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Insulin-like growth factor I and insulin and their abuse in sport

Ioulietta Erotokritou-Mulligan1, Richard I G Holt

  • 1Developmental Origins of Health and Disease Division, University of Southampton, School of Medicine, Southampton, Hampshire, UK. I.E.Mulligan@soton.ac.uk

Endocrinology and Metabolism Clinics of North America
|February 4, 2010
PubMed

It is believed that insulin and insulin-like growth factor I (IGF-I) are abused by professional athletes, either alone or in combination with growth hormone (GH) and anabolic steroids. The recent introduction of IGF-I to clinical practice is likely to increase its availability and abuse. Insulin and IGF-I work together with GH to control the supply of nutrients to tissues in the fasted and fed state. The actions of insulin and IGF-I that may enhance performance include increased protein anabolism and glucose uptake and storage. The detection of IGF-I and insulin abuse is challenging. There are established mass spectrometry methods for insulin analogs. The feasibility of using GH-dependent markers to detect IGF-I use is being assessed.

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