Pten positively regulates brown adipose function, energy expenditure, and longevity.

Aging in worms and flies is regulated by the PI3K/Akt/Foxo pathway. Here we extend this paradigm to mammals. Pten(tg) mice carrying additional genomic copies of Pten are protected from cancer and present a significant extension of life span that is independent of their lower cancer incidence. Interestingly, Pten(tg) mice have an increased energy expenditure and protection from metabolic pathologies. The brown adipose tissue (BAT) of Pten(tg) mice is hyperactive and presents high levels of the uncoupling protein Ucp1, which we show is a target of Foxo1. Importantly, a synthetic PI3K inhibitor also increases energy expenditure and hyperactivates the BAT in mice. These effects can be recapitulated in isolated brown adipocytes and, moreover, implants of Pten(tg) fibroblasts programmed with Prdm16 and Cebpβ form subcutaneous brown adipose pads more efficiently than wild-type fibroblasts. These observations uncover a role of Pten in promoting energy expenditure, thus decreasing nutrient storage and its associated damage.