Connexin 43 induces odontoblast differentation in incisors of rats with dental fluorosis

• Autores: Fontanetti, Pablo Alejandro; Interlandi, Victoria; Gallará, Raquel Vivian; Ponce, Rubén Hugo; Centeno, Viviana Andrea
• Año de publicación: 2015
• Idioma: inglés
• Tipo de recurso: documento de conferencia
• Materia: Fluorosis dental; Connexin 43
• Institución: Universidad Nacional de Córdoba

Fil: Fontanetti, Pablo Alejandro. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Introducción a la Química y Física Biológicas A; Argentina.
Fil: Interlandi, Victoria. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Fil: Gallará, Raquel Vivian. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Fil: Ponce, Rubén Hugo. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Fil: Centeno, Viviana Andrea. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Molecules of intercellular communication, such as connexin 43 (Cx43), are important during dentinogenesis since they control cellular growth and differentiation. Excessive ingestion of fluoride (F-) during the phase of dental mineralization generates alterations in the structure and function of cells from different dental tissues. In previous works, we demonstrated that chronic ingestion of F- through drinking water produced an increase in the activity of alkaline phosphatase and in the levels of ARNm of Cx43, osteocalcin and dentin sialophosphoprotein in pulp of rat´s incisor. OBJECTIVE: To study the effect of chronic exposure to F- on the protein expression of Cx43 and morphological and molecular indicators of odontoblast differentiation. METHODS: Male Wistar rats (n=6 per group) drank water during 8 weeks, with different concentrations of F- in the form of NaF: a) 0.3 mg/L (Control), b) 10 mg/L (Treated). Subsequently, all animals were euthanized; their mandibles were extracted for histological processing and the upper maxilla to obtain incisor´s pulp tissue. Protein expression of Cx43 was analyzed by immunohistochemistry. On digital microphotographs, histomorphometric parameters were analyzed: number of odontoblasts/µm2, ratio nucleus/cytoplasm, and predentin thickness. Total ARN was extracted from pulp tissue and gene expression of Hsp25, specific marker of odontoblast differentiation, was analyzed by RT-PCR. Data were analyzed by Student ?t? test. RESULTS: Immunoreactivity of Cx43 was evident in odontoblasts and increased by exposure to F- compared to controls. The F- dose used in the treated group did not modify the number of odontoblasts/ µm2, although it increased odontoblast differentiation, evidenced by the decrease in the ratio nucleus/cytoplasm of odontoblasts and expression of the differentiation marker Hsp25. CONCLUSION: Chronic exposure to high dose of F- could induce odontoblast differentiation mediated by Cx43, producing cells more capable to express genes and/or proteins essential for mineralization process.This work was funded by SECYT-UNC Y CICYT-UNLAR.Keywords: Fluoride ? Connexins - Differentiation
Fil: Fontanetti, Pablo Alejandro. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Introducción a la Química y Física Biológicas A; Argentina.
Fil: Interlandi, Victoria. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Fil: Gallará, Raquel Vivian. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Fil: Ponce, Rubén Hugo. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Fil: Centeno, Viviana Andrea. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Química Biológica A; Argentina.
Bioquímica y Biología Molecular (ídem 1.6.3)