Inhibitory effects of kiwifruit extract on human platelet aggregation and plasma angiotensin-converting enzyme activity.
Previous human studies suggest that supplementation with kiwifruits lowers several cardiovascular risk factors such as platelet hyperactivity, blood pressure and plasma lipids. The cardiovascular health benefit of fruit and vegetables is usually attributed to the complex mixture of phytochemicals therein; however, kiwifruit's cardioprotective factors are not well studied. In this study, we investigated the effects of kiwifruit extract on human blood platelet aggregation and plasma angiotensin-converting enzyme (ACE) activity. A sugar-free, heat-stable aqueous extract with molecular mass less than 1000 Da was prepared from kiwifruits. Typically, 100 g kiwifruits produced 66.3 ± 5.8 mg (1.2 ± 0.1 mg CE) of sugar-free kiwifruit extract (KFE). KFE inhibited both human platelet aggregation and plasma ACE activity in a dose-dependent manner. KFE inhibited platelet aggregation in response to ADP, collagen and arachidonic acid, and inhibitory action was mediated in part by reducing TxA2 synthesis. The IC50 for ADP-induced platelet aggregation was 1.6 ± 0.2 mg/ml (29.0 ± 3.0 μg CE/ml), whereas IC50 for serum ACE was 0.6 ± 0.1 mg/ml (11.0 ± 1.2 μg CE/ml). Consuming 500 mg of KFE (9.0 mg CE) in 10 g margarine inhibited ex vivo platelet aggregation by 12.7%, 2 h after consumption by healthy volunteers (n = 9). All these data indicate that kiwifruit contains very potent antiplatelet and anti-ACE components. Consuming kiwifruits might be beneficial as both preventive and therapeutic regime in cardiovascular disease.
Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo , Oslo , Norway and.
Lili L
LL
Dizdarevic
Dipankar
D
Biswas
M D Main
MD
Uddin
Aud
A
Jørgenesen
Eva
E
Falch
Nasser E
NE
Bastani
Asim K
AK
Duttaroy
D029042:Actinidia / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry*; D006801:Humans; D007703:Peptidyl-Dipeptidase A / Q000737:chemistry*; D010936:Plant Extracts / Q000627:therapeutic use*; D010974:Platelet Aggregation / Q000187:drug effects*; D012307:Risk Factors
D010936:Plant Extracts; D007703:Peptidyl-Dipeptidase A
Angiotensin-converting enzyme (ACE); TxB2; cAMP; kiwifruit; kiwifruit extract; platelet; platelet aggregation; tomato