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Title: Paroxetine-induced apoptosis in human osteosarcoma cells: Activation of p38 MAP kinase and caspase-3 pathways without involvement of [Ca{sup 2+}]{sub i} elevation

Abstract

Selective serotonin reuptake inhibitors (SSRIs), a group of antidepressants, are generally used for treatment of various mood and anxiety disorders. There has been much research showing the anti-tumor and cytotoxic activities of some antidepressants; but the detailed mechanisms were unclear. In cultured human osteosarcoma cells (MG63), paroxetine reduced cell viability in a concentration- and time-dependent manner. Paroxetine caused apoptosis as assessed by propidium iodide-stained cells and increased caspase-3 activation. Although immunoblotting data revealed that paroxetine could activate the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH{sub 2}-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK), only SB203580 (a p38 MAPK inhibitor) partially prevented cells from apoptosis. Paroxetine also induced [Ca{sup 2+}]{sub i} increases which involved the mobilization of intracellular Ca{sup 2+} stored in the endoplasmic reticulum and Ca{sup 2+} influx from extracellular medium. However, pretreatment with BAPTA/AM, a Ca{sup 2+} chelator, to prevent paroxetine-induced [Ca{sup 2+}]{sub i} increases did not protect cells from death. The results suggest that in MG63 cells, paroxetine caused Ca{sup 2+}-independent apoptosis via inducing p38 MAPK-associated caspase-3 activation.

Authors:
 [1];  [2];  [3];  [4]
  1. Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, 813, Taiwan (China)
  2. (China)
  3. Department of Biological Sciences, National Sun Yat-sen University, 804, Taiwan (China)
  4. Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, 813, Taiwan (China). E-mail: crjan@isca.vghks.gov.tw
Publication Date:
OSTI Identifier:
20976860
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 218; Journal Issue: 3; Other Information: DOI: 10.1016/j.taap.2006.11.012; PII: S0041-008X(06)00427-3; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ANTIDEPRESSANTS; APOPTOSIS; CALCIUM IONS; DEATH; ENDOPLASMIC RETICULUM; IODIDES; OSTEOSARCOMAS; PHOSPHORYLATION; PROTEINS; SEROTONIN; TIME DEPENDENCE

Citation Formats

Chou, C.-T., Department of Biological Sciences, National Sun Yat-sen University, 804, Taiwan, He Shiping, and Jan, C.-R. Paroxetine-induced apoptosis in human osteosarcoma cells: Activation of p38 MAP kinase and caspase-3 pathways without involvement of [Ca{sup 2+}]{sub i} elevation. United States: N. p., 2007. Web. doi:10.1016/j.taap.2006.11.012.
Chou, C.-T., Department of Biological Sciences, National Sun Yat-sen University, 804, Taiwan, He Shiping, & Jan, C.-R. Paroxetine-induced apoptosis in human osteosarcoma cells: Activation of p38 MAP kinase and caspase-3 pathways without involvement of [Ca{sup 2+}]{sub i} elevation. United States. doi:10.1016/j.taap.2006.11.012.
Chou, C.-T., Department of Biological Sciences, National Sun Yat-sen University, 804, Taiwan, He Shiping, and Jan, C.-R. Thu . "Paroxetine-induced apoptosis in human osteosarcoma cells: Activation of p38 MAP kinase and caspase-3 pathways without involvement of [Ca{sup 2+}]{sub i} elevation". United States. doi:10.1016/j.taap.2006.11.012.
@article{osti_20976860,
title = {Paroxetine-induced apoptosis in human osteosarcoma cells: Activation of p38 MAP kinase and caspase-3 pathways without involvement of [Ca{sup 2+}]{sub i} elevation},
author = {Chou, C.-T. and Department of Biological Sciences, National Sun Yat-sen University, 804, Taiwan and He Shiping and Jan, C.-R.},
abstractNote = {Selective serotonin reuptake inhibitors (SSRIs), a group of antidepressants, are generally used for treatment of various mood and anxiety disorders. There has been much research showing the anti-tumor and cytotoxic activities of some antidepressants; but the detailed mechanisms were unclear. In cultured human osteosarcoma cells (MG63), paroxetine reduced cell viability in a concentration- and time-dependent manner. Paroxetine caused apoptosis as assessed by propidium iodide-stained cells and increased caspase-3 activation. Although immunoblotting data revealed that paroxetine could activate the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH{sub 2}-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK), only SB203580 (a p38 MAPK inhibitor) partially prevented cells from apoptosis. Paroxetine also induced [Ca{sup 2+}]{sub i} increases which involved the mobilization of intracellular Ca{sup 2+} stored in the endoplasmic reticulum and Ca{sup 2+} influx from extracellular medium. However, pretreatment with BAPTA/AM, a Ca{sup 2+} chelator, to prevent paroxetine-induced [Ca{sup 2+}]{sub i} increases did not protect cells from death. The results suggest that in MG63 cells, paroxetine caused Ca{sup 2+}-independent apoptosis via inducing p38 MAPK-associated caspase-3 activation.},
doi = {10.1016/j.taap.2006.11.012},
journal = {Toxicology and Applied Pharmacology},
number = 3,
volume = 218,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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