Asiatic acid improves insulin secretion of β cells in type 2 diabetes through TNF- α/Mfn2 pathway / 浙江大学学报·医学版

OBJECTIVES@#To investigate the effects and molecular mechanisms of asiatic acid on β-cell function in type 2 diabetes mellitus (T2DM).@*METHODS@#The T2DM model was established by high fat diet and streptozotocin injection in ICR mice, and the effects of asiatic acid on glucose regulation were investigated in model mice. The islets were isolated from palmitic acid-treated diabetic mice. ELISA was used to detect the glucose-stimulated insulin secretion, tumor necrosis factor (TNF)-α and interleukin (IL)-6. ATP assay was applied to measure ATP production, and Western blotting was used to detect protein expression of mature β cell marker urocortin (Ucn) 3 and mitofusin (Mfn) 2. The regulatory effects of asiatic acid on glucose-stimulated insulin secretion (GSIS) and Ucn3 expression were also investigated after siRNA interference with Mfn2 or treatment with TNF-α.@*RESULTS@#Asiatic acid with the dose of 25 mg·kg－1·d－1 had the best glycemic control in T2DM mice and improved the homeostasis model assessment β index. Asiatic acid increased the expression of Mfn2 and Ucn3 protein and improved the GSIS function of diabetic β cells in vitro and in vivo (both P<0.05). Moreover, it improved the ATP production of islets of T2DM mice in vitro (P<0.05). Interfering Mfn2 with siRNA blocked the up-regulation of Ucn3 and GSIS induced by asiatic acid. Asiatic acid inhibited islet TNF-α content and increased Mfn2 and Ucn3 protein expression inhibited by TNF-α.@*CONCLUSIONS@#Asiatic acid improves β cell insulin secretion function in T2DM mice by maintaining the β cell maturity, which may be related to the TNF-α/Mfn2 pathway.

The differences in homeostasis model assessment values in type 2 diabetic patients with different lengths of history of diabetes

ABSTRACT Objective Type 2 diabetes (T2DM) is characterized by the progressive deterioration of pancreatic islet β-cell function over time and insulin resistance. Knowing more about the differences in pancreatic islet function in T2DM patients who have had diabetes for different lengths of time can help improve therapy for T2DM. Subjects and methods We conducted a cross-sectional study to compare islet β-cell function and insulin resistance in T2DM patients (n = 3,254) who had had diabetes for different lengths of time and those in normal controls (n = 794) using ANOVA and LSD analysis. Results We found that compared with that in normal controls, HOMA-β in T2DM patients with a history of diabetes of less than 1 year was lower (approximately 52% of that of normal controls, p = 0.003), while HOMA-IR in these patients was higher (approximately 50% of that of normal controls, p = 0.007). Compared with that in other diabetic patients, HOMA-β in patients with a history of diabetes of more than 30 years was the lowest. HOMA-IR in patients with a history of diabetes of between 20 and 30 years was lower than that in other diabetic patients (p < 0.05). Conclusions There were obvious decreases in HOMA-β and increases in HOMA-IR in T2DM patients with a history of diabetes of less than 1 year compared with those in normal controls. Therefore, early screening and intervention for T2DM might help improve islet function and delay the progression of diabetes.

Duodenal-jejunal bypass normalizes pancreatic islet proliferation rate and function but not hepatic steatosis in hypothalamic obese rats

Modifications in life-style and/or pharmacotherapies contribute to weight loss and ameliorate the metabolic profile of diet-induced obese humans and rodents. Since these strategies fail to treat hypothalamic obesity, we have assessed the possible mechanisms by which duodenal-jejunal bypass (DJB) surgery regulates hepatic lipid metabolism and the morphophysiology of pancreatic islets, in hypothalamic obese (HyO) rats. During the first 5 days of life, male Wistar rats received subcutaneous injections of monosodium glutamate (4 g/kg body weight, HyO group), or saline (CTL). At 90 days of age, HyO rats were randomly subjected to DJB (HyO DJB group) or sham surgery (HyO Sham group). HyO Sham rats were morbidly obese, insulin resistant, hypertriglyceridemic and displayed higher serum concentrations of non-esterified fatty acids (NEFA) and hepatic triglyceride (TG). These effects were associated with higher expressions of the lipogenic genes and fatty acid synthase (FASN) protein content in the liver. Furthermore, hepatic genes involved in β-oxidation and TG export were down-regulated in HyO rats. In addition, these rats exhibited hyperinsulinemia, β-cell hypersecretion, a higher percentage of islets and β-cell area/pancreas section, and enhanced nuclear content of Ki67 protein in islet-cells. At 2 months after DJB surgery, serum concentrations of TG and NEFA, but not hepatic TG accumulation and gene and protein expressions, were normalized in HyO rats. Insulin release and Ki67 positive cells were also normalized in HyO DJB islets. In conclusion, DJB decreased islet-cell proliferation, normalized insulinemia, and ameliorated insulin sensitivity and plasma lipid profile, independently of changes in hepatic metabolism.

A digital volumetric tomography (DVT) study in the mandibular molar region for miniscrew placement during mixed dentition

OBJECTIVE: To assess bone thickness for miniscrew placement in the mandible during mixed dentition by using digital volumetric tomograph (DVT). MATERIAL AND METHODS: A total of 15 healthy patients aged 8-10 years old, with early exfoliated mandibular second deciduous molar, were included. DVT images of one quadrant of the mandible were obtained using Kodak extraoral imaging systems and analyzed by Kodak dental imaging software. The error of the method (EM) was calculated using Dahlberg's formula. Mean and standard deviation were calculated at 6 and 8 mm from the cementoenamel junction (CEJ).Paired t-test was used to analyze the measurements. RESULTS: Buccal cortical bone thickness, mesiodistal width and buccolingual bone depth at 6 mm were found to be 1.73 + 0.41, 2.15 + 0.49 and 13.18 + 1.22 mm, respectively; while at 8 mm measurements were 2.42 + 0.34, 2.48 + 0.33 and 13.65 + 1.25 mm, respectively. EM for buccal cortical bone thickness, mesiodistal width and buccolingual bone depth was 0.58, 0.40 and 0.48, respectively. The difference in measurement at 6 and 8 mm for buccal cortical plate thickness (P < 0.05) and buccolingual bone thickness (P < 0.05) was found to be significant, whereas for mesiodistal width it was insignificant (P > 0.05). CONCLUSION: Bone thickness measurement has shown promising evidence for safe placement of miniscrews in the mandible during mixed dentition. The use of miniscrew is the best alternative, even in younger patients. .

OBJETIVO: avaliar, por meio de tomografia volumétrica digital (TVD), a espessura óssea necessária para a instalação de mini-implante na arcada inferior durante a fase de dentição mista. MÉTODOS: um total de 15 pacientes saudáveis, com idades entre 8 e 10 anos, com segundo molar inferior decíduo irrompido recentemente, foram incluídos no presente estudo. Imagens de TVD da hemiarcada inferior foram obtidas utilizando sistemas de imagens extrabucais Kodak. As imagens foram analisadas por meio do programa de imagens Kodak. O erro do método (EM) foi calculado utilizando a fórmula de Dahlberg. Médias e desvios-padrão foram calculados de 6 a 8mm aquém da junção amelocementária. O teste t foi utilizado para a análise das medidas. RESULTADOS: a espessura do osso cortical vestibular, largura mesiodistal e profundidade óssea vestibulolingual, a 6mm, foram de 1,73 + 0,41; 2,15 + 0,49; e 13,18 + 1,22 mm, respectivamente. Já a 8mm, os valores foram de 2,42 + 0,34; 2,48 + 0,33; e 13,65 + 1,25mm. O EM para a espessura do osso cortical vestibular, largura mesiodistal e profundidade óssea vestibulolingual foi de 0,58, 0,40 e 0,48mm, respectivamente. A diferença entre as medidas a 6 e 8mm para a espessura do osso cortical vestibular (p < 0,05) e a espessura óssea vestibulolingual (p < 0,05) foi significativa, embora não tenha sido significativa para a largura mesiodistal (p < 0,05). CONCLUSÃO: a mensuração da espessura óssea demonstra evidências promissoras para a segura instalação de mini-implantes na arcada inferior e na fase de dentição mista. O uso de mini-implantes tem se mostrado a melhor alternativa, mesmo nos casos de pacientes mais jovens. .

Uncoupling protein-2 mRNA expression in mice subjected to intermittent hypoxia / Expressão do mRNA da uncoupling protein-2 em camundongos submetidos à hipóxia intermitente

Objective: To investigate the effect of intermittent hypoxia-a model of obstructive sleep apnea (OSA)-on pancreatic expression of uncoupling protein-2 (UCP2), as well as on glycemic and lipid profiles, in C57BL mice. Methods: For 8 h/day over a 35-day period, male C57BL mice were exposed to intermittent hypoxia (hypoxia group) or to a sham procedure (normoxia group). The intermittent hypoxia condition involved exposing mice to an atmosphere of 92% N and 8% CO2 for 30 s, progressively reducing the fraction of inspired oxygen to 8 ± 1%, after which they were exposed to room air for 30 s and the cycle was repeated (480 cycles over the 8-h experimental period). Pancreases were dissected to isolate the islets. Real-time PCR was performed with TaqMan assays. Results: Expression of UCP2 mRNA in pancreatic islets was 20% higher in the normoxia group than in the hypoxia group (p = 0.11). Fasting serum insulin was higher in the hypoxia group than in the normoxia group (p = 0.01). The homeostasis model assessment of insulin resistance indicated that, in comparison with the control mice, the mice exposed to intermittent hypoxia showed 15% lower insulin resistance (p = 0.09) and 21% higher pancreatic β-cell function (p = 0.01). Immunohistochemical staining of the islets showed no significant differences between the two groups in terms of the area or intensity of α- and β-cell staining for insulin and glucagon. Conclusions: To our knowledge, this is the first report of the effect of intermittent hypoxia on UCP2 expression. Our findings suggest that UCP2 regulates insulin production in OSA. Further study of the role that UCP2 plays in the glycemic control of OSA patients is warranted. .

Objetivo: Investigar o efeito da hipóxia intermitente com um modelo de apneia obstrutiva do sono (AOS) sobre a expressão de uncoupling protein-2 (UCP2), assim como sobre perfis glicêmicos e lipídicos, em camundongos C57BL. Métodos: Camundongos C57BL machos foram expostos a hipóxia intermitente ou hipóxia simulada (grupo controle) 8 h/dia durante 35 dias. A condição de hipóxia intermitente envolveu a exposição dos camundongos a uma atmosfera de 92% de N e 8% de CO2 por 30 s, com redução progressiva de fração de O2 inspirado até 8 ± 1%, seguida por exposição a ar ambiente por 30 s e repetições do ciclo (480 ciclos no período experimental de 8 h). Os pâncreas foram dissecados para isolar as ilhotas. Foi realizada PCR em tempo real utilizando o método TaqMan. Resultados: A expressão do mRNA da UCP2 nas ilhotas pancreáticas foi 20% maior no grupo controle que no grupo hipóxia (p = 0,11). A insulina sérica de jejum foi maior no grupo hipóxia do que no grupo controle (p = 0,01). O modelo de avaliação da homeostase de resistência à insulina indicou que, em comparação com os camundongos controle, aqueles expostos à hipóxia intermitente apresentaram 15% menor resistência à insulina (p = 0,09) e 21% maior função das células beta (p = 0,01). A coloração das ilhotas pancreáticas por imuno-histoquímica não mostrou diferenças significativas entre os grupos em termos da área ou da intensidade das células alfa e beta, marcadas por insulina e glucagon. Conclusões: Segundo nosso conhecimento, esta é a primeira descrição do efeito da hipóxia intermitente sobre a expressão da UCP2. Nossos achados sugerem que UCP2 regula a produção de insulina na AOS. Futuras investigações sobre o papel da UCP2 no controle glicêmico em pacientes com AOS são justificadas. .

Assessment of nursing care using indicators generated by software / Avaliação da assistência de enfermagem utilizando indicadores gerados por um software / Evaluación de la asistencia de enfermería utilizando indicadores generados por un software

OBJECTIVE: to analyze the efficacy of the Nursing Process in an Intensive Care Unit using indicators generated by software. METHOD: cross-sectional study using data collected for four months. RNs and students daily registered patients, took history (at admission), performed physical assessments, and established nursing diagnoses, nursing plans/prescriptions, and assessed care delivered to 17 patients using software. Indicators concerning the incidence and prevalence of nursing diagnoses, rate of effectiveness, risk diagnoses, and rate of effective prevention of complications were computed. RESULTS: the Risk for imbalanced body temperature was the most frequent diagnosis (23.53%), while the least frequent was Risk for constipation (0%). The Risk for Impaired skin integrity was prevalent in 100% of the patients, while Risk for acute confusion was the least prevalent (11.76%). Risk for constipation and Risk for impaired skin integrity obtained a rate of risk diagnostic effectiveness of 100%. The rate of effective prevention of acute confusion and falls was 100%. CONCLUSION: the efficacy of the Nursing Process using indicators was analyzed because these indicators reveal how nurses have identified patients' risks and conditions, and planned care in a systematized manner. .

OBJETIVO: analisar a eficácia do Processo de Enfermagem em uma Unidade de Terapia Intensiva, utilizando indicadores gerados por um software. MÉTODO: estudo transversal, cujos dados foram coletados durante quatro meses. Enfermeiros e acadêmicos realizaram, diariamente, cadastro e anamnese (na admissão), exame físico, diagnósticos de enfermagem, planejamento/prescrição de enfermagem e avaliação da assistência de 17 pacientes, utilizando um software. Calculou-se os indicadores incidência e prevalência de diagnósticos de enfermagem, taxa de efetividade diagnóstica de risco e taxa de efetividade na prevenção de complicações. RESULTADOS: o Risco de desequilíbrio na temperatura corporal foi o diagnóstico mais incidente (23,53%) e o menos incidente foi o Risco de constipação (0%). O Risco de integridade da pele prejudicada foi prevalente em 100% dos pacientes, enquanto o Risco de confusão aguda foi o menos prevalente (11,76%). Risco de constipação e Risco de integridade da pele prejudicada obtiveram taxa de efetividade diagnóstica de risco de 100%. A taxa de efetividade na prevenção de confusão aguda e de queda foi de 100%. CONCLUSÃO: analisou-se a eficácia do Processo de Enfermagem utilizando indicadores, pois retratam como o enfermeiro tem identificado os problemas e riscos do paciente, e planejado a assistência de forma sistematizada. .

OBJETIVO: analizar la eficacia del Proceso de Enfermería en una Unidad de Terapia Intensiva, utilizando indicadores generados por un software. MÉTODO: estudio transversal, cuyos datos fueron recolectados durante cuatro meses. Enfermeros y académicos realizaron, diariamente, registro y anamnesis (en la admisión), examen físico, diagnósticos de enfermería, planificación/prescripción de enfermería y evaluación de la asistencia en 17 pacientes, utilizando un software. Se calculó los indicadores incidencia y prevalencia de diagnósticos de enfermería, la tasa de efectividad diagnóstica de riesgo y la tasa de efectividad en la prevención de complicaciones. RESULTADOS: el Riesgo de desequilibrio en la temperatura corporal fue el diagnóstico más prevalente (23,53%) y el menos prevalente fue el Riesgo de constipación (0%). El Riesgo de integridad de la piel perjudicada fue prevalente en 100% de los pacientes, en cuanto el Riesgo de confusión aguda fue el menos prevalente (11,76%). El Riesgo de constipación y el Riesgo de integridad de la piel perjudicada obtuvieron una tasa de efectividad diagnóstica de riesgo de 100%. La tasa de efectividad en la prevención de confusión aguda y de caída fue de 100%. CONCLUSIÓN: se analizó la eficacia del Proceso de Enfermería utilizando indicadores, ya que retratan cómo el enfermero ha identificado los problemas y riesgos del paciente, y planificado la asistencia de forma sistematizada. .

A low-protein diet during pregnancy prevents modifications in intercellular communication proteins in rat islets

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Síndrome de Stevens-Johnson e Necrólise Epidérmica Tóxica em um hospital do Distrito Federal / Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis in a hospital in Distrito Federal / Síndrome de Stevens-Johnson y necrólisis epidérmica tóxica en un hospital en Distrito Federal

Objetivou-se analisar as características demográficas e clínicas dos clientes diagnosticados com Síndrome de Stevens Johnson (SSJ) e Necrólise Epidérmica Tóxica (NET), bem como identificar as ações dos profissionais de saúde para o manejo das Reações Adversas a Medicamentos (RAM) em um hospital público do Distrito Federal. Pesquisa descritiva, retrospectiva, com abordagem quantitativa. Dados coletados em todos os prontuários de 22 clientes internados de janeiro de 2005 a setembro de 2012. Análise mediante estatística descritiva. Houve aumento gradativo de casos, com maior número nos anos de 2007 e 2012. Dos casos analisados, 9 foram diagnosticados com NET e 7 com SSJ; predominaram as mulheres (14) e a faixa etária de 21 aos 40 anos (10); 21 obtiveram cura. Os fármacos associados a RAM mais frequentes foram os antiepilépticos (10). Observou-se fragilidade nos registros clínicos nos prontuários e nas ações de monitoramento de RAM no serviço estudado.

This study aimed to analyze demographic and clinical aspects of patients diagnosed with Stevens Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN), as well as identifying the actions of health professionals for the management of Adverse Drug Reactions (ADR) in a public hospital in Distrito Federal, Brazil. A descriptive and retrospective research was held, with quantitative approach. Data collected from all the records of 22 patients admitted with diagnosed with SJS and TEN, from January 2005 to September 2012. Data were analyzed using descriptive statistics. Of these cases, 9 were diagnosed with NET and 7, with SJS; there were more females (14); aged from 21 to 40 years (10); 21 were cured; the drugs more used were the antiepileptic ones (10). Fragility in clinical registers and in the actions to monitor the cases of ADR in this health service was observed.

Este estudio tuvo como objetivo analizar aspectos demográficos y clínicos de clientes con diagnóstico de Síndrome de Stevens Johnson (SSJ) y Necrólisis Epidérmica Tóxica (NET), así como la identificación de las acciones de los profesionales de la salud para el manejo de reacciones adversas a medicamentos (RAM) en un hospital público del Distrito Federal. Se realizó investigación descriptiva, retrospectiva con enfoque cuantitativo. Datos recogidos de prontuarios clínicos de los 22 clientes ingresados con diagnóstico de SJS y NET, de enero de 2005 a septiembre de 2012. Fueron analizados utilizando estadística descriptiva. De estos casos, 9 fueron diagnosticados con NET, 7 con SJS; había más mujeres (14); edad entre 21 y 40 años (10); 21 se curaron; predominaran los antiepilépticos (10). Fue observado que hay fragilidad en registros clínicos en los prontuarios y en las acciones de monitoreo de las RAM en este servicio de salud.

Assessment of Bone Healing in Rabbit Calvaria Grafted with Three Different Biomaterials

This study evaluated the bone regeneration process in rabbit calvaria induced by three types of biomaterials: two xenogenous, consisting of deproteinized bovine bone, while the other was alloplastic, based on biphasic calcium phosphate. Five New Zealand white rabbits weighing between 2,900 and 3,500 g were submitted to four standard 8 mm-diameter perforations at the parietal bone. Three perforations were filled with three grafts and biomaterials, two of them received bovine Bio-Oss(r) and Endobon(r) Xenograft Granules, and the other consisted of fully alloplastic Straumann(r) Bone Ceramic. The fourth remaining cavity was used as control with coagulum. After eight weeks, the animals were sacrificed, and the samples were prepared for morphometric and qualitative analysis. The cavities filled with alloplastic biomaterials showed higher percentages of newly formed bone (p<0.05), while the cavities with xenogenous biomaterials showed higher amount of residual graft (p<0.05). Although the results showed greater bone formation with Straumann(r) Bone Ceramic, further studies are required to prove which is the more effective biomaterial for bone induction process.

Este estudo avaliou o processo de reparação óssea induzida por três biomateriais, dois de origem xenógena constituído de osso bovino desproteinizado e um aloplástico à base de fosfato de cálcio bifásico, em calota craniana de coelhos. Em cinco coelhos brancos da Nova Zelândia com peso entre 2.900 e 3.500 g, foram realizadas quatro perfurações padronizadas de 8 mm de diâmetro nos ossos parietais e enxertados dois biomateriais de origem bovina: Bio-Oss(r) e Endobon(r) Xenograft Granules e um totalmente aloplástico: Straumann(r)Bone Ceramic. Uma cavidade permaneceu com coágulo e foi utilizado como controle. Após oito semanas os animais foram sacrificados e as amostras preparadas para análise morfométrica e qualitativa. Os resultados mostraram que as cavidades preenchidas com o biomaterial aloplástico apresentaram percentualmente maior quantidade de osso neoformado (p<0,05). Apesar dos resultados mostrarem maior neoformação óssea pelo Straumann(r)Bone Ceramic, há a necessidade de mais estudos para se comprovar qual biomaterial é mais efetivo no processo de indução óssea.

Bloqueadores do sistema renina-angiotensina em ilhotas pancreáticas e fígado na obesidade induzida por dietas em camundongos / Renin-angiotensin system blockers in pancreatic islets and liver on diet-induced obesity in mice

As associações entre obesidade, doença hepática gordurosa não alcoólica (NAFLD) e diabetes mellitus tipo 2 (DM2) são bem estabelecidas, e o sistema renina-angiotensina (SRA) pode proporcionar uma ligação entre eles. O bloqueio do SRA em diferentes níveis pode estar relacionado a respostas na resistência à insulina, remodelagem do pâncreas e do fígado em um modelo de obesidade induzida por dieta. Camundongos C57BL/6 foram alimentados com uma dieta hiperlipídica (HF) durante oito semanas e depois tratados com alisquireno (50 mg/kg/dia), enalapril (30 mg/kg/dia) ou losartana (10 mg/kg/dia) por um período adicional de seis semanas. As drogas foram incorporadas na dieta. Avaliou-se a massa corporal (MC), pressão arterial, consumo e gasto energético (GE), metabolismo da glicose e lipídico, histopatologia pancreática e hepática, análise hormonal, imunohistoquímica, perfil gênico e/ou proteico do SRA no pâncreas, gliconeogênese hepática, sinalização da insulina, oxidação e acúmulo lipídico. Todos os inibidores do SRA reduziram significativamente o aumento da pressão arterial nos camundongos alimentados com dieta HF. O tratamento com enalapril, mas não alisquireno ou losartana, reduziu o ganho de MC e a ingestão alimentar; aumentou o GE; amenizou a intolerância à glicose e resistência à insulina; melhorou a massa de células alfa e beta; impediu a redução da adiponectina plasmática e restaurou a sensibilidade à leptina. Além disso, o tratamento com enalapril melhorou a expressão proteica nas ilhotas pancreáticas de Pdx1, GLUT2, ECA2 e do receptor Mas. O tratamento com losartana apresentou uma elevação na expressão proteica de AT2R no pâncreas...

The associations between obesity, NAFLD (non-alcoholic fatty liver disease) and diabetes are well established, and the renin–angiotensin system (RAS) may provide a link among them. . The blocking of the RAS at different levels may be related to responses on insulin resistance, remodeling of the pancreas and liver in a model of diet-induced obesity. Mice (C57BL/6) were fed on a high-fat (HF) diet for 8 weeks and then treated with aliskiren (50 mg/kg/day), enalapril (30 mg/kg/day) or losartan (10 mg/kg/day) for an additional 6 weeks. The drugs were incorporated into the diet. We assessed body mass (BM), blood pressure, energy intake and expenditure (EE), glucose and lipid metabolism, pancreatic and hepatic histopathology, hormonal analysis, immunohistochemistry, the expression profile of genes and/or proteins affecting pancreas RAS, hepatic gluconeogenesis, insulin signaling and lipid oxidation and accumulation. All RAS inhibitors significantly attenuated the increased blood pressure in mice fed a HF diet. Treatment with enalapril, but not aliskiren or losartan, significantly attenuated BM gain, increased EE, enhanced the glucose intolerance and insulin resistance; improved the alpha and beta cell mass; prevented the reduction of plasma adiponectin and restored leptin sensibility. Furthermore, enalapril treatment improved the protein expression of the pancreatic islet Pdx1, GLUT2, ACE2 and Mas receptors. Losartan treatment showed the greatest AT2R expression in the pancreas. In the liver, the enalapril administration improved hepatic steatosis, triglycerides and prevented the increase hepatic protein levels of PEPCK, G6Pase and GLUT2...

A Case of Alpha-cell Nesidioblastosis and Hyperplasia with Multiple Glucagon-producing Endocrine Cell Tumor of the Pancreas / 대한소화기학회지

Nesidioblastosis is a term used to describe pathologic overgrowth of pancreatic islet cells. It also means maldistribution of islet cells within the ductules of exocrine pancreas. Generally, nesidioblastosis occurs in beta-cell and causes neonatal hyperinsulinemic hypoglycemia or adult noninsulinoma pancreatogenous hypoglycemia syndrome. Alpha-cell nesidioblastosis and hyperplasia is an extremely rare disorder. It often accompanies glucagon-producing marco- and mircoadenoma without typical glucagonoma syndrome. A 35-year-old female was referred to our hospital with recurrent acute pancreatitis. On radiologic studies, 1.5 cm sized mass was noted in pancreas tail. Cytological evaluation with EUS-fine-needle aspiration suggested serous cystadenoma. She received distal pancreatectomy. The histologic examination revealed a 1.7 cm sized neuroendocrine tumor positive for immunohistochemical staining with glucagon antibody. Multiple glucagon-producing micro endocrine cell tumors were scattered next to the main tumor. Additionally, diffuse hyperplasia of pancreatic islets and ectopic proliferation of islet cells in centroacinar area, findings compatible to nesidioblastosis, were seen. These hyperplasia and almost all nesidioblastic cells were positive for glucagon immunochemistry. Even though serum glucagon level still remained higher than the reference value, she has been followed-up without any evidence of recurrence or hormone related symptoms. Herein, we report a case of alpha-cell nesidioblastosis and hyperplasia combined with glucagon-producing neuroendocrine tumor with literature review.

Reduction of lns-1 gene expression and tissue insulin levels in n5-STZ rats

Objective: The high global incidence of type 2 diabetes has challenged researchers to establish animal models that resemble the chronic stage observed in type 2 diabetes patients. One such model is induced by neonatal streptozotocin (n-STZ) administration to rat pups at 0, 2, or 5 days after birth. In this study, we assessed lns-1 gene expression and tissue insulin levels as well as serum concentration of glucose and insulin, insulin resistance, and histological changes of the islets of Langerhans in n5-STZ rats after 20-weeks post-induction. Methods: Wistar rat pups were randomly distributed into a control group and a streptozotocin-induced group. Experimental induction involved a single intraperitoneal injection of streptozotocin (150 mg/kg) into neonates at five days after birth. Results: At 20 weeks post-induction, streptozotocin-induced rats exhibited increased serum glucose levels, reduced serum insulin levels, impaired glucose metabolism and insulin resistance compared to control rats. Histologically, streptozotocin-induced rats exhibited atrophic islets, vacuolization, and significantly fewer insulin-positive cells. lns-1 gene expression was significantly decreased in n5-STZ rats in comparison to the control group. Conclusion: Our findings support that the n5-STZ model 20 weeks post-induction represents an appropriate experimental tool to study T2D and to evaluate novel therapeutic agents and targets that involve insulin gene expression and secretion, as well as complications caused by chronic diabetes.

Functional improvement of porcine neonatal pancreatic cell clusters via conformal encapsulation using an air-driven encapsulator

Transplantation of islet cells into diabetic patients is a promising therapy, provided that the islet cells are able to evade host immune rejection. With improved islet viability, this strategy may effectively reverse diabetes. We applied 2% calcium alginate to generate small and large capsules to encapsulate porcine neonatal pancreatic cell clusters (NPCCs) using an air-driven encapsulator. After encapsulation, the viability was assessed at 1, 4, 7, 14 and 28 days and secretion of functional insulin in response to glucose stimulation were tested at days 14 and 28. Selective permeability of the small alginate capsules was confirmed using various sizes of isothiocyanate-labeled dextran (FITC-dextran). Encapsulation of NPCCs was performed without islet protrusion in the small and large capsules. The viability of NPCCs in all experimental groups was greater than 90% at day 1 and then gradually decreased after day 7. The NPCCs encapsulated in large capsules showed significantly lower viability (79.50 +/- 2.88%) than that of naive NPCCs and NPCCs in small capsule (86.83 +/- 2.32%, 87.67 +/- 2.07%, respectively) at day 7. The viability of naive NPCCs decreased rapidly at day 14 (75.67 +/- 1.75%), whereas the NPCCs encapsulated in small capsules maintained (82.0 +/- 2.19%). After 14 and 28 days NPCCs' function in small capsules (2.67 +/- 0.09 and 2.13 +/- 0.09) was conserved better compared to that of naive NPCCs (2.04 +/- 0.25 and 1.53 +/- 0.32, respectively) and NPCCs in large capsules (2.04 +/- 0.34 and 1.13 +/- 0.10, respectively), as assessed by a stimulation index. The small capsules also demonstrated selective permeability. With this encapsulation technique, small capsules improved the viability and insulin secretion of NPCCs without islet protrusion.

Insulin signaling proteins in pancreatic islets of insulin-resistant rats induced by glucocorticoid

Chronic administration of glucocorticoids induces insulin resistance that is compensated by an increase in p-cell function and mass. Since insulin signaling is involved in the control of p-cell function and mass, we investigated the content of insulin pathway proteins in pancreatic islets. Rats were made insulin resistant by daily administration of dexamethasone (1mg/kg, b.w., i.p.) for 5 consecutive days (DEX), whilst control rats received saline (CTL). Circulating insulin and insulin released from isolated islets were measured by radioimmunoassay whereas the content of proteins was analyzed by Western blotting. DEX rats were hyperinsulinemic and exhibited augmented insulin secretion in response to glucose (P < 0.01). The IRa-subunit, IRS-1, Shc, AKT, p-p70S6K, ERK1/2, p-ERK1/2, and glucocorticoid receptor protein levels were similar between DEX and CTL islets. However, the IRp-subunit, p-IRp-subunit, IRS-2, PI3-K, p-AKT and p70S6K protein contents were increased in DEX islets (P < 0.05). We conclude that IRS-2 may have a major role, among the immediate substrates of the insulin receptor, to link activated receptors to downstream signaling components related to islet function and growth in this insulin-resistant rat model.

Beneficial effects of exercise training (treadmill) on insulin resistance and nonalcoholic fatty liver disease in high-fat fed C57BL/6 mice

C57BL/6 mice develop signs and symptoms comparable, in part, to the human metabolic syndrome. The objective of the present study was to evaluate the effects of exercise training on carbohydrate metabolism, lipid profile, visceral adiposity, pancreatic islet alterations, and nonalcoholic fatty liver disease in C57BL/6 mice. Animals were fed one of two diets during an 8-week period: standard (SC, N = 12) or very high-fat (HF, N = 24) chow. An exercise training protocol (treadmill) was then established and mice were divided into SC and HF sedentary (SC-Sed, HF-Sed), exercised groups (SC-Ex, HF-Ex), or switched from HF to SC (HF/SC-Sed and HF/SC-Ex). HF/HF-Sed mice had the greatest body mass (65 percent more than SC/SC-Sed; P < 0.0001), and exercise reduced it by 23 percent (P < 0.0001). Hepatic enzymes ALP (+80 percent), ALT (+100 percent) and AST (+70 percent) were higher in HF/HF mice than in matched SC/SC. Plasma insulin was higher in both the HF/HF-Sed and HF/SC-Sed groups than in the matched exercised groups (+85 percent; P < 0.001). Pancreatic islets, adipocytes and liver structure were greatly affected by HF, ultimately resulting in islet â-cell hypertrophy and severe liver steatosis. The HF group had larger islets than the SC/SC group (+220 percent; P < 0.0001), and exercise significantly reduced liver steatosis and islet size in HF. Exercise attenuated all the changes due to HF, and the effects were more pronounced in exercised mice switched from an HF to an SC diet. Exercise improved the lipid profile by reducing body weight gain, visceral adiposity, insulin resistance, islet alterations, and fatty liver, contributing to obesity and steatohepatitis control.

role of nitric oxide synthase in post-operative hyperglycaemia

Post-operative hyperglycaemia is important with regard to outcomes of surgical operations. It affects postoperative morbidity, length of hospital stay, and mortality. Poor peri-operative blood glucose control leads to a higher risk of post-operative complication. Insulin resistance as a cause of post-operative hyperglycaemia has been blamed for some time. Nitric Oxide [NO] is produced by nitric oxide synthase [NOS] isoenzymes. Inducible nitric oxide synthase [iNOS] is not a normal cellular constitute. It is expressed by cytokines and non-cytokines e.g. fasting, trauma, intravenous glucose, and lipid infusion, which are encountered in surgical operations. Review of current published data on postoperative hyperglycaemia was completed. Our studies and others were explored for the possible role of NO in this scenario. Induction and expression of iNOS enzyme in pancreatic islet cells is included in the chaotic postoperative blood glucose control. The high concentrations of iNOS derived NO are toxic to pancreatic p-cells and may inhibit insulin secretion postoperatively. Hence, current peri-operative management is questionable regarding post-operative hyperglycaemia and necessitates development of a new strategy

siRNA specific to Pdx-1 disturbed the formation of the islet in early zebrafish embryos / 华中科技大学学报（医学）（英德文版）

Pdx-1, an important transcription factor highlighting in the early pancreatic development, islet functions and pancreatic disorders, needs to be more investigated in zebrafish, and siRNA is still seldom applied in zebrafish embryo-related research. Our aim was to explore the role of pdx-1 in pancreatic development of zebrafish embryos by using siRNA approach. Microinjection, reverse transcriptase-PCR (RT-PCR), in situ hybridization and immunofluorescent staining were used in this research, and the morphology of the islet in normal zebrafish embryos, and in those treated with the siRNA specific to pdx-1 (siPDX-1) or siGFP was observed and compared. The expression of pdx-1 was detected in the stages of 1-cell, 2-cell, 4-cell, 8-cell, 16-cell, 16-hour by RT-PCT. The in situ hybridization and immunofluorescent staining results showed that siPDX-1 disturbed the formation of the islet in zebrafish embryos. Pdx-1 played multiple roles in maintaining the phenotype of the islet during embryogenesis in zebrafish.

A Protective Role for Heme Oxygenase-1 in INS-1 Cells and Rat Islets that are Exposed to High Glucose Conditions

Heme oxygenase-1 (HO-1) has been described as an inducible protein that is capable of cytoprotection via radical scavenging and the prevention of apoptosis. Chronic exposure to hyperglycemia can lead to cellular dysfunction that may become irreversible over time, and this process has been termed glucose toxicity. Yet little is known about the relation between glucose toxicity and HO-1 in the islets. The purposes of the present study were to determine whether prolonged exposure of pancreatic islets to a supraphysiologic glucose concentration disrupts the intracellular balance between reactive oxygen species (ROS) and HO-1, and so this causes defective insulin secretion; we also wanted to evaluate a protective role for HO-1 in pancreatic islets against high glucose levels. The intracellular peroxide levels of the pancreatic islets (INS-1 cell, rat islet) were increased in the high glucose media (30 mM glucose or 50 mM ribose). The HO-1 expression was induced in the INS-1 cells by the high glucose levels. Both the HO-1 expression and glucose stimulated insulin secretion (GSIS) was decreased simultaneously in the islets by treatment of the HO-1 antisense. The HO-1 was upregulated in the INS-1 cells by hemin, an inducer of HO-1. And, HO-1 upregulation induced by hemin reversed the GSIS in the islets at a high glucose condition. These results suggest HO-1 seems to mediate the protective response of pancreatic islets against the oxidative stress that is due to high glucose conditions.

Adenoviral mediated hepatocyte growth factor gene attenuates hyperglycemia and beta cell destruction in overt diabetic mice

Hepatocyte growth factor (HGF) is a potent mitogen and promoter of proliferation of insulin producing beta cells of pancreatic islets. To study the role of HGF, an adenoviral vector carrying the human HGF (Ad.hHGF) gene was transfected into the streptozotocin-induced diabetic mice and evaluated the effect on the blood glucose metabolism and the insulin-secreting beta cells of pancreatic islets. Ad.hHGF gene transfection resulted in amelioration of hyperglycemia and prolongation of survival period in the diabetic mice. Concomitantly adenoviral- mediated hHGF gene therapy slightly increased serum insulin concentration and the expression of insulin in the pancreatic islet. Although the proliferation of beta-cell mass was not noticeable, the beneficial effect of HGF is significant to an almost deteriorated pancreatic islets. Taken together, these data suggest that the Ad.hHGF gene therapy into diabetic mice may prevent the further destruction and present as a beneficial remedy for type 1 diabetic patients.