Insulin-like growth factor targeting

Yee, D. 2006. Targeting insulin-like growth factor pathways. British Journal of Cancer 94(4), 465-468. Zumkeller, W. 2002. The insulin-like growth factor system in hematopoietic cells. Leukaemia and Lymphoma 43(3), 487-491. 

A major food safety issue addressed by the European Union concerns the increase in the level of circulating insulin-like growth factor (IGF-I) in the target animal and its increased excretion in the milk as a consequence of the administration of rBST. There has been epidemiological evidence for an association between circulating IGF-I levels and the relative risk of breast and prostate cancer (34-36). 

Insulin-like growth factor-1 (IGF-1) is a peptide, 7649 Da, with structural homology to proinsulin. It binds preferentially to IGF-1 receptors on the surface of target cells. It has a lower affinity for insulin receptors. The receptors for insulin and IGF-1 share some structural and functional homology. IGF-1 is produced in the liver and in other organs in response to growth hormone action. IGF-1 that reenters the circulation is bound to... 

Serum growth hormone levels were dose-dependently increased after oral and intravenous administration. Moreover, an increase of insulin-like growth factor and serum cortisol was found. Clearly, the pituitary incubation method can only identify compounds which are suitable for further in vivo characterization, because the responses found in test animals at the target organ level are vast different from those found at the pituitary cell level. 

Waly M, Olteanu H, Banerjee R, Choi SW, Mason JB, Parker BS, Sukumar S, Shim S, Sharma A, Benzecry JM, Power-Charnitsky VA, Deth RC. (2004) Activation of methionine synthase by insulin-like growth factor-1 and dopamine a target for neurodevelopmental toxins and thimerosal. Mol Psychiatry 9 358-370. 

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