Selective cyclooxygenase-2 inhibition prevents bone resorption

Abstract

ABSTRACT:The aim of the present work was to evaluate the effect of a selective cyclooxygenase-2 (COX-2) inhibitor (meloxicam) on the alveolar bone loss progression in experimentally induced periodontitis. Forty (40) Wistar rats were separated into 8 experimental groups (n = 5). Cotton ligatures were placed at the gingival margin level of the lower right first molars of some rats. Four groups were treated for 5 or 15 days with an oral dose of 15 mg/kg of body weight/day of the selective COX-2 inhibitor. The other groups were used as positive control (sham) or negative control in each experimental period. Standardized digital radiographs were taken after sacrifice at 5 and 15 days to measure the amount of bone loss at the mesial root surface of the first molar tooth in each rat. The treatment with meloxicam did not induce weight alteration or other visible systemic manifestations. One way analysis of variance (ANOVA) indicated that groups treated with meloxicam, after 5 days, had significantly less alveolar bone loss (p < 0.05) when compared with control groups. On the other hand, no significant differences in bone loss were observed after 15 days of treatment with meloxicam. These data provide evidence that systemic therapy with meloxicam can modify the progression of experimentally induced periodontitis in rats during the initial experimental period. DESCRIPTORS: Alveolar bone loss; Anti-inflammatory agents, non-steroidal; Cyclooxygenase inhibitors; Periodontitis; Radiography, dental. RESUMO:O objetivo deste trabalho foi avaliar o efeito de um inibidor seletivo da cicloxigenase-2 (COX-2) (meloxicam) na progressão da perda óssea alveolar durante o desenvolvimento da doença periodontal experimental induzida. Quarenta (40) ratos Wistar foram separados em 8 grupos experimentais (n = 5). Ligaduras de fio de algodão foram colocadas na margem gengival do primeiro molar inferior direito de alguns ratos. Quatro grupos foram tratados por 5 ou 15 dias com uma dose oral de 15 mg/kg de peso corporal/dia do inibidor seletivo de COX-2. Os outros grupos foram usados como controle positivo (sham) e controle negativo dentro de cada período experimental. Radiografias digitais padronizadas foram realizadas para medir a perda óssea na região mesial do primeiro molar inferior de cada rato. O efeito do tratamento com meloxicam não induziu alteração de peso ou outras manifestações sistêmicas visíveis. A Análise de Variância (ANOVA) indicou que os grupos tratados com meloxicam após 5 dias apresentaram perda óssea alveolar significativamente menor (p < 0,05). Por outro lado, a perda óssea não foi significativa após 15 dias de tratamento com meloxicam. Os dados apresentados no presente trabalho sugerem que o tratamento sistêmico com meloxicam pode modificar a progressão da periodontite experimental em ratos no período experimental inicial.

Signaling pathways associated with the expression of inflammatory mediators activated during the course of two models of experimental periodontitis

“…In spite of subtle and sometimes non-statistically significant differences, this trend of decreasing severity of inflammation in the ligature model may suggest an attempt of damage repair that is noticeable only on ligature sites. Since inflammation associated with ligatures initiate on the gingival margin because of both mechanical trauma as well as increased accumulation of microorganisms, we speculate that after the initial damage, already documented by our research group at day 5 after ligature placement (Holzhausen et al 2002;Nassar et al 2005), may in fact increase the distance between the bone crest area and the ligatures. This hypothesis would also explain why this trend of decreasing severity is much more subtle on the submarginal area, which is in greater proximity to the ligature.…”

Anti-inflammatory effect of α, β-Amyrin, a pentacyclic triterpene from Protium heptaphyllum in rat model of acute periodontitis

“…fibroblast production, which is greatly influenced by bone resorbing cytokine IL-6 (Tipton et al, 2003). Several data in literature provide evidence that systemic therapy with COX-2 inibitors such as meloxicam and etoricoxib can retard the progression of experimentally induced periodontitis in rats during the initial experimental period and also retard bone resorption at a later stage (Holzhausen et al, 2005;Nassar et al, 2005). It remains to be seen in a future study whether or not a, b-amyrin blocks bone resorption in the chronic phase of periodontitis.…”

Targeting mRNA Stability Arrests Inflammatory Bone Loss

“…The importance of cytokines in periodontal disease progression was demonstrated in nonhuman primates when specific antagonists of IL-1 and TNF-α inhibited the progression of bone loss in an experimental periodontitis model 14. Additionally, in a ligature-induced periodontal model of bone loss in rats, meloxicam, a selective COX-2 inhibitor, was capable of inhibiting bone loss in rats 13. More recently, inhibitors of p38 MAPK have been shown to prevent or arrest periodontal bone loss in experimental periodontitis models through selective inhibition of inflammatory cytokines including IL-6, TNF-α, and IL-1β 15,16…”