scholarly journals Neutrophil Extracellular Traps Promote the Development of Intracranial Aneurysm Rupture

Hypertension ◽  
2021 ◽  
Author(s):  
Masaaki Korai ◽  
James Purcell ◽  
Yoshinobu Kamio ◽  
Kazuha Mitsui ◽  
Hajime Furukawa ◽  
...  
Keyword(s):  
Intracranial Aneurysm ◽  
Interleukin 1 ◽  
Neutrophil Extracellular Traps ◽  
Aneurysm Rupture ◽  
Arginine Deiminase ◽  
Intercellular Adhesion Molecule ◽  
Necrosis Factor Alpha ◽  
Extracellular Traps ◽  
Peptidyl Arginine Deiminase ◽  
Aneurysm Wall

Potential roles for neutrophils in the pathophysiology of intracranial aneurysm have long been suggested by clinical observations. The presence of neutrophil enzymes in the aneurysm wall has been associated with significant increases in rupture risk. However, the mechanisms by which neutrophils may promote aneurysm rupture are not well understood. Neutrophil extracellular traps (NETs) were implicated in many diseases that involve inflammation and tissue remodeling, including atherosclerosis, vasculitis, and abdominal aortic aneurysm. Therefore, we hypothesized that NETs may promote the rupture of intracranial aneurysm, and that removal of NETs can reduce the rate of rupture. We employed both pharmacological and genetic approaches for the disruption of NETs and used a mouse model of intracranial aneurysm to investigate the roles of NETs in the development of intracranial aneurysm rupture. Here, we showed that NETs are detected in human intracranial aneurysms. Both global and granulocyte-specific knockout of peptidyl arginine deiminase 4 (an enzyme essential for NET formation) reduced the rate of aneurysm rupture. Pharmacological blockade of the NET formation by Cl-amidine also reduced the rate of aneurysm rupture. In addition, the resolution of already formed NETs by deoxyribonuclease was effective against aneurysm rupture. Inhibition of NETs formation with Cl-amidine decreased mRNA expression of proinflammatory cytokines (intercellular adhesion molecule 1 (ICAM-1), interleukin 1 beta (IL-1β), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor alpha (TNF-α)) in cerebral arteries. These data suggest that NETs promote the rupture of intracranial aneurysm. Pharmacological removal of NETs, by inhibition of peptidyl arginine deiminase 4 or resolution of already-formed NETs, may represent a potential therapeutic strategy for preventing aneurysmal rupture.

scholarly journals Silver Nanoparticles Induce Neutrophil Extracellular Traps Via Activation of PAD and Neutrophil Elastase

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 317
Author(s):  
HanGoo Kang ◽  
Jinwon Seo ◽  
Eun-Jeong Yang ◽  
In-Hong Choi
Keyword(s):  
Silver Nanoparticles ◽  
Neutrophil Elastase ◽  
Mammalian Cells ◽  
Antimicrobial Properties ◽  
Neutrophil Extracellular Traps ◽  
Arginine Deiminase ◽  
Human Neutrophils ◽  
Extracellular Traps ◽  
Peptidyl Arginine Deiminase ◽  
Key Factor

Silver nanoparticles (AgNPs) are widely used in various fields because of their antimicrobial properties. However, many studies have reported that AgNPs can be harmful to both microorganisms and humans. Reactive oxygen species (ROS) are a key factor of cytotoxicity of AgNPs in mammalian cells and an important factor in the immune reaction of neutrophils. The immune reactions of neutrophils include the expulsion of webs of DNA surrounded by histones and granular proteins. These webs of DNA are termed neutrophil extracellular traps (NETs). NETs allow neutrophils to catch and destroy pathogens in extracellular spaces. In this study, we investigated how AgNPs stimulate neutrophils, specifically focusing on NETs. Freshly isolated human neutrophils were treated with 5 or 100 nm AgNPs. The 5 nm AgNPs induced NET formation, but the 100 nm AgNPs did not. Subsequently, we investigated the mechanism of AgNP-induced NETs using known inhibitors related to NET formation. AgNP-induced NETs were dependent on ROS, peptidyl arginine deiminase, and neutrophil elastase. The result in this study indicates that treatment of 5 nm AgNPs induce NET formation through histone citrullination by peptidyl arginine deiminase and histone cleavage by neutrophil elastase.

Abstract 147: Role of Nicotine in the Development of Intracranial Aneurysm Rupture

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Yoshinobu Kamio ◽  
Hajime Furukawa ◽  
Kimihiko Yokosuka ◽  
Masaaki Korai ◽  
Kazuha Mitsui ◽  
...  
Keyword(s):  
Intracranial Aneurysm ◽  
Tobacco Smoke ◽  
Intracranial Aneurysms ◽  
Aneurysm Rupture ◽  
Alpha7 Nicotinic Acetylcholine Receptor ◽  
Acetate Salt ◽  
Nicotine Receptors ◽  
Aneurysm Wall ◽  
Salt Hypertension

Background: Nicotine is one of main chemicals of tobacco smoke and promotes atherosclerosis and stroke. Tobacco smoke is considered an independent risk factor for intracranial aneurysm formation, growth, and rupture. There are mainly 5 subtypes of nicotine receptors. Roles of alpha7 nicotinic acetylcholine receptor (α7nAChR) in inflammation and vascular remodeling are diverse and context-dependent. Notably, endothelial α7nAChR is considered to mediate nicotine-induced inflammation. Activation of endothelial α7nAChR by nicotine may promote aneurysm rupture by increasing the aneurysm wall inflammation. Using a mouse model of intracranial aneurysm, we examined effects of nicotine in aneurysm rupture. Moreover we investigated potential roles of α7nAChR stimulation by nicotine in the pathophysiology of intracranial aneurysms. Methods: Intracranial aneurysms were induced by a combination of elastase injection into the cerebrospinal fluid and deoxycorticosteron acetate-salt (DOCA-salt) hypertension in male mice. Mice were treated with (1) nicotine (5 mg/kg/day, n=25); (2) saline sc (n=22) for three weeks after aneurysm induction. To investigate the effect of α7nAChR, mice were treated with (1) saline sc + saline ip (n=11); (2) saline sc + α7nAChR antagonist (Methyllycaconitine, MLA 5mg/kg/day) ip (n=13); (3) nicotine (5 mg/kg/day, sc, 28 days) + saline ip (n=18); (4) nicotine sc + MLA ip (n=18). Results: Nicotine alone significantly increased aneurysmal rupture compared with saline treatment (89% vs 46%, p=0.009). While α7nAChR antagonist did not affect the incidence of aneurysm or rupture rates, the α7nAChR antagonist significantly reduced the deleterious effect of nicotine as indicated by the reduction of the rupture rates (41% vs 100%: nicotine sc + MLA ip group vs nicotine sc + saline ip group, p=0.027). Conclusion: Our data indicate the promotion of aneurysm rupture by nicotine may be mediated by its stimulation of alpha7nAChR.

Induction of ICAM-1 by TNF-alpha, IL-1 beta, and LPS in human endothelial cells after downregulation of PKC

1992 ◽  
Vol 263 (4) ◽  
pp. C767-C772 ◽  
Author(s):  
C. L. Myers ◽  
S. J. Wertheimer ◽  
J. Schembri-King ◽  
T. Parks ◽  
R. W. Wallace
Keyword(s):  
Endothelial Cells ◽  
Protein Kinase ◽  
Umbilical Vein ◽  
Interleukin 1 ◽  
Protein Kinase Inhibitors ◽  
Intercellular Adhesion Molecule ◽  
Tnf Alpha ◽  
Necrosis Factor Alpha ◽  
Western Blots ◽  
Mrna Induction

The intercellular adhesion molecule 1 (ICAM-1) is induced on endothelial cells by tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and lipopolysaccharide (LPS). We have reported the sensitivity of cytokine-induced ICAM-1 expression to protein kinase inhibitors, including inhibitors of protein kinase C (PKC) [C. L. Myers, S. N. Desai, J. Schembri-King, G. L. Letts, and R. W. Wallace. Am. J. Physiol. 262 (Cell Physiol. 31): C365-C373, 1992]. To directly investigate the role of PKC in ICAM-1 induction, we downregulated PKC by pretreatment of human umbilical vein endothelial cells with phorbol 12-myristate 13-acetate (PMA) and assessed ICAM-1 protein and mRNA induction elicited by subsequent exposure to inflammatory stimuli. PMA treatment results in ICAM-1 protein induction that declines to basal levels by 3 days. Western blots of endothelial cell lysates reveal a nearly complete loss of immunologically reactive PKC. Subsequent activation with cytokine or LPS leads to reinduction of ICAM-1 protein and mRNA; however, the cells no longer produced substantial amounts of ICAM-1 protein or mRNA in response to PMA stimulation. Cross desensitization is observed with phorbol dibutyrate, while 4 alpha-phorbol has no desensitizing effect. The data indicate that PKC activation, while capable of inducing ICAM-1 expression, is not essential for ICAM-1 induction by the inflammatory mediators TNF-alpha, IL-1 beta, or LPS.

scholarly journals Biochemical Evaluation of the Antioxidant Effects of Hydroxytyrosol on Pancreatitis-Associated Gut Injury

Antioxidants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 781 ◽  
Author(s):  
Roberta Fusco ◽  
Marika Cordaro ◽  
Rosalba Siracusa ◽  
Ramona D’Amico ◽  
Tiziana Genovese ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Interleukin 1 ◽  
Antioxidant Properties ◽  
Pancreatic Tissue ◽  
Intercellular Adhesion Molecule ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Intercellular Adhesion Molecule 1 ◽  
Colon Tissue ◽  
Necrosis Factor Alpha

Acute pancreatitis is a severe abdominal pathology often associated with several complications including gut dysfunction. Oxidative stress is one of the most important pathways involved in this pathology. Hydroxytyrosol (HT), a phenolic compound obtained from olive oil, has shown anti-inflammatory and antioxidant properties. We evaluated the effects of HT administration on pancreatic and intestinal injury induced by caerulein administration. CD1 female mice were administered caerulein (50 μg/kg) for 10 h. HT treatment (5 mg/kg) was performed 30 min after the first caerulein injection and for two consecutive hours afterwards. One hour after the last caerulein injection, mice were sacrificed and serum, colon and pancreatic tissue samples were collected. HT was able to reduce the serum hallmarks of pancreatitis (amylase and lipase), histological damage score in both pancreas and colon tissue, inflammatory cells recruitment (mast cells) in both injured tissues, intrapancreatic trypsin activity and overexpression of the adhesion molecules (Intercellular Adhesion Molecule-1 (ICAM-1) and P-selectin) in colon. Additionally, HT reduced cytokine (interleukin 1 beta (IL- 1β), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α)) levels in serum, pancreas and colon tissue and chemokine release (monocyte chemotactic protein-1 (MCP1/CCL2)) in pancreas and colon tissue. HT decreased lipid peroxidation and oxidative stress (superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) activity) by enhancing the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) in both injured tissues. Moreover, HT preserved intestinal barrier integrity, as shown by the diamine oxidase (DAO) serum levels and tight junction (zonula occludens (ZO) and occludin) expression in pancreas and colon. Our findings demonstrated that HT would be an important therapeutic tool against pancreatitis-induced injuries in the pancreas and gut.

scholarly journals Systematic review and meta-analysis of the associations of vegan and vegetarian diets with inflammatory biomarkers

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Juliane Menzel ◽  
Afraa Jabakhanji ◽  
Ronald Biemann ◽  
Knut Mai ◽  
Klaus Abraham ◽  
...  
Keyword(s):  
Systematic Review ◽  
Meta Analysis ◽  
Interleukin 1 ◽  
Mean Difference ◽  
Inflammatory Biomarkers ◽  
Vegan Diet ◽  
Intercellular Adhesion Molecule ◽  
Intercellular Adhesion Molecule 1 ◽  
Necrosis Factor Alpha ◽  
Cross Sectional

AbstractPlant-based diets like vegetarian or vegan diets might influence circulating levels of inflammatory biomarkers, thereby reducing the risk of chronic diseases. This systematic review and meta-analysis aimed to investigate the associations of veganism and vegetarianism with circulating inflammatory biomarkers in comparison to omnivores. Literature search was conducted in Pubmed and EMBASE until April 2020 and mean differences of biomarkers were assessed for: C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-18 (IL-18), interleukin-1 receptor antagonist (IL-1 RA), tumor necrosis factor-alpha (TNF-ɑ), E-selectin, intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1), adiponectin, omentin-1 and resistin. Of initially identified 1073 publications, 21 cross-sectional studies met the inclusion criteria and were included in the systematic review and meta-analysis. Vegan diet was associated with lower levels of CRP compared to omnivores [mean difference − 0.54 mg/l, 95%-CI: − 0.79 to − 0.28, p < 0.0001]. This association was less pronounced in vegetarians [mean difference − 0.25 mg/l, 95%-CI: − 0.49 to 0.00, p = 0.05]. In patients with impaired kidney function, the association between vegetarian nutrition and CRP was much stronger with − 3.91 mg/l (95%-CI: − 5.23 to − 2.60; p < 0.0001). No substantial effects were observed for all other inflammatory biomarkers. Despite strong associations between CRP and a vegan or vegetarian diet were seen, further research is needed, as most inflammatory biomarkers were investigated only in single studies so far.

Nuclear Factor κB and Anesthetic Preconditioning during Myocardial Ischemia-Reperfusion

2004 ◽  
Vol 100 (3) ◽  
pp. 540-546 ◽  
Author(s):  
Caiyun Zhong ◽  
Yamei Zhou ◽  
Hong Liu
Keyword(s):  
Ischemia Reperfusion ◽  
Interleukin 1 ◽  
Intercellular Adhesion Molecule ◽  
Nuclear Factor ◽  
Intercellular Adhesion Molecule 1 ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
Nf Kappab ◽  
Myocardial Ischemia Reperfusion ◽  
Oxide Synthase

Background Volatile anesthetic preconditioning (APC) protects against myocardial ischemia-reperfusion (IR) injury, but the precise mechanisms underlying this phenomenon remain undefined. To investigate the molecular mechanism of APC in myocardial protection, the activation of nuclear factor (NF) kappaB and its regulated inflammatory mediators expression were examined in the current study. Methods Hearts from male rats were isolated, Langendorff perfused, and randomly assigned to one of three groups: (1) the control group: hearts were continuously perfused for 130 min; (2) the IR group: 30 min of equilibration, 15 min of baseline, 25 min of ischemia, 60 min of reperfusion; and (3) the APC + IR group: 30 min of equilibration, 10 min of sevoflurane exposure and a 5-min washout, 25 min of global ischemia, 60 min of reperfusion. Tissue samples were acquired at the end of reperfusion. NF-kappaB activity was determined by electrophoretic mobility shift assay. The NF-kappaB inhibitor, IkappaB-alpha, was determined by Western blot analysis. Myocardial inflammatory mediators, including tumor necrosis factor alpha, interleukin 1, intercellular adhesion molecule 1, and inducible nitric oxide synthase, were also assessed by Western blot analysis. Results Nuclear factor kappaB-DNA binding activity was significantly increased at the end of reperfusion in rat myocardium, and cytosolic IkappaB-alpha was decreased. Supershift assay revealed the involvement of NF-kappaB p65 and p50 subunits. APC with sevoflurane attenuated NF-kappaB activation and reduced the expression of tumor necrosis factor alpha, interleukin 1, intercellular adhesion molecule 1, and inducible nitric oxide synthase. APC also reduced infarct size and creatine kinase release and improved myocardial left ventricular developed pressure during IR. Conclusions The results of this study indicate that attenuation of NF-kappaB activation and subsequent down-regulation of NF-kappaB-dependent inflammatory gene expression plays an important role in the protective mechanism of APC against acute myocardial IR injury.

scholarly journals Age-Dependent Levels of Select Immunological Mediators in Sera of Healthy Children

1998 ◽  
Vol 5 (1) ◽  
pp. 28-32 ◽  
Author(s):  
Ulrich Sack ◽  
Ullrich Burkhardt ◽  
Michael Borte ◽  
Hiltrud Schädlich ◽  
Kerstin Berg ◽  
...  
Keyword(s):  
Interleukin 1 ◽  
Physical Growth ◽  
Intercellular Adhesion Molecule ◽  
Healthy Children ◽  
Intercellular Adhesion Molecule 1 ◽  
Necrosis Factor Alpha ◽  
Age Related ◽  
Tnf Α ◽  
Age Dependent ◽  
Ifn Γ

ABSTRACT Serum cytokine levels were measured in 275 healthy children of different ages (3 to 17 years). Interleukin-1 receptor antagonist (IL-1RA), soluble IL-2R (sIL-2R) (sCD25), IL-6, IL-8, tumor necrosis factor alpha (TNF-α), soluble TNF receptor type II (sTNF-RII) (sCD120b), gamma interferon (IFN-γ), soluble intercellular adhesion molecule 1 (sICAM-1) (sCD54), soluble E selectin (sE-selectin) (ELAM-1; sCD62E), sCD14, and neopterin were measured with commercial test kits. The mean levels of IL-1RA, sIL-2R, TNF-α, sICAM-1, sE-selectin, and sCD14 were higher than in healthy adults. In contrast, IFN-γ and IL-8 were hardly detectable in children and thereby significantly lower than in adults. In the case of TNF-α, sICAM-1, sE selectin, and sCD14, there was a high interindividual variability, apparently unrelated to disease. The profiles of some cytokines, i.e., IL-1RA, IL-6, and TNF-α, showed age-related increases that overlapped with known patterns of physical growth. Of note, sIL-2R and sE-selectin instead declined with time. Because of the remarkable age-dependent variability in healthy pediatric subjects, disease-related changes, as well as therapy-dependent alterations, should be considered with caution.

Sign in / Sign up

Export Citation Format

Share Document