type. Calcium mobilizer through cell membrane (calcium ionophore; A23187) or endogenous calcium releaser (ryanodine, thapsigargin, cyclic ADP-ribose) was treated and cell viabilities were determined by using a 3-(4, 5-dimethylthiazole-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. Apoptotic cell death was monitored by caspase enzyme assay and the Hoescht staining to check the evidence of nuclear fragmentation. RESULTS: Among agents, calcium ionophore and tharpsigargin reduced the level of survival in cells expressing mutant SOD-1. In mutant cells, caspase 3 activity was elevated and showed nuclear fragmentation. This phenomenon was blocked by caspase inhibitor. CONCLUSIONS: Our data suggest that motor neuron degeneration in familial amyotrophic lateral sclerosis with SOD-1 mutation may be mediated by calcium dys-regulation, particularly by exogenous calcium influx and this process induces caspase 3 activity which results in motor neuron death.

Keyword

Amyotrophic lateral sclerosis; Superoxide dismutase; Calcium; Cell death; Apoptosis; Caspase

MeSH Terms

Amyotrophic Lateral Sclerosis
Apoptosis
Calcium*
Caspase 3
Cell Death
Cell Membrane
Cell Survival
Enzyme Assays
Humans
Motor Neurons
Neurons
Superoxide Dismutase*
Superoxides*
Thapsigargin
Calcium
Caspase 3
Superoxide Dismutase
Superoxides
Thapsigargin