title: Effects of 1 alpha,25-dihydroxyvitamin D3 on the transglutaminase activity of transformed mouse epidermal cells in culture.
abstract: Induction of the transglutaminase activity of a transformed mouse epidermal cell line (PAM 212 cells) by 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25-(OH)2-D3), the active form of vitamin D3, was investigated. Addition of 1 alpha,25-(OH)2-D3 to a culture medium stimulated twice the transglutaminase activity at a concentration of 10(-7) M, but vitamin D3, prostaglandin E1, E2, and F2 alpha failed to show this induction. Phorbol 12-o-tetradecanoylphorbol-13-acetate (TPA) and dexamethasone also induced an increase in transglutaminase activity. Exposure to both 1 alpha,25-(OH)2-D3 and retinoic acid caused remarkably synergistic effects on the induction of transglutaminase in the PAM 212 cells. In contrast, simultaneous addition of 1 alpha,25-(OH)2-D3 and TPA was antagonistic and resulted in less than additive induction. Vitamin D3 also showed a similar but lesser effect. These results suggest that 1 alpha,25-(OH)2-D3 induces the transglutaminase activity via mechanisms disparate from those of retinoic acid and modifies epidermal differentiation.
authors.forename: S C
authors.initials: SC
authors.lastname: Lee
authors.forename: K
authors.initials: K
authors.lastname: Ikai
authors.forename: Y
authors.initials: Y
authors.lastname: Ando
authors.forename: S
authors.initials: S
authors.lastname: Imamura
mesh_terms: D000818:Animals; D002117:Calcitriol / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003907:Dexamethasone; D000078404:Epidermal Cells; D004817:Epidermis / Q000201:enzymology*; D051379:Mice; D011503:Transglutaminases / Q000378:metabolism*; D014212:Tretinoin
chemical_list: D014212:Tretinoin; D003907:Dexamethasone; D011503:Transglutaminases; D002117:Calcitriol