Mortensen Ole Hartvig, Plomgaard Peter, Fischer Christian P, Hansen Anne K, Pilegaard Henriette, Pedersen Bente Klarlund
Centre of Inflammation and Metabolism, Department of Infectious Diseases, Rigshospitalet 7641, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.
J Appl Physiol (1985). 2007 Nov;103(5):1536-42. doi: 10.1152/japplphysiol.00575.2007. Epub 2007 Aug 9.
We hypothesized that the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) family of transcriptional coactivators (PGC-1alpha, PGC-1beta, and PRC) is differentially regulated by training once daily vs. training twice daily every second day and that this difference might be observed in the acute response to endurance exercise. Furthermore, we hypothesized that expression levels of the PGC-1 family differ with muscular fiber-type composition. Thus, before and after 10 wk of knee extensor endurance training, training one leg once daily and the other leg twice daily every second day, keeping the total amount of training for the legs equal, skeletal muscle mRNA expression levels of PGC-1alpha, PGC-1beta, and PRC were determined in young healthy men (n = 7) in response to 3 h of acute exercise. No significant difference was found between the two legs, suggesting that regulation of the PGC-1 family is independent of training protocol. Training decreased PGC-1beta in both legs, whereas PGC-1alpha was increased, but not significantly, in the leg training once daily. PRC did not change with training. Both PGC-1alpha and PRC were increased by acute exercise both before and after endurance training, whereas PGC-1beta did not change. The mRNA levels of the PGC-1 family were examined in different types of human skeletal muscle (triceps, soleus, and vastus lateralis; n = 7). Only the expression level of PGC-1beta differed and correlated inversely with percentage of type I fibers. In conclusion, there was no difference between training protocols on the acute exercise and training response of the PGC-1 family. However, training caused a decrease in PGC-1beta mRNA levels.
我们推测，转录共激活因子过氧化物酶体增殖物激活受体γ共激活因子-1（PGC-1）家族（PGC-1α、PGC-1β和PRC）在每天训练一次与每隔一天训练两次的情况下受到不同调节，且这种差异可能在耐力运动的急性反应中观察到。此外，我们推测PGC-1家族的表达水平因肌肉纤维类型组成而异。因此，在对年轻健康男性（n = 7）进行10周的伸膝耐力训练前后，一条腿每天训练一次，另一条腿每隔一天训练两次，使双腿的训练总量相等，然后测定在3小时急性运动后PGC-1α、PGC-1β和PRC的骨骼肌mRNA表达水平。两条腿之间未发现显著差异，表明PGC-1家族的调节与训练方案无关。训练使双腿的PGC-1β降低，而每天训练一次的腿中PGC-1α升高，但不显著。PRC不随训练而变化。在耐力训练前后，急性运动均使PGC-1α和PRC升高，而PGC-1β未发生变化。在不同类型的人体骨骼肌（肱三头肌、比目鱼肌和股外侧肌；n = 7）中检测了PGC-1家族的mRNA水平。只有PGC-1β的表达水平存在差异，且与I型纤维的百分比呈负相关。总之，训练方案在PGC-1家族的急性运动和训练反应方面没有差异。然而，训练导致PGC-1β mRNA水平降低。
