Effect of Fe2+ -induced lipid peroxidation upon microsomal steroidogenic enzyme activities of porcine adrenal cortex.
When porcine adrenocortical microsomes were treated with Fe2+, enhanced production of malondialdehyde was observed as a result of membrane lipid peroxidation. By treatment of the microsomes with Fe2+, the activity of delta 5-3 beta-hydroxysteroid dehydrogenase coupled with delta 5-delta 4 isomerase, concentration of cytochrome P-450 and the activity of the cytochrome-involving enzyme systems such as 17 alpha- and 21-hydroxylases were significantly reduced. 17 alpha-Hydroxylase activity was more effectively decreased by Fe2+ than that of 21-hydroxylase. On the other hand, activity of NADH- and NADPH-cytochrome c reductases remained unchanged or somewhat increased. Both the induction of lipid peroxidation and the decrease of the enzyme activities were prevented by alpha-tocopherol and N,N' -diphenyl-rho-phenylenediamine.
D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D000302:Adrenal Cortex / Q000648:ultrastructure*; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005296:Ferrous Compounds / Q000494:pharmacology*; D007501:Iron / Q000494:pharmacology*; D008054:Lipid Peroxides / Q000378:metabolism*; D008315:Malondialdehyde / Q000378:metabolism; D008861:Microsomes / Q000187:drug effects / Q000201:enzymology*; D013254:Steroid 17-alpha-Hydroxylase / Q000378:metabolism; D013255:Steroid 21-Hydroxylase / Q000378:metabolism; D013552:Swine; D014810:Vitamin E / Q000494:pharmacology
D005296:Ferrous Compounds; D008054:Lipid Peroxides; D014810:Vitamin E; D008315:Malondialdehyde; D003577:Cytochrome P-450 Enzyme System; D007501:Iron; D015096:3-Hydroxysteroid Dehydrogenases; D013255:Steroid 21-Hydroxylase; D013254:Steroid 17-alpha-Hydroxylase