title: Lipid peroxidation in choline-methionine deficiency.
abstract: A deficiency of choline and methionine is hepatocarcinogenic and is associated with an apparent increase in lipid peroxidation. In this study the susceptibility of microsomes and nuclei to ferritin-dependent lipid peroxidation is examined together with the status of the peroxidation-protective systems. Choline-methionine deficiency caused an increase in Se-independent GSH peroxidases (GSH transferase subunit 2) and membrane vitamin E but a decrease in Se-dependent GSH peroxidase and microsomal GSH peroxidase activity. Choline-methionine deficient microsomes and nuclei were 4-fold more susceptible to lipid peroxidation induced in vitro by physiological concentrations of ferritin/ascorbate/ADP; and the peroxidation was less effectively inhibited by GSH and soluble GSH peroxidases than controls. The results indicate that a decreased level of Se-dependent and membrane GSH peroxidases is involved in the increase in lipid peroxidation observed in choline-methionine deficiency.
mesh_terms: D002796:Choline Deficiency / Q000378:metabolism*; D005293:Ferritins / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects*; D008715:Methionine / Q000172:deficiency*; D008862:Microsomes, Liver / Q000378:metabolism; D014810:Vitamin E / Q000378:metabolism
chemical_list: D014810:Vitamin E; D005293:Ferritins; D008715:Methionine; D005979:Glutathione Peroxidase; D005978:Glutathione