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Updated: Jul 20, 2026
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Isolation of Intermediate Filament Proteins from Multiple Mouse Tissues to Study Aging-associated Post-translational Modifications
Published on: May 18, 2017
Insulin-like growth factors (IGFs): implications for aging
P Cohen1, I Ocrant, P J Fielder
1Department of Pediatrics, Stanford University School of Medicine, California 94305.
Psychoneuroendocrinology
|August 1, 1992
Summary
Insulin-like growth factors (IGF) are vital for growth and development. Age impacts IGF-I levels, with production declining in the elderly due to unknown factors, affecting brain function.
Area of Science:
- Endocrinology
- Neuroscience
- Molecular Biology
Background:
- Insulin-like growth factors (IGF)-I and IGF-II are insulin-homologous peptides with mitogenic and anabolic effects.
- IGF-I levels are influenced by growth hormone (GH) and exhibit significant age-related variations.
- IGF-II is prevalent in the brain, alongside a truncated IGF-I form.
Purpose of the Study:
- To investigate the age-associated changes in IGF production and their underlying causes.
- To explore the role of GH and sex steroids in diminished IGF production in the elderly.
- To understand the mechanisms of IGF action and regulation in the central nervous system.
Main Methods:
- Analysis of IGF-I and IGF-II levels across different age groups.
- Investigation of GH and sex steroid secretion in relation to IGF levels.
- Characterization of IGF receptors and IGF-binding proteins (IGFBPs) in the brain.
Main Results:
- IGF-I levels show a distinct pattern, low in infancy, peaking in puberty, and declining with age.
- The precise factors causing reduced IGF production in the elderly remain undetermined.
- IGF-II is the predominant IGF in the brain, interacting with specific receptors and IGFBPs.
Conclusions:
- IGF-I levels are significantly influenced by age, with a notable decline in older individuals.
- Further research is needed to elucidate the causes of age-related decline in IGF production.
- IGF-binding proteins, particularly IGFBP-2, play a crucial role in regulating IGF bioavailability in the brain.
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