Increased IGF mRNA in human skeletal muscle after creatine supplementation. Export

@article{citeulike:4036434, abstract = {PURPOSE: We hypothesized that creatine supplementation would facilitate muscle anabolism by increasing the expression of growth factors and the phosphorylation of anabolic signaling molecules; we therefore tested the responses of mRNA for IGF-I and IGF-II and the phosphorylation state of components of anabolic signaling pathways p70(s6k) and 4E-BP1 to a bout of high-intensity resistance exercise after 5 d of creatine supplementation. METHODS: In a double-blind cross-over design, muscle biopsies were taken from the m. vastus lateralis at rest and 3 and 24 h postexercise in subjects who had taken creatine or placebo for 5 d (21 g x d(-1)). For the first 3 h postexercise, the subjects were fed with a drink containing maltodextrin (0.3 g x kg(-1) body weight x h(-1)) and protein (0.08 g x kg(-1) body weight x h(-1)). RESULTS: After creatine supplementation, resting muscle expressed more mRNA for IGF-I (+30\%, P < 0.05) and IGF-II (+40\%, P = 0.054). Exercise caused an increase by 3 h postexercise in IGF-I (+24\%, P < 0.05) and IGF-II (+48\%, P < 0.05) and by 24 h postexercise in IGF-I (+29\%, P < 0.05), but this effect was not potentiated by creatine supplementation. The phosphorylation states of p70(s6k) and 4E-BP1 were not affected by creatine at rest; phosphorylation of both increased (150-400\%, P < 0.05) to similar levels under placebo and creatine conditions at 3 h postexercise plus feeding. However, the phosphorylation state of 4E-BP1 was higher in the creatine versus placebo condition at 24 h postexercise. CONCLUSION: The increase in lean body mass often reported after creatine supplementation could be mediated by signaling pathway(s) involving IGF and 4E-BP1.}, author = {Deldicque, L. and Louis, M. and Theisen, D. and Nielens, H. and Dehoux, M. and Thissen, J. P. and Rennie, M. J. and Francaux, M.}, citeulike-article-id = {4036434}, citeulike-linkout-0 = {http://view.ncbi.nlm.nih.gov/pubmed/15870625}, citeulike-linkout-1 = {http://www.hubmed.org/display.cgi?uids=15870625}, issn = {0195-9131}, journal = {Medicine and science in sports and exercise}, keywords = {cell\_signaling, creatine, igf}, month = {May}, number = {5}, pages = {731--736}, posted-at = {2009-02-11 19:28:49}, priority = {2}, title = {Increased IGF mRNA in human skeletal muscle after creatine supplementation.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/15870625}, volume = {37}, year = {2005} }

TY - JOUR ID - citeulike:4036434 L3 - citeulike-article-id:4036434 N2 - PURPOSE: We hypothesized that creatine supplementation would facilitate muscle anabolism by increasing the expression of growth factors and the phosphorylation of anabolic signaling molecules; we therefore tested the responses of mRNA for IGF-I and IGF-II and the phosphorylation state of components of anabolic signaling pathways p70(s6k) and 4E-BP1 to a bout of high-intensity resistance exercise after 5 d of creatine supplementation. METHODS: In a double-blind cross-over design, muscle biopsies were taken from the m. vastus lateralis at rest and 3 and 24 h postexercise in subjects who had taken creatine or placebo for 5 d (21 g x d(-1)). For the first 3 h postexercise, the subjects were fed with a drink containing maltodextrin (0.3 g x kg(-1) body weight x h(-1)) and protein (0.08 g x kg(-1) body weight x h(-1)). RESULTS: After creatine supplementation, resting muscle expressed more mRNA for IGF-I (+30%, P < 0.05) and IGF-II (+40%, P = 0.054). Exercise caused an increase by 3 h postexercise in IGF-I (+24%, P < 0.05) and IGF-II (+48%, P < 0.05) and by 24 h postexercise in IGF-I (+29%, P < 0.05), but this effect was not potentiated by creatine supplementation. The phosphorylation states of p70(s6k) and 4E-BP1 were not affected by creatine at rest; phosphorylation of both increased (150-400%, P < 0.05) to similar levels under placebo and creatine conditions at 3 h postexercise plus feeding. However, the phosphorylation state of 4E-BP1 was higher in the creatine versus placebo condition at 24 h postexercise. CONCLUSION: The increase in lean body mass often reported after creatine supplementation could be mediated by signaling pathway(s) involving IGF and 4E-BP1. IS - 5 JF - Medicine and science in sports and exercise SN - 0195-9131 EP - 736 TI - Increased IGF mRNA in human skeletal muscle after creatine supplementation. VL - 37 SP - 731 KW - cell_signaling KW - creatine KW - igf AU - Deldicque, L AU - Louis, M AU - Theisen, D AU - Nielens, H AU - Dehoux, M AU - Thissen, JP AU - Rennie, MJ AU - Francaux, M PY - 2005/05// UR - http://view.ncbi.nlm.nih.gov/pubmed/15870625 ER -