IGF1 and amyotrophic lateral sclerosis: In support of this hypothesis, it has been shown that levels of phospho-Akt are decreased in motor neurons of spinal cords of ALS [7,8], administration of IGF-1 or VEGF, which activates Akt, prolongs the lifespan of ALS model mice [21], and VEGF-deficient mice show an ALS-like phenotype [22].