Frank Burr Mallory's landmark observation in 1911 on the histopathology of alcoholic liver disease (ALD) was the first identification of a link between inflammation and ALD. In this review, we ...summarize recent advances regarding the origins and roles of various inflammatory components in ALD. Metabolism of ethanol generates a number of metabolites, including acetate, reactive oxygen species, acetaldehyde, and epigenetic changes, that can induce inflammatory responses. Alcohol and its metabolites can also initiate and aggravate inflammatory conditions by promoting gut leakiness of microbial products, by sensitizing immune cells to stimulation, and by activating innate immune pathways, such as complement. Chronic alcohol consumption also sensitizes nonimmune cells, e.g., hepatocytes, to inflammatory signals and impairs their ability to respond to protective signals. Based on these advances, a number of inflammatory targets have been identified with potential for therapeutic intervention in ALD, presenting new opportunities and challenges for translational research.
Chronic inflammation is often associated with alcoholrelated medical conditions. The key inducer of such inflammation, and also the best understood, is gut microflora-derived lipopolysaccharide ...(LPS). Alcohol can significantly increase the translocation of LPS from the gut. In healthy individuals, the adverse effects of LPS are kept in check by the actions and interactions of multiple organs. The liver plays a central role in detoxifying LPS and producing a balanced cytokine milieu. The central nervous syst...
Background:Refractory pulmonary edema is an infrequent but serious complication in patients receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) for myocardial failure. Left atrial ...(LA) decompression in this setting is important. Although a few methods have been reported, the experience is mostly limited to children. We aimed to evaluate the feasibility of Inoue balloon catheter in percutaneous trans-septal LA decompression in adult cardiogenic patients.Methods and Results:We retrospectively analyzed 16 procedures of trans-septal LA decompression by Inoue balloon catheter in 15 VA-ECMO patients (aged 22–65 years, 6 men) with refractory pulmonary edema from May 2012 to December 2014. Mean left ventricular ejection fraction was 15%. The cause of cardiogenic shock included 7 cases of ischemic heart disease, 1 of dilated cardiomyopathy, 5 of myocarditis, and 2 of fatal ventricular arrhythmia.The procedures were performed 4.3 days after ECMO. Inoue balloon size was 24–27 mm. LA septostomy were successfully created in 14 patients. Procedure time on average was 36.8 min (range, 15–85 min). There were no procedure-related complications.Radiography on the next day showed rapid resolution of pulmonary edema.Conclusions:Trans-septal LA decompression by Inoue balloon catheter is a feasible alternative method for adult patients with refractory pulmonary edema under ECMO.
Interleukin-1 receptor-associated kinase-1 (IRAK-1) is critical for mediating toll-like receptor and interleukin-1 receptor signaling. In this study, we have examined whether IRAK-1 expression is ...altered in high glucose (HG)-stimulated human aortic endothelial cells (HAECs), and whether microRNAs (miRs) target IRAK-1 to regulate HG-induced endothelial inflammation.
HAECs were treated with HG for 24 and 48 h. Real-time PCR, Western blot, monocyte adhesion assay, bioinformatics analysis, TaqMan® arrays, microRNA mimic or inhibitor transfection, luciferase reporter assay and siRNA IRAK-1 transfection were performed. The aortic tissues from db/db type 2 diabetic mice were examined by immunohistochemistry staining.
HG time-dependently increased IRAK-1 mRNA and protein levels in HAECs, and was associated with increased VCAM-1/ICAM-1 gene expression and monocyte adhesion. Bioinformatic analysis, TaqMan® arrays, and real-time PCR were used to confirm that miR-146a-5p, miR-339-5p, and miR-874-3p were significantly downregulated in HG-stimulated HAECs, suggesting impaired feedback restraints on HG-induced endothelial inflammation via IRAK-1. However, only miR-146a-5p mimic transfection reduced the HG-induced upregulation of IRAK-1 expression, VCAM-1/ICAM-1 expression, and monocyte adhesion. Additionally, IRAK-1 depletion reduced HG-induced VCAM-1/ICAM-1 gene expression, and monocyte adhesion, indicating that HG-induced endothelial inflammation was mediated partially through IRAK-1.
, intravenous injections of miR-146a-5p mimic prevented endothelial IRAK-1 and ICAM-1 expression in db/db mice.
These results suggest that miR-146a-5p is involved in the regulation of HG-induced endothelial inflammation via modulation of IRAK-1; indicating that miR-146a-5p may be a novel target for the treatment of diabetic vascular complications.
Background and Aims:
Increased
O
-GlcNAc transferase (OGT)–induced O-linked
N
-acetylglucosamine (
O
-GlcNAc) post-translational modification is linked with diabetic complications. MicroRNA-146a-5p ...(miR-146a-5p) is a negative inflammatory regulator and is downregulated in diabetes. Here, we investigated the interaction between miR-146a-5p and OGT.
Methods:
Human aortic endothelial cells (HAECs) were stimulated with high glucose (25 mM) and glucosamine (25 mM) for 24 h. Western blot, real time PCR, bioinformatics analysis, luciferase reporter assay, miR-146a-5p mimic/inhibitor transfection, siRNA OGT transfection, miR-200a/200b mimic transfection, and OGT pharmacological inhibition (ST045849) were performed. The aorta from miR-146a-5p mimic-treated db/db mice were examined by immunohistochemistry staining.
Results:
HG and glucosamine upregulated OGT mRNA and protein expression, protein
O
-GlcNAcylation, and IL-6 mRNA and protein expression. Real time PCR analysis found that miR-146a-5p was decreased in HG- and glucosamine-stimulated HAECs. This suggested that OGT-induced protein O-GlcNAcylation as a mechanism to downregulate miR-146a-5p. Bioinformatic miR target analysis excluded miR-146a-5p as a post-transcriptional regulator of OGT. However, a luciferase reporter assay confirmed that miR-146a-5p mimic bound to 3′-UTR of human OGT mRNA, indicating that OGT is a non-canonical target of miR-146a-5p. Transfection with miR-146a-5p mimic and inhibitor confirmed that miR-146a-5p regulated OGT/protein O-GlcNAcylation/IL-6 expression levels. Furthermore, OGT siRNA transfection, miR-200a/miR-200b mimic transfection, and ST045849 increased HG-induced miR-146a-5p expression levels, indicating that HG-induced miR-146a-5p downregulation is partially mediated through OGT-mediated protein
O
-GlcNAcylation. In
vivo
, intravenous injections of miR-146a mimic decreased endothelial OGT and IL6 expression in db/db mice.
Conclusion:
A non-canonical positive feedback interaction between miR-146a-5p and OGT is involved in a vicious cycle to aggravate HG-induced vascular complications.
Diabetes is associated with hyperglycemia and increased thrombin production. However, it is unknown whether a combination of high glucose and thrombin can modulate the expression of NAPDH oxidase ...(Nox) subtypes in human aortic endothelial cells (HAECs). Moreover, we investigated the role of a diabetes-associated microRNA (miR-146a) in a diabetic atherothrombosis model. We showed that high glucose (HG) exerted a synergistic effect with thrombin to induce a 10.69-fold increase in Nox4 mRNA level in HAECs. Increased Nox4 mRNA expression was associated with increased Nox4 protein expression and ROS production. Inflammatory cytokine kit identified that the treatment increased IL-8 and IL-6 levels. Moreover, HG/thrombin treatment caused an 11.43-fold increase of THP-1 adhesion to HAECs. In silico analysis identified the homology between miR-146a and the 3′-untranslated region of the Nox4 mRNA, and a luciferase reporter assay confirmed that the miR-146a mimic bound to this Nox4 regulatory region. Additionally, miR-146a expression was decreased to 58% of that in the control, indicating impaired feedback restraint of HG/thrombin-induced endothelial inflammation. In contrast, miR-146a mimic transfection attenuated HG/thrombin-induced upregulation of Nox4 expression, ROS generation, and inflammatory phenotypes. In conclusion, miR-146a is involved in the regulation of endothelial inflammation via modulation of Nox4 expression in a diabetic atherothrombosis model.
Hepatitis C virus infection affects 170 million people worldwide, and the majority of individuals exposed to HCV develop chronic hepatitis leading to progressive liver damage, cirrhosis, and ...hepatocellular cancer. The natural history of HCV infection is influenced by genetic and environmental factors of which chronic alcohol use is an independent risk factor for cirrhosis in HCV‐infected individuals. Both the hepatitis C virus and alcohol damage the liver and result in immune alterations contributing to both decreased viral clearance and liver injury. This review will capture the major components of the interactions between alcohol and HCV infection to provide better understanding for the molecular basis of the dangerous combination of alcohol use and HCV infection. Common targets of HCV and alcohol involve innate immune recognition and dendritic cells, the critical cell type in antigen presentation and antiviral immunity. In addition, both alcohol and HCV affect intracellular processes critical for hepatocyte and immune cell functions including mitochondrial and proteasomal activation. Finally, both chronic alcohol use and hepatitis C virus infection increase the risk of hepatocellular cancer. The common molecular mechanisms underlying the pathological interactions between alcohol and HCV include the modulation of cytokine production, lipopolysaccharide (LPS)‐TLR4 signaling, and reactive oxygen species (ROS) production. LPS‐induced chronic inflammation is not only a major cause of progressive liver injury and fibrosis, but it can also contribute to modification of the tissue environment and stem cells to promote hepatocellular cancer development. Alteration of these processes by alcohol and HCV produces an environment of impaired antiviral immune response, greater hepatocellular injury, and activation of cell proliferation and dedifferentiation.
The angiotensin-converting enzyme 2/angiotensin-(1-7)/Mas axis is a pathway that acts against the detrimental effects of the renin-angiotensin system. However, the effects of angiotensin-(1-7) on ...endothelial protein expression and the related phenotypes are unclear. We performed a duplicate of iTRAQ quantitative proteomic analysis on human aortic endothelial cells (HAECs) treated with angiotensin-(1-7) for 6 hours. Cofilin-1 was identified as a highly abundant candidate with consistent >30% coverage and >1.2-fold overexpression in the angiotensin-(1-7)-treated group. Gene ontology analysis showed that the "regulation_of_mitosis" was significantly altered, and cell cycle analysis indicated that the 6-hour angiotensin-(1-7) treatment significantly induced G0/G1 arrest. Knockdown of the cofilin-1 (CFL1) gene suggested the G0/G1 phase arrest was mediated by the modulation of p27 and the p21/Cyclin/CDK complex by Cofilin-1. Interestingly, quiescent HAECs escaped G0/G1 arrest upon angiotensin-(1-7) treatment for 24 hours, and angiotensin-(1-7) induced autophagy by upregulating Beclin-1 and microtubule-associated protein 1 light chain 3b-II expression, which was also attenuated by A779 pre-treatment and CFL1 knockdown. After pre-treatment with 3-methyladenine (3MA), treatment with angiotensin-(1-7) for 24 h induced significant G0/G1 phase arrest and apoptosis, suggesting a pro-survival role of autophagy in this context. In conclusion, Cofilin-1 plays a dominant role in angiotensin-(1-7)-induced G0/G1 arrest and autophagy to maintain cellular homeostasis in HAECs.
The angiotensin-(1-7)/angiotensin-converting enzyme 2/Mas receptor axis counter-regulates the detrimental effects of angiotensin II. Beneficial effects of angiotensin-(1-7), including ...anti-inflammation, oxidative stress reduction, and anti-thrombosis, have been reported. Previous studies documented that ramipril decreased thrombin generation in human hypertension and that the anti-thrombotic effects of captopril and losartan were angiotensin-(1-7)-dependent, suggesting an interaction between thrombin and angiotensin-(1-7). However, it is not clear whether angiotensin-(1-7) can alleviate the endothelial phenotypic changes induced by thrombin. We have previously documented cytoskeleton remodeling, cell adhesion, and cell migration as dominant altered phenotypes in thrombin-stimulated human aortic endothelial cells (HAECs). In this study, we investigated whether angiotensin-(1-7) can modulate thrombin-induced phenotypic changes. Furthermore, we investigated whether NAPDH oxidase 5 (Nox5)-produced reactive oxygen species (ROS) play a significant role in angiotensin-(1-7)-mediated phenotypic changes.
HAECs were pretreated with 100 nM angiotensin-(1-7) for 1 h, followed by stimulation with 2 units/mL thrombin for different times. Immunofluorescent assay, monocyte adhesion assay, wound-healing assay, ROS assay, real-time PCR, Western blotting, and Nox5 siRNA transfection were conducted. HAECs were pretreated with the ROS scavenger N-acetylcysteine (NAC) to determine whether thrombin-induced phenotypic changes depended on ROS production.
Angiotensin-(1-7) prevented thrombin-induced actin cytoskeleton derangements, monocyte adhesion, and migratory impairment. Nox5 siRNA transfection confirmed that thrombin-induced Nox5 expression stimulated ROS production and increased HO-1/NQO-1/ICAM-1/VCAM-1 gene expression, all of which were decreased by angiotensin-(1-7). Phenotypic changes induced by thrombin were prevented by NAC pretreatment.
Angiotensin-(1-7) prevents actin cytoskeleton derangement, monocyte adhesion, and migration impairment induced by thrombin via downregulation of ROS production. In addition, thrombin-induced Nox5 expression is involved in the production of ROS, and angiotensin-(1-7) decreases ROS through its inhibitory effect on Nox5 expression.
Increased
-linked
-acetylglucosamine (
-GlcNAc) modification of proteins by
-GlcNAc transferase (OGT) is associated with diabetic complications. Furthermore, oxidative stress promotes endothelial ...inflammation during diabetes. A previous study reported that microRNA-200 (miR-200) family members are sensitive to oxidative stress. In this study, we examined whether miR-200a and miR-200b regulate high-glucose (HG)-induced OGT expression in human aortic endothelial cells (HAECs) and whether miRNA-200a/200b downregulate OGT expression to control HG-induced endothelial inflammation.
HAECs were stimulated with high glucose (25 mM) for 12 and 24 h. Real-time polymerase chain reaction (PCR), western blotting, THP-1 adhesion assay, bioinformatics predication, transfection of miR-200a/200b mimic or inhibitor, luciferase reporter assay, and transfection of siRNA OGT were performed. The aortic endothelium of db/db diabetic mice was evaluated by immunohistochemistry staining.
HG upregulated OGT mRNA and protein expression and protein
-GlcNAcylation levels (RL2 antibody) in HAECs, and showed increased intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin gene expression; ICAM-1 expression; and THP-1 adhesion. Bioinformatics analysis revealed homologous sequences between members of the miR-200 family and the 3'-untranslated region (3'-UTR) of OGT mRNA, and real-time PCR analysis confirmed that members of miR-200 family were significantly decreased in HG-stimulated HAECs. This suggests the presence of an impaired feedback restraint on HG-induced endothelial protein
-GlcNAcylation levels because of OGT upregulation. A luciferase reporter assay demonstrated that miR-200a/200b mimics bind to the 3'-UTR of OGT mRNA. Transfection with miR-200a/200b mimics significantly inhibited HG-induced OGT mRNA expression, OGT protein expression; protein
-GlcNAcylation levels; ICAM-1, VCAM-1, and E-selectin gene expression; ICAM-1 expression; and THP-1 adhesion. Additionally, siRNA-mediated OGT depletion reduced HG-induced protein
-GlcNAcylation; ICAM-1, VCAM-1, and E-selectin gene expression; ICAM-1 expression; and THP-1 adhesion, confirming that HG-induced endothelial inflammation is partially mediated via OGT-induced protein
-GlcNAcylation. These results were validated
: tail-vein injection of miR-200a/200b mimics downregulated endothelial OGT and ICAM-1 expression in db/db mice.
miR-200a/200b are involved in modulating HG-induced endothelial inflammation by regulating OGT-mediated protein
-GlcNAcylation, suggesting the therapeutic role of miR-200a/200b on vascular complications in diabetes.
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