Chronic Exposure to Fluoride During Gestation and Lactation Increases Mandibular Bone Volume of Suckling Rats.

We aimed to investigate the effect of maternal exposure to NaF on mandibular bone microarchitecture and phosphocalcic plasma parameters of the offspring. For this purpose, 10-, 15-, and 21-day-old pups (n = 6-8 per group) from two groups of mothers, control and NaF 50mg/L treated dams, were used. Plasma calcium (Ca) and phosphorus (P) levels and alkaline phosphatase activity (ALP) were measured. Fluoride concentration (F-) in bone and in stomach content was measured using potentiometry after isothermal distillation. Morphometric, histological, and histomorphometric analyses of the jaw bones were performed. Plasma Ca and P levels and ALP activity increased in 10-day and decreased in 21-day-old pups from NaF-treated mothers. Fluoride concentration in stomach content samples of 15- and 21-day-old nursing pups from mothers exposed to NaF in their drinking water was higher compared to that observed in control dam offspring. Mandibular F- content was higher in 21-day-old pups born to F--exposed dams compared to those observed in age-matched control pups. Mandibular area increased in 21-day-old pups born to treated mothers as compared to controls. Mandibular bone volume BV/TV (%) was higher in offspring from NaF-exposed dams than in controls at all the studied times. The increase in bone volume after exposure to F- was concomitant with the increase in trabecular thickness and the decrease in trabecular separation. Altogether, our results showed that exposure to NaF during gestation and lactation increased mandibular area and bone volume of pups, with concomitant changes in phosphocalcic parameters associated with the bone modeling process.

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 (20 mg/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.

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.

Fluorosis endémica em zonas rurales del norte y noroeste de la Provincia de Córdoba, Argentina / Endemic fluorosis in northern and northwestern rural areas in the province of Cordoba, Argentina

En zonas del norte (ZN) y noroeste (ZNO) cordobés se estudió la prevalencia de fluorosis dental. En agua de consumo se determinó la concentración de Fluoruro (F-).En individuos de 5 a 14 años se evaluó la ingesta total diariade F-, concentración de F- en saliva y el índice de fluorosis dental. El agua presentó concentración de F- excesiva (ZN: 1,35 a 7,0 mg/l; ZNO: 1.7 a 3,4 mg/l). La ingesta diaria deF- duplicó la recomendada por la OMS (1,68 mg/día). El Fensaliva basal fue de 0,11 ± 0,03 mg/l (ZN) y 0,02 ± 0,001 mg/l (ZNO). La fluorosis dental en todas las superficies dentales permanentes fue del 75,6% (ZN) y 86.7% (ZNO)y en dientes maxilares anteriores del 87,7% (ZN) y 77,8% (ZNO). En el segundo molar primario fue del 22,2% (ZN) y 32,5% (ZNO). Se establece que ambas zonas son áreas de fluorosis endémica.

The prevalence of dental fluorosis was studied in northern(N) and northwestern (NW) areas of the province of Cordoba,Argentina. Fluoride (F-) concentration in drinking water wasdetermined. Daily total intake of F-, salivary F- concentrationand dental fluorosis index were evaluated in individuals from 5 to 14 years old. F- concentration in water was excessive (N: 1.35 to 7.0 mg/l; NW: 1.7to 3.4 mg/l). Daily intake of F- doubled the intake recommended by WHO (1.68 mg/day).

Environmental light conditions alter gene expression of rat catecholamine biosynthetic enzymes and Neuropeptide Y: differential effect in superior cervical ganglia and adrenal gland.

The hypothalamic suprachiasmatic nuclei (SCN) comprise the main site in the brain involved in the control of the homeostatic mechanism which respond to environmental daily light changes. The sympathetic nervous system and hypothalamic releasing or inhibiting factors mediate the SCN control of a number of peripheral organs and tissues. In this work we analyzed the involvement of two environmental light conditions, constant light (LL) and constant dark (DD) for 20 days, on the expression of mRNAs for catecholamines biosynthetic enzymes and neuropeptide Y (NPY) genes in rat superior cervical ganglia (SCG) and adrenal gland. The results of Northern blot analysis show that LL exposure reduces mRNA levels for tyrosine hydroxylase (TH) the rate limiting catecholamine biosynthetic enzyme and also of dopamine beta-hydroxylase (DBH) as well as for NPY in SCG to about half the levels in control animals. In contrast, exposure of the rats to DD did not elicit any change in the SCG. In the adrenal gland, both, LL and DD conditions increased the TH, DBH as well as phenylethanolamine N-methyltransferase (PNMT) mRNA levels. Under the same conditions, adrenal NPY mRNA levels were decreased by either LL or DD. The results show, for the first time, that prolonged changes in environmental light can alter the gene expression of catecholamine biosynthetic enzymes and of NPY. There was differential response in SCG and adrenal gland.