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Assessment of the Metabolic Effects of Isocaloric 2:1 Intermittent Fasting in Mice
Published on: November 27, 2019
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Short-term fasting promotes insulin expression in rat hypothalamus
Tamara B Dakic1, Tanja V Jevdjovic1, Mina I Peric2
1Department for Comparative Physiology and Ecophysiology, Faculty of Biology, Institute for Physiology and Biochemistry, University of Belgrade, Studentski trg 16, 11000, Belgrade, Serbia.
The European Journal of Neuroscience
|May 26, 2017
Summary
Short-term fasting increases hypothalamic insulin expression and content, particularly in specific neurons and ependymal cells. This occurs despite decreased circulating glucose and insulin levels, highlighting complex central nervous system regulation.
Area of Science:
- Neuroendocrinology
- Metabolic Regulation
Background:
- Insulin plays a crucial role in hypothalamic energy homeostasis.
- Understanding central insulin regulation during metabolic shifts is vital.
Purpose of the Study:
- To investigate hypothalamic insulin expression during the early metabolic response to fasting.
- To determine the impact of short-term fasting on central insulin levels and localization.
Main Methods:
- Radioimmunoassay and Western blot for hypothalamic insulin content.
- Quantitative PCR (qPCR) for insulin mRNA expression.
- Immunofluorescence and immunohistochemistry for insulin localization in the hypothalamus.
Main Results:
- Serum glucose and insulin decreased after 6-h fasting, but not in cerebrospinal fluid.
- Hypothalamic insulin mRNA expression and content significantly increased post-fasting.
- Increased insulin immunopositivity was observed in hypothalamic periventricular nucleus neurons and ependymal cells.
Conclusions:
- Short-term fasting upregulates hypothalamic insulin expression and content.
- Fasting-induced changes in hypothalamic insulin are localized to specific neuronal and ependymal cell populations.
- These findings reveal novel complexities in central nervous system insulin regulation during metabolic stress.
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