title: TGF-β1 and BMP-4 carried by liposomes enhance the healing process in alveolar bone.
abstract: OBJECTIVE
  In this work we evaluated the bone-forming potential of BMP4, TGFβ1 and BMP4/TGFβ1 mixed by performing histological and morphometric analysis. We also evaluated the immunolabelling of fibronectin (FN) and collagen type III (Col III), two determinant proteins for the early phase of bone repair.
  
  
  METHODS
  Histological, histomorphometric and immunohistochemistry analysis were used to evaluate new bone and blood vessels formation as well as fibronectin and collagen type III expression. 112 male Wistar rats weighing 250-300g had their maxillary second molar extracted. Sockets filled with blood clot (BC) or treated with L (empty liposome), P (PBS), BP (BMP-4 in PBS) and TP (TGF-β1 in PBS), as well as with BL (BMP-4 in liposome) and TL (TGF-β1 in liposome) administered isolated or in association (BTL) were obtained. The animals were sacrificed at 3, 7, 14 and 21 days after surgery.
  
  
  RESULTS
  An increased percentage of bone trabeculae, and a higher number of blood vessels were observed in groups BL or TL administered isolated or in association when compared to groups BC, L, P, BP and TP. Fibronectin and collagen type III analysis revealed enhanced expression firstly detected at 3 days followed by a peak at 7 days. Lower levels of immunoreactivity were observed in the sockets filled with blood clot, and treated with L, P, BP and TP when compared with sockets from groups BL, TL and BTL.
  
  
  CONCLUSIONS
  The present study indicates growth factors carried by liposomes, either in isolated or associated forms, as successful enhancers of the healing process in rat tooth sockets. We also conclude that the expression of fibronectin and collagen type III increases during the early phases of bone repair.
authors.affiliation: Laboratory of Oral and Development Biology, Department of Morphology, Biological Sciences Institute, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Cynthia Lopes
authors.initials: CL
authors.lastname: Ferreira
authors.forename: Fernando Antônio Mauad de
authors.initials: FA
authors.lastname: Abreu
authors.forename: Gerluza Aparecida Borges
authors.initials: GA
authors.lastname: Silva
authors.forename: Frank Ferreira
authors.initials: FF
authors.lastname: Silveira
authors.forename: Luana Beatriz Araújo
authors.initials: LB
authors.lastname: Barreto
authors.forename: Tony de Paiva
authors.initials: Tde P
authors.lastname: Paulino
authors.forename: Melissa Nunes
authors.initials: MN
authors.lastname: Miziara
authors.forename: José Bento
authors.initials: JB
authors.lastname: Alves
mesh_terms: D000539:Alveolar Process / Q000098:blood supply / Q000187:drug effects* / Q000473:pathology; D000818:Animals; D001777:Blood Coagulation / Q000502:physiology; D055415:Bone Morphogenetic Protein 4 / Q000008:administration & dosage* / Q000494:pharmacology; D024061:Collagen Type III / Q000187:drug effects; D004337:Drug Carriers; D005353:Fibronectins / Q000187:drug effects; D008081:Liposomes; D008297:Male; D008437:Maxilla / Q000098:blood supply / Q000187:drug effects / Q000473:pathology / Q000601:surgery; D018919:Neovascularization, Physiologic / Q000187:drug effects; D010006:Osteoblasts / Q000187:drug effects / Q000473:pathology; D010010:Osteoclasts / Q000187:drug effects / Q000473:pathology; D010012:Osteogenesis / Q000187:drug effects*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014081:Tooth Extraction; D020390:Tooth Socket / Q000098:blood supply / Q000187:drug effects / Q000473:pathology / Q000601:surgery; D053773:Transforming Growth Factor beta1 / Q000008:administration & dosage* / Q000494:pharmacology; D014945:Wound Healing / Q000187:drug effects
chemical_list: C525811:Bmp4 protein, rat; D055415:Bone Morphogenetic Protein 4; D024061:Collagen Type III; D004337:Drug Carriers; D005353:Fibronectins; D008081:Liposomes; D053773:Transforming Growth Factor beta1