HIF-1α regulates COXIV subunits, a potential mechanism of self-protective response to microwave induced mitochondrial damages in neurons

Sci Rep. 2018 Jul 10;8(1):10403. doi: 10.1038/s41598-018-28427-5.

Abstract

Anxiety and speculation about potential health hazards of microwaves exposure are spreading in the past decades. Hypoxia-inducible factor-1α (HIF-1α), which can be activated by reactive oxygen species (ROS), played pivotal roles in protective responses against microwave in neuron-like cells. In this study, we established 30 mW/cm2 microwave exposed animal model, which could result in revisable injuries of neuronal mitochondria, including ultrastructure and functions, such as ROS generation and cytochrome c oxidase (COX) activity. We found that the ratio of COXIV-1/COXIV-2, two isoforms of COXIV, decreased at 1 d and increased from 3 d to 14 d. Similar expression changes of HIF-1α suggested that COXIV-1 and COXIV-2 might be regulated by HIF-1α. In neuron-like cells, 30 mW/cm2 microwave down-regulated COX activity from 30 min to 6 h, and then started to recover. And, both HIF-1α transcriptional activity and COXIV-1/COXIV-2 ratio were up-regulated at 6 h and 9 h after exposure. Moreover, HIF-1α inhibition down-regulated COXIV-1 expression, promoted ROS generation, impaired mitochondrial membrane potentials (MMP), as well as abolished microwave induced ATP production. In conclusion, microwave induced mitochondrial ROS production activated HIF-1α and regulated COXIV-1 expression to restore mitochondria functions. Therefore, HIF-1α might be a potential target to impair microwave induced injuries.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Electron Transport Complex IV / chemistry
  • Electron Transport Complex IV / genetics*
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics*
  • Membrane Potential, Mitochondrial / radiation effects
  • Microwaves / adverse effects*
  • Mitochondria / genetics
  • Mitochondria / pathology
  • Mitochondria / radiation effects
  • Neurons / pathology
  • Neurons / radiation effects*
  • Rats
  • Reactive Oxygen Species / chemistry

Substances

  • Hif1a protein, rat
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Reactive Oxygen Species
  • Electron Transport Complex IV