TrpC5 Mediates Acute Leptin and Serotonin Effects via Pomc Neurons

Cell Rep. 2017 Jan 17;18(3):583-592. doi: 10.1016/j.celrep.2016.12.072.

Abstract

The molecular mechanisms underlying acute leptin and serotonin 2C receptor-induced hypophagia remain unclear. Here, we show that neuronal and pro-opiomelanocortin (Pomc)-specific loss of transient receptor potential cation 5 (TrpC5) subunits is sufficient to decrease energy expenditure and increase food intake resulting in elevated body weight. Deficiency of Trpc5 subunits in Pomc neurons is also sufficient to block the anorexigenic effects of leptin and serotonin 2C receptor (Ht2Cr) agonists. The loss of acute anorexigenic effects of these receptors is concomitant with a blunted electrophysiological response to both leptin and Ht2Cr agonists in arcuate Pomc neurons. We also demonstrate that the Ht2Cr agonist lorcaserin-induced improvements in glucose and insulin tolerance are blocked by TrpC5 deficiency in Pomc neurons. Together, our results link TrpC5 subunits in the brain with leptin- and serotonin 2C receptor-dependent changes in neuronal activity, as well as energy balance, feeding behavior, and glucose metabolism.

Keywords: diabetes; electrophysiology; glycemia; leptin; lorcaserin; melanocortin; obesity; patch-clamp; serotonin; thermogenesis; transient receptor potential cation channels.

MeSH terms

  • Animals
  • Appetite Depressants / pharmacology
  • Benzazepines / pharmacology
  • Body Weight / drug effects
  • Eating / drug effects
  • Energy Metabolism / drug effects
  • Glucose / metabolism
  • Glucose Tolerance Test
  • Insulin Resistance
  • Leptin / pharmacology*
  • Male
  • Membrane Potentials / drug effects
  • Mice
  • Mice, Knockout
  • Neurons / drug effects*
  • Neurons / metabolism
  • Patch-Clamp Techniques
  • Pro-Opiomelanocortin / metabolism
  • Receptor, Serotonin, 5-HT2C / metabolism
  • Serotonin 5-HT2 Receptor Agonists / pharmacology*
  • TRPC Cation Channels / deficiency
  • TRPC Cation Channels / genetics*
  • Tamoxifen / pharmacology

Substances

  • Appetite Depressants
  • Benzazepines
  • Leptin
  • Receptor, Serotonin, 5-HT2C
  • Serotonin 5-HT2 Receptor Agonists
  • TRPC Cation Channels
  • Trpc5 protein, mouse
  • Tamoxifen
  • lorcaserin
  • Pro-Opiomelanocortin
  • Glucose