Effect of ovariectomy on inflammation induced by intermittent hypoxia in a mouse model of sleep apnea

Respir Physiol Neurobiol. 2014 Oct 1:202:71-4. doi: 10.1016/j.resp.2014.08.009. Epub 2014 Aug 20.

Abstract

Patient data report marked gender and pre-vs-postmenopausal differences in obstructive sleep apnea (OSA). However, no experimental data are available on how sexual hormones modulate OSA consequences. Here we report novel results on estrogen-modulated heart and brain inflammation in female mice subjected to intermittent hypoxia, a major injurious challenge in OSA. C57BL/6J (14-week old) intact and ovariectomized mice (n=6 each) were subjected to intermittent hypoxia (20 s at 5% and 40s at 21%, 60 cycles/h; 6 h/day). Identical intact and ovariectomized groups breathing room air were controls. After 30 days, the gene expressions of interleukins 6 and 8 (IL-6, IL-8) in the brain and heart tissues were measured. Whereas, compared with normoxia, intermittent hypoxia considerably increased IL-6 and IL-8 gene expressions in intact females, no change was found in ovariectomized mice when comparing normoxia and intermittent hypoxia. These data suggest that estrogens modulate the inflammatory effects of intermittent hypoxia and point to further studies on the role played by sex hormones in OSA.

Keywords: Inflammation; Intermittent hypoxia; Obstructive sleep apnea; Ovariectomy; Sexual hormones.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / metabolism
  • Disease Models, Animal
  • Encephalitis / etiology*
  • Female
  • Gene Expression Regulation / physiology
  • Heart Injuries / etiology
  • Heart Injuries / pathology
  • Hypoxia / complications*
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism
  • Interleukin-8 / genetics
  • Interleukin-8 / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Myocardium / metabolism
  • Organ Size
  • Ovariectomy*
  • RNA, Messenger / metabolism
  • Sleep Apnea Syndromes / pathology
  • Sleep Apnea Syndromes / physiopathology*
  • Time Factors

Substances

  • Interleukin-6
  • Interleukin-8
  • RNA, Messenger