RESUMO
The etiology of midface retrusion remains largely unclear. We hypothesized that the cranial base synchondroses play a key role in the development of the craniofacial skeleton in the Sandhoff mouse model. We observed that developmental abnormalities of the cranial base synchondroses involving proliferative chondrocytes are important in craniofacial growth and development. Neonatal restitution of beta-hexosaminidase in mutant mice by gene therapy successfully ameliorated the attendant skeletal defects and restored craniofacial morphology in vivo, suggesting this as a critical temporal window in craniofacial development. Analysis of our data implicates parathyroid-related peptide (PTHrP) and cyclo-oxygenase-2 (COX-2) as possible factors underlying the development of the aforementioned skeletal defects. Hence, timely restitution of a genetic deficiency or, alternatively, the restoration of PTHrP or cyclo-oxygenase activity by the administration of PTH and/or non-steroidal anti-inflammatory drugs or COX-2 selective inhibitors to affected individuals may prove beneficial in the management of midface retrusion.
Assuntos
Ossos Faciais/anormalidades , Desenvolvimento Maxilofacial/fisiologia , Doença de Sandhoff/genética , Base do Crânio/crescimento & desenvolvimento , beta-N-Acetil-Hexosaminidases/fisiologia , Animais , Cefalometria , Condrócitos/patologia , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Terapia Genética , Lâmina de Crescimento/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Proteína Relacionada ao Hormônio Paratireóideo/deficiência , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Doença de Sandhoff/terapia , beta-N-Acetil-Hexosaminidases/deficiência , beta-N-Acetil-Hexosaminidases/genéticaRESUMO
Gene therapy is emerging as a novel treatment method for the management of temporomandibular joint disorders. The aim of this investigation was to study the effects of lentiviral vectors on the temporomandibular joint. Consequently, we injected into the articular joint space a defective feline immunodeficiency virus capable of infecting dividing as well as terminally differentiated cells with the reporter gene lacZ, the expression of which was studied by means of PCR, X-gal histochemistry, and beta-galactosidase immunocytochemistry. Our results showed successful transduction of hard and soft tissues of the temporomandibular joint. Interestingly, a subset of primary sensory neurons of the ipsilateral trigeminal ganglion also stained positive for the reporter gene, presumably following uptake of the lentiviral vector by peripheral nerve fibers and retrograde transport to the nucleus. These findings suggest that lentiviral vectors can potentially serve as a platform for the transfer of anti-nociceptive genes for the management of temporomandibular joint pain.
