Influence of Garcinia hydroxybiflavanonols on RNA synthesis in primary cultured rat hepatocytes and in purified liver cell nuclei

Abstract

Garcinia kola Heckel (Guttiferae) known as “Aki-ilu” (meaning bitter kola) in Igbo language is a large economic tree indigenous to the southern part of Nigeria. The seeds from this tree have been of interest to researchers because of its use in the treatment of various disease conditions in Nigerian traditional medicine. The influence of the Garcinia hydroxybiflavanonols, GB1 and GB2, on the synthesis of RNA in hepatocytes and in purified nuclei from rat livers was studied. A dose-dependent stimulatory effect of the GB1 and GB2 on the rate of synthesis of ribonucleic acids in primary cultured rat hepatocytes was found. In purified nuclei, the synthesis of RNA was not influenced in the presence of these Garcinia hydroxybiflavanonols. A metabolite of the drugs was probably responsible for the observed stimulatory effect on RNA synthesis in the hepatocytes. GB1 is shown to be the main antihepatotoxic principle of G. kola. The possible mechanism of their antihepatotoxic action is discussed. The reported antihepatotoxic activity of the Garcinia hydroxybiflavanonols could be explained, at least in part, by the possible stimulatory effect of the metabolite on the RNA synthetic apparatus. GB1 increased the rate of RNA synthesis about thrice as much as silibinin, a flavanolignan with proven antihepatotoxic activity, and suggests that this compound could be a potential novel antihepatotoxic agent.