Polyphenol content and modulatory activities of some tropical dietary plant extracts on the oxidant activities of neutrophils and myeloperoxidase.
Young leaves of Manihot esculenta Crantz (Euphorbiaceae), Abelmoschus esculentus (Malvaceae), Hibiscus acetosella (Malvaceae) and Pteridium aquilinum (Dennstaedtiaceae) are currently consumed as green vegetables by peoples in sub-Saharan Africa, Latin America, Asia and their migrants living in Western Europe. Sub-Saharan peoples use Manihot, Abelmoschus and Hibiscus also in the folk medicine to alleviate fever and pain, in the treatment of conjunctivitis, rheumatism, hemorrhoid, abscesses, ... The present study investigates the effects of aqueous extracts of those plants on the production of reactive oxygen species (ROS) and the release of myeloperoxidase (MPO) by equine neutrophils activated with phorbol 12-myristate 13-acetate (PMA). The ROS production was measured by lucigenin-enhanced chemiluminescence (CL), and the release of total MPO by an ELISA method. The study also investigates the effect of the extracts on the activity of MPO by studying its nitration activity on tyrosine and by using a new technique called SIEFED (Specific Immunological Extraction Followed by Enzymatic Detection) that allows studying the direct interaction of compounds with the enzyme. In all experiments, the aqueous extracts of the plants developed concentration-dependent inhibitory effects. A moderate heat treatment did not significantly modify the inhibitory capacity of the extracts in comparison to not heated ones. Total polyphenol and flavonoid contents were determined with an HPLC-UV/DAD analysis and a spectroscopic method using Folin-Ciocalteu reagent. Some polyphenols with well-known antioxidant activities (caffeic acid, chlorogenic acid, hyperoside, rosmarinic acid and rutin) were found in the extracts and may partly explain the inhibitory activities observed. The role of those dietary and medicinal plants in the treatment of ROS-dependent inflammatory diseases could have new considerations for health.
Interfacultary Centre of Drug Research (CIRM), Laboratory of Pharmacognosy, Department of Pharmacy, Faculty of Medicine, Hospital Avenue 1, B36, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.|Centre for Oxygen Research and Development (CORD), Institute of Chemistry B6a, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Cesar N
CN
Tsumbu
Centre for Oxygen Research and Development (CORD), Institute of Chemistry B6a, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Ginette
G
Deby-Dupont
Interfacultary Centre of Drug Research (CIRM), Laboratory of Pharmacognosy, Department of Pharmacy, Faculty of Medicine, Hospital Avenue 1, B36, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Monique
M
Tits
Interfacultary Centre of Drug Research (CIRM), Laboratory of Pharmacognosy, Department of Pharmacy, Faculty of Medicine, Hospital Avenue 1, B36, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Luc
L
Angenot
Interfacultary Centre of Drug Research (CIRM), Laboratory of Pharmacognosy, Department of Pharmacy, Faculty of Medicine, Hospital Avenue 1, B36, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Michel
M
Frederich
Centre for Oxygen Research and Development (CORD), Institute of Chemistry B6a, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Stephane
S
Kohnen
Centre for Oxygen Research and Development (CORD), Institute of Chemistry B6a, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Ange
A
Mouithys-Mickalad
Centre for Oxygen Research and Development (CORD), Institute of Chemistry B6a, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.|Department of Clinical Sciences, Large Animal Surgery, Faculty of Veterinary Medicine, B41, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Didier
D
Serteyn
Centre for Oxygen Research and Development (CORD), Institute of Chemistry B6a, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.|Department of Clinical Sciences, Large Animal Surgery, Faculty of Veterinary Medicine, B41, University of Liège, Sart Tilman, 4000 Liège 1, Belgium.
Thierry
T
Franck
D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D032497:Dennstaedtiaceae / Q000737:chemistry* / Q000378:metabolism; D019665:Euphorbiaceae / Q000737:chemistry* / Q000378:metabolism; D005419:Flavonoids / Q000032:analysis / Q000737:chemistry; D006736:Horses; D019660:Malvaceae / Q000737:chemistry* / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D009195:Peroxidase / Q000378:metabolism*; D010936:Plant Extracts / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism; D010946:Plants, Medicinal / Q000737:chemistry / Q000378:metabolism; D059808:Polyphenols / Q000032:analysis / Q000737:chemistry* / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D005419:Flavonoids; D010936:Plant Extracts; D059808:Polyphenols; D017382:Reactive Oxygen Species; D009195:Peroxidase; D013755:Tetradecanoylphorbol Acetate