Antihypertensive and antioxidant effects of Allanblackia floribunda Oliv. (Clusiaceae) aqueous extract in alcohol- and sucrose-induced hypertensive rats.
OBJECTIVE
Allanblackia floribunda Oliv. (Clusiaceae), an evergreen tree of the rain-forest has long been used in traditional African medicine to treat hypertension. The aim of this study was to evaluate the protective effect of Allanblackia floribunda aqueous extract on alcohol- and sugar-induced hypertension in rats.


METHODS
Alcohol-induced hypertensive rats (AHR) were obtained by oral administration of ethanol (3g/kg/day) while sucrose (5, 6 and 7% in drinking water) was used for sucrose-induced hypertensive rat (SuHR). Both models of animals concomitantly received either aqueous extract (200 or 400mg/kg; p.o.) or nifedipine (10mg/kg; p.o.) all along the 8 weeks of experiment. Blood pressure and heart rate were measured using the direct cannulation method. The effects of the plant extract on lipid profile, oxidative stress markers, as well as on kidney and liver functions were evaluated at the end of the treatment by the colorimetric method.


RESULTS
At the doses of Allanblackia floribunda (200 and 400mg/kg/day) significantly prevented (21.74; 26.65% and 11.71; 24.58% of reduction) the increase in mean blood pressure on AHR and SuHR, respectively. Administration of the plant extract at the dose of 400mg/kg led to the prevention of total cholesterol (42.82%), HDL-cholesterol (36.59%) and triglycerides (9.67%) increase in serum lipid in AHR as compared to the untreated AHR. In SuHR, the extract significantly prevented the high concentrations of total cholesterol (44.08%) and triglycerides (33.05%) induced by sucrose treatment as compared to the untreated SuHR, without affecting that of HDL-cholesterol. Allanblackia floribunda (200 and 400mg/kg) also prevented the increase in atherogenic index by 54.45 and 42.94% in AHR and by 23.70 and 44.32% in SuHR, respectively. Allanblackia floribunda (400mg/kg) prevented the increase in bilirubine (19.59 and 16.56%), urea (33.36 and 28.2%), ALT (29.55 and 33.09%) and AST (36.28 and 37.12%) of AHR and SuHR, respectively. Treatment with plant extract significantly prevented the increase of superoxide dismutase (SOD), malondialdehyde (MDA) and catalase and the decrease of reduced glutathione (GSH) concentration in aorta, heart, kidney and liver of AHR and SuHR.


CONCLUSIONS
These results demonstrate that the aqueous extract of Allanblackia floribunda can prevent alcohol- and sugar-induced hypertension and oxidative stress in rats. These findings could therefore justify its use in traditional medicine.
Bilanda
Danielle Claude
DC
Department of Animal Biology and Physiology, Laboratory of Animal Physiology, University of Yaounde I, P.O. Box 812 Yaounde, Cameroon.
Dimo
Théophile
T
Dzeufiet Djomeni
Paul Désiré
PD
Bella
Ndzana Martin Thierry
NM
Aboubakar
Oumarou Bibi Farouck
OB
Nguelefack
Télesphore Benoit
TB
Tan
Paul V
PV
Kamtchouing
Pierre
P
D000284:Administration, Oral; D000818:Animals; D000959:Antihypertensive Agents / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use*; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use; D015415:Biomarkers / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects; D002374:Catalase / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D008076:Cholesterol, HDL / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism; D028084:Clusiaceae; D000431:Ethanol / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D006973:Hypertension / Q000188:drug therapy*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008055:Lipids / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010936:Plant Extracts / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013395:Sucrose / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000378:metabolism; D014280:Triglycerides / Q000378:metabolism; D014867:Water / Q000494:pharmacology
D000959:Antihypertensive Agents; D000975:Antioxidants; D015415:Biomarkers; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D008055:Lipids; D010936:Plant Extracts; D014280:Triglycerides; D014867:Water; D000431:Ethanol; D008315:Malondialdehyde; D013395:Sucrose; D002784:Cholesterol; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione