de-O-methyllasiodiplodin from Ludwigia hyssopifolia causes death of human liver cancer cells through the mitochondrial apoptotic, Akt/NF-κB and STAT3 pathway in vitro

Abstract

(+)-(R)-de-O-methyllasiodiplodin (DOML), isolated from the Chinese herbal medicine Ludwigia hyssop folia, has great potential for development in pharmacological research on hepatocellular carcinoma (HCC). In our study, the CCK-8 assay, morphological observation, flow cytometry (also known as Annexin V-FITC/PI double staining), as well as Western blotting were adopted to study the anti-liver cancer activity and mechanisms of DOML on HepG2 and HuH-7 cells. The research exhibited that DOML dose- and time-dependently reduced the cell viability of HCC cells. DOML treatment resulted in changes in cell morphology, such as irregular edges, reduced volume, and decreased adhesion were observed under the microscope. Flow cytometry analysis indicated that apoptosis is the major form of cell death. In addition, blocking autophagy and necroptosis pathways couldn’t alleviate DOML-induced apoptosis. Protein expression levels of Bax, activated Caspase-3 and Caspase-9, and PARP were increased, while Bcl-2 protein levels were reduced by DOML treatment, which suggested that the mitochondrial apoptotic pathway may be involved in DOML-induced cell death. Moreover, the expression of NF-κB and the phosphorylation of Akt and STAT3 decreased with the increase of dosage, suggesting that the apoptotic mechanism might be related to the Akt/NF-κB and STAT3 signaling pathways. All these results indicate that DOML has the potential effects of anti-hepatoma.