Obesity is increasingly prevalent and leads to a variety of life-threatening diseases including diabetes, stroke, heart disease and cancers, and has huge economic consequences. Studies on obesity clearly indicate important roles for hypothalamic peptide transmitters in regulating aspects of energy homeostasis. Recently, we have shown that in addition to peptide transmitters, hypothalamic neurons expressing the proopiomelanocortin (POMC) gene, which potently affect energy balance, also release the fast-acting amino acid transmitters GABA and glutamate. The primary goal of this proposal is to test the hypothesis that amino acid transmitters released from POMC neurons play a key role in the regulation of energy balance, and that perturbing GABA and glutamate release from these neurons will affect food intake and body weight. This hypothesis will be tested by 1) determining how GABA and glutamate release from POMC neurons is regulated by fasting and food intake using in situ hybridization and optogenetic stimulation/electrophysiologic techniques. And 2) by determining the result of transiently or persistently disrupting GABA and glutamate release from POMC neurons specifically by using selective knockout approaches, as well as by manipulating POMC neuron activity using designer receptors exclusively activated by designer drugs (DREADD) technology. The consequence of disrupted GABA or glutamate release on energy balance regulation will be determined. Altogether, the results will indicate if POMC neurons affect energy balance circuits via two distinct mechanisms: peptides and amino acid transmitters. It may be that amino acid transmitters in feeding circuits will prove to be viable targets for manipulating energy balance regulation.
Obesity contributes to about 112,000 deaths per year and is the primary reason for over $75 billion in health care expenditures in the United States. A better understanding of how the brain regulates energy balance is a key step towards developing therapeutic approaches to prevent and treat obesity. This study will determine how specific transmitters from neurons known to alter energy balance are contributing to body weight regulation.
|Rau, Andrew R; Hughes, Alexander R; Hentges, Shane T (2018) Various transgenic mouse lines to study proopiomelanocortin cells in the brain stem label disparate populations of GABAergic and glutamatergic neurons. Am J Physiol Regul Integr Comp Physiol 315:R144-R152|
|Fox, Philip D; Hentges, Shane T (2017) Differential Desensitization Observed at Multiple Effectors of Somatic ?-Opioid Receptors Underlies Sustained Agonist-Mediated Inhibition of Proopiomelanocortin Neuron Activity. J Neurosci 37:8667-8677|
|Rau, Andrew R; Hentges, Shane T (2017) The Relevance of AgRP Neuron-Derived GABA Inputs to POMC Neurons Differs for Spontaneous and Evoked Release. J Neurosci 37:7362-7372|
|Jarvie, Brooke C; King, Connie M; Hughes, Alexander R et al. (2017) Caloric restriction selectively reduces the GABAergic phenotype of mouse hypothalamic proopiomelanocortin neurons. J Physiol 595:571-582|
|Cornejo, M P; Hentges, S T; Maliqueo, M et al. (2016) Neuroendocrine Regulation of Metabolism. J Neuroendocrinol 28:|
|Borrow, A P; Stranahan, A M; Suchecki, D et al. (2016) Neuroendocrine Regulation of Anxiety: Beyond the Hypothalamic-Pituitary-Adrenal Axis. J Neuroendocrinol 28:|
|Dennison, Christina S; King, Connie M; Dicken, Matthew S et al. (2016) Age-dependent changes in amino acid phenotype and the role of glutamate release from hypothalamic proopiomelanocortin neurons. J Comp Neurol 524:1222-35|
|Dicken, Matthew S; Hughes, Alexander R; Hentges, Shane T (2015) Gad1 mRNA as a reliable indicator of altered GABA release from orexigenic neurons in the hypothalamus. Eur J Neurosci 42:2644-53|
|Pennock, Reagan L; Hentges, Shane T (2014) Direct inhibition of hypothalamic proopiomelanocortin neurons by dynorphin A is mediated by the ?-opioid receptor. J Physiol 592:4247-56|
|Matsui, Aya; Jarvie, Brooke C; Robinson, Brooks G et al. (2014) Separate GABA afferents to dopamine neurons mediate acute action of opioids, development of tolerance, and expression of withdrawal. Neuron 82:1346-56|
Showing the most recent 10 out of 20 publications