Liliana Marques1, Anne Negre-Salvayre2, Luciana Costa3, François Canonne-Hergaux4. 1. INSERM UMR 1043, CNRS UMR 5282, Université de Toulouse, UPS, Centre de Physiopathologie de Toulouse Purpan (CPTP), Toulouse, France; Departamento da Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal. 2. INSERM UMR 1048 I2MC, Université de Toulouse, Toulouse, France. 3. Departamento da Promoção da Saúde e Prevenção de Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal. Electronic address: luciana.costa@insa.min-saude.pt. 4. INSERM UMR 1043, CNRS UMR 5282, Université de Toulouse, UPS, Centre de Physiopathologie de Toulouse Purpan (CPTP), Toulouse, France; IRSD, Université de Toulouse, INSERM, INRA, INP-ENVT, Université de Toulouse 3 Paul Sabatier, Toulouse, France. Electronic address: francois.canonne-hergaux@inserm.fr.
Abstract
RATIONALE: The role of macrophage iron in the physiopathology of atherosclerosis is an open question that needs to be clarified. In atherosclerotic lesions, recruited macrophages are submitted to cytokines and oxidized lipids which influence their phenotype. An important phenotypic population driven by oxidized phospholipids is the Mox macrophages which present unique biological properties but their iron phenotype is not well described. OBJECTIVE: To investigate the effect of Mox polarization by oxidized LDL (oxLDL) on macrophage iron metabolism in the absence or presence of proinflammatory stimuli. METHODS: Bone marrow-derived macrophages were treated with different sources of LDL and/or LPS/IFNγ (M1 activator). Expression of ferroportin (Slc40a1, alias Fpn), heme oxygenase-1 (Hmox1), H- and L-ferritin (Fth1 and Ftl1), hepcidin (Hamp), ceruloplasmin (Cp) and interleukine-6 (Il6) was followed by quantitative PCR. FPN and HMOX1 protein expression was analyzed by immunofluorescence and in-cell-Western blotting. RESULTS: Mox macrophages expressed increased Hmox1 and Fth1 levels with basal FPN protein levels despite the significant increase of Fpn mRNA. Upregulation of Hmox1 and Fpn mRNA was specific to LDL oxidative modification and mediated by NRF2. The downregulation of both Cp isoforms and the upregulation of Hamp expression observed in Mox macrophages suggest that FPN mediated iron export could be compromised. Simultaneous exposure to oxLDL and LPS/IFNγ leads to a mixed Mox/M1 phenotype that is closer to M1. CONCLUSION: A microenvironment rich in oxLDL and proinflammatory cytokines could promote macrophage iron retention and lipid accumulation profiles, a specific cell phenotype that likely contributes to lesion development and plaque instability in atherosclerosis.
RATIONALE: The role of macrophage iron in the physiopathology of atherosclerosis is an open question that needs to be clarified. In atherosclerotic lesions, recruited macrophages are submitted to cytokines and oxidized lipids which influence their phenotype. An important phenotypic population driven by oxidized phospholipids is the Mox macrophages which present unique biological properties but their iron phenotype is not well described. OBJECTIVE: To investigate the effect of Mox polarization by oxidized LDL (oxLDL) on macrophage iron metabolism in the absence or presence of proinflammatory stimuli. METHODS: Bone marrow-derived macrophages were treated with different sources of LDL and/or LPS/IFNγ (M1 activator). Expression of ferroportin (Slc40a1, alias Fpn), heme oxygenase-1 (Hmox1), H- and L-ferritin (Fth1 and Ftl1), hepcidin (Hamp), ceruloplasmin (Cp) and interleukine-6 (Il6) was followed by quantitative PCR. FPN and HMOX1 protein expression was analyzed by immunofluorescence and in-cell-Western blotting. RESULTS:Mox macrophages expressed increased Hmox1 and Fth1 levels with basal FPN protein levels despite the significant increase of Fpn mRNA. Upregulation of Hmox1 and Fpn mRNA was specific to LDL oxidative modification and mediated by NRF2. The downregulation of both Cp isoforms and the upregulation of Hamp expression observed in Mox macrophages suggest that FPN mediated iron export could be compromised. Simultaneous exposure to oxLDL and LPS/IFNγ leads to a mixed Mox/M1 phenotype that is closer to M1. CONCLUSION: A microenvironment rich in oxLDL and proinflammatory cytokines could promote macrophage iron retention and lipid accumulation profiles, a specific cell phenotype that likely contributes to lesion development and plaque instability in atherosclerosis.
Authors: Katalin Kis-Toth; Gaurav Manohar Rajani; Allison Simpson; Kate L Henry; Jennifer Dumont; Robert T Peters; Joe Salas; Christine Loh Journal: Blood Adv Date: 2018-11-13
Authors: Jorge Rodrigues de Sousa; Pedro Fernando Da Costa Vasconcelos; Juarez Antonio Simões Quaresma Journal: Infect Drug Resist Date: 2019-08-22 Impact factor: 4.003
Authors: Marieli Gonzalez-Cotto; Liang Guo; Megan Karwan; Shurjo K Sen; Jennifer Barb; Carlos J Collado; Fathi Elloumi; Erika M Palmieri; Kimberly Boelte; Frank D Kolodgie; Aloke V Finn; Leslie G Biesecker; Daniel W McVicar Journal: Front Immunol Date: 2020-03-30 Impact factor: 7.561