Hepatic beta-oxidation and carnitine palmitoyltransferase I in neonatal pigs after dietary treatments of clofibric acid, isoproterenol, and medium-chain triglycerides.
A suckling piglet model was used to study nutritional and pharmacologic means of stimulating hepatic fatty acid beta-oxidation. Newborn pigs were fed milk diets containing either long- or medium-chain triglycerides (LCT or MCT). The long-chain control diet was supplemented further with clofibric acid (0.5%) or isoproterenol (40 ppm), and growth was monitored for 10-12 days. Clofibrate increased rates of hepatic peroxisomal and mitochondrial beta-oxidation of [1-(14)C]-palmitate by 60 and 186%, respectively. Furthermore, malonyl-CoA sensitive carnitine palmitoyltransferase (CPT I) activity increased 64% (P < 0.05) in pigs receiving clofibrate. Increased CPT I activity was not congruent with changes in message, as elevated abundance of CPT I mRNA was not detected (P = 0.16) when assessed by qRT-PCR. Neither rates of beta-oxidation nor CPT activities were affected by dietary MCT or by isoproterenol treatment (P > 0.1). Collectively, these findings indicate that clofibrate effectively induced hepatic CPT activity concomitant with increased fatty acid beta-oxidation.
Peffer
Pasha Lyvers
PL
Department of Animal Science, North Carolina State University, Raleigh, NC, USA.
Lin
Xi
X
Odle
Jack
J
D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D002334:Carnitine O-Palmitoyltransferase / Q000378:metabolism*; D002995:Clofibric Acid / Q000494:pharmacology*; D017931:DNA Primers; D018076:DNA, Complementary / Q000096:biosynthesis / Q000235:genetics; D004032:Diet; D005947:Glucose / Q000378:metabolism; D000960:Hypolipidemic Agents / Q000494:pharmacology*; D007202:Indicators and Reagents; D007545:Isoproterenol / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism*; D008930:Mitochondria, Liver / Q000201:enzymology / Q000378:metabolism; D010084:Oxidation-Reduction; D010169:Palmitic Acids / Q000378:metabolism; D020675:Peroxisomes / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013552:Swine; D014280:Triglycerides / Q000494:pharmacology*
D000318:Adrenergic beta-Agonists; D017931:DNA Primers; D018076:DNA, Complementary; D000960:Hypolipidemic Agents; D007202:Indicators and Reagents; D010169:Palmitic Acids; D012333:RNA, Messenger; D014280:Triglycerides; D002995:Clofibric Acid; D002334:Carnitine O-Palmitoyltransferase; D005947:Glucose; D007545:Isoproterenol