Oxidative damage in keratinocytes exposed to cigarette smoke and aldehydes.
Cigarette smoke (CS) is a significant environmental source of human exposure to chemically active saturated (acetaldehyde) and α,β-unsaturated aldehydes (acrolein) inducing protein carbonylation and dysfunction. The exposure of oral tissues to environmental hazards is immense, especially in smokers. The objectives of the current study were to examine the effect of aldehydes originating from CS on intracellular proteins of oral keratinocytes and to observe the antioxidant response in these cells. Intracellular protein carbonyl modification under CS, acrolein and acetaldehyde exposure in the HaCaT keratinocyte cell line, representing oral keratinocytes was examined by Western blot. Possible intracellular enzymatic dysfunction under the above conditions was examined by lactate dehydrogenase (LDH) activity assay. Oxidative stress response was investigated, by DCF (2,7-dichlorodihydrofluorescein) assay and GSH (glutathione) oxidation. Intracellular protein carbonyls increased 5.2 times after CS exposure and 2.7 times after exposure to 1 μmol of acrolein. DCF assay revealed an increase of fluorescence intensity 3.2 and 3.1 times after CS and acrolein exposure, respectively. CS caused a 72.5% decrease in intracellular GSH levels compared to controls. Activity of intracellular LDH was preserved. α,β-Unsaturated aldehydes from CS are capable of intracellular protein carbonylation and have a role in intracellular oxidative stress elevation in keratinocytes, probably due to the reduction in GSH levels.
Department of Anatomy and Cell Biology, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel; Orthodontic and Craniofacial Department, School of Graduate Dentistry Rambam Health Care Campus, Haifa, Israel.
Katia
K
Avezov
Department of Anatomy and Cell Biology, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel. Electronic address: Reznick@technion.ac.il.
Abraham Z
AZ
Reznick
Department of Anatomy and Cell Biology, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel; Orthodontic and Craniofacial Department, School of Graduate Dentistry Rambam Health Care Campus, Haifa, Israel.
Dror
D
Aizenbud
D000447:Aldehydes / Q000633:toxicity*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D005978:Glutathione; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects*; D018384:Oxidative Stress; D050050:Protein Carbonylation / Q000187:drug effects; D017382:Reactive Oxygen Species; D012906:Smoke / Q000009:adverse effects*; D014026:Nicotiana / Q000633:toxicity*
D000447:Aldehydes; D017382:Reactive Oxygen Species; D012906:Smoke; D005978:Glutathione
Cigarette smoke; Glutathione; Keratinocytes; Oxidative stress; Protein carbonylation; α,β-Unsaturated aldehydes