Moclobemide upregulated Bcl-2 expression and induced neural stem cell differentiation into serotoninergic neuron via extracellular-regulated kinase pathway.
1. Moclobemide (MB) is an antidepressant drug that selectively and reversibly inhibits monoamine oxidase-A. Recent studies have revealed that antidepressant drugs possess the characters of potent growth-promoting factors for the development of neurogenesis and improve the survival rate of serotonin (5-hydroxytrytamine; 5-HT) neurons. However, whether MB comprises neuroprotection effects or modulates the proliferation of neural stem cells (NSCs) needs to be elucidated. 2. In this study, firstly, we used the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay to demonstrate that 50 microM MB can increase the cell viability of NSCs. The result of real-time reverse transcription-polymerase chain reaction (RT-PCR) showed that the induction of MB can upregulate the gene expressions of Bcl-2 and Bcl-xL. By using caspases 8 and 3, ELISA and terminal dUTP nick-end labeling (TUNEL) assay, our data further confirmed that 50 microM MB-treated NSCs can prevent FasL-induced apoptosis. 3. The morphological findings also supported the evidence that MB can facilitate the dendritic development and increase the neurite expansion of NSCs. Moreover, we found that MB treatment increased the expression of Bcl-2 in NSCs through activating the extracellular-regulated kinase (ERK) phosphorylation. 4. By using the triple-staining immunofluorescent study, the percentages of serotonin- and MAP-2-positive cells in the day 7 culture of MB-treated NSCs were significantly increased (P<0.01). Furthermore, our data supported that MB treatment increased functional production of serotonin in NSCs via the modulation of ERK1/2. In sum, the study results support that MB can upregulate Bcl-2 expression and induce the differentiation of NSCs into serotoninergic neuron via ERK pathway.
Chiou
Shih-Hwa
SH
Department of Medical Research and Education, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan. shchiou@vghtpe.gov.tw
Ku
Hung-Hai
HH
Tsai
Tung-Hu
TH
Lin
Heng-Liang
HL
Chen
Li-Hsin
LH
Chien
Chan-Shiu
CS
Ho
Larry L-T
LL
Lee
Chen-Hsen
CH
Chang
Yuh-Lih
YL
D000818:Animals; D051017:Apoptosis Regulatory Proteins / Q000032:analysis / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D004797:Enzyme-Linked Immunosorbent Assay; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects; D020287:In Situ Nick-End Labeling; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D020912:Moclobemide / Q000494:pharmacology*; D016501:Neurites / Q000187:drug effects; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012701:Serotonin / Q000378:metabolism*; D015398:Signal Transduction; D013234:Stem Cells / Q000187:drug effects*
D051017:Apoptosis Regulatory Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012701:Serotonin; D048049:Extracellular Signal-Regulated MAP Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020912:Moclobemide