SIRT1 and Cowden syndrome 1: A high-fat diet rescues the metabolic, transcriptomic and behavioural phenotypes of a CS mouse model, whereas β-hydroxybutyrate, PARP (poly ADP ribose polymerase) inhibition and NAD+ supplementation can also rescue CS-associated phenotypes through activation of SIRT1, which is involved in cell cycle regulation and response to stressors (Scheibye-Knudsen et al., 2014).