Effects of ovariectomy, estrogen and soy isoflavones in rats submandibular glands / Efeitos da ovariectomia, estrógeno e isoflavonas da soja em glândulas sumandibulares de ratos

Objetivo: Diminuição das células granulares do túbulo contorcido granular e dos ácinos ocorre nas glândulas submandibulares de ratas fêmeas ovariectomizadas, enquanto que nas ratas submetidas a reposição hormonal e fitoterapia com isoflavona da soja, este efeito é revertido. Este estudo tem como objetivo elucidar os mecanismos pelo qual estas alterações ocorrem. Material e Métodos: 84 ratas foram ovariectomizadas e 21 foram sham-operatadas. As ratas ovariectomizadas foram aleatoriamente subdivididas e receberam administração oral dos seguintes medicamentos: 17 ß-estradiol (OVX-E; n=21), 15 mg/ kg/day do extrato de isoflavona da soja (OVX-I; n=21), 17 ß-estradiol + extrato de isoflavona da soja (OVX-A; n=21); e água como placebo (OVX; n=21). As ratas foram eutanasiadas 3, 5 e 8 semanas após a ovariectomia. As glândulas submandibulares foram submetidas a análise histológica por meio do processamento histológico de coloração com HE e imunohistoquímica utilizando o complexo peroxidase-biotina-streptavidina. A área celular e a expressão do antígeno de proliferação celular nuclear e receptor ß estrogênico foram avaliados. Resultados: Os resultados foram estatisticamente analisados por meio do teste ANOVA e Tukey. Foi observada diminuição na área de células GCT cells no grupo OVX, em contraste com o aumento no grupoe OVX-E. PCNA nas células acinares e receptores de estrógeno estavam aumentados no grupo OVX-I. Conclusão: A castração exerce um efeito indutivo imediato no volume das células GCT. Estrógeno, isoflavona da soja e sua combinação têm diferentes mecanismos de ação sobre a homeostase da glândula. Estrógeno causa um aumento da área de células GCT, enquanto a isoflavona aumenta a proliferação celular e a expressão do receptor-ß de estrógeno. A associação destes não mostrou aumento adicional nos efeitos estudados (AU)

Objective: A decrease in granular convoluted tubule (GCT) cells and acini occurs in the submandibular glands of castrated female rats, while in rats submitted to hormone replacement and phytotherapy with soy isoflavones, this effect is reversed. This study aimed to elucidate the mechanisms through which these changes occur. Material and Methods: Rats (n=84) were ovariectomized and 21 were sham-operated. Ovariectomized rats were randomly subdivided and orally administered the following: 17 ß-estradiol (OVX-E; n=21), 15 mg/kg/day of soy isoflavone extract (OVX-I; n=21), 17 ß-estradiol + soy isoflavone extract (OVX-A; n=21); and water as placebo (OVX; n=21). The rats were euthanized three, five and eight weeks after ovariectomy. The submandibular salivary glands were submitted to histological processing with HE stain and immunohistochemistry was performed using the streptavidin-biotinperoxidase complex. The cell area and the expression of proliferating cell nuclear antigen and estrogen receptor ß were evaluated. Results: The results were statistically analyzed by ANOVA and Tukey test. A decrease in the area of GCT cells in the OVX, was observed, in contrast with an increase in the OVX-E. PCNA in the acinar cells and estrogen receptors were elevated in the OVX-I group. Conclusion: Castration exerts an immediate reductive effect on the volume of GCT cells. Estrogens, soy isoflavones and their combination have different mechanisms of action on the homeostasis of the gland. Estrogens cause an increase in GCT cells area, while isoflavones enhance cell proliferation and the expression of estrogen receptor-ß. Their association showed no additional increase in the effect studied. (AU)

Healing of normal and osteopenic bone with titanium implant and low-level laser therapy (GaAlAs): a histomorphometric study in rats.

The study investigates the influence of low-level laser therapy (LLLT) on bone healing in the femur of osteopenic and normal rats with titanium implants. Ovariectomy and control group were randomly submitted to LLLT, which was applied by gallium-aluminum-arsenium (GaAlAs) laser at the surgical site before and after placing the implant, for seven times. Histomorphometric and statistical analysis were performed. Most irradiated groups showed higher values than the nonirradiated groups. The GaAlAs infrared diode laser may improve the osseointegration process in osteopenic and normal bone, particularly based on its effects in the initial phase of bone formation.

Effect of estrogen therapy, soy isoflavones, and the combination therapy on the submandibular gland of ovariectomized rats.

The objective of this study was to evaluate the effect of estrogen deficiency, estrogen therapy, and soy isoflavones on the salivary glands in female rats. Ninety-six animals were ovariectomized, and 24 were sham-operated. Among the ovariectomized rats, 24 received 17ß-estradiol; 24 received isoflavone extract; 24 received a combination therapy of both; and 24 received water as placebo. The submandibular glands were histomorphometrically analyzed. As a result, the ANOVA test revealed that the hormonal deficiency affected the acini and the ducts of ovariectomized rats, reducing their percentage compared to the sham group. All treatments caused an increase in ducts and acini compared to the placebo group. It was concluded that the estrogen deficiency may be related to salivary gland function due to a reduction in the quantity of salivary acini and ducts secondary to ovariectomy. The estrogen therapy, soy isoflavone therapy, and the combination of both are effective in reducing the effects of ovariectomy on the salivary glands.

Subcutaneous tissue reaction to castor oil bean and calcium hydroxide in rats.

UNLABELLED: Castor oil bean cement (COB) is a new material that has been used as an endodontic sealer, and is a candidate material for direct pulp capping. OBJECTIVE: The purpose of this study was to evaluate the biocompatibility of a new formulation of COB compared to calcium hydroxide cement (CH) and a control group without any material, in the subcutaneous tissue of rats. MATERIAL AND METHODS: The materials were prepared, packed into polyethylene tubes, and implanted in the rat dorsal subcutaneous tissue. Animals were sacrificed at the 7th and 50th days after implantation. A quantitative analysis of inflammatory cells was performed and data were subjected to ANOVA and Tukey's tests at 5% significance level. RESULTS: Comparing the mean number of inflammatory cells between the two experimental groups (COB and CH) and the control group, statistically significant difference (p=0.0001) was observed at 7 and 50 days. There were no significant differences (p=0.111) between tissue reaction to CH (382 inflammatory cells) and COB (330 inflammatory cells) after 7 days. After 50 days, significantly more inflammatory cells (p=0.02) were observed in the CH group (404 inflammatory cells) than in the COB group (177 inflammatory cells). CONCLUSIONS: These results demonstrate that the COB cement induces less inflammatory response within long periods.

Subcutaneous tissue reaction to castor oil bean and calcium hydroxide in rats

Castor oil bean cement (COB) is a new material that has been used as an endodontic sealer, and is a candidate material for direct pulp capping. OBJECTIVE: The purpose of this study was to evaluate the biocompatibility of a new formulation of COB compared to calcium hydroxide cement (CH) and a control group without any material, in the subcutaneous tissue of rats. MATERIAL AND METHODS: The materials were prepared, packed into polyethylene tubes, and implanted in the rat dorsal subcutaneous tissue. Animals were sacrificed at the 7th and 50th days after implantation. A quantitative analysis of inflammatory cells was performed and data were subjected to ANOVA and Tukey's tests at 5 percent significance level. RESULTS: Comparing the mean number of inflammatory cells between the two experimental groups (COB and CH) and the control group, statistically significant difference (p=0.0001) was observed at 7 and 50 days. There were no significant differences (p=0.111) between tissue reaction to CH (382 inflammatory cells) and COB (330 inflammatory cells) after 7 days. After 50 days, significantly more inflammatory cells (p=0.02) were observed in the CH group (404 inflammatory cells) than in the COB group (177 inflammatory cells). CONCLUSIONS: These results demonstrate that the COB cement induces less inflammatory response within long periods.

Homeopathic treatment for bone regeneration: experimental study.

AIM AND METHOD: The objective of this research was to study the effect of homeopathic treatment with Plumbum metallicum (Plumbum met.) on mandibular bone repair in rats. MATERIALS AND METHODS: We analyzed the mandibles of 60 male rats, approximately 3-month-old, randomly divided into three groups of 20 animals each: control, treated with calcitonin, and treated with a homeopathic medicine. A circumscribed bone defect measuring 4mm in diameter was made in the mandible and covered with a polytetrafluorethylene (PTFE) barrier. The group treated with calcitonin received 2IU/kg intramuscularly three times a week; the group treated with Plumbum met. 30c received three drops in water every day. The animals were sacrificed after 7, 14, 21 and 28 days. The mandibles were removed and submitted to histologic and histomorphometric analyses. RESULTS: Data were analyzed statistically by two-way ANOVA and by the Tukey test. The interaction effect (ANOVA, F df(6; 48)=4.64; p=0.001<0.05) indicated that the relationship between treatments was not the same at each time of sacrifice. Although statistical analysis of the histomorphometric data showed a similar results for the treated and control groups. But histological analysis showed complete filling of the surgical defect throughout its extent was only for the group treated with Plumbum met. CONCLUSION: The study demonstrated that for repair of surgical defects in rat mandibles Plumbum met. 30c and control did not differ significantly in histomorphometric terms.

Estudo do efeito do plumbum metallicum 30ch na reparação óssea em mandíbula de ratos sem barreira mecânica / Study of of plumbum metallicum 30ch effect in bone repair of rat mandibles without

Objetivos: O objetivo deste trabalho foi avaliar os efeitos da administração sistêmica do chumbo, preparadode acordo com a farmacotécnica homeopática Plumbum metallicum 30CH, na reparação óssea. Material emétodos: foram utilizados trinta ratos machos com três meses de idade, nos quais foram confeccionadosdefeitos cirúrgicos trans-ósseos com broca de aço nº 06 na região do ângulo da mandíbula do lado direito, semutilização de barreira mecânica. Cada animal do grupo experimental recebeu três gotas diárias de Plumbummetallicum 30CH acrescidas à mamadeira de água. Os animais do grupo controle receberam apenas água. Trêsanimais foram sacrificados nos seguintes períodos experimentais: um, sete, 14, 21 e 28 dias após a cirurgia.Após o sacrifício, as mandíbulas foram removidas, descalcificadas e submetidas ao preparo histológico derotina. Foram submetidas a cortes semi-seriados e coradas pelos métodos de hematoxilina-eosina e tricômicode Masson para análise histológica em microscópio de luz. Resultados: os resultados obtidos neste trabalhomostraram que o medicamento foi eficiente na estimulação da reparação óssea. A análise histológica qualitativamostrou evidência de efeito favorável do Plumbum mettalicum 30 CH. Apesar da interferência dotecido muscular, os animais mostraram, já a partir do período de 14 dias, neoformação óssea em praticamentetoda a extensão do defeito. Conclusão: a utilização do Plumbum metallicum 30CH favoreceu a reparação dedefeitos ósseos em mandíbula de ratos machos, sem a utilização de barreira mecânica.

Histological analysis of effects of 24% EDTA gel for nonsurgical treatment of periodontal tissues.

The aim of this study was to investigate, by means of histological and histomorphometric analysis, the effects of 24% ethylenediaminetetraacetic acid (EDTA) gel in periodontal tissue when used in combination with conventional periodontal treatment. Periodontitis was induced in the 2nd upper left permanent molars of 45 male Wistar rats by means of ligature. After 5 weeks, this was removed and debridement was performed. The animals were then randomly divided into 3 groups; group 1: mechanical treatment, group 2: mechanical treatment and EDTA gel application for 2 min, and group 3: mechanical treatment and placebo gel application for 2 min. After the treatment, rinsing was done with 0.9% saline solution for 1 min in all cases, followed by root notching in the deepest part of the pocket. After 4, 10, and 28 days the animals were sacrificed. The averages obtained were evaluated by means of test two-way analysis of variance (ANOVA) and Tukey statistical tests (P < 0.05). The results showed that with respect to the type of treatment employed, there were no statistically significant differences in the vitality of the periodontal tissue. It was concluded that 24% EDTA gel did not interfere with periodontal tissue repair when used in combination with conventional periodontal treatment.