Evaluation of the parameters associated to periodontal bone loss in animals submited to dietary magnesium intake deficiency

• Grant number: 10/17497-7
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2011
• End date: December 31, 2012
• Field of knowledge: Health Sciences - Dentistry - Periodontology
• Principal Investigator: Silvana Regina Perez Orrico
• Grantee: Silvana Regina Perez Orrico
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated researchers: Carlos Rossa Junior ; Gabriela Giro

Abstract

Magnesium plays a relevant role on bone tissue and this mineral deficiency results on systemic bone mass loss. However, there is a lack of studies evaluating the relationship of magnesium deficiency and periodontal bone loss. Therefore, this study will investigate the mechanisms involved on periodontal bone loss in rats with induced magnesium deficiency. For that purpose, this study comprised 30 rats assigned into 2 groups: control group (CTL) that received a standard diet with adequate magnesium content while test group (Mg) received the same diet except for a 90% reduction of magnesium on Day 0. At day 60th, a cotton thread were placed on the left mandible first molar in order to induce periodontal bone loss. The animals were euthanized 30 days after the placement of the cotton ligature. Periodontal bone loss was macroscopically evaluated by measuring vertical bone loss and the area of loss of bone on the first and second molars. After laboratory processing, 5 ¼m sections of both hemimandible (with or without the induction of the periodontal bone loss) will be stained with hematoxilin-eosin and it will be evaluated bone volume/total volume, osteoblast and osteoclast couting per surface. Activated caspase-3, PCNA (cell proliferation), osteopontin and osteocalcin (bone formation and mineralization biomarkers), RUNX2 (osteoblastic differentiation), TRAP (osteoclasts), iNOS (inducible nitric oxide synthase), eNOS (endothelial nitric oxide synthase), CD68, CD80 and CD86 will be detected by immunohistochemistry. Serum concetration of nitrite/nitrate will be also evaluated. (AU)