Selegiline increases heme oxygenase-1 expression and the cytotoxicity produced by dopamine treatment of neuroblastoma SK-N-SH cells

• Published in: Brazilian journal of medical and biological research Vol. 37; no. 7; pp. 1055 - 1062
• Main Authors: Rieder, C R M, Williams, A C, Ramsden, D B
• Format: Journal Article
• Language: English
• Published: Brazil Associação Brasileira de Divulgação Científica 01-07-2004
• Subjects: BIOLOGY; Blotting, Northern; Cardiotonic Agents - pharmacology; Dopamine; Dopamine - pharmacology; Gene Expression Regulation, Enzymologic - drug effects; Heme Oxygenase (Decyclizing) - drug effects; Heme Oxygenase (Decyclizing) - metabolism; Heme Oxygenase-1; Humans; MEDICINE, RESEARCH & EXPERIMENTAL; Membrane Proteins; Neuroblastoma - pathology; Neuroprotective Agents - pharmacology; Oxidative stress; Oxidative Stress - drug effects; Parkinson's disease; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - analysis; Selegiline; Selegiline - pharmacology; Tumor Cells, Cultured; Selegiline; Oxidative stress; Parkinson's disease; Dopamine
• ISSN: 0100-879X; 1414-431X; 0100-879X; 1414-431X
• DOI: 10.1590/S0100-879X2004000700015

Increased dopamine catabolism may be associated with oxidative stress and neuronal cell death in Parkinson's disease. The present study was carried out to examine the effect of dopamine on the expression of heme oxygenase-1 and -2 (HO-1 and HO-2) in human neuroblastomas (SK-N-SH cell line) and the effects of selegiline and antioxidants on this expression. Cells were kept with close control of pH and were incubated with varying concentrations of dopamine (0.1-100 microM) for 24 h. HO-1 and HO-2 cDNA probes were prepared by reverse transcription-polymerase chain reaction amplification. The mRNA expression of HO-1 and HO-2 was measured by Northern blot analysis. The levels of HO-1 mRNA increased after dopamine treatment, in a dose-dependent manner, in all cell lines studied, whereas levels of the two HO-2 transcripts did not. The HO-1 and HO-2 protein expression was analyzed by Western blotting. HO-1 protein was undetectable in untreated SK-N-SH cells and increased after treatment with dopamine. In contrast, the HO-2 protein (36 kDa) was detected in untreated cells and the levels did not change as a result of treatment. Alpha-tocopherol (10-100 microM) and ascorbic acid (100 microM) did not attenuate the effects of dopamine. Selegiline (10 microM) produced significant increase (P < 0.01) in the induction of HO-1 by dopamine (more than six times the control values). The increased expression of HO-1 following dopamine treatment indicates that dopamine produces oxidative stress in this cell line.