胎鼠胰腺干细胞与胰岛联合移植保护胰岛

背景：胰腺干细胞可在体外维持胰岛的结构,减少胰岛细胞坏死及凋亡,延长胰岛的体外存活时间,保护胰岛的活性。 目的：探索胎鼠胰腺干细胞与胰岛共移植体内保护移植胰岛,提高胰岛移植疗效的可行性。 方法：将成年大鼠35只随机等分为联合移植组、单独胰岛移植组、单纯胰腺干细胞移植组、模型组及对照组,前4组均腹腔注射链脲佐菌素-柠檬酸盐缓冲液建立糖尿病模型。联合移植组、单独胰岛移植组、单纯胰腺干细胞大鼠分别在左侧肾包膜下移植分离纯化孕16 d SD大鼠胎鼠胰腺干细胞和/或成年SD大鼠胰岛。 结果与结论：联合移植组大鼠移植后5 d内血糖可降至正常,血浆胰岛素达到正常水平,胰岛存活时间(18.2±2.4) d;单独移植组大鼠血糖可于移植后1周内降至正常,胰岛存活时间(14.4±2.1) d;两组胰岛存活时间比较差异有显著性意义(P < 0.05)。而其他组糖尿病大鼠血糖均未能降至正常范围。说明胎鼠胰腺干细胞与胰岛共移植可延长胰岛体内存活时间,保护胰岛功能,提高移植疗效。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

Viral antigen in endocrine cells of the pancreatic islets and adrenal cortex of Pekin ducks infected with duck hepatitis B virus

Endocrine cells in the pancreas and adrenal glands of duck hepatitis B virus-infected ducks were examined for the presence of viral antigen. Analysis of pancreas tissue was based on double immunofluorescence assays in which anti-duck hepatitis B virus serum was used to detect viral antigen, and anti-glucagon and anti-insulin serum were used, respectively, to identify endocrine alpha and beta cells. Assays of pancreas from infected ducks ranging in age from 3 to 20 weeks indicated that subpopulations of both alpha and beta cells expressed viral antigen. A higher percentage of viral antigen-positive cells was observed in alpha-islets than in beta-islets. As assayed by immunofluorescence and immunoperoxidase staining with anti-viral serum, small clusters of viral antigen-positive cells were detected in the adrenal glands of young infected ducks. These cells were identified as cortical cells on the basis of histologic criteria.     

The effect of adrenocortical hormones on water permeability of the collecting duct of the rat

The diffusional water permeability of collectings ducts in papillae isolated from adrenalectomised rats was not different from that in papillae from normal animals. The increases in diffusional water permeability to concentrations of antidiuretic hormone which produced submaximal and maximal response were similar in papillae from normal and adrenalectomised rats.The amount of cyclic AMP in papillae from adrenalectomised rats was significantly higher than that in papillae from normal rats. The increment in cyclic AMP level, after incubation in medium containing antidiuretic hormone, was significantly smaller in papillae from adrenalectomised rats. The injection of adrenalectomised rats with dexamethasone significantly enhanced the increment in cyclic AMP levels observed after incubation in medium containing antidiuretic hormone. The injection of adrenalectomised rats with aldosterone had no effect. The addition of aldosterone to the incubation bath however significantly enhanced the increment of cyclic AMP levels produced by antidiuretic hormone. When dexamethasone was added to the incubation bath no change in basal or antidiuretic hormone stimulated levels of cyclic AMP was detectable.The impaired capacity to excrete water after adrenalectomy is therefore not due to an increased reabsorption of water in the collecting system in the presence or in the absence of antidiuretic hormone. The physiological significance of the changes in the antidiuretic hormone cyclic AMP metabolic cycle is yet to be determined.Supported by N.H. & M.R.C. and the Australian Kidney Foundation     

Peptidergic hormones and neuropeptides, and aminergic neurotransmitters of the pancreatic islets of the Houbara bustard (Chlamydotis undulata)

Immunoreactivity to insulin (Ins), somatostatin (Som), glucagon (Glu) and pancreatic polypeptide (PP) was found in 70%, 22%, 15% and 11% respectively of Houbara pancreatic endocrine islet cells. Whilst Ins occurred centrally and SOM was observed both in peripherally and centrally located islets, the other hormones were localised in peripheral islet cells; Som was also observed in neuronal cell bodies and nerve fibres. In addition, the islet cells contained substance P (SP) (65%) in the centre and vasoactive intestinal polypeptide (VIP) (2%) at the periphery. Immunoreactivity to choline acetyltransferase (ChAT), VIP and galanin (Gal) occurred in the walls of blood vessels located mainly at the periphery of islets. Occasionally, VIP and Gal immunoreactive varicose nerve terminals and ChAT immunoreactive cell bodies were also observed in the centre of islets. SP neuronal cell bodies were not observed but prominent SP immunoreactive varicose terminals were discernible in capillary walls within the islets. Neuropeptide Y (NPY) immunoreactive neurons were detected in neuronal cell bodies located mainly peripherally. Neuronal nitric oxide synthase (nNOS) immunoreactivity occurred in neuronal cell bodies and nerve fibres mainly at the periphery and also in centrally located islet endocrine cells. Immunoreactivity to tyrosine hydroxylase (TH) was similar in distribution to that of ChAT. In comparison with other avian species, the islets of the dorsal pancreatic lobe of the bustard contain all the peptidergic hormones normally present in the islets of other avian species, but are not segregated into dark A and light B cells. Many of the insulin containing cells also contained SP. The islets also contained several neuropeptides which are probably involved in their regulation.     

Role of the incretory function of the pancreatic islets in the mechanisms of development of hypothalamic obesity

Administration of alloxan, which injures the cells and depresses insulin secretion, to animals with experimental hypothalamic obesity prevented any further increase in body weight despite an excessive food intake by the animals. It is concluded that the most important mechanism of development of obesity following injury to the ventromedial hypothalamic nuclei is the hypersecretion of insulin caused by such injury.Department of Pathological Physiology, Karaganda Medical Institute. Department of Medical Radiology, Central Postgraduate Medical Institute, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. D. Gorizontov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 10, pp. 1185–1187, October, 1976.     

Effect of diabetogenic agents on zinc and calcium concentrations in rabbit pancreatic islet cells

Research Institute of Pharmacology, Tomsk Scientific Center, Academy of Medical Sciences of the USSR, Tomsk. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 2, pp. 135–137, February, 1991.     

Studies on co-localization of 7B2 and pancreatic hormones in normal and tumoural islet cells

Summary The distribution of protein 7B2, a protein with structural characteristics of GTP-binding proteins, has been studied in normal pancreatic islets and in a series of 70 pancreatic endocrine tumours with emphasis on the co-localization of 7B2 and the different pancreatic hormones. Although all cell types of normal islets were found to store 7B2, variations from intense expression to absence of reaction were seen within each cell type. In particular, B cells showed intense immunostaining for 7B2 in small compact islets and weak or no staining in larger islets with lobular arrangement. Pancreatic polypeptide (PP) cells expressed 7B2 intensely in the PP-rich area of ventral embryological origin, but were mostly non-reactive in the PP-poor area. The A cells, located along intralobular blood vessels, were more frequently immunoreactive for 7B2 than those at the periphery of the islets. Immuno-electron microscopy revealed a preferential localization of 7B2 in secretory granules of islet cells, with more intense localization in the peripheral halo of alpha granules. Benign islet cell tumours more frequently expressed 7B2 than their malignant counterparts. Although often expressed in a lower number of tumour cells than the tumour-specific hormone, 7B2 was usually co-localized with the latter. In contrast, no relationship was found with the localization of proinsulin. It is concluded that 7B2 is a non-permanent component of the cell granule compartment, probably involved in events related to exocytosis and without relationship to intracellular prohormone processing.     

Effect of a new synthetic serum replacement on insulin and somatostatin secretion from isolated rat pancreatic islets in long-term culture

Summary Serum contains insulin degrading components. We have evaluated the insulin and somatostatin secretion from isolated rat pancreatic islets during a 2-wk culture period using three different serum-containing media, and one serum-free medium with a synthetic serum replacement. Islets incubated in serum-free medium elicited significantly higher daily insulin and somatostatin secretions than islets incubated in the serum-containing media. After a 2-wk culture period, islets from the serum-free medium secreted significantly more insulin and somatostatin than islets cultured in other media when stimulated with 25 mmol/liter glucose together with 15 mmol/liter theophylline. We conclude that the serum-free medium is superior for long-term culture of rat pancreatic islets.     

Dual origin,development, and fate of bovine pancreatic islets

Endocrine cells are evident at an early stage in bovine pancreatic development when the pancreas still consists of primitive epithelial cords. At this stage, the endocrine cells are interspersed between the precursor cells destined to form the ductulo‐acinar trees of later exocrine lobules. We here demonstrate that, in bovine fetuses of crown rump length ≥ 11 cm, the endocrine cells become increasingly segregated from the developing exocrine pancreas by assembly into two units that differ in histogenesis, architecture, and fate. Small numbers of ‘perilobular giant islets’ are distinguishable from larger numbers of ‘intralobular small islets’. The two types of islets arise in parallel from the ends of the ductal tree. Aside from differences in number, location, and size, the giant and small islets differ in cellular composition (predominantly insulin‐synthesising cells vs. mixtures of endocrine cells), morphology (epithelial trabeculae with gyriform and rosette‐like appearance vs. compact circular arrangements of endocrine cells), and in their relationships to intrapancreatic ganglia and nerves. A further difference becomes apparent during the antenatal period; while the ‘interlobular small islets’ persist in the pancreata of calves and adult cattle, the perilobular giant islets are subject to regression, characterised by involution of the parenchyma, extensive haemorrhage, leukocyte infiltration (myeloid and T‐cells) and progressive fibrotic replacement. In conclusion, epithelial precursor cells of the ductolo‐acinar tree may give rise to populations of pancreatic islets with different histomorphology, cellular composition and fates. This should be taken into account when using these cells for the generation of pancreatic islets for transplantation therapy.     

Effect of the diabetogenic agent dithisone on zinc concentration in pancreatic islets of animals of different species

Research Institute of Pharmacology, Tomsk Scientific Center, Academy of Medical Sciences of the USSR. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 1, pp. 53–55, January, 1992.     

Potassium and chloride fluxes are involved in volume regulation in mouse pancreatic islet cells

Potassium and chloride transport were measured in β-cell-rich islets from ob/ob-mice using ³⁶Cl^-86Rb⁺ (K⁺-analogue). Reduction of the osmolarity from the normal 317 mosm l^-1 to 180 mosm l^-1 reduced the apparent content of K⁺ Cl¹. Hypo-osmolarity had no effect on the ouabain-sensitive portion of the Rb⁺ influx (Na⁺/K⁺ pump), but reduced the ouabain-resistant portion of the influx. Hypo-osmolarity also strongly increased the Rb⁺ efflux rate. Both tetracaine (0.5 mitt) and glibenclamide (20 μM), which increase the osmotic resistance of pancreatic β cells, significantly potentiated the reduction in apparent K⁺ content induced by hypo-osmolarity. This study suggests that the volume regulation in pancreatic β cells is partly due to K⁺ Cl^- flux and that glibenclamide and tetracaine increase the osmotic resistance of the β cells by affecting such ion transport.     

Cellular composition of pancreas-associated lymphoid tissue during human fetal pancreatic development

AIM: To study human fetal pancreatic tissue between 15 weeks of gestation and term, analysing the development of pancreatic lymphoid tissue and focusing on the presence and maturational status of dendritic cells (DCs). During normal human fetal pancreatic development lymphoid tissue arises in and around the pancreas. DCs are antigen-presenting cells which are capable of initiating immunity, but are also essential in inducing and maintaining T-cell tolerance. METHODS AND RESULTS: First, the presence and general composition of intra- and peripancreatic lymphoid tissue was investigated by histology and immunohistochemistry with antibodies to CD3, CD4, CD8, CD14, CD20, CD68, and CD79. Intrapancreatic lymphoid tissue (IPLT) appeared to be present only from 29 weeks of gestation onwards, and had a similar composition to peripancreatic lymphoid tissue (PPLT), which was found in all 23 specimens examined. Both forms of lymphoid tissue had an architecture similar to lymph nodes, with separate B- and T-lymphocyte areas and scattered macrophages. DCs were investigated in detail by immunohistochemistry for CD1a, CD83, CD86, CD123, Langerin, and DC-LAMP. Both Langerin, a marker for immature DCs, as well as DC-LAMP, a marker for mature DCs, were expressed by cells in both the IPLT and PPLT at all ages examined. CONCLUSION: The presence of DCs at all developmental stages, expressing various maturation-related markers, in addition to the general composition of the human fetal PPLT and IPLT suggests that this is fully functional and has a function comparable to peripheral lymph nodes.     

In vitro development of B cells and macrophages from early mouse fetal thymocytes

The developmental potentialities of early mouse fetal thymocytes were analyzed by in vitro culturing cell suspensions obtained from 12–15-gestational day thymus in contact with a bone marrow stroma clonal cell line that supports pre-B and myeloid cell differentiation. B cell and macrophage development from fetal thymocytes was observed at all fetal stages tested, but limiting dilution analysis revealed that the frequency of cells forming colonies on bone marrow stroma is the highest in the fetal thymus at day 12, then dramatically decreases until day 15. These observations suggest that the thymus rudiment is seeded by multipotential precursor cells which are not immediately committed to T cell development in the thymic cellular environment.     

Cytochalasin B: Evidence for a membrane-directed action in B-cells from rat pancreatic islets

Summary In the presence of cytochalasin B (CCB) concentrations from 50 to 200 g/ml there is a dose-dependant inhibition of insulin release from isolated rat pancreatic islets. Inhibition is unspecific with respect to glucose, leucine, tolbutamide or theophylline and is reversible. Production of¹⁴CO₂ from uniformly labeled D-glucose is decreased. Islets pretreated with an high (200 g/ml) or low (10 g/ml) CCB dose release more insulin in response to a subsequent glucose or leucine stimulus in a CCB free medium compared with controls. The data are compatible with a membrane-directed action of CCB.     

Antioxidant probucol prevents development of alloxan diabetes and hypoactivity of antioxidant enzymes in rat tissues

All-Union Cardiologic Scientific Center, Russian Academy of Medical Sciences, Moscow, Karaganda Medical Institute. All-Union Scientific Center for Safety of Biologically Active Substances, Kupavna. (Presented by Academician of the Russian Academy of Medical Sciences E. I. Chazov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 9, pp. 279–282, September, 1992.