scholarly journals Type 1 Diabetes: Interferons and the Aftermath of Pancreatic Beta-Cell Enteroviral Infection

2020 ◽  
Vol 8 (9) ◽  
pp. 1419
Author(s):  
Pouria Akhbari ◽  
Sarah J Richardson ◽  
Noel G Morgan
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Pancreatic Beta Cells ◽  
Growth Regulation ◽  
Cell Function ◽  
Viral Infections ◽  
Pancreatic Beta Cell ◽  
Enteroviral Infection ◽  
Cellular Processes

Enteroviruses (EVs) have long been implicated in the pathogenesis of type 1 diabetes (T1D), and accumulating evidence has associated virus-induced autoimmunity with the loss of pancreatic beta cells in T1D. Inflammatory cytokines including interferons (IFN) form a primary line of defence against viral infections, and their chronic elevation is a hallmark feature of many autoimmune diseases. IFNs play a key role in activating and regulating innate and adaptive immune responses, and to do so they modulate the expression of networks of genes and transcription factors known generically as IFN stimulated genes (ISGs). ISGs in turn modulate critical cellular processes ranging from cellular metabolism and growth regulation to endoplasmic reticulum (ER) stress and apoptosis. More recent studies have revealed that IFNs also modulate gene expression at an epigenetic as well as post-transcriptional and post-translational levels. As such, IFNs form a key link connecting the various genetic, environmental and immunological factors involved in the initiation and progression of T1D. Therefore, gaining an improved understanding of the mechanisms by which IFNs modulate beta cell function and survival is crucial in explaining the pathogenesis of virally-induced T1D. This should provide the means to prevent, decelerate or even reverse beta cell impairment.

scholarly journals The acquisition of an insulin-secreting phenotype by HGF-treated rat pancreatic ductal cells (ARIP) is associated with the development of susceptibility to cytokine-induced apoptosis

2005 ◽  
Vol 34 (2) ◽  
pp. 367-376 ◽  
Author(s):  
E Anastasi ◽  
C Santangelo ◽  
A Bulotta ◽  
F Dotta ◽  
B Argenti ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Pancreatic Beta Cells ◽  
Interleukin 1 ◽  
Pancreatic Beta Cell ◽  
Necrosis Factor Alpha ◽  
Ductal Cells ◽  
Pancreatic Ductal Cells ◽  
Induced Apoptosis

The elucidation of mechanisms regulating the regeneration and survival of pancreatic beta cells has fundamental implications in the cell therapy of type 1 diabetes. The present study had the following three aims: 1. to investigate whether pancreatic ductal epithelial cells can be induced to differentiate into insulin-producing cells by exposing them to hepatocyte growth factor (HGF); 2. to characterize some of the molecular events leading to their differentiation toward a beta-cell-like phenotype; 3. to evaluate the susceptibility of newly differentiated insulin-secreting cells to cytokine-induced apoptosis, a mechanism of beta-cell destruction occurring in type 1 diabetes. We demonstrated that HGF-treated rat pancreatic ductal cell line (ARIP) cells acquired the capability to transcribe the insulin gene and translate its counterpart protein. HGF-treated cells also exhibited a glucose-dependent capability to secrete insulin into the cultured medium. Expression analysis of some of the genes regulating pancreatic beta-cell differentiation revealed a time-dependent transcription of neurogenin-3 and Neuro-D in response to HGF. Finally, we determined the susceptibility to proinflammatory cytokine (PTh1)-induced apoptosis by incubating HGF-treated and untreated ARIP cells with a cocktail of interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ). Such treatment induced apoptotic death, as determined by the TUNEL technique, in about 40% of HGF-treated, insulin-secreting ARIP cells, while untreated ARIP cells were resistant to PTh1-induced apoptosis. In conclusion, we showed that HGF promotes the differentiation of ARIP cells into pancreatic beta-cell-like cells, and that the differentiation toward an insulin-secreting phenotype is associated with the appearance of susceptibility to cytokine-induced apoptosis.

Vitamin D supplementation induces CatG-mediated CD4+ T cell inactivation and restores pancreatic beta-cell function in mice with type 1 diabetes

2021 ◽  
Author(s):  
Xiaoyang Lai ◽  
Xuyang Liu ◽  
Xia Cai ◽  
Fang Zou
Keyword(s):  
Vitamin D ◽  
Type 1 Diabetes ◽  
Beta Cell ◽  
Cell Function ◽  
Pancreatic Beta Cell ◽  
Pancreatic Β Cell ◽  
Β Cell ◽  
Β Cell Function

Type 1 diabetes (T1D) is a chronic autoimmune disease accompanied by the immune-mediated destruction of pancreatic β-cells. In this study, we aimed to explore the regulatory effects of Vitamin D (VD) supplementation on pancreatic β-cell function by altering the expression of bioinformatically identified cathepsin G (CatG) in T1D model mice. A T1D mouse model was established in non-obese diabetic (NOD) mice, and their islets were isolated and purified. Pancreatic mononuclear cells (MNCs) were collected, from which CD4+ T cells were isolated. The levels of interleukin (IL)-2, IL-10, tumor necrosis factor-α (TNF-α) and interferon-gamma (IFN-γ) in the supernatant of mouse pancreatic tissue homogenate were assessed using ELISA. Immunohistochemistry and TUNEL staining were conducted to evaluate the effects of VD supplementation on pancreatic tissues of T1D mice. The pancreatic beta-cell line MIN6 was used for in vitro substantiation of findings in vivo. VD supplementation reduced glucose levels and improved glucose tolerance in T1D mice. Further, VD supplementation improved pancreatic β-cell function and suppressed immunological and inflammatory reactions in the T1D mice. We documented overexpression of CatG in diabetes tissue samples, and then showed that VD supplementation normalized the islet immune microenvironment through down-regulating CatG expression in T1D mice. Experiments in vitro subsequently demonstrated that VD supplementation impeded CD4+ T activation by down-regulating CatG expression, and thereby enhanced pancreatic β-cell function. Results of the present study elucidated that VD supplementation can down-regulate the expression of CatG and inhibit CD4+ T cell activation, thereby improving β-cell function in T1D.

scholarly journals Mediators and mechanisms of pancreatic beta-cell death in type 1 diabetes

2008 ◽  
Vol 52 (2) ◽  
pp. 156-165 ◽  
Author(s):  
Pierre Pirot ◽  
Alessandra K. Cardozo ◽  
Décio L. Eizirik
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Beta Cells ◽  
Pancreatic Beta Cells ◽  
Map Kinases ◽  
Pancreatic Beta Cell ◽  
Insulin Deficiency ◽  
Beta Cell Destruction ◽  
Pro Inflammatory Cytokines

Type 1 diabetes mellitus (T1D) is characterized by severe insulin deficiency resulting from chronic and progressive destruction of pancreatic beta-cells by the immune system. The triggering of autoimmunity against the beta-cells is probably caused by environmental agent(s) acting in the context of a predisposing genetic background. Once activated, the immune cells invade the islets and mediate their deleterious effects on beta-cells via mechanisms such as Fas/FasL, perforin/granzyme, reactive oxygen and nitrogen species and pro-inflammatory cytokines. Binding of cytokines to their receptors on the beta-cells activates MAP-kinases and the transcription factors STAT-1 and NFkappa-B, provoking functional impairment, endoplasmic reticulum stress and ultimately apoptosis. This review discusses the potential mediators and mechanisms leading to beta-cell destruction in T1D.

scholarly journals Serum miR-204 is an early biomarker of type 1 diabetes-associated pancreatic beta-cell loss

2019 ◽  
Vol 317 (4) ◽  
pp. E723-E730 ◽  
Author(s):  
Guanlan Xu ◽  
Lance A. Thielen ◽  
Junqin Chen ◽  
Truman B. Grayson ◽  
Tiffany Grimes ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Beta Cells ◽  
Cell Function ◽  
Pancreatic Beta Cell ◽  
Cell Loss ◽  
Human Islets ◽  
Serum Samples ◽  
Early Biomarker

Pancreatic beta-cell death is a major factor in the pathogenesis of type 1 diabetes (T1D), but straightforward methods to measure beta-cell loss in humans are lacking, underlining the need for novel biomarkers. Using studies in INS-1 cells, human islets, diabetic mice, and serum samples of subjects with T1D at different stages, we have identified serum miR-204 as an early biomarker of T1D-associated beta-cell loss in humans. MiR-204 is a highly enriched microRNA in human beta-cells, and we found that it is released from dying beta-cells and detectable in human serum. We further discovered that serum miR-204 was elevated in children and adults with T1D and in autoantibody-positive at-risk subjects but not in type 2 diabetes or other autoimmune diseases and was inversely correlated with remaining beta-cell function in recent-onset T1D. Thus, serum miR-204 may provide a much needed novel approach to assess early T1D-associated human beta-cell loss even before onset of overt disease.

294-OR: Type 1 Diabetes Patients with Residual Beta-Cell Function Display Improved Time in Euglycemia and Less Glycaemic Fluctuation after Exercise

Diabetes ◽  
2019 ◽  
Vol 68 (Supplement 1) ◽  
pp. 294-OR
Author(s):  
GUY S. TAYLOR ◽  
KIERAN SMITH ◽  
JADINE SCRAGG ◽  
AYAT BASHIR ◽  
RICHARD A. ORAM ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
Beta Cell ◽  
Beta Cell Function ◽  
Cell Function ◽  
Diabetes Patients
Sign in / Sign up

Export Citation Format

Share Document