Inhibition of human glioma cell proliferation by altered Bax/Bcl-2-p53 expression and apoptosis induction by Rhaponticum carthamoides extracts from transformed and normal roots

J Pharm Pharmacol. 2016 Nov;68(11):1454-1464. doi: 10.1111/jphp.12619. Epub 2016 Oct 2.

Abstract

Objective: The objective of this study was to determine the cytotoxic effect and apoptotic activity of Rhaponticum carthamoides transformed root (TR) and root of soil-grown plant (NR) extracts in a human glioma primary cells. The effect of these root extracts on cell cycle arrest, mitochondrial membrane potential (ΔΨm) and expression levels of apoptosis-related genes (Bcl-2, Bax and p53) were also examined.

Methods: Cytotoxic activity of root extracts was evaluated by MTT assay. Apoptosis and cell cycle were determined by flow cytometry. Expression levels of apoptosis-related gene were analysed by RT-PCR and Western blotting. ΔΨm was examined by the use of JC-1 reagent.

Key findings: Rhaponticum carthamoides root extracts inhibit cell growth and induce apoptosis in a dose-dependent manner in human glioma cells. The root extracts were found to up-regulate the pro-apoptotic Bax protein and down-regulate the anti-apoptotic Bcl-2 protein, consequently increasing the ratios of Bax/Bcl-2 protein levels. Moreover, an increase of the p53 protein level and reduction of ΔΨm in glioma cells were observed after treatment with NR and TR extracts.

Conclusion: The results of this study may offer a new insight into the potential anticancer activity of R. carthamoides root extracts.

Keywords: Bax; Rhaponticum carthamoides; Bcl-2 and p53 gene expressions; apoptosis; caffeic acid derivatives; glioma primary cells; mitochondrial membrane potential.

Publication types

  • Comparative Study

MeSH terms

  • Agrobacterium / physiology
  • Antineoplastic Agents, Phytogenic / isolation & purification
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apoptosis / drug effects
  • Blotting, Western
  • Brain Neoplasms / drug therapy*
  • Brain Neoplasms / genetics
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / pathology
  • Cell Cycle Checkpoints / drug effects
  • Cell Proliferation / drug effects*
  • Dose-Response Relationship, Drug
  • Glioma / drug therapy*
  • Glioma / genetics
  • Glioma / metabolism
  • Glioma / pathology
  • Leuzea / chemistry*
  • Leuzea / microbiology
  • Membrane Potential, Mitochondrial / drug effects
  • Microscopy, Fluorescence
  • Phytotherapy
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology*
  • Plant Roots / chemistry*
  • Plant Roots / microbiology
  • Plants, Medicinal
  • Proto-Oncogene Proteins c-bcl-2 / genetics
  • Proto-Oncogene Proteins c-bcl-2 / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Signal Transduction / drug effects
  • Transformation, Bacterial
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • bcl-2-Associated X Protein / genetics
  • bcl-2-Associated X Protein / metabolism*

Substances

  • Antineoplastic Agents, Phytogenic
  • BAX protein, human
  • BCL2 protein, human
  • Plant Extracts
  • Proto-Oncogene Proteins c-bcl-2
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • bcl-2-Associated X Protein