The effects of ergogenic compounds on myogenic satellite cells.
OBJECTIVE
A series of studies were conducted in which compounds commonly shown to be ergogenic aids for strength athletes if taken orally were evaluated for their ability to directly induce postnatal muscle stem cell proliferation or differentiation/fusion in vitro.


METHODS
Compounds tested were creatine monohydrate, creatine pyruvate, L-glutamine, dehydroepiandrosterone (DHEA), androstenedione, Ma Huang (Ephedra sinensis) extract, and Zhi Shi (Citrus aurantium) extract. Dulbecco's modified eagle medium, supplemented with minimal levels of serum and antibiotics, was used as the initial vehicle for the test compounds. Subsequently, a defined treatment medium termed ITTC was used. Satellite cells were exposed to the test compounds for the indicated times and then evaluated by counting mononucleated and multinucleated (fused) cells.


RESULTS
In serum-containing media, none of the treatment groups displayed increased proliferation over that of the control. However, in the differentiation cultures, 0.10% creatine monohydrate increased differentiation over that of the control cultures. When 0.10% creatine monohydrate was added to defined media formulations, all treatments but one demonstrated increased differentiation over the 0.5% serum control. Time course experiments, which followed the effect of 0.10% creatine monohydrate contained in ITTC defined media over 120 h, suggested that cells exposed to this treatment differentiated earlier and to a greater level than cells exposed to ITTC alone.


CONCLUSIONS
Creatine in the monohydrate form induced differentiation of myogenic satellite cells. Other agents examined did not increase satellite cell proliferation or differentiation. These results provide initial evidence for a mechanistic understanding of observed effects in vivo of increased muscular size and strength from creatine supplementation.
Muscle Biology Laboratory, Department of Animal Sciences, Washington State University, Pullman, WA 99164, USA.
Janet L
JL
Vierck
Deri L
DL
Icenoggle
Luke
L
Bucci
Michael V
MV
Dodson
D000704:Analysis of Variance; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003401:Creatine / Q000494:pharmacology*; D003687:Dehydroepiandrosterone / Q000494:pharmacology*; D005973:Glutamine / Q000494:pharmacology*; D011336:Probability; D032496:Satellite Cells, Skeletal Muscle / Q000187:drug effects* / Q000502:physiology; D012680:Sensitivity and Specificity; D012756:Sheep
D005973:Glutamine; D003687:Dehydroepiandrosterone; D003401:Creatine