• Title/Summary/Keyword: pancreatic islet $\alpha$ -cell

Search Result 8, Processing Time 0.021 seconds

Expression Profile and Potential Roles of EVA1A in Normal and Neoplastic Pancreatic Tissues

  • Tao, Ming;Shi, Xue-Ying;Yuan, Chun-Hui;Hu, Jia;Ma, Zhao-Lai;Jiang, Bin;Xiu, Dian-Rong;Chen, Ying-Yu
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.1
    • /
    • pp.373-376
    • /
    • 2015
  • Background: EVA1A (eva-1 homolog A) is a novel gene that regulates programmed cell death through autophagy and apoptosis. Our objective was to investigate the expression profiles and potential role of EVA1A in normal and neoplastic human pancreatic tissues. Materials and Methods: The expression pattern of EVA1A in normal pancreatic tissue was examined by indirect immunofluorescence and confocal microscopy. Protein levels in paraffin-embedded specimens from normal and diseased pancreatic and matched non-tumor tissues were evaluated by immunohistochemistry. Results: EVA1A colocalized with glucagon but not with insulin, demonstrating production in islet alpha cells. Itwas strongly expressed in chronic pancreatitis, moderately or weakly expressed in the plasma membrane and cytoplasm in pancreatic acinar cell carcinoma, and absent in normal pancreatic acinar cells. Although the tissue architecture was deformed, EVA1A was absent in the alpha cells of pancreatic ductal adenocarcinomas, intraductal papillary mucinous neoplasms, mucinous cystadenomas, solid papillary tumors and pancreatic neuroendocrine tumors. Conclusions: EVA1A protein is specifically expressed in islet alpha cells, suggesting it may play an important role in regulating alpha-cell function. The ectopic expression of EVA1A in pancreatic neoplasms may contribute to their pathogenesis and warrants further investigation.

Expression of c-Jun in pancreatic islet $\alpha$-cells of nonobese diabetic(NOD) mice

  • Park, Sang-Joon;Lee, Sae-Bom;Choi, Yang-Kyu;Lee, Chul-Ho;Hyun, Byung-Hwa;Lee, Keun-Joa;Ryu, Si-Yun;Cho, Sung-Whan;Song, Jae-Chan;Lee, Cha-Soo;Jeong, Kyu-Shik
    • Korean Journal of Veterinary Pathology
    • /
    • v.2 no.1
    • /
    • pp.17-24
    • /
    • 1998
  • This is the first report of c-Jun protein expression and mRNA in a pancreatic islet in a nonobese diabetic(NOD) state mice. In this experiment NOD mice with insulin-dependent diabetes mellitus type I at age 16 weeks(n=7) just before death(n=4) were used. The control group consist of prediabetic NOD(8 weeks n=7) and ICR(8 weeks n=7 and 16 weeks n=7) mice. c-Jun positive cells in the pancreatic islet of NOD mice were localized in the same positions as a-glucagon producing cells. immunoreactivity was negative in the prediabetic NOD(8 weeks) and ICR(8 weeks and 16 weeks) mice. The number of c-Jun positive cells in mice with severe diabetic state just before death were significantly decreased when compared to NOD(16 weeks) mice. Expression of c-Jun in mRNA level was assessed by RT-PCR method. The levels of mRNA in NOD(16 weeks) mice group were elevated in total pancreatic tissues. The present results suggest that the induction of proto-oncogene protein may be of significance in assessing cell specific injury and may play a functional role between pancretic islet $\alpha$-cells and $\beta$-cells in the diabetic state.

  • PDF

Apoptosis of Human Islet Cells by Cytokines

  • Kim, Sun-Shin;Kim, Kyoung-Ah;Suk, Kyoung-Ho;Kim, Yun-Hee;Oh, Seung-Hoon;Lee, Moon-Kyu;Kim, Kwang-Won;Lee, Myung-Shik
    • IMMUNE NETWORK
    • /
    • v.12 no.3
    • /
    • pp.113-117
    • /
    • 2012
  • FasL, perforin, $TNF{\alpha}$, IL-1 and NO have been considered as effector molecule(s) leading to ${\beta}$-cell death in autoimmune diabetes. However, the real culprit(s) of ${\beta}$-cell destruction have long been elusive despite intense investigation. Previously we have suggested $IFN{\gamma}/TNF{\alpha}$ synergism as the final effector molecules in autoimmune diabetes of NOD mice. A combination of $IFN{\gamma}$ and $TNF{\alpha}$ but neither cytokine alone, induced classical caspase-dependent apoptosis in murine insulinoma and pancreatic islet cells. $IFN{\gamma}$ treatment conferred susceptibility to $TNF{\alpha}$-induced apoptosis on otherwise resistant murine insulinoma cells by STAT1 activation followed by IRF-1 induction. Here we report that $IFN{\gamma}/TNF{\alpha}$ synergism induces apoptosis of human pancreatic islet cells. We also observed STAT1 activation followed by IRF-1 induction by $IFN{\gamma}$ treatment in human islet cells. Taken together, we suggest that $IFN{\gamma}/TNF{\alpha}$ synergism could be involved in human islet cell death in type 1 diabetes, similar to murine type 1 diabetes.

Cytokine Synergism in Apoptosis: Its Role in Diabetes and Cancer

  • Lee, Myung-Shik
    • BMB Reports
    • /
    • v.35 no.1
    • /
    • pp.54-60
    • /
    • 2002
  • The effects of individual cytokine on apoptosis have been extensively studied. However, the effect of the cytokine combination, or the synergistic effect of cytokines on cell death, has not been widely studied, though synergism between cytokines has been documented in a variety of biological situations. In our effort to identify the final death effector molecule(s) in autoimmune diabetes, we inadvertently became interested in the cytokine synergism. We discovered that $IFN{\gamma}/TNF{\alpha}$ synergism, rather than the Fas ligand as currently believed, is responsible for the apoptosis of pancreatic islet cells both in vitro and in vivo. We also studied similar cytokine synergism in cancer cell deaths, and noted the similarities and dissimilarities between cancer cell death and islet cell death.

Short-Term High Expression of Interferon-Alpha Modulates Progression of Type 1 Diabetes in NOD Mice

  • Park, Mi-Kyoung;Seo, Su-Yeong;Hong, Sook-Hee;Kim, Hye-Jin;Park, Eun-Jin;Kim, Duk-Kyu;Lee, Hye-Jeong
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.10 no.1
    • /
    • pp.39-44
    • /
    • 2006
  • Type I diabetes (T1D) is an organ-specific autoimmune disease caused by the T cell-mediated destruction of the insulin-producing ${\beta}$ cells in the pancreatic islets. The onset of T1D is the consequence of a progressive destruction of islet ${\beta}$ cells mediated by an imbalance between effector $CD4^+$ T helper (Th)1 and regulatory $CD4^+$ Th2 cell function. Since interferon-alpha (IFN-${\alpha}$) has been known to modulate immune function and autoimmunity, we investigated whether administration of adenoviralmediated IFN-${\alpha}$ gene would inhibit the diabetic process in NOD mice. The development of diabetes was significantly inhibited by a single injection of adenoviral-mediated IFN-${\alpha}$ gene before 8 weeks of age. Next, we examined the hypothesis that Th2-type cytokines are associated with host protection against autoimmune diabetes, whereas Th1-type cytokines are associated with pathogenesis of T1D. The expression of IFN-${\alpha}$ induced increase of serum IL-4 and IL-6 (Th2 cytokines) levels and decrease of serum IL-12 and IFN-${\gamma}$ (Th1 cytokines) levels. Therefore, overexpression of IFN-${\alpha}$ by adenoviralmediated delivery provides modulation of pathogenic progression and protection of NOD mice from T1D.

Transdifferentiation of α-1,3-Galactosyltransferase Knock Out (GalT KO) Pig Derived Bone Marrow Mesenchymal Stromal Cells (BM-MSCs) into Pancreatic Cells by Transfection of hPDX1 (hPDX1 유전자의 삽입에 의한 직접 췌도세포 분화)

  • Ock, Sun A;Oh, Keon Bong;Hwang, Seongsoo;Kim, Youngim;Kwon, Dae-Jin;Im, Gi-Sun
    • Journal of Embryo Transfer
    • /
    • v.30 no.3
    • /
    • pp.249-255
    • /
    • 2015
  • Diabetes mellitus, the most common metabolic disorder, is divided into two types: type 1 and type 2. The essential treatment of type 1 diabetes, caused by immune-mediated destruction of ${\beta}-cells$, is transplantation of the pancreas; however, this treatment is limited by issues such as the lack of donors for islet transplantation and immune rejection. As an alternative approach, stem cell therapy has been used as a new tool. The present study revealed that bone marrowderived mesenchymal stromal cells (BM-MSCs) could be transdifferentiated into pancreatic cells by the insertion of a key gene for embryonic development of the pancreas, the pancreatic and duodenal homeobox factor 1 (PDX1). To avoid immune rejection associated with xenotransplantation and to develop a new cell-based treatment, BM-MSCs from ${\alpha}$-1,3-galactosyltransferase knockout (GalT KO) pigs were used as the source of the cells. Transfection of the EGFP-hPDX1 gene into GalT KO pig-derived BM-MSCs was performed by electroporation. Cells were evaluated for hPDX1 expression by immunofluorescence and RT-PCR. Transdifferentiation into pancreatic cells was confirmed by morphological transformation, immunofluorescence, and endogenous pPDX1 gene expression. At 3~4 weeks after transduction, cell morphology changed from spindle-like shape to round shape, similar to that observed in cuboidal epithelium expressing EGFP. Results of RT-PCR confirmed the expression of both exogenous hPDX1 and endogenous pPDX1. Therefore, GalT KO pig-derived BM-MSCs transdifferentiated into pancreatic cells by transfection of hPDX1. The present results are indicative of the therapeutic potential of PDX1-expressing GalT KO pig-derived BM-MSCs in ${\beta}-cell$ replacement. This potential needs to be explored further by using in vivo studies to confirm these findings.

In vivo multiplex gene targeting with Streptococcus pyogens and Campylobacter jejuni Cas9 for pancreatic cancer modeling in wild-type animal

  • Chang, Yoo Jin;Bae, Jihyeon;Zhao, Yang;Lee, Geonseong;Han, Jeongpil;Lee, Yoon Hoo;Koo, Ok Jae;Seo, Sunmin;Choi, Yang-Kyu;Yeom, Su Cheong
    • Journal of Veterinary Science
    • /
    • v.21 no.2
    • /
    • pp.26.1-26.14
    • /
    • 2020
  • Pancreatic ductal adenocarcinoma is a lethal cancer type that is associated with multiple gene mutations in somatic cells. Genetically engineered mouse is hardly applicable for developing a pancreatic cancer model, and the xenograft model poses a limitation in the reflection of early stage pancreatic cancer. Thus, in vivo somatic cell gene engineering with clustered regularly interspaced short palindromic repeats is drawing increasing attention for generating an animal model of pancreatic cancer. In this study, we selected Kras, Trp53, Ink4a, Smad4, and Brca2 as target genes, and applied Campylobacter jejuni Cas9 (CjCas9) and Streptococcus pyogens Cas9 (SpCas9) for developing pancreatic cancer using adeno associated virus (AAV) transduction. After confirming multifocal and diffuse transduction of AAV2, we generated SpCas9 overexpression mice, which exhibited high double-strand DNA breakage (DSB) in target genes and pancreatic intraepithelial neoplasia (PanIN) lesions with two AAV transductions; however, wild-type (WT) mice with three AAV transductions did not develop PanIN. Furthermore, small-sized Cjcas9 was applied to WT mice with two AAV system, which, in addition, developed high extensive DSB and PanIN lesions. Histological changes and expression of cancer markers such as Ki67, cytokeratin, Mucin5a, alpha smooth muscle actin in duct and islet cells were observed. In addition, the study revealed several findings such as 1) multiple DSB potential of AAV-CjCas9, 2) peri-ductal lymphocyte infiltration, 3) multi-focal cancer marker expression, and 4) requirement of > 12 months for initiation of PanIN in AAV mediated targeting. In this study, we present a useful tool for in vivo cancer modeling that would be applicable for other disease models as well.

Sphingosine 1-phosphate induces vesicular endothelial growth factor expression in endothelial cells

  • Heo, Kyun;Park, Kyung-A;Kim, Yun-Hee;Kim, Sun-Hee;Oh, Yong-Seok;Kim, In-Hoo;Ryu, Sung-Ho;Suh, Pann-Ghill
    • BMB Reports
    • /
    • v.42 no.10
    • /
    • pp.685-690
    • /
    • 2009
  • Angiogenesis is essential for tumor growth and vascular endothelial cell growth factor (VEGF) plays a key role in this process. Conversely, sphingosine 1-phosphate (S1P) is a biologically active sphingolipid known to play a key role in cancer progression by regulating endothelial cell proliferation and migration. In this study, the authors found that S1P increases the level of VEGF mRNA in human umbilical vein endothelial cells (HUVECs) and immortalized HUVECs (iHUVECs). Additionally, S1P was found to increase VEGF promoter activity in MS-1 mouse pancreatic islet endothelial cells. Furthermore, a pharmacological inhibitory study revealed that $G_{\alpha i/o}$-mediated phospholipase C, Akt, Erk, and p38 MAPK signaling are involved in this S1P-induced expression of VEGF. A component of AP1 transcription factor is important for S1P-induced VEGF expression. Taken together, these findings suggest that S1P enhances endothelial cell proliferation and migrat ion by upregulating the expression of VEGF mRNA.