Extracts of tamarillo, horned melon, and raspberry, but not extract of pear, inhibit human blood platelet aggregation: Investigating the underlying factors for their differential mechanisms

In addition to their roles in thrombosis, hyperactive platelets contribute to atherosclerosis. Since anti-platelet drugs are not recommended for the vulnerable population with hyperactive platelets to reduce the risk of car-diovascular disease, a search is on to find alternative dietary antiplatelets that can be safely used. We here describe that in a dose-dependent manner, sugar-free extracts of tamarillo, horned melon (kiwano), and rasp-berry inhibited ADP-induced platelet aggregation in platelet-rich plasma, whereas pear extract had no effects. Furthermore, analysis of untargeted metabolites revealed the presence of platelet inhibitory components such as benzoic acid, caffeic acid, and gallic acid in the sugar-free extracts of tamarillo, raspberry, and kiwano but absent in pear extract. All these three fruit extracts inhibited the platelet production of TxB2 and the release of platelet factor 4. Our work suggests that these fruits inhibit platelet aggregation partly due to anti-platelet compounds such as benzoic, caffeic, and gallic acids.