DEFAR - Departamento de Farmácia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530
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Resultados da Pesquisa
Item Evaluation of dermorphin metabolism using zebrafish water tank model and human liver microsomes.(2021) Castro, Juliana de Lima; Pereira, Henrique Marcelo Gualberto; Sousa, Valéria P. de; Martucci, Maria Elvira PoletiBackground: Dermorphin is a heptapeptide with an analgesic potential higher than morphine that does not present the same risk for the development of tolerance. These pharmacological features make dermorphin a potential doping agent in competitive sports and it is already prohibited for racehorses. For athletes, the development of an efficient strategy to monitor for its abuse necessitates an investigation of the metabolism of dermorphin in humans. Methods: Here, human liver microsomes and zebrafish were utilized as model systems of human metabolism to evaluate the presence and kinetics of metabolites derived from dermorphin. Five hours after its administration, the presence of dermorphin metabolites could be detected in both models by liquid chromatography coupled to high- resolution mass spectrometry. Results: Although the two models showed common results, marked differences were also observed in relation to the formed metabolites. Six putative metabolites, based on their exact masses of m/z 479.1915, m/z 501.1733, m/z 495.1657, m/z 223.1073, m/z 180.1017 and m/z 457.2085, are proposed to represent the metabolic pattern of dermor- phin. The major metabolite generated from the administration of dermorphin in both models was YAFG-OH (m/z 457.2085), which is the N-terminal tetrapeptide previously identified from studies on rats. Conclusion: Its extensive characterization and commercial availability suggest that it could serve as a primary target analyte for the detection of dermorphin misuse. The metabolomics approach also allowed the assignment of other confirmatory metabolites.Item A high throughput approach for determination of dermorphin in human urine using LC-HRMS and LC-MS/MS for doping control purposes.(2020) Castro, Juliana de Lima; Martucci, Maria Elvira Poleti; Pereira, Henrique Marcelo Gualberto; Sousa, Valéria P. deDermorphin is a peptide with analgesic actions similar to morphine, but with greater effect and less potential to cause tolerance. The use of dermorphin has been documented in race horses, and its use in humans has already been reported. Considering the potential advantages from the use of dermorphin over morphine, a method to monitor it, and its main metabolite dermorphin (1-4), in humans becomes necessary for doping control. Here, we present two orthogonal methods for this purpose: a high-throughput liquid chromatography coupled to high resolution mass spectrometry (HRMS) as an Initial Testing Procedure and liquid chromatography-tandem mass spectrometry (MS/MS) in the Selected Reaction Monitoring (SRM) acquisition mode for a Confirmation Procedure. For urine samples pre-treatment through a mixed-mode weak cation exchange solid phase extraction (WCX-SPE) emerged as an effective approach to extract peptides from the biological sample. For the HRMS analysis, a Full-MS scan acquisition mode was selected to detect the exact masses of dermorphin and dermorphin (1-4) at m/z 803.37226 and 457.20816, respectively. The SRM method used in the MS/MS confirmation protocol presented high specificity and sensitivity. The selected product ions for dermorphin were 602.2, 202.1 and 574.3 and for dermorphin (1-4) were 207.1, 223.1 and 235.1. Both methods were evaluated for specificity, repeatability, carryover, matrix effects and recovery. No carryover and matrix effects were detected. The Limit of Detection for Initial Testing Procedure and the Limit of Identification for Confirmation Procedure was 2,5 ng/mL. Also, specificity and robustness were acceptable for the application. Together, the developed methods proved to be efficient for the analysis of dermorphin and metabolite for human doping control purpose.