Pharmacokinetics and Ex Vivo Activity of 7-Methylxanthine, an Inhibitor of Monosodium Urate Crystallization

Background/Objectives: 7-Methylxanthine (7-MX) is a naturally occurring metabolite of caffeine and theobromine that can inhibit the crystallization of monosodium urate (MSU) and may be useful for the prevention or treatment of gout. However, the pharmacokinetics and ex vivo activity of 7-MX remain p...

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Detalles Bibliográficos
Autores: Ferrer, Miguel D., Dietrich, Jaume, Isern Amengual, Bernat, Pérez-Ferrer, Maria Del Mar, Albertí, Joan, Grases, Fèlix, Costa-Bauzà, Antonia
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Conselleria de Salut i Consum del Govern de les Illes Balears
Repositorio:Docusalut
Idioma:inglés
OAI Identifier:oai:docusalut.com:20.500.13003/25259
Acceso en línea:https://hdl.handle.net/20.500.13003/25259
Access Level:acceso abierto
Palabra clave:7-methylxanthine
gout
monosodium urate
oral administration
pharmacokinetics
Descripción
Sumario:Background/Objectives: 7-Methylxanthine (7-MX) is a naturally occurring metabolite of caffeine and theobromine that can inhibit the crystallization of monosodium urate (MSU) and may be useful for the prevention or treatment of gout. However, the pharmacokinetics and ex vivo activity of 7-MX remain poorly characterized. Methods: The present study assessed the pharmacokinetics of 7-MX in Sprague Dawley rats following a single oral dose (30 mg/kg), and the ex vivo inhibition of MSU crystallization by 7-MX in rat plasma after the repeated administration of oral 7-MX. Results: The pharmacokinetic analysis showed that 7-MX reached peak plasma concentration (Cmax ≈ 30 µM) at 30 min after administration (tmax), the terminal half-life was approximately 1.4 h, and there was no evidence of accumulation after repeated daily dosing. After repeated administration, the relationship between dose (30 or 60 mg/kg) and plasma concentration was proportional. In vitro and ex vivo crystallization assays demonstrated that 7-MX inhibited MSU crystallization in a concentration-dependent manner. The in vitro studies showed that 100 µM 7-MX inhibited up to 74% of MSU crystallization under supersaturated conditions (400 mg/L urate). The ex vivo experiments indicated that plasma from rats that received 30 or 60 mg/kg of 7-MX had 41.4% and 52.6% inhibition of crystallization, consistent with the measured plasma concentrations. Conclusions: These findings confirm that oral administration of 7-MX to rats led to a plasma level that was sufficient to decrease MSU crystallization in plasma, and there were no observable toxicities. These results support the potential of 7-MX as a safe oral treatment for gout, especially in combination with urate-lowering therapies, such as allopurinol. Further clinical investigations are warranted to confirm the therapeutic potential of 7-MX in humans.