Cytokine and Eicosanoid Production by Cultured Human Monocytes Exposed to Titanium Particulate Debris

Phagocytosis of particulate wear debris from arthroplasties by macrophages induces an inflammatory response that has been linked to implant loosening and premature failure of artificial joints. Inflammatory mediators released by phagocytic macrophages such as tumor necrosis factor-a (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and prostaglandin E2 (PGE2) are believed to play a central role in the pathogenesis of aseptic loosening. The objective of this study was to characterize titanium alloy particulates that closely match wear debris found around joint arthroplasties and to study their effects on the biosynthesis of inflammatory mediators by cultured monocytes. Peripheral blood monocytes were isolated from healthy human volunteers. Monocytes were cultured in 96-well plates for 24 h, washed, and exposed to three concentrations of titanium particulates and controls from 18Ð24 h. Supernatants were assayed for TNF-α, IL-1β, IL-6, and PGE2 activity. Energy dispersive X-ray spectroscopy (EDX) verified the titanium alloy to be Ti6A14V. Scanning electron microscopy (SEM) analysis showed significant titanium particulate heterogeneity with approximately 95% of the particles <1 micrometer in diameter. SEM and EDX technology was useful in the characterization of the titanium particulates utilized for in vitro models of titanium-induced cytokine release by monocytes. Incubation of titanium particulates (in concentrations similar to those found around loosened prosthetic joints) with cultured monocytes significantly increased their production of TNF-α, IL-1β, and PGE2.

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Characterization of Titanium Alloy Particulates to Study the in Vitro Release of Inflammatory Mediators by Human Peripheral Blood Monocytes.

Microscopy and Microanalysis ◽

10.1017/s143192760002482x ◽

1998 ◽

Vol 4 (S2) ◽

pp. 940-941

Author(s):

B.J. Darien ◽

P. Sims ◽

T. Robinson ◽

P. Manley ◽

R. Albrecht

Keyword(s):

Titanium Alloy ◽

Inflammatory Mediators ◽

Peripheral Blood ◽

Wear Debris ◽

In Vitro Release ◽

Premature Failure ◽

Artificial Joints ◽

Mediators Of Inflammation ◽

Joint Arthroplasties

Particulate wear debris found around joint arthroplasties has been linked to the premature failure of artificial joints. Cytokines and eicosanoids released by macrophages are known mediators of inflammation and osteolysis. Previous in vitro studies of wear debris-mediated inflammation have relied upon poorly characterized particulates and peripheral blood cell fractions of mixed cellular composition. The objective of this study was to utilize titanium particulates that closely match wear debris found around joint arthroplasties and to study their effects on the biosynthesis of inflammatory mediators by isolated monocytes.To mimic wear debris that surrounds artificial joints, titanium alloy particulates (1-3 μm in diameter) were obtained. A submicron fraction of these particulates was isolated by differential sedimentation. The morphology, size and concentration of the resulting population was characterized utilizing scanning electron microscopy. Titanium particulate size was estimated from photomicrographs of calibrated latex microspheres mixed with titanium particles (Figure 1). A known volume of titanium particulates in suspension was applied to a carbon planchette and allowed to dry.

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Expression of the Metalloproteinase ADAM8 Is Upregulated in Liver Inflammation Models and Enhances Cytokine Release In Vitro

Mediators of Inflammation ◽

10.1155/2021/6665028 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17

Author(s):

Tanzeela Awan ◽

Aaron Babendreyer ◽

Justyna Wozniak ◽

Abid Mahmood Alvi ◽

Viktor Sterzer ◽

...

Keyword(s):

Cell Lines ◽

Inflammatory Mediators ◽

Liver Tissue ◽

Stellate Cell ◽

Hepatoma Cell ◽

Cell Types ◽

Chronic Liver ◽

Liver Inflammation ◽

Tnf Α

Acute and chronic liver inflammation is driven by cytokine and chemokine release from various cell types in the liver. Here, we report that the induction of inflammatory mediators is associated with a yet undescribed upregulation of the metalloproteinase ADAM8 in different murine hepatitis models. We further show the importance of ADAM8 expression for the production of inflammatory mediators in cultured liver cells. As a model of acute inflammation, we investigated liver tissue from lipopolysaccharide- (LPS-) treated mice in which ADAM8 expression was markedly upregulated compared to control mice. In vitro, stimulation with LPS enhanced ADAM8 expression in murine and human endothelial and hepatoma cell lines as well as in primary murine hepatocytes. The enhanced ADAM8 expression was associated with an upregulation of TNF-α and IL-6 expression and release. Inhibition studies indicate that the cytokine response of hepatoma cells to LPS depends on the activity of ADAM8 and that signalling by TNF-α can contribute to these ADAM8-dependent effects. The role of ADAM8 was further confirmed with primary hepatocytes from ADAM8 knockout mice in which TNF-α and IL-6 induction and release were considerably attenuated. As a model of chronic liver injury, we studied liver tissue from mice undergoing high-fat diet-induced steatohepatitis and again observed upregulation of ADAM8 mRNA expression compared to healthy controls. In vitro, ADAM8 expression was upregulated in hepatoma, endothelial, and stellate cell lines by various mediators of steatohepatitis including fatty acid (linoleic-oleic acid), IL-1β, TNF-α, IFN-γ, and TGF-β. Upregulation of ADAM8 was associated with the induction and release of proinflammatory cytokines (TNF-α and IL-6) and chemokines (CX3CL1). Finally, knockdown of ADAM8 expression in all tested cell types attenuated the release of these mediators. Thus, ADAM8 is upregulated in acute and chronic liver inflammation and is able to promote inflammation by enhancing expression and release of inflammatory mediators.

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Effects of Caffeoylquinic Acid Derivatives and C-Flavonoid from Lychnophora ericoides on in vitro Inflammatory Mediator Production

Natural Product Communications ◽

10.1177/1934578x1000500512 ◽

2010 ◽

Vol 5 (5) ◽

pp. 1934578X1000500 ◽

Cited By ~ 6

Author(s):

Michel David dos Santos ◽

Guanjie Chen ◽

Maria Camila Almeida ◽

Denis Melo Soares ◽

Glória Emília Petto de Souza ◽

...

Keyword(s):

Inflammatory Mediators ◽

Cultured Cells ◽

Dependent Manner ◽

Caffeoylquinic Acid ◽

Inflammatory Mediator Production ◽

Dicaffeoylquinic Acid ◽

Tnf Α ◽

Dose Dependent Fashion ◽

Dose Dependent

In this study we aimed at evaluating the effect of the major polar constituents of the medicinal plant Lychnophora ericoides on the production of inflammatory mediators produced by LPS-stimulated U-937 cells. The 6,8-di- C-β-glucosylapigenin (vicenin-2) presented no effect on tumor necrosis factor (TNF)-α production, but inhibited, in a dose-dependent manner, the production of prostaglandin (PG) E2 without altering the expression of cyclooxygenase (COX) -2 protein. 3,5-Dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid, at lower concentrations, had small but significant effects on reducing PGE2 levels; at higher doses these compounds stimulated PGE2 and also TNF-α production by the cells. All the caffeoylquinic acid derivatives, in a dose-dependent fashion, were able to inhibit monocyte chemoattractant protein-3 synthesis/release, with 4,5-DCQ being the most potent at the highest tested concentration. These results add important information on the effects of plant natural polyphenols, namely vicenin-2 and caffeoylquinic acid derivatives, on the production of inflammatory mediators by cultured cells.

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Nerolidol Mitigates Colonic Inflammation: An Experimental Study Using both In Vivo and In Vitro Models

Nutrients ◽

10.3390/nu12072032 ◽

2020 ◽

Vol 12 (7) ◽

pp. 2032

Author(s):

Vishnu Raj ◽

Balaji Venkataraman ◽

Saeeda Almarzooqi ◽

Sanjana Chandran ◽

Shreesh K. Ojha ◽

...

Keyword(s):

Nuclear Translocation ◽

In Vitro Models ◽

Mrna Levels ◽

Colonic Inflammation ◽

Tnf Α ◽

Cox 2 ◽

Anti Inflammatory ◽

Ht 29

Nerolidol (NED) is a naturally occurring sesquiterpene alcohol present in various plants with potent anti-inflammatory effects. In the current study, we investigated NED as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J) were administered 3% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colitis. Six groups received either vehicle alone or DSS alone or DSS with oral NED (50, 100, and 150 mg/kg body weight/day by oral gavage) or DSS with sulfasalazine. Disease activity index (DAI), colonic histology, and biochemical parameters were measured. TNF-α-treated HT-29 cells were used as in vitro model of colonic inflammation to study NED (25 µM and 50 µM). NED significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue Myeloperoxidase (MPO) concentrations, neutrophil and macrophage mRNA expression (CXCL2 and CCL2), and proinflammatory cytokine content (IL-1β, IL-6, and TNF-α) both at the protein and mRNA level were significantly reduced by NED. The increase in content of the proinflammatory enzymes, COX-2 and iNOS induced by DSS were also significantly inhibited by NED along with tissue nitrate levels. NED promoted Nrf2 nuclear translocation dose dependently. NED significantly increased antioxidant enzymes activity (Superoxide dismutase (SOD) and Catalase (CAT)), Hemeoxygenase-1 (HO-1), and SOD3 mRNA levels. NED treatment in TNF-α-challenged HT-29 cells significantly decreased proinflammatory chemokines (CXCL1, IL-8, CCL2) and COX-2 mRNA levels. NED supplementation attenuates colon inflammation through its potent antioxidant and anti-inflammatory activity both in in vivo and in vitro models of colonic inflammation.

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Upregulation of miR-216a exerts neuroprotective effects against ischemic injury through negatively regulating JAK2/STAT3-involved apoptosis and inflammatory pathways

Journal of Neurosurgery ◽

10.3171/2017.5.jns163165 ◽

2019 ◽

Vol 130 (3) ◽

pp. 977-988 ◽

Cited By ~ 10

Author(s):

Yu Shuang Tian ◽

Di Zhong ◽

Qing Qing Liu ◽

Xiu Li Zhao ◽

Hong Xue Sun ◽

...

Keyword(s):

Ischemic Stroke ◽

Inflammatory Mediators ◽

Neurological Deficit ◽

Ischemic Injury ◽

Glucose Deprivation ◽

Luciferase Assay ◽

Oxygen Glucose Deprivation ◽

Tnf Α

OBJECTIVEIschemic stroke remains a significant cause of death and disability in industrialized nations. Janus tyrosine kinase (JAK) and signal transducer and activator of transcription (STAT) of the JAK2/STAT3 pathway play important roles in the downstream signal pathway regulation of ischemic stroke–related inflammatory neuronal damage. Recently, microRNAs (miRNAs) have emerged as major regulators in cerebral ischemic injury; therefore, the authors aimed to investigate the underlying molecular mechanism between miRNAs and ischemic stroke, which may provide potential therapeutic targets for ischemic stroke.METHODSThe JAK2- and JAK3-related miRNA (miR-135, miR-216a, and miR-433) expression levels were detected by real-time quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot analysis in both oxygen-glucose deprivation (OGD)–treated primary cultured neuronal cells and mouse brain with middle cerebral artery occlusion (MCAO)–induced ischemic stroke. The miR-135, miR-216a, and miR-433 were determined by bioinformatics analysis that may target JAK2, and miR-216a was further confirmed by 3′ untranslated region (3′UTR) dual-luciferase assay. The study further detected cell apoptosis, the level of lactate dehydrogenase, and inflammatory mediators (inducible nitric oxide synthase [iNOS], matrix metalloproteinase–9 [MMP-9], tumor necrosis factor–α [TNF-α], and interleukin-1β [IL-1β]) after cells were transfected with miR-NC (miRNA negative control) or miR-216a mimics and subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) damage with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, annexin V–FITC/PI, Western blots, and enzyme-linked immunosorbent assay detection. Furthermore, neurological deficit detection and neurological behavior grading were performed to determine the infarction area and neurological deficits.RESULTSJAK2 showed its highest level while miR-216a showed its lowest level at day 1 after ischemic reperfusion. However, miR-135 and miR-433 had no obvious change during the process. The luciferase assay data further confirmed that miR-216a can directly target the 3′UTR of JAK2, and overexpression of miR-216a repressed JAK2 protein levels in OGD/R-treated neuronal cells as well as in the MCAO model ischemic region. In addition, overexpression of miR-216a mitigated cell apoptosis both in vitro and in vivo, which was consistent with the effect of knockdown of JAK2. Furthermore, the study found that miR-216a obviously inhibited the inflammatory mediators after OGD/R, including inflammatory enzymes (iNOS and MMP-9) and cytokines (TNF-α and IL-1β). Upregulating miR-216a levels reduced ischemic infarction and improved neurological deficit.CONCLUSIONSThese findings suggest that upregulation of miR-216a, which targets JAK2, could induce neuroprotection against ischemic injury in vitro and in vivo, which provides a potential therapeutic target for ischemic stroke.

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Silibinin Downregulates the NF-κB Pathway and NLRP1/NLRP3 Inflammasomes in Monocytes from Pregnant Women with Preeclampsia

Molecules ◽

10.3390/molecules24081548 ◽

2019 ◽

Vol 24 (8) ◽

pp. 1548 ◽

Cited By ~ 18

Author(s):

Mariana Leticia Matias ◽

Virginia Juliani Gomes ◽

Mariana Romao-Veiga ◽

Vanessa Rocha Ribeiro ◽

Priscila Rezeck Nunes ◽

...

Keyword(s):

Pregnant Women ◽

Immunological Response ◽

Response Characteristic ◽

Sterile Inflammation ◽

Blood Monocytes ◽

Specific Syndrome ◽

Tnf Α ◽

Gene And Protein Expression ◽

Nlrp3 Inflammasomes

Preeclampsia (PE) is a human pregnancy-specific syndrome with abnormal activation of cells from the innate immune system. The present study evaluated whether silibinin (SB) treatment of monocytes from preeclamptic women could modulate NLRP1 and NLRP3 inflammasomes as well as TLR4/NF-κB pathway activation. Peripheral blood monocytes from 20 preeclamptic and 20 normotensive (NT) pregnant women, as well as the THP-1 cell line, were cultured with or without monosodium urate (MSU) or SB. NLRP1, NLRP3, Caspase-1, TLR4, MyD88, NF-κB, IL-1β, IL-18, TNF-α and IL-10 gene expression by monocytes was analysed by quantitative real-time polymerase chain reaction (qPCR), while inflammatory cytokine production and p65NF-κB activity were determined by enzyme-linked immunosorbent assays (ELISAs). TLR4/MyD88/NF-κB and NLRP1/NLRP3 inflammasomes pathways in THP-1 cells were evaluated by flow cytometry and western blot respectively. Compared with NT women, monocytes from preeclamptic women showed The Ethics Committee of the Botucatu Medical School approved the study (protocol number 2.333.216)higher endogenous activation of NLRP1/NLRP3 inflammasomes and the TLR4/NF-κB pathway as well as higher gene and protein expression of IL-1β, IL-18 and TNF-α, and lower expression of IL-10. Monocyte stimulation with MSU increased inflammation-related genes as well as NF-κB activity. In vitro, SB treatment of monocytes from preeclamptic women reduced the basal activation of these cells by decreasing NLRP1/NLRP3 inflammasomes and p65NF-κB activity. THP-1 cells exhibited a similar immunological response profile to monocytes from preeclamptic women when cultured with or without MSU or SB. These results suggest uric acid participates in the systemic inflammatory response characteristic of preeclampsia and that in vitro SB treatment can modulate the sterile inflammation established in monocytes from preeclamptic women.

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Monocyte Derivatives Promote Angiogenesis and Myocyte Survival in a Model of Myocardial Infarction

Cell Transplantation ◽

10.3727/096368909x484266 ◽

2010 ◽

Vol 19 (4) ◽

pp. 369-386 ◽

Cited By ~ 24

Author(s):

M. Bouchentouf ◽

P. Paradis ◽

K. A. Forner ◽

J. Cuerquis ◽

M. N. Boivin ◽

...

Keyword(s):

Myocardial Infarction ◽

Endothelial Cell ◽

Mononuclear Cells ◽

Endothelial Cell Proliferation ◽

Blood Monocytes ◽

Vascular Networks ◽

Peripheral Blood Mononuclear ◽

Mature Endothelial Cell ◽

Tnf Α

In this study, we have investigated the hypothesis that previously reported beneficial effect of peripheral blood mononuclear cells cultured under angiogenic conditions on cardiovascular function following ischemia is not limited to EPCs but also to monocytes contained therein. We first purified and analyzed the phenotype and secretome of human and murine blood monocytes cultured under angiogenic conditions (named MDs for monocyte derivatives) and tested their effect in a mouse model of myocardial infarction (MI). FACS analysis of MDs shows that these cells express mature endothelial cell markers and that their proliferative capacity is virtually absent, consistent with their end-differentiated monocytic ontogeny. MDs secreted significant levels of HGF, IGF-1, MCP-1, and sTNFR-1 relative to their monocyte precursors. MDs were unable to form vascular networks in vitro when cultured on matrix coated flasks. Treatment of murine HL-1 cardiomyocyte cell line with MD-conditioned medium reduced their death induced by TNF-α, staurosporine, and oxidative stress, and this effect was dependent upon MD-derived sTNFR-1, HGF, and IGF-1. We further demonstrate that MD secretome promoted endothelial cell proliferation and capacity to form vessels in vitro and this was dependent upon MD-derived MCP-1, HGF, and IGF-1. Echocardiography analysis showed that MD myocardial implantation improved left ventricle fractional shortening of mouse hearts following MI and was associated with reduced myocardial fibrosis and enhancement of angiogenesis. Transplanted MDs and their secretome participate in preserving functional myocardium after ischemic insult and attenuate pathological remodeling.

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The effect of marine oil-derived n-3 fatty acids on transepithelial calcium transport in Caco-2 cell models of healthy and inflamed intestines

British Journal Of Nutrition ◽

10.1017/s0007114507201758 ◽

2007 ◽

Vol 97 (2) ◽

pp. 281-288 ◽

Cited By ~ 4

Author(s):

Jennifer Gilman ◽

Kevin D. Cashman

Keyword(s):

Fatty Acids ◽

Crohn’S Disease ◽

Crohn's Disease ◽

Human Subjects ◽

Healthy Human ◽

Marine Oil ◽

Ca Transport ◽

Tnf Α

Marine oil-derived n-3 fatty acids have been shown to stimulate intestinal Ca absorption in animal studies, but the effects of such fatty acids on Ca absorption in human subjects are relatively unknown. In particular, n-3 fatty acids may be of therapeutic value for some Crohn's disease patients who experience Ca malabsorption. Therefore, the aim of the present study was to investigate the effect of 20 : 5n-3 and 22 : 6n-3 on transepithelial Ca transport across monolayers of healthy Caco-2 cells as well as of TNF-α-treated Caco-2 cells (an in vitro model of Crohn's disease). Caco-2 cells were seeded onto permeable filter supports and allowed to differentiate into monolayers, which were treated with 80 μm-20 : 5n-3, 80 μm-22 : 6n-3, or 40 μm-20 : 5n-3+40 μm-22 : 6n-3 for 6 or 8 d, with or without co-treatment with TNF-α (10 ng/ml) (n 11–15 monolayers per treatment). On day 16, transepithelial and transcellular transport of 45Ca and fluorescein transport (a marker of paracellular diffusion) were measured. Treatment of healthy and inflamed Caco-2 cells with 20 : 5n-3, 22 : 6n-3 and both fatty acids combined for 8 d significantly (P < 0·005–0·01) increased total transepithelial Ca transport compared with that in control, effects which were mediated by an enhanced rate of transcellular Ca transport. The effects of n-3 fatty acids on Ca absorption after 6 d were less clear-cut. In conclusion, the present in vitro findings highlight the need to investigate the effect of marine oil-based n-3 fatty acids on Ca absorption in vivo in studies of healthy human subjects as well as of Crohn's disease patients.

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