Training state and fasting-induced PDH regulation in human skeletal muscle

TY - JOUR

T1 - Training state and fasting-induced PDH regulation in human skeletal muscle

AU - Gudiksen, Anders

AU - Bertholdt, Lærke

AU - Stankiewicz, Tomasz

AU - Villesen, Ida

AU - Bangsbo, Jens

AU - Plomgaard, Peter

AU - Pilegaard, Henriette

N1 - CURIS 2018 NEXS 238

PY - 2018/11/1

Y1 - 2018/11/1

N2 - The aim of the present study was to examine the influence of training state on fasting-induced skeletal muscle pyruvate dehydrogenase (PDH) regulation, including PDH phosphorylation. Trained and untrained subjects, matched for skeletal muscle CS activity and OXPHOS protein, fasted for 36 h after receiving a standardized meal. Respiratory exchange ratio (RER) was measured and blood as well as vastus lateralis muscle biopsies were obtained 2, 12, 24, and 36 h after the meal. RER decreased with fasting only in untrained individuals, while PDHa activity decreased from 12 h after the meal in untrained, but only tended to decrease at 36 h in trained. PDH-E1α, PDP1 protein, PDH phosphorylation, and PDH acetylation in skeletal muscle was higher in trained than untrained subjects, but did not change with fasting, while PDK4 protein was higher at 36 h than at 2 h after the meal in both groups. In conclusion, the present results suggest that endurance exercise training modifies the fasting-induced regulation of PDHa activity in skeletal muscle and the substrate switch towards fat oxidation. PDH phosphorylation could not explain the fasting-induced regulation of PDHa activity suggesting other post translational modifications.

AB - The aim of the present study was to examine the influence of training state on fasting-induced skeletal muscle pyruvate dehydrogenase (PDH) regulation, including PDH phosphorylation. Trained and untrained subjects, matched for skeletal muscle CS activity and OXPHOS protein, fasted for 36 h after receiving a standardized meal. Respiratory exchange ratio (RER) was measured and blood as well as vastus lateralis muscle biopsies were obtained 2, 12, 24, and 36 h after the meal. RER decreased with fasting only in untrained individuals, while PDHa activity decreased from 12 h after the meal in untrained, but only tended to decrease at 36 h in trained. PDH-E1α, PDP1 protein, PDH phosphorylation, and PDH acetylation in skeletal muscle was higher in trained than untrained subjects, but did not change with fasting, while PDK4 protein was higher at 36 h than at 2 h after the meal in both groups. In conclusion, the present results suggest that endurance exercise training modifies the fasting-induced regulation of PDHa activity in skeletal muscle and the substrate switch towards fat oxidation. PDH phosphorylation could not explain the fasting-induced regulation of PDHa activity suggesting other post translational modifications.

KW - Acetylation

KW - Exercise training

KW - Fasting

KW - Phosphorylation

KW - Pyruvate dehydrogenase

KW - Skeletal muscle

U2 - 10.1007/s00424-018-2164-6

DO - 10.1007/s00424-018-2164-6

M3 - Journal article

C2 - 29946822

AN - SCOPUS:85049106987

SN - 0031-6768

VL - 470

SP - 1633

EP - 1645

JO - Pflügers Archiv - European Journal of Physiology

JF - Pflügers Archiv - European Journal of Physiology

IS - 11

ER -