Changes on food intake, body weight and salivary amylase synthesis in the submandibular gland of wistar rats treated with bevacizumab and cytostatics / Cambios en la ingesta de alimentos, peso corporal y síntesis de amilasa salival en la glándula submandibular de ratas wistar tratadas con bevacizumab y citostáticos

Background: Bevacizumab together with 5-fluorouracil and oxaliplatin inhibit microvascular growth of tumor blood vessels and tumor proliferation. Few reports state the effect of these therapeutic schemes on salivary glands. Materials and Methods: Food consumption, body weight and salivary amylase activity were assessed in the submandibular gland of rats. Adult male Wistar rats, of three months old with 350/400 grams body weight, under 12-hour light/dark cycles respectively, were divided into the following experimental groups: G1) Control group, G2) 5-Fluorouracil and leucovorin calcium treated group, G3) Bevacizumab treated group, G4) Oxaliplatin treated group, G5) Bevacizumab, oxaliplatin, 5-fluorouracil and leucovorin calcium treated group and G6) Drug-free paired feeding treated group. Assessment of treatment effect was performed by one-way ANOVA. A value of p<0.05 was set for statistical significance. Results: Salivary amylase activity in gland homogenate was G1: 137.9 ± 4.64, G2: 60.95±4.64, G3: 120.93 ± 4.96, G4: 26.17 ±4.64, G5: 10.77 ±4.64 and G6: 82.87 ±4.64 U/mg protein (mean ± S.D.) Amylase activity in the G1 group was higher relative to the other experimental groups p<0.0001. Conclusions: The drugs 5-fluorouracil and oxaliplatin altered salivary amylase activity by serous granules of the submandibular gland interpreted as a mechanism of impaired acinar function. Bevacizumab administered in isolation did not alter salivary amylase activity compared to the control group. While the lower intake of the matched feeding group affected salivary amylase activity compared to the control group, the effect was significantly greater in animals treated with the oncology drugs used in the present animal model.

Antecedentes: Bevacizumab, junto con 5-fluorouracilo y oxaliplatino, inhiben el crecimiento microvascular de los vasos sanguíneos tumorales y la proliferación tumoral. Pocos reportes establecen el efecto de estos esquemas terapéuticos sobre las glándulas salivales. Materiales y Métodos: Se evaluaron el consumo de alimentos, el peso corporal y la actividad de amilasa salival en la glándula submandibular de ratas Wistar macho adultas, de tres meses de edad con 350/400 gramos de peso corporal, bajo ciclos de luz/oscuridad de 12 horas respectivamente, se dividieron en los siguientes grupos experimentales: G1) Grupo control, G2) Grupo tratado con 5-Fluorouracilo y Leucovorina cálcica. , G3) Grupo tratado con bevacizumab, G4) Grupo tratado con oxaliplatino, G5) Grupo tratado con bevacizumab, oxaliplatino, 5-fluorouracilo y leucovorina cálcica y G6) Grupo tratado con alimentación emparejada sin fármacos. La evaluación del efecto del tratamiento se realizó mediante ANOVA unidireccional. Se estableció un valor de p<0,05 para significación estadística. Resultado: La actividad de amilasa salival en homogeneizado de glándula fue G1: 137,9 ± 4,64, G2: 60,95 ± 4,64, G3: 120,93 ± 4,96, G4: 26,17 ± 4,64, G5: 10,77 ± 4,64 y G6: 82,87 ± 4,64 U/mg de proteína (media ± S.E.). La actividad de amilasa en el grupo G1 fue mayor en relación con los otros grupos experimentales p<0,0001. Conclusión: Los fármacos 5-fluorouracilo y oxaliplatino alteraron la actividad de la amilasa salival mediante gránulos serosos de la glándula submandibular interpretados como un mecanismo de deterioro de la función acinar. Bevacizumab administrado de forma aislada no alteró la actividad de la amilasa salival en comparación con el grupo de control. Mientras que la menor ingesta del grupo de alimentación combinada afectó la actividad de la amilasa salival en comparación con el grupo de control, el efecto fue significativamente mayor en los animales tratados con los medicamentos oncológicos utilizados en el grupo. modelo animal actual.

Variaciones morfológicas de la glándula submandibular en ratas obesas por acción de glutamato monosódico / Morphological variations of the submandibular gland in obese rats by the action of monosodium glutamate

Este estudio tuvo como objetivo demostrar la existencia de variaciones morfológicas en el tejido conectivo de la glándula submandibular de ratas obesas expuestas a glutamato monosódico (GMS). Se utilizaron 12 ratas Sprague Dawley machos recién nacidas (6 ratas para el grupo 1, control; 6 ratas para el grupo 2 (GMS), 4 mg/g de glutamato monosódico de peso (5 dosis) mantenidas por 16 semanas respectivamente con una dieta y agua ad libitum. En el estudio se realizó un análisis estereológico e histológico, demostrándose una variación en el tejido conectivo presentando una disminución del volúmen glandular, mayor fibrosis, y disminución de adipocitos a nivel periférico siendo reemplazado por tejido rico en colágeno. Los vasos sanguíneos observados a nivel estereológico no presentan mayores cambios en cuanto a volumen, superficie y área.

SUMMARY: This study aims to demonstrate the existence of morphological variations in the connective tissue of the submandibular gland of obese rats exposed to MSG. Twelve male newborn Sprague Dawley rats were used (6 rats for group 1, control; 6 rats for group 2 (MSG), 4 mg/g of monosodium glutamate of weight (5 doses) maintained for 16 weeks respectively with a diet and water ad libitum. In the study, a stereological and histological analysis was carried out, demonstrating a variation in the connective tissue, presenting a decrease in the glandular volume, greater fibrosis, and a decrease in adipocytes at the peripheral level, being replaced by tissue rich in collagen. Blood cells observed at the stereological level do not present major changes in terms of volume, surface and area, but in the histological study greater vascularization is observed.

Functional impairment in submandibular gland of rats induced by 5-fluorouracil and calcium leucovorin

One of the main clinical problems during chemotherapy is the occurrence of severe systemic toxicities, including those related to the stomatognathic system, which contribute to reducing the patient's quality of life. The most frequent oral complications are mucositis, dysgeusia, inflammation, gingival bleeding and decreased salivary flow or hyposalivation, a factor that predisposes to xerostomia, and other local complications that alter the homeostasis of the system. The purpose of this study was to evaluate the functional activity of salivary glands in Wistar rats subject to chemotherapy by measuring salivary flow, glycogen levels and glandular tissue response to autonomic nervous system agonists. Five experimental groups were used: 1) Control group fed "ad libitum"; 2) 5-fluorouracil (20mg/ kg body weight); 3) Calcium leucovorin (10 mg/kg body weight); 4) 5-fluorouracil + calcium leucovorin (20 and 10 mg / kg, respectively) by intraperitoneal injection for five consecutive days and 5) control with paired diet. Groups 1 and 5 did not receive drugs. Treatment with fluorouracil + leucovorin produced an increase in stimulated salivary flow and a higher response to increasing doses of beta agonists compared to other experimental groups. In both groups treated with cytostatic drugs, blocking of glycogen consumption at the end of the experimental period was observed. Our work suggests that salivary secretion may be affected by a dual mechanism: the first would be toxicity induced by 5-FU, which would cause depression of the process of glucose utilization. The second mechanism would affect the sympathetic autonomic reflex arc. In this instance, the synergistic action of 5-FU + LV would have a negative effect on the nerve activity with a reduction of salivary secretion. This would explain the hyposalivation, cited by several authors in patients undergoing the 5-FU+LV scheme in the treatment of colon carcinoma.

Uno de los principales problemas clinicos durante la quimioterapia es la aparicion de graves efectos toxicos sistemicos, incluidos los relacionados con el sistema estomatognatico, que contribuyen a la reduccion de la calidad de vida del paciente. Las complicaciones orales mas frecuentes son la mucositis, disgeusia, inflamacion, sangrado gingival y la disminucion del flujo salival o hiposalivacion, un factor que predispone a la xerostomia, y otras complicaciones locales que alteran la homeostasis del sistema. El objetivo de este estudio fue evaluar la actividad funcional de las glandulas salivales de ratas Wistar sometidas a quimioterapia, a traves de la medicion del flujo salival, los niveles de glucogeno y la respuesta del tejido glandular a agonistas del sistema nervioso autonomo. Se utilizaron cinco grupos experimentales: 1) Control con alimentacion "ad libitum"; 2) 5 - fluorouracilo (20 mg / kg de peso corporal); 3) Leucovorina calcica (10 mg/ kg de peso corporal); 4) 5 - fluorouracilo + leucovorina calcica (20 y 10 mg / kg, respectivamente) por via intraperitoneal durante cinco dias consecutivos, y 5) control con dieta apareada. Grupos 1 y 5 no recibieron drogas. El tratamiento con 5 - fluorouracilo + leucovorina produjo un aumento de flujo salival estimulado y una mayor respuesta a dosis crecientes de agonistas beta en comparacion con otros grupos experimentales. En ambos grupos tratados con citostaticos, se observo bloqueo del consumo de glucogeno al final del periodo. Nuestro trabajo sugiere que la secrecion salival puede estar afectada por un doble mecanismo: el primero seria la toxicidad inducida por 5-FU que causaria depresion del proceso de utilizacion de la glucosa. El segundo mecanismo afectaria el arco reflejo autonomo simpatico. En este caso, la accion sinergica de ambos farmacos de 5-FU + LV repercutiria negativamente sobre la actividad nerviosa con una reduccion de la secrecion salival. Esto explicaria la hiposalivacion citada por varios autores en pacientes sometidos al esquema 5-FU + LV en el tratamiento del carcinoma colorrectal.

Effect of acute administration of isoproterenol on submandibular salivary gland of female rat.

The functions of salivary glands are under the regulation of both sympathetic as well as parasympathetic nerve fibers. Further, it has also been demonstrated that chronic administration of a beta-adrenergic agonist isoproterenol (IPR) results in hypertrophy and hyperplasia of submandibular gland [Schneyer C A, Am J Physiol, 203 (1962) 232]. Specific purpose of the present attempt was to look for metabolic responses of submandibular gland of oestrous female rats at very short intervals after 10 min of administration of 5, 10 and 15 micrograms of IPR to females in oestrous condition; pharmacological action and clearance time being only 8 min. The results indicated significant reduction in case of enzymic activities of phosphorylase, total ATPase and Na(+)-K+ ATPase. Cyclic AMP-specific phosphodiesterase and succinate dehydrogenase activities were suppressed only with 5 micrograms dose, but with rising dose levels the effect was not so apparent. Protein content of the gland was reduced slightly by administration of IPR. Hence, it became clear that submandibular gland responds rapidly to IPR administration. Implications of these observations are discussed.

Long- term effect of melatonin on submandibular salivary glands in old rats

The effect of melatonin on the submandibular salivary glands of old rats was studied using 20 control and 20 experimental rats which had received melatonin daily for 5 months. The glands were first weighed and then processed for light and electron microscopy. The glands of the melatonin rats were significantly heavier than the controls. With light microscopy, the control group showed a loss of normal architecture of the acini and multiple degenerative changes whereas in the melatonin group the acini had clear architecture and few degenerative changes. With electron microscopy, the control group again showed degenerative changes and little cellular activity whereas the melatonin group had features which indicated increased cellular activity

Transporte eletrolítico pela glândula submandibular do cäo: açäo da furosemida / Electrolytic transport by the dog submandibular gland: furosemide action

A açäo da furosemida sobre a reabsorçäo de sódio pelos ductos da glândula submandibular do cäo foi estudada com a finalidade de esclarecer alguns mecanismos da secreçäo de eletrólitos pela saliva. Foram utilizados 18 animais que, depois de anestesiados com Tionembutal intravenoso, tiveram dissecados o nervo corda do tímpano e o ducto excretor da glândula, sendo este posteriormente canulado. O nervo foi estimulado eletricamente e amostras de saliva foram recolhidas antes e após a injeçäo intravenosa de furosemida, determinando-se seu conteúdo em sódio por fotometria de chama. A açäo da furosemida era evidenciada através de sua potente açäo diurética. Os fluxos salivares por minuto eram calculados, bem como as quantidades totais de sódio reabsorvido pelos ductos e excretado pela saliva acinosa, considerando que esta tem a mesma composiçäo eletrolítica que o plasma e näo existe reabsorçäo de água ao longo dos ductos. Estes experimentos mostraram que houve uma acentuada diminuiçäo do fluxo salivar e uma diminuiçäo ainda maior do sódio reabsorvido, sugerindo que isto ocorra por uma açäo direta da droga sobre os mecanismos de transporte iôntico. A diminuiçäo do fluxo salivar é conseqüência da açäo sobre o transporte iôntico acinoso, açäo esta que é provavelmente diferente daquela que ocorre sobre o mesmo transporte nos ductos. Näo se conseguiu, entretanto, qualquer evidência que pudesse indicar qual das estruturas do adenômero seria mais sensível à açäo da furosemida