Work

Effect of leucine and metabolites of branched chain amino acids on protein turnover in heart.

Year: 1979

Type: article

Abstract: Leucine, but not isoleucine or valine, inhibited protein degradation and accelerated protein synthesis in hearts perfused with buffer that contained glucose (15 mM) and normal plasma levels of other amino acids, except for the branched chain compounds. Products of leucine, isoleucine, and valine metabolism also inhibited protein degradation and stimulated protein synthesis. These compounds included the transamination and decarboxylation products, as well as acetate, acetoacetate, and propionate. In some, but not all instances, inhibition of degradation and acceleration of synthesis were accompanied by an increase in intracellular leucine. When insulin was added to the perfusate, the rate of degradation was reduced by 40%, but addition of leucine was ineffective in the presence of the hormone. Insulin, leucine (2 mM) and a mixture of branched chain amino acids at normal plasma levels increased latency of cathepsin D in hearts that were perfused with buffer containing glucose. A combination of leucine and insulin increased latency more than either substance alone. These studies indicate that leucine as well as a variety of substrates that are oxidized in the citric acid cycle are involved in regulation of protein turnover in heart muscle.

Source: Journal of Biological Chemistry

DOI: 10.1016/s0021-9258(19)86898-9

Authors: B. Chua, D.L. Siehl, H.E. Morgan

Institutions: Pennsylvania State University, Penn State Milton S. Hershey Medical Center

Language: English

Topic: Muscle metabolism and nutrition

Subfield: Nutrition and Dietetics

Field: Nursing

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,430