title: Enamel matrix derivative stimulates expression and secretion of resistin in mesenchymal cells.
abstract: In this study we wanted to identify the effect of enamel matrix derivative (EMD) on adipocytokines, so-called adipokines. Primary human cells of mesenchymal origin (osteoblasts, periodontal ligament cells, mesenchymal stem cells, and pulp cells) and hematopoietic origin (monocytes) were incubated with EMD. The levels of adipokines in cell culture medium were quantified using the Lincoplex human adipocyte panel (Luminex) and by real-time PCR of mRNA isolated from cell lysates. Rats were injected with 2 mg of EMD or saline intramuscularly every third day for 14 d. Blood samples were taken before and after injections, and the level of resistin in rat plasma was measured by ELISA. We found a dramatic increase in the secretion of resistin from mesenchymal stem cells, and verified this result in all the cells of mesenchymal origin tested. However, we observed no significant changes in the amount of resistin secreted from monocytes exposed to EMD compared with the control. Injections of EMD significantly enhanced the circulating levels of resistin in rats, and EMD also significantly enhanced the activity of the resistin promoter in transfected mesenchymal stem cells, indicating a direct effect on resistin expression. Our results indicate that resistin may play a role in mediating the biological effect of EMD in mesenchymal tissues.
authors.affiliation: Department of Biomaterials, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Maria V
authors.initials: MV
authors.lastname: Obregon-Whittle
authors.forename: Astrid K
authors.initials: AK
authors.lastname: Stunes
authors.forename: Sofia
authors.initials: S
authors.lastname: Almqvist
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Brookes
authors.forename: James D
authors.initials: JD
authors.lastname: Lees
authors.forename: James D
authors.initials: JD
authors.lastname: Lee
authors.forename: Unni
authors.initials: U
authors.lastname: Syversen
authors.forename: Staale P
authors.initials: SP
authors.lastname: Lyngstadaas
authors.forename: Janne E
authors.initials: JE
authors.lastname: Reseland
mesh_terms: D054392:Adipokines / Q000096:biosynthesis* / Q000235:genetics; D000704:Analysis of Variance; D000818:Animals; D001854:Bone Marrow Cells / Q000378:metabolism; D002478:Cells, Cultured; D003746:Dental Enamel Proteins / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry / Q000494:pharmacology*; D003782:Dental Pulp / Q000166:cytology / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D007273:Injections, Intramuscular; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D009000:Monocytes / Q000378:metabolism; D010006:Osteoblasts / Q000378:metabolism*; D010513:Periodontal Ligament / Q000166:cytology / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D052243:Resistin / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D014162:Transfection
chemical_list: D054392:Adipokines; D003746:Dental Enamel Proteins; D052243:Resistin; C109069:enamel matrix proteins