Research
In vitro vasorelaxation mechanisms of bioactive compounds extracted from Hibiscus sabdariffa on rat thoracic aorta
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* Corresponding author: Mamadou Sarr mamadousarr@ucad.sn
1 Laboratoire de Physiologie Pharmaceutique, Faculté de Médecine, Pharmacie et Odontologie, Université Cheikh Anta Diop, Dakar, Sénégal
2 Unité Mixte Internationale (UMI 3189 - Environnement, Santé et Sociétés), Université Cheikh Anta Diop, Dakar, Sénégal
3 Laboratoire de Pharmacognosie et Molécules Naturelles Bioactives, Faculté de Pharmacie, Université Louis Pasteur, Strasbourg, France
4 Laboratoire de Chimie Thérapeutique, Faculté de Médecine, Pharmacie et Odontologie, Université Cheikh Anta Diop, Dakar, Sénégal
5 Laboratoire de Botanique, Institut Fondamental d'Afrique Noire, Université Cheikh Anta Diop, Dakar, Sénégal
6 Laboratoire de Physiologie Médicale, Faculté de Médecine, Pharmacie et Odontologie, Université Cheikh Anta Diop, Dakar, Sénégal
7 Biologie Neuro-Vasculaire Intégrée, UMR-CNRS 6214, INSERM 771, Faculté de Médecine, Université d'Angers, Angers, France
Nutrition & Metabolism 2009, 6:45 doi:10.1186/1743-7075-6-45
Published: 2 November 2009Abstract
Background
In this study, we suggested characterizing the vasodilator effects and the phytochemical characteristics of a plant with food usage also used in traditional treatment of arterial high blood pressure in Senegal.
Methods
Vascular effects of crude extract of dried and powdered calyces of Hibiscus sabdariffa were evaluated on isolated thoracic aorta of male Wistar rats on organ chambers. The crude extract was also enriched by liquid-liquid extraction. The various cyclohexane, dichloromethane, ethyl acetate, butanol extracts obtained as well as the residual marc were subjected to Sephadex LH-20 column chromatography. The different methanolic eluate fractions were then analyzed by Thin Layer (TLC) and High Performance Liquid Chromatography (HPLC) and their vascular effects also evaluated.
Results
The H. Sabdariffa crude extract induced mainly endothelium-dependent relaxant effects. The endothelium-dependent relaxations result from NOS activation and those who not dependent to endothelium from activation of smooth muscle potassium channels. The phytochemical analysis revealed the presence of phenolic acids in the ethyl acetate extract and anthocyans in the butanolic extract. The biological efficiency of the various studied extracts, in term of vasorelaxant capacity, showed that: Butanol extract > Crude extract > Residual marc > Ethyl acetate extract. These results suggest that the strong activity of the butanolic extract is essentially due to the presence of anthocyans found in its fractions 43-67.
Conclusion
These results demonstrate the vasodilator potential of hibiscus sabdariffa and contribute to his valuation as therapeutic alternative.