Gene Expression Analysis of Bone Tissue Grown on P(VDF-TrFE)/BT Membrane Implanted in Rat Calvarial Defects
Thursday, October 10, 2013
Helena Bacha Lopes DDS, Oral & Maxillofacial surgery, Cell Culture Laboratory, Ribeirão Preto Dental School, Ribeirão Preto, Brazil
Thiago de Santana Santos DDS, Msc, Oral and Maxillofacial Surgery, School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil., Ribeirão Preto, Brazil
Gileade Pereira Freitas DDS, Oral & Maxillofacial surgery, Cell Culture Laboratory, Ribeirão Preto Dental School, Ribeirão Preto, Brazil
Fabiola de Oliveira Msc, PhD, Oral and Maxillofacial Surgery, Biomolecular Laboratory Ribeirão Preto Dental School, Ribeirão Preto, Brazil
Rossano Gimenes Phd, Institute of Physics and Chemistry, Federal University of Itajubá, Itajubá, Brazil
Adalberto Luiz Rosa DDS, Msc, PhD, Oral and Maxillofacial Surgery, Cell Culture Laboratory, Ribeirão Preto Dental School, Ribeirão Preto, Brazil
Marcio Mateus Beloti DDS, Msc, PhD, Oral and Maxillofacial Surgery, Cell Culture Laboratory, Ribeirão Preto Dental School, Ribeirão Preto, Brazil
The principles of bone tissue engineering are contributing to the development of biomaterials to be employed in a range of therapies. Specifically in oral surgery, membranes are being used in different clinical situations such as treatment with dental implants, augmentation of alveolar bone and repair of traumatic and/or pathologic bone defects. In a previous study, we have showed that a novel poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) (Gimenes et al, 2004) membrane enhanced the majority of parameters related to tissue regeneration compared with polytetrafluorethylene (PTFE) membrane using three different cell lines, i.e.: osteoblasts, fibroblasts and keratinocytes (Teixeira et al., 2010). In the present study, we have investigated the in vivo gene expression of key osteoblastic markers in bone tissue grown on P(VDF-TrFE)/BT compared with PTFE (control) membranes. Rat calvarial bone defects (5-mm-diameter) were implanted with P(VDF-TrFE)/BT or PTFE membrane and after 4 and 8 weeks, gene expression of runt-related transcription factor 2 (Runx2), osterix (Osx), alkaline phosphatase (Alp), bone sialoprotein (Bsp) and osteocalcin (Oc) in bone tissue grown on membranes was evaluated by real-time PCR. Data were compared using the Kruskal-Wallis test, followed by Fischer test and the level of significance (p) was set at 0.05. The results presented in Table 1 indicated an enhanced osteoblast activity in bone tissue grown on P(VDF-TrFE)/BT compared with PTFE membrane, as evidenced by higher gene expression of Osx, Bsp and Oc at 4 weeks, and Runx2 and Oc at 8 weeks. Thus, P(VDF-TrFE)/BT membrane could be considered an advantageous biomaterial for bone tissue engineering applications.
Table 1.Gene expression on bone tissue grown on P(VDF-TrFE)/BT or PTFE membranes after 4 and 8 weeks
|
4 weeks
|
8 weeks
|
Gene
|
P(VDF-TrFE)/BT
|
PTFE
|
p
|
P(VDF-TrFE)/BT
|
PTFE
|
p
|
Runx2
|
0.93
|
1.00
|
ns
|
1.61
|
0.79
|
0.001
|
Osx
|
1.65
|
1.03
|
0.001
|
1.08
|
1.60
|
0.01
|
Alp
|
1.15
|
1.00
|
ns
|
0.52
|
0.60
|
0.05
|
Bsp
|
2.49
|
1.01
|
0.05
|
0.98
|
0.97
|
ns
|
Oc
|
3.06
|
1.00
|
0.001
|
1.87
|
1.50
|
0.005
|
ns – non-significant
Financial Support:FAPESP and CNPq
Reference
Gimenes, R.; Zaghete, M.A.; Bertolini, M.; Varela, J.A.; Coelho, L.O.; Silva Jr, N.F.Composites PVDF-TrFE/BT used as bioactive membranes for enhancing bone regeneration. In:Bar-Cohen Y, org. Proceedings of SPIE: Smart Structures and Materials. Bellinghan, WA, 2004. v.5385, p. 539-47.
Teixeira LN, Crippa GE, Trabuco AC, Gimenes R, Zaghete MA, Palioto DB, de Oliveira PT, Rosa AL, Beloti MM. In vitro biocompatibility of poly(vinylidene fluoride-trifluoroethylene)/barium titanate composite using cultures of human periodontal ligament fibroblasts and keratinocytes. Acta Biomater. 2010 Mar;6(3):979-89.
