Loss of red blood cell glutathione during Mg deficiency: prevention by vitamin E, D-propranolol, and chloroquine.
Mg deficiency results in loss of red blood cell glutathione and was thought to be due to decreased Mg-dependent synthesis. The effects of vitamin E, D-propranolol, and chloroquine on red blood cell glutathione levels in Mg-deficient rats were examined. Feeding the rats a Mg-deficient diet for 3 wk resulted in an approximately 80% decrease in serum Mg and a 55% loss of red blood cell glutathione; concomitantly, plasma thiobarbituric acid reactive (TBAR) materials rose 240%. All three drug treatments had no effect on the plasma Mg levels but significantly inhibited the rise in TBAR content and attenuated (60-80% effective) the loss of glutathione. Red blood cell ghost membranes from the Mg-deficient rats also exhibited 2.3-fold higher TBAR content, which was attenuated by vitamin E treatment. With isolated red blood cells from Mg-sufficient rats, loss of glutathione could be induced by a chemical oxyradical system. Direct protective effects were afforded by alpha-tocopherol and D-propranolol but not by chloroquine. The data suggest that 1) the loss of glutathione during Mg deficiency was due to increased oxidative degradation, 2) both vitamin E and D-propranolol protected by a membrane antiperoxidative action, and 3) chloroquine probably protected by diminishing prooxidant activity secondary to its inhibition of cytokine induction during Mg deficiency.
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Department of Physiology, George Washington University Medical Center, Washington, District of Columbia 20037.
Stafford
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Weglicki
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D000818:Animals; D002738:Chloroquine / Q000494:pharmacology; D004912:Erythrocytes / Q000378:metabolism*; D005978:Glutathione / Q000097:blood*; D008275:Magnesium Deficiency / Q000097:blood*; D008297:Male; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000494:pharmacology; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D013997:Time Factors; D014810:Vitamin E / Q000494:pharmacology
D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D002738:Chloroquine; D011433:Propranolol; D005978:Glutathione