Effect of pre-breathing oxygen at different depth on oxidative status and calcium concentration in lymphocytes of scuba divers

Acta Physiol (Oxf). 2011 May;202(1):69-78. doi: 10.1111/j.1748-1716.2010.02247.x. Epub 2011 Mar 1.

Abstract

Aim: In-water pre-breathing oxygen at various depths reduces decompression-induced bubble formation and platelet activation, but it could induce side effects such as oxidative stress. The aim of this study was to investigate the effect of in-water pre-breathing oxygen, at different depths, on the oxidative status and intracellular calcium ([Ca(2+) ]i) of peripheral blood lymphocytes isolated from six divers. They participated in a 4-diving protocol. Two week recovery time was allowed between successive dives. Before diving, all divers, for 20 min, breathed normally at sea level (dive 1), 100% oxygen at sea level (dive 2), 100% oxygen at 6 msw (dive 3), 100% oxygen at 12 msw (dive 4). Then they dived to 30 msw for 20 min with air tank.

Methods: Blood samples were collected before and after each dive. Hydrogen peroxide (H(2) O(2) ) levels, catalase (CAT) activity, mRNA expression of CAT, glutathione peroxidase (GPx) and superoxide dismutase (SOD), and the [Ca(2+) ]i in lymphocytes were measured.

Results: The dives slightly decreased lymphocyte number and significantly reduced lymphocyte H(2) O(2) levels. CAT activity was higher after scuba diving and, dive 3 enhanced mRNA gene expression of CAT, GPx and SOD. The [Ca(2+) ]i was higher after dive 1 and 2 than pre-diving, while was maintained at pre-diving value after dive 3 and 4.

Conclusion: Our results suggest that pre-breathing oxygen, in particular at 12 msw, may enhance lymphocyte antioxidant activity and reduce reactive oxygen species levels. Pre-breathing oxygen in water may also preserve calcium homeostasis, suggesting a protective role in the physiological lymphocyte cell functions.

MeSH terms

  • Adult
  • Calcium / metabolism*
  • Catalase / metabolism
  • Decompression Sickness / prevention & control
  • Diving / physiology*
  • Humans
  • Hydrogen Peroxide / blood
  • Hyperbaric Oxygenation* / adverse effects
  • Hyperbaric Oxygenation* / methods
  • Lymphocytes / metabolism*
  • Lymphocytes / physiology
  • Male
  • Middle Aged
  • Oxidants / blood
  • Oxidative Stress*
  • Oxygen / metabolism*
  • Oxygen Consumption / physiology
  • Oxygen Inhalation Therapy
  • RNA, Messenger / metabolism
  • Young Adult

Substances

  • Oxidants
  • RNA, Messenger
  • Hydrogen Peroxide
  • Catalase
  • Oxygen
  • Calcium