Adenosine monophosphate-activated protein kinase involved in variations of muscle glycogen and breast meat quality between lean and fat chickens

• Published in: Journal of animal science Vol. 86; no. 11; pp. 2888 - 2896
• Main Authors: Sibut, V, Le Bihan-Duval, E, Tesseraud, S, Godet, E, Bordeau, T, Cailleau-Audouin, E, Chartrin, P, Duclos, M.J, Berri, C
• Format: Journal Article
• Language: English
• Published: Savoy, IL American Society of Animal Science 01-11-2008; Am Soc Animal Sci
• Subjects: adenosine monophosphate; Adipose Tissue - metabolism; Agricultural sciences; AMP-Activated Protein Kinases - metabolism; Animal production studies; Animal productions; Animals; Biological and medical sciences; Blotting, Western; body fat; Body Weight; breast muscle; breeding lines; carcass composition; chicken meat; chickens; Chickens - metabolism; Chickens - physiology; color; drip loss; enzyme activation; Fluorescence; food analysis; Food industries; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; glycogen; Glycogen - metabolism; Glycogen Phosphorylase - genetics; Glycogen Synthase - genetics; glycolysis; Life Sciences; Meat - standards; Meat and meat product industries; meat composition; meat quality; Pectoralis Muscles - enzymology; Pectoralis Muscles - metabolism; protein kinases; RNA, Messenger - metabolism; selection criteria; Terrestrial animal productions; Vertebrates; meat quality; Adenosine; Farming animal; Poultry; Glycogen; fatness; Meat product; Variations; Protein; Meat; Vertebrata; Meat animals; Quality; Fat; pH; adenosine monophosphate-activated protein kinase; Muscle; Chicken; Mammary gland; Aves; GLYCOGENE; QUALITE DES VIANDES
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/jas.2008-1062

The present study was aimed at evaluating the molecular mechanisms associated with the differences in muscle glycogen content and breast meat quality between 2 experimental lines of chicken divergently selected on abdominal fatness. The glycogen at death (estimated through the glycolytic potential) of the pectoralis major muscle and the quality of the resulting meat were estimated in the 2 lines. The fat chickens exhibited greater glycolytic potential, and in turn lower ultimate pH than the lean chickens. Consequently, the breast meat of fat birds was paler and less colored (i.e., less red and yellow), and exhibited greater drip loss compared with that of lean birds. In relation to these variations, transcription and activation levels of adenosine monophosphate-activated protein kinase (AMPK) were investigated. The main difference observed between lines was a 3-fold greater level of AMPK activation, evaluated through phosphorylation of AMPKα-(Thr¹⁷²), in the muscle of lean birds. At the transcriptional level, data indicated concomitant down- and upregulation for the γ1 and γ2 AMPK subunit isoforms, respectively, in the muscle of lean chickens. Transcriptional levels of enzymes directly involved in glycogen turnover were also investigated. Data showed greater gene expression for glycogen synthase, glycogen phosphorylase, and the γ subunit of phosphorylase kinase in lean birds. Together, these data indicate that selection on body fatness in chicken alters the muscle glycogen turnover and content and consequently the quality traits of the resulting meat. Alterations of AMPK activity could play a key role in these changes.