Details

Autor(en) / Beteiligte

• Boussaid-Om Ezzine, S.
• Everaert, N.
• Métayer-Coustard, S.
• Rideau, N.
• Berri, C.
• Joubert, R.
• Temim, S.
• Collin, A.
• Tesseraud, S.

Titel

Effects of heat exposure on Akt/S6K1 signaling and expression of genes related to protein and energy metabolism in chicken ( Gallus gallus) pectoralis major muscle

Ist Teil von

• Comparative Biochemistry and Physiology - Part B: Biochemistry and Molecular Biology, 2010-11, Vol.157 (3), p.281-287

Ort / Verlag

England: Elsevier Inc

Erscheinungsjahr

2010

Quelle

MEDLINE

Beschreibungen/Notizen

• In order to improve understanding of the heat-induced changes in muscle growth, we determined the expression of genes related to protein and energy metabolism in the pectoralis major muscle of chickens. We also explored the protein kinase B (PKB also called Akt)/p70 S6 kinase (S6K1)/S6 pathway that mediates anabolic signals thereby regulating metabolism and hypertrophic/atrophic balance. Four-week-old chickens were exposed to 32 or 22 °C for 1 week. Chickens from both groups were then fasted for 16 h or left fed, and submitted to an oral administration of glucose–arginine to induce an anabolic response (30-min treatment) or left untreated. High ambient temperature and the associated decrease in feed intake modified the expression of certain energy-related genes (e.g. −40% for PGC-1α) and protein metabolism (e.g. about + 80% for atrogin-1), but the expression of several muscle metabolism-related genes considered here was unchanged. The capacity for muscle protein synthesis, i.e. RNA/protein ratio, was reduced in warm conditions (~−20%). Slightly lower activation of S6 induced by glucose–arginine treatment was found at 32 °C compared to 22 °C, which might indicate somewhat lower efficiency of mRNA translation. Analysis of glucose/insulin balance suggested changes in glucose metabolism under heat exposure. However, this remains to be characterized.