Hyperinsulinemic hypoglycemia secondary to multiple beta cell adenomas in a boxer bitch

Background: The most frequent pancreatic tumours are derived from insulin-secreting β cells, commonly called insulinomas; these are characterised by high insulin secretion causing hypoglycemia and clinical signs such as seizures,tremors, weakness, and polyphagia, among others. In dogs, this tumour represents <0.5% of neoplasias; the majority aresolitary carcinoma masses and rarely adenomas. Insulin-secreting tumours are usually diagnosed in middle-aged or olderdogs. There is no apparent sex predilection for the disease and it has been mainly reported in medium to large breeds.Independently of whether they are adenomas or carcinomas, dogs have the same disease-free time and survival time andthe prognosis is poor.Case: An 8-year-old female Boxer was brought to the University Veterinary Hospital with a history of weakness, tremors,and generalised convulsions. Physical examination, CBC and urinalysis revealed no abnormalities. In the blood chemistryprofile, hypoglycemia was detected along with hyperinsulinemia. An abdominal ultrasound revealed the presence of twoabnormal masses located in the pancreas. The insulin:glucose ratio was 59.8. Exploratory celiotomy was performed andtwo masses were located in the mesentery, adjacent to the left pancreatic lobe, and a third was in the pancreatic tissue ofthe same lobule. All masses were resected during the same surgery. Cytology of the masses coincided with apparentlymalignant insulinoma, however, the histopathological and immunohistochemically report indicated an insulin-secretingadenoma. The patient improved clinically and remained stable for approximately 545 days, after which seizures relapsedand a new treatment was not approved. The patient died 575 days after surgery.Discussion: In dogs, pancreatic islet cell tumours correspond to endocrinologically active neoplasm that secrete hormonesand are associated with functional disorders (hyperinsulinemia) in relation to hypoglycemia...

Hyperinsulinemic hypoglycemia secondary to multiple beta cell adenomas in a boxer bitch

Background: The most frequent pancreatic tumours are derived from insulin-secreting β cells, commonly called insulinomas; these are characterised by high insulin secretion causing hypoglycemia and clinical signs such as seizures,tremors, weakness, and polyphagia, among others. In dogs, this tumour represents <0.5% of neoplasias; the majority aresolitary carcinoma masses and rarely adenomas. Insulin-secreting tumours are usually diagnosed in middle-aged or olderdogs. There is no apparent sex predilection for the disease and it has been mainly reported in medium to large breeds.Independently of whether they are adenomas or carcinomas, dogs have the same disease-free time and survival time andthe prognosis is poor.Case: An 8-year-old female Boxer was brought to the University Veterinary Hospital with a history of weakness, tremors,and generalised convulsions. Physical examination, CBC and urinalysis revealed no abnormalities. In the blood chemistryprofile, hypoglycemia was detected along with hyperinsulinemia. An abdominal ultrasound revealed the presence of twoabnormal masses located in the pancreas. The insulin:glucose ratio was 59.8. Exploratory celiotomy was performed andtwo masses were located in the mesentery, adjacent to the left pancreatic lobe, and a third was in the pancreatic tissue ofthe same lobule. All masses were resected during the same surgery. Cytology of the masses coincided with apparentlymalignant insulinoma, however, the histopathological and immunohistochemically report indicated an insulin-secretingadenoma. The patient improved clinically and remained stable for approximately 545 days, after which seizures relapsedand a new treatment was not approved. The patient died 575 days after surgery.Discussion: In dogs, pancreatic islet cell tumours correspond to endocrinologically active neoplasm that secrete hormonesand are associated with functional disorders (hyperinsulinemia) in relation to hypoglycemia...(AU)

Effects of bovine enterovirus and type 1 diabetes on liver and kidney pyruvate kinase activity in an animal model

Type 1 diabetes (T1D) is an autoimmune disease characterized by the selective destruction of pancreatic beta cells. In addition to genetic factors, enteroviruses have been considered the main environmental factor involved in this pathology. Therefore, the objective of this study was to evaluate the effects of streptozotocin-induced diabetes and bovine enterovirus (BEV) on liver and kidney pyruvate kinase activity in rats. Fourteen male Wistar rats were divided in three groups: control, diabetes and a third group, which was fed with water experimentally contaminated by BEV. Increased blood glucose levels were found in both diabetes and enterovirus groups, whereas there were no alterations in the lipid profile. A reduced pyruvate kinase activity was observed in the liver and kidney of animals from diabetes and enterovirus groups. Under our experimental conditions, the ingestion of water experimentally contaminated by BEV induced alterations in glycaemia, and also interfered in the pyruvate kinase activity in liver and kidney of the rats, which might be one of the possible mechanisms involved in the T1D development.

Effects of bovine enterovirus and type 1 diabetes on liver and kidney pyruvate kinase activity in an animal model

Type 1 diabetes (T1D) is an autoimmune disease characterized by the selective destruction of pancreatic beta cells. In addition to genetic factors, enteroviruses have been considered the main environmental factor involved in this pathology. Therefore, the objective of this study was to evaluate the effects of streptozotocin-induced diabetes and bovine enterovirus (BEV) on liver and kidney pyruvate kinase activity in rats. Fourteen male Wistar rats were divided in three groups: control, diabetes and a third group, which was fed with water experimentally contaminated by BEV. Increased blood glucose levels were found in both diabetes and enterovirus groups, whereas there were no alterations in the lipid profile. A reduced pyruvate kinase activity was observed in the liver and kidney of animals from diabetes and enterovirus groups. Under our experimental conditions, the ingestion of water experimentally contaminated by BEV induced alterations in glycaemia, and also interfered in the pyruvate kinase activity in liver and kidney of the rats, which might be one of the possible mechanisms involved in the T1D development.(AU)

Resistência à insulina e metabolismo de glicose na gestação, um paralelo entre equinos e humanos / Insulin resistance and glucose metabolism in pregnancy, a parallel between equines and humans

O metabolismo de glicose se adapta à gestação e lactação em várias espécies, incluindo os equinos. Essa adaptação envolve tanto o desenvolvimento progressivo fisiológico de resistência à insulina no tecido alvo, quanto o aumento na secreção de insulina pelas células β pancreáticas. A resistência a insulina, hiperinsulinemia e obesidade ou aumento da adiposidade regional são os três componentes principais da Síndrome Metabólica Equina. Ela pode levar à laminite, subfertilidade em éguas e garanhões, maior risco de distocias e aumento da chance de doenças ortopédicas e deformidades angulares em potros. Em humanos, as adaptações hematobioquímicas da gestação são conhecidas e os valores de referência em exames laboratoriais são diferentes entre mulheres gestantes e não gestantes. Em equinos ainda não existem estes valores para diagnóstico de resistência à insulina e/ou Diabetes Mellitus Gestacional em éguas prenhes. Desta forma, o objetivo desse trabalho é traçar um paralelo entre o descrito em mulheres gestantes e equinos.(AU)

Glucose metabolism adapts to gestation and lactation in several species, including horses. This adaptation involves the progressive physiological development of insulin resistance in target tissues and the increase in insulin secretion by pancreatic β cells. Insulin resistance and hyperinsulinemia together with obesity or increased regional adiposity are the three main components of Equine Metabolic Syndrome (EMS). EMS causes alterations in several systems of the body, leading to laminitis, fertility problems in mares and stallions, increased risk of dystocia and chance of orthopedic diseases and angular deformities in foals from affected mares. In humans, it is well known that due to the hematobiochemical adaptations of pregnancy, the reference values in laboratory tests are different between pregnant and non-pregnant women. Currently in equine, there are no reference values to diagnose insulin resistance and / or Gestational Diabetes Mellitus (GDM). Therefore, the objective of this review is to establish a parallel between what has been described in pregnant women and mares.(AU)

Resistência à insulina e metabolismo de glicose na gestação, um paralelo entre equinos e humanos / Insulin resistance and glucose metabolism in pregnancy, a parallel between equines and humans

O metabolismo de glicose se adapta à gestação e lactação em várias espécies, incluindo os equinos. Essa adaptação envolve tanto o desenvolvimento progressivo fisiológico de resistência à insulina no tecido alvo, quanto o aumento na secreção de insulina pelas células β pancreáticas. A resistência a insulina, hiperinsulinemia e obesidade ou aumento da adiposidade regional são os três componentes principais da Síndrome Metabólica Equina. Ela pode levar à laminite, subfertilidade em éguas e garanhões, maior risco de distocias e aumento da chance de doenças ortopédicas e deformidades angulares em potros. Em humanos, as adaptações hematobioquímicas da gestação são conhecidas e os valores de referência em exames laboratoriais são diferentes entre mulheres gestantes e não gestantes. Em equinos ainda não existem estes valores para diagnóstico de resistência à insulina e/ou Diabetes Mellitus Gestacional em éguas prenhes. Desta forma, o objetivo desse trabalho é traçar um paralelo entre o descrito em mulheres gestantes e equinos.

Glucose metabolism adapts to gestation and lactation in several species, including horses. This adaptation involves the progressive physiological development of insulin resistance in target tissues and the increase in insulin secretion by pancreatic β cells. Insulin resistance and hyperinsulinemia together with obesity or increased regional adiposity are the three main components of Equine Metabolic Syndrome (EMS). EMS causes alterations in several systems of the body, leading to laminitis, fertility problems in mares and stallions, increased risk of dystocia and chance of orthopedic diseases and angular deformities in foals from affected mares. In humans, it is well known that due to the hematobiochemical adaptations of pregnancy, the reference values in laboratory tests are different between pregnant and non-pregnant women. Currently in equine, there are no reference values to diagnose insulin resistance and / or Gestational Diabetes Mellitus (GDM). Therefore, the objective of this review is to establish a parallel between what has been described in pregnant women and mares.

Insulinoma canino: relato de caso / Canine insulinoma: case reports

O insulinoma é um tumor das células ß do pâncreas, que têm a função de produzir e secretar insulina e, geralmente são malignos em cães. O presente trabalho descreve o diagnóstico e o manejo terapêutico de três casos de insulinoma. Os sinais clínicos dos animais relatados variaram de acordo com a severidade e a duração da hipoglicemia. O diagnóstico presuntivo se deu através dos sinais clínicos e da dosagem de insulina sérica no momento de mais intensa hipoglicemia e, o diagnóstico definitivo foi obtido por meio de exame histopatológico nos três casos relatados. O tratamento realizado variou de acordo com a intensidade dos sinais clínicos.(AU)

Insulinoma is a tumor of the ß cells of the pancreas, which have the function to produce and secrete insulin and are usually malignant in dogs. This paper describes the diagnosis and therapeutic management of three cases of insulinoma. The clinical signs reported animals varied according to the severity and duration of hypoglycemia. The presumptive diagnosis was based on clinical signs and serum insulin dosage at the time of hypoglycemia and more intense, the definitive diagnosis was made by histopathological examination in three of the reported cases. The treatment was varied according to the severity of clinical signs.(AU)

Insulinoma canino: relato de caso / Canine insulinoma: case reports

O insulinoma é um tumor das células ß do pâncreas, que têm a função de produzir e secretar insulina e, geralmente são malignos em cães. O presente trabalho descreve o diagnóstico e o manejo terapêutico de três casos de insulinoma. Os sinais clínicos dos animais relatados variaram de acordo com a severidade e a duração da hipoglicemia. O diagnóstico presuntivo se deu através dos sinais clínicos e da dosagem de insulina sérica no momento de mais intensa hipoglicemia e, o diagnóstico definitivo foi obtido por meio de exame histopatológico nos três casos relatados. O tratamento realizado variou de acordo com a intensidade dos sinais clínicos.(AU)

Insulinoma is a tumor of the ß cells of the pancreas, which have the function to produce and secrete insulin and are usually malignant in dogs. This paper describes the diagnosis and therapeutic management of three cases of insulinoma. The clinical signs reported animals varied according to the severity and duration of hypoglycemia. The presumptive diagnosis was based on clinical signs and serum insulin dosage at the time of hypoglycemia and more intense, the definitive diagnosis was made by histopathological examination in three of the reported cases. The treatment was varied according to the severity of clinical signs.(AU)

Malignant metastatic insulinoma in a dog

Background: Insulinomas are tumors of the pancreatic islet beta cells that secreting insulin. They are malignant neoplasms and rarely seen in dogs. Because insulinomas secrete excessive insulin and hypoglycemia occur. The most common clinical symptoms are seizures, extreme weakness, and other neurological abnormalities. The tumors typically release insulin episodically, with clinical signs being seen intermittently as a result. These are most often associated with prolonged starvation or prolonged periods of exertion. Insulinoma occurs most often in middle-aged and older dogs, averaging nine years in age. They affect both sexes and are more likely in larger breeds. The most commonly afflicted breeds are German Shepherds, Irish Setters, Boxers, Golden Retrievers and Terriers. Case: In this study, a case of malignant insulinoma with multiorgan metastasis in a 7-year-old hunting dog that brought to the clinic with complaints of constipation and inappetence were evaluated by clinical, cytological, histopathological and immunohistochemical findings. Owner stated that the animal suffers from constipation for 4 days, but no vomitus or nervous symptoms were present. Clinical efforts not solved the constipation. For to the definitive diagnosis the dog decided to underwent laparotomy. After a midline abdominal approach multiple whitish, hard and irregular metastatic tumoral masses were[...]

Malignant metastatic insulinoma in a dog

Background: Insulinomas are tumors of the pancreatic islet beta cells that secreting insulin. They are malignant neoplasms and rarely seen in dogs. Because insulinomas secrete excessive insulin and hypoglycemia occur. The most common clinical symptoms are seizures, extreme weakness, and other neurological abnormalities. The tumors typically release insulin episodically, with clinical signs being seen intermittently as a result. These are most often associated with prolonged starvation or prolonged periods of exertion. Insulinoma occurs most often in middle-aged and older dogs, averaging nine years in age. They affect both sexes and are more likely in larger breeds. The most commonly afflicted breeds are German Shepherds, Irish Setters, Boxers, Golden Retrievers and Terriers. Case: In this study, a case of malignant insulinoma with multiorgan metastasis in a 7-year-old hunting dog that brought to the clinic with complaints of constipation and inappetence were evaluated by clinical, cytological, histopathological and immunohistochemical findings. Owner stated that the animal suffers from constipation for 4 days, but no vomitus or nervous symptoms were present. Clinical efforts not solved the constipation. For to the definitive diagnosis the dog decided to underwent laparotomy. After a midline abdominal approach multiple whitish, hard and irregular metastatic tumoral masses were[...](AU)

OTIMIZAÇÃO DE MEIO DE DIFERENCIAÇÃO PARA ORGANOIDES PANCREÁTICOS CANINOS

A diabetes mellitus é uma doença metabólica crônica de causa multifatorial onde a produção da insulina e/ou sua ação podem estar prejudicadas. A ocorrência natural de condição clínica em cães semelhante a Diabetes mellitus tipo 1 (DMT1) humana impulsionou o uso desta espécie em estudos de novas possibilidades terapêuticas. A DMT1 tem como base a destruição das células que produzem insulina e, por essa razão, a terapia celular com organoides diferenciados em células semelhantes à poderiam representar, finalmente, a cura da doença. Organoides são estruturas tridimensionais derivadas de células-tronco embrionárias ou tecidoespecíficas com habilidade de auto-organização, diferenciação celular e morfogênese semelhante ao órgão correspondente. Fragmentos de tecido pancreático fresco de três cães submetidos à eutanásia na Faculdade de Veterinária de Utrecht, Holanda, foram isolados, cultivados em meio de expansão e transferidos para meios de diferenciação em dois experimentos com objetivo de otimizar o meio para produção de células semelhantes à produtoras de insulina. Os organoides foram caracterizados pela expressão gênica através de reação em cadeia mediada pela polimerase quantitativa (qPCR). Os resultados demonstraram a presença de células-tronco adultas com perfil gênico de células ductais em meio de expansão e potencial de diferenciação in vitro. Observou-se o aumento gradual da expressão dos marcadores Pdx1 e Nkx6.1 (precursores endócrinos) proporcional à duração do protocolo. Entretanto, marcadores de células endócrinas maduras não foram detectados. A adição de novos componentes, a duração dos estágios de diferenciação e o uso de sistema de suspensão de cultura de células são alternativas que podem ser testadas em futuras abordagens visando a obtenção de células produtoras de insulina que possam ser usadas na terapia celular.

Diabetes mellitus is a chronic metabolic disease of multifactorial cause where insulin production and/or its action may be impaired. The natural occurence of a clinical condition in dogs similar to human Type 1 diabetes mellitus (T1DM) has boosted its use as an experimental model in studies of new therapeutic possibilities. The destruction of beta cells that produce insulin is the basis of T1DM and, for this reason, cell therapy with organoids differentiated into stem cell beta-like cells could ultimately represent the cure of the disease. Organoids are threedimensional structures derived from embryonic stem cells or tissue-specific stem cell with ability to self-organization, cell differentiation and morphogenesis similar to the corresponding organ. Fragments of fresh pancreatic tissue from three dogs submitted to euthanasia at Veterinary School of Utrecht, The Netherlands, were isolated, cultivated in expansion medium and transferred to differentiation media in two experiments aiming the optimization of the medium for production of functional beta-like cells. Organoids were characterized by gene expression through quantitative chain reaction mediated by polymerase (qPCR). The results demonstrated the presence of adult stem cell with ductal cell profile in expansion medium and in vitro differentiation potential. A gradual increase in Pdx1 and Nkx6.1 (endocrine precursors) markers expression was noted, proportional to the duration of the protocol. However, endocrine mature cell markers were not detected. The addition of new components, the duration of differentiation stages and the use of a suspension cellular culture system are alternatives that can be tested in future approaches in order to obtain insulin-producing cells that can be used in cell therapy.

DIFERENCIAÇÃO DE CÉLULAS TRONCO DO TECIDO ADIPOSO EM CÉLULAS PRODUTORAS DE INSULINA: comparação de diferentes composições do meio de cultivo

A diabetes mellitus (DM) tipo 1 é uma doença comum em homens e cães, com complicações sérias e sem cura. Os tratamentos disponíveis apresentam limitações e não mimetizam o controle fisiológico que a secreção de insulina, pelas células beta pancreáticas, exercem na glicemia. Neste contexto, células tronco mesenquimais (CTM) de diferentes espécies têm sido utilizadas para a diferenciação em células beta funcionais. Os cães são utilizados como modelo de estudo da DM tipo 1 humana, devido às suas similaridades quanto à apresentação e ao curso da doença. No entanto, nesta espécie, pouco se sabe sobre a diferenciação in vitro das CTM em células produtoras de insulina (CPI). O objetivo deste estudo foi diferenciar células tronco mesenquimais do tecido adiposo (CTM-TA) de cães em CPI, por diferentes composições do meio de cultura, a fim de determinar a que promove melhor diferenciação. As células isoladas da gordura peri-uterina, após a terceira passagem, apresentaram características de CTM, como elevada expressão de CD90 e CD29 e baixa expressão de CD45 e CD34, além da capacidade para se diferenciar em adipócitos, condroblastos e osteoblastos. As CTM-TA foram distribuídas em seis grupos, de acordo com os meios de cultura: 1) DMEM/F12 alta glicose sem soro fetal bovino (SFB), ß-mercaptoetanol e nicotinamida; 2) DMEM/F12 alta glicose sem SFB, ß- mercaptoetanol, nicotinamida e exendin-4; 3) DMEM/F12 alta glicose sem SFB, ß-mercaptoetanol, nicotinamida, exendin-4, suplemento B27, aminoácidos não essenciais e L-glutamina; 4) cultivo em duas etapas, sendo a primeira (8 dias), com DMEM/F12 alta glicose sem SFB, ß-mercaptoetanol, nicotinamida e a segunda, (9-16dias), com o mesmo meio, acrescido de exendin-4, suplemento B27, aminoácidos não essenciais, L-glutamina e FGFb; 5) DMEM/F12 alta glicose sem SFB e 6) DMEM/F12 baixa glicose com 10% de SFB (controle negativo). Durante a diferenciação, as células foram observadas e fotografadas aos 3, 6, 10, 13 e 16 dias. Aos 16 dias, as culturas de células foram coradas por hematoxilina-eosina e por dithizone, marcador da insulina. Foi também avaliada, por RT-PCR, a expressão dos transcritos gênicos, expressos em células beta pancreáticas, como PDX-1, BETA 2, MafA e Insulin. Durante o cultivo, as CTM-TA dos grupos 1 ao 5 tornaram-se gradualmente mais arredondas e reunidas em clusters, semelhantes às ilhotas pancreáticas. Tais mudanças ocorreram de forma diferenciada entre os grupos, sendo que no grupo 3, os clusters de células eram aparentemente mais numerosos, e formavam agregados maiores. Mas, pela coloração por dithizone, os grupos 3 e 4 foram semelhantes com relação ao tamanho da área média corada para insulina. No entanto, somente o grupo 4 apresentou número de agregados de insulina e área total de insulina corada, significativamente maior em comparação aos demais grupos. Houve também expressão de PDX-1, BETA2/NEUROD, mafA e Insulin nos grupos estudados. Conclui-se que, por manipulação da composição do meio de cultivo, é possível induzir a diferenciação das CTM-TA caninas em CPI e que no grupo 4, onde o cultivo foi realizado em duas etapas, houve a melhor diferenciação das CTM-TA em CPI.

Type 1 Diabetes mellitus (DM) is a common disease among men and dogs, which has serious complications and no cure. Available treatments have limitations and do not mimic the physiological control that insulin secretion by pancreatic beta cells exerts on glycaemia. In this context, mesenchymal stem cells (MSC) from different species have been used for differentiation into functional beta cells. Historically, dogs have been used as model for men Type 1 DM studies due to the similarities in the presentation and course of this disease between them. However, in this species, little is known about MSC in vitro differentiation into insulin-producing cells (IPCs). The aim of this study was to differentiate adipose mesenchymal stem cells (ADMSC) into IPCs, by using culture mediums with different compositions, so that the most efficient medium composition is determined. Stem cells isolated from the fat tissue close to the bitch uterus, days after the third passage, presented MSC characteristics such as high expression levels of CD90 and CD29, low expression levels of CD45 and CD34, in addition to the ability to differentiate into adipocytes, chondrocytes and osteocytes. ADMSCs were distributed among six groups, according to the culture mediums: 1) High glucose DMEM/F12 without FCS, ßmercaptoethanol, nicotinamide; 2) High glucose DMEM/F12 without FCS, ßmercaptoethanol, nicotinamide and Exendin-4; 3) High glucose DMEM/F12 without FCS, ß-mercaptoethanol, nicotinamide, Exendin-4, B27 supplement, non essential aminoacids, L-glutamine; 4) 2 stage protocol: stage 1 (8 days) with High glucose DMEM/F12 without FCS, ß- mercaptoethanol, nicotinamide and stage 2 (8 days) with High glucose DMEM/F12 without FCS, ß-mercaptoethanol, nicotinamide, Exendin-4, B27 supplement, non essential aminoacids, L-glutamine and FGFb; 5) High glucose DMEM/F12 without FCS; 6) Low glucose DMEM with 10% FCS (negative control). During differentiation, the cells were observed and photographed at day 3, 6, 10, 13 and 16. At day 16, cells were stained by Hematoxylin-Eosin and Dithizone, an insulin marker. It was also evaluated, by RT-PCR, the expression of transcription factors normally expressed in beta cells, such as PDX-1, BETA 2, MafA and Insulin. Over culture, ADMSCs from groups 1 to 5 gradually became rounder and gathered in clusters, which resembled pancreatic islets. These changes happened in a different way in the groups, so that in group 3 cell clusters were apparently more numerous and gathered in bigger aggregates. However, Dithizone staining showed that groups 3 and 4 were similar in terms of medium area stained for insulin. However, only group 4 had the number of insulin aggregates and the total area of stained insulin significantly bigger than the other groups. The expression of PDX-1, BETA 2, MafA e Insulin was also confirmed in all of the studied groups. We conclude that, by manipulating the composition of the culture medium, it is possible to induce dog ADMSCs into IPCs, and that the group 4, in which a two stage protocol was used, there was the best differentiation of dog ADMSCs into IPCs.

Pancreatic islets isolated from 2 adrenergic receptor knockout mice show reduced insulin secretion in response to nutrients / Ilhotas pancreáticas isoladas de camundongos com deleção do receptor adrenérgico 2 apresenta reduzida secreção de insulina em resposta a nutrientes

Activation of 2 adrenergic receptors by catecholamine or catecholamine-mimetic substances may enhance insulin secretion. We herein investigated KCl- and nutrient-stimulated insulin secretion in pancreatic islets isolated from 2 knockout (2KO) mice. 2KO mice showed reduced body weight, fasting hypoglycaemia associate to a similar fasting insulinemia compared to control. 2KO mice also showed reduced glucose tolerance despite the higher sensitivity to insulin. Glucose-induced insulin secretion was impaired in pancreatic islets isolated from 2KO mice. Leucine-induced (20mM) insulin secretion was diminished in pancreatic islets isolated from 2KO mice when compared to control one. The depolarizing effect of KCl on insulin secretion was also impaired in pancreatic islets from 2KO mice. These results suggested a possible role of 2 adrenergic receptors on nutrient-induced insulin secretion.(AU)

A ativação dos receptores 2-adrenérgicos por catecolaminas ou miméticos a catecolaminas podem aumentar a secreção de insulina. Nós investigamos a secreção de insulina estimulada por nutrients e KCl em ilhotas pancreáticas isoladas de camundongos com deleção dos receptores 2-adrenérgicos (2KO). Camudongos 2KO apresentaram reduzido peso corporal, hipoglicemia de jejum associada a semelhante concentração de insulina plasmática de jejum comparada ao grupo controle. Camundongos 2KO apesar de apresentarem aumento da sensibilidade a insulina também apresentaram reduzida tolerância a glicose. A secreção de insulina induzida com glicose foi alterada em ilhotas pancreáticas isoladas de camundongos 2KO. Secreção de insulina induzida por leucina (20mM) foi diminuída em ilhotas pancreáticas isoladas de camundongos 2KO quando comparado ao controle. O efeito despolarizante do KCl sobre a secreção de insulina também foi alterado em ilhotas pancreáticas de camundongos 2KO. Estes resultados sugerem um possível papel dos receptores 2- adrenérgicos na secreção de insulina induzida por nutrientes.(AU)

Do opioid receptors play a role in the pathogenesis of the inflammatory response in acute pancreatitis? / Os receptores opioides desempenham papel na patogênese da resposta inflamatória na pancreatite aguda?

PURPOSE: To investigate the effect of the opioid blocker naltrexone in the inflammatory response in acute pancreatitis (AP). METHODS: Acute pancreatitis was induced in anesthetized male Wistar rats by retrograde injection of 2.5% sodium taurocholate diluted in 0.5ml saline into the main pancreatic duct. Animals were randomized to the following experimental groups: Control Group (n=9): animals received an intraperitoneal injection of saline solution (0.5ml), 15 minutes before the induction of AP. Naltrexone Group (n=9): animals received an intraperitoneal injection of naltrexone 0.5ml (15 mg/kg), 15 minutes before induction of AP. Peritoneal levels of TNF-α and serum levels of IL-6 and amylase were determined The volume of the ascitic fluid was also evaluated. Myeloperoxidase (MPO) activities were analyzed in homogenates of pulmonary tissue. RESULTS: There were no significant differences in the ascitic fluid volume, nor in TNF-a and IL-6 levels in the naltrexone group compared to controls. Treatment with naltrexone did not affect the lung MPO activity compared to control group. CONCLUSIONS: The opioid receptors don't play an important role in the pathogenesis of the inflammatory response in acute pancreatitis. If opioids affect leukocytes inflammatory signaling, there are no major implications in the pathogenesis of acute pancreatitis.(AU)

OBJETIVO: Investigar o efeito do bloqueador opióide naltrexone na resposta inflamatória da pancreatite aguda. METODOS: Pancreatite aguda foi induzida em ratos machos Wistar, através de injeção retrógada de solução de taurocolato de sódio a 2,5% nos ductos pancreáticos. Os animais foram alocados em dois grupos: Grupo controle (n=9) animais receberam 0,5 ml de solução salina intra-peritonial 15 minutos antes da indução da pancreatite aguda e Grupo naltrexone (n=9) animais receberam naltrexone (15mg/kg de peso), em 0,5 ml de volume final por via intraperitoneal, 15 minutos antes da indução da pancreatite aguda. Foram avaliados o volume de ascite, os níveis séricos de amilase e IL-6, assim como TNF-α peritoneal e a atividade da mieloperoxidase (MPO) no tecido pulmonar. RESULTADOS: Não foram encontradas diferenças significantes nos parâmetros analisados entre o grupo que recebeu solução salina e o que recebeu naltrexone . CONCLUSÕES: Os receptores opióides não desempenham papel importante na resposta inflamatória sistêmica associada à pancreatite aguda. Se os opioides alteram a sinalização inflamatória nos leucócitos está ação não se reflete na patogênese da pancreatite aguda.(AU)

Pathological findings in fetuses of goats and cattle poisoned by Sida carpinifolia (Malvaceae) / Achados patológicos em fetos de caprinos e bovinos intoxicados por Sida carpinifolia (Malvaceae)

In Brazil, the consumption of Sida carpinifolia by livestock has been associated with neurological diseases linked to lysosomal storage disorders. This paper describes the pathological findings in two caprine fetuses from dams that were experimentally poisoned with S. carpinifolia. The goats were orally dosed with 10 and 13g/kg of a paste of green chopped S. carpinifolia for 30 days and were observed for an additional 15 days period after the last dosage with the plant; thereafter they were euthanized and necropsied. The dams showed only slight clinical signs. The study also includes the findings in one bovine fetus from a naturally S. carpinifolia poisoned cow which showed mild incoordination, generalized tremors, staggering, and frequent falls. The cow was euthanized and necropsied. While there were no significant histopathological changes in the goats, in the cow vacuolation of Purkinje neurons of the cerebellum, pancreatic acinar cells, and thyroid follicular cells were observed. The main microscopic changes observed in the caprine and bovine fetuses were vacuolation in the epithelium of renal tubules, thyroid follicular cells, and Purkinje neurons of the cerebellum. Transmission electron microscopy of sections from CNS of the cow and its fetus revealed vacuoles containing fine granular material surrounded by membrane. Lectin-histochemistry of CNS sections from goat fetuses marked lightly to sWGA lectins, WGA, and Con-A.(AU)

No Brasil, o consumo de Sida carpinifolia por animais de produção tem sido associada a doenças neurológicas relacionadas com doença de depósito lisossômico. Este trabalho descreve os achados patológicos observados em dois fetos caprinos de mães que foram experimentalmente intoxicadas por S. carpinifolia. As cabras foram intoxicadas experimentalmente com S. carpinifolia nas doses de 10 e 13g/kg durante 30 dias e foram acompanhadas durante 15 dias após o consumo da planta. Após este período foram eutanasiadas e necropsiadas. O estudo também inclui os achados patológicos encontrados em um feto de uma fêmea bovina intoxicada naturalmente pela planta, que mostrou leve incoordenação, tremores generalizados, andar desequilibrado e quedas frequentes. A vaca foi eutanasiada e necropsiada. Embora não houvesse alterações histológicas significativas nas cabras, vacuolização dos neurônios de Purkinje do cerebelo, das células acinares do pâncreas e nas células foliculares da tireoide foram observadas na vaca. As principais alterações histológicas observadas nos fetos caprinos e no feto bovino foram vacuolização no epitélio dos túbulos renais, nas células foliculares da tireoide e nos neurônios de Purkinje do cerebelo. Na microscopia eletrônica de transmissão do sistema nervoso central da vaca e de seu feto revelaram-se vacúolos contendo material finamente granulado e delimitado por membrana. Na técnica de lectina-histoquímica dos fetos caprinos houve marcação leve no SNC para as lectinas sWGA, WGA e para Con-A.(AU)

Obtenção e caracterização de células derivadas do pâncreas fetal canino

A Diabetes mellitus em cães é cada vez mais frequente, decorrente de fatores genéticos e/ou ambientais, como um distúrbio endócrino que, de forma semelhante à que ocorre em humanos, falha no controle adequado de glicose no sangue, desencadeia a hiperglicemia, glicosúria e perda de peso. A terapia celular utilizando as células beta-pancreáticas tem sido alvo de estudos, devido à grande demanda de novos casos de Diabetes mellitus e à falta de órgãos para transplantes em humanos e animais. Acredita-se que a ciência possa responder e inovar em tratamentos, encontrando a possível cura para esta doença complexa. Portanto, o objetivo deste estudo foi obter e caracterizar células derivadas do pâncreas fetal canino de animais com idades compreendidas entre 50 e 60 dias de gestação. As células pancreáticas de fetos caninos apresentam morfologia fibroblastóide e crescimento em monocamada em cultivo, apresentam células pluripotentes e proliferativas, não são tumorigênicas e apresentam expressão de PDX1, um fator de transcrição que tem papel importante na ativação do gene promotor da insulina. O pâncreas possui inervação simpática, observado por fibras nervosas TH+. Histologicamente, o pâncreas fetal canino apresenta ácinos num estágio de organização avançado, com parênquima semelhante ao encontrado no cão adulto. As ilhotas pancreáticas são distribuídas no tecido de maneira irregular, organizando-se em pequenos aglomerados de células por entre os ácinos, especialmente próximas aos vasos sanguíneos. A coloração com Ditizona permitiu inferir a presença de insulina no tecido pancreático, o que foi comprovado mediante técnica de imunofluorescência, além da presença de células que expressam o hormônio somatostatina. Os resultados desta investigação indicam que o pâncreas fetal canino demonstra características favoráveis para ser uma fonte viável de células para estudos aplicados à terapia celular em cães. Outras investigações referentes à comprovação da produção de insulina in vitro por essas células se fazem necessárias.

Diabetes mellitus in dogs is increasingly common, due to genetic and/or environmental factors such as an endocrine disorder, similarly to what occurs in humans, failure to adequately control blood glucose triggers hyperglycemia, glycosuria and weight loss. Cell therapy using the pancreatic beta cells has been the subject of studies, due to the great demand of new cases of diabetes mellitus and the lack of organs for transplants in humans and animals. It is believed that science can respond and innovate treatments, finding a possible cure for this disease complex. Therefore, the objective of this study was to obtain and characterize derived cells from canine fetal pancreas, of animals aged between 50 and 60 days of gestation. The pancreatic cells of canine fetuses exhibit fibroblastoid morphology and growth in monolayer culture, exhibit pluripotent and proliferative cells, are not tumorigenic and have PDX1 expression, a transcription factor that plays an important role in the activation of the insulin gene promoter. The pancreas has sympathetic innervation observed by TH+ nerve fibers. Histologically, the fetal pancreatic acini canine presents an advanced stage organization with similar parenchyma that found in adult dog. The pancreatic islets are distributed in the fabric unevenly, organizing themselves into small clusters of cells through the acini, especially close to the blood vessels. Staining with Dithizone allowed inferring the presence of insulin in the tissue, which was confirmed by immunofluorescence, in addition to cells that express somatostatin. The results of this investigation indicate that the canine fetal pancreas shows favorable characteristics to be a feasible source of cells for cell therapy applied to studies in dogs. Further investigation regarding the evidence of in vitro production of insulin by these cells are required.

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.

Hematological and biochemical profiles of rats submitted to experimental poisoning with Tityus serrulatus venom / Perfis hematológicos de ratos submetidos ao envenenamento escorpiônico experimental por Tityus serrulatus

The hematological and biochemical profiles of newly weaned rats submitted to experimental poisoning with T. serrulatus venom were evaluated. Fifteen recently weaned male Wistar rats (mean weight 130g) were distributed into three equal groups (n = 5). Animals in the control group (group A) received a subcutaneous injection of 400μL of ultra-pure water, while those in the experimental groups received, by identical route, 400μL of a solution containing 100μg (group B) or 450μg (group C) of scorpion venom dissolved in ultra-pure water. Red blood cells indexes, and differential leukocyte and total platelet counts were determined, together with levels of serum glucose, urea, creatinine, lactic dehydrogenase, aspartate aminotransferase, amylase, insulin, and cortisol. No significant differences between the control and experimental groups regarding red blood cells indexes were found. In contrast, significant increases (P<0.05) in neutrophils, lymphocytes, and monocytes were observed in animals from groups B and C compared with the control group, while the number of platelets decreased. Serum glucose concentration remained unchanged in all groups, but important alterations were observed in the values of urea and creatinine. The results show that scorpion venom was detrimental to renal function as demonstrated by the altered urea and creatinine levels. Pancreatic function was also impaired, as revealed by the increase in amylase activity and the reduction in insulin levels.(AU)

Avaliaram-se os perfis hematológico e bioquímico de ratos recém-desmamados submetidos ao envenenamento experimental com veneno de Tityus serrulatus. Quinze ratos Wistar machos, média de peso de 130g, foram distribuídos aleatoriamente em três grupos (n = 5). Os animais do grupo-controle A foram inoculados com 400μL de água ultrapura, os do grupo experimental B receberam 400μL de uma solução contendo 100μg de veneno e os do grupo experimental C receberam 400μL de uma solução contendo 450μg de veneno. Foram determinados os índices da série vermelha, a contagem total e diferencial dos leucócitos e a contagem total de plaquetas, bem como os níveis da desidrogenase lática, aspartato aminotransferase, amilase, glicose, ureia, creatinina, cortisol e insulina. Não houve diferenças significativas entre o grupo-controle e os experimentais com relação aos índices da série vermelha. Foram observados aumentos significativos (P<0,05) no número de neutrófilos, linfócitos e monócitos nos ratos dos grupos B e C, enquanto o número de plaquetas diminuiu. A concentração de glicose permaneceu inalterada em todos os grupos, mas foram observadas importantes alterações nos valores séricos de ureia e creatinina. Esses resultados mostraram que o veneno de escorpião comprometeu o funcionamento dos rins. Como demonstrado pelo aumento da atividade da amilase sérica e a redução dos níveis de insulina, a função pancreática também foi afetada.(AU)

ADMINISTRAÇÃO DA MELATONINA EXÓGENA SOBRE A HISTOFISIOLOGIA RENAL E ESTRESSE OXIDATIVO EM RATOS ADULTOS INDUZIDOS AO DIABETES

A nefropatia associada ao diabetes mellitus é uma das mais sérias e comuns complicações microvasculares do diabetes tipo 1 e tipo 2 e os seus efeitos nos rins são principalmente resultantes da hiperglicemia. O objetivo do trabalho foi avaliar se a administração da melatonina pode neutralizar os efeitos adversos da nefropatia diabética induzida pela estreptozotocina, melhorando diretamente características como função renal, pressão arterial e o estresse oxidativo. Para tanto, foram utilizados 50 ratos albinos, divididos nos seguintes grupos: GC: ratos sem indução ao diabetes; GD: ratos induzidos ao diabetes e tratados com placebo; GDM: ratos induzidos ao diabetes e tratados com melatonina na dosagem de 10mg/kg durante 20 dias; GDMS: ratos induzidos ao diabetes e tratados simultaneamente com melatonina; GDI: ratos induzidos ao diabetes e tratados com insulina na dose de 5U/dia durante 20 dias. Os resultados mostraram que a administração da melatonina simultaneamente a indução do diabetes foi capaz de produzir efeitos benéficos nas alterações encontradas nos animais diabéticos, atuando de maneira positiva ao reduzir o peso dos rins e o índice organossomático, tendência a redução dos valores hiperglicêmicos, proteção das células beta pancreáticas refletidos nos valores de insulina, recuperação dos níveis plasmáticos do óxido nítrico, bem como minimizou as alterações histológicas, reduzindo também o acúmulo de glicogênio e colágeno nos rins desses animais. Além disso, os valores de creatinina e uréia apresentaram-se equivalentes aos dos animais do grupo controle. Melatonina também reduziu os níveis de TBARS e a taxa de células apoptóticas. No entanto, não interferiu significativamente sobre os níveis da GSH, ganho de peso corporal e pressão arterial. Assim, concluimos que a administração da melatonina simultaneamente a indução do diabetes atuou de maneira benéfica sobre a histofisiologia renal de animais com o quadro de nefropatia diabética, comprovando sua capacidade antioxidante e protetora sobre os rins.

Nephropathy associated with diabetes mellitus is one of the most serious and common microvascular complications of type 1 diabetes and type 2 and its effects are primarily on the kidney resulting from hyperglycemia. The objective was to evaluate whether the administration of melatonin may neutralize the adverse effects of diabetic nephropathy streptozotocin-induced, improving directly characteristics as kidney function, blood pressure and oxidative stress. Therefore, 50 albino rats were divided into the following groups were used: GC: rats without inducing diabetes; GD: rats induced diabetes and treated with placebo; GDM: rats induced diabetes and treated with melatonin at a dose of 10mg/kg for 20 days; GDMS: rats induced diabetes and treated simultaneously with melatonin; GDI: and diabetes induced rats treated with insulin at a dose of 5 U/day for 20 days. The results showed that administration of melatonin simultaneously induction of diabetes was able to produce beneficial effects on the changes seen in diabetic animals, acting positively to reduce the weight of the kidneys and the organossomatic index, tend to reduce the hyperglycemic values, protection of pancreatic beta cells reflected in insulin values, recovery of plasma levels of nitric oxide, as well as minimized the histological changes also reduce the accumulation of glycogen and collagen kidney of these animals. Furthermore, the values of creatinine and urea showed to be comparable to those of the control group animals. Melatonin also reduced the TBARS and the rate of apoptotic cells. However, did not interfere significantly on the GSH levels, body weight gain and blood pressure. Thus, we conclude that the administration of melatonin simultaneously diabetes induction acted beneficially on renal histophysiology animals with diabetic nephropathy frame, proving its antioxidant capacity and protective on the kidneys.

Insulinoma canino: estudo retrospectivo de seis casos (2003-2012) / Canine insulinoma: retrospective study of 6 cases (2003-2012)

Os insulinomas são tumores malignos raros em cães, oriundos das células beta pancreáticas que produzeminsulina e levam a hipoglicemia. O objetivo do presente estudo retrospectivo foi descrever seiscasos de insulinoma canino. Os cães incluídos no estudo apresentavam faixa etária entre 7 e 16 anos,sendo 4 fêmeas e 2 machos. O diagnóstico baseou-se nos sinais clínicos e dosagem de insulina sérica porradioimunoensaio no momento de hipoglicemia (n=6), além da presença de massa pancreática por examede imagem (n=4). Todos os cães apresentaram como sinais iniciais a incoordenação, fraqueza e/ouconvulsões e a média de tempo até o diagnóstico foi de 2,2 meses. A hipoglicemia (média 34,67 ± 13,54mg/dL referência 70 110mg/dL) era a única alteração laboratorial presente e a hiperinsulinemia acimade 20 μu/mL (média 118 ± 75,11 μu/mL) se confirmou em todos dos cães. Apenas 4 apresentavamtumor visível no momento do diagnóstico. O exame histopatológico realizado em 3 cães confirmou ocaráter maligno dos tumores (carcinomas neuroendócrinos) e a avaliação imunohistoquímica de doiscasos demonstrou marcação positiva somente para insulina. Cães com sinais de fraqueza ou convulsãodevem ser sempre submetidos à avaliação glicêmica. Naqueles em que a hipoglicemia, mesmo que leve,for documentada, a dosagem de insulina sérica se faz necessária.(AU)

Insulinomas are rare malignant tumors in dogs, originating from pancreatic β cells that produceinsulin and lead to hypoglycemia. The aim of this retrospective study is to evaluate six cases ofcanine insulinomas. We included six diagnosed dogs aged between 7 and 16 years (4 females and 2males). The diagnosis was based on clinical signs associated with the measurement of serum insulinby radioimmunoassay at the time of hypoglycemia (n = 6), and the presence of pancreatic mass byimaging exams (n = 4). All dogs showed initial signs of lack of coordination, weakness, and / orseizures. The average time to diagnosis was 2.2 months. Hypoglycemia (mean 34.67 ± 13.54 mg/dL - Reference 70 110 mg/dL) was the only laboratory abnormality present and hyperinsulinemia above 20 μU/mL (mean 118 ± 75.11 μU/mL) was confirmed in all of the dogs. Only 4 dogs hadvisible tumor at the time of diagnosis. The histopathological examination confirmed the malignanttumors in 3 dogs (neuroendocrine carcinomas) and immunohistochemical evaluation of two casesshowed positive staining only for insulin. Dogs showing signs of weakness or seizure should alwaysbe evaluated for glucose levels. Those in whom hypoglycemia, even if mild, is documented, shouldcheck serum insulin levels.(AU)