Insulin-like growth factor 1 resistance in chronic renal failure

Penal failure is characterized by endocrine and metabolic disorders, some of them being described as a state of resistance to growth hormone (GH) and/or insulin-like growth factor (IGF) 1. There is evidence for a reduced metabolic action of IGF-1 (formerly somatomedin C) in hemodialysis and kidney transplant children and in adults undergoing hemodialysis. Since the development of recombinant human (rh) IGF-1, despite strong metabolic actions, some experimental studies suggest a decrease in metabolic effects of rhIGF-1 in chronic renal failure (CRF). Preliminary reports in adult dialysis patients also stressed the possibility of a resistance to rhIGF-1 metabolic actions. The perturbed IGF-binding protein system in CRF may play an important role in modifying storage and IGF-I delivery to tissues. Also, by analogy with insulin, receptor and postreceptor defects may be involved in this condition, as suggested by rhIGF-1 resistance with aging or in obese Zucker rats. However, rhIGF-1 remains a potent anabolic factor in uremia. Further studies will therefore be necessary to clarify this IGF-1 resistance state. Such knowledge might allow physicians to reduce the amount of rhIGF-1 administered to the patients and improve the anabolic actions of rhIGF-1 during acute and chronic renal failure.