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.
Department of Physiology, George Washington University Medical Center, Washington, District of Columbia 20037.
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Mak
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Stafford
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Weglicki
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