Cultured chick embryo hepatocytes were iron-loaded with ferric nitrilotriacetate. Iron-loading was confirmed by both quantitative cellular iron determinations and ultrastructural studies. With iron-loading, lipid peroxidation, as detected by malonaldehyde released into the medium, occurred at a linear rate for 12h, after which time the rate of malonaldehyde production decreased. No cell toxicity, as detected by lactate dehydrogenase release, was noted. The amount of malonaldehyde recovered in the medium after 18h of exposure to iron represented 24-33% of the total malonaldehyde that could be produced by incubating lysed cells with iron and ascorbate. Cellular glutathione was not affected by iron-stimulated lipid peroxidation, but was increased by allylisopropylacetamide. Although iron-loading by itself had no effect on activity of 5-aminolaevulinate synthase, the first and rate-limiting step in haem synthesis, iron-loading in the presence of the porphyrogenic drug allylisopropylacetamide increased levels of 5-aminolaevulinate synthase 6-fold over levels induced by the drug alone. The antioxidant, butylated hydroxytoluene, totally inhibited iron-stimulated lipid peroxidation, but did not interfere with the effect of iron-loading to potentiate an increase in 5-aminolaevulinate synthase. After 18h of exposure to iron, followed by a change to fresh medium, the iron remaining within the cells did not stimulate further lipid peroxidation over the following 18h, but did potentiate an increase in 5-aminolaevulinate synthase on exposure to allylisopropylacetamide. It therefore appears that lipid peroxidation is not the mechanism by which iron potentiates induction of hepatic 5-aminolaevulinate synthase.
Skip Nav Destination
Follow us on Twitter @Biochem_Journal
Article navigation
May 1983
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkAdvertising
Research Article|
May 15 1983
Iron loading of cultured hepatocytes. Effect of iron on 5-aminolaevulinate synthase is independent of lipid peroxidation Available to Purchase
Publisher: Portland Press Ltd
Online ISSN: 1470-8728
Print ISSN: 0264-6021
© 1983 London: The Biochemical Society
1983
Biochem J (1983) 212 (2): 321–330.
Citation
S I Shedlofsky, H L Bonkowsky, P R Sinclair, J F Sinclair, W J Bement, J S Pomeroy; Iron loading of cultured hepatocytes. Effect of iron on 5-aminolaevulinate synthase is independent of lipid peroxidation. Biochem J 15 May 1983; 212 (2): 321–330. doi: https://doi.org/10.1042/bj2120321
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
Biochemical Society Member Sign in
Sign InSign in via your Institution
Sign in via your InstitutionGet Access To This Article
Cited By
Follow us on Twitter @Biochem_Journal
Open Access for all
We offer compliant routes for all authors from 2025. With library support, there will be no author nor reader charges in 5 journals. Check here |
![]() View past webinars > |