J. Pharm. Pharmacogn. Res., vol. 14, no. 1, Article ID 2435, Jan-Feb 2026.
DOI: https://doi.org/10.56499/jppres_14.1.2435Original Article
Bronchodilator, erectogenic, and aphrodisiac effects of thymol, carvacrol, and their acetate derivatives: In vivo, ex vivo, and in silico insights
[Efectos broncodilatadores, erectogénicos y afrodisíacos del timol, carvacrol y sus derivados acetato: conocimientos in vivo, ex vivo e in silico]
Mohammed A. Alamri1, Najeeb Ur Rehman1, Mubarak A. Alamri2, Gamal A. Soliman1, Maged S. Abdel-Kader3*
1Department of Pharmacology and Toxicology, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 16273, Saudi Arabia.
2Department of Pharmaceutical Chemistry, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 16273, Saudi Arabia.
3Department of Pharmacognosy, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 16273, Saudi Arabia.
*E-mail: m.youssef@psau.edu.sa
Abstract
Context: Thymol and carvacrol are components of many essential oils known to exert smooth muscle relaxation.
Aims: To evaluate the relaxant effect of thymol, carvacrol, and their acetate derivatives on isolated tracheal and penile corpus cavernosum smooth muscles of guinea pigs, assess aphrodisiac activity in rats, and explore the potential biological targets via network pharmacology and molecular docking.
Methods: Organ bath experiments were conducted to assess ex vivo relaxant effect, while in vivo aphrodisiac activity was evaluated in rats by monitoring mount latency, mount frequency, intromission latency, intromission frequency, and ejaculation latency. Computational methods were used to predict pharmacokinetic and physicochemical properties, as well as potential gene targets for the compounds. Molecular docking was performed to study interactions with BK potassium channels, which were suspected to mediate the relaxant effects.
Results: Thymol acetate produced the most relaxant effect on bronchial and penial muscles, followed by thymol, carvacrol acetate, and then carvacrol. Iberiotoxin prevented this relaxant effect, confirming the involvement of potassium channels. Administration of thymol and thymol acetate to rats significantly improved all aphrodisiac parameters. Computational analysis revealed a high number of gene targets, including potassium channels. Molecular docking revealed the acetylated variants to bind to a modulatory interface within BK potassium channels. Furthermore, binding was similar to a known allosteric channel activator.
Conclusions: Acetylation of thymol enhanced its bronchodilator, erectogenic, and aphrodisiac activities. Computational analysis suggests interaction with genes encoding potassium channel domains. Molecular docking identified a modulatory pocket within BK potassium channels in which the acetylated analogues bind similarly to a reference ligand.
Keywords: aphrodisiacs; carvacrol; computational analysis; molecular docking simulation; potassium channels; thymol.
Resumen
Contexto: El timol y el carvacrol son componentes de muchos aceites esenciales que se sabe que ejercen una relajación del músculo liso.
Objetivos: Evaluar el efecto relajante del timol, del carvacrol y de sus derivados, el acetato, en los músculos lisos aislados de la tráquea y del cuerpo cavernoso del pene de cobayas, evaluar la actividad afrodisíaca en ratas y explorar los posibles objetivos biológicos mediante farmacología en red y acoplamiento molecular.
Métodos: Se realizaron experimentos de baño de órganos para evaluar el efecto relajante ex vivo, mientras que la actividad afrodisíaca in vivo se evaluó en ratas mediante el seguimiento de la latencia de la montura, la frecuencia de la montura, la latencia de intromisión, la frecuencia de intromisión y la latencia de la eyaculación. Se utilizaron métodos computacionales para predecir propiedades farmacocinéticas y fisicoquímicas, así como posibles objetivos diana para los compuestos. Se realizó un acoplamiento molecular para estudiar las interacciones con los canales de potasio BK, que se sospechaba que mediaban los efectos relajantes.
Resultados: El acetato de timol produjo el mayor efecto relajante sobre los músculos bronquiales y penianos, seguido por el timol, el acetato de carvacrol y luego el carvacrol. La iberiotoxina impidió este efecto relajante, lo que confirma la implicación de los canales de potasio. La administración de timol y de acetato de timol a ratas mejoró significativamente todos los parámetros afrodisíacos. El análisis computacional reveló una gran cantidad de objetivos genéticos, incluyendo canales de potasio. El acoplamiento molecular reveló que las variantes acetiladas se unen a una interfaz moduladora dentro de los canales de potasio BK. Además, la unión fue similar a la de un activador de canal alostérico conocido.
Conclusiones: La acetilación del timol mejoró sus actividades broncodilatadoras, erectogénicas y afrodisíacas. El análisis computacional sugiere una interacción con genes que codifican dominios del canal de potasio. El acoplamiento molecular identificó un bolsillo modulador dentro de los canales de potasio BK en el que los análogos acetilados se unen de manera similar a un ligando de referencia.
Palabras Clave: afrodisíacos; carvacrol; análisis computacional; simulación de acoplamiento molecular; canales de potasio; timol.
Citation Format: Alamri MA, Rehman NU, Alamri MuA, Soliman GA, Abdel-Kader MS (2026) Bronchodilator, erectogenic, and aphrodisiac effects of thymol, carvacrol, and their acetate derivatives: In vivo, ex vivo, and in silico insights. J Pharm Pharmacogn Res 14(1): 2435. https://doi.org/10.56499/jppres_14.1.2435
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