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Insulin-like growth factor physiology: what we have learned from human studies
Jeff M P Holly1, Claire M Perks
1School of Clinical Sciences, University of Bristol, IGFs & Metabolic Endocrinology Group, Learning & Research Building, 2nd Floor, Southmead Hospital, Bristol BS10 5NB, UK. Jeff.holly@bristol.ac.uk
Endocrinology and Metabolism Clinics of North America
|June 12, 2012
Summary
Insulin-like growth factors (IGFs) differ from insulin in function, with binding proteins controlling tissue activity. Understanding human IGF physiology requires clinical studies, distinct from experimental models.
Area of Science:
- Endocrinology
- Human Physiology
- Molecular Biology
Background:
- Insulin-like growth factors (IGFs) share structural similarities with insulin but exhibit distinct physiological roles.
- IGF-binding proteins (IGFBPs) possess higher affinity for IGFs than cell surface receptors, mediating precise tissue-specific responses.
- Beyond growth regulation, IGFs are crucial for metabolic homeostasis in humans.
Purpose of the Study:
- To elucidate the fundamental human physiology of IGFs.
- To delineate the differences between human IGF function and experimental models.
- To emphasize the necessity of human clinical studies for comprehensive IGF understanding.
Main Methods:
- Review of existing human clinical data.
- Comparative analysis of IGF physiology in humans versus experimental models.
- Synthesis of current knowledge on IGF-IGFBP interactions.
Main Results:
- IGFs operate distinctly from insulin, primarily regulated by IGFBPs.
- IGF-IGFBP complexes tightly control tissue-specific functions.
- Human IGF physiology presents unique aspects not fully replicable in non-human models.
Conclusions:
- Human IGF physiology is complex, with IGFBPs acting as key regulators.
- Experimental models offer limited insights into human IGF roles, particularly in metabolic regulation.
- Human clinical studies are indispensable for a complete understanding of IGF actions and therapeutic potential.
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