Glutathione depletion increases nitric oxide-induced oxidative stress in primary rat hepatocyte cultures: involvement of low-molecular-weight iron.
Various drugs and chemicals can cause a glutathione (GSH) depletion in the liver. Moreover, nitric oxide (NO) can be generated in response to physiological and pathological situations such as inflammation. The aim of this study was to estimate oxidative stress when primary rat hepatocytes were exposed to GSH depletion after NO production. For this purpose, cells were preincubated with lipopolysaccharide (LPS) and gamma-interferon (IFN) for 18 h in order to induce NO production by NO synthase and then L-buthionine sulfoximine (BSO), an inhibitor of GSH synthesis, was added for 5 h. In hepatocyte cultures preincubated with LPS and IFN before BSO addition, an increase in lipid peroxidation was noted. In those cells, an elevation of iron-bound NO and a decrease in free NO led us to suggest the involvement of low-molecular-weight iron (LMW iron) in the enhancement of oxidative stress. Indeed, addition of deferiprone, a chelator of LMW iron, reduced iron-bound NO levels and the extent of oxidative stress. Moreover, an important elevation of LMW iron levels was also observed. As both, N-acetylcysteine, a GSH precursor, and N(G)-monomethyl-L-arginine, a NO synthase inhibitor, totally inhibited the elevation of LMW iron and oxidative stress, a cooperative role could be attributed to NO production and GSH depletion.
Laboratoire de Biologie Cellulaire et Végétale, Pharmaceutiques et Biologiques, Rennes Cedex, France. Sompadthana.Sinbandhit-Tricot@tiscali.fr
Sompadthana
S
Sinbandhit-Tricot
Josiane
J
Cillard
Martine
M
Chevanne
Isabelle
I
Morel
Pierre
P
Cillard
Odile
O
Sergent
D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D019328:Buthionine Sulfoximine / Q000494:pharmacology*; D002478:Cells, Cultured / Q000187:drug effects / Q000378:metabolism; D000077543:Deferiprone; D004050:Ditiocarb / Q000494:pharmacology; D004578:Electron Spin Resonance Spectroscopy; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005978:Glutathione / Q000172:deficiency*; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism; D007371:Interferon-gamma / Q000494:pharmacology; D007501:Iron / Q000378:metabolism*; D007502:Iron Chelating Agents / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D008070:Lipopolysaccharides / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism / Q000494:pharmacology; D018384:Oxidative Stress; D011728:Pyridones / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D019323:omega-N-Methylarginine / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007502:Iron Chelating Agents; D008070:Lipopolysaccharides; D009573:Nitrites; D011728:Pyridones; D019323:omega-N-Methylarginine; D000077543:Deferiprone; D009569:Nitric Oxide; D019328:Buthionine Sulfoximine; D007371:Interferon-gamma; D004050:Ditiocarb; D007501:Iron; D019001:Nitric Oxide Synthase; D005978:Glutathione; D000111:Acetylcysteine