title: Platelets increase while serum reduces the differentiation and activity of osteoclasts in vitro.
abstract: Platelets modulate formation of osteoclasts and osteoblasts, but research with different preparations of platelets remains inconclusive. Here, we assessed whether serum components modulate the effect of platelet preparations. In murine bone marrow cultures, osteoclastogenesis was investigated in the presence of platelet-released supernatant (PRS), serum containing PRS (SC-PRS), and serum. Osteoclastogenesis was quantified by the numbers of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells, TRAP activity and resorption assays. Also human osteoclastogenesis assays were performed. Viability and proliferation were tested by MTT and (3) [H]thymidine incorporation assays, respectively. Osteoblastogenesis was assessed by histochemical staining for alkaline phosphatase-of murine bone marrow cultures and human MG63 cells. We found PRS to increase the number of TRAP(+) multinucleated cells in the early phase and TRAP activity in the later phase of osteoclastogenesis. SC-PRS and serum decreased the number and activity of TRAP(+) multinucleated cells. Both serum containing preparations reduced viability and proliferation of hematopoietic progenitors. PRS decreased the numbers of alkaline phosphatase-positive colonies while SC-PRS and serum increased osteoblastmarkers in MG63. Proliferation of MG63 was stimulated by all preparations. These results show that activated platelets support osteoclastogenesis, while platelet preparations that contain serum components decrease osteoclastogenesis and increase osteoblastogenesis in vitro, suggesting that serum components modulate the effects of platelets on osteoclastogenesis and osteoblastogenesis.
authors.affiliation: Department of Conservative Dentistry and Periodontology, Medical University of Vienna, Vienna, Austria.
authors.forename: Hermann
authors.initials: H
authors.lastname: Agis
authors.forename: Stefan
authors.initials: S
authors.lastname: Schröckmair
authors.forename: Carmine
authors.initials: C
authors.lastname: Skorianz
authors.forename: Michael B
authors.initials: MB
authors.lastname: Fischer
authors.forename: Georg
authors.initials: G
authors.lastname: Watzek
authors.forename: Reinhard
authors.initials: R
authors.lastname: Gruber
mesh_terms: D000328:Adult; D000818:Animals; D001792:Blood Platelets / Q000166:cytology / Q000502:physiology*; D001798:Blood Proteins / Q000378:metabolism / Q000494:pharmacology*; D001854:Bone Marrow Cells / Q000166:cytology / Q000502:physiology; D001862:Bone Resorption / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D049109:Cell Proliferation; D003470:Culture Media / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000502:physiology; D051379:Mice; D010006:Osteoblasts / Q000166:cytology / Q000502:physiology; D010010:Osteoclasts / Q000166:cytology / Q000502:physiology*; D010976:Platelet Count; D053657:Platelet-Rich Plasma; D015398:Signal Transduction / Q000502:physiology
chemical_list: D001798:Blood Proteins; D003470:Culture Media
keywords: bone resorption; osteoclast; plasma; platelet-rich plasma; platelets