GABAergic disinhibition from the BNST to PNOCARC neurons promotes HFD-induced hyperphagia
Tamara Sotelo-Hitschfeld, Marielle Minère, Paul Klemm, Diba Borgmann, Daria Wnuk-Lipinski, Alexander Jaïs, Xianglian Jia, Svenja Corneliussen, Peter Kloppenburg, Henning Fenselau, Jens C. Brüning
Abstract
Activation of prepronociceptin (PNOC)-expressing neurons in the arcuate nucleus (ARC) promotes high-fat-diet (HFD)-induced hyperphagia. In turn, PNOC ARC neurons can inhibit the anorexic response of proopiomelanocortin (POMC) neurons. Here, we validate the necessity of PNOC ARC activity for HFD-induced inhibition of POMC neurons in mice and find that PNOC ARC -neuron-dependent inhibition of POMC neurons is mediated by gamma-aminobutyric acid (GABA) release. When monitoring individual PNOC ARC neuron activity via Ca 2+ imaging, we find a subpopulation of PNOC ARC neurons that is inhibited upon gastrointestinal calorie sensing and disinhibited upon HFD feeding. Combining retrograde rabies tracing and circuit mapping, we find that PNOC neurons from the bed nucleus of the stria terminalis (PNOC BNST ) provide inhibitory input to PNOC ARC neurons, and this inhibitory input is blunted upon HFD feeding. This work sheds light on how an increase in caloric content of the diet can rewire a neuronal circuit, paving the way to overconsumption and obesity development.