Arachidonic acid supplementation enhances hydrogen peroxide induced oxidative injury of neonatal rat cardiac myocytes.
Toraason-M; Wey-H; Woolery-M; Plews-P; Hoffman-P
Cardiovasc Res 1995 May; 29(5):624-628
Rat cardiac myocyte sensitivity to hydrogen-peroxide (7722841) (HP) induced oxidative injury was investigated to determine the effect of variations in phospholipid arachidonic-acid content. Arachidonic- acid supplements of 0, 50, or 100 micromoles (micromol) were administered to cultured cardiac ventricular monocytes from 2 to 4 day old Sprague-Dawley-rats for 36 hours, then the cells were exposed to HP concentrations of 50 or 100microM for 1 hour. Following exposure, cells were subjected to phospholipid fatty acid analysis. Cytotoxicity was determined via lactate-dehydrogenase assay. Thiobarbituric-acid reactive substance assay was performed on cells to assess lipid peroxidation. Arachidonic-acid supplementation produced a 55% increase in the arachidonic-acid content of myocyte phospholipids. Concentration dependent increases in cardiac myocyte lipid peroxidation and cytotoxicity were observed after HP exposure, with enhanced effects seen in cells supplemented with 100microM arachidonic-acid for 36 hours. Marked cytotoxicity and lipid peroxidation was observed in cultured myocytes to which unesterified arachidonic-acid was added. This effect was prevented by addition of 10microM vitamin-E or 1 millimolar desferrioxamine. The authors conclude that cardiac myocyte arachidonic-acid supplementation enhances myocyte susceptibility to HP induced oxidative injury.
NIOSH-Author; Cell-function; Mammalian-cells; In-vitro-studies; Laboratory-animals; Oxidative-processes; Cytotoxic-effects; Fatty-acids; Antioxidants; Peroxides; Cell-cultures;
Author Keywords: cardiomyocyte; arachidonic acid; hydrogen peroxide; oxidative injury; peroxidation; fatty acid composition; antioxidants; aspirin