Effect of insulin on whole body protein metabolism in children with type 1 diabetes.
OBJECTIVE
Untreated type 1 diabetes (T1D) is associated with abnormalities in protein metabolism, leading to protein loss. These alterations can be particularly detrimental in children, affecting both normal growth and development. A better understanding of the effects of insulin on protein metabolism in children with T1D is essential for optimizing therapy and minimizing consequences of the disease.The aim of the present review is to outline the effects of insulin on whole body protein metabolism in T1D, focusing particularly on studies in children with T1D.


RESULTS
Whole body protein degradation and amino acid oxidation are enhanced in children with T1D. Insulin reduces the rates at which body proteins are degraded. Whole body protein synthesis is either unaffected or reduced by insulin, even when insulin is administered together with amino acids to prevent insulin-dependent hypoaminoacidemia. Provision of insulin with oral nutrients improves protein balance by inhibiting whole body protein degradation, but does not affect protein synthesis.


CONCLUSIONS
In children with T1D the anticatabolic effects of insulin on whole body protein metabolism are mainly exerted through a reduction in rates at which body proteins are degraded. Nutritional factors enhancing the anabolic effect of insulin need to be further elucidated.
Caso
Giuseppe
G
Department of Surgery, Stony Brook University Medical Center, Stony Brook, New York 11794-8191, USA. giuseppe.caso@stonybrook.edu
McNurlan
Margaret A
MA
D000328:Adult; D000596:Amino Acids / Q000378:metabolism; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000178:diet therapy / Q000188:drug therapy / Q000378:metabolism*; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D007328:Insulin / Q000494:pharmacology* / Q000627:therapeutic use; D010084:Oxidation-Reduction; D011506:Proteins / Q000378:metabolism* / Q000493:pharmacokinetics
D000596:Amino Acids; D007004:Hypoglycemic Agents; D007328:Insulin; D011506:Proteins