Bone morphogenetic protein 7 (BMP7) reverses obesity and regulates appetite through a central mTOR pathway.

Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA.
The FASEB Journal (Impact Factor: 5.7). 02/2012; 26(5):2187-96. DOI: 10.1096/fj.11-199067
Source: PubMed

ABSTRACT Body weight is regulated by coordinating energy intake and energy expenditure. Transforming growth factor β (TGFβ)/bone morphogenetic protein (BMP) signaling has been shown to regulate energy balance in lower organisms, but whether a similar pathway exists in mammals is unknown. We have previously demonstrated that BMP7 can regulate brown adipogenesis and energy expenditure. In the current study, we have uncovered a novel role for BMP7 in appetite regulation. Systemic treatment of diet-induced obese mice with BMP7 resulted in increased energy expenditure and decreased food intake, leading to a significant reduction in body weight and improvement of metabolic syndrome. Similar degrees of weight loss with reduced appetite were also observed in BMP7-treated ob/ob mice, suggesting a leptin-independent mechanism utilized by BMP7. Intracerebroventricular administration of BMP7 to mice led to an acute decrease in food intake, which was mediated, at least in part, by a central rapamycin-sensitive mTOR-p70S6 kinase pathway. Together, these results underscore the importance of BMP7 in regulating both food intake and energy expenditure, and suggest new therapeutic approaches for obesity and its comorbidities.

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