Doping control analysis of TB-500, a synthetic version of an active region of thymosin β₄, in equine urine and plasma by liquid chromatography-mass spectrometry.
This study successfully detected TB-500 and its metabolites in equine samples, with significant findings at very low concentrations.
Where it sits
this study against the rest of the tb-500 (thymosin beta-4 fragment) corpusSummary and findings
This study measured the detection of N-acetylated LKKTETQ and its metabolites in equine urine and plasma after administration of TB-500, a synthetic peptide. A single dose of 10 mg of N-acetylated LKKTETQ was administered to horses. The peptide was detected at 0.02 ng/mL in plasma and 0.01 ng/mL in urine.
Abstract
A veterinary preparation known as TB-500 and containing a synthetic version of the naturally occurring peptide LKKTETQ has emerged. The peptide segment (17)LKKTETQ(23) is the active site within the protein thymosin β(4) responsible for actin binding, cell migration and wound healing. The key ingredient of TB-500 is the peptide LKKTETQ with artificial acetylation of the N-terminus. TB-500 is claimed to promote endothelial cell differentiation, angiogenesis in dermal tissues, keratinocyte migration, collagen deposition and decrease inflammation. In order to control the misuse of TB-500 in equine sports, a method to definitely identify its prior use in horses is required. This study describes a method for the simultaneous detection of N-acetylated LKKTETQ and its metabolites in equine urine and plasma samples. The possible metabolites of N-acetylated LKKTETQ were first identified from in vitro studies. The parent peptide and its metabolites were isolated from equine urine or plasma by solid-phase extraction using ion-exchange cartridges, and analysed by liquid chromatography-mass spectrometry (LC/MS). These analytes were identified according to their LC retention times and relative abundances of the major product ions. The peptide N-acetylated LKKTETQ could be detected and confirmed at 0.02 ng/mL in equine plasma and 0.01 ng/mL in equine urine. This method was successful in confirming the presence of N-acetylated LKKTETQ and its metabolites in equine urine and plasma collected from horses administered with a single dose of TB-500 (containing 10mg of N-acetylated LKKTETQ). To our knowledge, this is the first identification of TB-500 and its metabolites in post-administration samples from horses.
Background
The paper addresses the detection of TB-500, a synthetic peptide derived from thymosin β₄, in equine athletes. Prior knowledge indicates that thymosin β₄ is involved in various biological processes, but its use as a performance-enhancing substance raises concerns in sports. This study is significant as it provides methods for detecting TB-500 in biological samples, which is crucial for doping control.
Methods
The study utilized liquid chromatography-mass spectrometry to analyze equine urine and plasma samples for the presence of TB-500. Specific details regarding the population, sample size, dosing, and duration of the study were not reported in the abstract.
Results
Not reported in abstract.
Interpretation
The findings on TB-500 detection contribute to the existing literature on performance-enhancing substances in equine sports. However, without specific numeric results or effect sizes, it is challenging to assess the clinical significance of the detection methods. Potential confounds include the lack of detailed methodology and results, which limits the conclusions that can be drawn about TB-500's impact.
Key findings
- TB-500 detected in equine urine and plasma samples.
- Liquid chromatography-mass spectrometry used for analysis.
- Not reported in abstract.
Limitations
- Not reported in abstract.
- No specific numeric findings provided.
- Lack of detailed methodology in the abstract.