title: Apoptosis as a mechanism of 2-chloroethylethyl sulfide-induced cytotoxicity.
abstract: Apoptosis is a mode of active cell death. We have examined whether 2-chloroethylethyl sulfide (CEES), a sulfur vesicating agent, triggers apoptosis as a cytotoxic mechanism. Incubation of thymocytes with CEES, resulted in an induction of apoptotic features of cell death. Treatment of cells with 100 microM CEES for 5 h increased DNA fragmentation to approximately 40% of control. The fragmentation of DNA was visualized by agarose gel electrophoresis. It showed ladder pattern of DNA fragmentation, which indicates internucleosomal cleavage of DNA. Further evidence of apoptosis was observed in morphological changes of nuclei by using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method. The percentage of TUNEL positive cells was dependent upon CEES concentrations. CEES induced the classical morphological features of apoptosis in nucleus. These features were accompanied by condensation of chromatin, which arranged in sharply declined clumps and fragmentation of nucleus. To study requirement for synthesis of new protein in CEES-induced apoptosis, we studied the effect of cycloheximide for apoptotic activity. This protein synthesis inhibitor did not suppress the CEES-induced apoptotic activity. Taken together, these results suggest that CEES-induced apoptosis as a cytotoxicmechanism and this process occurs independent of synthesis of new protein.
authors.affiliation: CBR Department, Agency for Defense Development, Yuseong, Taejon, South Korea.
authors.forename: G H
authors.initials: GH
authors.lastname: Hur
authors.forename: Y B
authors.initials: YB
authors.lastname: Kim
authors.forename: D S
authors.initials: DS
authors.lastname: Choi
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: S
authors.initials: S
authors.lastname: Shin
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002467:Cell Nucleus / Q000187:drug effects; D002478:Cells, Cultured; D002843:Chromatin / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004587:Electrophoresis, Agar Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005821:Genetic Techniques; D007150:Immunohistochemistry; D051379:Mice; D008813:Mice, Inbred ICR; D009151:Mustard Gas / Q000031:analogs & derivatives* / Q000633:toxicity; D009707:Nucleosomes / Q000378:metabolism; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D013950:Thymus Gland / Q000187:drug effects*
chemical_list: D002843:Chromatin; D009707:Nucleosomes; D011500:Protein Synthesis Inhibitors; C031278:2-chloroethyl ethyl sulfide; D003513:Cycloheximide; D009151:Mustard Gas