Evaluation of the effects of the water-soluble total flavonoids from Isodon lophanthoides var.gerardianus (Benth.) H. Hara on apoptosis in HepG2 cell: Investigation of the most relevant mechanisms

J Ethnopharmacol. 2016 Jul 21:188:70-9. doi: 10.1016/j.jep.2016.04.042. Epub 2016 Apr 29.

Abstract

Ethnopharmacological relevance: The water-soluble total flavonoids (WSTF) were extracted from Isodon lophanthoides var. gerardianus (Benth.) H. Hara, a common folk herbal medicine in China, which has been recorded by the "Chinese Pharmacopoeia" in 2015 and used for prevention and clinical treatment of common diseases of liver and gall for many years.

Objective of the study: The aim of this study is to evaluate the effects of WSTF on apoptosis in HepG2 cell and investigate the relevant mechanisms underlying.

Materials and methods: Cytotoxicity was evaluated in HepG2 cells (human hepatoma cell lines) using MTT assay. The influence of the WSTF on the intracellular reactive oxygen species (iROS) and the mitochondrial membrane potential were also determinated. We used flow cytometry analysis to detect the effects of WSTF on apoptosis, cell cycle. Then we applied RT-PCR for genetic expression of main effectors and western blot analysis for activation of main effectors involved in the potential apoptosis signaling pathways.

Results: WSTF inhibited cell growth in HepG2 cells. Moreover, WSTF stimulates to increase amount of iROS, mitochondrial membrane potential, and the apoptotic relevant factors (cytochrome c, caspase-3) in HepG2 cells. WSTF could significantly induce apoptosis through downregulating apoptosis-antagonizing protein (Bcl-2, Survivin, mcl-1) and upregulating apoptosis-promoting proteins (Bax) and cell cycle G0/G1 arrest in HepG2 cells.

Conclusion: The results indicate that WSTF induces cell apoptosis through mitochondrial pathway in the HepG2 cells. Therefore, these studies suggest that WSTF could be used as a chemotherapeutic agent to treat hepatoma.

Keywords: Cell apoptosis; Relevant mechanisms; The water-soluble total flavonoids from Isodon Lophanthoides var. gerardianus (Benth.) H. Hara.

MeSH terms

  • Antineoplastic Agents, Phytogenic / isolation & purification
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apoptosis / drug effects*
  • Apoptosis Regulatory Proteins / genetics
  • Apoptosis Regulatory Proteins / metabolism
  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / genetics
  • Carcinoma, Hepatocellular / metabolism
  • Carcinoma, Hepatocellular / pathology
  • Cell Proliferation / drug effects
  • Dose-Response Relationship, Drug
  • Flavonoids / isolation & purification
  • Flavonoids / pharmacology*
  • G1 Phase Cell Cycle Checkpoints / drug effects
  • Hep G2 Cells
  • Humans
  • Isodon / chemistry*
  • Liver Neoplasms / drug therapy*
  • Liver Neoplasms / genetics
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology
  • Membrane Potential, Mitochondrial / drug effects
  • Mitochondria, Liver / drug effects
  • Mitochondria, Liver / metabolism
  • Mitochondria, Liver / pathology
  • Oxidative Stress / drug effects
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology*
  • Reactive Oxygen Species / metabolism
  • Signal Transduction / drug effects
  • Solubility
  • Solvents / chemistry*
  • Water / chemistry*

Substances

  • Antineoplastic Agents, Phytogenic
  • Apoptosis Regulatory Proteins
  • Flavonoids
  • Plant Extracts
  • Reactive Oxygen Species
  • Solvents
  • Water