TY - JOUR
T1 - Body weight loss in beef cows
T2 - I. The effect of increased β-oxidation on messenger ribonucleic acid levels of uncoupling proteins two and three and peroxisome proliferator-activated receptor in skeletal muscle
AU - Brennan, K. M.
AU - Michal, J. J.
AU - Ramsey, Jon J
AU - Johnson, K. A.
PY - 2009/9
Y1 - 2009/9
N2 - Twenty-six Angus-cross cows were studied during BW loss (WL) and BW maintenance (WM) to examine the effects of elevated β-oxidation on mRNA levels of NEFA-responsive signaling molecules in skeletal muscle. At the end of the WL and WM sampling periods, muscle biopsies were removed from the biceps femoris and mRNA levels were measured using real-time PCR. In comparison with WM, cows undergoing WL had elevated mRNA levels of carnitine palmitoyltransferase 1 (4.6-fold), fatty acid binding protein 3 (2.0-fold), and acyl-coenzyme A oxidase 1 (2.8-fold), all of which are indicators of β-oxidation. Levels of mRNA of the NEFA-responsive signaling molecules PPAR α, Δ, and γ increased 2.0-fold, 2.2-fold, and 1.84-fold, respectively, during WL. Uncoupling proteins 2 and 3 also had increased mRNA (3.0-fold and 6.0-fold, respectively) during WL, but Western blot analysis found no changes in protein abundance of uncoupling protein 3. Uncoupling protein expression can be directly stimulated by elevated NEFA, potentially to protect cells from damage by lipid oxidation by-products. Thus, an increase in mRNA levels of genes involved in β-oxidation of fatty acids and fatty acid by-products occurs during BW loss in beef cattle. These data support previous findings in nonruminants and suggest that these genes play a role in the same physiological processes in ruminants.
AB - Twenty-six Angus-cross cows were studied during BW loss (WL) and BW maintenance (WM) to examine the effects of elevated β-oxidation on mRNA levels of NEFA-responsive signaling molecules in skeletal muscle. At the end of the WL and WM sampling periods, muscle biopsies were removed from the biceps femoris and mRNA levels were measured using real-time PCR. In comparison with WM, cows undergoing WL had elevated mRNA levels of carnitine palmitoyltransferase 1 (4.6-fold), fatty acid binding protein 3 (2.0-fold), and acyl-coenzyme A oxidase 1 (2.8-fold), all of which are indicators of β-oxidation. Levels of mRNA of the NEFA-responsive signaling molecules PPAR α, Δ, and γ increased 2.0-fold, 2.2-fold, and 1.84-fold, respectively, during WL. Uncoupling proteins 2 and 3 also had increased mRNA (3.0-fold and 6.0-fold, respectively) during WL, but Western blot analysis found no changes in protein abundance of uncoupling protein 3. Uncoupling protein expression can be directly stimulated by elevated NEFA, potentially to protect cells from damage by lipid oxidation by-products. Thus, an increase in mRNA levels of genes involved in β-oxidation of fatty acids and fatty acid by-products occurs during BW loss in beef cattle. These data support previous findings in nonruminants and suggest that these genes play a role in the same physiological processes in ruminants.
KW - β-oxidation
KW - Beef cattle
KW - Peroxisome proliferator-activated receptor
KW - Skeletal muscle
KW - Uncoupling protein
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U2 - 10.2527/jas.2008-1302
DO - 10.2527/jas.2008-1302
M3 - Article
C2 - 19465504
AN - SCOPUS:70249104262
VL - 87
SP - 2860
EP - 2866
JO - Journal of Animal Science
JF - Journal of Animal Science
SN - 0021-8812
IS - 9
ER -