SIRT1 and Huntington disease: Mechanistically, mutant huntingtin protein interferes with the CREB-regulated transcription coactivator 1-CREB interaction to repress BDNF transcription, and SIRT1 rescues this defect in vitro and in vivo; this finding suggests a key role of SIRT1 in transcriptional networks in HD brain and offers an opportunity for therapeutic development.767