Mealtime alcohol consumption suppresses skeletal muscle mTORC1 signaling in female mice.

OBJECTIVE:To determine whether alcohol consumed within the meal influences the feeding induced increase in mTORC1 signaling. METHODS:Alcohol provided in the liquid diet was consumed by alcohol naïve, fasted, C57BL/6Hsd female mice and gastrocnemius was collected 1hr after the refeeding. Subsequent experiments determined the extent to which changes in mTORC1 signaling persisted across the day. RESULTS:Compared with control mice, protein synthesis, mTORC1 (Ser2448), 4EBP1 (Ser65), S6K1 (Thr389), rpS6 (Ser240/244), Akt (Thr308), and ULK1 (Ser757) were lower in EtOH. Similar suppressive patterns were observed in the hours following consumption of alcohol containing food throughout the dark cycle. Higher peak blood alcohol concentrations induced by intraperitoneal injection of alcohol extended the time and magnitude of mTORC1 pathway suppression. CONCLUSION:Alcohol administered as part of the meal results in lower skeletal muscle mTORC1 signaling while subsequent models show that alcohol may influence this pathway across the day.