Estudo do extrato de Ginkgo biloba na prevenção de malformações em recémnascidos de ratas diabéticas

The pregnant women presenting Diabetes mellitus develop metabolic alterations, that may cause damage to the fetal well-being and provoke anomalies and/or malformations. The antioxidant treatment has improved the embryonic development from streptozotocin diabetic rats. Several studies have shown that a Gingko biloba extract presents antioxidant effects and, in the present study, one of the G. biloba extract formulations was used (EGb761) - Tebonin (200 mg/Kg/day), given to the diabetic pregnant female rats. The aim was to evaluate the effect of the EGb761 treatment on the of anomalies and/ or malformations incidence of the offspring. Diabetes was induced in female rats using streptozotocin in a dose of 40 mg/kg. The rats were mated, and the pregnant animals were divided in two groups: Control (water) and experimental (G. biloba). At day 21 of pregnancy, the rats were killed, and their fetuses were analyzed and processed for anomalies and/or malformations incidence. The results demonstrated that control and experimental groups presented no external anomalies and malformations; increased incidence of skeletal anomalies and of visceral malformations, and lower rate of visceral anomalies and skeletal malformations. These data confirm no statistical difference and, therefore, EGb761 treatment did not cause changes. Thus, a dose of 200 mg/Kg/day of a Gingko biloba extract given during the pregnancy rat was ineffective in the prevention of the anomalies and/or malformations related to the diabetes.

Efeito do extrato aquoso de Allium sativum L. sobre parâmetros bioquímicos de ratas com diabete induzido por Streptozotocin

Many plants, even without scientific confirmation, are used in Brazil as hypoglycemic. The objective of the present work was to study the influence of the Allium sativum treatment, plant known popularly as garlic, on characteristic biochemical parameters in streptozotocin-induced diabetic rats. Female Wistar rats were injected with 40 mg kg-1 streptozotocin (STZ). Oral administration of an aqueous extract of A. sativum was given to the diabetic animals in 2 doses: 200 and 400 mg kg-1 (n=6 animals/group). Diabetic rats given distilled water constituted the control group. After 28 days of treatment, the female rats were anesthetized and died by decapitation for collection of the blood for biochemical determinations and retreat of liver samples for hepatic glycogen dosage. The treatment with Allium sativum in the doses of 200 and 400 mg kg-1 alter no concentrations of total proteins, hepatic glycogen, triglycerides and VLDL, but it promoted reduction in the total cholesterol rate (control=280.5 ± 30.9; 200 mg kg-1 A. sativum =169.9 ± 19.5 and 400 mg kg-1 A. sativum =148.4 ± 26.6 mg dL-1) and LDL (control=128.8± 25.3; 200 mg kg-1 A. sativum = 41.4 ± 16.2 and 400 mg kg-1 A. sativum=42.0 ± 26.0 mg dL-1). The extract presented beneficial effect because it decreased 13.0% of glycemia in the highest dose. Therefore, the of garlic extract reduced the HDL concentration in two tested doses (control= 81.4 ± 30.2; 200 mg kg-1 A. sativum=49.6 ± 14.3 and 400 mg kg-1 A. sativum=41.7 ± 16.1 mg dL -1), presenting impaired effect. Thus, the garlic extract showed efficiency in the analyzed experimental conditions, and it could be used as complementary therapy to diabetic patients.

A meniralização dental e a atividade salivar estão reduzidas em filhotes de ratas espontaneamente hipertensas (SHR)

Several pathologies have been diagnosed in children of hypertensive mothers; however, some studies that evaluated the alterations in their oral health are not conclusive. This study analyzed the salivary gland activity and dental mineralization of offsprings of spontaneously hypertensive rats (SHR). Thirty-day-old SHR males and Wistar rats were studied. The salivary flow was evaluated by injection of pilocarpine, the protein concentration and salivary amylase activity, by the Lowry method and kinetic method at 405 nm, respectively. Enamel and dentin mineralization of the mandibular incisors was quantified with aid of the microhardness meter. The results were analyzed by the ANOVA or Student's t test (p<0.05). It was noticed that the salivary flow rate (0.026 mL/min/100 g±0.002) and salivary protein concentration (2.26mg/mL±0.14) of SHR offspring were reduced compared to Wistar normotensive offspring (0.036 mL/min/100 g±0.003 and 2.91 mg/mL±0.27, respectively), yet there was no alteration in amylase activity (SHR: 242.4 U/mL±36.9; Wistar: 163.8 U/mL±14.1). Microhardness was lower both in enamel (255.8 KHN±2.6) and dentin (59.9 KHN±0.8) for the SHR teeth compared to the Wistar teeth (enamel: 328.7 KHN±3.3 and dentin: 67.1 KHN±1.0). These results suggest that the SHR offspring are more susceptible to development of pathologies impairing oral health, once they presented lesser flow and salivary protein concentration and lower dental mineralization.

Efeito do extrato aquoso de folhas de Polymnia sonchifolia (yacon) em ratas diabéticas

Polymnia sonchifolia is a medicinal plant used as hypoglycemic agent and other ends. The aim was to evaluate the yacon effect on diabetes in Wistar female rats, which was divided in 4 groups: non-diabetic (n=24) given (gavage) 32.4 mg kg -1 of an aqueous extract of plant (treated group) or vehicle (non-treated group), and one diabetic group (n=24) with similar treatment compared to non-diabetic rats. Diabetes was induced using streptozotocin (i.v. route, 40 mg kg -1). Glycemia was monitored after rodent adaptation period, 15 days after diabetes induction, and each 10 days after yacon/vehicle in early treatment. During experiment period, body weights, food and water intake were daily measured. The rats (non-diabetic or diabetic) given yacon extract treatment presented no significant difference related with glycemia, body weight gain, and food and water intake. Thus, further studies such increase of rat number in agreement with different glycemic levels and increase of the plant extract dose are necessary.

Os efeitos de um programa de atividade física de carga progressiva nas propriedades físicas e na força óssea de ratas osteopênicas

Background: Many studies have shown that physical exercises are able to stimulate bone formation and increase bone mass, constituting a therapeutic modality to treat bone loss due to osteoporosis. However, some points about the intensity, duration and frequency of the exercises remain confusing and contradictory. Thus, the aim of this study was to determine the effects of a progressive loading exercise program on femur of osteopenic rats. To induce osteopenia we used the animal model of ovariectomy (OVX). Forty animals was studied and divided into 4 groups: sham-operated sedentary (SS); ovariectomy-sedentary (OS); sham-operated training (ST) and ovariectomy training (OT). The trained groups performed jumps into water: 4 series of 10 jumps each, with an overload of 50% to 80% of the animal's body weight, during 8 weeks. Femora were submitted to a physical properties evaluation, a biomechanical test, calcium and phosphorus content measurement and a morphometric histological evaluation. Results: osteopenic animals showed a decrease of bone strength and lower values of bone weights, bone density and calcium content. The exercised osteopenic rats showed higher values of geometrical, physical properties, bone strength and calcium content compared to controls. The results of the present study indicate that the progressive loading exercise program had stimulatory effects on femora of osteopenic rats. It seems that the intensity and duration of the protocol used produced bone structural adaptations, which contributed to reverse bone loss due to ovariectomy.

Efectos de la administración de betabloqueante en la remodelación ventricular inducida por el tabaquismo en ratas

Background: The role of the adrenergic system on ventricular remodeling induced by cigarette smoking is unknown. Objective: To investigate the influence of propranolol on ventricular remodeling induced by exposure to tobacco smoke. Methods: Rats were divided into three groups: 1) C, n=10 - control group; 2) F, n=10 - animals exposed to tobacco smoke; 3) BB, n=10 - animals receiving propranolol and exposed to tobacco smoke (40 mg/kg/day). After 2 months, the animals underwent echocardiographic and morphometric analyses. One-way ANOVA (mean ± standard deviation) or the Kruskal-Wallis test (median and interquartile interval) was used. Results: Group BB showed a lower heart rate than group F (C = 358 ± 74 bpm, F = 374 ± 53 bpm, BB = 297± 30; P = 0.02). Group F showed greater end-diastolic diameters (C = 18.6 ± 3.4 mm/kg, F = 22.8 ± 1.8 mm/kg, BB = 21.7 ± 1.8 mm/kg; P = 0.003) and left ventricular (LV) end-systolic diameters (C = 8.6 ± 2.1 mm/kg, F = 11.3 ± 1.3 mm/kg, BB = 9.9 ± 1.2 mm/kg; P = 0.004), adjusted for body weight (BW) and a tendency towards a lower ejection fraction (C = 0.90 ± 0.03, F = 0.87 ± 0.03, BB =0.90 ± 0.02; P = 0.07) than group C. Group BB showed a tendency towards a lower LV/BW ratio than group F (C = 1.94 (1.87 - 1.97), F = 2.03 (1.9-2.1) mg/g, BB = 1.89 (1.86-1.94); P = 0.09). Conclusion: Administration of propranolol attenuated some of the variables of ventricular remodeling induced by the exposure to tobacco smoke in rats.

Efeito da exposição à fumaça de cigarro durante a prenhez e a lactação de ratas e sua prole sobre parâmetros séricos e morfométricos

PURPOSE: to investigate the effect of cigarette smoke exposure on body and tissue weight gain, serum parameters and milk yield during pregnancy and lactation in rats, and the impact on offspring from birth toil young adulthood. METHODS: 40 Wistar pregnant rats were randomly divided into: CG - not exposed to cigarette smoke and sacrificed at the end of pregnancy; CL - not exposed to cigarette smoke and sacrificed at the end of lactation; FG - exposed to cigarette smoke and sacrificed at the end of pregnancy; FL - exposed to cigarette smoke and sacrificed at the end of lactation. The offspring were separated by gender and divided according to their mothers' groups. Tissue weight, body weight and serum parameters were evaluated in rats and offspring. Milk yield per pup was calculated. RESULTS: body weight was decreased in FL during lactation (CL=267.0±7.2; FL=235.5±7.2 g*, *p<0.05). Adipose tissue was not detected in the CL and FL groups, and was reduced in FG compared to CG (CG=3.3±0.3; FG=2.4±0.3 g*, *p<0.05). Rats exposed to cigarette smoke had higher blood glucose levels (CG=113±17, CL=86±16, FG=177±21*, FL=178±23 mg/dL*, *p<0.05 CG versus FG e CL versus FL), CL and FL groups presented lower HDL-cholesterol with no change in total cholesterol. Finally, rats exposed to cigarette smoke had lower milk yield compared to unexposed rats (CL=6.7±0.4, FL=5.4±0.3 g*, *p<0.05). In offspring from the FG and FL groups, there was a decrease of body weight from birth to young adulthood, with no changes in gastrocnemius, liver or heart weights in any group, and adipose tissue was no detected in female offspring. There was an increase in blood glucose in offspring of both sexes from rats exposed to cigarette smoke (males: Pcg=107±10.5, Pcl=115±8.6, Pfg=148±16.8*, Pfl=172±11.2**; females: Pcg=109±27.2, Pcl=104±9.7, Pfg=134±20.0*, Pfl=126±13.3**; p<0.05 *Pcg versus Pfg and **Pcl versus Pfl). CONCLUSIONS: exposure to cigarette smoke provokes impairment of morphometric and serum parameters during pregnancy and lactation both in mothers and offspring, which is maintained during young adulthood.

Efeito do exercício aeróbio na menopausa induzida por ooforectomia: estudo clínico, biomecânico e densitométrico em ratas

Pós-graduação em Bases Gerais da Cirurgia - FMB

Efeito da exposição à fumaça de cigarro sobre a expressão de GLUT4 em ratas prenhes e lactantes e sua prole

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo clínico, biomecânico e histológico do efeito da menopausa induzida por ooforectomia no tecido ósseo. Modelo experimental em ratas

Pós-graduação em Bases Gerais da Cirurgia - FMB

Desenvolvimento sexual da prole de ratas submetidas à restrição proteica em diferentes períodos da prenhez e lactação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da osteoporose e álcool na osseointegração de implantes em ratas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo comparativo de reparação óssea em ratas ovariectomizadas tratadas com risedronato e Calcarea fluorica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da osteopenia na reparação do enxerto ósseo autógeno associado ou não por membrana de PTFE-e: estudo histológico e histomorfométrico em ratas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do consumo de iogurte de soja suplementado com isoflavonas e cálcio sobre o tecido ósseo de ratas maduras ovariectomizadas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)