title: Effect of nitric oxide synthase induction on the expression of mitochondrial respiratory chain enzyme subunits in mixed cortical and astroglial cell cultures.
abstract: In the present study we evaluated the effects of NO synthase (NOS) induction on the regulation of cytochrome c oxidase (CO) and F0F1-ATPase subunit expression in astroglial and mixed cortical cell cultures. In mixed cortical cell cultures, 18 h of treatment with lipopolysaccharide (LPS, 0.1 microgram/mL) plus interferon-gamma (INF-gamma, 10 U/mL) caused an increase of mRNAs for CO-I, F0F1-ATPase 6 and also for iNOS at 20 DIV. The induction of both CO-I and F0F1-ATPase 6 was abolished by the NOS inhibitor N-monomethyl-L-arginine (NMMA) or by the enzymatic scavenger superoxide dismutase/catalase (SOD/CAT). In primary astroglial cell cultures, treatment for 18 h with increasing concentrations of LPS and INF gamma, produced an increase in the amount of mitochondrial encoded CO-I and -II subunits, with no significant modifications of nuclear encoded subunit IV. An increase was also observed at level of transcription for CO-I and -II, and F0F1-ATPase 6 mRNAs. These effects were abolished by addition of NMMA or SOD/CAT. mRNA induction of CO-I was higher in mixed cortical than in astroglial cell cultures while that of F0F1-ATPase 6 was similar in both cell types. These results suggest that the expression of mitochondrial encoded subunits (CO-I, CO-II and F0F1-ATPase 6) is up-regulated in response to oxygen and NO reactive species. The activity of cytochrome c oxidase decreased after LPS/INF gamma treatment in both astroglial and mixed cortical cultures. The activity of ATP synthase was unmodified, while ATP content drastically decreased after LPS/INF gamma treatment, in both astroglial and mixed cortical cultures. The enzymatic activities of catalase and Mn-SOD (mitochondrial) showed a significant increase after LPS/INF gamma treatment, which was abolished by NMMA.
authors.affiliation: Institute of Biochemistry, Faculty of Medicine, University of Catania, Italy.
authors.forename: V G
authors.initials: VG
authors.lastname: Nicoletti
authors.forename: A
authors.initials: A
authors.lastname: Caruso
authors.forename: E A
authors.initials: EA
authors.lastname: Tendi
authors.forename: A
authors.initials: A
authors.lastname: Privitera
authors.forename: A
authors.initials: A
authors.lastname: Console
authors.forename: V
authors.initials: V
authors.lastname: Calabrese
authors.forename: F
authors.initials: F
authors.lastname: Spadaro
authors.forename: A
authors.initials: A
authors.lastname: Ravagna
authors.forename: A
authors.initials: A
authors.lastname: Copani
authors.forename: A M
authors.initials: AM
authors.lastname: Stella
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000201:enzymology*; D001921:Brain / Q000201:enzymology*; D002478:Cells, Cultured; D003576:Electron Transport Complex IV / Q000378:metabolism*; D005609:Free Radicals / Q000378:metabolism; D007371:Interferon-gamma / Q000494:pharmacology; D007770:L-Lactate Dehydrogenase / Q000187:drug effects / Q000502:physiology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008928:Mitochondria / Q000201:enzymology*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D051381:Rats
chemical_list: D005609:Free Radicals; D008070:Lipopolysaccharides; D007371:Interferon-gamma; D007770:L-Lactate Dehydrogenase; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D003576:Electron Transport Complex IV; D006180:Proton-Translocating ATPases