Abstract: A composition and method for influencing energy metabolism and treating metabolic and other disorders is provided. A terpenoid lactone that is a selective activator of SIRT1 is generally in the form of a terpenoid dilactone having a 5-alkeny-loxy-furan-2- one group, such as strigolactone, GR 24, or another strigolactone analog, and is used as a therapeutic agent in a method for influencing energy metabolism and treating metabolic and other disorders. The terpenoid lactone may be administered as an individual agent or combined with a second compound such as a flavonoid, chalconoid, tannin, or nicotinamide inhibition antagonist.

Abstract: Provided herein are methods for diagnosis and prognosis using polymorphic variants of sirtuins. Such polymorphic may be used, for example, to identify subjects that would be responsive to treatment with a sirtuin modulating compound and/or subjects that are suffering from or susceptible to a disease mediated by a sirtuin. Also provided are methods for determining the predictive value of a sirtuin polymorphic variant, methods for evaluating sirtuin modulating compounds, and methods for determining appropriate dosage and/or treatment regimens for subjects having one or more sirtuin polymorphic variants. Screening methods for identifying sirtuin modulating compounds using polymorphic variants of a sirtuin are also provided.