Related Experiment Videos
Plasma carnitine alterations in premature infants receiving various nutritional regimes
R B Smith1, D S Sachan, J Plattsmier
1Department of Nutrition, University of Tennessee, Knoxville.
Insights
Premature infants require exogenous carnitine for adequate plasma levels. Carnitine-free diets decrease carnitine, but levels recover with carnitine-containing nutrition, independent of triglyceride changes.
Area of Science:
- Neonatal Nutrition
- Biochemistry
- Pediatric Metabolism
Background:
- Premature infants have unique nutritional needs.
- Carnitine plays a vital role in fatty acid metabolism.
- Understanding carnitine requirements in preterm infants is crucial for growth and development.
Purpose of the Study:
- To investigate the impact of carnitine-free and carnitine-containing diets on plasma carnitine and triglyceride levels in premature infants.
- To determine if exogenous carnitine supplementation is necessary for maintaining adequate carnitine concentrations in this population.
- To explore the relationship between plasma carnitine and triglyceride concentrations in preterm neonates.
Main Methods:
- Plasma carnitine, carnitine esters, and triglyceride concentrations were measured in 36 appropriate-for-gestational-age infants.
- Infants were categorized into three birth weight groups (<1.0 kg, 1.0-1.51 kg, 1.52-2.5 kg).
- Nutritional interventions included hyperalimentation, intravenous fat emulsion, and various formulas/breastmilk, with blood sampling before and after each intervention.
Main Results:
- Plasma total carnitine and nonesterified carnitine decreased in all groups on carnitine-free diets.
- Carnitine levels increased upon initiation of carnitine-containing diets across all infant groups.
- No inverse relationship was observed between plasma carnitine and triglyceride concentrations.
Conclusions:
- Premature infants generally require exogenous carnitine to maintain plasma carnitine concentrations.
- Carnitine supplementation appears essential for preterm neonates, especially when on carnitine-deficient nutritional regimens.
- The study did not find a correlation between decreased plasma carnitine and elevated triglycerides in this cohort.
Abstract:
Plasma carnitine, carnitine esters, and triglyceride concentrations were determined in 36 appropriate-forgestational-age (AGA) infants at various stages of prematurity throughout hospitalization to determine the effect of a carnitine-free and carnitine-containing diet on plasma carnitine and triglyceride concentrations. The infants were entered into one of three experimental groups based on birth weight: group I less than 1.0 kg; group II 1.0-1.51 kg; and group III 1.52-2.5 kg. Throughout the study subjects were placed on appropriate nutritional regimes which included hyperalimentation (HA), intravenous (iv) fat emulsion (Intralipid), Portagen, Enfamil-24 Premature Formula, Enfamil-20, and breastmilk. Blood samples were drawn from each infant at birth, days 1-5,7 then weekly, also before and after each nutritional intervention to determine carnitine and triglyceride concentrations. Results showed that plasma total carnitine and nonesterified carnitine decreased in all groups when the infants were maintained on a carnitine-free diet (HA, Intralipid, Portagen). In general, the carnitine levels continued to decrease until a carnitine-containing diet was initiated. Once a carnitine-containing diet was begun, plasma total carnitine (TC) and nonesterified carnitine (NEC) levels increased at fairly similar rates in all groups. However, an inverse relationship between carnitine and triglyceride (TG) concentrations were not seen in these infants. This would indicate that most premature infants require exogenous carnitine to maintain the plasma concentration of carnitine. However, a decreased concentration of plasma carnitine was not correlated with an elevated TG level under the conditions of this study.