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NMDA Receptors in POMC Neurons Connect Exercise With Insulin Sensitivity.
Bryan Portillo1, Eunsang Hwang1, Jason Ajwani1
1Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX.
Diabetes
|October 14, 2024
Summary
Exercise activates proopiomelanocortin (POMC) neurons to improve insulin sensitivity. Deleting NMDA receptors from POMC neurons impairs glucose metabolism and blocks exercise benefits.
Area of Science:
- Neuroscience
- Metabolic Health
- Endocrinology
Background:
- Arcuate proopiomelanocortin (POMC) neuron activity enhances glucose metabolism and reduces appetite.
- Exercise activates POMC neurons, but the role of glutamatergic input is unclear.
Purpose of the Study:
- Investigate the role of NMDA receptors (NMDARs) in POMC neurons in mediating exercise-induced metabolic benefits.
- Determine the impact of NMDAR deletion in POMC neurons on glucose metabolism and insulin sensitivity.
Main Methods:
- Created a mouse model with selective NMDAR deletion in adult POMC neurons.
- Conducted metabolic assessments: body weight, composition, glucose tolerance, and insulin sensitivity tests.
- Examined POMC neuronal activity and insulin sensitivity in response to exercise.
Main Results:
- NMDAR deletion in POMC neurons did not affect body weight or composition.
- Mice lacking NMDARs in POMC neurons showed impaired glucose tolerance and insulin sensitivity.
- Exercise activated POMC neurons and improved insulin sensitivity, an effect abolished by NMDAR deletion.
Conclusions:
- Hypothalamic POMC neurons are crucial for mediating exercise's beneficial effects on glucose metabolism.
- NMDARs in POMC neurons play a key role in linking exercise to improved metabolic health.
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