The Fat-Brain Axis Enters a New Dimension

Leptin is a hormone produced by fat cells that reduces food intake in humans and rodents by regulating the activity of neurons in the hypothalamus, including those in the arcuate nucleus. In their Perspective, [Elmquist and Flier][1] discuss exciting new research ([ Pinto et al .][2]; [ Bouret et al .][3]) showing that leptin directly affects the activity and synaptic input of arcuate neurons and also stimulates their growth during development. [1]: http://www.sciencemag.org/cgi/content/full/304/5667/63 [2]: http://www.sciencemag.org/cgi/content/short/304/5667/110 [3]: http://www.sciencemag.org/cgi/content/short/304/5667/108