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Function of intramitochondrial melatonin and its association with Warburg metabolism

  • 0Department of Cell Systems and Anatomy, UT Health San Antonio, Long School of Medicine, San Antonio, TX, USA..
Cellular Signalling +

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March 23, 2025

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March 23, 2025

View abstract on PubMed

Summary

This summary is machine-generated.

Melatonin supplementation can reverse Warburg metabolism in cancer cells by reducing mitochondrial reactive oxygen species (ROS) and restoring pyruvate metabolism. This intervention inhibits cancer cell proliferation and tumor growth.

Area Of Science

  • Biochemistry
  • Oncology
  • Mitochondrial Metabolism

Background

  • Warburg metabolism, or aerobic glycolysis, is a hallmark of cancer, characterized by high mitochondrial reactive oxygen species (ROS) generation.
  • Cancer cells exhibit reduced intramitochondrial melatonin due to inhibited pyruvate dehydrogenase complex (PDH), leading to increased ROS and aerobic glycolysis.
  • Elevated ROS may upregulate the hypoxia-inducible factor 1α (HIF-1α)/pyruvate dehydrogenase kinase (PDK) axis, further inhibiting PDH and promoting cancer growth.

Purpose Of The Study

  • To investigate the role of melatonin in reversing Warburg metabolism in cancer cells.
  • To explore the potential of melatonin supplementation as a therapeutic strategy against cancer.

Main Methods

  • The study hypothesizes that depressed melatonin levels initiate aerobic glycolysis and that elevated ROS upregulate the HIF-1α/PDK axis, inhibiting PDH.
  • The research speculates on the mechanism by which melatonin supplementation could counteract these effects.

Main Results

  • Exposing Warburg-metabolizing cancer cells to melatonin increases intramitochondrial melatonin levels.
  • This elevation reduces mitochondrial ROS (mtROS), interrupts aerobic glycolysis, and inhibits tumor cell proliferation.
  • Mechanistically, melatonin upregulates the sirtuin 3 (SIRT3)/FOXO/PDH axis, promoting pyruvate entry into mitochondria and enhancing intrinsic melatonin production.
  • Melatonin also inhibits HIF-1α, decreasing PDK activity and disinhibiting PDH, thereby reversing Warburg metabolism.

Conclusions

  • Melatonin supplementation can reverse Warburg metabolism by restoring mitochondrial function and redox homeostasis.
  • This reversal involves the upregulation of the SIRT3/FOXO/PDH axis and the inhibition of the HIF-1α/PDK axis.
  • Melatonin shows promise as a therapeutic agent for inhibiting cancer cell proliferation and tumor growth by targeting core metabolic pathways.

Keywords:

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