Nexrutine inhibits cancer cell growth as a consequence of mitochondrial damage and mitophagy

Cell Physiol Biochem. 2015;36(2):763-72. doi: 10.1159/000430136. Epub 2015 May 22.

Abstract

Background/aims: Nexrutine is an herbal extract of Phellodendron amurense and has been used as nutrient supplement in China as well as America. Potential protection effect of Nexrutine has been reported.

Methods: To investigate the mechanism of Nexrutine, we used the HeLa, U2OS and HCT116 as a model. Based on the acidification of cell culture media, we examined the lactate, mitochondria damage as well as mitophagy status by corresponding assay.

Results: Our data suggest that Nexrutine alters the cellular glucose metabolism to promote lactate production. This effect is caused by mitochondrial damage, not an alteration to lactate dehydrogenase activity. As a result of the mitochondrial damage, cell proliferation was inhibited and was associated with an elevation in p21/p27 proteins, which are both important cell cycle inhibitors. As another consequence of the mitochondrial damage, mitophagy was highly activated in Nexrutine-treated cells in a dose-dependent manner. When the autophagy pathway was blocked by siRNAs against BECN1 or ATG7, the growth inhibition caused by Nexrutine was reversed.

Conclusion: Our study revealed that autophagy plays an important role in the inhibition of cancer cell proliferation by Nexrutine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Autophagy / drug effects
  • Cell Line, Tumor
  • Cell Proliferation / drug effects*
  • Glucose / metabolism
  • Humans
  • Male
  • Mitochondria / drug effects*
  • Mitochondria / metabolism
  • Mitochondria / pathology
  • Mitophagy / drug effects*
  • Neoplasms / drug therapy*
  • Neoplasms / metabolism
  • Neoplasms / pathology
  • Plant Extracts / pharmacology*

Substances

  • Antineoplastic Agents, Phytogenic
  • Nexrutine
  • Plant Extracts
  • Glucose