title: Leptin promotes dentin sialophosphoprotein expression in human dental pulp.
abstract: BACKGROUND
  Leptin, an inflammation-related adipokine, and its receptor (LEPR) are expressed in human dental pulp. Dentin sialophosphoprotein (DSPP) is involved in dentinogenesis and the dental pulp reparative response. The cell type expressing LEPR in dental human pulp and the resultant effect of the binding of leptin to LEPR remain unknown. This study describes the immmunohistochemical localization of LEPR and the effect of leptin on DSPP expression in human dental pulp.
  
  
  METHODS
  Twenty-five dental pulp specimens were obtained from freshly extracted caries-free and restoration-free human third molars. LEPR localization was examined by immunohistochemistry using the antihuman LEPR monoclonal antibody. The effect of leptin on DSPP expression was determined by immunoblot analysis and quantitative real-time polymerase chain reaction.
  
  
  RESULTS
  Immunoreactivity for LEPR concentrated in the odontoblast layer but was not evident in the central zone of the dental pulp. Leptin dose dependently stimulated DSPP expression. Western blot analysis revealed the presence of a protein with an apparent molecular weight of ∼00 kDa, the estimated molecular weight of DSPP. The expression of DSPP messenger RNA was confirmed by quantitative real-time polymerase chain reaction, and the size of the amplified fragments (298 bp) was confirmed by agarose gel electrophoresis.
  
  
  CONCLUSIONS
  The present study shows that human dental pulp is immunoreactive for LEPR, with the immunoreactivity concentrated in the odontoblast layer, and that leptin stimulates, in a dose-dependent manner, DSPP protein and messenger RNA (mRNA) expression in human dental pulp. These findings further support the functional role of leptin in the dentin mineralization process and/or in dental pulp reparative and immune responses.
authors.affiliation: Department of Stomatology (Endodontics Section), University of Sevilla, Sevilla, Spain.
authors.forename: Jénifer
authors.initials: J
authors.lastname: Martín-González
authors.affiliation: Department of Medical Biochemistry and Molecular Biology, Virgen Macarena University Hospital, Sevilla, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Pérez-Pérez
authors.affiliation: Department of Medical Biochemistry and Molecular Biology, Virgen Macarena University Hospital, Sevilla, Spain.
authors.forename: Flora
authors.initials: F
authors.lastname: Sánchez-Jiménez
authors.affiliation: Department of Normal and Pathologic Cytology and Histology, University of Sevilla, Sevilla, Spain.
authors.forename: Eduardo Manuel
authors.initials: EM
authors.lastname: Díaz-Parrado
authors.affiliation: Department of Normal and Pathologic Cytology and Histology, University of Sevilla, Sevilla, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: de Miguel
authors.affiliation: Department of Medical Biochemistry and Molecular Biology, Virgen Macarena University Hospital, Sevilla, Spain. Electronic address: margalet@us.es.
authors.forename: Víctor
authors.initials: V
authors.lastname: Sánchez-Margalet
authors.affiliation: Department of Stomatology (Endodontics Section), University of Sevilla, Sevilla, Spain. Electronic address: segurajj@us.es.
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Segura-Egea
mesh_terms: D000328:Adult; D003782:Dental Pulp / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis*; D006801:Humans; D020738:Leptin / Q000502:physiology*; D008875:Middle Aged; D009804:Odontoblasts / Q000378:metabolism; D010750:Phosphoproteins / Q000096:biosynthesis*; D012795:Sialoglycoproteins / Q000096:biosynthesis*; D055815:Young Adult; D000099311:Dentin Sialophosphoprotein
chemical_list: D016326:Extracellular Matrix Proteins; D020738:Leptin; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein
keywords: Cytokine; dentinogenesis; immunity; inflammation; leptin receptor; odontoblast; pulp biology; receptors