Changes in the ratio of branched-chain to aromatic amino acids affect the secretion of albumin in cultured rat hepatocytes.
The effect of branched-chain amino acids (BCAAs) on the synthesis and secretion of albumin was studied in the primary cultures of rat hepatocytes. The changes in the normal BCAAs/aromatic amino acids (AAAs) ratio reduced the secretion of albumin without altering its mRNA levels. Protein-labeling and pulse-chase experiments showed that a low BCAAs/AAAs ratio reduced the biosynthesis, whereas a high ratio accelerated intracellular decay of albumin. These results suggest that normalization of the BCAAs/AAAs ratio improves albumin synthesis while the excess ratio may induce the degradation of albumin in the cells.
Okuno
M
M
First Department of Internal Medicine, Gifu University School of Medicine, Japan.
Moriwaki
H
H
Kato
M
M
Muto
Y
Y
Kojima
S
S
D000597:Amino Acids, Branched-Chain / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D015870:Gene Expression; D007532:Isoleucine / Q000494:pharmacology; D007700:Kinetics; D007930:Leucine / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010649:Phenylalanine / Q000494:pharmacology*; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D012709:Serum Albumin / Q000096:biosynthesis*; D014443:Tyrosine / Q000494:pharmacology*; D014633:Valine / Q000494:pharmacology
D000597:Amino Acids, Branched-Chain; D012333:RNA, Messenger; D012709:Serum Albumin; D007532:Isoleucine; D014443:Tyrosine; D010649:Phenylalanine; D007930:Leucine; D014633:Valine