Flavonoids and hepatic cyclic monophosphates in liver injury.

Among the large spectrum of pharmacological activities of flavonoids, play an important role the recently investigated properties involving the arachidonic acid metabolism. In order to clarify the mechanisms of "cytoprotection" of the 3-palmitoyl-(+)-catechin (Palm-cat), a new flavonoid compound (C31 H44 O7) we have studied in experimental hepatitis of the rat, induced by Galactosamine (Ga1N) and E. coli 055:B 5 endotoxin (LPS), hepatic cAMP and cGMP, transaminases, bilirubin and endotoxemia. The Palm-cat significantly increases cyclic-GMP levels in the liver, whereas reduces or slightly modifies the cAMP. Transaminases and bilirubin values increase both in controls and flavonoid treated rats. The flavonoid significantly decreases the frequency of endotoxemia. These effects suggest that RES and hepatocytes functions, immune and inflammatory response can be affected in liver disease by flavonoids via cyclic nucleotides regulation.