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Orexin: pathways to obesity resistance?
Tammy A Butterick1, Charles J Billington, Catherine M Kotz
1Department of Veterans Affairs, Minneapolis Veterans Affairs Health Care System, 151-Research Service, Geriatric Research Education and Clinical Center (GRECC), One Veterans Drive, Minneapolis, MN, 55417, USA, butte017@umn.edu.
Reviews in Endocrine & Metabolic Disorders
|September 6, 2013
Summary
Orexin A (OXA) may be key to obesity resistance by increasing physical activity and influencing metabolism. This research explores OXA
Area of Science:
- Neuroscience
- Metabolic Research
- Obesity Studies
Background:
- Global obesity rates are rising due to environmental and genetic factors.
- Some individuals exhibit natural resistance to obesity.
- Hypothalamic neuropeptide orexin A (OXA) is implicated in obesity resistance.
Purpose of the Study:
- To investigate the role of orexin A (OXA) in brain mechanisms of obesity resistance.
- To explore central hypothalamic orexin signaling pathways regulating spontaneous physical activity (SPA).
- To identify potential molecular targets for obesity prevention and therapy.
Main Methods:
- Review of existing data from rodent models of obesity and obesity resistance.
- Analysis of animal and in vitro pharmacological studies.
- Hypothesis testing on orexin-mediated regulation of SPA and thermogenesis.
Main Results:
- Increased orexin and/or orexin sensitivity correlates with elevated spontaneous physical activity (SPA).
- Orexin-induced SPA contributes to obesity resistance via non-exercise activity thermogenesis (NEAT).
- A hypoxia-inducible factor 1 alpha (HIF-1α)-dependent pathway is a potential orexin signaling mechanism.
Conclusions:
- Orexin A (OXA) plays a crucial role in promoting obesity resistance.
- Orexin influences obesity resistance through increased SPA and altered hypothalamic neuron metabolism.
- Understanding orexin pathways offers potential for novel obesity interventions.
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