Exercise induced regulation of muscular Na+,K+ pump, FXYD1, and NHE1 mRNA and protein expression: importance of training status, intensity, and muscle type

TY - JOUR

T1 - Exercise induced regulation of muscular Na+,K+ pump, FXYD1, and NHE1 mRNA and protein expression: importance of training status, intensity, and muscle type

AU - Rasmussen, Martin Krøyer

AU - Juel, Carsten

AU - Nordsborg, Nikolai Baastrup

N1 - CURIS 2011 5200 021

PY - 2011/5

Y1 - 2011/5

N2 - It is investigated if exercise-induced mRNA changes cause similar protein expression changes of Na+-K+ pump isoforms (α1, α2, β1, β2), FXYD1, and Na+/K+ exchanger (NHE1) in rat skeletal muscle. Expression was evaluated (n = 8 per group) in soleus and extensor digutorum longus after 1 day, 3 days, and 3 wk (5 sessions/wk) of either sprint (4 × 3-min sprint + 1-min rest) or endurance (20 min) running. Two hours after exercise on day 1, no change in protein expression was apparent in either training group or muscle, whereas sprint exercise increased the mRNA of soleus α2 (4.9 ± 0.8-fold; P < 0.05), β2 (13.2 ± 4.4-fold; P < 0.001), and NHE1 (12.0 ± 3.1-fold; P < 0.01). Two hours after sprint exercise, protein expression normalized to control samples was higher on day 3 than day 1 for soleus α1 (41 ± 18% increase vs. 15 ± 8% reduction; P < 0.05), α2 (64 ± 35% increase vs. 37 ± 12% reduction; P < 0.05), β1 (17 ± 21% increase vs. 14 ± 29% reduction; P < 0.05), and FXYD1 (35 ± 16% increase vs. 13 ± 10% reduction; P < 0.05). In contrast, on day 3, soleus α1 (0.1 ± 0.1-fold; P < 0.001), α2 (0.2 ± 0.1-fold; P < 0.001), β1 (0.4 ± 0.1-fold; P < 0.05), and β2-mRNA (2.9 ± 1.7-fold; P < 0.001) expression was lower than after exercise on day 1. After 3 wk of training, no change in protein expression relative to control existed. In conclusion, increased expression of Na+-K+ pump subunits, FXYD1 and NHE1 after 3 days exercise training does not appear to be an effect of increased constitutive mRNA levels. Importantly, sprint exercise can reduce mRNA expression concomitant with increased protein expression.

AB - It is investigated if exercise-induced mRNA changes cause similar protein expression changes of Na+-K+ pump isoforms (α1, α2, β1, β2), FXYD1, and Na+/K+ exchanger (NHE1) in rat skeletal muscle. Expression was evaluated (n = 8 per group) in soleus and extensor digutorum longus after 1 day, 3 days, and 3 wk (5 sessions/wk) of either sprint (4 × 3-min sprint + 1-min rest) or endurance (20 min) running. Two hours after exercise on day 1, no change in protein expression was apparent in either training group or muscle, whereas sprint exercise increased the mRNA of soleus α2 (4.9 ± 0.8-fold; P < 0.05), β2 (13.2 ± 4.4-fold; P < 0.001), and NHE1 (12.0 ± 3.1-fold; P < 0.01). Two hours after sprint exercise, protein expression normalized to control samples was higher on day 3 than day 1 for soleus α1 (41 ± 18% increase vs. 15 ± 8% reduction; P < 0.05), α2 (64 ± 35% increase vs. 37 ± 12% reduction; P < 0.05), β1 (17 ± 21% increase vs. 14 ± 29% reduction; P < 0.05), and FXYD1 (35 ± 16% increase vs. 13 ± 10% reduction; P < 0.05). In contrast, on day 3, soleus α1 (0.1 ± 0.1-fold; P < 0.001), α2 (0.2 ± 0.1-fold; P < 0.001), β1 (0.4 ± 0.1-fold; P < 0.05), and β2-mRNA (2.9 ± 1.7-fold; P < 0.001) expression was lower than after exercise on day 1. After 3 wk of training, no change in protein expression relative to control existed. In conclusion, increased expression of Na+-K+ pump subunits, FXYD1 and NHE1 after 3 days exercise training does not appear to be an effect of increased constitutive mRNA levels. Importantly, sprint exercise can reduce mRNA expression concomitant with increased protein expression.

U2 - 10.1152/ajpregu.00635.2010

DO - 10.1152/ajpregu.00635.2010

M3 - Journal article

C2 - 21325644

SN - 0363-6119

VL - 300

SP - R1209-R1220

JO - American Journal of Physiology: Regulatory, Integrative and Comparative Physiology

JF - American Journal of Physiology: Regulatory, Integrative and Comparative Physiology

IS - 5

ER -