Helicteres isora Ethanol Extract Induces Apoptotic Cell Death in HepG2 Cells

Background: H. isora is a species of the genus Helicteres, a medicinal plant known to be used in the treatment of liver cancer in Vietnam. However, there has been no recorded about biological activity of H. isora species in Vietnam. The current study aimed to study the antitumor activity through its antioxidant activity and inhibitory properties on hepatocellular carcinoma cells. Methods: Arial parts of Helicteres isora were collected from Dak Nong province. Samples were extracted maceration method in ethanol solvent. The antitumor activity were identified though the DPPH radical scavenging activity (Brand-Williams et al., (1995) and WST-1 assay, Real- time PCR, Hoechst 33258 spectrofluorometric assay and Annexin V-FITC Apoptosis Assay on the human liver cancer cells (HepG2) and non-malignant cells of Chang’s Live. Result: The ethanol extract of H. isora exhibited antioxidant activity with IC50=21.16 µg/ml. H. isora extract also exhibited inhibitory activity on HepG2 cell division with IC50=37 µg/ml after 48 h. The expression of DNA fragmentation of the extract also increased with time (48-72h). Apoptosis induction of extract was associated with up-regulation of pro-apoptotic Bax gene expression and down-regulation of anti-apoptotic Bcl-2 gene expression. The H. isora extract was found to induce the apoptotic process in HepG2 cells through the up and down regulation of the Bax/Bcl-2 gene.