IGF1 and amyotrophic lateral sclerosis: Other identified pathways were previously implicated in brain aging or neurodegenerative disorders and included IGF1, NF-kB, chemokine, cell cycle, nitric oxide, NRF2-mediated oxidative stress response and glucocorticoid receptor signaling and pathways related to neurodegeneration – hypoxia, Huntington's, Parkinson's diseases and amyotrophic lateral sclerosis signaling.