title: N-acetyl cysteine protects osteoblastic function from oxidative stress.
abstract: We tested the protective potential of an antioxidant amino acid derivative, N-acetyl cysteine (NAC), in controlling oxidative stress against osteoblasts. Osteoblastic cells extracted from rat bone marrow were cultured. Oxidative stress was induced by adding 100 μM H₂O₂ into the culture media. Then, some H₂O₂-treated cultures were cotreated with 2.5 or 5 mM NAC. Addition of H₂O₂ decreased the number of cells to 50% of untreated cultures at days 2. Addition of 5 mM NAC into H₂O₂ cultures resulted in a dose-dependent increase in the number of cells, with the cell number being 50% greater than that in the 100 μM H₂O₂ culture. The gene expression levels of type I collagen, osteopontin, and osteocalcin were downregulated threefold by H₂O₂ on day 7. The H₂O₂-suppressed gene expression was fully recovered by NAC cotreatment. The mineralizing capability, assessed by Von Kossa staining on day 15, were approximately 1.8 times greater in the NAC + H₂O₂ cotreated group than in the culture with H₂O₂ alone. These NAC-mediated restorations were associated with an NAC dose-dependent increase of intracellular glutathione and a NAC dose-dependent decrease of intracellular reactive oxygen species. In conclusion, oxidative stress induced by H₂O₂ substantially impairs the proliferation, differentiation, and mineralization of osteoblasts. More importantly, the addition of NAC into the culture was found to restore these damages to a near normal level due to the improved redox balance, warranting further in vivo studies to test its therapeutic potential as a local antioxidative stress drug.
authors.affiliation: Laboratory for Bone and Implant Sciences-LBIS, The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, Los Angeles, California, USA. t.ueno.rpro@tmd.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Ueno
authors.forename: M
authors.initials: M
authors.lastname: Yamada
authors.forename: Y
authors.initials: Y
authors.lastname: Igarashi
authors.forename: T
authors.initials: T
authors.lastname: Ogawa
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology*; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002113:Calcification, Physiologic / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D016166:Free Radical Scavengers / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008297:Male; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D015675:Osteocalcin / Q000235:genetics / Q000378:metabolism; D053495:Osteopontin / Q000235:genetics / Q000378:metabolism; D016877:Oxidants / Q000494:pharmacology; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D024042:Collagen Type I; D016166:Free Radical Scavengers; D016877:Oxidants; D017382:Reactive Oxygen Species; C506897:Spp1 protein, rat; D015675:Osteocalcin; D053495:Osteopontin; D006861:Hydrogen Peroxide; D000469:Alkaline Phosphatase; D000111:Acetylcysteine