title: Paullinia pinnata extracts rich in polyphenols promote vascular relaxation via endothelium-dependent mechanisms.
abstract: Paullinia pinnata L. (Sapindaceae) is an African tropical plant whose roots and leaves are used in traditional medicine for many purposes, especially for erectile dysfunction, but its action mechanism is unknown. P. pinnata root and leaf methanolic extracts are rich in phenolic compounds. This study shows that both extracts are highly antioxidative and induce a slight transcriptional activity of peroxisome proliferator activated receptor-alpha. They also increased and decreased endothelial nitric oxide synthase and endothelin-1 mRNA levels in bovine aortic endothelial cells, respectively. In this study P. pinnata methanolic extracts in cumulative doses elicited in a dose-dependent manner the relaxation of phenylephrine precontracted isolated rat aortic rings. N-nitro-L-arginine methyl ester significantly attenuated the capacity of both extracts to induce arterial relaxation, indicating that this arterial relaxation was mediated by endothelial nitric oxide release. It could be suggested that the arterial relaxation induced by both extracts could be mainly linked to their capacities to inhibit nitric oxide oxidation through their antioxidant properties.
authors: Laboratoire de Pharmacognosie, Faculté de Pharmacie, Université de Lille 2, Lille, France.
authors: Alexis
authors: A
authors: Zamble
authors: Marie
authors: M
authors: Carpentier
authors: Abdelmejid
authors: A
authors: Kandoussi
authors: Sevser
authors: S
authors: Sahpaz
authors: Olivier
authors: O
authors: Petrault
authors: Tawarak
authors: T
authors: Ouk
authors: Nathalie
authors: N
authors: Hennuyer
authors: Jean-Charles
authors: JC
authors: Fruchart
authors: Bart
authors: B
authors: Staels
authors: Régis
authors: R
authors: Bordet
authors: Patrick
authors: P
authors: Duriez
authors: François
authors: F
authors: Bailleul
authors: Françoise
authors: F
authors: Martin-Nizard