They exert beneficial effects in vivo in models of Parkinson's, Huntington's and Alzheimer's diseases, by inhibiting caspase-1, caspase-3, inducible nitric oxide synthase expression and nitric oxide-mediated toxicity, although a role of their anti-fibrillogenic efficacy cannot be ruled out [28]–[30]. This evidence concerns the gene NOS2 and early-onset autosomal dominant Alzheimer disease.