Efeito de testosterona na proliferação celular e de TGF-[beta]1, IL-6 e INF-[gama] na expressão e produção de colageno tipo I, Hsp47 e metaloproteinases de matriz em fibroblastos de gengiva normal e de fibromatose gengival hereditaria

Orientador: Ricardo Della ColettaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Fibromatose Ggengival Hereditária (FGH) representa uma condição oral incomum, caracterizada por aumento gengival fibrótico e generalizado. Para elucidar algumas características regulatórias que resultam nesta condição, linhagens celulares de fibroblastos de pacientes de uma mesma família com FGH foram isolados e analisados em relação ao efeito de diidrotestosterona (DHT) na proliferação celular e de TGF-ßl, IL-6 e INF-? na expressão e produção de colágeno tipo I, Hsp47, MMP-I e MMP-2. Adicionalmente, analisamos o efeito de DHT na produção de IL-6 e determinamos os níveis de expressão de receptores de andrógenos em fibroblastos de GN e de FGH. Os resultados indicaram que DHT simultaneamente estimulou a proliferação celular e inibiu a produção de IL-6 em fibroblastos de GN e de FGH. A expressão de receptores para andrógenos foi detectada em fibroblastos de GN e de FGH; contudo, a expressão foi maior em fibroblastos de GN. Ensaios de RT-PCR, westem blot, ELISA e enzimografia demonstraram que a expressão e produção de colágeno tipo I e Hsp47 foram significativamente maiores em fibroblastos de FGH comparados a fibroblastos de GN, enquanto a expressão de MMP-I e MMP-2 foram menores em fibroblastos de FGH. A adição de TGF-ßl e IL-6 à fibroblastos de GN e de FGH promoveram um aumento na expressão de colágeno tipo I e Hsp47 e uma diminuição de MMP-I e MMP-2. INF-y reduziu a expressão de colágeno tipo I e Hsp47, apresentando menor efeito na expressão de MMP-I e MMP-2. Estes resultados demostram que DHT coordena a proliferação celular e a produção de IL-6 em fibroblastos de GN e de FGH e que TGF-ßl e IL-6 estimulam a síntese de colágeno e reduzem a atividade proteolítica de fibroblastos de FGH, os quais favorecem o acúmulo de matriz extracelularAbstract: Hereditary Gingival Fibromatosis (HGF) is an uncommon oral condition characterized by a fibrous gingival enlargement. To further elucidate some of the regulatory features resulting in this condition, the culture characteristics of cell lines of gingival fibroblasts derived from patients ofthe some family with HGF were isolated and analyzed on the effect of DHT on proliferation rate and on the effect of TGF-ßl, IL-6 and INF-? on expression and production of type I collagen, Hsp47, MMP-I and MMP-2. Additionally, we analyzed the effect of DHT on IL-6 production and determined the expression levels of androgen receptors in NG and HGF fibroblasts. The results indicated that DHT simultaneously upregulated the cell stimulates proliferation and downregulated the production of IL-6 production by NG and HGF fibroblasts. Androgen receptor levels was identified in both NG and HGF fibroblasts; however, the levels in NG were higher than those observed in HGF. Our results obtained from RT-PCR, Westem blot, ELISA and enzymography assays demonstrated that the expression and production of type I collagen and Hsp47 were significantly higher in fibroblasts from HGF than from NG, whereas MMP- 1 and MMP-2 expression and production were lower in fibroblasts from HGF patients. Addition of TGF-ßl and IL-6 promoted an increase in type I collagen and Hsp47 and decrease in MMP-I and MMP-2 expression. INF-y reduced both type I collagen and Hsp47 expression, whereas had a slight effect on expression of MMP-I and MMP-2. These results show that DHT coordinates the proliferation and production of IL-6 by NG and HGF fibroblasts and that enhanced TGF-ß1 and IL-6 production simultaneously increase the synthesis and reduce the proteolytic activies of HGF fibroblasts, which favor the accumulation of extracellular matrixDoutoradoEstomatologiaDoutor em Estomatopatologi

Study of the sinthesis of Hsp47 and Sec61'alfa' during the events of translacions/translocations of collagen type I in fibroblasts from hereditary gingival fibromatosis

Orientador: Luciano Resende FerreiraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Fibromatose Gengival Hereditária (FGH) representa uma condição oral incomum (1:750.000), caracterizada por um aumento gengival fibrótico generalizado. Manifesta-se como entidade clínica isolada ou como parte de síndromes, produzindo excessiva quantidade de colágeno e outras moléculas da matriz extra-celular. Hsp47 é uma chaperone residente no retículo endoplasmático (RE) que liga especificamente a moléculas de colágeno, enquanto Sec61 a representa uma proteína transmembrânica com ativa participação na condução de cadeias polipeptídicas nascentes para o lúmen do RE. Este trabalho descreve a participação das proteínas Hsp47 e Sec61? em culturas de fibroblastos provenientes de uma única família portadora de FGH e de pacientes com gengiva normal (GN) nos eventos de translação/translocação de colágeno tipo I. Ensaios de Western blot mostraram uma produção aumentada de Hsp47 em fibroblastos de FGH, comparado a fibroblastos de GN em condições de homeostasia e em situações de estresse térmico. Além disso, foi demonstrado produção de Sec61? nas linhagens celulares, FGH e GN, porém sem diferenças nos padrões de produção. A maior produção de Hsp47 pode estar envolvida na proteção da degradação intra reticular de colágeno, podendo ser um dos fatores responsáveis pela fibrose característica desta doença. Embora os mecanismos biológicos responsáveis pela FGH sejam ainda desconhecidos, o conhecimento da participação destas proteínas na regulação da biosíntese de colágeno pode ser importante para o entendimento de condições genéticas, como a FGHAbstract: Study of the sinthesis of Hsp47 and Sec61??during the events of translacions/translocations of collagen type I in fibroblasts from hereditary gingival fibromatosis Hereditary Gingival Fibromatosis (HGF) represents an uncommon oral condition (l :750,000) characterized fibrous gingival enlargement. HGF can manifest as an isolated clinical entity or as part of a syndrome. The gingiva of patients with HGF produce excessive amount of collagen and other extracellular matrix. Hsp47 is an endoplasmic reticulun (ER) resident chaperone which binds specifically to collagen molecules, and Sec61? represents a transmembranous protein with active role in conducting of nascent polypeptide chain into the ER. This study describes the role of Hsp47 and Sec61? during the events of translationltranslocation of collagen type I in fibroblasts from patients with HGF and patients presenting normal gingiva (NG). Western blot assays demonstrated an increased production of Hsp47 in fibroblasts HGF as compared to NG cells under stress and unstressed conditions. In addition, Sec61? was evenly found in both cell types showing no marked variations in quantity in both stressed or unstressed situations. The more increased production of Hsp47 may related to a collagen degradation protective mechanism inside the ER. This can be one of the factors responsible for the fibrous features of HGF. Although the exact biological mechanisms involved in HGF are still unknown, the study of these ER proteins role in regulating collagen biosynthesis may be important for understanding hereditary conditions such as HGFMestradoMestre em Biologia e Patologia Buco-Denta

Pfeiffer Syndrome: Clinical And Genetic Findings In Five Brazilian Families

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Pfeiffer syndrome (PS) is mainly characterized by craniosysnostosis, midface hypoplasia, great toes with partial syndactyly of the digits and broad and medially deviated thumbs. It is caused by allelic mutations in the fibroblast growth factor receptor 1 and 2 (FGFR1 and 2) genes. This study describes the clinical and genetic features of five Brazilian families affected by PS. All patients exhibited the classical phenotypes related to PS. The genetic analysis was able to detect the mutations Cys278Phe, Cys342Arg, and Val359Leu in three of these families. Two mutations were de novo, with one familial. We identified pathogenic mutations in four PS cases in five Brazilian families by PCR sequencing of FGFR1 exon 5 and FGFR2 exons 5, 8, 10, 11, 15, and 16. The clinical and genetic aspects of these families confirm that this syndrome can be clinically variable, with different mutations in the FGFR2 responsible for PS.201E52E58Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Cyclosporin A-induced gingival overgrowth is not associated with myofibroblast transdifferentiation

Cyclosporin A (CyA) induces gingival overgrowth via its stimulatory effects on expression of transforming growth factor-beta1 (TGF-β1) and collagen. It is not known whether CyA has a direct effect on gingival fibroblasts or induces its effect indirectly via stimulation of myofibroblast transdifferentiation. The present study was undertaken to examine the in vivo and in vitro effect of CyA on myofibroblast transdifferentiation. Rats were treated for 60 days with a daily subcutaneous injection of CyA, and the gingival overgrowth tissue was analyzed by immunohistochemistry. In vitro, fibroblasts from normal gingiva (NG) were cultured in the presence of different concentrations of CyA, and subjected to semi-quantitative reverse transcriptase-polymerase chain reaction and western blot. Although CyA treatment stimulated TGF-β1 expression by NG fibroblasts, it lacked to induce expression and production of isoform α of smooth muscle actin (α-SMA), the specific myofibroblast marker. The expression levels of connective tissue growth factor (CTGF), which has been considered a key molecule to promote the transdifferentiation of myofibroblasts via TGF-β1 activation, were unaffected by CyA. Our results demonstrate that CyA-induced gingival overgrowth is not associated with activation of myofibroblast transdifferentiation, since CyA is not capable to increase CTGF expression

Pfeiffer syndrome: clinical and genetic findings in five Brazilian families

Pfeiffer syndrome (PS) is mainly characterized by craniosysnostosis, midface hypoplasia, great toes with partial syndactyly of the digits and broad and medially deviated thumbs. It is caused by allelic mutations in the fibroblast growth factor receptor 1 and 2 (FGFR1 and 2) genes. This study describes the clinical and genetic features of five Brazilian families affected by PS. All patients exhibited the classical phenotypes related to PS. The genetic analysis was able to detect the mutations Cys278Phe, Cys342Arg, and Val359Leu in three of these families. Two mutations were de novo, with one familial. We identified pathogenic mutations in four PS cases in five Brazilian families by PCR sequencing of FGFR1 exon 5 and FGFR2 exons 5, 8, 10, 11, 15, and 16. The clinical and genetic aspects of these families confirm that this syndrome can be clinically variable, with different mutations in the FGFR2 responsible for PS201E52E58CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGsem informaçã

Tuberous sclerosis complex diagnosed from oral lesions

CONTEXT: Tuberous sclerosis complex (TSC) is a genetic disease in the group known as neurocutaneous syndromes, with dominant autosomal inheritance. It is characterized by skin and adnexal lesions and central and peripheral nervous system tumors, with neurological and psychiatric findings. It may affect the heart, kidneys, eyes, face, bones, lungs, stomach and dentition. CASE REPORT: We present the case of a 66-year-old man with dermatological signs that included hypopigmented maculae, confetti-like lesions, shagreen plaque, angiofibromas on nasolabial folds, neck and back, nail dystrophy and periungual fibromas on fingers and toes. An electroencephalogram produced normal results, but magnetic resonance imaging showed a nodular image measuring 1.2 x 1.0 cm close to the Monro foramen, which was similar to cerebral parenchyma and compatible with a subependymal giant-cell astrocytoma. A conservative approach was taken, through control imaging examinations on the lesion for seven years, with absence of any expansive process or neurological symptoms. Abdominal ultrasonography revealed a solid, heterogenic and echogenic mass with a calcified focus, measuring 4.6 x 3.4 cm, in the rightkidney, compatible with angiomyolipoma. The patient was treated by means of complete nephrectomy because of malignant areas seen on histopathological examination and died one month after the procedure. This case report illustrates the importance of oral clinical findings such as dental enamel pits and angiofibromas in making an early diagnosis of TSC, with subsequent screening examinations, treatment and genetic counseling