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Viral diabetes mellitus in man and experimental animals.

Accumulating evidence strongly suggests that viruses may play an etiologic role in some cases of diabetes mellitus. The importance of environmental factors in the pathogenesis of the disease is suggested by genetic and epidemiological observations. Group B Coxsackie viruses and mumps virus have been implicated, and the evidence suggests that several other agents also could play a role in the disease. In experimental animals, a picornavirus similar to the Coxsackie viruses exhibits specific tropism for the beta cells of the islets of Langerhans, causing a disease in mice that is similar to juve…

Cell features in pancreas of prediabetic and diabetic rabbits after Wirsung duct ligation. Histochemical and histoenzymatic studies.

Kinetic studies of the histochemical and histoenzymatic behavior of rabbit pancreatic parenchymas were performed 5, 30 and 90 days after Wirsung duct ligation. In control pancreas, some enzyme activities (EA) were more prominent in Langerhans islets [glucose-6-phosphatase, glucose-6-phosphate dehydrogenase (DH), isocitrate DH, glycerol-3-phosphate DH, NADPH DH], others were strongly marked in acini and ducts (alkaline phosphatase, beta-glucuronidase, acid esterase aryl-sulfatase). Histochemical and enzyme abnormalities observed in experimental rabbits reflect the post-ligation degenerative and

Beyond the loss of beta cells: a quantitative analysis of islet architecture in adults with and without type 1 diabetes.

AIMS/HYPOTHESIS: The organisation and cellular architecture of islets of Langerhans are critical to the physiological regulation of hormone secretion but it is debated whether human islets adhere to the characteristic mantle-core (M-C) structure seen in rodents. It is also unclear whether inherent architectural changes contribute to islet dysfunction in type 1 diabetes, aside from the loss of beta cells. Therefore, we have exploited advances in immunostaining, spatial biology and machine learning to undertake a detailed, systematic analysis of adult human islet architecture in health and type …

Heat shock response to exercise in pancreatic islets of obese mice.

Chronic obesity imposes an organismal state of low-grade inflammation because the physiological resolution of inflammation is progressively … jeopardized by obesity-related dysfunctions is the endocrine pancreas, particularly β-cells of the islets of Langerhans. Because exercise is a powerful inducer of HSR and predicted to alleviate negative health outcomes of obesity, we sought whether obesity influence HSP70 expression in pancreatic islets and other metabolic tissues (adipose tissue and skeletal muscle) …

BRICHOS domain of Bri2 inhibits islet amyloid polypeptide (IAPP) fibril formation and toxicity in human beta cells.

Aggregation of islet amyloid polypeptide (IAPP) into amyloid fibrils in islets of Langerhans is associated with type 2 diabetes, and formation of toxic IAPP species is believed to contribute to the loss of insulin-producing beta cells. The BRICHOS domain of integral membrane protein 2B (Bri2), a transmembrane protein expressed in several peripheral tissues and in the brain, has recently been shown to prevent fibril formation and toxicity of Aβ42, an amyloid-forming peptide in Alzheimer disease. In this study, we demonstrate expression of Bri2 in human islets and in the human beta-cell line End…

Координирующее выражение интерлейкин-2 не нарушает нечувствительность к "само" (вирусному) антигену, выраженному в бета-элементах, а способствует развитию аутоиммунной болезни (диабета) после инициирования антисамоиммунной реакции.

Участие IL-2 в инсулиновом диабете (тип 1) (IDDM) было проанализировано в трансгенных (tg) мышах, выражающих нуклеопротеин (NP) вируса лимфоцита хориоменита и IL-2, находящихся под контролем крысиного пропагандиста инсулина, в бета-клетках островов Лангерхан. Введение и выражение вирусного (само) гена или одного только гена IL-2 не привело к IDDM. Инфильтрация главным образом CD4 и B лимфоцитов и увеличение содержания молекул MHC классов I и II имели место в азбуках, где был выражен IL-2. Напротив, в тг, выражающих вирусный белок, не было отмечено ни проникновения в клетки, ни выражения гликпр

Совпадение в аннотации оригинала
The participation of IL-2 in insulin-dependent (type 1) diabetes (IDDM) was analyzed in transgenic (tg) mice expressing the nucleoprotein (NP) of lymphocytic choriomeningitis virus and IL-2 under control of the rat insulin promoter focally in beta cells of the islets of Langerhans. Insertion and expression of the viral (self) gene or of the IL-2 gene alone d…

FGF-23 protects cell function and viability in murine pancreatic islets challenged by glucolipotoxicity.

The fibroblast growth factor FGF-23 is a member of the FGF-15/19 subfamily with hormonal functions. Besides its well-known role for bone min … st that FGF-23 can activate compensatory mechanisms to maintain beta-cell function and integrity of islets of Langerhans during excessive glucose and lipid supply.

Donor age significantly influences the Raman spectroscopic biomolecular fingerprint of human pancreatic extracellular matrix proteins following collagenase-based digestion.

Despite the enormous advances in the field of clinical pancreatic islet transplantation over the past two decades, the human islet isolation … nimally invasive treatment, which can reverse Type 1 Diabetes Mellitus (T1DM) in selected patients. Islets of Langerhans are extracted (isolated) from the exocrine tissue of human donor pancreases using neutral protease (NP) and collagenase-based enzymes, which digest the extracellular matrix (ECM) scaffold surrounding human islets. This process remains highly variabl …

Fibroblast growth factor 7 releasing particles enhance islet engraftment and improve metabolic control following islet transplantation in mice with diabetes.

Transplantation of islets in type 1 diabetes (T1D) is limited by poor islet engraftment into the liver, with two to three donor pancreases required per recipient. We aimed to condition the liver to enhance islet engraftment to improve long-term graft function. Diabetic mice received a non-curative islet transplant (n = 400 islets) via the hepatic portal vein (HPV) with fibroblast growth factor 7-loaded galactosylated poly(DL-lactide-co-glycolic acid) (FGF7-GAL-PLGA) particles; 26-µm diameter particles specifically targeted the liver, promoting hepatocyte proliferation in short-term experiments

MRI monitoring of transplanted neonatal porcine islets labeled with polyvinylpyrrolidone-coated superparamagnetic iron oxide nanoparticles in a mouse model.

Islet transplantation is a potential treatment option for certain patients with type 1 diabetes; however, it still faces barriers to widespread use, including the lack of tools to monitor islet grafts post-transplantation. This study investigates whether labeling neonatal porcine islets (NPI) with polyvinylpyrrolidone-coated superparamagnetic iron oxide nanoparticles (PVP-SPIO) affects their function, and whether this nanoparticle can be utilized to monitor NPI xenografts with magnetic resonance imaging (MRI) in a mouse model. In vitro, PVP-SPIO-labeled NPI in an agarose gel was visualized cle

Heterogeneity and neurovascular integration of intraportally transplanted islets revealed by 3-D mouse liver histology.

Intraportal islet transplantation has been clinically applied for treatment of unstable type 1 diabetes. However, in the liver, systematic assessment of the dispersed islet grafts and the graft-hepatic integration remains difficult, even in animal models. This is due to the lack of global and in-depth analyses of the transplanted islets and their microenvironment. Here, we apply three-dimensional (3-D) mouse liver histology to investigate the islet graft microstructure, vasculature, and innervation. Streptozotocin-induced diabetic mice were used in syngeneic intraportal islet transplantation t

A Method for Performing Islet Transplantation Using Tissue-Engineered Sheets of Islets and Mesenchymal Stem Cells.

Mesenchymal stem cells (MSCs) are known to have a protective effect on islet cells. Cell sheets developed using tissue engineering help maintain the function of the cells themselves. This study describes a tissue engineering approach using islets with MSC sheets to improve the therapeutic effect of islet transplantation. MSCs were obtained from Fischer 344 rats and engineered into cell sheets using temperature-responsive culture dishes. The islets obtained from Fischer 344 rats were seeded onto MSC sheets, and the islets with MSC sheets were harvested by low-temperature treatment after cocultu

Endovascular method for transplantation of insulin-producing cells to the pancreas parenchyma in swine.

Insulin-producing cells are transplanted by portal vein injection as an alternative to pancreas transplantation in both clinical and preclinical trials. Two of the main limitations of portal vein transplantation are the prompt activation of the innate immunity and concomitant loss of islets and a small but significant risk of portal vein thrombosis. Furthermore, to mimic physiological release, the insulin-producing cells should instead be located in the pancreas. The trans-vessel wall approach is an endovascular method for penetrating the vessel wall from the inside. In essence, a working chan

Cryopreservation of chick islets.

The avian endocrine pancreas shares some similarities with those of mammals. Previously we have reported a technique of isolation of B islets from chick pancreas and also demonstrated their possible use for hypoglycemic drug screening as efficiently as mammalian islets. Here we describe a novel cryopreservative medium for the cryopreservation of chick islets. Isolated chick islets were suspended in a cryo medium consisting of Dulbecco's modified Minimum Essential Medium: Ham's F12 (1:1), Fetal Bovine Serum (20%), Dimethylsulfoxide (10%) with different concentrations (50 microg/ml to 500 microg

Applications of organ precursor cell therapy: can lessons from embryonic kidney transplantation be applied to the endocrine pancreas?

PURPOSE OF REVIEW: The purpose of this review is to provide an update relating to a novel approach to endocrine pancreas replacement therapy … reatic anlagen implanted into a host peritoneum develop into a novel organ consisting of functional islets of Langerhans surrounded by stroma. The transplantation of developing pancreas could represent a novel 'cellular' treatment for diabetes mellitus, a major cause of end-stage renal disease.

The use of non-heart-beating donors for isolated pancreatic islet transplantation.

Recent improvements in isolated islet transplantation indicate that this therapy may ultimately prove applicable to patients with type I diabetes. An obstacle preventing widespread application of islet transplantation is an insufficient supply of cadaveric pancreata. Non-heart-beating donors (NHBDs) are generally not deemed suitable for whole-organ pancreas donation and could provide a significant source of pancreata for islet transplantation. Isolated pancreatic islets prepared from 10 NHBDs were compared with those procured from 10 brain-dead donors (BDDs). The success of the isolation for t

Xenotransplantation of porcine pancreatic endocrine cells to total pancreatectomized dogs.

Xenotransplantation of porcine pancreatic endocrine (PE) cells in a diffusion chamber, a bioartificial endocrine pancreas (Bio-AEP), was conducted to total pancreatectomized dogs. Six pancreatectomized dogs were divided into two groups of 3 dogs each. In three dogs of the control group, exogenous insulin was administered twice a day for 30 weeks to maintain fasting blood glucose (FBG) levels within the normal range. The remaining three dogs were implanted with Bio-AEPs (implantation group), in addition to daily insulin administration. In the implantation group, Bio-AEPs containing 1.3 to 1.8 x

Prior streptozotocin treatment does not inhibit pancreas regeneration after 90% pancreatectomy in rats.

The effects of residual beta-cell mass and glycemia on regeneration of endocrine pancreas after 90% pancreatectomy were investigated. Streptozotocin or buffer alone was injected into 4-wk-old male Lewis rats (day 0). On day 7, varying numbers of syngeneic islets were transplanted under the kidney capsule to achieve varying degrees of glucose normalization. On day 14, a 90% pancreatectomy or sham pancreatectomy was performed. On day 19, rats were killed and the pancreas was fixed for quantitative morphometric determination of beta-cell mass. Focal areas of regenerating pancreas were observed in

Glutamic acid decarboxylase antibodies are more frequent than islet cell antibodies in islet transplanted IDDM patients and persist or occur despite immunosuppression.

Pancreatic islet grafts transplanted into patients with autoimmune diabetes are potentially threatened by two immune responses, allograft rejection and the recurrence of autoimmune insulitis. In the present study we investigated the humoral autoimmune response directed to islet autoantigens by studying islet cell antibodies and glutamic acid decarboxylase (GAD 65) antibodies in twenty-one insulin-dependent diabetes-mellitus (IDDM) patients undergoing intraportal islet allotransplantation. Islet transplantation was performed according to the following recipient categories: Islet after kidney tr