| High
altitude exposure results in decreased oxygen pressure and an increased
formation of reactive oxygen and nitrogen species (RONS), which is
often associated with increases in oxidative damage to lipids, proteins
and DNA. Exposure to high altitude appears to decrease the activity
and effectiveness of antioxidant enzymes system. Moreover, during
high altitude exposure several RONS generating source are activated,
including mitochondrial electron transport chain, xanthine oxidase,
and nitric oxide synthase (NO). Physical exercise at high altitude
can further enhance the oxidative stress. The available information
suggests that RONS are involved and are even a causative factor of
acute mountain sickness. Supplementation of antioxidant seems to be
a necessary step to prevent or decrease to high altitude exposure
associated oxidative stress.
KEY
WORDS: High altitude, reactive oxygen and nitrogen species,
oxidative stress, oxidative damage, antioxidants, acute mountain
sickness.
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