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Updated: May 19, 2026
08:06
Assessment of the Metabolic Effects of Isocaloric 2:1 Intermittent Fasting in Mice
Published on: November 27, 2019
Is leptin the parabiotic "satiety" factor? Past and present interpretations
1Department of Physiology, Georgia Health Sciences University, 1120 15th Street, Augusta, GA 30912, USA. ruharris@georgiahealth.edu
Appetite
|August 15, 2012
Summary
Parabiosis studies revealed a circulating signal that regulates fat stores and energy balance. This led to the identification of leptin (OB protein) as a key feedback signal.
Area of Science:
- Endocrinology
- Neuroscience
- Metabolic Research
Background:
- Hervey's 1959 parabiosis studies proposed a feedback signal regulating energy balance.
- Studies involved surgically joining animals to share circulation and observe metabolic responses.
- Parabiosis experiments utilized hypothalamic-lesioned, Zucker, and genetically obese rat models.
Observation:
- Hypothalamic lesions induced obesity in one parabiont, causing the partner to lose fat.
- Overfeeding one parabiont led to fat loss in the non-overfed partner via metabolic adjustments.
- Parabiosis with obese mice suggested a deficiency in their feedback signal production.
Findings:
- The circulating feedback signal regulates adipose tissue mass and energy homeostasis.
- Leptin (OB protein) was identified as a crucial component of this feedback system.
- Evidence suggests additional circulating factors contribute to adipose tissue regulation.
Implications:
- Understanding the leptin-mediated feedback loop is critical for metabolic disease research.
- Further investigation into other circulating factors may reveal novel therapeutic targets.
- This research underpins the neuroendocrine control of body weight and fat storage.
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