Molecular Basis for Down-Regulation of the Inflammatory Responses by Epigallocatechin-3-Gallate in Macrophages

2013 ◽  
pp. 1239-1248
Author(s):  
Eui-Hong Byun ◽  
Hirofumi Tachibana
Keyword(s):  
Molecular Basis ◽  
Inflammatory Responses ◽  
Down Regulation

Inhibitory effects of vasostatin-1 against atherogenesis

2018 ◽  
Vol 132 (23) ◽  
pp. 2493-2507 ◽  
Author(s):  
Yuki Sato ◽  
Rena Watanabe ◽  
Nozomi Uchiyama ◽  
Nana Ozawa ◽  
Yui Takahashi ◽  
...  
Keyword(s):  
Adhesion Molecule ◽  
Inflammatory Responses ◽  
Foam Cell ◽  
Cell Formation ◽  
Density Lipoprotein ◽  
Foam Cell Formation ◽  
Inhibitory Effects ◽  
Macrophage Foam Cell ◽  
Down Regulation ◽  
Atherosclerotic Lesions

Vasostatin-1, a chromogranin A (CgA)-derived peptide (76 amino acids), is known to suppress vasoconstriction and angiogenesis. A recent study has shown that vasostatin-1 suppresses the adhesion of human U937 monocytes to human endothelial cells (HECs) via adhesion molecule down-regulation. The present study evaluated the expression of vasostatin-1 in human atherosclerotic lesions and its effects on inflammatory responses in HECs and human THP-1 monocyte-derived macrophages, macrophage foam cell formation, migration and proliferation of human aortic smooth muscle cells (HASMCs) and extracellular matrix (ECM) production by HASMCs, and atherogenesis in apolipoprotein E-deficient (ApoE−/−) mice. Vasostatin-1 was expressed around Monckeberg’s medial calcific sclerosis in human radial arteries. Vasostatin-1 suppressed lipopolysaccharide (LPS)-induced up-regulation of monocyte chemotactic protein-1 (MCP-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in HECs. Vasostatin-1 suppressed inflammatory M1 phenotype and LPS-induced interleukin-6 (IL-6) secretion via nuclear factor-κB (NF-κB) down-regulation in macrophages. Vasostatin-1 suppressed oxidized low-density lipoprotein (oxLDL)-induced foam cell formation associated with acyl-CoA:cholesterol acyltransferase-1 (ACAT-1) and CD36 down-regulation and ATP-binding cassette transporter A1 (ABCA1) up-regulation in macrophages. In HASMCs, vasostatin-1 suppressed angiotensin II (AngII)-induced migration and collagen-3 and fibronectin expression via decreasing ERK1/2 and p38 phosphorylation, but increased elastin expression and matrix metalloproteinase (MMP)-2 and MMP-9 activities via increasing Akt and JNK phosphorylation. Vasostatin-1 did not affect the proliferation and apoptosis in HASMCs. Four-week infusion of vasostatin-1 suppressed the development of aortic atherosclerotic lesions with reductions in intra-plaque inflammation, macrophage infiltration, and SMC content, and plasma glucose level in ApoE−/− mice. These results indicate the inhibitory effects of vasostatin-1 against atherogenesis. The present study provided the first evidence that vasostatin-1 may serve as a novel therapeutic target for atherosclerosis.

scholarly journals Interferon Regulatory Factor 5 Mediates Lipopolysaccharide-Induced Neuroinflammation

2020 ◽  
Vol 11 ◽  
Author(s):  
Ziqi Fan ◽  
Shuai Zhao ◽  
Yueli Zhu ◽  
Zheyu Li ◽  
Zhirong Liu ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Inflammatory Responses ◽  
Interferon Regulatory Factor ◽  
Microglial Cells ◽  
Regulatory Factor ◽  
Down Regulation ◽  
Interferon Regulatory Factor 5 ◽  
Bv2 Microglial Cells ◽  
Lps Treatment ◽  
Pro Inflammatory Cytokines

BackgroundActivated microglia play a vital role in neuroinflammation in the central nervous system (CNS), which is associated with the pathogenesis and the progression of neurological diseases. Interferon regulatory factor 5 (IRF5) has been well established participating in inflammatory responses and is highly expressed in M1 macrophage in the periphery, the role of which in the CNS remains elusive.MethodsLipopolysaccharide (LPS) was employed to induce neuroinflammation. Down-regulation of IRF5 in C57/BL6 mice and BV2 microglial cells were achieved by IRF5 siRNA transfection. The levels of pro-inflammatory cytokines were evaluated by ELISA and quantitative real-time PCR. The expression levels of IRF5 were examined by immunofluorescence and Western blot.ResultsLPS induced significantly elevated expression of IRF5 in mouse brain, which co-localized with CD11b-positive microglia. Down-regulation of IRF5 quenched the pro-inflammatory responses. The levels of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were up-regulated at 4 h after LPS treatment, which were significantly down-regulated with the knockdown of IRF5. LPS-induced pro-inflammatory responses were transient, which were comparable to control group at 24 h after LPS treatment. However, LPS did not up-regulate the expression of IRF5 in BV2 microglial cells, indicating that LPS-induced inflammation in BV2 cells does not involve IRF5 signaling.ConclusionsIRF5 mediates the inflammatory responses in the CNS, which might serve as a therapeutic target for CNS inflammatory diseases. LPS-induced inflammation does not involve IRF5 signaling in BV2 microglia.

scholarly journals HOXD8/DIAPH2-AS1 epigenetically regulates PAX3 and impairs HTR-8/SVneo cell function under hypoxia

2019 ◽  
Vol 39 (1) ◽  
Author(s):  
Yaling Feng ◽  
Jianxia Wang ◽  
Yue He ◽  
Heng Zhang ◽  
Minhui Jiang ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Rna Interference ◽  
Chromatin Immunoprecipitation ◽  
Regulatory Network ◽  
Molecular Basis ◽  
Promoter Region ◽  
Cell Function ◽  
Down Regulation ◽  
Histone 3 ◽  
Development Data

Abstract The present study aimed to unravel the molecular basis underlying PAX3 down-regulation, known to be involved in pre-eclampsia (PE) occurrence and development. Data obtained from databases suggested that Pax3 methylation levels in the promoter region are high in the placentas of PE patients. However, the expression of methylation-adjusting enzymes, including DNMT1, LSD1, and EZH2, did not change. Since lncRNAs enhance the function of methylation-related enzymes independently of expression, we selected three lncRNAs, RP11-269F21.2, DIAPH2-AS1, and RP11-445K13.2, predicted to interact with methylation-adjusting enzymes. Two transcription factors, HOXD8 and Lhx3, predicted to regulate the expression of lncRNAs, were also selected. Using RNA interference technology, HOXD8 and Lhx3 were found to positively regulate DIAPH2-AS1 and RP11-445K13.2 in HTR-8/SVneo cells. Chromatin immunoprecipitation assays determined that DIAPH2-AS1 recruited LSD1 to histone 3, increasing DNMT1 stability at H3. The HOXD8/DIAPH2-AS1 network regulated HTR-8/SVneo cell function under hypoxia by epigenetically regulating PAX3. This regulatory network may thus be responsible for PAX3 down-regulation in the placentas of PE patients.

scholarly journals The Molecular Basis for the Lack of Inflammatory Responses in Mouse Embryonic Stem Cells and Their Differentiated Cells

2017 ◽  
Vol 198 (5) ◽  
pp. 2147-2155 ◽  
Author(s):  
William D’Angelo ◽  
Chandan Gurung ◽  
Dhiraj Acharya ◽  
Bohan Chen ◽  
Natalya Ortolano ◽  
...  
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Molecular Basis ◽  
Inflammatory Responses ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cells ◽  
Differentiated Cells

scholarly journals Severe Altered Immune Status After Burn Injury Is Associated With Bacterial Infection and Septic Shock

2021 ◽  
Vol 12 ◽  
Author(s):  
Hélène Moins-Teisserenc ◽  
Debora Jorge Cordeiro ◽  
Vincent Audigier ◽  
Quentin Ressaire ◽  
Mourad Benyamina ◽  
...  
Keyword(s):  
Septic Shock ◽  
Innate Immunity ◽  
Bacterial Infection ◽  
Adaptive Immunity ◽  
Bacterial Infections ◽  
Burn Injury ◽  
Inflammatory Responses ◽  
Burn Patients ◽  
Down Regulation ◽  
Risk Of Death

Introduction: Burn injury is associated with a high risk of death. Whether a pattern of immune and inflammatory responses after burn is associated with outcome is unknown. The aim of this study was to explore the association between systemic immune and inflammatory responses and outcome in severely-ill burn patients.Materials and Methods: Innate immunity, adaptive immunity, activation and stress and inflammation biomarkers were collected at admission and days 2, 7, 14, and 28 in severely-ill adult burn patients. Primary endpoint was mortality at day 90, secondary endpoint was secondary infections. Healthy donors (HD) served as controls. Multiple Factorial Analysis (MFA) was used to identify patterns of immune response.Results: 50 patients were included. Age was 49.2 (44.2–54.2) years, total burn body surface area was 38.0% (32.7–43.3). Burn injury showed an upregulation of adaptive immunity and activation biomarkers and a down regulation of innate immunity and stress/inflammation biomarkers. High interleukin-10 (IL-10) at admission was associated with risk of death. However, no cluster of immune/inflammatory biomarkers at early timepoints was associated with mortality. HLA-DR molecules on monocytes at admission were associated with bacterial infections and septic shock. Later altered immune/inflammatory responses in patients who died may had been driven by the development of septic shock.Conclusion: Burn injury induced an early and profound upregulation of adaptive immunity and activation biomarkers and a down regulation of innate immunity and stress/inflammation biomarkers. Immune and inflammatory responses were associated with bacterial infection and septic shock. Absence of immune recovery patterns was associated with poor prognosis.

scholarly journals MD Simulations on a Well-Built Docking Model Reveal Fine Mechanical Stability and Force-Dependent Dissociation of Mac-1/GPIbα Complex

2021 ◽  
Vol 8 ◽  
Author(s):  
Xiaoyan Jiang ◽  
Xiaoxi Sun ◽  
Jiangguo Lin ◽  
Yingchen Ling ◽  
Ying Fang ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Molecular Basis ◽  
Mechanical Stability ◽  
Inflammatory Responses ◽  
Bond Number ◽  
Complex Model ◽  
Platelet Glycoprotein ◽  
Regulation Mechanism ◽  
Dissociation Probability ◽  
Docking Model

Interaction of leukocyte integrin macrophage-1 antigen (Mac-1) to platelet glycoprotein Ibα (GPIbα) is critical for platelet–leukocyte crosstalk in hemostasis and inflammatory responses to vessel injuries under hemodynamic environments. The mechano-regulation and its molecular basis for binding of Mac-1 to GPIbα remain unclear, mainly coming from the lack of crystal structure of the Mac-1/GPIbα complex. We herein built a Mac-1/GPIbα complex model through a novel computer strategy, which included a flexible molecular docking and system equilibrium followed by a “force-ramp + snapback” molecular dynamics (MD) simulation. With this model, a series of “ramp-clamp” steered molecular dynamics (SMD) simulations were performed to examine the GPIbα–Mac-1 interaction under various loads. The results demonstrated that the complex was mechano-stable for both the high rupture force (>250 pN) at a pulling velocity of 3 Å/ns and the conformational conservation under various constant tensile forces (≤75 pN); a catch-slip bond transition was predicted through the dissociation probability, examined with single molecular AFM measurements, reflected by the interaction energy and the interface H-bond number, and related to the force-induced allostery of the complex; besides the mutation-identified residues D222 and R218, the residues were also dominant in the binding of Mac-1 to GPIbα. This study recommended a valid computer strategy for building a likely wild-type docking model of a complex, provided a novel insight into the mechanical regulation mechanism and its molecular basis for the interaction of Mac-1 with GPIbα, and would be helpful for understanding the platelet–leukocyte interaction in hemostasis and inflammatory responses under mechano-microenvironments.

scholarly journals Interferon Regulatory Factor 5  Mediates Lipopolysaccharide Induced Neuroinflammation

2020 ◽  
Author(s):  
Ziqi Fan ◽  
Shuai Zhao ◽  
Yueli Zhu ◽  
Zheyu Li ◽  
Zhirong Liu ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Inflammatory Responses ◽  
Interferon Regulatory Factor ◽  
Microglial Cells ◽  
Regulatory Factor ◽  
Down Regulation ◽  
Interferon Regulatory Factor 5 ◽  
Bv2 Microglial Cells ◽  
Lps Treatment ◽  
Pro Inflammatory Cytokines

Abstract Background Activated microglia plays a vital role in neuroinflammation in central nervous system (CNS), which is associated with the pathogenesis and the progression of neurological diseases. Interferon regulatory factor 5 (IRF5) has been well established participating in inflammatory responses and is highly expressed in M1 macrophage in periphery, the role of which in the CNS remains elusive. Methods Lipopolysaccharide (LPS) was employed to induce neuroinflammation. Down-regulation of IRF5 in C57/BL6 mice and BV2 microglial cells were achieved by IRF5 siRNA transfection. The levels of pro-inflammatory cytokines were evaluated by ELISA and quantitative real-time PCR. The expression levels of IRF5 were examined by immnunofluorescence and Western blot. Results LPS induced significantly elevated expression of IRF5 in mouse brain, which co-localized with CD11b positive microglia. Down-regulation of IRF5 quenched the pro-inflammatory responses. The levels of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 were up-regulated at 4 h after LPS treatment, which were significantly down-regulated with the knockdown of IRF5. LPS-induced pro-inflammatory responses were transient, which returned to basal level at 24 h after LPS treatment. However, LPS did not up-regulate the expression of IRF5 in BV2 microglial cells, indicating that LPS-induced inflammation in BV2 cells does not involve IRF5 signaling. Conclusions IRF5 mediates the inflammatory responses in the CNS, which might serve as a therapeutic target for CNS inflammatory diseases. LPS-induced inflammation does not involve IRF5 signaling in BV2 microglia.

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