Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants

Sue E. Clark, Cheryl A. Karn, Julie A. Ahlrichs, Junying Wang, Catherine A. Leitch, Edward A. Liechty, Scott Denne

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

To determine the effect of parenteral nutrition on the balance and catabolism of leucine (by oxidation) and phenylalanine (by hydroxylation) and to assess any acute changes in proteolysis and/or protein synthesis, leucine and phenylalanine kinetics were measured by stable isotope tracer infusions in nine 32-wk gestation premature infants under both basal conditions and in response to an i.v. infusion of glucose, lipid, and amino acids. Leucine and phenylalanine balance both changed from negative to positive during parenteral nutrition. However, leucine and phenylalanine catabolism were differently affected by parenteral nutrition; the rate of leucine oxidation increased 2-fold, whereas the rate of phenylalanine hydroxylation was unchanged from basal values. Phenylalanine utilization for protein synthesis and leucine utilization for protein synthesis (based on both plasma leucine and α-ketoisocaproic acid enrichments) increased significantly during parenteral nutrition. The endogenous rates of release of leucine (based on plasma leucine enrichment) and phenylalanine (both reflecting proteolysis) were significantly reduced during parenteral nutrition. The endogenous rate of release of leucine (based on α-ketoisocaproic acid enrichment) was slightly but not significantly lower during parenteral nutrition. The substantial increase in leucine oxidation without changes in phenylalanine hydroxylation suggests a possible limitation in the phenylalanine/tyrosine supply during parenteral nutrition. In addition, these results suggest that premature infants respond to parenteral nutrition with acute increases in whole body protein synthesis as well as a probable reduction in proteolysis.

Original languageEnglish
Pages (from-to)568-574
Number of pages7
JournalPediatric Research
Volume41
Issue number4 I
StatePublished - Apr 1997

Fingerprint

Parenteral Nutrition
Phenylalanine
Premature Infants
Leucine
Hydroxylation
Proteolysis
Proteins
Acids
Isotopes
Tyrosine
Lipids
Amino Acids
Glucose
Pregnancy

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health

Cite this

Clark, S. E., Karn, C. A., Ahlrichs, J. A., Wang, J., Leitch, C. A., Liechty, E. A., & Denne, S. (1997). Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants. Pediatric Research, 41(4 I), 568-574.

Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants. / Clark, Sue E.; Karn, Cheryl A.; Ahlrichs, Julie A.; Wang, Junying; Leitch, Catherine A.; Liechty, Edward A.; Denne, Scott.

In: Pediatric Research, Vol. 41, No. 4 I, 04.1997, p. 568-574.

Research output: Contribution to journalArticle

Clark, SE, Karn, CA, Ahlrichs, JA, Wang, J, Leitch, CA, Liechty, EA & Denne, S 1997, 'Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants', Pediatric Research, vol. 41, no. 4 I, pp. 568-574.
Clark SE, Karn CA, Ahlrichs JA, Wang J, Leitch CA, Liechty EA et al. Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants. Pediatric Research. 1997 Apr;41(4 I):568-574.
Clark, Sue E. ; Karn, Cheryl A. ; Ahlrichs, Julie A. ; Wang, Junying ; Leitch, Catherine A. ; Liechty, Edward A. ; Denne, Scott. / Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants. In: Pediatric Research. 1997 ; Vol. 41, No. 4 I. pp. 568-574.
@article{746a7999314447b7bea5ecbc1d7e7afa,
title = "Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants",
abstract = "To determine the effect of parenteral nutrition on the balance and catabolism of leucine (by oxidation) and phenylalanine (by hydroxylation) and to assess any acute changes in proteolysis and/or protein synthesis, leucine and phenylalanine kinetics were measured by stable isotope tracer infusions in nine 32-wk gestation premature infants under both basal conditions and in response to an i.v. infusion of glucose, lipid, and amino acids. Leucine and phenylalanine balance both changed from negative to positive during parenteral nutrition. However, leucine and phenylalanine catabolism were differently affected by parenteral nutrition; the rate of leucine oxidation increased 2-fold, whereas the rate of phenylalanine hydroxylation was unchanged from basal values. Phenylalanine utilization for protein synthesis and leucine utilization for protein synthesis (based on both plasma leucine and α-ketoisocaproic acid enrichments) increased significantly during parenteral nutrition. The endogenous rates of release of leucine (based on plasma leucine enrichment) and phenylalanine (both reflecting proteolysis) were significantly reduced during parenteral nutrition. The endogenous rate of release of leucine (based on α-ketoisocaproic acid enrichment) was slightly but not significantly lower during parenteral nutrition. The substantial increase in leucine oxidation without changes in phenylalanine hydroxylation suggests a possible limitation in the phenylalanine/tyrosine supply during parenteral nutrition. In addition, these results suggest that premature infants respond to parenteral nutrition with acute increases in whole body protein synthesis as well as a probable reduction in proteolysis.",
author = "Clark, {Sue E.} and Karn, {Cheryl A.} and Ahlrichs, {Julie A.} and Junying Wang and Leitch, {Catherine A.} and Liechty, {Edward A.} and Scott Denne",
year = "1997",
month = "4",
language = "English",
volume = "41",
pages = "568--574",
journal = "Pediatric Research",
issn = "0031-3998",
publisher = "Lippincott Williams and Wilkins",
number = "4 I",

}

TY - JOUR

T1 - Acute changes in leucine and phenylalanine kinetics produced by parenteral nutrition in premature infants

AU - Clark, Sue E.

AU - Karn, Cheryl A.

AU - Ahlrichs, Julie A.

AU - Wang, Junying

AU - Leitch, Catherine A.

AU - Liechty, Edward A.

AU - Denne, Scott

PY - 1997/4

Y1 - 1997/4

N2 - To determine the effect of parenteral nutrition on the balance and catabolism of leucine (by oxidation) and phenylalanine (by hydroxylation) and to assess any acute changes in proteolysis and/or protein synthesis, leucine and phenylalanine kinetics were measured by stable isotope tracer infusions in nine 32-wk gestation premature infants under both basal conditions and in response to an i.v. infusion of glucose, lipid, and amino acids. Leucine and phenylalanine balance both changed from negative to positive during parenteral nutrition. However, leucine and phenylalanine catabolism were differently affected by parenteral nutrition; the rate of leucine oxidation increased 2-fold, whereas the rate of phenylalanine hydroxylation was unchanged from basal values. Phenylalanine utilization for protein synthesis and leucine utilization for protein synthesis (based on both plasma leucine and α-ketoisocaproic acid enrichments) increased significantly during parenteral nutrition. The endogenous rates of release of leucine (based on plasma leucine enrichment) and phenylalanine (both reflecting proteolysis) were significantly reduced during parenteral nutrition. The endogenous rate of release of leucine (based on α-ketoisocaproic acid enrichment) was slightly but not significantly lower during parenteral nutrition. The substantial increase in leucine oxidation without changes in phenylalanine hydroxylation suggests a possible limitation in the phenylalanine/tyrosine supply during parenteral nutrition. In addition, these results suggest that premature infants respond to parenteral nutrition with acute increases in whole body protein synthesis as well as a probable reduction in proteolysis.

AB - To determine the effect of parenteral nutrition on the balance and catabolism of leucine (by oxidation) and phenylalanine (by hydroxylation) and to assess any acute changes in proteolysis and/or protein synthesis, leucine and phenylalanine kinetics were measured by stable isotope tracer infusions in nine 32-wk gestation premature infants under both basal conditions and in response to an i.v. infusion of glucose, lipid, and amino acids. Leucine and phenylalanine balance both changed from negative to positive during parenteral nutrition. However, leucine and phenylalanine catabolism were differently affected by parenteral nutrition; the rate of leucine oxidation increased 2-fold, whereas the rate of phenylalanine hydroxylation was unchanged from basal values. Phenylalanine utilization for protein synthesis and leucine utilization for protein synthesis (based on both plasma leucine and α-ketoisocaproic acid enrichments) increased significantly during parenteral nutrition. The endogenous rates of release of leucine (based on plasma leucine enrichment) and phenylalanine (both reflecting proteolysis) were significantly reduced during parenteral nutrition. The endogenous rate of release of leucine (based on α-ketoisocaproic acid enrichment) was slightly but not significantly lower during parenteral nutrition. The substantial increase in leucine oxidation without changes in phenylalanine hydroxylation suggests a possible limitation in the phenylalanine/tyrosine supply during parenteral nutrition. In addition, these results suggest that premature infants respond to parenteral nutrition with acute increases in whole body protein synthesis as well as a probable reduction in proteolysis.

UR - http://www.scopus.com/inward/record.url?scp=0030928870&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030928870&partnerID=8YFLogxK

M3 - Article

C2 - 9098862

AN - SCOPUS:0030928870

VL - 41

SP - 568

EP - 574

JO - Pediatric Research

JF - Pediatric Research

SN - 0031-3998

IS - 4 I

ER -