RESUMEN
INTRODUCTION: Inflammatory cytokines are associated with decreased insulin signal transduction. Moreover, local oral inflammation, such as that accompanying periodontal disease, is associated with insulin resistance and type 2 diabetes mellitus. The aim of this study was to evaluate the effect of periapical lesions (PLs) on insulin signaling and insulin sensitivity in rats. We hypothesized that PLs alter systemic insulin signaling and insulin sensitivity via elevated plasmatic tumor necrosis factor α (TNF-α). METHODS: Wistar rats were divided into control (CN) and PL groups. PLs were induced by exposing pulpal tissue to the oral environment. After 30 days, insulin sensitivity was measured using the insulin tolerance test. After euthanization, maxillae were processed for histopathology. Plasmatic concentrations of tumor necrosis factor α (TNF-α) were determined via the enzyme-linked immunosorbent assay. Insulin signal transduction was evaluated using insulin receptor substrate tyrosine phosphorylation status and serine phosphorylation status in periepididymal white adipose tissue via Western blotting. For insulin signaling and insulin tolerance tests, the analyses performed were analysis of variance followed by the Tukey post hoc test. For TNF-α analysis, the Student's t test was used. In all tests, P < .05 was considered significant. RESULTS: The rats with PLs showed higher plasmatic TNF-α, lower constant rate for glucose disappearance values, and reduced pp185 tyrosine phosphorylation status but no change in serine phosphorylation status in white adipose tissue after insulin stimulation. CONCLUSIONS: PLs can cause alterations to both insulin signaling and insulin sensitivity, probably because of elevation of plasmatic TNF-α. The results from this study emphasize the importance of the prevention of local inflammatory diseases, such as PLs, with regard to the prevention of insulin resistance.
Asunto(s)
Resistencia a la Insulina/fisiología , Insulina/fisiología , Enfermedades Periapicales/fisiopatología , Transducción de Señal/fisiología , Tejido Adiposo Blanco/patología , Animales , Exposición de la Pulpa Dental/complicaciones , Necrosis de la Pulpa Dental/complicaciones , Insulina/sangre , Proteínas Sustrato del Receptor de Insulina/análisis , Leucocitos Mononucleares/patología , Masculino , Neutrófilos/patología , Enfermedades Periapicales/sangre , Fosforilación , Ratas , Ratas Wistar , Receptor de Insulina/análisis , Serina/metabolismo , Factores de Tiempo , Factor de Necrosis Tumoral alfa/sangre , Tirosina/metabolismoRESUMEN
INTRODUCTION: Cardiovascular diseases have been associated with increased risk of endodontic complications. This study evaluated the effects of the antioxidant agent tempol on periapical lesions in rats with doxorubicin-induced cardiomyopathy in comparison with control animals. METHODS: Forty male Wistar rats were divided into 4 groups: (1) naïve rats orally treated with saline solution (10 mL/kg, during 21 days after periapical lesion induction); (2) naïve rats treated with tempol (30 and 50 mg/kg, during 21 days after periapical lesion induction) by oral pathway; (3) rats with doxorubicin-induced cardiomyopathy treated with saline solution by oral route (10 mL/kg, from day 3 to day 10 after initiating treatment with doxorubicin); and (4) rats with doxorubicin-induced cardiomyopathy orally treated with tempol (30 and 50 mg/kg, from day 3 to day 10 after initiating treatment with doxorubicin). Periapical lesions were induced on the first right mandibular molar tooth. After 21 days of apical periodontitis induction, the animals were killed, and the mandibles were collected for radiographic and histologic analysis. RESULTS: The oral administration of tempol (50 mg/kg) was able to significantly prevent the establishment of periapical lesions in either control animals or rats submitted to the model of doxorubicin-induced cardiomyopathy, according to radiographic and histologic evaluation. Nevertheless, the protective effects of tempol were virtually greater in control animals in comparison with doxorubicin-treated rats, as indicated by histologic inflammatory assessment, which might be related to the increased production of free radicals under cardiomyopathy. CONCLUSIONS: We provide novel evidence on the beneficial systemic effects of the antioxidant tempol on apical periodontitis in both control animals and rats with doxorubicin-elicited cardiomyopathy.
Asunto(s)
Antioxidantes/uso terapéutico , Cardiomiopatías/complicaciones , Óxidos N-Cíclicos/uso terapéutico , Periodontitis Periapical/prevención & control , Animales , Antibióticos Antineoplásicos/efectos adversos , Cardiomiopatías/inducido químicamente , Catalasa/análisis , Exposición de la Pulpa Dental/complicaciones , Modelos Animales de Enfermedad , Doxorrubicina/efectos adversos , Procesamiento de Imagen Asistido por Computador , Hígado/enzimología , Masculino , Diente Molar/patología , Miocardio/enzimología , Estrés Oxidativo , Radiografía Dental Digital , Ratas , Ratas Wistar , Marcadores de SpinRESUMEN
OBJECTIVE: The objective of this study was to determine the expression of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) during apical periodontitis development. METHODS: Using an experimental design of induced periapical lesions in rats and immunohistochemistry assay as investigative tool, the MMP-2 and MMP-9 expression and distribution were evaluated at 3, 7, 14, 21, 30, 60 and 90 days after coronary access and pulp exposure of the first left mandibular molar to the oral environment. Two blind observers scored the immunoreactivity. A semi-quantitative analysis was performed. RESULTS: Except at day 3, MMP-2 and MMP-9 immunostaining was observed in all experimental periods. The MMP-2 (p=0.004) and MMP-9 (p=0.005) immunostaining was higher in the period between 7 and 21 days. They were mainly observed in cells surrounding the apical foramen and adjacent periapical areas. Cells into the hypercementosis areas were strongly stained while both osteoblasts and osteoclasts presented discrete staining along of this study. No staining was observed on epithelial walls. At 30, 60 and 90 days, the subjacent connective tissue presented intense MMP-2 and MMP-9 immunostaining in mononuclear cells (suggestive of fibroblasts, macrophages, infiltrating neutrophils and lymphocytes). CONCLUSION: The results observed in this study suggest that MMP-2 and MMP-9 play a critical role in the development of inflammatory periapical lesions, probably involved in the extracellular matrix (ECM) degradation during the initial phase of the lesion development.
Asunto(s)
Metaloproteinasa 2 de la Matriz/análisis , Metaloproteinasa 9 de la Matriz/análisis , Periodontitis Periapical/enzimología , Animales , Tejido Conectivo/enzimología , Tejido Conectivo/patología , Exposición de la Pulpa Dental/complicaciones , Modelos Animales de Enfermedad , Matriz Extracelular/enzimología , Matriz Extracelular/patología , Fibroblastos/enzimología , Fibroblastos/patología , Hipercementosis/enzimología , Hipercementosis/patología , Inmunohistoquímica , Linfocitos/enzimología , Linfocitos/patología , Macrófagos/enzimología , Macrófagos/patología , Masculino , Neutrófilos/enzimología , Neutrófilos/patología , Osteoblastos/enzimología , Osteoblastos/patología , Osteoclastos/enzimología , Osteoclastos/patología , Periodontitis Periapical/etiología , Periodontitis Periapical/patología , Tejido Periapical/enzimología , Tejido Periapical/patología , Distribución Aleatoria , Ratas , Ratas Wistar , Factores de Tiempo , Ápice del Diente/enzimología , Ápice del Diente/patologíaRESUMEN
Traumatic dental injuries are relatively frequent accidents that typically involve teeth in the maxillary anterior segment. The emergency treatment and the clinical decisions must be efficiently made at the time of injury, and there is a need for long-term follow-up because of the high incidence of complications. The aim of this article was to present the emergency and rehabilitation treatments of a multiple dentoalveolar trauma in the permanent dentition involving different extensions of enamel-dentin crown fracture, pulp exposure, and the avulsion of a canine. The treatment outcomes are reported up to the 4-year follow-up, and the clinical approaches and their rationale are discussed.
Asunto(s)
Fracturas Mandibulares/complicaciones , Avulsión de Diente/complicaciones , Fracturas de los Dientes/complicaciones , Accidentes de Tránsito , Adulto , Diente Canino/lesiones , Exposición de la Pulpa Dental/complicaciones , Exposición de la Pulpa Dental/terapia , Tratamiento de Urgencia , Estudios de Seguimiento , Humanos , Incisivo/lesiones , Masculino , Tratamiento del Conducto Radicular , Resorción Radicular/etiología , Avulsión de Diente/terapia , Corona del Diente/lesiones , Reimplante Dental/efectos adversosRESUMEN
The purpose of this study was to investigate and to compare radiographically the development of periapical lesions in the lower left first molar of normal rats, sialoadenectomised rats and sialoadenectomised-immunosuppressed rats. Sixty male Wistar rats, weighing from 170 to 200 g were utilized. The animals were divided equally into three groups: group I--20 normal rats; group II--20 sialoadenectomised rats; and group III--20 sialoadenectomised-immunosuppressed rats. Groups II and III were sialoadenectomized using the modified Cheyne technique. After 2 weeks, group III was submitted to a immunosuppression regimen by daily subcutaneous cyclosporin A injection (10 mg/kg body weight). After 1 week of immunosuppression for this group, the pulps of all the animals (group I, II and III) were exposed to the oral cavity, to produce apical periodontitis. Five animals of each group were killed 7, 14, 21 and 28 days after pulpal exposure. Their mandibles were surgically removed and radiographically analysed. The lesions were measured using 'Global Lab Image' software. The results showed predictable growth of the lesions during the experimental period. No significant difference was observed between the groups. It was concluded that possible changes in the oral flora and in the host immune response due to xerostomia associated or not to the immunosuppression did not alter the development of the periapical lesions in rats.