NPY and MC4R signaling regulate thyroid hormone levels during fasting through both central and peripheral pathways Academic Article uri icon


MeSH Major

  • Fasting
  • Hypothalamo-Hypophyseal System
  • Neuropeptide Y
  • Receptor, Melanocortin, Type 4
  • Signal Transduction
  • Thyroid Hormones


  • Fasting-induced suppression of the hypothalamic-pituitary-thyroid (HPT) axis is an adaptive response to decrease energy expenditure during food deprivation. Previous studies demonstrate that leptin communicates nutritional status to the HPT axis through thyrotropin-releasing hormone (TRH) in the paraventricular nucleus (PVN) of the hypothalamus. Leptin targets TRH neurons either directly or indirectly via the arcuate nucleus through pro-opiomelanocortin (POMC) and agouti-related peptide/neuropeptide Y (AgRP/NPY) neurons. To evaluate the role of these pathways in vivo, we developed double knockout mice that lack both the melanocortin 4 receptor (MC4R) and NPY. We show that NPY is required for fasting-induced suppression of Trh expression in the PVN. However, both MC4R and NPY are required for activation of hepatic pathways that metabolize T(4) during the fasting response. Thus, these signaling pathways play a key role in the communication of fasting signals to reduce thyroid hormone levels both centrally and through a peripheral hepatic circuit.

publication date

  • December 7, 2011



  • Academic Article



  • eng

PubMed Central ID

  • PMC3261758

Digital Object Identifier (DOI)

  • 10.1016/j.cmet.2011.10.009

PubMed ID

  • 22100407

Additional Document Info

start page

  • 780

end page

  • 90


  • 14


  • 6