RESUMO
In the present study, we set out to determine whether melatonin combined with a high-fat diet during pregnancy and lactation can prevent liver disorders in offspring. Forty rats were divided into four groups: DC - pregnant rats submitted to the standard diet; DC + Mel - pregnant rats submitted to the standard diet combined with melatonin; HFD - pregnant rats submitted to a high-fat diet; HFD + Mel - pregnant rats submitted to a high-fat diet combined with melatonin. Morphophysiological and biochemical parameters were analyzed. Melatonin (5 mg/kg) was administered intraperitoneally. The HFD group offspring showed an increase in AST, ALT, alkaline phosphatase, cholesterol, triglycerides, LDL and glucose levels, and a reduction in HDL and lipase levels. In the liver obseved steatosis, hepatocellular ballooning, increased lobular parenchyma and reduced non-lobular parenchyma, beside reduced liver glycogen and fibrosis. These changes were not observed in the HFD + Mel group. In conclusion, melatonin combined with a high-fat diet preserves the liver architecture and function in the offspring.
Assuntos
Melatonina , Gravidez , Feminino , Ratos , Animais , Melatonina/farmacologia , Dieta Hiperlipídica/efeitos adversos , Fígado , Colesterol , LactaçãoRESUMO
Integrated Pest Management programs do not always prioritize natural enemies when selecting control methods; too often these important pest reducing agents are negatively affected by the action of other methods in agroecosystems. The aim of this research was to evaluate side effects of a bioinsecticide, developed from the mixture of cedar (Cedrus atlantica), eucalyptus (Corymbia citriodora) and lemon grass (Cymbopogon citratus) essential oils (EOs), in a ratio of 1:1:1, on Psyttalia concolor (Szèpligeti) (Hymenoptera: Braconidae) which is a parasitoid of some pests of the Tephritidae family, as Ceratitis capitata. The LD50 of the EOs mixture for C. capitata females was 3.09 µl/g, whereas the LD50 for P. concolor females was 20.45 µl/g which suggests the natural enemy is more tolerant to the EOs mixture. P. concolor parasitized L3 larvae of C. capitata through a voile treated with the mixture of EOs at 1.8% without causing any deleterious effects neither on the percentage of attacked hosts nor on the emergence rate, whereas at the highest concentration tested, 4.8%, decreased both parameters during the 2 first days after treatment. Semi-field assays showed that mixture of EOs was harmless to P. concolor when released 4 h after treatment whereas killed 55 ± 3.9% males and 37.5 ± 1.6% females of C. capitata. The mixture of EOs used jointly with lambda-cyhalothrin or kaolin, both compounds applied against C. capitata in conventional and organic farming, respectively, did not increase the toxicity and/or persistence against the pest.
Assuntos
Insetos/fisiologia , Óleos Voláteis/toxicidade , Controle de Pragas/métodos , Animais , Feminino , MasculinoRESUMO
The present research aimed to elucidate which aspects of immune responses in Diatraea flavipennella are suppressed by the parasitoid Cotesia flavipes, thus, ensuring parasitism success. We investigated the presence of apoptosis in fat body cells through the TUNEL technique. According to the results, reduced levels of nitric oxide and phenoloxidase activity were observed in larvae parasitized for three days, and reduced total number of hemocytes, after three and seven days. An increase in plasmatocytes and decrease in spherulocytes numbers were observed in the differential count on the third day of parasitism. The number of melanized microspheres in parasitized larvae was low and indicated less intense melanization. The ultrastructural analysis confirmed the immunosuppressive effect of C. flavipes on the encapsulation response of D. flavipennella because only the formation of hemocytes capsules, adhered to the microspheres' surface, was evidenced in non-parasitized caterpillars. The effect of parasitism was also recorded on the third day with the presence of hemocytes and apoptosis in fat body cells, including aspects of degeneration in the latter. We concluded that C. flavipes suppresses cellular and humoral immunological responses in D. flavipennella and drastically affects the host's fat tissue.
Assuntos
Interações Hospedeiro-Parasita/imunologia , Himenópteros/fisiologia , Lepidópteros/parasitologia , Animais , Corpo Adiposo/citologia , Feminino , Interações Hospedeiro-Parasita/fisiologia , Himenópteros/classificação , Larva/enzimologia , Larva/parasitologia , Lepidópteros/imunologia , Monofenol Mono-Oxigenase/metabolismo , Óxido Nítrico/análiseRESUMO
This work aimed to evaluate the effects of Metarhizium anisopliae on Diatraea flavipennella and investigate their immune response. Was observed the effect of M. anisopliae against larvae of D. flavipennella sprayed at concentrations of 103, 104, 105 conidia / mL, in which showed differences relative the larval period, extending up to 72.0 days in treatment and 25.0 days in the control. The results for hemocytes revealed that the most frequent cells when sprayed at the concentrations of 103, 105, 107 conidia / mL were the prohemocytes, spherulocytes, plasmatocytes and granulocytes in relation to adipohemocytes and oenocytoids. The level of nitric oxide was different between the control and the concentration 107 spores / mL (24), while the activity of phenoloxidase was similar among treatments in 24 and higher concentration 107 spores / mL (60h). In biochemical profile of hemocytes was a change in carbohydrates, lipids and proteins in response to the fungus. The results indicate that the fungus M. anisopliae can be used in the Integrated Management of D. flavipennella by presenting pathogenicity and interfere with their development even when exposed to small concentrations.
Assuntos
Lepidópteros/microbiologia , Metarhizium/química , Controle Biológico de Vetores/métodos , Esporos Fúngicos/fisiologia , Animais , Hemócitos/microbiologia , Larva/microbiologiaRESUMO
The botanical insecticides, growth regulators, and pyrethroids have an effect on the biology of Spodoptera frugiperda (Smith). However, no emphasis has been given to the effect of these insecticides on embryonic development of insects, in histological level. Thus, this research aimed to examine by light and scanning electron microscopy S. frugiperda eggs and to describe the embryonic development, before and after immersion treatment, using commercial concentrations and lower concentrations than commercial ones, of the compounds lufenuron (Match), azadirachtin (AzaMax), and deltamethrin (Decis-positive control). For light microscopy semithin sections of eggs were used, and for scanning electron microscopy, images of the surface of eggs, treated and untreated with insecticides. The morphological characteristics of S. frugiperda eggs, in general, were similar to those described in the literature for most of the insects in the order Lepidoptera. Spherical eggs slightly flattened at the poles, with chorion, yolk, vitelline membrane, and embryo formation. In both microscopic analysis, we observed that insecticides acted immediately and independent of concentration, resulting absence, or incomplete embryo, presented yolk granules widely dispersed, without vitellophage formation, chorion disintegration, disorganized blastoderm, presenting vacuoles, yolk region with amorphous cells, and formation of completely uncharacterized appendages. Thus, we conclude that the compounds lufenuron and azadirachtin interfere on S. frugiperda embryonic development.
Assuntos
Benzamidas/farmacologia , Inseticidas/farmacologia , Limoninas/farmacologia , Nitrilas/farmacologia , Piretrinas/farmacologia , Spodoptera/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Microscopia Eletrônica de Varredura , Óvulo/citologia , Óvulo/efeitos dos fármacos , Óvulo/crescimento & desenvolvimento , Spodoptera/citologia , Spodoptera/crescimento & desenvolvimentoRESUMO
BACKGROUND AND AIM: Oocyte in vitro maturation (IVM) is an appealing approach for several assisted reproductive technologies and dissecting oocyte maturation. Nonetheless, IVM leads to lower developmental competence and usually relies on undefined, serum-containing media. Therefore, biochemical profiling aimed to explore fluctuations in IVM media content during the acquisition of oocyte developmental competence. MATERIALS AND METHODS: Bovine cumulus-oocyte complexes (COCs) underwent IVM in TCM199 medium with Earle's salts, supplemented with 2.0 mM L-glutamine, 10% fetal bovine serum, antibiotics, and 0.05 IU/mL porcine follicle-stimulating hormone (FSH+) or vehicle control (CTL) medium for 22 h. RESULTS: FSH withdrawal (CTL) diminished several processes associated with the acquisition of oocyte developmental competence, such as reduced cumulus cell expansion, diminished estradiol synthesis (FSH+: 116.0±0.0 pg/mL vs. CTL: 97.6±18.0 pg/mL), and lower oocyte nuclear maturation rate (FSH+: 96.47% vs. CTL: 88.76%). Fresh media formulations (i.e., TCM199 with FSH or vehicle) were indistinguishable under biochemical profiling threshold conditions. Biochemical profiling showed similar total protein and lipid concentrations between groups. Further, total sugar concentrations diminished from fresh media to their post-IVM counterparts, albeit in an FSH-independent manner. Glycogen concentrations remained unaltered after IVM within CTL media, albeit were substantially lower after IVM under FSH+ conditions. CONCLUSION: FSH mediates the consumption of serum-derived glycogen by bovine COCs during IVM and implies that serum-free media should contain increased glucose concentrations to facilitate the acquisition of oocyte developmental competence.
RESUMO
The study evaluated the effects of R-limonene, in sublethal concentration, on the histology, histochemistry, biochemistry, and carbohydrates and proteins levels in the third instar Aedes aegypti larvae. The R-limonene (LC50 of 27 ppm) and control groups were analyzed 12 and 24 h after the beginning of treatments. The midgut of the control larvae was composed of cylindrical and elongated cells with a spherical and central nucleus and regenerative cells with a pyramidal shape. After 12 h of treatment, columnar cells, protuberances, and cytoplasmic vacuolization were found. However, 24 h after treatment, complete disorganization of the epithelium was observed. There was a positive reaction in all treatments for the presence of glycogen. However, the midgut of larvae treated with R-limonene showed higher levels. For the total protein, positive marking occurred in all groups evaluated, with higher levels in treatments and the lowest in control 12 h. The levels of total protein and glycogen increased in the treated larvae compared to the 12 h control. Besides, a reduction in total sugar levels was observed in the treated larvae compared to controls 12 and 24 h, being more evident in the last one. Therefore, these results demonstrate that R-Limonene caused pathological changes in the epithelium of the A. aegypti midgut at histophysiological and biochemical levels.
Assuntos
Aedes , Inseticidas , Limoneno , Animais , Larva , Extratos VegetaisRESUMO
Scorpion envenomation represents an important health problem in many parts of the world, due to the high number and severity of accidents. Recent studies demonstrated that some species can produce venoms with genetic damage potential. Here, we evaluated whether Tityus stigmurus venom causes genetic damage in blood and testicular cells of Swiss mice. We also analyzed the effect of the venom on the number of spermatogenic lineage cells. Five groups of mice received 0.387â¯mg/kg of the venom, intraperitoneally; one group received saline solution (control group). Blood and testicular cells were collected for comet assay and histological analysis at different times after treatment (1, 2, 6, 12, and 48â¯h). Blood was also collected 48â¯h after treatment for the micronucleus test in erythrocytes. Histological analysis was performed by counting cells of the spermatogenic lineages; the nuclear area of elongated spermatocytes was also evaluated. Treatment with the venom induced DNA damage that endured from 1â¯h to 48â¯h, as confirmed by the comet assay. The micronucleus test demonstrated that the venom induced mutations in erythrocytes. The number of spermatogonia and rounded spermatids decreased in some groups; the number of elongated spermatids increased, and their nuclear size decreased 1â¯h after treatment. Genetic damage can be caused directly by the venom, but we suggested that reactive oxygen species that result from inflammatory process caused by the envenomation may have an important role in the DNA damage. Genetic damage and apoptosis may explain the changes in the number of spermatogenic cells. Furthermore, the decrease in nuclear area may result from chromatin loss. Genetic damage in testicular cells, associated with alterations in the number and morphology of spermatogenic cells, can result in reproduction disorders in animals, or humans, stung by T. stigmurus.
Assuntos
Venenos de Escorpião/toxicidade , Escorpiões , Animais , Ensaio Cometa , Dano ao DNA , Humanos , Masculino , Camundongos , TestículoRESUMO
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.
Assuntos
Mariposas , Piper , Monoterpenos Acíclicos , Animais , Desenvolvimento Embrionário , Larva , SpodopteraRESUMO
Among the microorganisms used in biological control, the muscadine fungus Metarhizium anisopliae (Metsch.) Sorok. is produced and formulated world wide aiming to control pests from several agricultural crops. This work evaluated effects of M. anisopliae isolate UFRPE-6 on the fecundity and mortality of Tuta absoluta (Lepidoptera: Gelechiidae) females and the mechanism of infection on eggs. The infection of the females by the fungus did not affect their oviposition and fecundity; however it affected the survival with total and confirmed mortality of 54.2% and 37.14%, respectively. The eggs were treated with suspension at concentration of 10(6)conidia/mL. The analysis under scanning electron microscopy showed that conidia germination and penetration processes in the eggs of T. absoluta started within the period of 6h after the inoculation. Several hyphal bodies were observed from 12h and an intense extrusion of the mycelium covering all the external surface of the eggs 72h after inoculation. Despite its moderate activity in adults, the isolate URPE-6 of M. anisopliae showed promising in the control of T. absoluta due to its pathogenicity and virulence to eggs from this pest.
Assuntos
Lepidópteros/crescimento & desenvolvimento , Lepidópteros/microbiologia , Metarhizium/patogenicidade , Óvulo/ultraestrutura , Controle Biológico de Vetores , Animais , Besouros/microbiologia , Feminino , Fertilidade , Interações Hospedeiro-Patógeno , Larva/microbiologia , Lepidópteros/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óvulo/microbiologia , Reprodução , VirulênciaRESUMO
A natural insecticide developed from the mixture of the essential oils (EOs) of Cymbopogon citratus (DC.) Stapf (Poaceae), Cedrus atlantica (Endl.) Manetti ex Carriére (Pinaceae), and Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson (Myrtaceae) was studied. The mixture of oils caused high mortality (LD50 = 0.018 µl/insect) to the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), a globally important pest, after topical application on adults. Based on the chemical characterization of biopesticide using gas chromatography-mass spectrometry (GC-MS) analysis, many of the constituents had known insecticidal properties (the monoterpenes α-citronellal and E-citral and the sesquiterpernes α-himachalene and ß-himachalene, all at concentrations above 15%). Phytotoxicity tests on orange trees demonstrated that this natural product was harmless when the mixture was applied diluted in water with a surfactant. The mixture of EOs was also harmless (1, IOBC category) to the biological control agent responsible for reducing populations of tephritids, the parasitoid Psyttalia concolor (Hymenoptera: Braconidae), following exposure to treated orange trees in a semifield assay within a greenhouse, but killed 46.2% of C. capitata (Szépligeti) adults after 72 h. Our results suggest that mixture of EOs has potential for use as an adulticide against medfly, although the production price was exceedingly high compared with that of commercial synthetic insecticides. Therefore, we discuss the advantages and disadvantages related to the potential use of this natural insecticide.
Assuntos
Ceratitis capitata , Controle de Insetos , Inseticidas/análise , Óleos Voláteis/química , Animais , Citrus sinensis , Feminino , Dose Letal Mediana , Masculino , VespasRESUMO
Males of the predatory stinkbug, Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae), accomplish long and multiple matings. We hypothesize that this behavior is due to time requirement for spermatozoa production and their transference to the females. Thus, this work investigated the effect of mating status of males and mating duration on spermatozoa transference to the females and the location of spermatozoa in the male reproductive tract during mating. On females, morphological alterations on female spermatheca and associated structures during a mating were investigated. Analyses of male reproductive tract showed presence of spermatozoa in the lumen of vas deferens was independent of mating status (ca. virgin, 0, 12 and 24 h after having a full mating), indicating continuous spermatogenesis which is supported by the absence of a seminal vesicle for spermatozoa storage. Female spermatheca had no changes associated with the duration of mating. However, females exhibited spermathecal elastic duct swelling by 30 min of mating duration. The success of males in filling the female spermatheca with spermatozoa depends on duration of mating. Thus, the results indicate that multiple mating is a requirement for reproductive success in the species by transference of spermatozoa and accessory substances stored in the female spermathecal duct. Likewise, the long mating is a male requirement to transfer materials in appropriate amount to the female but it is not dependent on spermatozoa alone.
Assuntos
Genitália Masculina/fisiologia , Heterópteros/fisiologia , Comportamento Sexual Animal/fisiologia , Espermatogênese/fisiologia , Animais , Feminino , Genitália Feminina/anatomia & histologia , Genitália Feminina/fisiologia , Masculino , Reprodução/fisiologia , Fatores de TempoRESUMO
Spodoptera frugiperda is a major pest in several crops due to its polyphagous habit. Studies on the use of essential oils for pest control have been increasing over the years, presenting itself as a promising alternative with less environmental impact. Chemical profile evaluations of essential oils enable the knowledge and use of major compounds, providing a better understanding of their actions in the life history of insects. Thus, the study evaluated the effects of the major compounds limonene, trans-anethole and the combined effects upon nutrition, reproduction and testicular apoptosis in S. frugiperda. Larvae of third instar were submitted to the LD50 of the compounds by topical contact and 48 h later the amounts of lipids, proteins, total sugar and glycogen were evaluated. The testicular apoptosis was evaluated in the treated larvae after 48 h and the reproductive parameters were evaluated after adult emergence. All treatments reduced the amounts of lipid, protein, total sugar and glycogen when compared to control. The most significant results were obtained by the association of compounds. All treatments reduced the number of eggs, oviposition period and adult longevity when compared to control. There were no changes in the pre-oviposition and post-oviposition periods. Testicular apoptosis was observed in the limonene and in the combined treatments. It is concluded that limonene and trans-anethole, especially in association, cause adverse effects upon nutrition and reproduction in S. frugiperda, altering essential parameters for its survival and establishment on crops.
Assuntos
Anisóis/toxicidade , Cicloexenos/toxicidade , Reprodução/efeitos dos fármacos , Spodoptera/efeitos dos fármacos , Terpenos/toxicidade , Testículo/efeitos dos fármacos , Derivados de Alilbenzenos , Animais , Anisóis/química , Apoptose/efeitos dos fármacos , Cicloexenos/química , Isomerismo , Larva/efeitos dos fármacos , Dose Letal Mediana , Limoneno , Masculino , Microscopia de Fluorescência , Óleos Voláteis/química , Spodoptera/crescimento & desenvolvimento , Terpenos/química , Testículo/citologia , Testículo/metabolismoRESUMO
It was described the morphology and histological composition of the structures related to production, storage and distribution of Bracon vulgaris venom, a wasp that parasite their hosts after the inoculation of a venom which causes irreversible paralysis. Were found 22 glandular filaments, coated with secretory epithelium associated with a reservoir coated internally by a chitin layer and externally by striated muscular fibers. A valve mediates the passage of the toxin to venom duct towards the parasitoids sting.
Assuntos
Venenos de Vespas/metabolismo , Vespas/anatomia & histologia , Animais , Feminino , Venenos de Vespas/análise , Vespas/metabolismoRESUMO
The central nervous system is vulnerable to complications caused by diabetes. These complications lead to increased oxidative stress in the brain, resulting in damage to the cerebral cortex, among other regions. Insulin and hypoglycemic agents are still the most widely used treatments. However, current research with an experimental model of diabetes suggests the use of antioxidants, such as melatonin. Thus, we tested the hypothesis that exogenous melatonin may decrease or prevent the effects of diabetes in the frontal cortex of the rat brain. Fifty albino rats were allocated into five groups: GC = rats without diabetes induction, GD = diabetic rats induced by streptozotocin, GDM = streptozotocin-induced and melatonin-treated diabetic rats, GDI = diabetic rats induced by streptozotocin and treated with insulin, GDMI = diabetic rats induced by streptozotocin and treated with melatonin and insulin simultaneously. Diabetes was induced by intraperitoneal administration of streptozotocin (60mg/kg). Insulin (5U/day) was administered subcutaneously and melatonin (10mg/kg) by drinking water; both treatments last days after. We analyzed animals' weight, the cytokines IL-6 and TNF-α, apoptosis, glycogen, and did morphometry and histopathology of the frontal cortex were analyzed. The results showed that the cerebral cortex of the diabetic animals presented axonal degeneration, reduced number of neurons in the cortex, reduced glycogen, increased IL-6 and TNF-α expression, high apoptotic index, and reduced animal weight and the brain. Treatment with melatonin associated or not with insulin prevented such effects. Thus, we conclude that melatonin associated with insulin may be an alternative for avoiding the impact of diabetes in the brain's frontal cortex.(AU)
O sistema nervoso central é vulnerável a complicações originadas pelo diabetes estresse oxidativo no cérebro e resultando em lesões no córtex cerebral, dentre outras regiões. A insulina e hipoglicemiantes ainda são os tratamentos mais utilizados, entretanto, pesquisas atuais com modelo experimental do diabetes sugerem a utilização de antioxidantes como, por exemplo, a melatonina. Assim, testamos a hipótese de que a melatonina exógena pode diminuir ou prevenir os efeitos do diabetes no córtex frontal do cérebro de ratos. Foram utilizados 50 ratos albinos, divididos em 5 grupos: GC = ratos sem indução ao diabetes, GD = ratos induzidos ao diabetes pela estreptozotocina, GDM = ratos induzidos ao diabetes pela estreptozotocina e tratados com melatonina, GDI = ratos induzidos ao diabetes pela estreptozotocina e tratados com insulina, GDMI = ratos induzidos ao diabetes pela estreptozotocina e tratados com melatonina e insulina simultaneamente. O diabetes foi induzido pela administração intraperitoneal de estreptozotocina (60mg/kg). A insulina (5U/dia) foi administrada por via subcutânea e a melatonina (10mg/kg) pela água de beber. Ambos tratamentos foram realizados durante 30 dias após a indução. Foram analisados o peso dos animais, do cerebro, as citocinas IL-6 e TNF-α, apoptose, glicogênio, além da morfometria e histopatologia do córtex frontal. Os resultados mostraram que o córtex cerebral dos animais diabéticos apresentou degeneração axonal, redução do número de neurônios no córtex, redução do glicogênio, aumento da expressão do IL-6 e TNF-α, elevação do índice apoptótico, além da redução do peso dos animais e do cérebro. O tratamento com melatonina associada ou não a insulina preveniu tais efeitos. Assim, concluímos que a melatonina associada ou não a insulina pode ser uma alternativa na prevenção dos efeitos do diabetes no córtex frontal do cérebro.(AU)
Assuntos
Animais , Ratos , Imuno-Histoquímica , Córtex Cerebral , Melatonina , Ratos/anormalidades , Apoptose , Estresse OxidativoRESUMO
Colon adenocarcinoma is a disease expanding worldwide. Cancer of colon and rectum are among the top ten most insidious types in Brazil. In vitro and in vivo studies have demonstrated the efficacy of the hormone melatonin to prevent and reduce tumor growth. However, there are only few studies addressing the action of melatonin on Caco-2 cells. Thus, the cytotoxic effect of melatonin on the ultrastructure of Caco-2 cells was investigated. The MTT colorimetric method was used to assess the cytotoxicity. A total of 2×10(6)cells/mL were seeded in microplates and incubated at 50, 25, 12.5, 6.25, 3.125, 1.56, 0.78 and 0.0 (control) µg/mL of melatonin. For ultrastructural analysis concentrations with low, medium and high cytotoxicity plus the control were used for ultrastructural analysis. The concentrations 50, 1.56 and 0.78 µg/mL of melatonin showed low, medium and high cytotoxicity, respectively. Ultrastructurally, the control tumor cells were shown to be preserved. Caco-2 cells showed morphological changes at 50 µg/mL of melatonin, with numerous vacuoles, mitochondrial degeneration and reduced glycogen. However, Caco-2 cells also showed altered morphology in treatments at 1.56 and 0.78 µg/mL of melatonin with characteristics of cells in degeneration by the presence of numerous vacuoles, absence of microvilli, mitochondrial degeneration and nuclear fragmentation. Thus, one can infer that concentrations of 1.56 and 0.78 µg/mL of melatonin promote cytotoxicity in Caco-2 cells, which can probably be related to the generation of reactive oxygen species (ROS).
Assuntos
Células CACO-2/efeitos dos fármacos , Células CACO-2/ultraestrutura , Melatonina/farmacologia , Apoptose/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Bats belong to the order Chiroptera, family Phyllostomidae, and present a wide diversity of reproductive strategies. However, information on the reproductive biology of male bats is scarce, mainly in the Northeast Region of Brazil. Thus, this study evaluated the seasonal testicular histomorphometry of the bat Carollia perspicillata in fragments of the Atlantic Forest in Pernambuco state. To this end, adult males were collected, euthanized for removal of the testicles, and later submitted to a routine histological technique. Histomorphometric analysis included assessment of the areas of tubular and intertubular compartment occupation, as well as quantification of spermatocytes, rounded spermatids, elongated spermatids, and Sertoli and Leydig cells. Results indicated that this bat species presents reproductive seasonality, because significantly higher averages of the testicular parameters were observed in the rainy season, which is a period of greater availability of food resources. Such inferences indicate that there is a synchrony between peak spermatogenesis and hormonal inversion in the months of high precipitation; furthermore, a higher carrying capacity of the Sertoli cells is noted. C. perspicillata males possibly present greater sperm and androgenic activity in the rainy season, associated with increased tubular area and number of spermatogenic cells, as well as with the intertubular area and number of Leydig cells, respectively.(AU)
Os morcegos pertencem a ordem Chiroptera, família Phyllostomidae, e apresentam ampla diversidade de estratégias reprodutivas. Entretanto, as informações relacionadas à biologia reprodutiva dos machos são escassas, principalmente no Nordeste do Brasil. Dessa forma, o trabalho avaliou a histomorfometria sazonal testicular de Carollia perspicillata em fragmentos de Mata Atlântica de Pernambuco. Para tanto, os machos adultos foram coletados, eutanasiados para a remoção dos testículos, e posteriormente submetidos à técnica histológica de rotina. As análises histomorfométricas avaliaram as áreas de ocupação do compartimento tubular e intertubular, assim como a quantificação dos espermatócitos, espermátides arredondadas, espermátides alongadas, células de Sertoli e de Leydig. Os resultados indicaram que a espécie apresenta sazonalidade reprodutiva, visto que maiores médias significativas dos parâmetros testiculares foram encontradas na estação chuvosa, que é um período de maior disponibilidade de recursos alimentares. Tais inferências indicam que existe uma sincronia entre o pico de espermatogênese e investimento hormonal nos meses de alta precipitação, atrelado a isso, nota-se ainda, uma maior capacidade de suporte das células de Sertoli. Os machos de C. perspicillata possivelmente apresentam uma maior atividade espermática e androgênica na estação chuvosa, associadas ao aumento da área tubular e do número de células espermatogênicas, assim como da área intertubular e do número das células de Leydig, respectivamente.(AU)
Assuntos
Animais , Estações do Ano , Quirópteros/anatomia & histologia , Quirópteros/fisiologiaRESUMO
AIMS: One of the models used for studying cancer is the Ehrlich ascites tumor (EAT) due to its ability to grow in liquid suspension, allowing a standard number of cells to be inoculated, growth quantification and regression of tumor mass. Among the oncostatic substances, melatonin has shown effectiveness in limiting the tumor cell proliferation. However, studies have shown contradictory effects of melatonin on the EAT. This study has investigated the melatonin effect on tumor growth, time and survival percentage, ultrastructure and metastasis of EAT cells in mice submitted or not to pinealectomy. MAIN METHODS: Animals were inoculated with 5×106 cells/mL and treated or not with exogenous melatonin with doses of at 150 and 300 µg/30 g animal weight for 12 days. Melatonin significantly reduced the abdominal circumference, volume of ascites liquid and EAT-cell viability, raising rates of time and mice survival percentage. KEY FINDINGS: Ultrastructurally, the melatonin treatment revealed changes in the shape of cells, the cell surface showed numerous projections, some bifurcated, cytoplasmic vacuolation, mitochondrial degeneration and nuclear fragmentation, peculiar characteristics of apoptosis. Histopathology revealed no metastasis in the liver, small intestine and large intestine in any of the animals in the experimental groups; however this process was evident in the lungs and kidneys, being inhibited by melatonin administration. SIGNIFICANCE: Thus,we can conclude that doses of 150 and 300µg/30g of melatonin for 12 consecutive days have a very effective oncostatic and cytotoxic activity on EAT cells in mice.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Ehrlich/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Melatonina/farmacologia , Animais , Antineoplásicos/administração & dosagem , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Carcinoma de Ehrlich/patologia , Carcinoma de Ehrlich/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Melatonina/administração & dosagem , Camundongos , Metástase Neoplásica , Glândula Pineal/cirurgia , Taxa de SobrevidaRESUMO
Products with Bacillus thuringiensis (Bt) and synthetic insecticides have been widely used against important vectors of human diseases. However, few studies have addressed the application of these substances on the female reproduction apparatus during pregnancy at doses that do not cause clinical symptoms of intoxication. Seventy pregnant albino rats were analyzed with regard to fertility and histopathology of the kidneys, liver and lungs as well as the morphology of the neonates. The rats were submitted to three sub-lethal doses of the biological insecticide XenTari(®) WG (B. thuringiensis subsp. Aizawai) and the synthetic insecticide deltamethrin (Decis(®) 25CE). After the confirmation of copulation, the insecticides were administered orally for either seven days or during the entire pregnancy. The analysis revealed histopathological alterations in all organs analyzed in both treatments. No miscarriages occurred and the neonates did not exhibit signs of malformation of the head, limbs, thorax or abdomen. However, there were a smaller number of pups in the groups that received higher doses of the insecticides in comparison to the control group. Both insecticides produced similar lesions in the kidneys, liver and lungs and reduced the fertility of rats when administered at sub-lethal doses with no clinical signs of intoxication. Thus, this study suggests that sublethal doses of both insecticides can provide chronic toxicity in humans.
Assuntos
Toxinas Bacterianas/toxicidade , Fertilidade/efeitos dos fármacos , Inseticidas/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nitrilas/toxicidade , Precursores de Proteínas/toxicidade , Piretrinas/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Rim/patologia , Fígado/patologia , Pulmão/patologia , Especificidade de Órgãos , Gravidez , Ratos , Ratos WistarRESUMO
This study aimed to analyze the reproductive stage, histology and morphometry of the ovary of Dermanura cinerea in an Atlantic Forest fragments in the Biological Reserve of Saltinho, Pernambuco, Brazil. Adult females were captured monthly by mist net, during two consecutive nights from June/2014 to November/2015. The meteorological data were provided by the National Institute of Meteorology and grouped together with the reproductive data, in six periods: period I (June to August/2014), period II (September to November/2014), period III (December/2014 to February/2015), period IV (March to May/2015), period V (June to August/2015) and period VI (September to November/2015). The females were classified according to their reproductive stages in: Inactive, pregnant, lactating and postlactating. Among the 25 females caught, 10 inactive females were selected for the histomorphometric analysis of the ovaries and then they were euthanized. After that, the specimens had their ovaries removed, fixed, processed and included in Paraplast. The organs were cut and stained by Hematoxylin - Eosin and the histological slides produced were submitted to the appropriate optical microscope analysis. Each type of ovarian follicle was estimated according to the histological characteristics evidenced for other mammals. In the morphometric analysis, it was considered: The area of the ovary (measured in square millimeter), Quantification of different types of ovarian follicles (unilaminar and multilaminar primary follicles, antral and matures) and corpus luteum, as well as the area of each by those different follicles (measured in square micrometer) The results indicated that 16 females were inactive, 5 were lactating, 4 were pregnant and no post-lactating. The histological analysis revealed that the ovaries of D. cinerea exhibit characteristics, structures and cellular types similar to other mammals. The morphometric data of the study area were statistically evaluated using the Student's t-test. Therefore, ovarian histomorphometric analysis are very important to infer with greater certainty about the reproduction of a species. Thus, it was observed that females of D. cinerea exhibit two reproductive peaks, that is, they can give birth either at the end of dry periods or from the beginning to the middle of the rainy season. The main feature observed in the ovary of this species, found in the Atlantic Forest area of the state of Pernambuco, is the preparation of the ovarian cortex to ovulate in months of high rainfall throughout the year. Therefore, this species tries to adjust its reproductive period with the variations of the environmental conditions, so that the reproduction might occur during the period more favorable for the maintenance of their offspring.(AU)
Esse estudo objetivou analisar o estágio reprodutivo, histologia e morfometria do ovário de Dermanura cinerea em um fragmento de Mata Atlântica da Reserva Biológica de Saltinho (Pernambuco, Brasil). Foram utilizadas fêmeas adultas capturadas por redes de neblina, de modo que as coletas ocorreram mensalmente, durante duas noites consecutivas de Junho/2014 a Novembro/2015. Os dados meteorológicos foram fornecidos pelo Instituto Nacional de Meteorologia e agrupados, juntamente com os dados reprodutivos, em seis períodos, sendo estes: período I (Junho a agosto/2014), período II (Setembro a novembro/2014), período III (Dezembro/2014 a fevereiro/2015) período IV (Março a maio/2015), período V (Junho a agosto/2015) e período VI (Setembro a novembro/2015). As fêmeas foram classificadas, de acordo com o estágio reprodutivo em: inativas, grávidas, lactantes e pós-lactantes. Das 25 fêmeas capturadas, foram selecionadas, para as análises histomorfométricas dos ovários, 10 fêmeas inativas, as quais foram eutanasiadas. Depois disso, os espécimes tiveram os seus ovários removidos, fixados, processados e inclusos em paraplast. Os cortes foram corados por Hematoxilina - Eosina e as lâminas histológicas produzidas foram submetidas às devidas análises em microscópio óptico. Cada tipo de folículo ovariano foi estimado de acordo com as características histológicas evidenciadas para outros mamíferos. Nas análises morfométricas, considerou-se: a área do ovário (mensurada em milímetro quadrado), quantificação dos diferentes tipos de folículos ovarianos (primários unilaminar e multilaminar, antrais e maduros) e corpo lúteo, bem como foi medida a área de cada um desses diferentes tipos de folículos (mensurada em micrômetro quadrado). Os resultados indicaram a presença de 16 fêmeas inativas, 5 lactantes, 4 grávidas e nenhuma pós-lactante. As análises histológicas destacaram que os ovários de D. cinerea possui características, estruturas e tipos celulares padrões semelhantes ao dos demais mamíferos. Os dados morfométricos da área do ovário foram avaliados estatisticamente por meio do teste t de Student. Assim, as análises histomorfométricas ovariana são de suma importância para inferir com maior segurança sobre a reprodução de uma dada espécie. Portanto, ficou constatado que as fêmeas de D. cinerea apresentam dois picos reprodutivos, isto é, podem parir no final de períodos secos ou do início para metade do período chuvoso. A principal característica observada no ovário dessa espécie, encontrada em área de Mata Atlântica do estado de Pernambuco, foi a preparação do córtex ovariano para ovular em meses de elevados índices pluviométricos ao longo do ano. Logo, essa espécie procura ajustar seu período reprodutivo com as variações das condições ambientais, de forma que a reprodução ocorra em períodos mais favoráveis para manutenção da prole.(AU)