title: Nonylphenol and octylphenol-induced apoptosis in human embryonic stem cells is related to Fas-Fas ligand pathway.
abstract: Human embryonic stem (hES) cells have been proposed as a source of various cell types for cell replacement therapy. Besides their potential in therapeutic uses, ES cells also have other potential applications, such as in drug discovery and in vitro screening assays of various toxicants. Nonylphenol (NP) and octylphenol (OP) are common environmental contaminants, known to disrupt the reproductive and endocrine system. However, little is known about their toxicological effects on early embryonic development in humans. In this study, we used undifferentiated hES cells and the neural progenitor cells derived from them to investigate the potential toxicity of NP and OP. Our results show that the cytotoxic effects of NP and OP involve DNA fragmentation, the major characteristic of apoptosis. The NP- and OP-induced apoptosis was concomitant with the increased activity of Caspase-8 and -3. Moreover, both Fas and Fas ligand (FasL) protein expressions were markedly increased in the NP- or OP-exposed hES cells. These results suggest that NP and OP are able to trigger apoptosis in hES cells via a pathway dependent on caspase activation and Fas-FasL interaction. In particular, hES cell-derived neural progenitor cells had a higher sensitivity to the toxicants than undifferentiated hES cells, thereby suggesting that the toxic stress response may differ depending on the developmental stage. These findings offer new perspectives for understanding the fundamental mechanisms in chemical-induced apoptosis in hES cells.
authors.affiliation: Laboratory of Stem Cell Biology, Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea.
authors.forename: Suel-Kee
authors.initials: SK
authors.lastname: Kim
authors.forename: Byung-Kak
authors.initials: BK
authors.lastname: Kim
authors.forename: Joong-Hyun
authors.initials: JH
authors.lastname: Shim
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Gil
authors.forename: Yong-Dal
authors.initials: YD
authors.lastname: Yoon
authors.forename: Jong-Hoon
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D018920:Coculture Techniques; D004305:Dose-Response Relationship, Drug; D053595:Embryonic Stem Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D004785:Environmental Pollutants / Q000633:toxicity*; D053222:Fas Ligand Protein / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D051379:Mice; D010636:Phenols / Q000633:toxicity*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019014:fas Receptor / Q000235:genetics / Q000378:metabolism*
chemical_list: D004785:Environmental Pollutants; C491901:FAS protein, human; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D010636:Phenols; D012333:RNA, Messenger; D019014:fas Receptor; C474055:octylphenol; C025256:nonylphenol