scholarly journals Role of Hck in the Pathogenesis of Encephalomyocarditis Virus-Induced Diabetes in Mice

2001 ◽  
Vol 75 (4) ◽  
pp. 1949-1957 ◽  
Author(s):  
K. S. Choi ◽  
H. S. Jun ◽  
H. N. Kim ◽  
H. J. Park ◽  
Y. W. Eom ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Low Dose ◽  
Kinase Inhibitor ◽  
Src Kinase ◽  
Encephalomyocarditis Virus ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Necrosis Factor Alpha ◽  
Diabetes In Mice ◽  
Tnf Α

ABSTRACT Soluble mediators such as interleukin-1β, tumor necrosis factor alpha (TNF-α), and inducible nitric oxide synthase (iNOS) produced from activated macrophages play an important role in the destruction of pancreatic β cells in mice infected with a low dose of the D variant of encephalomyocarditis (EMC-D) virus. The tyrosine kinase signaling pathway was shown to be involved in EMC-D virus-induced activation of macrophages. This investigation was initiated to determine whether the Src family of kinases plays a role in the activation of macrophages, subsequently resulting in the destruction of β cells, in mice infected with a low dose of EMC-D virus. We examined the activation of p59/p56Hck, p55Fgr, and p56/p53Lynin macrophages from DBA/2 mice infected with the virus. We found that p59/p56Hck showed a marked increase in both autophosphorylation and kinase activity at 48 h after infection, whereas p55Fgr and p56/p53Lyn did not. The p59/p56Hck activity was closely correlated with the tyrosine phosphorylation level of Vav. Treatment of EMC-D virus-infected mice with the Src kinase inhibitor, PP2, resulted in the inhibition of p59/p56Hck activity and almost complete inhibition of the production of TNF-α and iNOS in macrophages and the subsequent prevention of diabetes in mice. On the basis of these observations, we conclude that the Src kinase, p59/p56Hck, plays an important role in the activation of macrophages and the subsequent production of TNF-α and nitric oxide, leading to the destruction of pancreatic β cells, which results in the development of diabetes in mice infected with a low dose of EMC-D virus.

scholarly journals Role of Nitric Oxide in the Pathogenesis of Encephalomyocarditis Virus-Induced Diabetes in Mice

2009 ◽  
Vol 83 (16) ◽  
pp. 8004-8011 ◽  
Author(s):  
Young-Sun Lee ◽  
Na Li ◽  
Seungjin Shin ◽  
Hee-Sook Jun
Keyword(s):  
Virus Infection ◽  
Encephalomyocarditis Virus ◽  
Wild Type ◽  
Β Cells ◽  
Β Cell ◽  
Pancreatic Β Cells ◽  
Diabetes In Mice ◽  
Tnf Α ◽  
Deficient Mice

ABSTRACT The D variant of encephalomyocarditis virus (EMC-D virus) causes diabetes in mice by destroying pancreatic β cells. In mice infected with a low dose of EMC-D virus, macrophages play an important role in β-cell destruction by producing soluble mediators such as interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), and nitric oxide (NO). To investigate the role of NO and inducible NO synthase (iNOS) in the development of diabetes in EMC-D virus-infected mice, we infected iNOS-deficient DBA/2 mice with EMC-D virus (2 × 102 PFU/mouse). Mean blood glucose levels in EMC-D virus-infected iNOS-deficient mice and wild-type mice were 205.5 and 466.7 mg/dl, respectively. Insulitis and macrophage infiltration were reduced in islets of iNOS-deficient mice compared with wild-type mice at 3 days after EMC-D virus infection. Apoptosis of β cells was decreased in iNOS-deficient mice, as evidenced by reduced numbers of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cells. There were no differences in mRNA expression of antiapoptotic molecules Bcl-2, Bcl-xL, Bcl-w, Mcl-1, cIAP-1, and cIAP-2 between wild-type and iNOS-deficient mice, whereas expression of proapoptotic Bax and Bak mRNAs was significantly decreased in iNOS-deficient mice. Expression of IL-1β and TNF-α mRNAs was significantly decreased in both islets and macrophages of iNOS-deficient mice compared with wild-type mice after EMC-D virus infection. Nuclear factor κB was less activated in macrophages of iNOS-deficient mice after virus infection. We conclude that NO plays an important role in the activation of macrophages and apoptosis of pancreatic β cells in EMC-D virus-infected mice and that deficient iNOS gene expression inhibits macrophage activation and β-cell apoptosis, contributing to prevention of EMC-D virus-induced diabetes.

scholarly journals Nitric oxide interacts with cholinoceptors to modulate insulin secretion by pancreatic β cells

2020 ◽  
Vol 472 (10) ◽  
pp. 1469-1480
Author(s):  
Bashair M. Mussa ◽  
Ankita Srivastava ◽  
Abdul Khader Mohammed ◽  
Anthony J. M. Verberne
Keyword(s):  
Nitric Oxide ◽  
Insulin Secretion ◽  
Cell Viability ◽  
Combined Treatment ◽  
No Production ◽  
Β Cells ◽  
Β Cell ◽  
Pancreatic Β Cells ◽  
Tnf Α ◽  
Ifn Γ

Abstract Dysfunction of the pancreatic β cells leads to several chronic disorders including diabetes mellitus. Several mediators and mechanisms are known to be involved in the regulation of β cell secretory function. In this study, we propose that cytokine-induced nitric oxide (NO) production interacts with cholinergic mechanisms to modulate insulin secretion from pancreatic β cells. Using a rat insulinoma cell line INS-1, we demonstrated that β cell viability decreases significantly in the presence of SNAP (NO donor) in a concentration- and time-dependent manner. Cell viability was also found to be decreased in the presence of a combined treatment of SNAP with SMN (muscarinic receptor antagonist). We then investigated the impact of these findings on insulin secretion and found a significant reduction in glucose uptake by INS-1 cells in the presence of SNAP and SMN as compared with control. Nitric oxide synthase 3 gene expression was found to be significantly reduced in response to combined treatment with SNAP and SMN suggesting an interaction between the cholinergic and nitrergic systems. The analysis of gene and protein expression further pin-pointed the involvement of M3 muscarinic receptors in the cholinergic pathway. Upon treatment with cytokines, reduced cell viability was observed in the presence of TNF-α and IFN-γ. A significant reduction in insulin secretion was also noted after treatment with TNF-α and IFN-γ and IL1-β. The findings of the present study have shown for the first time that the inhibition of the excitatory effects of cholinergic pathways on glucose-induced insulin secretion may cause β cell injury and dysfunction of insulin secretion in response to cytokine-induced NO production.

Dual effect of nitric oxide on cytosolic Ca2+concentration and insulin secretion in rat pancreatic β-cells

2003 ◽  
Vol 284 (5) ◽  
pp. C1215-C1222 ◽  
Author(s):  
Yukiko Kaneko ◽  
Tomohisa Ishikawa ◽  
Satoshi Amano ◽  
Koichi Nakayama
Keyword(s):  
Nitric Oxide ◽  
Insulin Secretion ◽  
Kinase Inhibitor ◽  
Soluble Guanylate Cyclase ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Dual Effect ◽  
Independent Manner ◽  
No Donor ◽  
Isolated Rat

In isolated rat pancreatic β-cells, the nitric oxide (NO) donor NOC-7 at 1 μM reduced the amplitude of the oscillations of cytosolic Ca2+ concentration ([Ca2+]c) induced by 11.1 mM glucose, and at 10 μM terminated them. In the presence of N G-nitro-l-arginine (l-NNA), however, NOC-7 at 0.5 and 1 μM increased the amplitude of the [Ca2+]c oscillations, although the NO donor at 10 μM still suppressed them. Aqueous NO solution also had a dual effect on the [Ca2+]c oscillations. The soluble guanylate cyclase inhibitor LY-83583 and the cGMP-dependent protein kinase inhibitor KT5823 inhibited the stimulatory effect of NO, and 8-bromo-cGMP increased the amplitude of the [Ca2+]c oscillations. Patch-clamp analyses in the perforated configuration showed that 8-bromo-cGMP inhibited whole cell ATP-sensitive K+ currents in the isolated rat pancreatic β-cells, suggesting that the inhibition by cGMP of ATP-sensitive K+ channels is, at least in part, responsible for the stimulatory effect of NO on the [Ca2+]c oscillations. In the presence ofl-NNA, the glucose-induced insulin secretion from isolated islets was facilitated by 0.5 μM NOC-7, whereas it was suppressed by 10 μM NOC-7. These results suggest that NO facilitates glucose-induced [Ca2+]c oscillations of β-cells and insulin secretion at low concentrations, which effects are mediated by cGMP, whereas NO inhibits them in a cGMP-independent manner at high concentrations.

scholarly journals STAT5 activation by human GH protects insulin-producing cells against interleukin-1β, interferon-γ and tumour necrosis factor-α-induced apoptosis independent of nitric oxide production

2005 ◽  
Vol 187 (1) ◽  
pp. 25-36 ◽  
Author(s):  
Janne Jensen ◽  
Elisabeth D Galsgaard ◽  
Allan E Karlsen ◽  
Ying C Lee ◽  
Jens H Nielsen
Keyword(s):  
Nitric Oxide ◽  
Tumour Necrosis ◽  
Interferon Γ ◽  
Tumour Necrosis Factor Α ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Tnf Α ◽  
Ifn Γ ◽  
Factor Α ◽  
Necrosis Factor

The proinflammatory cytokines interleukin-1β (IL-1β), interferon-γ (IFN-γ) and tumour necrosis factor-α (TNF-α) are toxic to pancreatic β-cells and are implicated in the pathogenesis of type 1 diabetes. We have previously found that GH and prolactin (PRL) stimulate both proliferation and insulin production in pancreatic β-cells and rat insulin-producing INS-1 cells. Here we report that human (h) GH can prevent the apoptotic effects of IL-1β, IFN-γ and TNF-α in INS-1 and INS-1E cells. Using adenovirus-mediated gene transfer, we found that the anti-apoptotic effect of hGH is abrogated by expression of a dominant negative signal transducer and activator of transcription (STAT5) mutant in INS-1E cells. hGH and the cytotoxic cytokines was found to additively increase suppressor of cytokine signalling-3 mRNA expression after 4 h of exposure. In order to identify possible targets for the STAT5-mediated protection of INS-1E cells, we studied the effect of hGH on activation of the transcription factors STAT1 and nuclear factor-κB (NF-κB) by IFN-γ and IL-1β+TNF-α respectively. Gel retardation experiments showed that hGH affects neither IFN-γ+ TNF-α-induced STAT1 DNA binding nor IL-1β and IFN-γ+TNF-α-induced NFκB DNA binding. The lack of influence of hGH on cytokine-mediated activation of STAT1 and NFκB is in accordance with the finding that hGH had only a minor effect on cytokine-induced inducible nitric oxide synthase (iNOS) gene expression and in fact augmented the IL-1β-stimulated nitric oxide production. As the anti-apoptotic Bcl-xL gene has been shown to harbour a STAT5-binding element we measured the expression of Bcl-xL as well as the pro-apoptotic Bax. We found that hGH increased the Bcl-xL/Bax ratio both in the absence and in the presence of cytotoxic cytokines. In conclusion, these results suggested that GH and PRL protect β-cells against cytotoxic cytokines via STAT5-dependent mechanisms distal to iNOS activation possibly at the level of Bcl-xL.

scholarly journals HSP70 Induction by ING Proteins Sensitizes Cells to Tumor Necrosis Factor Alpha Receptor-Mediated Apoptosis

2006 ◽  
Vol 26 (24) ◽  
pp. 9244-9255 ◽  
Author(s):  
Xiaolan Feng ◽  
Shirin Bonni ◽  
Karl Riabowol
Keyword(s):  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Kinase Inhibitor ◽  
Heat Shock Gene ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Primary Fibroblasts ◽  
Factor Alpha ◽  
Necrosis Factor

ABSTRACT ING proteins affect apoptosis, growth, and DNA repair by transducing stress signals such as DNA damage, binding histones, and subsequently regulating chromatin structure and p53 activity. p53 target genes, including the p21 cyclin-dependent kinase inhibitor and Bax, an inducer of apoptosis, are regulated by ING proteins. To identify additional targets downstream of p33ING1 and p32ING2, cDNA microarrays were performed on phenotypically normal human primary fibroblasts. The 0.36% of genes affected by ING proteins in primary fibroblasts were distinct from targets seen in established cells and included the HSP70 heat shock gene, whose promoter was specifically induced >10-fold. ING1-induced expression of HSP70 shifted cells from survival to a death pathway in response to tumor necrosis factor alpha (TNF-α), and p33ING1b protein showed synergy with TNF-α in inducing apoptosis, which correlated with reduced NF-κB-dependent transcription. These findings are consistent with previous reports that HSP70 promotes TNF-α-mediated apoptosis by binding I-κΒ kinase gamma and impairing NF-κB survival signaling. Induction of HSP70 required the amino terminus of ING1b but not the plant homeodomain region that was recently identified as a histone binding domain. Regulation of HSP70 gene expression by the ING tumor suppressors provides a novel link between the INGs and the stress-regulated NF-κB survival pathway important in hypoxia and angiogenesis.

Tumor necrosis factor alpha signaling pathway and apoptosis in pancreatic β cells

Metabolism ◽  
1999 ◽  
Vol 48 (12) ◽  
pp. 1485-1492 ◽  
Author(s):  
Nobuko Ishizuka ◽  
Kazuo Yagui ◽  
Yoshiharu Tokuyama ◽  
Katsumi Yamada ◽  
Yoshifumi Suzuki ◽  
...  
Keyword(s):  
Tumor Necrosis Factor ◽  
Signaling Pathway ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
Necrosis Factor

PPARγ is not required for the inhibitory actions of PGJ2 on cytokine signaling in pancreatic β-cells

2004 ◽  
Vol 286 (3) ◽  
pp. E329-E336 ◽  
Author(s):  
Sarah M. Weber ◽  
Anna L. Scarim ◽  
John A. Corbett
Keyword(s):  
Gene Expression ◽  
Nitric Oxide ◽  
Cytokine Signaling ◽  
Rinm5f Cells ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Inos Gene ◽  
Ifn Γ ◽  
Anti Inflammatory ◽  
Inos Gene Expression

Peroxisome proliferator-activated receptor (PPAR)γ agonists, such as 15-deoxy-Δ12,14-prostaglandin J2 (PGJ2) and troglitazone, have been shown to elicit anti-inflammatory effects in pancreatic β-cells that include inhibition of cytokine-stimulated inducible nitric oxide synthase (iNOS) gene expression and production of nitric oxide. In addition, these ligands impair IL-1-induced NF-κB and MAPK as well as IFN-γ-stimulated signal transducer and activator of transcription (STAT)1 activation in β-cells. The purpose of this study was to determine if PPARγ activation participates in the anti-inflammatory actions of PGJ2 in β-cells. Pretreatment of RINm5F cells for 6 h with PGJ2 results in inhibition of IL-1-stimulated IκB degradation and IFN-γ-stimulated STAT1 phosphorylation. Overexpression of a dominant-negative (dn) PPARγ mutant or treatment with the PPARγ antagonist GW-9662 does not modulate the inhibitory actions of PGJ2 on cytokine signaling in RINm5F cells. Although these agents fail to attenuate the inhibitory actions of PGJ2 on cytokine signaling, they do inhibit PGJ2-stimulated PPARγ response element reporter activity. Consistent with the inability to attenuate the inhibitory actions of PGJ2 on cytokine signaling, neither dnPPARγ nor GW-9662 prevents the inhibitory actions of PGJ2 on IL-1-stimulated iNOS gene expression or nitric oxide production by RINm5F cells. These findings support a PPARγ-independent mechanism by which PPARγ ligands impair cytokine signaling and iNOS expression by islets.

Oxymatrine inhibits lipopolysaccharide-induced inflammation by down-regulating Toll-like receptor 4/nuclear factor-kappa B in macrophages

2015 ◽  
Vol 93 (4) ◽  
pp. 253-260 ◽  
Author(s):  
Yu Zhang ◽  
Ruhong Yan ◽  
Yae Hu
Keyword(s):  
Nitric Oxide ◽  
Interleukin 1 ◽  
Chinese Herb ◽  
Mrna Levels ◽  
Nuclear Factor ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Anti Inflammatory

Oxymatrine (OMT) is the quinolizidine alkaloid extracted from the Chinese herb Sophora flavescens Ait. that has many pharmacological effects and is used for the treatment of some inflammatory diseases. In this study, RAW264.7 cells and THP-1 differentiated macrophages were pretreated with various concentrations of OMT at 2 h prior to treatment with lipopolysaccharide (LPS) (1.0 μg/mL) for different durations. We detected the anti-inflammatory effect of OMT in LPS-stimulated macrophages and investigated the molecular mechanism. We showed that OMT pretreatment significantly inhibited the LPS-induced secretion of nitric oxide (NO), interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) in supernatant, attenuated the mRNA levels of inducible nitric oxide synthase (iNOS), IL-1β, TNF-α, and Toll-like receptor 4 (TLR4), increased TLR4 and phosphorylation of inhibitor of kappa B-alpha (p-IBα) in cytosol, and decreased the nuclear level of nuclear factor-κB (NF-κB) p65 in macrophages. In conclusion, OMT exerts anti-inflammatory properties in LPS-stimulated macrophages by down-regulating the TLR4/NF-κB pathway.

scholarly journals Effects of Shugan-Jianpi Recipe on the Expression of the p38 MAPK/NF-κB Signaling Pathway in the Hepatocytes of NAFLD Rats

Medicines ◽  
2018 ◽  
Vol 5 (3) ◽  
pp. 106 ◽  
Author(s):  
Yuanjun Deng ◽  
Kairui Tang ◽  
Runsen Chen ◽  
Yajie Liu ◽  
Huan Nie ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
P38 Mapk ◽  
Low Dose ◽  
Serum Levels ◽  
Inflammatory Factors ◽  
Enzyme Linked Immunosorbent Assay ◽  
High Dose ◽  
Model Group ◽  
Necrosis Factor Alpha ◽  
Tnf Α

Background: In traditional Chinese medicine, the Shugan-Jianpi recipe is often used in the treatment of nonalcoholic fatty liver disease (NAFLD). This study aimed to explore the mechanism of the Shugan-Jianpi recipe in relation to rats with NAFLD induced by a high-fat diet. Methods: Rats were randomly divided into eight groups: normal group (NG), model group (MG), low-dose Chaihu–Shugan–San group (L-CG), high-dose Chaihu–Shugan–San group (H-CG), low-dose Shenling–Baizhu–San group (L-SG), high-dose Shenling–Baizhu–San group (H-SG), low dose of integrated-recipes group (L-IG), and high dose of integrated-recipes group (H-IG). After 26 weeks, a lipid profile, aspartate, and alanine aminotransferases in serum were detected. The serum levels of inflammatory factors including interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) were analyzed using the enzyme linked immunosorbent assay (ELISA) method. Hepatic pathological changes were observed with hematoxylin-eosin (HE) and oil red O staining. The expression of the p38 mitogen-activated protein kinases (MAPK)/nuclear factor-κB (NF-κB) pathway was detected by quantitative real-time PCR and Western blotting. Results: A pathological section revealed that NAFLD rats have been successfully reproduced. Compared with the model group, each treatment group had different degrees of improvement. The Shugan-Jianpi recipe can inhibit the serum levels of IL-1β, IL-6, and TNF-α in NAFLD rats. The expression of mRNA and a protein related to the p38 MAPK/NF-κB signaling pathway were markedly decreased as a result of the Shugan-Jianpi recipe. Conclusions: The Shugan-Jianpi recipe could attenuate NAFLD progression, and its mechanism may be related to the suppression of the p38 MAPK/NF-κB signaling pathway in hepatocytes.

Sign in / Sign up

Export Citation Format

Share Document