Hypoxic induction of vascular endothelial growth factor is impaired in the spinal cord of the mice with mutant human SOD1 gene

We examined the induction of vascular endothelial growth factor (VEGF) in the G93A superoxide dismutase (SOD)1-mutant mice exposed to systemic hypoxia. Generally, baseline expression of VEGF in the spinal cord was increased in the SOD1-mutant mice compared with wild-type littermates. VEGF expression in the mutant mice was hardly induced by hypoxia, in contrast to the wild-type littermates where approximately 9-fold increase in VEGF expression was observed, indicating that the response of VEGF to hypoxia is impaired in the SOD1-mutant mice. Our results suggest that the impaired response to hypoxia might be part of precipitating factors for motor neuron death in the SOD1-mutant mice.