Changing in Plasma Concentration of a New Form of Creatine

Condition(s) studied

Investigational drug(s) / intervention(s)

New Formulation of Creatine (Creamix): Participants will arrive at the laboratory after an overnight fast (8-10 h), having consumed their last meal no later than 20:00 h on the previous day. Participants will be asked to refrain from creatine supplementation for at least 2-4 weeks prior to the experimental session. During the entire experimental session, no food, caffeine or caloric beverages will be allowed. Water intake will be standardized within predefined limits (250 mL prior to baseline and up to 500 mL during the session). Creamix (10g) will be administered dissolved in water, and no additional fluids will be allowed for at least 20 min following ingestion to minimize variability in gastrointestinal absorption. The exact time of ingestion will be recorded and defined as time zero (T0). Blood samples for plasma analysis will be collected at baseline and at 30, 60, 90, 120, and 180 minutes following creatine administration, in accordance with previously published protocols (Jäger et al., 2007; Harris et al., 2004).

Active Comparator: Creatine Monohydrate: Participants will arrive at the laboratory after an overnight fast (8-10 h), having consumed their last meal no later than 20:00 h on the previous day. Participants will be asked to refrain from creatine supplementation for at least 2-4 weeks prior to the experimental session. During the entire experimental session, no food, caffeine or caloric beverages will be allowed. Water intake will be standardized within predefined limits (250 mL prior to baseline and up to 500 mL during the session). Creatine (5g) will be administered dissolved in water, and no additional fluids will be allowed for at least 20 min following ingestion to minimize variability in gastrointestinal absorption. The exact time of ingestion will be recorded and defined as time zero (T0). Blood samples for plasma analysis will be collected at baseline and at 30, 60, 90, 120, and 180 minutes following creatine administration, in accordance with previously published protocols (Jäger et al., 2007; Harris et al., 2004).

Study summary

Creatine is one of the most popular supplements among athletes. Studies have consistently shown that creatine supplementation increases intramuscular creatine concentrations, improving exercise performance and/or enhancing training adaptations. Research has also indicated that creatine supplementation may improve post-exercise recovery and may help with injury prevention, thermoregulation, rehabilitation, and neuroprotection in cases of concussion and/or spinal cord injury. Several clinical applications of creatine supplementation have also been investigated, particularly in relation to neurodegenerative diseases (e.g., muscular dystrophy, Parkinson's disease, and Huntington's disease), diabetes, osteoarthritis, fibromyalgia, aging, cerebral and cardiac ischemia, adolescent depression, and pregnancy. The most commonly studied form of creatine in the literature is creatine monohydrate. The uptake of creatine first involves its absorption into the bloodstream and subsequently its uptake by target tissues. Plasma creatine levels typically peak about 60 minutes after the oral ingestion of creatine monohydrate. An initial increase in plasma creatine levels, followed by a reduction, can indirectly suggest increased creatine uptake by target tissues. However, in recent years, new formulations of creatine have been developed to improve its solubility, stability, or bioavailability. Therefore, it is of interest to evaluate whether these formulations differ in absorption kinetics from creatine monohydrate, the reference form in the literature. The aim is to compare the blood absorption of a new formulation of creatine (containing Creatine Phosphate, Creatine Pyruvate, Creatine Hydrochloride) with that of traditional creatine monohydrate. It is hypothesized that the new formulation has a pharmacokinetic profile similar to that of creatine monohydrate.

Eligibility

Primary outcome measure(s)

• Total plasma creatine concentration — Blood samples for plasma analysis will be collected at six specific timepoints: baseline (T0) and at 30 (T1), 60 (T2), 90 (T3), 120 (T4), and 180 (T5) minutes following creatine administration.
  Total plasma creatine concentration will be determined using a commercially available enzymatic assay kit (Creatine Assay Kit, Abcam, ab65339), according to the manufacturer's instructions. The assay is based on an enzymatic reaction that converts creatine (and phosphocreatine) into a detectable product, generating a colorimetric signal proportional to creatine concentration. Absorbance will be measured spectrophotometrically at the recommended wavelength. A standard calibration curve will be generated using creatine standards provided with the kit, and sample concentrations will be calculated by interpolation. All plasma samples will be analyzed in duplicate, and quality control samples will be included to ensure assay reliability. Although the assay measures total creatine, the contribution of phosphocreatine in plasma is considered negligible; therefore, measured values will primarily reflect circulating free creatine.

Trial sites (1)

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