Cross‐Talk between the Insulin and Leptin Signaling Systems in Rat Hypothalamus^**

Abstract

We provide evidence for a convergence of leptin and insulin signaling at the level of IRSs-PI 3-kinase and a divergence at the level of Akt. Moreover, our results indicate a direct and positive cross-talk between insulin and leptin at the level of Janus kinase 2 and signal transducer and activator of transcription 3 tyrosine phosphorylation. This mechanism may serve to potentiate the activity of both insulin and leptin pathways and to increase stimulation in physiological processes such as the control of food intake and body weight, which are under the combined control of insulin and leptin.