A burst of fenoterol excretion during the recovery of a weight loss protocol.

Autor: Cheibub AM; Laboratory of Protein Biochemistry,The Federal University of State of Rio de Janeiro (UNIRIO), Brazil. Electronic address: anamariacheibub@gmail.com., Muniz-Santos R; Laboratory of Protein Biochemistry,The Federal University of State of Rio de Janeiro (UNIRIO), Brazil. Electronic address: renanmuniz@edu.unirio.br., Murgu M; Waters Corporation, São Paulo, Brazil. Electronic address: michael_murgu@waters.com., Avezum J; Bichara e Motta Advogados, Rio de Janeiro, Brazil. Electronic address: juliana.avezum@bicharaemotta.com.br., Abidão-Neto B; Bichara e Motta Advogados, Rio de Janeiro, Brazil. Electronic address: bichara@bicharaemotta.com.br., Cameron LC; Laboratory of Protein Biochemistry,The Federal University of State of Rio de Janeiro (UNIRIO), Brazil. Electronic address: cameron@unirio.br.
Jazyk: angličtina
Zdroj: Journal of pharmaceutical and biomedical analysis [J Pharm Biomed Anal] 2023 Feb 20; Vol. 225, pp. 115209. Date of Electronic Publication: 2022 Dec 22.
DOI: 10.1016/j.jpba.2022.115209
Abstrakt: Fenoterol is a sympathomimetic β2 receptor agonist primarily used as a bronchodilator. Due to its sympathomimetic actions, the World Anti-Doping Agency (WADA) has banned it. Multiple acute weight loss protocols (WLP) are used by Olympic athletes for sports that segregate athletes by weight; these generally involve caloric and water deprivation combined with heat exposure. Athletes use WLP before weigh-in, then transition to different body acute weight regain protocols (WRP) before competitions. Here, we studied the pharmacokinetics of fenoterol under WLP conditions: energetic dietary restriction, decreased water intake, and exposure to a dry sauna (80 ± 2 °C), followed by a WRP. Five elite-level female judo athletes participated in the study. Four received fenoterol (200 μg; n = 2 or 400 μg; n = 2), while one was a control receiving placebo under identical conditions. We measured excretion of the fenoterol parent molecule and presented qualitative data of its sulfated metabolite using QqQ tandem quadrupole mass spectrometry for 118 h. The fenoterol parent appeared earlier in urine than did its conjugated metabolite; excretion profiles were similar among all subjects. The centers of mass for fenoterol parent curves were (time, fenoterol): athlete A (10.9, 7.3); athlete B (9.2, 27.3); athlete C (8.5, 6.9); athlete D (9.7, 5.0). After initiating WRP, we observed a burst in urinary fenoterol excretion once in complete decay. This trend was observed for all four athletes who received fenoterol. Our results suggest that during hypohydration, some of the unmetabolized fenoterol accumulates in tissues, then is released during rehydration. These findings can be important for detecting fenoterol use in athletes.
Competing Interests: Declaration of Competing Interest JA and BA-N are attorneys. LCC is a biochemistry consultant for doping cases.
(Copyright © 2022 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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