TY - JOUR
T1 - Physical inactivity affects skeletal muscle insulin signaling in a birth weight-dependent manner
AU - Mortensen, Brynjulf
AU - Friedrichsen, Martin
AU - Andersen, Nicoline Resen
AU - Alibegovic, Amra C
AU - Højbjerre, Lise
AU - Sonne, Mette P
AU - Stallknecht, Bente
AU - Dela, Flemming
AU - Wojtaszewski, Jørgen
AU - Vaag, Allan
N1 - CURIS 2014 NEXS 007
PY - 2014/1
Y1 - 2014/1
N2 - Aims We investigated whether physical inactivity could unmask defects in insulin and AMPK signaling in low birth weight (LBW) subjects. Methods Twenty LBW and 20 normal birth weight (NBW) subjects were investigated using the euglycemic-hyperinsulinemic clamp with excision of skeletal muscle biopsies pre and post 9 days of bed rest. Employing Western blotting, we investigated skeletal muscle Akt, AS160, GLUT4, and AMPK signaling. Results Peripheral insulin action was similar in the two groups and was decreased to the same extent post bed rest. Insulin and AMPK signaling was unaffected by bed rest in NBW individuals. LBW subjects showed decreased insulin-stimulated Akt phosphorylation and increased AMPK α1 and γ3 protein expression post bed rest. Insulin response of AS160 phosphorylation was lower in LBW subjects both pre and post bed rest. Conclusions Bed rest-induced insulin resistance is not explained by impaired muscle insulin or AMPK signaling in subjects with or without LBW. Lower muscle insulin signaling in LBW subjects post bed rest despite similar degree of insulin resistance as seen in controls may to some extent support the idea that LBW subjects are at higher risk of developing type 2 diabetes when being physically inactive.
AB - Aims We investigated whether physical inactivity could unmask defects in insulin and AMPK signaling in low birth weight (LBW) subjects. Methods Twenty LBW and 20 normal birth weight (NBW) subjects were investigated using the euglycemic-hyperinsulinemic clamp with excision of skeletal muscle biopsies pre and post 9 days of bed rest. Employing Western blotting, we investigated skeletal muscle Akt, AS160, GLUT4, and AMPK signaling. Results Peripheral insulin action was similar in the two groups and was decreased to the same extent post bed rest. Insulin and AMPK signaling was unaffected by bed rest in NBW individuals. LBW subjects showed decreased insulin-stimulated Akt phosphorylation and increased AMPK α1 and γ3 protein expression post bed rest. Insulin response of AS160 phosphorylation was lower in LBW subjects both pre and post bed rest. Conclusions Bed rest-induced insulin resistance is not explained by impaired muscle insulin or AMPK signaling in subjects with or without LBW. Lower muscle insulin signaling in LBW subjects post bed rest despite similar degree of insulin resistance as seen in controls may to some extent support the idea that LBW subjects are at higher risk of developing type 2 diabetes when being physically inactive.
U2 - 10.1016/j.jdiacomp.2013.09.002
DO - 10.1016/j.jdiacomp.2013.09.002
M3 - Journal article
C2 - 24120282
SN - 1056-8727
VL - 28
SP - 71
EP - 78
JO - Journal of Diabetes and its Complications
JF - Journal of Diabetes and its Complications
IS - 1
ER -
