Procyanidin-rich fractions from Parkia biglobosa (Mimosaceae) leaves cause redox-sensitive endothelium-dependent relaxation involving NO and EDHF in porcine coronary artery.
OBJECTIVE
Parkia biglobosa leaves are traditionally used as an antihypertensive agent in Benin. The present study assessed the vasorelaxant activity of different Parkia biglobosa leaf extracts using isolated porcine coronary artery rings.


METHODS
A hydroalcoholic leaf extract was submitted to a multi-step liquid-liquid fractionation with solvents of increasing polarity and the polyphenolic content of the different fractions was analyzed. Vascular reactivity of the different extracts was assessed using porcine coronary artery rings, in the presence or absence of specific pharmacological inhibitors.


RESULTS
The hydroalcoholic, ethyl acetate and butanolic extracts contained mainly procyanidins and monomeric flavonoids. Parkia biglobosa leaf crude extract induced a redox-sensitive endothelium-dependent relaxation mediated by both nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF). The fractionation of the butanolic extract generated 6 fractions, two of which induced stronger vasorelaxation than the original extract and they had a higher phenolic content.


CONCLUSIONS
Parkia biglobosa leaf extract is able to induce endothelium-dependent NO- and EDHF-mediated relaxation in porcine coronary artery rings. The vasorelaxant activity is dependent on their phenolic content and appears to involve mainly procyanidins.
Tokoudagba
Jean-Marie
JM
UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Université de Strasbourg, Faculté de Pharmacie, 67401 Illkirch, France.
Auger
Cyril
C
Bréant
Lise
L
N'Gom
Saliou
S
Chabert
Philippe
P
Idris-Khodja
Noureddine
N
Gbaguidi
Fernand
F
Gbenou
Joachim
J
Moudachirou
Mansourou
M
Lobstein
Annelise
A
Schini-Kerth
Valérie B
VB
D000818:Animals; D001541:Benin; D044946:Biflavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D001685:Biological Factors / Q000378:metabolism*; D002392:Catechin / Q000302:isolation & purification / Q000494:pharmacology*; D003331:Coronary Vessels / Q000187:drug effects* / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D066298:In Vitro Techniques; D009569:Nitric Oxide / Q000378:metabolism*; D010084:Oxidation-Reduction; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry / Q000254:growth & development; D044945:Proanthocyanidins / Q000302:isolation & purification / Q000494:pharmacology*; D013552:Swine; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000302:isolation & purification / Q000494:pharmacology*
D044946:Biflavonoids; D001685:Biological Factors; D010936:Plant Extracts; D044945:Proanthocyanidins; D014665:Vasodilator Agents; C067410:endothelium-dependent hyperpolarization factor; D009569:Nitric Oxide; C017674:procyanidin; D002392:Catechin