Leptin and mTOR: partners in metabolism and inflammation

Cell Cycle. 2008 Jun 15;7(12):1713-7. doi: 10.4161/cc.7.12.6157. Epub 2008 Jun 16.


Leptin is both a hormone/cytokine that plays a major role in the regulation of feeding and energy expenditure. Beyond its central role in the hypothalamus, leptin modulates peripheral tissues' responses to growth and storage based on nutrient availability, and it regulates the innate and adaptive immune responses. mTOR (mammalian Target of Rapamycin) is a core component of intracellular signaling for cellular growth, mRNA translation, and metabolism. Here, we review recent findings on the cross talk between mTOR and leptin signaling. Important roles for mTOR on leptin signaling have been established both in hypothalamic centers to control food intake and in peripheral cells to regulate lipid metabolism and inflammation. Leptin directly activates resident macrophages to form ADRP-enriched lipid droplets and enhances eicosanoid production via a mechanism that is dependent on activation of the PI3K/mTOR pathway. Leptin-induced mTOR activation may have implications for obesity-related pathophysiological conditions such as diabetes, cardiovascular disease and cancer.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Humans
  • Hypothalamus / metabolism
  • Immunity
  • Inflammation / metabolism*
  • Leptin / physiology*
  • Lipid Metabolism
  • Macrophage Activation
  • Macrophages / immunology
  • Macrophages / metabolism
  • Protein Kinases / metabolism*
  • Signal Transduction
  • TOR Serine-Threonine Kinases


  • Leptin
  • Protein Kinases
  • MTOR protein, human
  • TOR Serine-Threonine Kinases