Effects of phenolic constituents from the mulberry tree on arachidonate metabolism in rat platelets.

The effects of various phenolic compounds isolated from the rootbark of the mulberry tree on rat platelet cyclooxygenase and lipoxygenase products formed from (1-14C)arachiodonic acid were studied. Kuwanons G and H, sanggenon C, and mulberrofuran Q at concentrations of 10(-3) to 10(-4)M inhibited the formation of 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and thromboxane B2 (cyclooxygenase products); however, they increased the formation of 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) (a lipoxygenase product). Sanggenon D and mulberrofuran J at concentration of 10(-3)M inhibited the formation of HHT, thromboxane B2, and 12-HETE. Mulberrofuran G at a concentration of 10(-3)M inhibited the formation of HHT, thromboxane B2, and 12-HETE, while at 10(-5)M, it inhibited the formation of 12-HETE without affecting the formations of HHT and thromboxane B2. Kuwanon M and mulberroside A did not affect arachidonate metabolism in rat platelets.