scholarly journals Defense and protection mechanisms in lung exposed to asbestiform fiber: the role of macrophage migration inhibitory factor and heme oxygenase-1

2020 ◽  
Vol 64 (2) ◽  
Author(s):  
Carla Loreto ◽  
Rosario Caltabiano ◽  
Adriana Carol Eleonora Graziano ◽  
Sergio Castorina ◽  
Claudia Lombardo ◽  
...  

Fluoro-edenite (FE), an asbestiform fiber, is responsible for many respiratory pathologies: chronic obstructive diseases, pleural plaques, fibrosis, and malignant mesothelioma. Macrophage migration inhibitory factor (MIF) is one of the first cytokines produced in response to lung tissue damage. Heme oxygenase-1 (HO-1) is a protein with protective effects against oxidative stress. It is up regulated by several stimuli including pro-inflammatory cytokines and factors that promote oxidative stress. In this research, the in vivo model of sheep lungs naturally exposed to FE was studied in order to shed light on the pathophysiological events sustaining exposure to fibers, by determining immunohistochemical lung expression of MIF and HO-1. Protein levels expression of HO-1 and MIF were also evaluated in human primary lung fibroblasts after exposure to FE fibers in vitro. In exposed sheep lungs, MIF and HO-1 immunoexpression were spread involving the intraparenchymal stroma around bronchioles, interstitium between alveoli, alveolar epithelium and macrophages. High MIF immunoexpression prevails in macrophages. Similar results were obtained in vitro, but significantly higher values were only detected for HO-1 at concentrations of 50 and 100 μg/mL of FE fibers. MIF and HO-1 expressions seem to play a role in lung self-protection against uncontrolled chronic inflammation, thus counteracting the strong link with cancer development, induced by exposure to FE. Further studies will be conducted in order to add more information about the role of MIF and HO-1 in the toxicity FE-induced.

Author(s):  
Theresa Wirtz ◽  
Alena Saal ◽  
Irina Bergmann ◽  
Petra Fischer ◽  
Daniel Heinrichs ◽  
...  

Background and Purpose: Macrophage migration inhibitory factor (MIF) is an inflammatory and chemokine-like protein expressed in different diseases as well as solid tumours. Here, CD74 – as the cognate MIF receptor – was identified as an important target of MIF. We analysed the role of MIF and CD74 in the progression of hepatocellular carcinoma (HCC) in vitro and in vivo using an experimental murine HCC model. Experimental Approach: Multilocular HCC was induced using the diethylnitrosamine/carbon tetrachloride (DEN/CCl4) model in hepatocyte-specific Mif knockout (Mif Δhep), CD74-deficient, and control mice. Tumour burden was compared between the genotypes. MIF, CD74 and Ki67 expression were investigated in tumour and surrounding tissue. In vitro, the impact of the MIF/CD74 axis on the proliferative and apoptotic behaviour of hepatoma cells was assessed after stimulation with MIF and anti-CD74 antibodies. Key Results: DEN/CCl4 treatment of Mif Δhep mice resulted in reduced tumour burden and diminished proliferation capacity within the tumour tissue. In vitro, MIF stimulated the proliferation of Hepa 1-6 cells and inhibited therapy-induced cell death as evidenced by TUNEL-staining. Both effects could be reversed using a neutralizing anti-CD74 antibody, and Cd74-/- mice developed fewer tumours associated with decreased proliferation rates. Conclusion and Implications: In this study, we identified a pro-tumorigenic role of MIF during proliferation and therapy-induced apoptosis of HCC cells. Furthermore, our study implicates that these effects are mediated via the MIF cognate receptor CD74. In conclusion, the inhibition of the MIF/CD74 axis could present a promising target with regard to prospective HCC-directed pharmacological therapies.


2010 ◽  
Vol 78 (12) ◽  
pp. 5151-5162 ◽  
Author(s):  
Swati Thorat ◽  
Thomas M. Daly ◽  
Lawrence W. Bergman ◽  
James M. Burns

ABSTRACT The excessive production of proinflammatory cytokines plays a significant role in the pathogenesis of severe malaria. Mammalian macrophage migration inhibitory factor (MIF) (mMIF) is an immune mediator that promotes a sustained proinflammatory response by inhibiting the glucocorticoid-mediated downregulation of inflammation. In addition, Plasmodium parasites also encode a homologue of mammalian MIF that is expressed in asexual-stage parasites. We used the Plasmodium yoelii murine model to study the potential role of parasite-encoded MIF in the pathogenesis of malaria. Antibodies raised against purified, non-epitope-tagged P. yoelii MIF (PyMIF) were used to localize expression in trophozoite- and schizont-stage parasites and demonstrate extracellular release. In vitro, recombinant PyMIF was shown to actively induce the chemotaxis of macrophages but did not induce or enhance tumor necrosis factor alpha (TNF-α) production from peritoneal macrophages. To examine the role of parasite-derived PyMIF in vivo, two transgenic parasite lines that constitutively overexpress PyMIF were generated, one in a nonlethal P. yoelii 17X background [Py17X-MIF(+)] and the other in a lethal P. yoelii 17XL background [Py17XL-MIF(+)]. Challenge studies with transgenic parasites in mice showed that the increased expression of PyMIF resulted in a reduction in disease severity. Mice infected with Py17X-MIF(+) developed lower peak parasitemia levels than controls, while malaria-associated anemia was unaltered. Infection with Py17XL-MIF(+) resulted in a prolonged course of infection and a reduction in the overall mortality rate. Combined, the data indicate that parasite-derived MIF does not contribute significantly to immunopathology but, through its chemotactic ability toward macrophages, may attenuate disease and prolong infection of highly virulent parasite isolates.


Biomolecules ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 38 ◽  
Author(s):  
Svenja Voss ◽  
Saskia Krüger ◽  
Katharina Scherschel ◽  
Svenja Warnke ◽  
Michael Schwarzl ◽  
...  

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine known to play a major role in inflammatory diseases such as myocardial infarction (MI), where its expression increases. Cardio protective functions of MIF during ischemia have been reported. Recently, the structurally related MIF-2 was identified and similar effects are assumed. We wanted to further investigate the role of MIF and MIF-2 on inflammatory processes during MI. Therefore, we subjected mice to experimentally induced MI by coronary occlusion for one and five days. During the acute phase of MI, the gene expression of Mif was upregulated in the infarct zone, whereas Mif-2 was downregulated, suggesting a minor role of MIF-2. Simulating ischemic conditions or mechanical stress in vitro, we demonstrated that Mif expression was induced in resident cardiac cells. To investigate possible auto /paracrine effects, cardiomyocytes and cardiac fibroblasts were individually treated with recombinant murine MIF, which in turn induced Mif expression and the expression of pro-inflammatory genes in cardiac fibroblasts. Cardiomyocytes did not respond to recombinant MIF with pro-inflammatory gene expression. While MIF stimulation alone did not change the expression of pro-fibrotic genes in cardiac fibroblasts, ischemia reduced their expression. Mimicking the increased MIF levels during MI, we exposed cardiac fibroblasts to simulated ischemia in the presence of MIF, which led to further reduced expression of pro-fibrotic genes. The presented data show that MIF was expressed by resident cardiac cells during MI. In vitro, Mif expression was induced by different external stimuli in cardiomyocytes and cardiac fibroblasts. Addition of recombinant MIF protein increased the expression of pro-inflammatory genes in cardiac fibroblasts including Mif expression itself. Thereby, cardiac fibroblasts may amplify Mif expression during ischemia promoting cardiomyocyte survival.


2007 ◽  
Vol 292 (1) ◽  
pp. E272-E280 ◽  
Author(s):  
Francesca Ietta ◽  
Yuanhong Wu ◽  
Roberta Romagnoli ◽  
Nima Soleymanlou ◽  
Barbara Orsini ◽  
...  

Macrophage migration inhibitory factor (MIF) is an important proinflammatory cytokine involved in regulation of macrophage function. In addition, MIF may also play a role in murine and human reproduction. Although both first trimester trophoblast and decidua express MIF, the regulation and functional significance of this cytokine during human placental development remains unclear. We assessed MIF expression throughout normal human placental development, as well as in in vitro (chorionic villous explants) and in vivo (high altitude placentae) models of human placental hypoxia. Dimethyloxalylglycine (DMOG), which stabilizes hypoxia inducible factor-1 under normoxic conditions, was also used to mimic the effects of hypoxia on MIF expression. Quantitative real-time PCR and Western blot analysis showed high MIF protein and mRNA expression at 7–10 wk and lower levels at 11–12 wk until term. Exposure of villous explants to 3% O2 resulted in increased MIF expression and secretion relative to standard conditions (20% O2). DMOG treatment under 20% O2 increased MIF expression. In situ hybridization and immunohistochemistry showed elevated MIF expression in low oxygen-induced extravillous trophoblast cells. Finally, a significant increase in MIF transcript was observed in placental tissues from high-altitude pregnancies. Hence, three experimental models of placental hypoxia (early gestation, DMOG treatment, and high altitude) converge in stimulating increased MIF, supporting the conclusion that placental-derived MIF is an oxygen-responsive cytokine highly expressed in physiological in vivo and in in vitro low oxygen conditions.


2012 ◽  
Vol 189 (8) ◽  
pp. 3905-3913 ◽  
Author(s):  
Susanna Choi ◽  
Hang-Rae Kim ◽  
Lin Leng ◽  
Insoo Kang ◽  
William L. Jorgensen ◽  
...  

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