Disfunção cognitiva canina: tratamentos disponíveis / Canine cognitive dysfunction: Available treatments

A disfunção cognitiva canina (DCC) é uma enfermidade que causa alterações fisiológicas e comportamentais em cães idosos, e que apresenta uma fisiopatogenia semelhante à doença de Alzheimer (DA), que acomete seres humanos. Os sinais clínicos são representados pela sigla DISHA (desorientação, mudanças na interação com pessoas/animais, alterações no ciclo sono-vigília, falha no aprendizado/memória e nível de atividades alteradas). A principal forma de diagnóstico da doença é baseada em um questionário respondido pelo tutor, relacionado ao comportamento do animal. O tratamento é multimodal, consistindo basicamente em uso de fármacos, mudanças na alimentação, e enriquecimento ambiental e mental. Os fármacos utilizados são de diversas classes farmacológicas e agem diretamente em substâncias relacionadas com a fisiopatogenia da DCC, além de atenuarem alguns sinais clínicos da enfermidade. Essa ação dos fármacos é potencializada com a adição de alimentos específicos, enriquecimento do ambiente que o animal vive e estimulação mental, principalmente por meio de passeios. A união de todas essas modalidades de tratamento auxilia na melhoria do bem-estar do animal acometido. Como a disfunção não tem cura, o tratamento é longo e, muitas vezes, não é possível visualizar melhora evidente no animal. Dessa forma, alguns tutores acabam optando pela eutanásia. Apesar de ser frequente em cães idosos e haver uma ampla base literária acerca da DCC, não há um protocolo terapêutico específico. Sendo assim, há diversos tratamentos disponibilizados de forma isolada na literatura, fazendo com que os clínicos veterinários encontrem dificuldades para achar um compilado de informações em uma única fonte.

Canine cognitive dysfunction (CCD) is a disease that causes physiological and behavioral changes in elderly dogs and presents a physiopathogeny similar to Alzheimer's disease (AD), which affects humans. Clinical signs are represented by the acronym DISHA (disorientation, changes in interaction with people/animals, changes in the sleep-wake cycle, learning/memory failure, and altered activity level). The main form of diagnosis of illness is based on a questionnaire answered by the tutor, related to the animal behavior. The treatment is multimodal, basically consisting of drug use, changes in the diet, and environmental and mental enrichment. The drugs used are of various pharmacological classes and act directly on substances related to the physiopathogeny of CCD, besides attenuating some clinical signs of the disease. This drug action is enhanced with the addition of specific foods, enrichment of the environment where the animal lives and mental stimulation, mainly through tours. The union of all these treatment modalities helps to improve the welfare of the affected animal. As the disease has no cure, the treatment is long and it is often not possible to visualize evident improvement in the animal. In this way, some tutors opt for euthanasia. Despite being frequent in elderly dogs and there is a broad literature on CCD, there is no specific therapeutic protocol. There are several treatments available in isolation in the literature, causing veterinary clinicians find it difficult to locate a compilation of information from a single source.

Cinomose em canídeos silvestres no Brasil / Distemper in wild canids in Brazil

A cinomose é uma doença viral multissistêmica causada por um Morbillivirus. No Brasil, existem seis espécies de canídeos silvestres vulneráveis a essa enfermidade. Dessa forma, este trabalho tem como objetivo apresentar uma revisão sobre a situação da cinomose em canídeos silvestres no Brasil e os impactos causados na fauna brasileira. A transmissão do vírus ocorre através do contato com amostras contaminadas, a exemplo dos aerossóis, excretas e secreções de indivíduos infectados. Os sinais clínicos mais prevalentes são de ordem neurológica, entretanto, também podem ser identificadas manifestações respiratórias, cutâneas e gastrointestinais. Portanto, o diagnóstico consiste na avaliação da sintomatologia apresentada em conjunto com testes específicos, como isolamento viral, ELISA, imunofluorescência e RT-PCR. Atualmente, não existe tratamento específico. Desta forma, são realizados apenas cuidados paliativos. Os grandes carnívoros são os mamíferos mais ameaçados do mundo, sobretudo, em consequência dos impactos causados pela redução do habitat natural, associada à expansão territorial humana. As epidemias também justificam as altas taxas de mortalidades desses animais, o que pode estar relacionado com comportamentos sociais e de farejamento, assim como o crescente contato entre animais silvestres e domésticos devido à urbanização e à proximidade genética que os canídeos silvestres têm com os cães domésticos, tornando-os suscetíveis às infecções. Visto que a cinomose é uma patologia emergente em populações de carnívoros silvestres e que a presença de cães domésticos não vacinados em áreas de conservação representa um grande risco de contaminação, conclui-se que a não vacinação está diretamente associada à perpetuação do vírus no meio selvagem.

Distemper is a multisystem viral disease caused by a Morbillivirus. In Brazil, there are six species of wild canids, vulnerable to this disease. Therefore, the present work aims to develop a review on the situation of distemper in wild canids in Brazil and the impacts caused on the Brazilian fauna. The virus transmission occurs through contact with contaminated samples, such as aerosols, excreta, and secretions from infected individuals. The most prevalent clinical signs are neurological; however, respiratory, cutaneous and gastrointestinal manifestations can also be identified. Thus, the diagnosis consists of evaluating the symptoms presented together with specific tests, such as viral isolation, ELISA, immunofluorescence, and RT-PCR. Currently, there is no specific treatment. Therefore, only palliative care is performed. Large carnivores are the most threatened mammals in the world, mainly as a result of the impacts caused by the reduction of natural habitat, associated with human territorial expansion. Epidemics also justify the high mortality rates of these animals, which may be related to social and sniffing behaviors, as well as the increasing contact between wild and domestic animals due to urbanization and the genetic proximity that wild canids have with domestic dogs, making them susceptible to infections. Since distemper is an emerging pathology in populations of wild carnivores and the presence of unvaccinated domestic dogs in conservation areas represents a great risk of contamination, it is concluded that non-vaccination is directly associated with the perpetuation of the virus in the wild.

Síndrome da asfixia perinatal em potros / Perinatal asphyxia syndrome in foals

A neonatologia equina é um ramo crescente nos mercados veterinário brasileiro e mundial. Dentre as afecções que acometem o potro neonato, destaca-se a síndrome da asfixia perinatal, a qual é caracterizada por alterações neurológicas e comportamentais. Essa síndrome acomete o neonato desde o terço final da gestação até os 30 primeiros dias de vida. Apesar de ser descrita há décadas na literatura, esta síndrome ainda se caracteriza como um problema atual com relevante prevalência de óbitos. Tal ocorrência é, muitas vezes, devido à demora do diagnóstico e a falta de conhecimento agregado acerca de novos tratamentos mais efetivos, assim como tratamentos tradicionais de suporte. Assim, este trabalho teve como objetivo entender como ocorre à síndrome da asfixia perinatal em potros, identificar os sinais clínicos característicos, abordar tratamentos e divulgar informações que auxiliem na redução das taxas de óbito e de eutanásia dos potros acometidos. Para tal, o trabalho foi desenvolvido com base na revisão bibliográfica integrativa de literatura. O levantamento bibliográfico foi realizado por meio de consulta em base de dados, como Scielo, Google Acadêmico, Portal de Periódicos CAPES e PUBVET, tomando como referência, principalmente, a consulta à Biblioteca Virtual em Medicina Veterinária e Zootecnia (BVS Vet). O trabalho ainda focou na importância de agregar os tratamentos convencionais de suporte ao método alternativo de compressão, na intenção de elevar os índices de sucesso clínico dos potros neonatos acometidos e diminuir as ocorrências de eutanásias, comumente associadas ao alto custo médico aplicado ao animal acometido pela síndrome da asfixia perinatal.

Equine neonatology is an increasing segment in the Brazilian and global veterinary market. Among the disorders that affect the newborn foal, the perinatal asphyxia syndrome, which is characterized by neurological and behavioral changes, stands out. This syndrome affects the newborn from the last third of pregnancy until the first 30 days of life. Despite being described in the literature for decades, the syndrome is still characterized as a current problem with a relevant prevalence of deaths. This occurrence is, often, due to diagnostic delay and lack of aggregated knowledge about new and more effective treatments, as well as traditional supportive treatments. Thus, this study aimed to understand how perinatal asphyxia syndrome occurs in foals, identify the characteristical clinical signs, discuss treatments, and disseminate information that helps reduce the death and euthanasia rates of affected foals. For this purpose, this study was developed based on an integrative literature review. The bibliographic survey was carried out by consulting a database such as Scielo, Google Academic, Periodical's portal CAPES, and PUBVET, referring mainly to the consultation of the Virtual Library in Veterinary Medicine and Animal Science (BVS Vet). The work also focused on the importance of adding the supporting conventional treatments to the alternative squeeze method, intending to increase the clinical success rates of affected newborn foals and reduce the occurrence of euthanasia, commonly associated with the high medical care cost applied to the animal affected by perinatal asphyxia syndrome.

Qualitative and quantitative aspects of atresia during mammalian folliculogenesis / Aspectos qualitativos e quantitativos da atresia durante a foliculogênese em mamíferos

Durante a foliculogênese ovariana, cerca de 99,9% dos folículos morrem pelo processo de atresia folicular. O processo de atresia pode ocorrer pelas vias degenerativa ou apoptótica. Este processo compromete todos os estágios de desenvolvimento folicular, sendo os folículos antrais os mais afetados. Por outro lado, os folículos préantrais são mais resistentes, em função de sua menor taxa metabólica, bem como do número reduzido de células e camadas de células somáticas, células da granulosa e/ou da teca. Embora folículos pré-antrais sejam menos afetados pelo processo de atresia, quando este evento ocorre, pode-se classificá-lo de duas formas, degeneração do tipo I e degeneração do tipo II. Na degeneração do tipo I, o oócito é o compartimento mais comprometido, apresentando núcleo picnótico, embora suas células da granulosa apresentem-se bem organizadas e sem picnose nuclear. Já na degeneração do tipo II, os folículos apresentam oócito retraído e células da granulosa edemaciadas, desorganizadas e sem aderência à membrana basal e ao oócito. É importante destacar que a degeneração do tipo I é mais comum em folículos primordiais e primários, enquanto folículos secundários apresentam mais degeneração do tipo II, ou seja, a medida que os folículos evoluem, a degeneração do tipo II é mais frequente. Considerando todos os aspectos aqui relacionados, essa revisão de literatura abordará aspectos relacionados aos processos de foliculogênese e atresia folicular, bem como as substâncias que induzem a atresia durante a foliculogenese in vitro e in vivo e, ainda, os métodos e parâmetros para análise da atresia em folículos ovarianos. Isto se deve a necessidade de desenvolvimento de protocolos mais eficientes de recuperação dos folículos ovarianos, prevenindo essa grande perda folicular e otimizando as possibilidades de utilização desses materiais biológicos no futuro.

During ovarian foliculogenesis, about 99.9% of follicles die by the follicle atresia process. The atresia process can occur via degeneration or apoptosis. This process compromises all the follicle development stages, with antral follicles being those most affected. On the other hand, the preantral follicles are more residents, since their slow metabolic rate, as well as the reduced number and layers of somatic cells, granulosa and/or thecal cells. Although preantral follicles are less affected by the atresia process, when the event occurs, we can classify it in two ways, type I or type II degenerated follicles. In the type I degeneration the oocyte is the most compromised compartment, showing the picnotic nuclei, although its granulosa cells presented well organized and no picnosis. Already in the type II degeneration, the follicles presented shrunken in the oocyte, and swollen, disorganization and no adhered granulosa cells from the basal membrane and oocyte. It is important to highlight that type I degeneration is the most common in primordial and primary follicles, while in secondary follicles present more type II degeneration, which means that the as follicle evolve, type II degeneration is more frequent. Considering all the aspects related here, this literature review will address aspects related to the folliculogenesis and the process of follicle atresia, as well as substances that induce atresia during in vitro and in vivo folliculogenesis and methods and parameters for analyzing atresia in ovarian follicles. This is due to the need to develop more efficient ovarian follicle recovery protocols, which can prevent this great follicular loss and optimizing the possibilities of use of these biological materials in the future.

Sarna psorótica em equino / Psoroptic scabies in equine

This study was carried out on a horse with 3-year-old, male of the Paint horse breed, suffering from psoroptic scabies. The animal presented dermatological symptomatology characterized by areas of alopecia, with edema, intense pruritus and bleeding. The dorsal and face regions was the most affected area of the body. The diagnosis was made based on the animal's anamnesis, epidemiological information, clinical history and skin scrapings, through the microscopic visualization of the adult forms of Psoroptes spp. The therapeutic course was performed through topical and environmental treatment, with proved effective. Psoroptic mange is caused by Psoroptes spp., a mite that can parasitize horses, cattle, sheep and goats. Information available in the literature related to the occurrence of psoroptic scabies in horses is scarce. This case report aims to describe the occurrence of this disease in an equine in the state of Ceará.

Sarna psorótica em equino / Psoroptic scabies in equine

This study was carried out on a horse with 3-year-old, male of the Paint horse breed, suffering from psoroptic scabies. The animal presented dermatological symptomatology characterized by areas of alopecia, with edema, intense pruritus and bleeding. The dorsal and face regions was the most affected area of the body. The diagnosis was made based on the animal's anamnesis, epidemiological information, clinical history and skin scrapings, through the microscopic visualization of the adult forms of Psoroptes spp. The therapeutic course was performed through topical and environmental treatment, with proved effective. Psoroptic mange is caused by Psoroptes spp., a mite that can parasitize horses, cattle, sheep and goats. Information available in the literature related to the occurrence of psoroptic scabies in horses is scarce. This case report aims to describe the occurrence of this disease in an equine in the state of Ceará.(AU)

Achados anatomopatológicos em serpente Boa constrictor vítima de atropelamento / Anatomopathological findings in snake Boa constrictor victim of run over

Acidentes automobilísticos em animais silvestres são cada vez mais comuns. Isso acontece devido ao aparecimento desses animais em áreas urbanas, como consequência da perda de seu habitat natural, que sofre influências do homem, como o desmatamento e o uso econômico dessas áreas. O presente relato descreve o caso de uma jiboia (Boa constrictor) de vida livre, vítima de atropelamento, e seus achados anatomopatológicos decorrentes do acidente. Na necropsia foi observado na região lateral uma laceração na pele de aproximadamente 6 cm de comprimento. Além disso, havia evisceração de segmento de alças intestinais. No subcutâneo e na musculatura evidenciou-se áreas multifocais de hemorragia, e as costelas estavam fraturadas. Ressalta-se a importância da preservação dessas espécies, através de medidas que minimizem as chances de ocorrência de acidentes causados pelo homem, que repercutem na queda da biodiversidade.

Automobile accidents in wild animals are becoming more common. This is due to the appearance of these animals in urban areas as a consequence of the loss of their natural habitat, which is influenced by human, such as deforestation and the economic use of these areas. The present report describes the case of a jiboia (Boa constrictor) victim of trampling and his anatomopathological findings resulting from the accident. At the necropsy a laceration in the skin of approximately 6 cm in length was observed in the lateral region. In addition, there was evisceration of segment of intestinal loops. In the subcutaneous and in the musculature multifocal areas of hemorrhage were evidenced, and the ribs were fractured. The importance of the preservation of these species is emphasized through measures that minimize the chances of human-induced accidents, which affect the decline of biodiversity.

Achados anatomopatológicos em serpente Boa constrictor vítima de atropelamento / Anatomopathological findings in snake Boa constrictor victim of run over

Acidentes automobilísticos em animais silvestres são cada vez mais comuns. Isso acontece devido ao aparecimento desses animais em áreas urbanas, como consequência da perda de seu habitat natural, que sofre influências do homem, como o desmatamento e o uso econômico dessas áreas. O presente relato descreve o caso de uma jiboia (Boa constrictor) de vida livre, vítima de atropelamento, e seus achados anatomopatológicos decorrentes do acidente. Na necropsia foi observado na região lateral uma laceração na pele de aproximadamente 6 cm de comprimento. Além disso, havia evisceração de segmento de alças intestinais. No subcutâneo e na musculatura evidenciou-se áreas multifocais de hemorragia, e as costelas estavam fraturadas. Ressalta-se a importância da preservação dessas espécies, através de medidas que minimizem as chances de ocorrência de acidentes causados pelo homem, que repercutem na queda da biodiversidade.(AU)

Automobile accidents in wild animals are becoming more common. This is due to the appearance of these animals in urban areas as a consequence of the loss of their natural habitat, which is influenced by human, such as deforestation and the economic use of these areas. The present report describes the case of a jiboia (Boa constrictor) victim of trampling and his anatomopathological findings resulting from the accident. At the necropsy a laceration in the skin of approximately 6 cm in length was observed in the lateral region. In addition, there was evisceration of segment of intestinal loops. In the subcutaneous and in the musculature multifocal areas of hemorrhage were evidenced, and the ribs were fractured. The importance of the preservation of these species is emphasized through measures that minimize the chances of human-induced accidents, which affect the decline of biodiversity.(AU)

Role of Insulin-like growth factor-I (IGF-I) and Kit Ligand (KL) in ovarian function / Papel do fator de crescimento semelhante à Insulina-I (IGF-I) e Kit Ligand (KL) na função ovariana

Background: The ovarian function is coordinated by many growth factors and hormones responsible for ensuring the success of follicular and oocyte development. To obtain competent oocytes is necessary to have a perfect interaction between follicular somatic cells and the oocyte, which is potentially regulated by paracrine factors produced in the ovary. Among these factors, we highlight the insulin-like growth factor-I (IGF-I) and Kit ligand (KL). This review summarizes the main aspects of molecular structure of IGF-I and KL and their receptors, the mechanisms of action and expression of these substances, as well as their role on ovarian function.Review: The IGF-I is a peptide structurally similar to proinsulin, and is part of IGF-I system. This system comprises two receptors with their respective ligands and six high-affinity IGF binding proteins. Its action is mediated by binding to its specific receptor tyrosine kinase (IGFR-I), that initiates the activation of PI3K and /or MAPK pathway. In ovary, this growth factor was observed in different compartment of follicle (granulosa cells, theca cells and oocyte). IGF-I is the main cell survival factor in the ovary, it protects cell from apoptosis promoted by several agents. Activation of the IGF-I receptor is a particularly important survival-promoting signal during follicular development. The involvement of IGF-I in the early stage...(AU)

Role of Insulin-like growth factor-I (IGF-I) and Kit Ligand (KL) in ovarian function / Papel do fator de crescimento semelhante à Insulina-I (IGF-I) e Kit Ligand (KL) na função ovariana

Background: The ovarian function is coordinated by many growth factors and hormones responsible for ensuring the success of follicular and oocyte development. To obtain competent oocytes is necessary to have a perfect interaction between follicular somatic cells and the oocyte, which is potentially regulated by paracrine factors produced in the ovary. Among these factors, we highlight the insulin-like growth factor-I (IGF-I) and Kit ligand (KL). This review summarizes the main aspects of molecular structure of IGF-I and KL and their receptors, the mechanisms of action and expression of these substances, as well as their role on ovarian function.Review: The IGF-I is a peptide structurally similar to proinsulin, and is part of IGF-I system. This system comprises two receptors with their respective ligands and six high-affinity IGF binding proteins. Its action is mediated by binding to its specific receptor tyrosine kinase (IGFR-I), that initiates the activation of PI3K and /or MAPK pathway. In ovary, this growth factor was observed in different compartment of follicle (granulosa cells, theca cells and oocyte). IGF-I is the main cell survival factor in the ovary, it protects cell from apoptosis promoted by several agents. Activation of the IGF-I receptor is a particularly important survival-promoting signal during follicular development. The involvement of IGF-I in the early stage...

Associação das técnicas de criopreservação e cultivo in vitro de folículos pré-antrais para a obtenção de embriões caprinos / Cryopreservation and in vitro culture of ovarian preantral follicles to obtaining goat embryos

A criopreservação tem sido de extrema importância para a preservação de material genético de machos e fêmeas para a utilização posterior em programas de reprodução assistida. Por essa razão, o emprego da criopreservação de oócitos inclusos em folículos ovarianos pré-antrais tem se mostrado como uma ferramenta complementar para as biotecnologias da reprodução que visam maximizar o potencial reprodutivo de animais de grande valor genético mesmo após a morte ou descarte programado. A aplicação da criopreservação de folículos pré-antrais, isolados ou inclusos no tecido ovariano, permitirá a implantação de bancos de germoplasma animal/humano, com o intuito de preservar o patrimônio genético e, consequentemente, a preservação e manutenção da fertilidade de fêmeas. Vários estudos em diferentes espécies, notadamente em humanos, têm demonstrado a retomada da função reprodutiva relatando inclusive o nascimento de crias saudáveis após transplante de tecido ovariano previamente criopreservado. No entanto, em pequenos ruminantes, especialmente em caprinos, os avanços ainda são pouco significativos. Portanto, conclui-se que mais estudos são requeridos com o objetivo de definir um protocolo (congelação lenta ou vitrificação) que garanta a viabilidade e função ovariana e folicular, normais após a descongelação/aquecimento.(AU)

Cryopreservation has been extremely important for the preservation of male and female genetic material for later use in assisted reproduction procedures. Thus, the use of cryopreservation of oocytes enclosed in preantral follicles has been shown as a complementary tool for the reproduction biotechnologies aimed at maximizing the reproductive potential of animals of great genetic value even after death, unexpected or not, as well as after planed elimination. The application of isolated or in situ preantral follicles cryopreservation, will allow salvage animal genetic resources in gene/banks animal / or even genetic human, and consequently to preserve and maintaining the female fertility. Several studies in different species, especially humans, have demonstrated the resumption of reproductive function including reporting the birth of healthy offspring after transplantation of cryopreserved ovarian tissue previously. However, in small ruminants, especially in goats, improvements are still not very significant. Therefore, it is concluded that further studies are required in order to define a protocol (slow freezing or vitrification) that ensures the viability and normal function of ovary and preantral follicles after thawing/warming.(AU)

Associação das técnicas de criopreservação e cultivo in vitro de folículos pré-antrais para a obtenção de embriões caprinos / Cryopreservation and in vitro culture of ovarian preantral follicles to obtaining goat embryos

A criopreservação tem sido de extrema importância para a preservação de material genético de machos e fêmeas para a utilização posterior em programas de reprodução assistida. Por essa razão, o emprego da criopreservação de oócitos inclusos em folículos ovarianos pré-antrais tem se mostrado como uma ferramenta complementar para as biotecnologias da reprodução que visam maximizar o potencial reprodutivo de animais de grande valor genético mesmo após a morte ou descarte programado. A aplicação da criopreservação de folículos pré-antrais, isolados ou inclusos no tecido ovariano, permitirá a implantação de bancos de germoplasma animal/humano, com o intuito de preservar o patrimônio genético e, consequentemente, a preservação e manutenção da fertilidade de fêmeas. Vários estudos em diferentes espécies, notadamente em humanos, têm demonstrado a retomada da função reprodutiva relatando inclusive o nascimento de crias saudáveis após transplante de tecido ovariano previamente criopreservado. No entanto, em pequenos ruminantes, especialmente em caprinos, os avanços ainda são pouco significativos. Portanto, conclui-se que mais estudos são requeridos com o objetivo de definir um protocolo (congelação lenta ou vitrificação) que garanta a viabilidade e função ovariana e folicular, normais após a descongelação/aquecimento.

Cryopreservation has been extremely important for the preservation of male and female genetic material for later use in assisted reproduction procedures. Thus, the use of cryopreservation of oocytes enclosed in preantral follicles has been shown as a complementary tool for the reproduction biotechnologies aimed at maximizing the reproductive potential of animals of great genetic value even after death, unexpected or not, as well as after planed elimination. The application of isolated or in situ preantral follicles cryopreservation, will allow salvage animal genetic resources in gene/banks animal / or even genetic human, and consequently to preserve and maintaining the female fertility. Several studies in different species, especially humans, have demonstrated the resumption of reproductive function including reporting the birth of healthy offspring after transplantation of cryopreserved ovarian tissue previously. However, in small ruminants, especially in goats, improvements are still not very significant. Therefore, it is concluded that further studies are required in order to define a protocol (slow freezing or vitrification) that ensures the viability and normal function of ovary and preantral follicles after thawing/warming.

Implicações da insulina na função ovariana e desenvolvimento embrionário / Implications of insulin in ovarian function and embryonic development

A insulina é um hormônio essencialmente envolvido na regulação da concentração da glicose na circulação, além de atuar no crescimento celular e no desenvolvimento de uma ampla variedade de tipos celulares, incluindo o ovário. Em geral, os efeitos desse hormônio nas células ovarianas de mamíferos são positivos, estimulando nas células da granulosa a sua proliferação, a atividade da aromatase e a produção de esteróides, além de ser um fator regulador da maturação oocitária. Assim, este artigo tem como objetivo relatar os principais efeitos biológicos da insulina na reprodução de fêmeas. Ao longo deste trabalho, foram mostrados aspectos relacionados à estrutura e ação da insulina e seu receptor, presença da insulina e seu receptor no ovário e o papel deste hormônio na reprodução de fêmeas. A insulina é um hormônio de caráter anabólico, produzido pelas células ẞ pancreáticas. A sua ação na célula inicia-se pela sua ligação ao receptor de membrana plasmática. No ambiente ovariano, a insulina é um importante modulador do desenvolvimento folicular, esteroidogênese, maturação oocitária e subseqüente desenvolvimento embrionário. Assim, hormônios metabólicos, como a insulina, regulam o desenvolvimento folicular modulando o recrutamento, o desenvolvimento e a maturação folicular. Apesar dos grandes avanços científicos ocorridos sobre os mecanismos de ação da insulina, ainda verifica-se a necessidade de mais estudos com a finalidade de explicar melhor seus efeitos na foliculogênese em mamíferos, bem como a influência desses efeitos na posterior maturação dos oócitos crescidos in vitro.

Insulin is a hormone essentially involved in the blood glucose level regulation, besides it acts on cell growth and development of a several variety of cell types, including the ovarian cells. In general, the effects of this hormone in ovarian cells of mammals are positive, it stimulates in granulosa cells proliferation, aromatase activity and steroid production, also it is a factor that regulates the oocyte maturation. Therefore, this review described the main biological effects of insulin in female mammalian reproduction, with emphasis on ovarian folliculogenesis, oocyte maturation and embryonic development. This paper shows the structure and action aspects of insulin and its receptor, the presence of insulin and its receptor in the ovary and the role of this hormone in female reproduction. Insulin is an anabolic hormone produced by pancreatic ẞ cells. Its action starts in the cell by binding to the in cell plasma membrane receptor. In the ovarian environment, insulin is an important modulator of follicular development, steroidogenesis, oocyte maturation and subsequent embryonic development. Thus, metabolic hormones such as insulin regulate the follicular development by modulating the follicular recruitment, development and maturation. Despite significant scientific advances that have occurred on the mechanisms of insulin action, there is yet to be better explained its effects on folliculogenesis in mammals, as well as the influence of these effects in the subsequent maturation of oocytes grown in vitro.

Caracterização estrutural do fator de crescimento de fibroblasto-10 (FGF-10) e seu papel na fisiologia folicular ovariana / Structural characterization of the fibroblast growth factor-10 (FGF-10) and its role in ovarian follicular physiology

Background: Interest in folliculogenesis has grown extensively in recent years. Nevertheless, several aspects of follicular activity are still poorly understood. Thus, in vitro culture of ovarian follicles using new substances has been established as a very viable model, enhancing the prospects for a better understanding of follicular activity. Among the family members of the fibroblast growth factor (FGFs), FGF-10 has received recent attention for its ability to regulate the development of ovarian follicles and oocyte maturation. Given the relevance of FGF-10 in the folliculogenesis process, this review aimed to describe the structural features, expression and the main biological effects of FGF-10 on the development of ovarian follicles in mammals. Review: Along this work, it was shown aspects related to structural characterization of FGF-10 and its receptors, as well as FGF-10 expression in different cell types, emphasizing its importance to follicular development. FGF-10 is a paracrine member of the family of FGFs, and is characterized by promoting biological responses via cell surface receptors (FGFRs) of tyrosine kinase-type. Of these receptors, FGFR-1, FGFR-2 and FGFR-3 may undergo alternative transcriptional arrangements, enabling the formation of two isoforms (b and c) that have varying degrees of affinity for the various FGFs. Thus, seven FGFR proteins (FGFRs 1b, 1c, 2b, 2c, 3b, 3c and 4) with different binding specificities are generated from the four FGFR genes. The FGFRs transmit intracellular signals after binding with the ligand through the phosphorylation of tyrosine, which activates various transduction patterns in the cytoplasm. The signal transduction of FGF-10 may occur through three main pathways: protein of rat sarcoma (Ras)/MAPK, PLCg/Ca2+ and phosphatidylinositol-3 kinase (PI3K)/ protein kinase B (Akt), which are involved in the transmission of biological signals, leading to cellular proliferation and differentiation. FGF-10 mRNA expression was detected in the ovarian stroma, oocyte and theca cells of preantral and antral follicles. On the other hand, the expression of mRNA for FGF-10 receptors was found in, granulosa cells, theca cells, cumulus cells and oocytes. Although FGFs are widely distributed in different tissues and cell types, the importance and function of FGFs in the ovary are still poorly documented. FGF-10 has been shown to be an important mediator of mesenchymal and epithelial cell interactions during follicle development, promoting follicular survival, activation and growth. Besides the action on folliculogenesis, FGF-10 was recently identified as a growth factor able to improve oocyte competence. However, in antral follicles, the presence of FGF-10 is associated with increased follicular atresia, which matches its anti-estrogenic action. Discussion: From this review, we can conclude that FGF-10 is an important regulator of female reproduction. This growth factor acts in follicle survival, oocyte maturation, expansion of cumulus cells and proliferation of granulosa/theca cells through direct and/or indirect actions in the control of folliculogenesis. Furthermore, FGF-10 seemed to have different effects throughout the follicular development. However, it is necessary to perform additional studies that may provide a better understanding about the importance of FGF-10 during folicullogenesis.(AU)

Caracterização estrutural do fator de crescimento de fibroblasto-10 (FGF-10) e seu papel na fisiologia folicular ovariana / Structural characterization of the fibroblast growth factor-10 (FGF-10) and its role in ovarian follicular physiology

Background: Interest in folliculogenesis has grown extensively in recent years. Nevertheless, several aspects of follicular activity are still poorly understood. Thus, in vitro culture of ovarian follicles using new substances has been established as a very viable model, enhancing the prospects for a better understanding of follicular activity. Among the family members of the fibroblast growth factor (FGFs), FGF-10 has received recent attention for its ability to regulate the development of ovarian follicles and oocyte maturation. Given the relevance of FGF-10 in the folliculogenesis process, this review aimed to describe the structural features, expression and the main biological effects of FGF-10 on the development of ovarian follicles in mammals. Review: Along this work, it was shown aspects related to structural characterization of FGF-10 and its receptors, as well as FGF-10 expression in different cell types, emphasizing its importance to follicular development. FGF-10 is a paracrine member of the family of FGFs, and is characterized by promoting biological responses via cell surface receptors (FGFRs) of tyrosine kinase-type. Of these receptors, FGFR-1, FGFR-2 and FGFR-3 may undergo alternative transcriptional arrangements, enabling the formation of two isoforms (b and c) that have varying degrees of affinity for the various FGFs. Thus, seven FGFR proteins (FGFRs 1b, 1c, 2b, 2c, 3b, 3c and 4) with different binding specificities are generated from the four FGFR genes. The FGFRs transmit intracellular signals after binding with the ligand through the phosphorylation of tyrosine, which activates various transduction patterns in the cytoplasm. The signal transduction of FGF-10 may occur through three main pathways: protein of rat sarcoma (Ras)/MAPK, PLCg/Ca2+ and phosphatidylinositol-3 kinase (PI3K)/ protein kinase B (Akt), which are involved in the transmission of biological signals, leading to cellular proliferation and differentiation. FGF-10 mRNA expression was detected in the ovarian stroma, oocyte and theca cells of preantral and antral follicles. On the other hand, the expression of mRNA for FGF-10 receptors was found in, granulosa cells, theca cells, cumulus cells and oocytes. Although FGFs are widely distributed in different tissues and cell types, the importance and function of FGFs in the ovary are still poorly documented. FGF-10 has been shown to be an important mediator of mesenchymal and epithelial cell interactions during follicle development, promoting follicular survival, activation and growth. Besides the action on folliculogenesis, FGF-10 was recently identified as a growth factor able to improve oocyte competence. However, in antral follicles, the presence of FGF-10 is associated with increased follicular atresia, which matches its anti-estrogenic action. Discussion: From this review, we can conclude that FGF-10 is an important regulator of female reproduction. This growth factor acts in follicle survival, oocyte maturation, expansion of cumulus cells and proliferation of granulosa/theca cells through direct and/or indirect actions in the control of folliculogenesis. Furthermore, FGF-10 seemed to have different effects throughout the follicular development. However, it is necessary to perform additional studies that may provide a better understanding about the importance of FGF-10 during folicullogenesis.

Efeito da temperatura e do tempo de transporte de tecido ovariano sobre a viabilidade de folículos pré-antrais caprinos cultivados IN VITRO

O objetivo do presente estudo foi avaliar o efeito da conservação de fragmentos ovarianos em diferentes temperaturas e tempos de conservação sobre a viabilidade e crescimento in vitro de folículos pré-antrais caprinos após cultivo in vitro. Os ovários caprinos (n=10) foram obtidos de animais de abatedouro. Cada par ovariano foi dividido em 19 fragmentos. Um fragmento foi imediatamente fixado para histologia clássica e microscopia eletrônica de transmissão (controle fresco dia 0). Os fragmentos restantes foram distribuídos em Meio Essencial Mínimo (MEM) e mantidos a 4, 20 ou 35°C por 2 ou 4 h. Após cada tempo de conservação, fragmentos (n=30) foram fixados (não cultivados), enquanto fragmentos (n=60) foram cultivados in vitro por 1 ou 7 dias a 39?C e 5% de CO2 em MEM suplementado. Após cada período de conservação e/ou cultivo, os fragmentos foram submetidos à histologia clássica e microscopia eletrônica de transmissão a fim de avaliar a morfologia folicular. Após 7 dias de cultivo, somente os fragmentos ovarianos armazenados a 4°C por 4 h mantiveram o percentual de folículos morfologicamente normais equivalentes ao controle fresco (P>0,05). Observou-se que em todos os tratamentos ocorreu uma redução (P>0,05) no número de folículos primordiais e um concomitante aumento nos folículos em desenvolvimento, indicando ativação. Além disso, houve um aumento no diâmetro oocitário e folicular após o cultivo de córtex ovariano submetido à conservação na temperatura de 4 °C por 2 e 4 h. A microscopia eletrônica de transmissão confirmou a histologia clássica, mostrando que a conservação na temperatura de 4 °C por 4 h, 20 e 35 °C por 2 h ajudou a manter a integridade morfológica dos folículos pré-antrais caprinos após 7 dias de cultivo. Em conclusão, os fragmentos ovarainos caprinos armazenados a 4°C por até 4 h melhoram a viabilidade folicular durante transporte e aumenta o crescimento folicular durante cultivo in vitro