Basic-fibroblast growth factor ve dexamethasone'un periodontal ligament hücrelerinin proliferasyonu, protein miktarı ve tip I kollajen mRNA ekspresyonu üzerine etkisi
Küçük Resim Yok
Tarih
2004
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Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Amaç: Periodontal hastalıkların tedavisinde temel amaç, periodontal ataçmanın mineralize ve yumuşak doku bileşenlerinin rejenerasyonudur. Periodontal Ligamentin (PDL), ideal rejenerasyondan primer olarak sorumlu hücre grubunu içerdiği, yeni sement ve yeni kemik formasyonunu sağlayabilecek kapasitesi olduğu gösterilmiştir. PDL, sementoblast ve/veya osteoblasta farklılaşabilen, heterojen bir hücre popülasyonuna sahiptir. Son zamanlarda PDL'nin karak-terizasyonu ile ilgili çalışmalar, bu hücrelerin osteo-blast benzeri özelliklerinin belirlenmesi ve periodontal ligamentde osteoblastik hücre popülasyonunu uyarabilecek büyüme faktörlerinin tespit edilmesi yönünde yoğunlaşmıştır. Polipeptid büyüme ve farklılaşma faktörleri, yara iyileşmesi sürecinin düzenlenmesi ve uyarılmasında önemli rol oynayan biyolojik yönlendiricilerdir. Bu çalışmanın amacı, basic-Fibroblast Growth Factor (b-FGF) ve Dexamethasone (Dex) gibi biyolojik faktörlerin, PDL hücrelerinin fonksiyonlarına ve tip I kollajen mRNA ekspresyonlarına etkilerinin belirlenmesidir. Gereç ve Yöntemler: PDL hücreleri ortodontik nedenlerle çekilen premolar dişlerden elde edildi. İlk aşamada PDL hücrelerine farklı konsantrasyonlarda b-FGF ( 0.1, 1, 10 ve 50 ng/ml) uygulanarak etkin konsantrasyon saptandı. Takiben, PDL hücreleri, b-FGF (1 ng/ml), Dex (10-7 M) ve bu faktörlerin kombinasyonu ile muamele edildi. PDL hücrelerinin proliferas-yonu hemositometre ile ve total protein miktarı Lowry metodu ile 0, 3, 7, 10 ve 15. günlerde değerlendirildi. Hücrelerin mitotik aktivitelerinin tayini 3H thymi-dine kullanılarak 24. saatte gerçekleştirildi. Tüm gruplardan 0, 3 ve 7. günlerde total RNA izole edilerek, 'Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR)' tekniği ile tip I kollajen mRNA ekspresyonları belirlendi. Bulgular: PDL hücreleri için b-FGF'nin etkin konsantrasyonunun 1 ng/ml olduğu belirlendi. Üçüncü günde gruplar arasında anlamlı bir fark izlenmezken, b-FGF'nin, hücrelerin proliferasyonunu 10. ve 15. günlerde diğer gruplarla kıyaslandığında istatistiksel olarak anlamlı şekilde artırdığı gözlendi (p0.001). b-FGF'nin diğer gruplarla kıyaslandığında tüm zaman periyotlarında PDL hücrelerinin total protein miktarını artırdığı ancak bu artışın 3. ve 15. günlerde istatistiksel olarak anlamlı olduğu tespit edildi (p0.001). Dex'in tek başına hem proliferasyonu hem de protein miktarını anlamlı şekilde inhîbe ettiği gözlendi, b-FGF'nin PDL hücrelerinin mitotik aktivitesini 24. saatte diğer gruplarla kıyaslandığında anlamlı şekilde artırdığı saptandı. İnsan PDL hücrelerin, tip I kollajen mRNA ekspresyonunun, 3. günde b-FGF ve Dexb-FGF ile muamele edilen gruplarda, kontrol grubu ile kıyaslandığında azaldığı, 7. günde ise b-FGF'nin kontrol grubundakine benzer şekilde tip I kollajen mRNA ekspresyonu sergilediği tespit edildi. Tek başına Dex ile muamele edilen grupta ise kontrol grubu ile kıyaslandığında hem 3. günde, hem de 7. günde tip I kollajen mRNA ekspresyonunun çok az miktarda inhibe olduğu gözlendi. Sonuç: b-FGF ve/veya Dex'in PDL hücrelerinin aktivitesini farklı bir şekilde etkileyebildiğini ve b-FGF'nin periodontal rejenerasyon sürecinde hücrelerin biyolojik aktivitesini artırabileceğini düşündürmektedir. Ancak, bu faktörlerin PDL hücrelerine olan etki mekanizmasının açıklığa kavuşmasına yönelik daha fazla araştırma gerekmektedir.
Objective: A primary objective in the treatment of periodontal disease is the regeneration of the mineralized and soft connective tissue components of the attachment apparatus. The periodontal ligament (PDL) has been shown to possess the ability; to regenerate both new cementum and alveolar bone. The PDL has a heterogeneous cell population and some of these cells may be capable to differentiate to cementoblasts and/or osteoblasts. Recent studies point on characterizing PDL cells have been directed at determining their osteoblast-like properties and identifying growth factors that induce osteoblastic cell population in the PDL. Polypeptide growth and differentiation factors are a class of biological modifiers which have been shown to play a critical role in the stimulation and regulation of the wound healing process. The purpose of this study was to determine the possible effects of basic-Fibroblast Growth Factor (b-FGF) and Dexamethasone (Dex) on the PDL cells. Materials and Methods: PDL cells were obtained from premolar teeth extracted for orthodontic reasons. Cells were exposed to different concentrations of b-FGF (0.1, 1, 10, 50 ng/ml) to determine the optimum concentrations. As a second step, PDL cells were treated either with b-FGF (1 ng/ml) or Dex (10-7 M) or the combination of these factors. The cell counts and amount of protein (Lowry method) of the cultures were determined on the days 0, 3, 7, 10 and 15. Mitotic activities of PDL cells were evaluated by measuring 3H thymi-dine incorporation at 24 hours using b-scintillation counter. Moreover, total RNA was isolated from all groups on the days 0, 3 and 7 By using Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) tecnique, collagen type I mRNA expression of PDL cells for each group was examined. Results: The data indicated that the optimum concentration of b-FGF for the proliferation of PDL cells was 1 ng/ml. While there was no significant difference on day 3, b-FGF significantly induced proliferation of PDL cells when compared to other groups on day 10 and 15 (p<0.001). b-FGF stimulated total protein amount of PDL cells versus other groups at all time periods but increase of protein amount was statistically significant on day 3 and 15 (p<0.001). Treatment of Dex alone significantly inhibited both the amount of protein and proliferation of PDL cells. After 24 hours treatment, 1 ng/ml b-FGF produced significant increase in 3H thymidine incorporation into DNA when compared to other groups. It was observed that the levels of collagen type I mRNA expression of human PDL cells was downregulated by b-FGF and Dexb-FGF treatment in comparison with control cultures on day 3. Cells exposed to b-FGF demonstrated similar collagen type I mRNA expression with control group on day 7. In cultures solely treated with Dex, mRNA expression of collagen type I was slightly inhibited when compared to control group on days 3 and 7. Conclusion: These results indicate that b-FGF and/or Dex influence PDL cells activity differently and confirm that b-FGF may enhance the biological activity of cells in periodontal regeneration process. Obviously, more researchs are necessary to clarify the mechanism of the effects of these factors on PDL cells.
Objective: A primary objective in the treatment of periodontal disease is the regeneration of the mineralized and soft connective tissue components of the attachment apparatus. The periodontal ligament (PDL) has been shown to possess the ability; to regenerate both new cementum and alveolar bone. The PDL has a heterogeneous cell population and some of these cells may be capable to differentiate to cementoblasts and/or osteoblasts. Recent studies point on characterizing PDL cells have been directed at determining their osteoblast-like properties and identifying growth factors that induce osteoblastic cell population in the PDL. Polypeptide growth and differentiation factors are a class of biological modifiers which have been shown to play a critical role in the stimulation and regulation of the wound healing process. The purpose of this study was to determine the possible effects of basic-Fibroblast Growth Factor (b-FGF) and Dexamethasone (Dex) on the PDL cells. Materials and Methods: PDL cells were obtained from premolar teeth extracted for orthodontic reasons. Cells were exposed to different concentrations of b-FGF (0.1, 1, 10, 50 ng/ml) to determine the optimum concentrations. As a second step, PDL cells were treated either with b-FGF (1 ng/ml) or Dex (10-7 M) or the combination of these factors. The cell counts and amount of protein (Lowry method) of the cultures were determined on the days 0, 3, 7, 10 and 15. Mitotic activities of PDL cells were evaluated by measuring 3H thymi-dine incorporation at 24 hours using b-scintillation counter. Moreover, total RNA was isolated from all groups on the days 0, 3 and 7 By using Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) tecnique, collagen type I mRNA expression of PDL cells for each group was examined. Results: The data indicated that the optimum concentration of b-FGF for the proliferation of PDL cells was 1 ng/ml. While there was no significant difference on day 3, b-FGF significantly induced proliferation of PDL cells when compared to other groups on day 10 and 15 (p<0.001). b-FGF stimulated total protein amount of PDL cells versus other groups at all time periods but increase of protein amount was statistically significant on day 3 and 15 (p<0.001). Treatment of Dex alone significantly inhibited both the amount of protein and proliferation of PDL cells. After 24 hours treatment, 1 ng/ml b-FGF produced significant increase in 3H thymidine incorporation into DNA when compared to other groups. It was observed that the levels of collagen type I mRNA expression of human PDL cells was downregulated by b-FGF and Dexb-FGF treatment in comparison with control cultures on day 3. Cells exposed to b-FGF demonstrated similar collagen type I mRNA expression with control group on day 7. In cultures solely treated with Dex, mRNA expression of collagen type I was slightly inhibited when compared to control group on days 3 and 7. Conclusion: These results indicate that b-FGF and/or Dex influence PDL cells activity differently and confirm that b-FGF may enhance the biological activity of cells in periodontal regeneration process. Obviously, more researchs are necessary to clarify the mechanism of the effects of these factors on PDL cells.
Açıklama
Anahtar Kelimeler
Diş Hekimliği
Kaynak
Hacettepe Dişhekimliği Fakültesi Derg.(. Clinical Dentistry and Research)
WoS Q Değeri
Scopus Q Değeri
Cilt
28
Sayı
1
