Protein metabolism in the extremely low-birth weight infant

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One-step Metabolomics: Carbohydrates, Organic and Amino Acids Quantified in a Single Procedure
09:28

One-step Metabolomics: Carbohydrates, Organic and Amino Acids Quantified in a Single Procedure

Published on: June 25, 2010

S C Kalhan1, S Iben

  • 1Robert Schwartz, MD, Center for Metabolism & Nutrition, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA. sck@po.cwru.edu

Clinics in Perinatology
|February 26, 2000
PubMed

Insights

Very preterm infants exhibit high protein breakdown, unresponsive to nutrient intake. Current interventions for nitrogen accretion in extremely low birth weight (ELBW) infants have not improved growth, possibly due to insufficient calorie and nitrogen delivery.

Area of Science:

  • Neonatal physiology and metabolism
  • Pediatric nutrition and growth

Background:

  • Extensive data exist on nutrient and protein impact on infant growth, plasma amino acids, and nitrogen balance.
  • Limited studies have investigated in vivo protein metabolism dynamics in micropremie or extremely low birth weight (ELBW) infants.

Purpose of the Study:

  • To examine the dynamic aspects of protein metabolism in very preterm infants, including micropremies and ELBW infants.
  • To understand the responsiveness of protein turnover and breakdown to nutrient administration in this vulnerable population.

Main Methods:

  • In vivo examination of protein metabolism dynamics.
  • Analysis of protein turnover and breakdown rates.
  • Assessment of responsiveness to nutrient administration and specific interventions.

Main Results:

  • Very preterm infants demonstrate high rates of protein turnover and breakdown, potentially due to immaturity or illness.
  • High rates of proteolysis show limited responsiveness to nutrient administration.
  • Interventions like insulin, human growth hormone, or glutamine have not enhanced protein accretion or growth.

Conclusions:

  • Protein metabolism in very preterm and ELBW infants is characterized by high proteolysis that is not readily influenced by nutrient intake.
  • Current strategies to promote nitrogen accretion have been ineffective, possibly limited by inadequate calorie and nitrogen delivery.

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