title: Actin stabilization induces apoptosis in cultured porcine epithelial cell rests of Malassez.
abstract: OBJECTIVE
  To test whether actin stabilization by jasplakinolide induces inhibition of cell viability and apoptosis in epithelial cell rests of Malassez (ERM).
  
  
  METHODS
  ERM derived from porcine were spread in a 96-well dish (5 × 10(4) /well) using Dulbecco's modified Eagle's medium. The actin-specific stabilization reagent, jasplakinolide, was incorporated into the culture medium and incubated for 24 h. To evaluate cell viability, the WST-1 assay was carried out and absorption (450 nm) was measured. To detect apoptotic cells, monoclonal antibody to single-strand DNA (ssDNA) was used and absorption (405 nm) was measured. Actin stabilization and apoptosis induced by jasplakinolide were morphologically investigated by staining with Alexa Fluor 568 phalloidin and observed under a fluorescent microscope. As a negative control, DMSO was used instead of jasplakinolide. Differences between the jasplakinolide-treated group and the control group were analysed statistically using the Student's t-test.
  
  
  RESULTS
  Cell viability decreased in a concentration-dependent manner, and cell viability in the jasplakinolide-treated ERM was lower than that in nontreated ERM (n = 16, P < 0.01). Apoptotic cells in the jasplakinolide-treated ERM were more frequently detected compared to that in nontreated ERM (n = 16, P < 0.01). Morphologically, shrinkage, irregular forms and fragmentation of nuclei suggesting apoptotic bodies were observed in jasplakinolide-treated ERM, whilst actin filaments were extended in non-treated ERM.
  
  
  CONCLUSIONS
  Actin stabilization by jasplakinolide inhibited cell viability and induced apoptosis in epithelial cell rests of Malassez.
authors.affiliation: Department of Endodontics and Clinical Cariology, Tokyo Dental College, Tokyo, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Aida
authors.affiliation: Department of Endodontics and Clinical Cariology, Tokyo Dental College, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ushikubo
authors.affiliation: Department of Endodontics and Clinical Cariology, Tokyo Dental College, Tokyo, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Kobayashi
authors.affiliation: Department of Endodontics and Clinical Cariology, Tokyo Dental College, Tokyo, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Sako
authors.affiliation: Department of Endodontics and Clinical Cariology, Tokyo Dental College, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Suehara
authors.affiliation: Department of Endodontics and Clinical Cariology, Tokyo Dental College, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Furusawa
authors.affiliation: Department of Endodontics and Clinical Cariology, Tokyo Dental College, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Muramatsu
mesh_terms: D000199:Actins / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D047630:Depsipeptides / Q000494:pharmacology; D004847:Epithelial Cells / Q000187:drug effects / Q000502:physiology*; D010513:Periodontal Ligament / Q000166:cytology / Q000502:physiology*; D013552:Swine; D014092:Tooth Root / Q000166:cytology / Q000502:physiology
chemical_list: D000199:Actins; D047630:Depsipeptides; C057531:jasplakinolide
keywords: actin stabilization; apoptosis; epithelial cell rests of Malassez; jasplakinolide