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Type 1 diabetes mellitus (T1DM) is an organ-specific disease characterized by autoimmune damage to pancreatic β cells. Insulin therapy is the most basic and important treatment for T1DM, but insulin therapy cannot fundamentally terminate or improve the main cause of T1DM, namely the disorder of the immune regulation mechanism. With the advancement of science and technology, the continuous development of new insulin and hypoglycemic drugs has provided better means for glycemic control. Pancreas transplantation, islet transplantation, immunotherapy, and cell therapy have provided hope for the prevention or reversal of T1DM. It is of great significance to understand the current situation and future of new technologies for T1DM treatment for the research and management of T1DM patients.
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Since the 1970s， patients with chronic pancreatitis （CP） have benefited from total pancreatectomy with autologous islet cell transplantation （TPAIT）. With the continuous development of surgical techniques and perioperative management over the past few decades， there have been improvements in islet cell function， insulin independence rate， and the survival rate of patients. This article summarizes the preoperative indications for TPAIT， the development of surgical operations， postoperative management and monitoring， and prognosis， so as to help clinicians learn more about TPAIT.
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Introdução: Os tumores neuroendócrinos pancreáticos são considerados raros. Eles são classificados em funcionantes e não funcionantes. Objetivo: Definir e classificar tumores neuroendócrinos pancreáticos de acordo com sua avaliação histopatológica e imunoistoquímica, associado aos critérios diagnósticos. Método: Trata-se de revisão narrativa sobre publicações encontradas no PubMed, SciELO e Google Acadêmico. Resultados: Esses tumores podem ser bem ou pouco diferenciados e apresentam características microscópicas distintas. As células bem diferenciadas têm formato pequeno, núcleos uniformes redondos ou ovais, citoplasma finamente granular indicando forte capacidade secretória e mantêm a estrutura organoide. A presença de necrose tumoral, atividade mitótica aumentada e índice de Ki-67 elevado indicam alta probabilidade de neoplasia neuroendócrina. Cromogranina A e sinaptofisina favorecem o diagnóstico do bem diferenciado. Já a marcação positiva do BCL 10 em conjunto com a ausência de expressão da cromogranina A e da sinaptofisina mostram a precária diferenciação tumoral. A presença de marcação positiva para as expressões hormonais não define o tumor como funcionante. Conclusão: Houve aumento do diagnóstico de tumores neuroendócrinos pancreáticos com o uso de técnicas de imagem e a conscientização sobre a doença. A análise histopatológica com imunoistoquímica, especialmente quando há sintomas consumptivos, podem indicar o tipo do carcinoma e induzir ao mais adequado tratamento.
Introduction: Pancreatic neuroendocrine tumors are considered rare. They are classified into functioning and non-functioning. Objective: To define and classify pancreatic neuroendocrine tumors according to their histopathological and immunohistochemical evaluation, associated with diagnostic criteria. Method: This is a narrative review of publications found in PubMed, SciELO and Google Scholar. \Results: These tumors can be well or poorly differentiated and have distinct microscopic characteristics. Well-differentiated cells are small in shape, have uniform round or oval nuclei, finely granular cytoplasm indicating strong secretory capacity, and maintain the organoid structure. Presence of tumor necrosis, increased mitotic activity and high Ki-67 index indicate a high probability of neuroendocrine neoplasia. Chromogranin A and synaptophysin favor the diagnosis of well-differentiated. The positive staining of BCL 10 together with the absence of expression of chromogranin A and synaptophysin show poor tumor differentiation. The presence of positive staining for hormone expressions does not define the tumor as functioning. Conclusion: There was an increase in the diagnosis of pancreatic neuroendocrine tumors with the use of imaging techniques and awareness of the disease. Histopathological analysis with immunohistochemistry, especially when there are consuming symptoms, can indicate the type of carcinoma and lead to the most appropriate treatment.
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Humans , Pancreatic Neoplasms , Islets of LangerhansABSTRACT
Objective:To examine the possibility of the differentiation into islet-like cell clusters from the co-culture system of bone marrow mesenchymal stem cells (BMSCs) and islet cells.Methods:Rat BMSCs from the femur and tibia of Wistar rats were isolated and purified taken under aseptic conditions; the surface markers CD 44 and CD 90 expressions of BMSCs were detected by flow cytometry; and alizarin red staining and oil red O staining were used to identify the cells induced in the osteogenic direction and adipogenic direction, respectively. Rat islet cells from the pancreas of Wistar rats were isolated and purified; and dithiazone staining was performed for validation. The basal insulin level of the culture was detected by ELISA method. 5.6mmol/L (low glucose) and 25.0 mmol/L (high glucosa) glucose were added to the culture, respectively, and insulin release was detected by ELISA. 5-generation BMSCs and islet cells were collected and divided randomly into stem cell culture alone group (stem cell group), stem cell-islet co-culture group (co-culture group), and islet culture alone group (islet group). The morphological changes of BMSCs during co-culture were observed using an inverted phase contrast microscope; basal insulin secretion and insulin secretion stimulated by low and high glucose were tested by ELISA. Insulin protein expression in induced islet-like cell masses in co-culture group were detected by immunocytochemical staining. The ultrastructure of islet-like cells was observed by using transmission electron microscopy. Results:The positive rates of CD 44 and CD 90 were 99.48% and 99.50%, respectively; BMSCs were induced the formation of multiple calcium nodules outside the differentiation cells in the osteogenic direction, and many lipid droplets in the cytoplasm of differentiated cells in the adipogenic direction. Dithiazone staining showed that β cells in pancreatic islet were brown red and about 450 islets could be obtained per pancreas with a mean purity up to 80%. The insulin release in the low sugar group and the high sugar group were (7.105±1.551) mIU/ml and (20.231±1.592) mIU/ml, respectively, with a statistically significant difference ( P<0.05). It can be seen that local stem cells began to gather and grow upward into small clumps in the budding manner until finally forming a spherical islet-like cell cluster structure after 7 days of culture in the co-culture group. The basal insulin secretion in the stem cell group was <0.5 mIU/L. In the islet group, insulin secretion peaked on the 5th day and then gradually decreased to about 20% of the highest value on the 13th day. The insulin level of the co-culture group peaked on the 5th day, and the 13th day remained at about 40% of the peak level. There were statistically significant differences on basal insulin secretion on the 8th, 10th and 13th day between islet group and co-culture group (all P value >0.05). There was no statistically significant difference between the insulin release by islet in islet group under the stimulation of low and high sugar and that by islet-like cell cluster in co-culture group. There were a large number of brownish-yellow granules in the islet-like cell clusters after the co-culture for 14 days; and there were more secretory granules and coarse endoplasmic reticulum in the ultrastructure, showing more active protein secretion functions. Conclusions:The co-culture system of BMSCs and islet cells could induce BMSCs into differentiating into islet-like cell clusters, which can express insulin protein and had relatively mature function of insulin secretion.
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Chronic pancreatitis is a progressive chronic inflammatory disease of caused by gene and other environmental factors, and clinical manifestation includes recurrent abdominal pain and dysfunction of exocrine and endocrine. For the chronic pancreatitis therapy, surgical treatment mainly aims at the intractable pain which is unresponsive to medical and endoscopic treatment, as well as complications of chronic pancreatitis. Total pancreatectomy with islet autotransplantation (TPIAT) gradually becomes a major therapeutic option for chronic pancreatitis surgical treatment, because it relieves the abdominal pain, reduces the opioid dependent, improves the quality of life, and increases the opportunity of insulin independent. In the past few years, a range of researches have been focusing on islet isolation, surgical approach, curative effect and postoperative complication, improvement of islet function after operation. The purpose of this article is to summarize the progression of TPIAT related research in the recent years.
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Diabetes Mellitus (DM) is a metabolic syndrome characterized by hyperglycemia. Chronic complications affect a number of organs, including the lungs. Cissampelos sympodialis Eichl (Menispermaceae) is a plant used to treat respiratory diseases. The aim of this study was to evaluate the effect of Cissampelos sympodialis extract (CSE) in lungs of diabetic rats. We used 30 Wistar rats divided into three groups: control group (CG), diabetic group (DG) and diabetic Cissampelos sympodialis treatment group (DTG). Diabetes was induced by streptozotocin (40 mg/kg i.v.). The CSE (400 mg/kg, po) was administered daily, during four weeks, beginning one week after the onset of DM. The treatment with CSE was not able to reduce blood glucose levels after streptozotocin injection. However, it was able to decrease cholesterol and triglycerides and prevent damage on pancreatic islets morphology. Additionally, morphological alterations such as alveolar septa loss, inflammatory infiltrate and fibrosis were seen in lung tissue of rats with DM, and treatment with CSE apparently reversed these histopathological findings. Thus, CSE treatment reduced the lipid profile and restored the lung architecture of diabetic animals by a mechanism independent of glycemia and which might be associated with the reduction of the damage on the pancreatic islets.
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Cnidoscolus chayamansa is a native plant of the Mayan region, which is also cultivated in other places like northern Mexico, Tunisia and India. Many properties are attributed to Mayan Chaya, such as aid in the control of glycemia in diabetics. Thus this study aimed to evaluate the hypoglycemic effects of chaya aqueous extracts in a model of streptozotisin-induced diabetic Wistar rats. Chaya aqueous extracts were collected from plants cultivated in Quinta Roo (Mayan region) and Durango (northern Mexico), and in this study we compare their effect with metformin (as a control). Additionally, we compared the extracts mass profiles from both regions by high-resolution liquid chromatography coupled to a triple quadrupole tandem mass detector (HPLC-MS/MS QQQ). Finally, a study of the pancreatic tissue was carried out to evaluate the effects of the extracts on the Langerhans islets. Both extracts showed a good hypoglycemic effect after two weeks of treatment, and the Langerhans islets showed a partial recovery due to the effect of the treatment. Although the plants were cultivated at a distance of 2,350 km and under different weather, the compounds found in both did not show significant differences.
Subject(s)
Animals , Female , Rats , Plant Extracts/adverse effects , Streptozocin/administration & dosage , Euphorbiaceae/classification , Diabetes Mellitus/chemically induced , Hyperglycemia , Hypoglycemic Agents/adverse effects , Plants , Chromatography, High Pressure Liquid/methods , Islets of LangerhansABSTRACT
Longitudinal imaging of murine pancreas is technically challenging due to the mechanical softness of the tissue influenced by peristalsis. Here, we report a novel pancreatic imaging window for long-term stabilized cellular-level observation of the islets in the pancreas in vivo. By spatially separating the pancreas from the bowel movement and physiologic respiration with a metal plate integrated in the imaging window, we successfully tracked the pancreatic islets up to three weeks and visualized the dumbbell-shape transformation from the single islet. This window can be a useful tool for long-term cellular-level visualization of the microstructure in the pancreas.
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Animals , Mice , Intravital Microscopy , Islets of Langerhans , Pancreas , Peristalsis , RespirationABSTRACT
Background:Diabetes mellitus is the one of the most common endocrine diseases that is characterized by hyperglycemia, altered metabolism with an increased risk of much complications. Besides drugs classicallyused for the treatment of diabetes several species of plants have been described as having a hypoglycemic activity with decreased side effects. Aim of the Work:This work aimed to investigate the possible anti-diabetic effect of oral administration of pumpkin (Cucurbita maxima) fruit flesh and seeds powders on Streptozotocin induced diabetic rats via studying blood glucose levels, oxidative biomarkers as well as islets of Langerhans structure changes.Materials and Methods:60 adult albino rats of Sprague-Dawely strains (200±5 gm) were classified into five groups of ten animals each except diabetic control group was composed of twenty rats as follow Group I:healthy control;Group II:diabetic control ,Group III,IVandV: diabetic rats received 2g pumpkin fruit, seeds, fruit and seeds mixture powders respectively /kg body weight daily by oral intubation Results:The results of present study showed that pumpkin powders caused significant improvements (P≤0.05) in blood glucose, insulin levels and glycated hemoglobin percent compared to diabetic control group. Also pumpkin powders improved antioxidants activities andhealed Langerhans islets by increasing their number and size in comparison with diabetic control group. Conclusion:The present study showed that pumpkin powders may normalize the various biochemical and pancreatic tissues abnormalities resulted due to diabetes metabolic disorders and it is a source of potent anti-diabetic agent. The diabetic rats that were administered with the pumpkin fruit powder, exhibited the highest improvements.
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Forty aborted human fetuses (25 male, 15 female) of 12–40 weeks gestational age with no obvious congenital abnormality were obtained with the permission of Professor and Head, Department of Obstetrics and Gynaecology of our medical college and prior consent of the parents. The study was approved by the Ethical Committee of our college. These fetuses included spontaneous abortions and stillborns. The pancreas were dissected and paraffin blocks were prepared. The tissue was stained with hematoxylin and eosin. The development of the fetal pancreas at different gestational ages was noted and compared with previous studies.
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OBJECTIVE: Spinal cord injury (SCI) is a very serious health problem, usually caused by a trauma and accompanied by elevated levels of inflammation indicators. Stem cell-based therapy is promising some valuable strategies for its functional recovery. Nestin-positive progenitor and/or stem cells (SC) isolated from pancreatic islets (PI) show mesenchymal stem cell (MSC) characteristics. For this reason, we aimed to analyze the effects of rat pancreatic islet derived stem cell (rPI-SC) delivery on functional recovery, as well as the levels of inflammation factors following SCI. METHODS: rPI-SCs were isolated, cultured and their MSC characteristics were determined through flow cytometry and immunofluorescence analysis. The experimental rat population was divided into three groups : 1) laminectomy & trauma, 2) laminectomy & trauma & phosphate-buffered saline (PBS), and 3) laminectomy+trauma+SCs. Green fluorescent protein (GFP) labelled rPI-SCs were transplanted into the injured rat spinal cord. Their motilities were evaluated with Basso, Beattie and Bresnahan (BBB) Score. After 4-weeks, spinal cord sections were analyzed for GFP labeled SCs and stained for vimentin, S100β, brain derived neurotrophic factor (BDNF), 2’,3’-cyclic-nucleotide 3'-phosphodiesterase (CNPase), vascular endothelial growth factor (VEGF) and proinflammatory (interleukin [IL]-6, transforming growth factor [TGF]-β, macrophage inflammatory protein [MIP]-2, myeloperoxidase [MPO]) and anti-inflammatory (IL-1 receptor antagonis) factors. RESULTS: rPI-SCs were revealed to display MSC characteristics and express neural and glial cell markers including BDNF, glial fibrillary acidic protein (GFAP), fibronectin, microtubule associated protein-2a,b (MAP2a,b), β3-tubulin and nestin as well as antiinflammatory prostaglandin E2 receptor, EP3. The BBB scores showed significant motor recovery in group 3. GFP-labelled cells were localized on the injury site. In addition, decreased proinflammatory factor levels and increased intensity of anti-inflammatory factors were determined. CONCLUSION: Transplantation of PI-SCs might be an effective strategy to improve functional recovery following spinal cord trauma.
Subject(s)
Animals , Rats , Brain-Derived Neurotrophic Factor , Dinoprostone , Fibronectins , Flow Cytometry , Fluorescent Antibody Technique , Glial Fibrillary Acidic Protein , Inflammation , Islets of Langerhans , Laminectomy , Macrophages , Mesenchymal Stem Cells , Microtubules , Nestin , Neuroglia , Peroxidase , Regeneration , Spinal Cord Injuries , Spinal Cord , Stem Cell Transplantation , Stem Cells , Transforming Growth Factors , Vascular Endothelial Growth Factor A , Vimentin , Wounds and InjuriesABSTRACT
BACKGROUND: Protein arginine methyltransferase 1 (PRMT1) is a major enzyme responsible for the formation of methylarginine in mammalian cells. Recent studies have revealed that PRMT1 plays important roles in the development of various tissues. However, its role in pancreas development has not yet been elucidated. METHODS: Pancreatic progenitor cell-specific Prmt1 knock-out (Prmt1 PKO) mice were generated and characterized for their metabolic and histological phenotypes and their levels of Neurog3 gene expression and neurogenin 3 (NGN3) protein expression. Protein degradation assays were performed in mPAC cells. RESULTS: Prmt1 PKO mice showed growth retardation and a severely diabetic phenotype. The pancreatic size and β-cell mass were significantly reduced in Prmt1 PKO mice. Proliferation of progenitor cells during the secondary transition was decreased and endocrine cell differentiation was impaired. These defects in pancreas development could be attributed to the sustained expression of NGN3 in progenitor cells. Protein degradation assays in mPAC cells revealed that PRMT1 was required for the rapid degradation of NGN3. CONCLUSION: PRMT1 critically contributes to pancreas development by destabilizing the NGN3 protein.
Subject(s)
Animals , Mice , Diabetes Mellitus , Endocrine Cells , Gene Expression , Islets of Langerhans , Pancreas , Phenotype , Protein Stability , Protein-Arginine N-Methyltransferases , Proteolysis , Stem CellsABSTRACT
Zinc levels are high in pancreatic β-cells, and zinc is involved in the synthesis, processing and secretion of insulin in these cells. However, precisely how cellular zinc homeostasis is regulated in pancreatic β-cells is poorly understood. By screening the expression of 14 Slc39a metal importer family member genes, we found that the zinc transporter Slc39a5 is significantly down-regulated in pancreatic β-cells in diabetic db/db mice, obese ob/ob mice and high-fat diet-fed mice. Moreover, β-cell-specific Slc39a5 knockout mice have impaired insulin secretion. In addition, Slc39a5-deficient pancreatic islets have reduced glucose tolerance accompanied by reduced expression of Pgc-1α and its downstream target gene Glut2. The down-regulation of Glut2 in Slc39a5-deficient islets was rescued using agonists of Sirt1, Pgc-1α and Ppar-γ. At the mechanistic level, we found that Slc39a5-mediated zinc influx induces Glut2 expression via Sirt1-mediated Pgc-1α activation. These findings suggest that Slc39a5 may serve as a possible therapeutic target for diabetes-related conditions.
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OBJECTIVE: Spinal cord injury (SCI) is a very serious health problem, usually caused by a trauma and accompanied by elevated levels of inflammation indicators. Stem cell-based therapy is promising some valuable strategies for its functional recovery. Nestin-positive progenitor and/or stem cells (SC) isolated from pancreatic islets (PI) show mesenchymal stem cell (MSC) characteristics. For this reason, we aimed to analyze the effects of rat pancreatic islet derived stem cell (rPI-SC) delivery on functional recovery, as well as the levels of inflammation factors following SCI.METHODS: rPI-SCs were isolated, cultured and their MSC characteristics were determined through flow cytometry and immunofluorescence analysis. The experimental rat population was divided into three groups : 1) laminectomy & trauma, 2) laminectomy & trauma & phosphate-buffered saline (PBS), and 3) laminectomy+trauma+SCs. Green fluorescent protein (GFP) labelled rPI-SCs were transplanted into the injured rat spinal cord. Their motilities were evaluated with Basso, Beattie and Bresnahan (BBB) Score. After 4-weeks, spinal cord sections were analyzed for GFP labeled SCs and stained for vimentin, S100β, brain derived neurotrophic factor (BDNF), 2’,3’-cyclic-nucleotide 3'-phosphodiesterase (CNPase), vascular endothelial growth factor (VEGF) and proinflammatory (interleukin [IL]-6, transforming growth factor [TGF]-β, macrophage inflammatory protein [MIP]-2, myeloperoxidase [MPO]) and anti-inflammatory (IL-1 receptor antagonis) factors.RESULTS: rPI-SCs were revealed to display MSC characteristics and express neural and glial cell markers including BDNF, glial fibrillary acidic protein (GFAP), fibronectin, microtubule associated protein-2a,b (MAP2a,b), β3-tubulin and nestin as well as antiinflammatory prostaglandin E2 receptor, EP3. The BBB scores showed significant motor recovery in group 3. GFP-labelled cells were localized on the injury site. In addition, decreased proinflammatory factor levels and increased intensity of anti-inflammatory factors were determined.CONCLUSION: Transplantation of PI-SCs might be an effective strategy to improve functional recovery following spinal cord trauma.
Subject(s)
Animals , Rats , Brain-Derived Neurotrophic Factor , Dinoprostone , Fibronectins , Flow Cytometry , Fluorescent Antibody Technique , Glial Fibrillary Acidic Protein , Inflammation , Islets of Langerhans , Laminectomy , Macrophages , Mesenchymal Stem Cells , Microtubules , Nestin , Neuroglia , Peroxidase , Regeneration , Spinal Cord Injuries , Spinal Cord , Stem Cell Transplantation , Stem Cells , Transforming Growth Factors , Vascular Endothelial Growth Factor A , Vimentin , Wounds and InjuriesABSTRACT
BACKGROUND: Bone marrow mesenchymal stem cells have been induced into islet-like cell mass in vitro. However, little researches reported on the morphological changes of cells, the types of endocrine cells in the islet-like cell mass and their relationships. OBJECTIVE: To investigate the morphological changes of cells in the differentiation of bone marrow mesenchymal stem cells into islet-like structure and to explore the composition and distribution of endocrine cells. METHODS: Passage 3 bone marrow mesenchymal stem cells growing well were cultured and expanded until the cell colonies occupies 80% of the bottom of the culture bottle, and the pancreatic tissue lysate was added for continuous induction. Dithizone staining was used to screen the islet-like cell mass directly differentiated from bone marrow mesenchymal stem cells. The types and distribution of endocrine cells were identified by Mallory staining. Expressions of insulin, C-peptide, glucagon and somatostatin protein were detected by immunofluorescence cytochemical staining. RESULTS AND CONCLUSION: (1) Dithizone staining showed that the number of positive cells was increased over the induction time. (2) Mallory staining showed the red α-like cells were located in the periphery of the islet-like cell mass, the yellow β-like cells located in the center and periphery, and the light blue fibroblasts were distributed around the cell mass. (3) Immunofluorescence staining showed insulin, C-peptide, glucagon and somatostatin positive cells in the islet-like cell mass. To conclude, under certain microenvironment, bone marrow mesenchymal stem cells can differentiate into islet-like structures which containing α, β, δ-like cells, and are surrounded by fibroblast-like cells.
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ABSTRACT Objective: To investigate the anti-hyperglycemic effects of Plathymenia reticulata hydroalcoholic extract and related changes in body weight, lipid profile and the pancreas. Methods: Diabetes was induced in 75 adult male Wistar rats via oral gavage of 65mg/Kg of streptozotocin. Rats were allocated to one of 8 groups, as follows: diabetic and control rats treated with water, diabetic and control rats treated with 100mg/kg or 200mg/kg of plant extract, and diabetic and control rats treated with glyburide. Treatment consisted of oral gavage for 30 days. Blood glucose levels and body weight were measured weekly. Animals were sacrificed and lipid profile and pancreatic tissue samples analyzed. Statistical analysis consisted of ANOVA, post-hoc Tukey-Kramer, paired Student's t and χ2 tests; the level of significance was set at 5%. Results: Extract gavage at 100mg/kg led to a decrease in blood glucose levels in diabetic rats in the second, third (198.71±65.27 versus 428.00±15.25) and fourth weeks (253.29±47.37 versus 443.22±42.72), body weight loss (13.22±5.70 versus 109.60±9.95) and lower cholesterol levels (58.75±3.13 versus 80.11±4.01) in control rats. Extract gavage at 200mg/Kg led to a decrease in glucose levels on the fourth week in diabetic rats, body weight loss in the second, third and fourth weeks in control rats, and lower cholesterol levels in diabetic and control rats. Islet hyperplasia (p=0.005) and pancreatic duct dilation (p=0.047) were observed in diabetic and control rats. Conclusion: Plathymenia extract reduced blood glucose levels in diabetic rats, and body weight in control rats, and promoted pancreatic islet hyperplasia in diabetic and control rats.
RESUMO Objetivo: Avaliar o efeito anti-hiperglicêmico do extrato hidroalcoólico de Plathymenia reticulata, alterações no peso, lipídeos e efeito sobre o pâncreas. Métodos: O diabetes foi induzido pela administração de estreptozotocina 65mg/kg, em 75 ratos Wistar adultos machos, divididos em 8 grupos diferentes: ratos diabéticos e controle + água, ratos diabéticos e controle + 100mg/kg ou 200mg/kg de extrato, ratos diabéticos e controle + gliburida. O tratamento foi realizado por gavagem (oral) por 30 dias. Níveis de glicose e peso foram verificados semanalmente. Os animais foram sacrificados, e amostras de lipídeos e do pâncreas foram analisadas. A análise estatística incluiu ANOVA, post-hoc Tukey-Kramer, teste t de Student pareado e teste do χ2, com nível de significância de 5%. Resultados: O extrato 100mg/kg promoveu redução nos níveis de glicose sanguínea em ratos diabéticos na segunda, terceira (198,71±65,27 versus 428,00±15,25) e quarta semanas (253,29±47,37 versus 443,22±42,72), perda de peso (13,22±5,70 versus 109,60±9,95) e diminuição do colesterol (58,75±3,13 versus 80,11±4,01) em ratos controle. Com extrato de 200mg/kg, houve redução dos níveis de glicose na quarta semana, nos ratos diabéticos; de peso na segunda, terceira e quarta semanas, nos ratos controle; e de colesterol nos animais diabéticos e controle. Ocorreram hiperplasia de ilhotas (p=0,005) e dilatação dos ductos pancreáticos (p=0,047) em ratos diabéticos e controles. Conclusão: O extrato de Plathymenia reduziu os níveis de glicose em ratos diabéticos e de peso em ratos controle, além de ter promovido hiperplasia de ilhotas pancreáticas em diabéticos e controles.
Subject(s)
Animals , Male , Rats , Plant Extracts/pharmacology , Diabetes Mellitus, Experimental/drug therapy , Hypoglycemic Agents/pharmacology , Fabaceae , Blood Glucose/analysis , Body Weight/drug effects , Cholesterol , Rats, Wistar , Streptozocin , Plant Leaves , Diabetes Mellitus, Experimental/chemically induced , Disease Models, Animal , Hyperplasia/pathology , PhytotherapyABSTRACT
Objective This study was conducted to establish a stable and highly efficient method for isolation and purification of pancreatic islets from NOD mice and to evaluate their characteristics in vitro and in vivo. Methods The is-lets were isolated from mouse pancreas using modified collagenase digestion and Ficoll density gradient centrifugation. The endocrine secretory function was assessed by insulin secretion in either low or high dose glucose stimulation. To evaluate the function of the graft,body weight and blood glucose were monitored,and IVGTT was performed. In addition,to assess sur-vival of the implanted islets,Pathology using HE staining and insulin immunostaining of the graft were performed. Results The average islet yield was 116 ± 12 islets/pancreas and purity was higher than 90%. Compared with islets from Kunming mice,the islets isolated from NOD mice were poorly responsive to glucose challenge. Blood glucose levels and body weight changes of the islet-transplanted diabetic mice were significantly improved compared with the sham-operated mice. In addi-tion,blood glucose levels in vivo after an IVGTT also significantly improved. However,these improvements were only main-tained for 2 weeks. Furthermore,HE staining and immunostaining assays demonstrated that there were insulin-positive cell clusters and lymphocyte infiltration in the graft-bearing kidney. Conclusions A large number of quality islets can be isola-ted and purified from NOD mice by using the modified mouse islet isolation method, which can be used to develop thera-peutic strategies to protect transplanted islets from rejection and autoimmune attack.
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Over the past three decades, human pancreatic islet isolation and transplantation techniques have developed as a routine clinical procedure for selected patients with type 1 diabetes mellitus. However, due to the donor shortage and required chronic systemic immunosuppression, the widespread application of islet transplantation is limited. To overcome these limitations, providing a physical barrier to transplanted islet cells with encapsulating biomaterial has emerged as a promising approach to enhance engraftment and promote islet survival post-transplantation. Alginate has been considered to be a reliable biomaterial, as it enhances islet survival and does not hamper hormone secretion. Alginate-catechol (Al-CA) hydrogel was reported to provide high mechanical strength and chemical stability without deformation over a wide range of pH values. In this study, we, demonstrated, for the first time in the literature, that encapsulation of murine pancreatic islet cells with Al-CA hydrogel does not induce cytotoxicity ex vivo for an extended period; however, it does markedly abate glucose-stimulated insulin secretion. Catechol should not be considered as a constituent for alginate gelation for encapsulating islet cells in the application of islet transplantation.
Subject(s)
Humans , Architectural Accessibility , Diabetes Mellitus, Type 1 , Hydrogels , Hydrogen-Ion Concentration , Immunosuppression Therapy , Insulin , Islets of Langerhans Transplantation , Islets of Langerhans , Temefos , Tissue DonorsABSTRACT
Among the innovations for the treatment of type 1 diabetes, islet transplantation is a less invasive method of treatment, although it is still in development. One of the greatest barriers to this technique is the low number of pancreas donors and the low number of pancreases that are available for transplantation. Rodent models have been chosen in most studies of islet rejection and type 1 diabetes prevention to evaluate the quality and function of isolated human islets and to identify alternative solutions to the problem of islet scarcity. The purpose of this study is to conduct a review of islet xenotransplantation experiments from humans to rodents, to organize and analyze the parameters of these experiments, to describe trends in experimental modeling and to assess the viability of this procedure. In this study, we reviewed recently published research regarding islet xenotransplantation from humans to rodents, and we summarized the findings and organized the relevant data. The included studies were recent reports that involved xenotransplantation using human islets in a rodent model. We excluded the studies that related to isotransplantation, autotransplantation and allotransplantation. A total of 34 studies that related to xenotransplantation were selected for review based on their relevance and current data. Advances in the use of different graft sites may overcome autoimmunity and rejection after transplantation, which may solve the problem of the scarcity of islet donors in patients with type 1 diabetes.
Subject(s)
Humans , Animals , Islets of Langerhans Transplantation/methods , Latent Autoimmune Diabetes in Adults/surgery , Models, Animal , Transplantation, Heterologous/methods , Graft Survival , Islets of Langerhans Transplantation/statistics & numerical data , Islets of Langerhans Transplantation/trends , Mice, Inbred C57BL/surgery , Rodentia , Transplantation, Heterologous/statistics & numerical data , Transplantation, Heterologous/trendsABSTRACT
Several studies indicated that pancreatic ß-cell death occurs in both type 1 and type 2 diabetes. This experimental study was designed to determine the effect of gestational diabetes on the ß-cells in 16-week-old rat offspring. By this aim, adult Wistar rats aged 10-12 weeks were randomly allocated in control and diabetic groups. The diabetic group received 40 mg/kg/body weight of streptozotocin (STZ) on day zero of gestation. After delivery, diabetic offspring of GDM mothers and controls at the age of 16 weeks were sacrificed and pancreases harvested and fixed. The number of ß-cells and were counted by Gomori's method staining. Also, apoptosis in pancreas tissue of diabetic and control offspring was detected by TUNEL assay. Results showed a significant reduction in ß-cell number in offspring of GDM (p<0.05). TUNEL assay showed that the number of apoptotic cells increased in GDM compared to controls (P<0.05). This study revealed that gestational diabetes induces pancreatic beta-cells apoptosis in 16-week-old rat offspring.
Varios estudios indican que la muerte de las células ß del páncreas se produce tanto en la diabetes Tipo 1 como en la Tipo 2. Este estudio experimental fue diseñado para determinar el efecto de la diabetes gestacional en las células ß del páncreas en crías de ratas de 16 semanas. Para ello, ratas Wistar adultas de entre 10-12 semanas fueron asignadas al azar en dos grupos: control y diabetes. El grupo diabetes recibió 40 mg / kg / peso corporal de estreptozotocina (STZ) en el día cero de la gestación. Después del parto, a las 16 semanas, las crías de las madres diabéticas y controles de madres con diabetes gestacional (MDG), fueron sacrificadas para la extracción del páncreas, el cual posteriormente fue fijado. Se contó el número de células ß del páncreas mediante tinción con el método de Gomori. Además, se detectó apoptosis en el tejido del páncreas de la descendencia diabética y el grupo control mediante un ensayo TUNEL. Los resultados mostraron una reducción significativa en el número de células b en la descendencia de MDG (p <0,05). El ensayo TUNEL mostró que el número de células apoptóticas aumentó en MDG en comparación con los controles (P <0,05). Este estudio reveló que la diabetes gestacional induce apoptosis de células ß en el páncreas de crías de ratas de 16 semanas.