title: 1,25-dihydroxyvitamin D inhibits vitamin E succinate-induced apoptosis in C3H10T1/2 cells but not Harvey ras-transfected cells.
abstract: In this study, the effect of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on regulation of apoptosis was compared in control C3H10T1/2 mouse fibroblast cells and those transfected with the Harvey ras oncogene. A known apoptotic stimulator, vitamin E succinate (VES), reduced cell number in a time- and dose-dependent manner in both cell types. In an assay for viable cells, there were significantly more C3H10T1/2 cells cotreated with VES and 1,25(OH)2D3 (-5.0 +/- 10.5% of vehicle-treated controls) compared to VES alone treated cells (-60.8 +/- 5.6%). In contrast, 1,25(OH)2D3 did not change the percentage of viable cells following treatment by VES in ras-transfected cells [-67.3 +/- 7.5%, VES alone compared to 57.3 +/-v 15.7% with VES and 1,25(OH)2D3 ]. Further studies confirmed that 1,25(OH)2D3 inhibited VES-mediated apoptosis (1.27 +/- 0.34-fold over vehicle control) compared to VES treatment alone (2.29 +/- 0.56-fold increase) in C3H10T1/2 cells, but not in ras-transfected cells [3.07 +/- 0.43-fold increase, VES treatment alone; 3.64 +/- 0.42-fold increase, VES and 1,25(OH)2D3]. Both C3H10T1/2 and ras-transfected cells treated with VES had increased concentrations of cellular VES with very little change in a-tocopherol, indicating that the cells took up VES intact. In addition, both cell lines contained similar levels of nuclear vitamin D receptor (VDR); however, the ras-transfected cells had reduced VDRE transcriptional activity. In conclusion, VES exerts its effect intact and 1,25(OH)2D3 preferentially protects C3H10T1/2 cells, whereas ras-transformed cells were not protected from VES-mediated apoptosis.
authors.affiliation: Department of Foods and Nutrition, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Lynn
authors.initials: L
authors.lastname: Stedman
authors.forename: Kwangok P
authors.initials: KP
authors.lastname: Nickel
authors.forename: S Sianna
authors.initials: SS
authors.lastname: Castillo
authors.forename: Juan
authors.initials: J
authors.lastname: Andrade
authors.forename: John R
authors.initials: JR
authors.lastname: Burgess
authors.forename: Dorothy
authors.initials: D
authors.lastname: Teegarden
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002117:Calcitriol / Q000378:metabolism / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005434:Flow Cytometry / Q000379:methods; D011905:Genes, ras / Q000235:genetics; D006801:Humans; D051379:Mice; D018167:Receptors, Calcitriol / Q000378:metabolism; D024505:Tocopherols; D015533:Transcriptional Activation; D014162:Transfection; D014407:Tumor Cells, Cultured; D014810:Vitamin E / Q000009:adverse effects* / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D018167:Receptors, Calcitriol; D014810:Vitamin E; D002117:Calcitriol; D024505:Tocopherols