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Updated: Oct 6, 2025
04:48
Control of Eating Behavior Using a Novel Feedback System
Published on: May 8, 2018
11.2K
Orexin, serotonin, and energy balance
Vijayakumar Mavanji1, Brianna Pomonis1, Catherine M Kotz2,3
1Research Service, Minneapolis VA Health Care System, Minneapolis, Minnesota, USA.
Wires Mechanisms of Disease
|January 13, 2022
Summary
Lateral hypothalamic orexin neurons modulate feeding and spontaneous physical activity (SPA). This review explores the orexin-serotonin axis
Area of Science:
- Metabolic Diseases
- Molecular and Cellular Physiology
- Neuroscience
Background:
- The lateral hypothalamus regulates ingestive behavior and spontaneous physical activity (SPA).
- Orexin neurons in the lateral hypothalamus are key modulators of feeding and SPA.
- These orexin neurons project to the dorsal raphe nucleus (DRN), which contains serotoninergic neurons crucial for energy homeostasis.
Purpose of the Study:
- To review the function of hypothalamic orexin in energy homeostasis.
- To examine the interaction between orexin and DRN serotonin neurons.
- To elucidate the role of the orexin-serotonin axis in regulating food intake, SPA, and energy expenditure (EE).
Main Methods:
- Literature review of studies on orexin, serotonin, and energy balance.
- Analysis of neuroanatomical connections between the lateral hypothalamus and DRN.
- Examination of pharmacological and genetic studies related to orexin and serotonin in obesity.
Main Results:
- Orexin neurons influence feeding and SPA through projections to the DRN.
- The orexin-serotonin axis plays a significant role in regulating food intake, SPA, and EE.
- Serotonin system components (receptors, transporters) are implicated in obesity pathogenesis and treatment.
Conclusions:
- The orexin-serotonin axis is a critical regulator of energy homeostasis.
- Understanding this axis offers potential therapeutic targets for obesity.
- Future research should focus on orexin-serotonin cross-talk and its implications for metabolic diseases.
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