scholarly journals A Novel Peptide Oligomer of Bacitracin Induces M1 Macrophage Polarization by Facilitating Ca2+ Influx

Nutrients ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1603
Author(s):  
Seon Yeong Ji ◽  
Hyesook Lee ◽  
Hyun Hwangbo ◽  
Su-Hyun Hong ◽  
Hee-Jae Cha ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Signaling Pathway ◽  
Inflammatory Mediators ◽  
Macrophage Polarization ◽  
Mitogen Activated Protein Kinase ◽  
Raw 264.7 Cells ◽  
Macrophage Phenotype ◽  
Cytokines And Chemokines ◽  
M1 Macrophage ◽  
Bacillus Spp

Antimicrobial peptides (AMPs) are components of the innate immune system and form the first defense against pathogens for various organisms. In the present study, we assessed whether CSP32, a novel AMP oligomer of bacitracin isolated from a strain of Bacillus spp., regulates the polarization of murine macrophage-like RAW 264.7 cells. CSP32 stimulated phagocytosis while inducing the appearance of the typical M1 polarized macrophage phenotype; these M1 macrophages play a role in host defense against pathogens. Furthermore, our results showed that CSP32 enhanced the expression and production of pro-inflammatory mediators, such as cytokines and chemokines. In addition, the CSP32-stimulated inflammatory mediators were induced mainly by the mitogen-activated protein kinase/nuclear factor kappa B (MAPK/NF-κB) signaling pathway during M1 macrophage polarization. In particular, CSP32 markedly increased the numbers of Ca2+-positive macrophages while upregulating phospholipase C and activating protein kinase Cε. Furthermore, the inhibition of intracellular Ca2+ by BAPTA-AM, a Ca2+ chelator, significantly suppressed the CSP32-mediated phagocytosis, inflammatory mediator production, and NF-κB activation. In conclusion, our data suggested that CSP32-stimulated M1 macrophage polarization is dependent on the calcium signaling pathway and may result in enhanced immune capacities.

scholarly journals Receptor Activator of NF-κB Ligand (RANKL) Activates TAK1 Mitogen-Activated Protein Kinase Kinase Kinase through a Signaling Complex Containing RANK, TAB2, and TRAF6

2002 ◽  
Vol 22 (4) ◽  
pp. 992-1000 ◽  
Author(s):  
Junko Mizukami ◽  
Giichi Takaesu ◽  
Hiroyuki Akatsuka ◽  
Hiroaki Sakurai ◽  
Jun Ninomiya-Tsuji ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Signaling Pathway ◽  
Dominant Negative ◽  
Mitogen Activated Protein Kinase ◽  
Raw 264.7 Cells ◽  
Iκb Kinase ◽  
Receptor Activator ◽  
Mitogen Activated Protein ◽  
Rank Signaling ◽  
Rankl Stimulation

ABSTRACT The receptor activator of NF-κB (RANK) and its ligand RANKL are key molecules for differentiation and activation of osteoclasts. RANKL stimulates transcription factors AP-1 through mitogen-activated protein kinase (MAPK) activation, and NF-κB through IκB kinase (IKK) activation. Tumor necrosis factor receptor-associated factor 6 (TRAF6) is essential for activation of these kinases. In the interleukin-1 signaling pathway, TAK1 MAPK kinase kinase (MAPKKK) mediates MAPK and IKK activation via interaction with TRAF6, and TAB2 acts as an adapter linking TAK1 and TRAF6. Here, we demonstrate that TAK1 and TAB2 participate in the RANK signaling pathway. Dominant negative forms of TAK1 and TAB2 inhibit NF-κB activation induced by overexpression of RANK. In 293 cells stably transfected with full-length RANK, RANKL stimulation facilitates the formation of a complex containing RANK, TRAF6, TAB2, and TAK1, leading to the activation of TAK1. Furthermore, in murine monocyte RAW 264.7 cells, dominant negative forms of TAK1 and TAB2 inhibit NF-κB activation induced by RANKL and endogenous TAK1 is activated in response to RANKL stimulation. These results suggest that the formation of the TRAF6-TAB2-TAK1 complex is involved in the RANK signaling pathway and may regulate the development and function of osteoclasts.

scholarly journals Natural feed contaminant zearalenone decreases the expressions of important pro- and anti-inflammatory mediators and mitogen-activated protein kinase/NF-κB signalling molecules in pigs

2013 ◽  
Vol 111 (3) ◽  
pp. 452-464 ◽  
Author(s):  
Gina Cecilia Pistol ◽  
Mihail Alexandru Gras ◽  
Daniela Eliza Marin ◽  
Florentina Israel-Roming ◽  
Mariana Stancu ◽  
...  
Keyword(s):  
Immune Response ◽  
Protein Kinase ◽  
Matrix Metalloproteinases ◽  
Inflammatory Mediators ◽  
Interferon Γ ◽  
Mitogen Activated Protein Kinase ◽  
Economic Point ◽  
Mitogen Activated Protein ◽  
Anti Inflammatory

Zearalenone (ZEA) is an oestrogenic mycotoxin produced byFusariumspecies, considered to be a risk factor from both public health and agricultural perspectives. In the presentin vivostudy, a feeding trial was conducted to evaluate thein vivoeffect of a ZEA-contaminated diet on immune response in young pigs. The effect of ZEA on pro-inflammatory (TNF-α, IL-8, IL-6, IL-1β and interferon-γ) and anti-inflammatory (IL-10 and IL-4) cytokines and other molecules involved in inflammatory processes (matrix metalloproteinases (MMP)/tissue inhibitors of matrix metalloproteinases (TIMP), nuclear receptors: PPARγ and NF-κB1, mitogen-activated protein kinases (MAPK): mitogen-activated protein kinase kinase kinase 7 (TAK1)/mitogen-activated protein kinase 14 (p38α)/mitogen-activated protein kinase 8 (JNK1)/ mitogen-activated protein kinase 9 (JNK2)) in the liver of piglets was investigated. The present results showed that a concentration of 316 parts per billion ZEA leads to a significant decrease in the levels of pro- and anti-inflammatory cytokines at both gene expression and protein levels, correlated with a decrease in the levels of other inflammatory mediators, MMP and TIMP. The results also showed that dietary ZEA induces a dramatic reduction in the expressions ofNF-κB1andTAK1/p38αMAPK genes in the liver of the experimentally intoxicated piglets, and has no effect on the expression ofPPARγmRNA. The present results suggest that the toxic action of ZEA begins in the upstream of the MAPK signalling pathway by the inhibition of TAK1, a MAPK/NF-κB activator. In conclusion, the present study shows that ZEA alters several important parameters of the hepatic cellular immune response. From an economic point of view, these data suggest that, in pigs, ZEA is not only a powerful oestrogenic mycotoxin but also a potential hepatotoxin when administered through the oral route. Therefore, the present results represent additional data from cellular and molecular levels that could be taken into account in the determination of the regulation limit of the tolerance to ZEA.

Abstract 11059: Role of Sirtuin 6 in Macrophage Polarization and Cardiac Repair in Diabetes

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Rajarajan A Thandavarayan ◽  
Darukeshwara Joladarashi ◽  
Sahana S Babu ◽  
Garikipati V Srikanth ◽  
Alexander R Mackie ◽  
...  
Keyword(s):  
Macrophage Polarization ◽  
Experimental Studies ◽  
Peritoneal Macrophages ◽  
Left Ventricular ◽  
Cardiac Repair ◽  
Raw 264.7 Cells ◽  
Mouse Bone Marrow ◽  
Macrophage Phenotype ◽  
Intramyocardial Injection ◽  
M2 Phenotype

Clinical and experimental studies provide evidence that metabolic and inflammatory pathways are functionally interconnected to cardiovascular diseases. Dynamic changes in macrophage activation [classical M1 activation (promote inflammation) or alternative M2 activation (promote wound healing)], in response to various stress signals, modulate cardiac physiopathology in diabetes. Sirtuin 6 (SIRT6), a NAD-dependent nuclear deacetylase plays an important role in genomic stability, cellular metabolism, stress response and aging. However, the mechanism by which SIRT6 activity affects macrophage phenotype and cardiac function in diabetes is still unexplored. Mouse bone marrow-derived macrophages (BMM) exposed to high glucose (HG, 25mM D-glucose) showed reduced expression of SIRT6 as compared to low glucose (LG, 5mM D-glucose)- and osmotic control (OC, 5mM D-glucose+20mM D-mannitol)-treated cells, associated with increased expression of proinflammatory cytokine and transcription factors (NFkb, c-JUN, FOXO, SP1 and STAT1). In addition, SIRT6 level was reduced in peritoneal macrophages of both diabetic models (streptozotocin-induced and db/db mice) as compared to non-diabetic mice. SIRT6 knockdown in RAW 264.7 cells exaggerated inflammatory response when exposed to HG. In contrast, IL-4-induced increase in mRNA expression of macrophage M2 phenotype markers like Arg1, Chi4l4, Retnla and IRS-2, but not IRS-1 expression was repressed suggesting that alternative macrophage (M2) phenotype was defective in SIRT6 deficient BM-macrophages under HG condition. SIRT6 protein expression was low in myocardial infarction-induced (MI) and diabetes-affected hearts. Interestingly, mice receiving intramyocardial injection of SIRT6-deficient macrophages showed further deterioration in left ventricular function, post-MI. Taken together, these data highlight a role for SIRT6 in regulating the balance of M1/M2 polarization, therefore, modulate macrophage mediated cardiac repair and regeneration in numerous inflammatory disease states including diabetes

scholarly journals The Role of Toll-Like Receptors in the Production of Cytokines by Human Lung Macrophages

2018 ◽  
Vol 12 (1) ◽  
pp. 63-73 ◽  
Author(s):  
Stanislas Grassin-Delyle ◽  
Charlotte Abrial ◽  
Hélène Salvator ◽  
Marion Brollo ◽  
Emmanuel Naline ◽  
...  
Keyword(s):  
Human Lung ◽  
Macrophage Phenotype ◽  
Chemokine Production ◽  
Lung Macrophages ◽  
Cytokines And Chemokines ◽  
M1 Macrophage ◽  
Microbial Infections ◽  
Selective Agonists ◽  
And Function ◽  
Subtype Selective

Background: The Toll-like receptor (TLR) family is involved in the recognition of and response to microbial infections. These receptors are expressed in leukocytes. TLR stimulation induces the production of proinflammatory cytokines and chemokines. Given that human lung macrophages (LMs) constitute the first line of defense against inhaled pathogens, the objective of this study was to investigate the expression and function of TLR subtypes in this cell population. Methods: Human primary LMs were obtained from patients undergoing surgical resection. The RNA and protein expression levels of TLRs, chemokines, and cytokines were assessed after incubation with subtype-selective agonists. Results: In human LMs, the TLR expression level varied from one subtype to another. Stimulation with subtype-selective agonists induced an intense, concentration- and time-dependent increase in the production of chemokines and cytokines. TLR4 stimulation induced the strongest effect, whereas TLR9 stimulation induced a much weaker response. Conclusions: The stimulation of TLRs in human LMs induces intense cytokine and chemokine production, a characteristic of the proinflammatory M1 macrophage phenotype.

Sign in / Sign up

Export Citation Format

Share Document