PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of bmcvetresBioMed Centralsearchsubmit a manuscriptregisterthis articleBMC Veterinary Research
 
BMC Vet Res. 2012; 8: 28.
Published online Mar 14, 2012. doi:  10.1186/1746-6148-8-28
PMCID: PMC3361467
Expression of genes involved in hepatic carnitine synthesis and uptake in dairy cows in the transition period and at different stages of lactation
Gloria Schlegel,1 Janine Keller,1 Frank Hirche,2 Stefanie Geißler,2 Frieder J Schwarz,3 Robert Ringseis,1 Gabriele I Stangl,2 and Klaus Edercorresponding author1
1Institute of Animal Nutrition and Nutrition Physiology, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 26-32, D-35392 Giessen, Germany
2Institute of Agricultural and Nutritional Sciences, Martin-Luther-Universität Halle, Von-Danckelmann-Platz 2, D-06120 Halle, Saale, Germany
3Animal Nutrition, Technische Universität München, Liesel-Beckmann-Strasse 6, D-85354 Freising, Germany
corresponding authorCorresponding author.
Gloria Schlegel: gloria.schlegel/at/ernaehrung.uni-giessen.de; Janine Keller: janine.keller/at/ernaehrung.uni-giessen.de; Frank Hirche: frank.hirche/at/landw.uni-halle.de; Stefanie Geißler: stefanie.geissler/at/landw.uni-halle.de; Frieder J Schwarz: schwarzf/at/wzw.tum.de; Robert Ringseis: robert.ringseis/at/ernaehrung.uni-giessen.de; Gabriele I Stangl: gabriele.stangl/at/landw.uni-halle.de; Klaus Eder: klaus.eder/at/ernaehrung.uni-giessen.de
Received October 26, 2011; Accepted March 14, 2012.
Abstract
Background
In rodents and pigs, it has shown that carnitine synthesis and uptake of carnitine into cells are regulated by peroxisome proliferator-activated receptor α (PPARA), a transcription factor which is physiologically activated during fasting or energy deprivation. Dairy cows are typically in a negative energy balance during early lactation. We investigated the hypothesis that genes of carnitine synthesis and uptake in dairy cows are enhanced during early lactation.
Results
mRNA abundances of PPARA and some of its classical target genes and genes involved in carnitine biosynthesis [trimethyllysine dioxygenase (TMLHE), 4-N-trimethylaminobutyraldehyde dehydrogenase (ALDH9A1), γ-butyrobetaine dioxygenase (BBOX1)] and uptake of carnitine [novel organic cation transporter 2 (SLC22A5)] as well as carnitine concentrations in liver biopsy samples of 20 dairy cows in late pregnancy (3 wk prepartum) and early lactation (1 wk, 5 wk, 14 wk postpartum) were determined. From 3 wk prepartum to 1 wk postpartum, mRNA abundances of PPARΑ and several PPARΑ target genes involved in fatty acid uptake, fatty acid oxidation and ketogenesis in the liver were strongly increased. Simultaneously, mRNA abundances of enzymes of carnitine synthesis (TMLHE: 10-fold; ALDH9A1: 6-fold; BBOX1: 1.8-fold) and carnitine uptake (SLC22A5: 13-fold) and the concentration of carnitine in the liver were increased from 3 wk prepartum to 1 wk postpartum (P < 0.05). From 1 wk to 5 and 14 wk postpartum, mRNA abundances of these genes and hepatic carnitine concentrations were declining (P < 0.05). There were moreover positive correlations between plasma concentrations of non-esterified fatty acids (NEFA) and hepatic carnitine concentrations at 1 wk, 5 wk and 14 wk postpartum (P < 0.05).
Conclusions
The results of this study show for the first time that the expression of hepatic genes of carnitine synthesis and cellular uptake of carnitine is enhanced in dairy cows during early lactation. These changes might provide an explanation for increased hepatic carnitine concentrations observed in 1 wk postpartum and might be regarded as a physiologic means to provide liver cells with sufficient carnitine required for transport of excessive amounts of NEFA during a negative energy balance.
Articles from BMC Veterinary Research are provided here courtesy of
BioMed Central