title: Effect of cyclosporin A on proliferation and differentiation of human periodontal ligament cells.
abstract: OBJECTIVE
  Cyclosporin A (CsA) is widely used to prevent rejection after organ transplantation. However, it also causes several side-effects, including gingival overgrowth and bone resorption. Cellular mechanisms underlying the effect of CsA on periodontal tissue remain unclear. In this study, we investigated the effect of CsA on the proliferation and expression of characteristic markers in periodontal ligament cells (PDLs).
  
  
  METHODS
  The proliferation and viability of PDLs were measured by direct cell counting and 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide assay, respectively. mRNA expression levels of the specific proteins alkaline phosphatase (ALP), osteocalcin (OC) and collagen type 1 (Coll-1) were quantified using real-time polymerase chain reaction. Finally, ALP activity of PDLs was investigated using a specific colorimetric assay.
  
  
  RESULTS
  We found that proliferation of PDLs was stimulated by 0.01–0.1 μg/ml CsA and unaffected by 1 μg/ml CsA. The viability of PDLs was increased by 0.1 μg/ml CsA and not affected by 0.01 μg/ml and 1 μg/ml CsA. Furthermore, the mRNA expression levels of ALP, OC and Coll-1 in PDLs were significantly increased upon stimulation with 0.1 μg/ml CsA for 24 h or by stimulation with 0.01 μg/ml CsA for 48 h. In contrast, significantly lower expression levels of all three proteins in PDLs were observed upon stimulation with 1 μg/ml CsA for 48 h. The ALP activity of PDLs exhibited a similar pattern of changes upon CsA stimulation.
  
  
  CONCLUSIONS
  Our data demonstrated that CsA may influence both the proliferation and differentiation of human PDLs, which may play an important role in the homeostasis of periodontal tissue.
authors.affiliation: Department of Periodontology, Bernhard Gottlieb School of Dentistry, Medical University of Vienna, Vienna, Austria. oleh.andrukhov@meduniwien.ac.at
authors.forename: Oleh
authors.initials: O
authors.lastname: Andrukhov
authors.forename: Michael
authors.initials: M
authors.lastname: Matejka
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Rausch-Fan
mesh_terms: D000469:Alkaline Phosphatase / Q000096:biosynthesis; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D024042:Collagen Type I / Q000096:biosynthesis; D016572:Cyclosporine / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000494:pharmacology*; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism; D015675:Osteocalcin / Q000096:biosynthesis; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D018709:Statistics, Nonparametric
chemical_list: D024042:Collagen Type I; D007166:Immunosuppressive Agents; D015675:Osteocalcin; D016572:Cyclosporine; D000469:Alkaline Phosphatase