Ny forskning på kreatin

Kreatin drar væske inn i muskelcellen, og blant annet via økt osmotisk trykk settes det i gang en hel kaskade med prosesser som aktiverer dormante satelittceller (som kan smelte sammen med muskelceller og øke potensialet for senere muskelvekst), øker protein- og glykogeninnhold, restitusjon og reparasjon av integriteten til cellene.

I denne studien ble det brukt en såkalt oppladingsfase på 20g per dag i 3 dager etterfulgt av 5g per dag i 7 dager. Det er imidlertid fullt mulig å bare bruke doseringen på 5g per dag - etter omtrent 20 dager vil man allikevel ha fulle lager av kreatin i musklene. Du kan lese mer om kreatin i våre artikler her:

Arkiv over artikler som omhandler kreatin

Physiol Genomics. 2007 Oct 23;

Global and targeted gene expression and protein content in skeletal muscle of young men following short-term creatine monohydrate supplementation.

Safdar A, Yardley NJ, Snow RJ, Melov S, Tarnopolsky MA.

Kinesiology, McMaster University, Hamilton, Canada;
Pediatrics and Medicine, McMaster University, Hamilton, Canada.

Creatine monohydrate (CrM) supplementation has been shown to increase fat-free mass and muscle power output possibly via cell swelling. Little is known about the cellular response to CrM. We investigated the effect of short-term CrM supplementation on global and targeted mRNA expression and protein content in human skeletal muscle. In a randomized, placebo-controlled, crossover, double-blind design, 12 young, healthy, non-obese men were supplemented with either a placebo (PL) or CrM (loading phase, 20 g/d x 3 d; maintenance phase, 5 g/d x 7 d) for 10 days. Following a 28-day washout period, subjects were put on the alternate supplementation for 10 days. Muscle biopsies of the vastus lateralis were obtained and were assessed for mRNA expression (cDNA microarrays + real-time PCR) and protein content (Kinetworks((R)) KPKS 1.0 Protein Kinase screen). CrM supplementation significantly increased fat-free mass, total body water, and body weight of the participants (P < 0.05). Also, CrM supplementation significantly up-regulated (1.3 - 5.0 fold) the mRNA content of genes and protein content of kinases involved in osmosensing and signal transduction, cytoskeleton remodelling, protein and glycogen synthesis regulation, satellite cell proliferation and differentiation, DNA replication and repair, RNA transcription control, and cell survival. We are the first to report this large-scale gene expression in the skeletal muscle with short-term CrM supplementation, a response that suggests changes in cellular osmolarity.