Insulinlike growth factors

Somatomedins are polypeptide mediators produced in response to growth hormone in the liver, e.g. insulinlike growth factors (IGFs). In particular, IGF-1 is the main mediator of growth hormone action. 

Holmes, M. D., M. N. Poliak, W. C. Willett, and S. E. Hankinson. 2002. Dietary correlates of plasma insulinlike growth factor I and insulin-like growth factor binding protein 3 concentrations. Cancer Epidemiol Biomarkers Prev 11 (9) 852—861. 

As indicated in the discussion of axotomy models, the beneficial influences of trophic factors on motor neurons provide potential therapeutic opportunities. Although previous human trials have been disappointing (for review see [111,112]), adenoassociated viral (AAv) delivery of insulinlike growth factor (IGF)-l to muscle prolongs survival in mutant SOD1 mice [111]. Thus, following intramuscular injection, the retrograde transport of AAV-IGF-1 appears to provide trophic influences to motor neurons. 

Colletti RB, Roberts JD, Devlin JT et al. (1989) Effect of tamoxifen on plasma insulinlike growth factor I in patients with breast cancer. Cancer Res 49 1882-1884... 

Cell Culture-Derived Media-Derived Protein Impurities. Immunoassays can detect low impurity levels (<1 ppm).4 The ELISA is probably one of the most sensitive analytical methods. If bovine serum is used as a media component, then testing should include ELISAs for bovine serum albumin (BSA), bovine transferrin, bovine fetuin, and bovine IgG. Often hormones and growth factors, such as insulin or insulinlike growth factor, are used as media components. ELISAs should be used to detect and quantitate these residuals in the various production steps as well as in the final product. There are commercially available antibodies to most commonly used media components. If proprietary media components are used, then the same investment in time and effort is required for the production of specific antibodies, as described above for host cell impurities. 

Kar S, Baccichet A, Quirion R, Poirier J. 1993b. Entorhinal cortex lesion induces differential responses in [ I] insulinlike growth factor I, [ I] insulin-like growth factor II and [ I] insulin receptor binding sites in the rat hippocampal formation. Neuroscience 55 69-80. 

Receptors for EGF, insulin, insulinlike growth factor-1 (IGF-1) Receptors for NGF, TGF... 

Busch, O., Solheim, E., Bang, G., and Tomes, K. (1996). Guided tissue regeneration and local delivery of insulinlike growth factor I by bioerodible polyorthoester membranes in rat calvarial defects. Int. J. Oral Maxillofac. Implants, 11, 498-505. 

General anabolic effects stimulates release of insulinlike growth factor-I Stimulates milk synthesis Ovary luteinization, progesterone synthesis testis interstitial cell development, androgen synthesis... 

TRH = thyrotropin regulatory hormone PIF = prolactin inhibitory factor GnRH = gonadotropin regulatory hormone IGF-1 = insulinlike growth factor 1 ACTH = corticotropin GH = growth hormone TSH = thyrotropin Prl = prolactin... 

The receptor for insulinlike growth factor-1 (IGF-1) is also similar to the insulin receptor in structure and tyrosine kinase activity. Thus, in this case it is likely that the hormones (insulin and IGF-1) and their receptors have each evolved from common ancestral genes by duplication and divergence. 

Insulin-dependent diabetes mellitus (IDDM) is an example of a metabolic disease under active consideration for inducible gene therapy strategies. In this disorder, inflammatory cytokines have been shown to activate apoptosis in pancreatic beta cells. Experimental studies indicate that expression of insulinlike growth factor-1 (IGF-1) can prevent the cytokine-mediated destruction of beta cells of the pancreas (Giannoukakis et al., 2001). Regulated expression of IGF-1 in human pancreatic islets, to preserve beta cell function, may be a useful approach in the treatment of certain types of diabetes (Demeterco and Levine, 2001). 

Cmzado MC, Risler NR, Miatello RM, Yao G, Schiffrin EL, Touyz RM. 2005. Vascular smooth muscle cell NAD(P)H oxidase activity during the development of hypertension Effect of angiotensin II and role of insulinlike growth factor-1 receptor transactivation. Am J Hypertens 18 81-87. 

Trippel, S. B., Potential role of insulinlike growth factors in fracture healing. Clinical Orthopaedics 355S, S301-313 (1998). 

Implicated in induction and differentiation of cartilaginous tissues during development are a number of growth factors and cytokines, including the TGF-P superfamily. Those implicated include bone morphogenetic protein subfamilies, fibroblast growth factor family, insulinlike growth factor family,... 

---