Protective effect of melatonin against herbicides-induced hepatotoxicity in rats.

Exposure to the herbicides Paraquat and Roundup® may cause cell lesions due to an increase in oxidative stress levels in different biological systems, even in the liver. The aim of this study was to analyze the effect of melatonin on liver of rats exposed to herbicides. A total of 35 rats were randomly divided into seven equal-sized groups: control, Paraquat, Roundup®, Paraquat + Roundup®, Paraquat + melatonin, Roundup® + melatonin, and Paraquat + Roundup® + melatonin. Samples of blood and hepatic tissue were collected at the end of the seventh day of exposure and treatment with melatonin. Body weight, hematological parameters, and histopathological, biochemical analyses and determination of oxidative stress levels in liver were evaluated. Body weight was compromised (P < 0.01). Alterations of hematologic parameters were significant when compared to control (P < 0.001). Biochemically, serum levels of albumin decreased (P < 0.001), but serum levels of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase increased (P < 0.001). Histopathology revealed necrotic hepatocytes, portal and central-lobular inflammatory infiltrate, congestion of capillaries. Serum levels of thiobarbituric acid reactive substances were found to be significantly elevated (P < 0.05; P < 0.001), and serum level of reduced glutathione was significantly lower (P < 0.05; P < 0.001). The groups treated concomitantly with melatonin revealed results similar to those of the control. However, melatonin acted as a protective agent for the liver against experimentally induced hepatic toxicity, promoting prevention of body weight, oxidative stress, and normalization of hematological and biochemical parameters.

Melatonin on hypothyroidism and gonadal development in rats: a review.

We evaluated the evidence in research on the effects of melatonin on hypothyroidism and gonadal development. According to the World Health Organization, thyroid disorders due to iodine deficiency affect about 740 million people worldwide. Hypothyroidism is a thyroid dysfunction characterized by hypometabolism of the gland, with reduced or physiologically normal T3 and T4 serum levels, and high TSH level. This disorder occurs mainly in adult women in the reproductive phase, with a prevalence of 2% among the world's female population, with profound repercussions on gestation and fetal formation. During the gestational period, the thyroid is initially stimulated by high concentrations of human chorionic gonadotrophin; thus, maintaining maternal euthyroidism during pregnancy and lactation is fundamental for fetal growth and development. Besides, the hormones produced by this gland are involved in the formation of various organs, such as the skin, brain and gonads. Hypothyroidism is associated with several menstrual abnormalities, anovulation and hyperprolactinemia, resulting in a high rate of abortions, premature births, placental rupture, and weight-related neonatal deficits. In addition, there are studies showing that hypothyroidism can affect ovarian morphology (number of ovarian follicles) and testicular morphology (changes in the testicular-lumen epithelium). Melatonin is a hormone known to modulate the estrous cycle and pregnancy, and studies show that the exogenous application of melatonin increased T4 levels in female rats and controlled the decrease in T3 serum levels, reverting the sigs of hypothyroidism.

Application of platelet-rich plasma in the in vitro production of bovine embryos.

The aim of this study was to replace fetal bovine serum (FBS) with platelet-rich plasma (PRP) for in vitro production of bovine embryos. The maturation media (TCM-199 medium) for the cumulus-oocyte complexes (COCs) was supplemented with 5% (G5) and 10% (G10) PRP or 10% FBS (GC). After fertilization, the presumed zygotes were randomly distributed in culture medium supplemented with 5% (G5) and 10% (G10) PRP or 10% FBS (GC) for 7 days. Cumulus cell (CC) expansion was greater (P < 0.05) in the GC (88.9%) group than in G5 (34.1%) or G10 (50.0%). Nevertheless, the expansion of CCs in group G10 was greater than in G5 (P < 0.05). Cleavage was higher in group G5 (86.0%) than in G10 (79.0%) (P < 0.05) and did not differ from group GC (82.0%). The percentage of blastocysts in group G5 (50.0%) was higher than in CG (40.2%) and G10 (34.2%) (P < 0.05). In addition, the number of blastomeres was higher in G5 (159.0 ± 4.18) than in GC (132.4 ± 4.11) and in G10 (127.1 ± 5.88) (P < 0.05). The addition of PRP into the oocytes maturation medium is not beneficial. On the other hand, the PRP addition into the embryo culture medium at 5% concentration is recommended where it increased the quantity and quality of in vitro-produced bovine embryos.

Melatonin regulates the expression of inflammatory cytokines, VEGF and apoptosis in diabetic retinopathy in rats.

The present study analyzed whether melatonin could mediate the expression of VEGF, IL-6 and TNF-α, as well as the apoptotic index in rats with diabetic retinopathy. Fifty Wistar albino rats were divided into the following groups: GC: rats without induction of diabetes by streptozotocin; GD: rats induced to diabetes by streptozotocin and treated with placebo; GDM: rats induced to diabetes by streptozotocin and after confirmation treated with melatonin at a dose of 10 mg/kg for 20 days; GDMS: rats induced to diabetes by streptozotocin and treated simultaneously with melatonin at a dosage of 10 mg/kg for 20 days; GDI: rats induced to diabetes by streptozotocin and after confirmation treated with insulin for 20 days. Diabetes was induced by intraperitoneal injections of streptozotocin (60 mg/kg), and insulin (5 U/day) was administered subcutaneously. For apoptosis TUNEL was used, while for the analysis of VEGF, IL-6 and TNF-α. The results showed that the groups that were treated with melatonin decreased the expression of cytokines and VEGF, in addition to apoptosis. Thus, it is concluded that melatonin can regulate the expression of these factors by improving the condition of the retina in diabetic retinopathy.

Evaluation of Piper marginatum (Piperales: Piperaceae) Oil and Geraniol on the Embryonic Development of Spodoptera frugiperda (Lepidoptera: Noctuidae) in Comparison to Formulated Products.

Essential oils and their isolated constituents are constantly being studied for the control of insect pests. In this context, the present research reports the chemical composition of Piper marginatum (Jacq.) oil aiming to: 1) establish lethal concentrations LC30 and LC50 for this oil and the compound geraniol, 2) histologically examine the embryonic development of Spodoptera frugiperda (J.E. Smith) through light microscopy and scanning electron microscopy (SEM), as well as 3) compare the efficacy of the P. marginatum oil with that of the botanical insecticide azadirachtin, the synthetic insecticide deltamethrin, and acetone as a negative control. Semithin sections of S. frugiperda eggs revealed that the oil, geraniol, azadirachtin, and deltamethrin affected embryonic development at both concentrations. However, geraniol and the oil were more efficient because they caused more significant damage, even at lower concentrations. SEM revealed that all products altered the morphology of the eggs, modifying the structure of the chorion and making the eggs nonviable. Thus, this work demonstrates that P. marginatum oil is effective in the control of S. frugiperda because it results in embryonic damage even at the lowest concentrations.

Genotoxic and mutagenic evaluation of the protective effect of exogenous melatonin in adult rats and their offspring exposed to the insecticides methomyl and cypermethrin during pregnancy.

Exposure of pregnant women to pesticides in an occupational or incidental manner has been pointed out as a possible cause of health problems in newborns. Cypermethrin and methomyl are insecticides whose active compounds and metabolites can cause harm to the health of pregnant women and their offspring. Both contribute to increases in the concentrations of oxidizing agents that damage DNA, causing mutations. Thus, the use of antioxidant substances, such as melatonin, could serve as protection against genetic damage, reducing the problems caused by insecticides. Here, we evaluated the protective effect of exogenous melatonin in adult rats and their offspring exposed to methomyl and cypermethrin during the gestational period. Thirty adult rats were divided into five groups from the first day of pregnancy: NC - negative control, Mth received 0.02 mg/kg/day of methomyl, Cyp received 0.05 mg/kg/day cypermethrin, MthMl received 0.02 mg/kg/day methomyl combined with 10 mg/kg/day melatonin, and CypMl received 0.05 mg/kg/day cypermethrin combined with 10 mg/kg/day melatonin. Blood and liver samples were collected from the dams; blood, liver, and brain samples were collected from the offspring. All tissues were used for comet assay; blood was used for micronucleus test. Our results demonstrate that cypermethrin and methomyl induce significant genetic damage in the tissues of dams and offspring. Treatment with melatonin significantly reduced cypermethrin-induced genetic damage in dams and pups; however, melatonin was not effective against the genetic damage caused by methomyl. Thus, melatonin may be considered a promising agent for the reduction of genotoxic effects induced by cypermethrin but appears to be inefficient against the genotoxic effects caused by methomyl, probably due to differences in the metabolism of each pesticide.

Análise histológica do estômago da prole de ratas Wistar submetidas ao consumo crônico de álcool durante a prenhez / Histological analysis of stomach of offspring of Wistar rats submitted to chronic alcohol consumption during pregnancy

O consumo de bebidas alcoólicas na gravidez consiste em um importante problema de saúde pública, visto que, pode causar prejuízos na organogênese de diversos órgãos, incluindo o estômago, entretanto, poucos estudos avaliam o efeito da exposição pré-natal ao álcool nesse órgão. O objetivo deste estudo foi analisar histologicamente o estômago da prole de ratas submetidas ao consumo crônico de álcool durante a prenhez. Utilizou-se 10 ratas prenhes divididas nos grupos: Controle - ratas que receberam água destilada durante todo período gestacional e Álcool ­ ratas que receberam álcool etílico absoluto (3g/kg/dia) durante todo período gestacional. Logo após o nascimento, 12 neonatos (6 machos e 6 fêmeas) de cada grupo foram anestesiados e os estômagos coletados. Posteriormente, os órgãos foram fixados e processados seguindo a técnica histológica de rotina. Foram feitas análises histomorfométricas das camadas mucosa, muscular e da parede total do estômago. Observou-se que as proles macho e fêmea expostas ao etanol apresentaram diminuição da área de epitélio, contudo, os machos também mostraram redução significativa do número de células epiteliais. Demonstrou-se ainda redução na espessura das camadas mucosa, muscular e da parede total do estômago da prole fêmea do grupo Álcool. No entanto, a camada muscular apresentou aumento significativo em sua espessura no grupo de neonatos machos expostos ao etanol. Assim, concluímos que a exposição pré-natal ao álcool provoca efeitos nocivos sobre o estômago dos neonatos, contudo, estudos futuros são necessários para melhor elucidar os mecanismos envolvidos na patogênese e possíveis consequências para os animais na fase adulta.

Consumption of alcoholic beverages during pregnancy is a significant public health issue since it can damage the organogenesis of several organs, including the stomach; however, few studies evaluate the effect of prenatal exposure to alcohol in this organ. The objective of this study was to analyze the histology of the stomach of offspring of rats submitted to chronic alcohol consumption during pregnancy. Ten pregnant rats were divided into two groups: Control - rats receiving distilled water throughout the gestation period, and Alcohol - rats receiving absolute ethyl alcohol (3g/kg/day) throughout the gestation period. After birth, 12 newborn rats (6 males and 6 females) from each group were anesthetized and their stomachs were collected. Subsequently, the organs were fixed and processed following the routine histological technique. The mucosa, muscle and total stomach were submitted to histomorphometric analyses. It was observed that the male and female offspring exposed to ethanol had a decrease in the epithelium area. However, males also showed a significant reduction in the number of epithelial cells. There was also a reduction in the layer's thickness mucosa, muscle and total stomach wall of the female offspring from the alcohol group. Additionally, the muscular layer presented a significant increase in its thickness in the group of male neonates exposed to ethanol. It can be concluded that prenatal exposure to alcohol causes harmful effects on neonates' stomachs; however, future studies are necessary to better elucidate the mechanisms involved in the pathogenesis and possible consequences for the animals in adulthood.

Bone marrow-derived monocyte infusion improves hepatic fibrosis by decreasing osteopontin, TGF-ß1, IL-13 and oxidative stress.

AIM: To evaluate the therapeutic effects of bone marrow-derived CD11b+CD14+ monocytes in a murine model of chronic liver damage. METHODS: Chronic liver damage was induced in C57BL/6 mice by administration of carbon tetrachloride and ethanol for 6 mo. Bone marrow-derived monocytes isolated by immunomagnetic separation were used for therapy. The cell transplantation effects were evaluated by morphometry, biochemical assessment, immunohistochemistry and enzyme-linked immunosorbent assay. RESULTS: CD11b+CD14+ monocyte therapy significantly reduced liver fibrosis and increased hepatic glutathione levels. Levels of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-6 and IL-1ß, in addition to pro-fibrotic factors, such as IL-13, transforming growth factor-ß1 and tissue inhibitor of metalloproteinase-1 also decreased, while IL-10 and matrix metalloproteinase-9 increased in the monocyte-treated group. CD11b+CD14+ monocyte transplantation caused significant changes in the hepatic expression of α-smooth muscle actin and osteopontin. CONCLUSION: Monocyte therapy is capable of bringing about improvement of liver fibrosis by reducing oxidative stress and inflammation, as well as increasing anti-fibrogenic factors.

Lufenuron impact upon Anthonomus grandis Boheman (Coleoptera: Curculionidae) midgut and its reflection in gametogenesis.

The insecticide Match® (lufenuron), one of the main insect growth regulators used in pest control, has been presented as a viable alternative against the boll weevil, Anthonomus grandis (Coleoptera: Curculionidae), by inhibiting chitin synthesis. Thus, this study aimed to examine whether Match® interferes in the synthesis of the peritrophic matrix, leading to changes in the midgut epithelium, resulting in nutritional deficiency and reflecting, thereby, in the gametogenesis process of A. grandis. Floral cotton buds were immersed in the insecticide solution (800µL of Match®+200mL of distilled water) and offered to the adult insects. The midguts of the insects were evaluated after 24 and 120h after feeding. The gonads were evaluated after 120h. The results showed that Match®, in both evaluation periods, induced histopathological alterations such as disorganization, vacuolization and desquamation of the midgut epithelium; histochemical modifications in the distribution patterns of carbohydrates, although without quantitative changes; and a strong decrease in protein levels. No apoptosis were observed, however, there was an increase in the number of regenerative cell nests. In the testicles, a reduction in the amount of spermatozoids and reduced carbohydrate levels were observed, but no difference in protein levels. The ovarioles presented structural disorganization of follicular cells, yolk reduction and decrease in protein levels, however, no change in carbohydrates levels was noted. Therefore, it is concluded that Match® performs histopathologic and histochemical alterations in the midgut epithelium and the gonads of A. grandis adults, reflecting in the gametogenesis process, presenting itself as a promising tool in the management of this pest on cotton crops.

Histological and histochemical changes by clove essential oil upon the gonads of Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) / Alteraciones histológicas e histoquímicas provocadas por el aceite esencial de clavo de olor en las gónadas de Spodoptera frugiperda ( je smith ) (Lepidoptera: Noctuidae)

Spodoptera frugiperda is a polyphagous insect that causes economic losses to several crops in Brazil and is the major obstacle to corn production. Researches focusing on alternative control, e.g. botanical products are expanding to offer a wide variety of molecules that interfere with different biological parameters of insect pests. Thus, this study tested the hypothesis that clove essential oil affects the spermatogenesis, ovarioles histochemistry and the fertility of S. frugiperda. The results showed that clove essential oil affects the gametogenesis of S. frugiperda ovarioles, reflecting negatively on its reproduction, proving to be a promising tool for controlling this pest.

Spodoptera frugiperda es un insecto polífago que causa pérdidas económicas a varias cosechas en Brasil y es el mayor obstáculo para la producción de maíz. Este estudio está centrado en el control alternativo, con productos botánicos que se están expandiendo y ofrecen una amplia variedad de moléculas que interfieren con diferentes parámetros biológicos de plagas de insectos. Por tanto, se puso a prueba la hipótesis de que el aceite esencial de clavo de olor afecta la espermatogénesis. La histoquímica de los ovarioles y la fertilidad de S. frugiperda. Los resultados mostraron que el aceite esencial de clavo de olor afecta la gametogénesis de los ovarioles en S. frugiperda, lo que incide negativamente en su reproducción, demostrando ser una herramienta prometedora para el control de esta plaga.

Effects of melatonin and prolactin in reproduction: review of literature.

The pineal gland is responsible for producing a hormone called melatonin (MEL), and is accepted as the gland that regulates reproduction in mammals. Prolactin (PRL) also exhibits reproductive activity in animals in response to photoperiod. It is known that the concentrations of PRL are high in the summer and reduced during winter, the opposite of what is seen with melatonin in these seasons. In placental mammals, both prolactin and melatonin affect implantation, which is considered a critical point of pregnancy, since a successful pregnancy requires the development of a synchronous interaction between the endometrium and blastocyst for placental development. It is also known that PRL levels during pregnancy are essential for the maintenance of pregnancy, because this hormone induces the corpus luteum to produce progesterone, in addition to stimulating blastocyst implantation to maintain pregnancy and form the placenta. However, melatonin levels in plasma have also been shown to increase during pregnancy, peaking at the end of this period, which suggests that this hormone plays an important role in the maintenance of pregnancy. Thus, it is clear that treatment with prolactin or melatonin interferes with the processes responsible for the development and maintenance of pregnancy.

Effects of melatonin and prolactin in reproduction: review of literature / Efeitos da melatonina e da prolactina na reprodução: revisão de literatura.

Summary The pineal gland is responsible for producing a hormone called melatonin (MEL), and is accepted as the gland that regulates reproduction in mammals. Prolactin (PRL) also exhibits reproductive activity in animals in response to photoperiod. It is known that the concentrations of PRL are high in the summer and reduced during winter, the opposite of what is seen with melatonin in these seasons. In placental mammals, both prolactin and melatonin affect implantation, which is considered a critical point of pregnancy, since a successful pregnancy requires the development of a synchronous interaction between the endometrium and blastocyst for placental development. It is also known that PRL levels during pregnancy are essential for the maintenance of pregnancy, because this hormone induces the corpus luteum to produce progesterone, in addition to stimulating blastocyst implantation to maintain pregnancy and form the placenta. However, melatonin levels in plasma have also been shown to increase during pregnancy, peaking at the end of this period, which suggests that this hormone plays an important role in the maintenance of pregnancy. Thus, it is clear that treatment with prolactin or melatonin interferes with the processes responsible for the development and maintenance of pregnancy.

Resumo A glândula pineal é responsável pela produção do hormônio melatonina (MEL), sendo aceita como a glândula reguladora da reprodução em mamíferos. A prolactina (PRL) também exibe atividade reprodutiva em animais, em resposta ao fotoperíodo. Sabe-se que as concentrações de PRL são elevadas durante o verão e baixam durante o inverno, ocorrendo o oposto com os níveis do hormônio melatonina nessas estações. Nos mamíferos placentários, tanto a melatonina quanto a prolactina influenciam a implantação, que é considerada o ponto crítico da gravidez, pois o sucesso da gestação requer o desenvolvimento de uma interação sincronizada entre o endométrio e o blastocisto para o desenvolvimento da placenta. Sabe- -se ainda que os níveis de PRL durante a gestação são essenciais para a manutenção da gravidez, pois esse hormônio induz o corpo lúteo a produzir progesterona, além de estimular a implantação do blastocisto, mantendo a prenhez e o desenvolvimento placentário. Em contrapartida, tem-se demonstrado também que os níveis de melatonina no plasma aumentam durante a gestação, atingindo valores elevados no fim desse período, sugerindo que esse hormônio desempenhe um importante papel na manutenção da gestação. Dessa forma, fica claro que o tratamento com prolactina ou melatonina interfere nos processos responsáveis pelo desenvolvimento e pela manutenção da gestação.

Efeitos de isolados do fungo Isaria (Persoon) sobre o cupim subterrâneo Coptotermes gestroi (Wasmann) (Isoptera: Rhinotermitidae) / Effects of Isaria (Persoon) isolates on the subterranean termite Coptotermes gestroi (Wasmann) (Isoptera: Rhinotermitidae)

Coptotermes gestroi (Wasmann) é considerada uma das espécies mais destrutivas de cupins subterrâneos, por causar danos a edificações, à arborização urbana e a culturas. Uma alternativa para o controle desse inseto pode ser o uso de agentes biocontroladores, como os fungos entomopatogênicos. Isaria (Persoon) tem sido indicado no controle de térmitas subterrâneos, inclusive do gênero Coptotermes. Dessa forma, o presente trabalho teve como objetivo selecionar isolados de Isaria patogênicos ao cupim C. gestroi. Os insetos pulverizados com suspensões fúngicas de I. farinosa, I. fumosorosea e I. javanica foram avaliados diariamente para a determinação da mortalidade. Todos os isolados foram patogênicos, ocasionando mortalidade acima de 70%, e virulentos, apresentando uma sobrevivência média de 2,0 a 3,9 dias. Contudo, os isolados ESALQ-1205 de I. farinosa, ESALQ-1296 de I. fumosorosea e os isolados URM-4995 e URM-4993 de I. javanica mostraram-se mais virulentos. A CL50estimada para os isolados ESALQ-1205 de I. farinosa, URM-4995 de I. javanica e ESALQ-1296 de I. fumosorosea resultou em valores de 3,7 x 105, 1,4 x 106e 2,7 x 106conídios mL-1, respectivamente. Tais resultados confirmam a eficiência dos isolados testados sobre os operários de C. gestroi. No entanto, novos estudos são necessários para verificar a melhor forma de utilização, bem como a sua efetividade em campo.(AU)

Coptotermes gestroi (Wasmann) is considered to be one of the most destructive species of subterranean termites because of the damage caused on edifications, urban trees, and crops. One alternative to control it is the use of biocontrol agents, such as the entomopathogenic fungi. The genus Isaria (Persoon) has been suggested for the control of subterranean termites, including the Coptotermes genus. Therefore, the present work aim was to select isolates of Isaria pathogenic to C. gestroi. The workers were sprayed with fungi suspensions of I. farinosa, I. fumosorosea and I. javanica, and evaluated every day to determine mortality. All isolates were pathogenic towards C. gestroi with mortality rates higher than 70%, and virulent, with mean of survival of 2.0 up to 3.9 days. Among the isolates, the ESALQ-1205 isolate of I. farinosa, the ESALQ-1296 isolate of I. fumosorosea, URM-4995 and URM-4993 isolates of I. javanica showed the highest virulence. The estimated CL50 for the ESALQ-1205 isolate of I. farinosa, URM-4995 isolate of I. javanica and ESALQ-1296 isolate of I. fumosorosea was 3.7 x 105, 1.4 x 106and 2.7 x 106 conidia mL-1, respectively. These results suggest high efficiency of these isolates towards the C. gestroi workers. Nevertheless, further studies are necessary to determine a way of using them as well as their efficacy in field.(AU)

Histopathology of organs from neonate offspring born to female rats exposed to sublethal doses of biological and synthetic insecticides / Histopatología de órganos de ratas recién nacidas sometidas a dosis subletales de insecticidas sintéticos y biológicos

The current annual consumption of insecticides in agriculture in Brazil is over three million tons. The exposure happens through food that is contaminated with toxic waste and respiratory and dermal absorption. Biological control with Bacillus thuringiensis Berliner (Bt) has assumed increasing importance replacing the use of conventional insecticides. However, the tests used to justify approval for use and market release of Bt products, and the protocols used to assess the development of toxicity, are extremely superficial. In addition, more studies comparing effects between males and females and during pregnancy and lactation have not been conducted. Thus, the hypothesis tested in this study was if the administration of the XenTari® WG (Bacillus thuringiensis subsp. Aizawai) biological insecticide and Decis® 25CE (Deltamethrin) synthetic insecticide, at concentrations that do not cause clinical signs of maternal toxicity, could interfere in the histophysiology of the organs of neonate rats. Thirty-five pregnant albino rats, Rattus norvegicus albinus, were randomly distributed in seven groups: Group I received placebo (water); Groups II, III, and IV received 1.0, 10.0, and 20.0 mg of XenTari®/kg respectively; and Groups V, VI, and VII received 1.0, 2.0, and 4.0 mg of Deltamethrin/kg, respectively. The results showed that the highest doses of insecticides reduced the number of neonates. No histopathological alterations were observed in the kidneys, however, lipidosis, diffuse mononuclear inflammatory cells, and sinusoids congestion were observed in the liver. Rats from groups IV and VII presented atresia in the ovaries. Neonates from Group IV showed congestion and hemosiderin deposition in the testicle's blood vessels, which is characteristic of a process of hemolysis. In conclusion, both insecticides presented similar effects on organs and number of neonates born to rats exposed to sub-lethal doses that did not cause clinical symptoms of maternal intoxication.

El consumo anual actual de insecticidas en la agricultura en Brasil es más de tres millones de toneladas. Aproximadamente el 60% de los trabajadores rurales expuestos a los insecticidas son mujeres. La exposición ocurre a través de alimentos contaminados con desechos tóxicos y la absorción respiratoria y dérmica. El control biológico con Bacillus thuringiensis Berliner (Bt) ha adquirido una importancia creciente en la sustitución del uso de insecticidas convencionales. Sin embargo, las pruebas utilizadas para justificar la aprobación para el uso y la liberación del mercado de los productos Bt, y los protocolos utilizados para evaluar el desarrollo de toxicidad, son muy superficiales. Además, no se han realizado estudios que que permitan comparar los efectos entre hombres y mujeres y durante el embarazo y la lactancia. Por lo tanto, la hipótesis planteada en este estudio fue si la administración del Grupo de Trabajo XenTari ® (B. thuringiensis subsp. Aizawai) insecticida biológico y Decis ® 25CE (deltametrina) insecticidas sintéticos, en concentraciones que no causan signos clínicos de toxicidad materna, podría interferir en la histofisiología de los órganos de las ratas recién nacidas. Treinta y cinco ratas albinas preñadas, Rattus norvegicus albino, fueron distribuidas aleatoriamente en siete grupos: Grupo I recibió un placebo (agua), los Grupos II, III y IV recibieron 1,0, 10,0 y 20,0 mg de XenTari ® / kg, respectivamente, y Grupos V, VI y VII recibieron 1,0, 2,0 y 4,0 mg de deltametrina / kg, respectivamente. Los resultados mostraron que las dosis más altas de insecticidas redujeron el número de neonatos. No se observaron alteraciones histopatológicas en los riñones, sin embargo, se observaron en el hígado, lipidosis, difusas células inflamatorias mononucleares, y la congestión de sinusoides. Las ratas de los grupos IV y VII presentaron atresia ovárica. Los recién nacidos de grupo IV mostraron congestión y depósito de hemosiderina en los vasos sanguíneos del testículo, lo cual es característico de un proceso de hemólisis. En conclusión, los insecticidas presentaron efectos similares en los órganos y en el número de recién nacidos de ratas expuestas a dosis sub-letales, que no causan síntomas clínicos de toxicidad materna.

Analysis of fetal and placental development in rats after administration of hydroalcoholic extract from the root of Petiveria alliacea L. (Phytolaccaceae) / Análisis del desarrollo fetal y placenta en ratas después de la administración de extracto hidroalcohólico de la raíz de Petiveria alliacea L. (Phytolaccaceae)

We investigated the effect of hydroalcoholic extract the Petiveria alliacea root on fetal and placental development female rats pregnancy. Thirty female rats were mated and divided in groups: I - rats treated with placebo and sacrificed on the 7th day; II - rats treated with hydroalcoholic extract and sacrificed on the 7th day; III - rats treated with placebo and sacrificed on the 14th day; IV - rats treated with hydroalcoholic extract and sacrificed on the 14th day; V - rats treated with placebo for analysis of the offspring; VI - rats treated with hydroalcoholic extract for analysis of the offspring. The extract was administered by gavage in the dosage of 18mg/kg body wt., in 5th day of pregnancy. The implantation sites and placenta were fixed in Bouin and processed for the embedding in paraffin. The offspring were weighed, measured and counted. The hydroalcoholic extract of the root of the P. alliacea causes significant reduction in the number of implantation sites, but do not cause histological alterations in these sites and placenta. No alterations in the number, length and weight have been observed in offspring. Our results suggest that the hydroalcoholic extract from the P. alliacea in the dosage of 18mg/kg body wt., administered to female rats, on the 5th day of pregnancy, only cause a retard in the implantation process.

Se investigaron los efectos de la extracto hidroalcohólico de la raíz Petiveria alliacea sobre el desarrollo fetal y placentario en ratas preñadas. Treinta ratas hembras fueron criadas y divididas en grupos: I- Ratas tratadas con placebo y sacrificado en el día 7; II- Ratas tratadas con el extracto hidroalcohólico y sacrificadas en el día 7; III- ratas tratadas con placebo y sacrificado el día 14; IV- ratas tratadas con el extracto hidroalcohólico y sacrificaron el día 14; V- ratas tratadas con placebo para el análisis de las crías; VI- ratas tratadas con el extracto hidroalcohólico para el análisis de las crías. El extracto se administró por sonda en dosis de 18mg/kg de peso corporal, en el 5to día de preñez. Los sítios de implantación y la placenta se fijaron en Bouin y se procesaron para la inclusión en parafina. Las crías fueron pesadas, medidas y contadas. El extracto hidroalcohólico de la raíz de P. alliacea provocó una reducción significativa en el número de sitios de implantación, pero no causaron alteraciones histológicas en estos sitios y la placenta. No se observaron alteraciones en el número, longitud y peso de las crías. Nuestros resultados sugieren que el extracto hidroalcohólico de P. alliacea en la dosis de 18mg/kg de peso corporal, administrado a ratas hembras en el 5to día de preñez, sólo causó retardo en el proceso de implantación.

Análises histoquímica e morfométrica de lesões endometrióticas induzidas em ratas e tratadas com dexametasona / Histochemical and morphometric analysis of endometriotic lesions induced in female rats and treated with dexamethasone

INTRODUÇÃO: A literatura relata que os implantes endometriais possuem receptores para hormônios esteroides, sendo estimulados principalmente pelo estrógeno, e que algumas estratégicas de tratamento têm sido propostas em modelos experimentais, tais como a utilização de glicocorticoides sintéticos, como a dexametasona. OBJETIVO: analisar histoquímica e morfometricamente lesões endometrióticas induzidas em ratas e tratadas com 0,8 mg/kg/dia de dexametasona. MATERIAL E MÉTODOS: Quarenta ratas albinas (linhagem Wistar) com 90 dias de vida, pesando aproximadamente 150 g, foram induzidas à endometriose e divididas em grupos: 1. ratas com endometriose e avaliadas após 34 dias (G1); 2. ratas com endometriose e avaliadas após 47 dias (G2); 3. ratas com endometriose e, após 21 dias do pós-operatório, tratadas com dexametasona por 13 dias (G3) e 4. ratas com endometriose e, após 21 dias do pós-operatório, tratadas com dexametasona por 13 dias e eutanasiadas após um período de 13 dias, contados a partir do término do tratamento com dexametasona (G4). Os fragmentos dos implantes endometriais foram fixados em Bouin, incluídos em paraplast e corados por hematoxilina-eosina e tricrômico de Mallory. As médias do número de glândulas foram submetidas ao teste não-paramétrico de Tukey-Kramer (p < 0,05). RESULTADOS: A dexametasona reduziu a inflamação nos implantes endometriais, o teor de colágeno no estroma e significativamente a área ocupada pelas glândulas (G1= 123,25 ± 6,44ª; G2= 113 ± 6,27ª; G3= 81,66 ± 3,05b; e G4= 94 ± 6,24b). CONCLUSÃO: A dexametasona, na dosagem utilizada, reduz os efeitos estrogênicos em implantes endometriais em ratas.

INTRODUCTION: The literature reports that endometrial implants have receptors for steroid hormones primarily stimulated by estrogen and that some treatment strategies have been proposed in experimental models such as the use of synthetic glucocorticoids, for example, dexamethasone. OBJECTIVE: to analyze histochemically and morphometrically endometriotic lesions induced in rats and treated with dexamethasone (0.8 mg/kg/day). MATERIAL AND METHODS: Forty albino female rats (Wistar strain), with 90 days of age, weighing approximately 150 g, were induced with endometriosis and divided into groups: I - rats with endometriosis and evaluated after 34 days, II - rats with endometriosis and evaluated after 47 days, III - rats with endometriosis and 21 days post-surgery treated with dexamethasone for 13 days and IV - rats with endometriosis and 21 days post-surgery treated with dexamethasone for 13 days and euthanized after a period of 13 days starting from the end of treatment. The fragments of endometrial implants were fixed in Bouin, embedded in Paraplast and stained with hematoxylin-eosin and Mallory trichrome. The mean number of glands was compared through nonparametric Tukey-Kramer test (p < 0,05). RESULTS: Dexamethasone reduced inflammation in the endometrial implants, the collagen content in the stroma and decreased significantly the area occupied by glands (GI - 123.25 ± 6.44ª; IGI - 113 ± 6.27ª; GIII - 81.66 ± 3.05b and GIV - 94 ± 6.24b). CONCLUSION: The applied dexamethasone dosage reduces estrogenic effects in endometrial implants in rats.

Análise histológica do ovário de ratas submetidas à ausência de luz / histological analysis of the ovary of female rats submitted to light absence

Objetivo: Obter informações da histologia e do desenvolvimento dos folículos ovarianos de ratas mantidas na ausência de luz. Material e Métodos: Foram utilizadas 10 ratas albinas, as quais foram divididas em dois grupos de cinco animais: GRUPO I - ratas mantidas no ciclo claro/escuro 12/12h, por três meses (Controle), e GRUPO II - ratas mantidas na ausência de luz por três meses. Resultados: Nos animais do grupo II foi observado, na região cortical aos ovários, predominância de corpos lúteos e alguns folículos ovarianos em fase inicial de desenvolvimento, enquanto que na região medular foram evidenciadas poucas células intersticiais dispersas no estroma ovariano. Conclusão: A ausência de luz pode acarretar um aumento do nível de melatonina circulante no sangue e consequentemente, parece contribuir para a manutenção de corpos lúteos e diminuir a atividade de síntese de esteróides das células intersticiais do ovário.

Objective: This study had the objective of acquiring information about the histology and development of ovarian follicles of female rats kept in the absence of light. Material and Methods: 10 albino female rats were used and divided into two groups of five: GROUP I - Female rats kept in the dark-light cycle 12/12 hours, for three months (Control), and GROUP II - female rats kept in the absence of light for three months. Results: in the rats of group II, a predominance of corpus luteum and some ovarian follicles in the initial phase of development was observed in the cortical area to the ovaries, while few dispersed interstitial cells were evidenced in the ovarian stroma, in the medullar area. Conclusion: The absence of light can bring about an increase in the level of melatonin in the blood and consequently, it can contribute to the maintenance of corpus luteum and reduce the activity of synthesis of steroids present in the interstitial cells of the ovary.

Morphometric analysis of the development of the ovarian follicles in pinealectomized rats

El estudio tuvo como objetivo analizar morfometricamente el area ocupada por los foliculos ováricos en ovarios de ratas pinealectomizadas. Para ello, 24 ratas albinas (Rattus norvegicus albinus), fueron divididas igualmente en los siguientes grupos: Grupo I - Ratas falsamente pinealectomizadas y mantenidas en el ciclo claro/oscuro (12/12 horas), por tres meses; Grupo II - ratas pinealectomizadas y mantenidas en el ciclo claro/oscuro (12/12 horas), por tres meses; Grupo III - ratas pinealectomizadas y mantenidas en la ausencia de luz durante tres meses; Grupo IV í ratas falsamente pinealectomizadas, y mantenidas en la ausencia de luz por tres meses. Los resultados mostraron que los grupos I y IV presentaban, respectivamente, medias de 19,00 y 25,00, mientras que los grupos II y III presentaron las mayores medias, 28,25 y 27,25, respectivamente, indicando mayor área ocupada por los folículos. Fue observada una peque¤a cantidad de cuerpos lúteos en los grupos pinealectomizados. De esta manera, concluimos que la pinealectomía puede ejercer, con el tiempo, alguna influencia en la función gonadal, lo que podrá inducir la formación de un cuadro clinico anovulatorio, y consecuentemente, el desarrollo de ovarios policísticos.

Evaluation of the implantation in pinealectomized and/or submitted to the constant illumination rats

En este trabajo evaluamos los aspectos morfológicos y cuantitativos de los sitios de implantaciones en úteros de ratas pinealectomizadas y/o sometidas a iluminación constante. Los grupos experimentales fueron: I í ratas normales mantenidas en ciclo claro / oscuro de 12/12 horas, durante dos meses, cruzadas y sacrificadass en el 60 día de pre¤ez (control); II í ratas sham-pinealectomizadas mantenidas en ciclo claro/oscuro de 12/12 horas, durante dos meses, cruzadas y sacrificadas en el 60 día de pre¤ez (control); III í ratas pinealectomizadas mantenidas en ciclo claro/oscuro de 12/12 horas, durante dos meses, cruzadas y sacrificadas en el 60 día de pre¤ez; IV í ratas normales mantenidas en constante iluminación durante dos meses acasaladas y sacrificadas en el 60 día de pre¤ez; V í ratas sham-pinealectomiazadas mantenidas en constante iluminación durante dos meses, cruzadas y sacrificadas en el 60 día de pre¤ez; VI í ratas pinealectomizadas, mantenidas en constante iluminación durante dos meses, cruzadas y sacrificadas en el 60 día de pre¤ez. El análisis estadístico de las medias de los sitios de implantaciones mostró que hubo diferencia significativa, donde los grupos III, IV, V y VI diferían de los grupos I y II, los cuales presentaron las mayores medias. Los grupos III, IV, V y VI no son diferentes entre sí. El análisis morfológico de los sitios en los grupos controles reveló la presencia de peque¤as lagunas conteniendo sangre, además de células trofoblásticas y algunos citrofoblastos poliploides. En los grupos III, IV, V y VI se evidenció lagunas muy desarrolladas en los sitios, con trofoblastos, citrofoblastos con alto grado de poliploidia y sinciciotrofoblastos. Concluimos que la pinealectomía y/o constante iluminación llevan a una reducción del número de blastocistos implantados en ratas, además estimula el desarrollo de los sitios de implantación, indicando así; que la melatonina puede tener importante función en la viabilidad de implantación del blastocisto.

Morphologic aspects of the endometrium, in the estrus phase, of pinealectomized rats

In this paper, it was analyzed morphologically the endometrium of pinealectomized rats, treated or not with melatonin, besides luteinizing hormones levels (LH), stimulating follicle (FSH) and prolactin (PRL). The experimental groups were: I ¡ normal rats, during three months; II ¡ normal rats, during six months; III ¡ pinelalectomized rats evaluated after three months; IV ¡ pinealectomized rats treated with melatonin for three months; V ¡ pinealectomized rats evaluated after six months; VI ¡ pinealectomized rats for three months, and after treated with melatonin for more three months. In the animals from groups III and V, the estrous ciclicity was modified, because beyond the increase in the incidence of the estrus phase, some animals developed a persistent estrus condition. In the other groups the estrous cycle was normal. The hormonal dosage showed that there was an increase in the LH levels in groups III and V, and a small reduction in group IV. There weren't changes between groups VI and II. The levels of FSH and PRL showed themselves reduced in all animals from the pinealectomized group. However, these results didn't show statistically meaningful differences. In groups III, V and VI the endometrium presented a normal aspect except by the presence of several endometrial glands, in most cases, dilated. In the animals that developed persistent estrus, it was observed a very fibrous stroma and rare endometrial glands, some of them presenting non-keratinazed pavement stratified epithelium. The animals in group IV showed a similar endometrium to the control groups. It was concluded that the pinealectomy can draw to the condition of persistent estrus, not producing great variation in the serumal levels of the gonadotrophic hormones, and inducing more effective changes in the glandular epithelium.