Antihypertensive and cognitive effects of grape polyphenols in estrogen-depleted, female, spontaneously hypertensive rats.
Both endogenous and dietary estrogens reduce hypertension and enhance cognitive abilities in estrogen-depleted female spontaneously hypertensive rats (SHR). Many of the beneficial effects of estrogens/phytoestrogens also appear to be provided by other polyphenols (e.g., proanthocyanidins) in grape seed, which lack appreciable estrogenic receptor binding. The present study tested the hypothesis that similar to phytoestrogens, proanthrocyanidins in grape seed polyphenols reduce salt-sensitive hypertension in young, estrogen-depleted SHR. SHR were ovariectomized at 4 wk of age and placed on phytoestrogen-free diets with or without 0.5% grape seed extract added and with high (8.0%) or basal (0.6%) NaCl. After 10 wk on the diets, grape proanthrocyanidin supplementation significantly reduced arterial pressure in the rats fed the basal (10 mmHg) and high (26 mmHg)-NaCl diet, compared with the nonsupplemented controls. In vitro superoxide production was significantly reduced (23%) by the grape seed polyphenols. Spatial learning (8-arm-radial maze) in the SHR on the basal NaCl diets was improved by dietary grape seed polyphenols. These results indicate that grape seed polyphenols decrease arterial pressure in SHR, probably via an antioxidant mechanism.
Peng
Ning
N
Dept. of Cell Biology, University of Alabama at Birmingham, 1900 Univ. Blvd./THT 950, Birmingham, AL 35294-0006, USA. jmwyss@uab.edu
Clark
John T
JT
Prasain
Jeevan
J
Kim
Helen
H
White
C Roger
CR
Wyss
J Michael
JM
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D003071:Cognition / Q000187:drug effects*; D004967:Estrogens / Q000172:deficiency*; D005260:Female; D005419:Flavonoids / Q000494:pharmacology*; D006973:Hypertension / Q000235:genetics / Q000503:physiopathology* / Q000523:psychology*; D018782:Maze Learning / Q000187:drug effects; D010636:Phenols / Q000494:pharmacology*; D059808:Polyphenols; D051381:Rats; D011918:Rats, Inbred SHR; D013481:Superoxides / Q000378:metabolism; D027843:Vitis / Q000737:chemistry*
D000959:Antihypertensive Agents; D004967:Estrogens; D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D013481:Superoxides