RESUMO
This study presents a comprehensive characterization of the viscoelastic and structural properties of bovine submaxillary mucin (BSM), which is widely used as a commercial source to conduct mucus-related research. We conducted concentration studies of BSM and examined the effects of various additives, NaCl, CaCl2, MgCl2, lysozyme, and DNA, on its rheological behavior. A notable connection between BSM concentration and viscoelastic properties was observed, particularly under varying ionic conditions. The rheological spectra could be well described by a fractional Kelvin-Voigt model with a minimum of model parameters. A detailed proteomics analysis provided insight into the protein, especially mucin composition within BSM, showing MUC19 as the main component. Cryo-scanning electron microscopy enabled the visualization of the porous BSM network structure. These investigations give us a more profound comprehension of the BSM properties, especially those pertaining to viscoelasticity, and how they are influenced by concentration and environmental conditions, aspects relevant to the field of mucus research.
Assuntos
Hidrogéis , Mucinas , Animais , Bovinos , Mucinas/química , Hidrogéis/química , Viscosidade , Elasticidade , Reologia , Glândula Submandibular/química , Glândula Submandibular/metabolismoRESUMO
Studying salivary gland mucins is important for elucidating the pathogenesis of salivary gland diseases, including tumors and xerostomia, and developing diagnostic methods for them. Classic methods for isolating mucins from salivary glands require sacrificing several animals to obtain sufficient quantities of mucin and are time-consuming. Supported molecular matrix electrophoresis (SMME) was used to characterize mucins and their glycans. With this method, mucins can be analyzed within 2 days using less than 100 mg of tissue and without using expensive equipment, such as an ultracentrifuge. This chapter describes a method for preparing mucin solutions for SMME analysis of salivary gland mucins.
Assuntos
Mucinas , Glândula Submandibular , Animais , Glândula Submandibular/química , Glândulas Salivares , Eletroforese/métodos , PolissacarídeosRESUMO
Abstract Objective This study aimed to demonstrate the immunohistochemical changes associated with MMP-2 and type 1 collagen separately for the first time in the major salivary glands (the parotid, submaxillary, and sublingual glands) that occur with aging in mice. Material and Methods Fourteen Balb/c white mice (50-80 g) were used in this study. The animals were divided into two equal groups. Group I consisted of young animals (2-month-old) (n=7) and Group II consisted of older animals (18-month-old) (n=7). After routine histological follow-ups, Hematoxylin-eosin (H&E), Masson's Trichrome staining and immunohistochemical staining was performed for type I collagen and MMP-2. Results We observed that there were age-related decreases in the number of acinar cells, increase in eosinophilic zymogen granules in cells, collagen accumulation in fibrotic areas and dilatation in interlobular ducts. Also, while type I collagen and MMP-2 immunoreactivity were moderate in the salivary glands of the young mice, they were high in the salivary glands of the old mice (p=0.001). In the H-score assessment, MMP-2 immunoreactivity was lower at a significant level in young mice than in old mice (p=0.001). Conclusions This study showed that anatomical, physiological and morphological abnormalities occur in all three major salivary glands as a natural consequence of aging.
Assuntos
Animais , Feminino , Glândula Parótida/química , Glândula Sublingual/química , Glândula Submandibular/química , Metaloproteinase 2 da Matriz/análise , Colágeno Tipo I/análise , Glândula Parótida/fisiopatologia , Glândula Parótida/patologia , Valores de Referência , Glândula Sublingual/fisiopatologia , Glândula Sublingual/patologia , Glândula Submandibular/fisiopatologia , Glândula Submandibular/patologia , Imuno-Histoquímica , Fatores Etários , Camundongos Endogâmicos BALB CRESUMO
Saliva is the first barrier to entry of bacteria and viruses into the body. The submandibular glands (SMG) contribute to the maintenance of oral health and regulation of immune/ inflam matory responses. Previous studies suggest that transforming growth factor beta 1 (TGFB1) may contribute to salivary gland fibrosis but the expression of the TGFB1 system in the SMG has not been elucidated. Thus, the aim of this study was to analyze in rat SMG the immunolocalization of TGFB1 and its specific receptors ALK5 (profibrotic) and ALK1 (proproliferative) and the coreceptor endoglin (EDG) in a bilateral experimental periodontitis (EP) model (cotton thread ligature around the neck of the first lower molars) for 1 and 6 weeks. Fixed SMG were embedded in paraffin and serially cut for routine hematoxylin-eosin staining for histological analysis or immunohistochemical techniques by diaminobenzidine detection. SMG histology from animals with EP showed timedependent structural changes involving marked reduction in the height of the contoured ducts, cell destruction, loss of secretory granules, periductal congestion and excess connective tissue surrounding these ducts indicative of a fibrotic process, compared to control SMG. TGFB1, ALK5 and ALK1 receptors and the coreceptor EDG were mainly immunolocalized in ductal cells and in the fibrotic areas in EP groups. The expression of the profibrotic ALK5 receptor was increased in areas of fibrosis in SMG of animals with EP. In SMG of rats with EP, the localization of the TGFB1 specific receptors in the ducts and cells from fibrotic areas, due to the expression of TGFB1 in the surrounding areas, might indicate paracrine and autocrine actions exerted by TGFB1 via its specific receptors. The results of this study suggest that TGFB1 promotes fibrosis, inducing cell proliferation via ALK1 and EDG receptors and stimulates fibrosis relatedprocesses via ALK5 receptor, which could lead to abnormal secretor activity of the SMG during periodontal disease.
La saliva es la primera barrera para la entrada de bacterias y virus en el cuerpo. Las glándulas submandibulares (GSM) contribuyen al mantenimiento de la salud oral y a la regulación de las respuestas inmunoinflamatorias. Estudios previos sugieren que el factor de crecimiento transformante beta 1 (TGFB1) puede contribuir a la fibrosis de las glándulas salivales, pero la expresión y localización del sistema TGFB1 en las GSM no ha sido dilucidada. El objetivo del presente trabajo fue analizar por inmunohistoquímica en las GSM de ratas la expresión de TGFB1 y sus receptores específicos ALK5 (profibrótico) y ALK1 (proproliferativo) y el coreceptor endoglina (EDG) en un modelo de periodontitis bilateral experimental (PE) (hilo de algodón alrededor del cuello de los primeros molares inferiores) durante 1 y 6 semanas. Las GSM fueron fijadas y embebidas en parafina para realizar cortes seriados los cuales se tiñeron con hematoxilinaeosina para analizar la histología o se procesaron para realizar la técnica de inmunohistoquímica mediante detección con diaminobenzidine. La histología de las GSM de animales con PE reveló cambios estructurales tiempo dependientes, con una marcada reducción de la altura de los conductos, destrucción celular, pérdida de gránulos secretores, congestión periductal y exceso de tejido conectivo que rodea los conductos, indicando un proceso de fibrosis respecto de las GSM de animales control. TGFB1, ALK5 y ALK1 y el coreceptor EDG fueron principalmente inmunolocalizados en las células que forman los ductos y en las áreas de fibrosis en los grupos con PE. La expresión del receptor profibrótico ALK5 se incrementó en las áreas de fibrosis en GSM de animales con PE. En GSM de ratas con PE, la localización de los receptores específicos de TGFB1 en las células de los conductos y áreas de fibrosis, junto con la expresión de TGFB1 en las áreas circundantes, podría indicar acciones paracrinas y autocrinas ejercidas por TGFB1 a través de sus receptores específicos. Los resultados de este estudio sugieren que TGFB1 podría inducir un proceso de fibrosis promoviendo la proliferación celular a través de los receptores ALK1 y EDG, y favoreciendo procesos relacionados con la fibrosis a través de su receptor ALK5, lo que conduciría a una actividad secretora anormal de la GSM durante la enfermedad periodontal.
Assuntos
Animais , Masculino , Ratos , Glândula Submandibular/patologia , Fator de Crescimento Transformador beta1/biossíntese , Periodontite/complicações , Glândula Submandibular/química , Fibrose/etiologia , Imuno-Histoquímica , Ratos Wistar , Fator de Crescimento Transformador beta1/análiseRESUMO
Rats experimentally infected with Trypanosoma cruzi Y strain exhibited hypertrophy of the submandibular gland at 18 days after infection.SDS-PAGE of infected rats saliva revealed the presence of an additional band with an apparent molecular weight of about 13KDa. Electrophoresis of protein salivaand immunochemical analysis with antibody against rat cystatin S confirmed that the protein was identical to that induced by beta adrenergic stimulation
Assuntos
Animais , Masculino , Ratos , Cistatinas/análise , Doença de Chagas/patologia , Glândula Submandibular/patologia , Western Blotting , Cistatinas/biossíntese , Glândula Submandibular/química , Hipertrofia , Ratos Endogâmicos , Saliva/químicaRESUMO
O objetivo desta pesquisa foi de verificar, através de quantificaçöes esteriológicas ao microscópio óptico, a participaçäo dos processos hiperplásicos e hipertrófico no crescimento do comportamento dos ácinos de glândulas submandibulares de ratos machos, induzido por injeçöes diárias de cloridrato de isoproterenol por 14 dias. A análise dos resultados obtidos mostrou que: a) a massa glandular aumentou 135,8 por cento entre 0 a 14 dias, sendo que entre 0 a 3 dias foi observada a maior velocidade de crescimento; b) a densidade de volume, ou seja, o percentual de volume glandular ocupada pelos ácinos aumentou nos períodos de 0 a 3 e 5 a 7 dias, respectivamente, de 1,33 e 1,10 vezes; c) o volume absoluto desse comportamento passou de 131,9 milímetros cúbicos aos 0 dias para 522,5 milímetros cúbicos aos 14 dias de tratamento, o que representou um aumento de 296,1 por cento; d) o volume celular médio exibiu um soberbo crescimento de 585,4 por cento após 14 dias de tratamento, sendo que entre 0 a 3 e 5 a 7 dias, os aumentos foram, respectivamente, 286,3 por cento e 45 por cento; e) o número absoluto ora apresentados, mostraram que o crescimento do volume total do comportamento acinar de glândulas submandibulares de ratos induzidos pelo isoproterenol, ocorre essencialmente por um mecanismo hipertrófico