Vasorelaxant effect of phenylpropanoids: Methyl eugenol and eugenol in human umbilical cord vein

• Published in: Biomedicine & pharmacotherapy Vol. 178; p. 117227
• Main Authors: de Alencar Silva, Andressa, de Morais, Luís Pereira, de Sena Bastos, Carla Mikevely, de Menezes Dantas, Debora, Batista, Paulo Ricardo, Dias, Francisco Junio, Alencar de Menezes, Irwin Rose, Cardoso, José Henrique Leal, Raposo, António, Han, Heesup, Coutinho, Henrique Douglas Melo, Barbosa, Roseli
• Format: Journal Article
• Language: English
• Published: France Elsevier Masson SAS 01-09-2024; Elsevier
• Subjects: Human umbilical cord; Natural molecules; Vasorelaxant; Vasorelaxant; Natural molecules; Human umbilical cord
• ISSN: 0753-3322; 1950-6007; 1950-6007
• DOI: 10.1016/j.biopha.2024.117227

Methyl-eugenol (ME) and eugenol (EUG) are phenylpropanoids with vasodilatory effects. While EUG's vasorelaxant effect in human umbilical artery (HUA) is known, their action in veins is unclear. This study aimed to evaluate ME and EUG in human umbilical vein (HUV). Isolated HUV underwent tension recordings. ME and EUG caused 100 % relaxation in HUV, with EC50 values corresponding to: 174.3 ± 7.3 and 217.3 ± 6.2 µM for ME and EUG respectively in presence of K+; 362.3 ± 5.4 and 227.7 ± 4.9 µM for ME and EUG respectively and in presence of serotonin (5-HT). It was observed that in presence of BaCl2 and CaCl2 evoked contractions, ME (800 and 1000 µM) and EUG (1000 and 1400 µM) prevent the contractions. In presence of K+ channel blockers it was observed that ME promoted relaxation compared to its control, except in presence of 4-AP, suggesting a possible Ca2+-dependent K+ channel activation for this molecule; EUG increased all EC50 in presence of the K+ blockers except in presence of TEA 1 mM. Greater pharmacological potency was observed for ME. This study highlights natural substances' effects on HUV contractile parameters, suggesting ME and EUG as potential vasodilators in maintaining fetal oxygenation and venous flow during gestational hypertensive syndromes.
•This is the first report of the vasodilator effect of Eugenol and Methyl-eugenol in HUV.•Eugenol and Methyl-eugenol caused relaxation against different evoked contraction pathways.•These effects have a possible involvement with K+ channels and L-type Ca2+ channels.