Decreased expression of peroxisome proliferator-activated receptor alpha and liver fatty acid binding protein after partial hepatectomy of rats and mice.
OBJECTIVE
Marked changes in metabolism, including liver steatosis and hypoglycemia, occur after partial hepatectomy. Peroxisome proliferator-activated receptor alpha (PPAR alpha) is a nuclear hormone receptor that is activated by fatty acids and involved in hepatic fatty acid metabolism and regeneration. Liver fatty acid binding protein (LFABP) is an abundant protein in liver cytosol whose expression is regulated by PPAR alpha. It is involved in fatty acid uptake and diffusion and in PPAR alpha signaling. The aim of this study was to investigate the expression of PPAR alpha and LFABP during liver regeneration.


METHODS
Male Sprague-Dawley rats and male C57 Bl/6 mice were subjected to 2/3 hepatectomy and LFABP and PPAR alpha mRNA and protein levels were measured at different time points after surgery. The effect of partial hepatectomy was followed during 48 h in rats and 72 h in mice.


RESULTS
PPAR alpha mRNA and protein levels were decreased 26 h after hepatectomy of rats. The LFABP mRNA and protein levels paralleled those of PPAR alpha and were also decreased 26 h after hepatectomy. In mice, the mRNA level was decreased after 36 and 72 h after hepatectomy. In this case, LFABP mRNA levels decreased more slowly after partial hepatectomy than in rats.


CONCLUSIONS
A marked decrease in PPAR alpha expression may be important for changed gene expression, e.g. LFABP, and metabolic changes, such as hypoglycemia, during liver regeneration.
Skrtic
Stanko
S
Research Center for Endocrinology and Metabolism, Sahlgrenska Unbiversity Hospital, Göteborg University, SE-413 45 Göteborg, Sweden. stanko.skrtic@medic.gu.se
Carlsson
Linda
L
Ljungberg
Anna
A
Lindén
Daniel
D
Michalik
Liliane
L
Wahli
Walter
W
Oscarsson
Jan
J
D000199:Actins / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D050556:Fatty Acid-Binding Proteins; D015870:Gene Expression; D006003:Glycogen / Q000378:metabolism; D006498:Hepatectomy; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D047493:PPAR alpha / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013045:Species Specificity; D014280:Triglycerides / Q000378:metabolism
D000199:Actins; D001786:Blood Glucose; D002352:Carrier Proteins; D050556:Fatty Acid-Binding Proteins; D047493:PPAR alpha; D012333:RNA, Messenger; D014280:Triglycerides; D006003:Glycogen