Dietary Oleocanthal Supplementation Prevents Inflammation and Oxidative Stress in Collagen-Induced Arthritis in Mice

Oleocanthal (OLE), a characteristic and exclusive secoiridoid of Oleoaceae family, is mainly found in extra virgin olive oil (EVOO). Previous studies have reported its antioxidant, anti-inflammatory, antimicrobial, anticancer and neuroprotective effects. Since the pathogenesis of rheumatoid arthritis (RA) involves inflammatory and oxidative components, this study was designed to evaluate the preventive role of dietary OLE-supplemented effects in collagen-induced arthritis (CIA) murine model. Animals were fed with a preventive OLE-enriched dietary during 6 weeks previous to CIA induction and until the end of experiment time. At day 43 after first immunization, mice were sacrificed: blood was recollected and paws were histological and biochemically processed. Dietary OLE prevented bone, joint and cartilage rheumatic affections induced by collagen. Levels of circulatory matrix metalloproteinase (MMP)-3 and pro-inflammatory cytokines (IL-6, IL-1β, TNF-α, IL-17, IFN-γ) were significantly decreased in secoiridoid fed animals. Besides, dietary OLE was able to diminish COX-2, mPGES-1 and iNOS protein expressions and, also, PGE2 levels. The mechanisms underlying these protective effects could be related to Nrf-2/HO-1 axis activation and the inhibition of relevant signaling pathways including JAK-STAT, MAPKs and NF-κB, thus controlling the production of inflammatory and oxidative mediators. Overall, our results exhibit preliminary evidences about OLE, as a novel dietary tool for the prevention of autoimmune and inflammatory disorders, such as RA.

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Role of gambogenic acid in regulating PI3K/Akt/NF-kβ signaling pathways in rat model of acute hepatotoxicity

Bioscience Biotechnology and Biochemistry ◽

10.1093/bbb/zbaa039 ◽

2021 ◽

Vol 85 (3) ◽

pp. 520-527

Author(s):

Zhongyang Ding ◽

Ying Li ◽

Zhangfeng Tang ◽

Xiaoyi Song ◽

Fa Jing ◽

...

Keyword(s):

Signaling Pathways ◽

Caspase 3 ◽

Nuclear Factor ◽

Protective Effects ◽

Histopathological Changes ◽

Phosphatidylinositol 3 Kinase ◽

Tnf Α ◽

Protein Expressions ◽

Apoptosis Markers

ABSTRACT The purpose of this study is to investigate the protective effect of gambogenic acid (GA) in acetaminophen (APAP)-induced hepatotoxicity in rat models. GA (10 mg/kg) was administered intraperitoneal (i.p.) to rats for 7 consecutive days followed by APAP (500 mg/kg) single dose (i.p.) on the final day after GA administration. The levels of MDA, GSH, SOD, CAT, GPx, GST, ALP, AST, ALT, proinflammatory cytokines (TNF-α, IL-1β, IL-6), apoptosis markers (caspase-3 and -9, Bax, Bcl-2), 4-hydroxynonenal (4-HNE), and prostaglandin E2 (PGE2) were evaluated. Results exhibited protective effects of GA by inhibiting inflammation, preventing oxidative stress and apoptosis in APAP-induced liver. Histopathological changes caused by APAP were attenuated, protein expressions of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) were upregulated, and nuclear factor–kappa β (NF-kβ) was downregulated by GA. In summary, GA significantly exerted anti-inflammatory and antiapoptotic effects against APAP-induced hepatotoxicity potentially through regulation of PI3K/Akt and NF-kβ signaling pathways.

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Comparing the protective effects of resveratrol, curcumin and sulforaphane against LPS/IFN-γ-mediated inflammation in doxorubicin-treated macrophages

Scientific Reports ◽

10.1038/s41598-020-80804-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Haidy A. Saleh ◽

Eman Ramdan ◽

Mohey M. Elmazar ◽

Hassan M. E. Azzazy ◽

Anwar Abdelnaser

Keyword(s):

Nitric Oxide ◽

Inflammatory Response ◽

Raw 264.7 Cells ◽

Inos Mrna ◽

No Production ◽

Raw 264.7 ◽

Mrna Levels ◽

Protective Effects ◽

Tnf Α ◽

Ifn Γ

AbstractDoxorubicin (DOX) chemotherapy is associated with the release of inflammatory cytokines from macrophages. This has been suggested to be, in part, due to DOX-mediated leakage of endotoxins from gut microflora, which activate Toll-like receptor 4 (TLR4) signaling in macrophages, causing severe inflammation. However, the direct function of DOX on macrophages is still unknown. In the present study, we tested the hypothesis that DOX alone is incapable of stimulating inflammatory response in macrophages. Then, we compared the anti-inflammatory effects of curcumin (CUR), resveratrol (RES) and sulforaphane (SFN) against lipopolysaccharide/interferon-gamma (LPS/IFN-γ)-mediated inflammation in the absence or presence of DOX. For this purpose, RAW 264.7 cells were stimulated with LPS/IFN-γ (10 ng/mL/10 U/mL) in the absence or presence of DOX (0.1 µM). Our results showed that DOX alone is incapable of stimulating an inflammatory response in RAW 264.7 macrophages. Furthermore, after 24 h of incubation with LPS/IFN-γ, a significant increase in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and inducible nitric oxide synthase (iNOS) mRNA levels was observed. Similarly, nitric oxide (NO) production and TNF-α and IL-6 protein levels were significantly upregulated. Moreover, in LPS/IFN-γ-treated macrophages, the microRNAs (miRNAs) miR-146a, miR-155, and miR-21 were significantly overexpressed. Interestingly, upon testing CUR, RES, and SFN against LPS/IFN-γ-mediated inflammation, only SFN was able to significantly reverse the LPS/IFN-γ-mediated induction of iNOS, TNF-α and IL-6 and attenuate miR-146a and miR-155 levels. In conclusion, SFN, at the transcriptional and posttranscriptional levels, exhibits potent immunomodulatory action against LPS/IFN-γ-stimulated macrophages, which may indicate SFN as a potential treatment for DOX-associated inflammation.

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The 3-Year Effect of the Mediterranean Diet Intervention on Inflammatory Biomarkers Related to Cardiovascular Disease

Biomedicines ◽

10.3390/biomedicines9080862 ◽

2021 ◽

Vol 9 (8) ◽

pp. 862

Author(s):

Mireia Urpi-Sarda ◽

Rosa Casas ◽

Emilio Sacanella ◽

Dolores Corella ◽

Cristina Andrés-Lacueva ◽

...

Keyword(s):

Cardiovascular Disease ◽

Mediterranean Diet ◽

Virgin Olive Oil ◽

Extra Virgin Olive Oil ◽

Inflammatory Biomarkers ◽

Year Effect ◽

Tnf Α ◽

The Mediterranean ◽

Anti Inflammatory

The intervention with the Mediterranean diet (MD) pattern has evidenced short-term anti-inflammatory effects, but little is known about its long-term anti-inflammatory properties at molecular level. This study aims to investigate the 3-year effect of MD interventions compared to low-fat diet (LFD) on changes on inflammatory biomarkers related to atherosclerosis in a free-living population with a high-risk of cardiovascular disease (CD). Participants (n = 285) in the PREDIMED trial were randomly assigned into three intervention groups: MD with extra-virgin olive oil (EVOO) or MD-Nuts, and a LFD. Fourteen plasma inflammatory biomarkers were determined by Luminex assays. An additional pilot study of gene expression (GE) was determined by RT-PCR in 35 participants. After 3 years, both MDs showed a significant reduction in the plasma levels of IL-1β, IL-6, IL-8, TNF-α, IFN-γ, hs-CRP, MCP-1, MIP-1β, RANTES, and ENA78 (p < 0.05; all). The decreased levels of IL-1β, IL-6, IL-8, and TNF-α after MD significantly differed from those in the LFD (p < 0.05). No significant changes were observed at the gene level after MD interventions, however, the GE of CXCR2 and CXCR3 tended to increase in the control LFD group (p = 0.09). This study supports the implementation of MD as a healthy long-term dietary pattern in the prevention of CD in populations at high cardiovascular risk.

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POS0333 ALTERED MACROPHAGE POLARIZATION PHENOTYPES IN SYSTEMIC SCLEROSIS

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2021-eular.3124 ◽

2021 ◽

Vol 80 (Suppl 1) ◽

pp. 394.1-394

Author(s):

A. Hukara ◽

M. Rudnik ◽

C. B. Rufer ◽

O. Distler ◽

P. Blyszczuk ◽

...

Keyword(s):

Systemic Sclerosis ◽

Macrophage Polarization ◽

Peritoneal Macrophages ◽

Surface Marker ◽

Surface Marker Expression ◽

Tnf Α ◽

Ifn Γ ◽

Alternatively Activated ◽

Classically Activated

Background:Fos-like 2 (Fosl-2) is a transcription factor of the AP-1 family and has a broad range in inducing cellular changes affecting fibrosis and inflammatory responses. Pathological effects of Fosl-2 have been associated with systemic sclerosis (SSc). In addition, increased expression of Fosl-2 has been detected in human SSc monocyte-derived macrophages [1]. Monocytes and macrophages play a central role in activating and propagating acute inflammation followed by pathological fibrosis and organ dysfunction. The classification of the macrophage polarization phenotype can be assigned based on the stimulus, for example into classically-activated M(LPS), and alternatively-activated M(IL-4) macrophages [2]. However, the role of the Fosl-2 transcription factor in macrophage polarization remains elusive.Objectives:To investigate the role of Fosl-2 in macrophage polarization in SSc using Fosl-2 overexpressing transgenic (Fosl-2 tg) mice and human blood-derived macrophages from SSc patients.Methods:Thiogylcolate-elicited peritoneal macrophages were isolated from wild-type (wt) and Fosl-2 tg mice. Human peripheral CD14+ blood-derived monocytes were isolated and differentiated to macrophages (hMDM) from healthy controls and SSc patients. Murine and human macrophages were polarized with LPS (10 ng/ml), LPS + recombinant mouse IFN-γ (10 ng/ml), recombinant mouse, resp. human IL-4 (10 ng/ml) or remained untreated. Macrophage surface marker expression was assessed by flow cytometry using a mouse (F4/80, CD11b, CD86, CD80, CD38, MHCII, CD206, PD-L1, PD-L2, CD36) or human (CD38, CD40, CD86, PD-L2, PD-L1, CD163, CD206) designed polarization panel. Phagocytic activity was detected with pHrodo Red E.coli particles by flow cytometry. Gene expression and secretion of pro- and anti-inflammatory markers were measured by RT-qPCR, standard ELISAs and Griess Assay for nitric oxide production.Results:After LPS stimulation, mRNA levels of IL-1β (p<0.01, n=11-12), TNF-α (p=0.05, n=11-12) and IFN-γ (p<0.05, n=7) were reduced, whereas expression of IL-10 (p<0.05, n=11-12) was enhanced in Fosl-2 tg peritoneal macrophages in comparison to wt cells. Secretion of TNF-α (p<0.01, n=9-11) and nitric oxide (p<0.01, n=9) was impaired in Fosl-2 tg peritoneal macrophages compared to wt cells after LPS stimulation. Peritoneal macrophages were analyzed directly after isolation for macrophage polarization cell surface marker expression. Fosl-2 tg peritoneal macrophages showed an increase in the F4/80+CD11b+PD-L2+CD36+ cell population (p<0.01, n=3-6) compared to peritoneal macrophages from wt mice.The expression of cell surface markers of non-polarized and IL-4 stimulated SSc hMDM (n=17) showed an increased percentage of CD40+CD86+CD206+PD-L2+CD163+ cells (p<0.05) compared to healthy control hMDM (n=7). Phagocytic activity was enhanced in SSc hMDM (n=7) compared to healthy untreated (p<0.05), LPS (p=0.05) and IL-4 (p<0.05) hMDM (n=5).Conclusion:Our animal data indicates a role of Fosl-2 in regulating macrophage polarization with a shift from a classically-activated to an alternatively-activated phenotype. Similarly, SSc hMDM resemble a functional M(IL-4) alternative macrophage phenotype.Thus, maintaining a balanced proportion of classically- and alternatively-activated macrophage phenotypes may be an effective tool to control macrophage function in SSc.References:[1]Moreno-Moral, A., et al., Changes in macrophage transcriptome associate with systemic sclerosis and mediate GSDMA contribution to disease risk. Ann Rheum Dis, 2018. 77(4): p. 596-601.[2]Kania, G., M. Rudnik, and O. Distler, Involvement of the myeloid cell compartment in fibrogenesis and systemic sclerosis. Nat Rev Rheumatol, 2019. 15(5): p. 288-302.Disclosure of Interests:Amela Hukara: None declared, Michal Rudnik: None declared, Chantal Brigitta Rufer: None declared, Oliver Distler Speakers bureau: Actelion, Bayer, Boehringer Ingelheim, Medscape, Novartis, Roche, Menarini, Mepha, MSD, iQone, Pfizer, Consultant of: Abbvie, Actelion, Acceleron Pharma, Amgen, AnaMar, Arxx Therapeutics, Bayer, Baecon Discovery, Blade Therapeutics, Boehringer, CSL Behring, ChemomAb, Corpuspharma, Curzion Pharmaceuticals, Ergonex, Galapagos NV, GSK, Glenmark Pharmaceuticals, Inventiva, Italfarmaco, iQvia, Kymera, Medac, Medscape, Mitsubishi Tanabe Pharma, MSD, Roche, Sanofi, UCB, Lilly, Target BioScience, Pfizer, Grant/research support from: Actelion, Bayer, Boehringer Ingelheim, Kymera Therapeutics, Mitsubishi Tanabe, Przemyslaw Blyszczuk: None declared, Gabriela Kania: None declared

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Behҫet’s Disease, and the Role of TNF-α and TNF-α Blockers

International Journal of Molecular Sciences ◽

10.3390/ijms21093072 ◽

2020 ◽

Vol 21 (9) ◽

pp. 3072

Author(s):

Tim van der Houwen ◽

Jan van Laar

Keyword(s):

Systematic Review ◽

Course Of Disease ◽

Th22 Cells ◽

Cochrane Database ◽

Tnf Α ◽

Auto Inflammatory Disease ◽

Effect Of Treatment ◽

Ifn Γ ◽

Positive Effect

In this both narrative and systematic review, we explore the role of TNF-α in the immunopathogenesis of Behçet’s disease (BD) and the effect of treatment with TNF-α blockers. BD is an auto-inflammatory disease, characterized by recurrent painful oral ulcerations. The pathogenesis of BD is not yet elucidated; it is assumed that TNF-α may play a key role. In the narrative review, we report an increased production of TNF-α, which may be stimulated via TLR-signaling, or triggered by increased levels of IL-1β and IFN-γ. The abundance of TNF-α is found in both serum and in sites of inflammation. This increased presence of TNF-α stimulates T-cell development toward pro-inflammatory subsets, such as Th17 and Th22 cells. Treatment directed against the surplus of TNF-α is investigated in the systematic review, performed according to the PRISMA guideline. We searched the Pubmed and Cochrane database, including comparative studies only. After including 11 studies, we report a beneficial effect of treatment with TNF-α blockers on the various manifestations of BD. In conclusion, the pivotal role of TNF-α in the immunopathogenesis of BD is reflected in both the evidence of their pro-inflammatory effects in BD and in the evidence of the positive effect of treatment on the course of disease in BD.

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IL-36R ligands are potent regulators of dendritic and T cells

Blood ◽

10.1182/blood-2011-05-356873 ◽

2011 ◽

Vol 118 (22) ◽

pp. 5813-5823 ◽

Cited By ~ 177

Author(s):

Solenne Vigne ◽

Gaby Palmer ◽

Céline Lamacchia ◽

Praxedis Martin ◽

Dominique Talabot-Ayer ◽

...

Keyword(s):

T Cells ◽

Mhc Class Ii ◽

Critical Role ◽

T Helper ◽

Innate And Adaptive Immunity ◽

Murine Bone Marrow ◽

Intracellular Signals ◽

Tnf Α ◽

Ifn Γ

Abstract IL-36α (IL-1F6), IL-36β (IL-1F8), and IL-36γ (IL-1F9) are members of the IL-1 family of cytokines. These cytokines bind to IL-36R (IL-1Rrp2) and IL-1RAcP, activating similar intracellular signals as IL-1, whereas IL-36Ra (IL-1F5) acts as an IL-36R antagonist (IL-36Ra). In this study, we show that both murine bone marrow-derived dendritic cells (BMDCs) and CD4+ T lymphocytes constitutively express IL-36R and respond to IL-36α, IL-36β, and IL-36γ. IL-36 induced the production of proinflammatory cytokines, including IL-12, IL-1β, IL-6, TNF-α, and IL-23 by BMDCs with a more potent stimulatory effect than that of other IL-1 cytokines. In addition, IL-36β enhanced the expression of CD80, CD86, and MHC class II by BMDCs. IL-36 also induced the production of IFN-γ, IL-4, and IL-17 by CD4+ T cells and cultured splenocytes. These stimulatory effects were antagonized by IL-36Ra when used in 100- to 1000-fold molar excess. The immunization of mice with IL-36β significantly and specifically promoted Th1 responses. Our data thus indicate a critical role of IL-36R ligands in the interface between innate and adaptive immunity, leading to the stimulation of T helper responses.

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Polyphenols: From Theory to Practice

Foods ◽

10.3390/foods10112595 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2595

Author(s):

Alberto Bertelli ◽

Marco Biagi ◽

Maddalena Corsini ◽

Giulia Baini ◽

Giorgio Cappellucci ◽

...

Keyword(s):

Matrix Effect ◽

Virgin Olive Oil ◽

Extra Virgin Olive Oil ◽

Biological Properties ◽

Health Claims ◽

In Vitro Tests ◽

The Matrix ◽

Gender Characteristics

Background: The importance of polyphenols in human health is well known; these compounds are common in foods, such as fruits, vegetables, spices, extra virgin olive oil and wine. On the other hand, the different factors that modulate the biological activity of these compounds are less well known. Conceptualization of the work: In this review we took into account about 200 relevant and recent papers on the following topics: “polyphenols bioavailability”, “polyphenols matrix effect”, “food matrix effect”, “polyphenols-cytochromes interaction”, after having reviewed and updated information on chemical classification and main biological properties of polyphenols, such as the antioxidant, anti-radical and anti-inflammatory activity, together with the tricky link between in vitro tests and clinical trials. Key findings: the issue of polyphenols bioavailability and matrix effect should be better taken into account when health claims are referred to polyphenols, thus considering the matrix effect, enzymatic interactions, reactions with other foods or genetic or gender characteristics that could interfere. We also discovered that in vitro studies often underrate the role of phytocomplexes and thus we provided practical hints to describe a clearer way to approach an investigation on polyphenols for a more resounding transfer to their use in medicine.

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Role of Cannabidiol and Tetrahydrocannabivarin on Paclitaxel-Induced Neuropathic Pain in Rodents

10.21203/rs.3.rs-1189466/v1 ◽

2021 ◽

Author(s):

Anil Kumar Kalvala ◽

Arvind Bagde ◽

Peggy Arthur ◽

Sunil Kumar Surapaneni ◽

Ramesh Nimma ◽

...

Keyword(s):

Primary Cultures ◽

P38 Map Kinase ◽

Control Group ◽

Cb1 Receptors ◽

Neuroprotective Effects ◽

Sd Rats ◽

Protein Expressions ◽

Behavioral Parameters ◽

Neurobehavioral Symptoms

Abstract The purpose of this study was to investigate the neuroprotective effects of phytocannabinoids, synthetic cannabidiol (CBD) and tetrahydrocannabivarin (THCV) and their combination on taxol induced peripheral neuropathy (PIPN) in mice. Briefly, six groups of C57BL/6J mice (n = 6) were used. PTX (8 mg/kg/day, i.p.) was given to the mice on days 1, 3, 5, and 7 to induce neuropathy. Mice were evaluated for their behavioral parameters and also at the end of the study, DRG collected from the animals were subjected to RNA sequence and westernblot analysis. Further, immunocytochemistry and mitochondrial functional assays were performed on cultured DRGs derived from SD rats. The combination of CBD and THCV improved thermal and mechanical neurobehavioral symptoms in mice by two folds as compared to individual treatments. KEGG (RNA Sequencing) identified P38-MAPK, AMPK, and PI3K-AKT pathways as potential CBD and THCV therapeutic targets. In PTX-treated animals, the expression of p-AMPK, SIRT1, NRF2, HO1, SOD2, and catalase was significantly reduced (p<0.001), whereas the expression of PI3K, p-AKT, p-P38 MAP kinase, BAX, TGF-, NLRP3 inflammasome, and caspase 3 was significantly increased (p<0.001) when compared to control group. In reversing these protein expressions, combination therapy outperformed single therapies. CBD and THCV treatment increased AMPK, Catalase, and Complex I expression while decreasing mitochondrial superoxides in DRG primary cultures. In mice and DRG primary cultures, WAY100135 and rimonabant inhibited the effects of CBD and THCV by blocking 5 HT1A and CB1 receptors. In conclusion, entourage effect of CBD and THCV combination against PIPN appears to protect neurons in mice by modulating 5HT1A and CB1 receptors, respectively.

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Veiled Extra Virgin Olive Oils: Role of Emulsion, Water and Antioxidants

Colloids and Interfaces ◽

10.3390/colloids4030038 ◽

2020 ◽

Vol 4 (3) ◽

pp. 38

Author(s):

Giuseppe Cinelli ◽

Martina Cofelice ◽

Francesco Venditti

Keyword(s):

Olive Oil ◽

Current Knowledge ◽

Virgin Olive Oil ◽

Extra Virgin Olive Oil ◽

Bioactive Molecules ◽

Dispersed Phase ◽

Colloidal System ◽

Oil Processing

This review traces the current knowledge on the effects of various factors and phenomena that occur at interface, and the role of dispersed phase on the physicochemical, sensorial and nutritional characteristics of veiled extra virgin olive oil (VVOO). Since 1994 there have been numerous articles in the literature regarding the peculiar characteristic of unfiltered olive oil, so-called veiled or cloud virgin olive oil. It is a colloidal system (emulsion–sol), where the continuous lipidic phase dispreads mini droplets of milling water, fragments of cells and biotic fraction obtained from oil processing. During storage, the dispersed phase collapses and determines the quality of the virgin olive oil (VOO). The observed phenomena lead to worsening the quality of the product by causing defects such as oxidation of phenols, triacylglycerols hydrolysis and off-flavor formation. The addition of bioactive compounds, such as vitamins, on product based on VVOO, must take into account the eventual synergistic effect of individual substances. The role of the interphase is crucial to the synergic activity of bioactive molecules in improving oxidative stability, sensorial and health characteristics of VVOO.

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Pulmonary Inflammation Induced by Pseudomonas aeruginosa Lipopolysaccharide, Phospholipase C, and Exotoxin A: Role of Interferon Regulatory Factor 1

Infection and Immunity ◽

10.1128/iai.70.3.1352-1358.2002 ◽

2002 ◽

Vol 70 (3) ◽

pp. 1352-1358 ◽

Cited By ~ 49

Author(s):

Catharina W. Wieland ◽

Britta Siegmund ◽

Giorgio Senaldi ◽

Michael L. Vasil ◽

Charles A. Dinarello ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Pulmonary Inflammation ◽

Interferon Regulatory Factor ◽

Cell Infiltration ◽

Exotoxin A ◽

Regulatory Factor ◽

Interferon Regulatory Factor 1 ◽

Tnf Α ◽

Ifn Γ

ABSTRACT Chronic pulmonary infection with Pseudomonas aeruginosa is common in cystic fibrosis (CF) patients. P. aeruginosa lipopolysaccharide (LPS), phosholipase C (PLC), and exotoxin A (ETA) were evaluated for their ability to induce pulmonary inflammation in mice following intranasal inoculation. Both LPS and PLC induced high levels of tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), IL-6, gamma interferon (IFN-γ), MIP-1α and MIP-2 in the lungs but did not affect IL-18 levels. ETA did not induce TNF-α and was a weak inducer of IL-1β, IL-6, macrophage inflammatory protein 1α (MIP-1α), and MIP-2. Remarkably, ETA reduced constitutive lung IL-18 levels. LPS was the only factor inducing IFN-γ. LPS, PLC, and ETA all induced cell infiltration in the lungs. The role of interferon regulatory factor-1 (IRF-1) in pulmonary inflammation induced by LPS, PLC, and ETA was evaluated. When inoculated with LPS, IRF-1 gene knockout (IRF-1 KO) mice produced lower levels of TNF-α, IL-1β, and IFN-γ than did wild-type (WT) mice. Similarly, a milder effect of ETA on IL-1β and IL-18 was observed for IRF-1 KO than for WT mice. In contrast, the cytokine response to PLC did not differ between WT and IRF-1 KO mice. Accordingly, LPS and ETA, but not PLC, induced expression of IRF-1 mRNA. IRF-1 deficiency had no effect on MIP-1α and MIP-2 levels and on cell infiltration induced by LPS, PLC, or ETA. Flow cytometric evaluation of lung mononuclear cells revealed strongly reduced percentages of CD8+ and NK cells in IRF-1 KO mice compared to percentages observed for WT mice. These data indicate that different virulence factors from P. aeruginosa induce pulmonary inflammation in vivo and that IRF-1 is involved in some of the cytokine responses to LPS and ETA.

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