Effect of alendronate on endochondral ossification in mandibular condyles of growing rats

Autor(es)

Bradaschia-Correa, V. ^[1] ; Barrence, F. A. C. ^[2] ; Ferreira, L. B. ^[1] ; Massa, L. F. ^[1] ; Arana-Chavez, V. E. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Dent, Div Oral Biol, BR-05508 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Biomed Sci, Dept Cell & Dev Biol, BR-05508 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: EUROPEAN JOURNAL OF HISTOCHEMISTRY; v. 56, n. 2, p. 149-153, 2012.
• Citações Web of Science: 3

Resumo

The replacement of the calcified cartilage by bone tissue during the endochondral ossification of the mandibular condyle is dependent of the resorbing activity of osteoclats. After partial resorption, calcified cartilage septa are covered by a primary bone matrix secreted by osteoblasts. Osteoadherin (OSAD) is a small proteoglycan present in bone matrix but absent in cartilage during the endochondral ossification. The aim of this study was to analyze the effect of alendronate, a drug known to inhibit bone resorption by osteoclasts, on the endochondral ossification of the mandibular condyle of young rats, by evaluating the distribution of osteoclasts and the presence of OSAD in the bone matrix deposited. Wistar newborn rats (n = 45) received daily injections of alendronate (n = 27) or sterile saline solution as control (n = 18) from the day of birth until the ages of 4, 14 and 30 days. At the days mentioned, the mandibular condyles were collected and processed for transmission electron microscopy analysis. Specimens were also submitted to tartrate resistant acid phosphatase (TRAP) histochemistry and ultrastructural immunodetection of OSAD. Alendronate treatment did not impede the recruitment and fusion of osteoclasts at the ossification zone during condyle growth, but they presented inactivated phenotype. The trabeculae at the ossification area consisted of cartilage matrix covered by a layer of primary bone matrix that was immunopositive to OSAD at all time points studied. Apparently, alendronate impeded the removal of calcified cartilage and maturation of bone trabeculae in the mandibular ramus, while in controls they occurred normally. These findings highlight for giving attention to the potential side-effects of bisphosphonates administered to young patients once it may represent a risk of disturbing maxillofacial development. (AU)

• Processo FAPESP: 06/60094-5 - Estudo da erupção dos molares de ratos jovens tratados com bisfosfonatos através de imunocitoquímica, imunofluorescência e Western blot
• Beneficiário: Vivian Bradaschia Corrêa
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 09/54853-9 - Estudo do efeito do alendronato sodico na expressao de moleculas reguladoras da remodelacao do processo alveolar durante a erupcao dos molares de ratos jovens.
• Beneficiário: Victor Elias Arana-Chavez
• Modalidade de apoio: Auxílio à Pesquisa - Regular