1. The present study was undertaken to test whether creatine given as a supplement to normal subjects was absorbed, and if continued resulted in an increase in the total creatine pool in muscle. An additional effect of exercise upon uptake into muscle was also investigated. 2. Low doses (1g of creatine monohydrate or less in water) produced only a modest rise in the plasma creatine concentratio...

introduction: this study aimed to evaluate the effect of short-term creatine supplementation on oxidative stress and antioxidant enzymes after six bouts of 50-meter sprint swimming. methods: this quasi-experimental study recruited eight trained female swimmers with the mean age of 25±4.4 years and body mass index (bmi) of 21.8±4.2 kg/m2 to perform six bouts of 50-meter sprint swimming with a 12...

In the myocardium, myosin and creatine kinase isoforms possess different capacities for using O2 and energy-rich phosphates. We studied electrophoretically the distribution of these isoforms in 19 hypertensive rats (two-kidney, one clip model of hypertension) and in age-matched controls. After 6 weeks of hypertension, seven rats were treated with captopril (2 mg/kg daily) for 4 weeks, six were ...

This study investigated the effect of insulin on plasma and muscle creatine accumulation and limb blood flow in humans after creatine administration. Seven men underwent a 300-min euglycemic insulin clamp combined with creatine administration on four separate occasions. Insulin was infused at rates of 5, 30, 55, or 105 mU ⋅ m-2 ⋅ min-1, and on each occasion 12.4 g creatine was administered. Dur...

BACKGROUND The CF transmembrane conductance regulator (CFTR), whose mutations cause cystic fibrosis (CF), depends on ATP for activation and transport function. Availability of ATP in the cell and even more in specific cellular microcompartments often depends on a functional creatine kinase system, which provides the 'energy buffer' phosphocreatine. Creatine supplementation has been shown to inc...

While there have been enormous strides in the understanding of Huntington's disease (HD) pathogenesis, treatment to slow or prevent disease progression remains elusive. We previously reported that dietary creatine supplementation significantly improves the clinical and neuropathological phenotype in transgenic HD mice lines starting at weaning, before clinical symptoms appear. We now report tha...

Doxorubicin is commonly used to treat leukemia, lymphomas, and solid tumors, such as soft tissue sarcomas or breast cancer. A major side effect of doxorubicin therapy is dose-dependent cardiotoxicity. Doxorubicin's effects on cardiac energy metabolism are emerging as key elements mediating its toxicity. We evaluated the effect of doxorubicin on [(14)C]creatine uptake in rat neonatal cardiac myo...

We wanted to determine the optimal method for displaying data for the clinical evaluation of patients with possible acute myocardial infarction. Our primary question was, are the time changes (slopes) of the enzyme tests better predictors of disease than the discrimination values, i.e., the cut-off points? We studied 152 patients with and 114 without a diagnosis of acute myocardial infarction i...

Although a large body of evidence shows that pretreatment of brain tissue with creatine protects against anoxic injury in vitro, only a couple of papers have investigated creatine protection in vivo, and they yielded conflicting results. We attempted to clarify how creatine may be protective in an in vivo model of global cerebral ischemia (GCI). We administered creatine either before of after G...

The iodoacetate-nitrogen-poisoned muscle offers the possibility of studying the stoichiometry of the single muscle twitch since metabolic resynthesis by glycolysis and oxidative phosphorylation are blocked, and there remains as an energy source only the creatine phosphoryltransfer system, creatine phosphate reacting with adenosinediphosphate to give the triphosphate and creatine. It is shown, p...