Quercetin and kaempferol derivatives isolated from aerial parts of Lens culinaris Medik as modulators of blood platelet functions

Abstract

Quercetin and kaempferol show cardioprotective potential. Our preliminary results have demonstrated that the crude extract, phenolic fraction and different flavonoids (including quercetin and kaempferol derivatives) isolated from aerial parts of lentil (Lens culinaris Medik.) have anticoagulant properties and antioxidant activity in human plasma. The objective was to investigate anti-platelet properties of four quercetin derivatives (compound 1 (quercetin 3-O-β-d-glucopyranosyl-(1→2)-β-d-galactopyranoside-7-O-β-d-glucuropyranoside); compound 2 (quercetin 3-O-[(6-O-E-caffeoyl)-β-d-glucopyranosyl-(1→2)]-β-d-galactopyranoside-7-O-β-d-glucuropyranoside); compound 3 (quercetin 3-O-[(6-O-E-p-coumaroyl)-β-d-glucopyranosyl-(1→2)]-β-d-galactopyranoside-7-O-β-d-glucuropyranoside); compound 4 (quercetin 3-O-[(6-O-E-feruloyl)-β-d-glucopyranosyl-(1→2)]-β-d-galactopyranoside-7-O-β-d-glucuropyranoside)), and 3 derivatives of kaempferol (compound 5 (kaempferol 3-O-[(6-O-E-feruloyl)-β-d-glucopyranosyl-(1→2)]-β-d-galactopyranoside-7-O-β-d-glucuropyranoside); compound 6 (kaempferol 3-O-{[(6-O-E-p-coumaroyl)-β-d-glucopyranosyl(1→2)]-α-l-rhamnopyranosyl-(1→6)}-β-d-galactopyranoside-7-O-α-l-rhamnopyranoside); compound 7 (kaempferol 3-O-[(6-O-E-caffeoyl)-β-d-glucopyranosyl-(1→2)]-β-d-galactopyranoside-7-O-(2-O-E-caffeoyl')-β-d-glucuropyranoside)) isolated from Lens culinaris Medik. The aim of our research (in vitro) was also to investigate anti-platelet activity of the crude extract and phenolic fraction obtained from lentil aerial parts. Anti-platelet potential was measured with the use of different parameters. Our research showed that in vitro anti-platelet actions of quercetin and kaempferol derivatives, especially two compounds (compound 4 and 7), were higher than those of other investigated flavonoids - the crude extract and phenolic fraction isolated from aerial parts of lentil. This may represent a novel avenue of investigation for the development of new anti-platelet strategies and management of current therapies in cardiovascular diseases associated with hyperactivation of platelets.