Physiological Effect of Ghrelin on Body Systems

Figure 8

The CNS ghrelin modulates hypothalamic fatty acid metabolism by activating sirtuin 1 (SIRT1) and AMPK, which in turn stimulates transcription factors essential for NPY/AgRP, which finally affects food intake. The hypothetical molecular step which has not been described is indicated by the red arrow. The question mark indicates a black box in the molecular events triggered after the activation of the GHSR1 and before sirtuin 1. UCP2: uncoupling protein 2; pCREB: phosphorylated cAMP response element-binding protein; FOXO1: forkhead box O1; NPY: neuropeptide Y; AgRP: agouti-related peptide [161].