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Pancreatic Development (pancreatic + development)
Selected AbstractsImmunohistochemistry of Pancreatic Development in Cattle and PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2010G. L. Carlsson Summary With 8 figures and 2 tables The aim of this study was to characterize bovine and porcine pancreatic development by immunohistochemistry. In the pig, staining for both glucagon and insulin was noted at day 19. In cattle, glucagon staining was observed at day 25 and insulin staining from day 26. In both species, glucagon-stained cells were abundant initially, but later insulin-stained cells became most abundant. A few cells displayed co-localization of glucagon and insulin staining during initial development in both species. Initially, most of the cells of the pancreatic primordia and the duodenal epithelium displayed Pdx-1-staining. All insulin-stained cells displayed Pdx-1-stained nuclei, whereas no glucagon-stained cells did so. Many Pdx-1-stained cells lacked insulin staining, but with development, the relative number of these cells diminished. Nkx6.1-staining was initially seen in a pattern similar to that for Pdx-1, but was lacking duodenal staining. Subsequently, the number of Nkx6.1-stained cells diminished, but increased again to a level where practically all insulin-stained cells also presented Nkx6.1-staining. Glucagon-stained cells, on the other hand, never had Nkx6.1 staining. In conclusion, the localization of the two transcription factors, Pdx-1 and Nkx6.1, demonstrated that pancreas development appears to be controlled by mechanisms comparable with those operating in humans. [source] Characterization of primary cilia and Hedgehog signaling during development of the human pancreas and in human pancreatic duct cancer cell linesDEVELOPMENTAL DYNAMICS, Issue 8 2008Sonja K. Nielsen Abstract Hedgehog (Hh) signaling controls pancreatic development and homeostasis; aberrant Hh signaling is associated with several pancreatic diseases. Here we investigated the link between Hh signaling and primary cilia in the human developing pancreatic ducts and in cultures of human pancreatic duct adenocarcinoma cell lines, PANC-1 and CFPAC-1. We show that the onset of Hh signaling from human embryogenesis to fetal development is associated with accumulation of Hh signaling components Smo and Gli2 in duct primary cilia and a reduction of Gli3 in the duct epithelium. Smo, Ptc, and Gli2 localized to primary cilia of PANC-1 and CFPAC-1 cells, which may maintain high levels of nonstimulated Hh pathway activity. These findings indicate that primary cilia are involved in pancreatic development and postnatal tissue homeostasis. Developmental Dynamics 237:2039,2052, 2008. © 2008 Wiley-Liss, Inc. [source] Analysis of pancreatic endocrine development in GDF11-deficient miceDEVELOPMENTAL DYNAMICS, Issue 11 2006Darwin S. Dichmann Abstract Here, we examine the role of GDF11 in pancreatic development. Using in situ hybridization and reverse transcriptase-polymerase chain reaction analyses, we show that Gdf11 transcripts are expressed in embryonic pancreas epithelium before the secondary transition but decrease rapidly afterward. To determine the function of GDF11 during pancreas development, we analyzed Gdf11,/, mouse embryos. In such embryos, pancreas size is twofold reduced at embryonic day (E) 18 compared with wild-type littermates. Quantification of the different tissue compartments shows a specific hypoplasia of the exocrine compartment, while the endocrine and ductal compartments are unaffected. Notably, NGN3+ endocrine precursor cells are increased fourfold at E18, although the amount of endocrine cells in the pancreas of these animals is unchanged compared with wild-type littermates. Similarly, the maturation of endocrine cells as well as the ratio between ,- and ,-cells appears normal. Developmental Dynamics 235:3016,3025, 2006. © 2006 Wiley-Liss, Inc. [source] ,-cell development: the role of intercellular signalsDIABETES OBESITY & METABOLISM, Issue 2008R. Scharfmann Understanding in detail how pancreatic endocrine cells develop is important for many reasons. From a scientific point of view, elucidation of such a complex process is a major challenge. From a more applied point of view, this may help us to better understand and treat specific forms of diabetes. Although a variety of therapeutic approaches are well validated, no cure for diabetes is available. Many arguments indicate that the development of new strategies to cure diabetic patients will require precise understanding of the way ,-cells form during development. This is obvious for a future cell therapy using ,-cells produced from embryonic stem cells. This also holds true for therapeutic approaches based on regenerative medicine. In this review, we summarize our current knowledge concerning pancreatic development and focus on the role of extracellular signals implicated in ,-cell development from pancreatic progenitors. [source] Progenitor cells in the adult pancreasDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 1 2004Andrew M. Holland Abstract The ,-cell mass in the adult pancreas possesses the ability to undergo limited regeneration following injury. Identifying the progenitor cells involved in this process and understanding the mechanisms leading to their maturation will open new avenues for the treatment of type 1 diabetes. However, despite steady advances in determining the molecular basis of early pancreatic development, the identification of pancreatic stem cells or ,-cell progenitors and the molecular mechanisms underlying ,-cell regeneration remain unclear. Recent advances in the directed differentiation of embryonic and adult stem cells has heightened interest in the possible application of stem cell therapy in the treatment of type 1 diabetes. Drawing on the expanding knowledge of pancreas development, ,-cell regeneration and stem cell research, this review focuses on progenitor cells in the adult pancreas as a potential source of ,-cells. Copyright © 2004 John Wiley & Sons, Ltd. [source] Immunohistochemistry of Pancreatic Development in Cattle and PigANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2010G. L. Carlsson Summary With 8 figures and 2 tables The aim of this study was to characterize bovine and porcine pancreatic development by immunohistochemistry. In the pig, staining for both glucagon and insulin was noted at day 19. In cattle, glucagon staining was observed at day 25 and insulin staining from day 26. In both species, glucagon-stained cells were abundant initially, but later insulin-stained cells became most abundant. A few cells displayed co-localization of glucagon and insulin staining during initial development in both species. Initially, most of the cells of the pancreatic primordia and the duodenal epithelium displayed Pdx-1-staining. All insulin-stained cells displayed Pdx-1-stained nuclei, whereas no glucagon-stained cells did so. Many Pdx-1-stained cells lacked insulin staining, but with development, the relative number of these cells diminished. Nkx6.1-staining was initially seen in a pattern similar to that for Pdx-1, but was lacking duodenal staining. Subsequently, the number of Nkx6.1-stained cells diminished, but increased again to a level where practically all insulin-stained cells also presented Nkx6.1-staining. Glucagon-stained cells, on the other hand, never had Nkx6.1 staining. In conclusion, the localization of the two transcription factors, Pdx-1 and Nkx6.1, demonstrated that pancreas development appears to be controlled by mechanisms comparable with those operating in humans. [source] | |||||||||||||