becoming a better Clinician
Oxygen Toxicity / Free Radical
last updated: January 19, 2017
Orlando Debesa
Give me your tired, your poor,
your huddled masses yearning to breathe free,
The wretched refuse of your seeming shore.
Send these, the homeless, temptest-toss, to me.
--Emma Lazarus
Oxygen is Good
Essential for aerobic respiration
Generation of usable energy from food
Metabolism of endogenous intermediates
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steroid hormones
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prostaglandins
Endoplasmic Reticulum (ER)
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most oxidized organelle in the cell
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the formation of disulfide bonds for protein folding is guided by the oxidizing nature of the ER
Immune defense functions/cell killing / Inflammation
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thru the formation of HOCl- by the phagocytes
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NADPH oxidase generates superoxide
Generation of NO*
Metabolism of drugs/xenobiotics
Oxygen is bad
Hydroxyl ion (OH-)
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DNA/protein damage
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lipid peroxidation
H2O2
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glutathione / catalase
Antioxidants
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glutathione