[HTML][HTML] Adiponectin potentiates the acute effects of leptin in arcuate Pomc neurons
Molecular metabolism, 2016•Elsevier
Abstract Objective Adiponectin receptors (AdipoRs) are located on neurons of the
hypothalamus involved in metabolic regulation–including arcuate proopiomelanocortin
(Pomc) and Neuropeptide Y/Agouti-related peptide (NPY/AgRP) neurons. AdipoRs play a
critical role in regulating glucose and fatty acid metabolism by initiating several signaling
cascades overlapping with Leptin receptors (LepRs). However, the mechanism by which
adiponectin regulates cellular activity in the brain remains undefined. Methods In order to …
hypothalamus involved in metabolic regulation–including arcuate proopiomelanocortin
(Pomc) and Neuropeptide Y/Agouti-related peptide (NPY/AgRP) neurons. AdipoRs play a
critical role in regulating glucose and fatty acid metabolism by initiating several signaling
cascades overlapping with Leptin receptors (LepRs). However, the mechanism by which
adiponectin regulates cellular activity in the brain remains undefined. Methods In order to …
Objective
Adiponectin receptors (AdipoRs) are located on neurons of the hypothalamus involved in metabolic regulation – including arcuate proopiomelanocortin (Pomc) and Neuropeptide Y/Agouti-related peptide (NPY/AgRP) neurons. AdipoRs play a critical role in regulating glucose and fatty acid metabolism by initiating several signaling cascades overlapping with Leptin receptors (LepRs). However, the mechanism by which adiponectin regulates cellular activity in the brain remains undefined.
Methods
In order to resolve this issue, we utilized neuron-specific transgenic mouse models to identify Pomc and NPY/AgRP neurons which express LepRs for patch-clamp electrophysiology experiments.
Results
We found that leptin and adiponectin synergistically activated melanocortin neurons in the arcuate nucleus. Conversely, NPY/AgRP neurons were inhibited in response to adiponectin. The adiponectin-induced depolarization of arcuate Pomc neurons occurred via activation of Phosphoinositide-3-kinase (PI3K) signaling, independent of 5′ AMP-activated protein kinase (AMPK) activity. Adiponectin also activated melanocortin neurons at various physiological glucose levels.
Conclusions
Our results demonstrate a requirement for PI3K signaling in the acute adiponectin-induced effects on the cellular activity of arcuate melanocortin neurons. Moreover, these data provide evidence for PI3K as a substrate for both leptin and adiponectin to regulate energy balance and glucose metabolism via melanocortin activity.
Elsevier