Effect of alanyl-glutamine on leucine and protein metabolism in endotoxemic rats
Language English Country United States Media print
Document type Journal Article, Research Support, Non-U.S. Gov't
- MeSH
- Alanine administration & dosage pharmacology MeSH
- Dipeptides administration & dosage metabolism MeSH
- Endotoxemia drug therapy MeSH
- Glutamine administration & dosage pharmacology MeSH
- Glycine administration & dosage pharmacology MeSH
- Infusions, Intravenous MeSH
- Muscle, Skeletal metabolism MeSH
- Rats MeSH
- Leucine drug effects metabolism MeSH
- Rats, Wistar MeSH
- Proteins drug effects metabolism MeSH
- Amino Acids, Branched-Chain metabolism MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Alanine MeSH
- alanylglutamine MeSH Browser
- Dipeptides MeSH
- Glutamine MeSH
- Glycine MeSH
- Leucine MeSH
- Proteins MeSH
- Amino Acids, Branched-Chain MeSH
BACKGROUND: Branched-chain amino acids (BCAA; valine, leucine, and isoleucine) have a regulatory effect on protein metabolism and are the main donor for synthesis of alanine and glutamine in the skeletal muscle. This study was performed to investigate whether exogenous alanine or glutamine would affect leucine and protein metabolism in intact and endotoxemic rats. METHODS: Rats were injected with endotoxin of Salmonella enteritidis or saline. Thirty minutes later, the effects of endotoxemia and L-alanyl-L-glutamine (AG) on leucine and protein metabolism were evaluated using a primed constant infusion of [1-14C]leucine, endotoxin, and AG (200 mg/mL) solution or an infusion of [1-14C]leucine without endotoxin or AG. The specificity of the effect of exogenous alanine and glutamine was evaluated by a single infusion of alanine, glutamine, and glycine in a separate study. RESULTS: Endotoxin treatment induced more negative net protein balance caused mainly by an increase in whole-body proteolysis. Protein synthesis increased in kidneys, colon, and spleen, while a decrease was observed in skeletal muscle. The impressive effects of AG were the decrease in plasma branched-chain amino acid (BCAA) levels, decrease in leucine oxidized fraction, and improvement of protein balance associated with a decrease in whole-body proteolysis. Similar changes in leucine and protein metabolism were induced by infusion of alanine or glutamine but not by infusion of glycine. CONCLUSIONS: IV administration of alanine or glutamine improves protein balance and decreases leucine oxidized fraction in postabsorptive state and in endotoxemia. Decreased proteolysis is the main cause of decreased plasma BCAA levels after AG treatment.
References provided by Crossref.org
Aspartic Acid in Health and Disease
The dose-dependent effects of endotoxin on protein metabolism in two types of rat skeletal muscle
Muscle wasting in animal models of severe illness
