Anti-inflammatory Polarization Research Articles

Yerba Mate (Ilex Paraguariensis) Reduces Colitis Severity by Promoting Anti-Inflammatory Macrophage Polarization

Yerba Mate (Ilex Paraguariensis) Reduces Colitis Severity by Promoting Anti-Inflammatory Macrophage Polarization

Lipopolysaccharide pretreatment increases the sensitivity of the TRPV1 channel and promotes an anti-inflammatory phenotype of capsaicin-activated macrophages

BackgroundThe transient receptor potential vanilloid 1 (TRPV1) is well-established in neuronal function, yet its role in immune reactions remains enigmatic. The conflicting data on its inflammatory role, suggesting both pro-inflammatory and anti-inflammatory effects upon TRPV1 stimulation in immune cells, adds complexity. To unravel TRPV1 immunomodulatory mechanisms, we investigated how the TRPV1 agonist capsaicin influences lipopolysaccharide (LPS)-induced pro-inflammatory macrophage phenotypes.ResultsChanges in the surface molecules, cytokine production, and signaling cascades linked to the phenotype of M1 or M2 macrophages of the J774 macrophage cell line and bone marrow-derived macrophages, treated with capsaicin before or after the LPS-induced inflammatory reaction were determined. The functional capacity of macrophages was also assessed by infecting the stimulated macrophages with the intracellular parasite Leishmania mexicana.ConclusionOur findings reveal that TRPV1 activation yields distinct macrophage responses influenced by the inflammatory context. LPS pre-treatment followed by capsaicin activation prompted increased calcium influx, accompanied by a shift toward an anti-inflammatory M2b-like polarization state.

Mechanical stretch preconditioned adipose-derived stem cells elicit polarization of anti-inflammatory M2-like macrophages and improve chronic wound healing.

Transplantation of adipose-derived stem cells (ASCs) is a promising option in the field of chronic wounds treatment. However, the effectiveness of ASCs therapies has been hampered by highly inflammatory environment in chronic wound areas. These problems could be partially circumvented using efficient approaches that boost the survival and anti-inflammatory capacity of transplanted ASCs. Here, by application of mechanical stretch (MS), we show that ASCs exhibits increased survival and immunoregulatory properties invitro. MS triggers the secretion of macrophage colony stimulating factor (M-CSF) from ASCs, a chemokine that is linked to anti-inflammatory M2-like macrophages polarization. When the MS-ASCs were transplanted to chronic wounds, the wound area yields significantly faster closure rate and lower inflammatory mediators, largely due to macrophages polarization driven by transplanted MS-ASCs. Thus, our work shows that mechanical stretch can be harnessed to enhance ASCs transplantation efficiency in chronic wounds treatment.

E4BP4 in macrophages induces an anti-inflammatory phenotype that ameliorates the severity of colitis

Macrophages are versatile cells of the innate immune system that work by altering their pro- or anti-inflammatory features. Their dysregulation leads to inflammatory disorders such as inflammatory bowel disease. We show that macrophage-specific upregulation of the clock output gene and transcription factor E4BP4 reduces the severity of colitis in mice. RNA-sequencing and single-cell analyses of macrophages revealed that increased expression of E4BP4 leads to an overall increase in expression of anti-inflammatory genes including Il4ra with a concomitant reduction in pro-inflammatory gene expression. In contrast, knockout of E4BP4 in macrophages leads to increased proinflammatory gene expression and decreased expression of anti-inflammatory genes. ChIP-seq and ATAC-seq analyses further identified Il4ra as a target of E4BP4, which drives anti-inflammatory polarization in macrophages. Together, these results reveal a critical role for E4BP4 in regulating macrophage inflammatory phenotypes and resolving inflammatory bowel diseases.

Gadolinium retention effect on macrophages - a potential cause of MRI contrast agent Dotarem toxicity.

Gadolinium is a component of the MRI contrast agent Dotarem. Although Dotarem is the least toxic among MRI contrasts used, gadolinium present in Dotarem accumulates for many years in various organs and tissues exerting toxic effects. We showed previously that gadolinium remains in macrophages for at least 7days after exposure to Dotarem. However, very little is known about the effect of gadolinium retention on the immune cells such as macrophages. We studied the effect of 1-day and 7-day retention of gadolinium on various functions and molecular pathways of macrophages. Gadolinium retention for 7days decreased macrophage adhesion and motility and dysregulated the expression of adhesion and fibrotic pathway-related proteins such as Notch1 and its ligand Jagged1, adhesion/migration-related proteins PAK1 and Shp1, immune response-related transcription factors Smad3 and TCF19, and chemokines CXCL10 and CXCL13, and dysregulated the mRNA expression of fibrosis-related genes involved in extracellular matrix (ECM) synthesis, such as Col6a1, Fibronectin, MMP9, and MMP12. It also completely (below a level of detection) shut down the transcription of anti-inflammatory M2 macrophage polarization marker theArg-1.Such changes, if they occur in MRI patients, can be potentially detrimental to the patient's immune system and immune response-related processes.

Targeting the aryl hydrocarbon receptor with FICZ regulates IL-2 and immune infiltration to alleviate Hashimoto's thyroiditis in mice

Hashimoto's thyroiditis (HT) is the most frequent autoimmune disorder. Growing work points to the involvement of aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, in the regulation of immune homeostasis. However, the roles of AhR and its ligands in HT remains unclear. In this study, we leveraged public human database analyses to postulate that the AhR expression was predominantly in thyroid follicular cells, correlating significantly with the thyroid infiltration levels of multiple immune cells in HT patients. Using a thyroglobulin-induced HT mouse model and in vitro thyroid follicular epithelial cell cultures, we found a significant downregulation of AhR expression in thyrocytes both in vivo and in vitro. Conversely, activating AhR by FICZ, a natural AhR ligand, mitigated inflammation and apoptosis in thyrocytes in vitro and conferred protection against HT in mice. RNA sequencing (RNA-seq) of thyroid tissues indicated that AhR activation moderated HT-associated immune or inflammatory signatures. Further, immunoinfiltration analysis indicated that AhR activation regulated immune cell infiltration in the thyroid of HT mice, such as suppressing cytotoxic CD8+ T cell infiltration and promoting anti-inflammatory M2 macrophage polarization. Concomitantly, the expression levels of interleukin-2 (IL-2), a lymphokine that downregulates immune responses, were typically decreased in HT but restored upon AhR activation. In silico validation substantiated the binding interaction between AhR and IL-2. In conclusion, targeting the AhR with FICZ regulates IL-2 and immune infiltration to alleviate experimental HT, shedding new light on the therapeutic intervention of this prevalent disease.

MFGE8 in exosomes derived from mesenchymal stem cells prevents esophageal stricture after endoscopic submucosal dissection in pigs

BackgroundEndoscopic submucosal dissection (ESD) is the current standard treatment for early-stage esophageal neoplasms. However, the postoperative esophageal stricture after extensive mucosal dissection remains a severe challenge with limited effective treatments available. In this study, we introduced a chitosan/gelatin (ChGel) sponge encapsulating the adipose mesenchymal stem cells (ADMSCs)-derived exosomes (ChGelMSC−Exo) for the prevention of esophageal stenosis after ESD in a porcine model.ResultsPigs were randomly assigned into (1) ChGelMSC−Exo treatment group, (2) ChGelPBS group, and (3) the controls. Exosome treatments were applied immediately on the day after ESD as well as on day 7. Exosome components crucial for wound healing were investigated by liquid chromatography-tandem mass spectrometry (LC–MS/MS) and small RNA sequencing. ChGelMSC−Exo treatment significantly reduced mucosal contraction on day 21, with less fiber accumulation and inflammatory infiltration, and enhanced angiogenesis when compared with the control and ChGelPBS groups. The anti-fibrotic effects following MSC-Exo treatment were further found to be associated with the anti-inflammatory M2 polarization of the resident macrophages, especially within the M2b subset characterized by the reduced TGFβ1 secretion, which sufficiently inhibited inflammation and prevented the activation of myofibroblast with less collagen production at the early stage after ESD. Moreover, the abundant expression of exosomal MFGE8 was identified to be involved in the transition of the M2b-macrophage subset through the activation of MFGE8/STAT3/Arg1 axis.ConclusionsOur study demonstrates that exosomal MFGE8 significantly promotes the polarization of the M2b-macrophage subset, consequently reducing collagen deposition. These findings suggest a promising potential for MSC-Exo therapy in preventing the development of esophageal stricture after near-circumferential ESD.Graphical

Abstract 6873: Prognostic impact of squamous cell carcinoma antigen as a mediator of anti-inflammatory macrophage polarization in tumor microenvironment

Abstract Squamous cell carcinoma antigen 1 (SCCA1) is a potential biomarker and prognostic indicator for many epithelial cancers including cervix, head and neck, breast, and lung. Cancer patients with high serum levels of SCCA commonly experience treatment resistance and recurrence. We analyze SCCA expression in correlation with tumor microenvironment from 66 human cervical tumor biopsies and find that high serum SCCA is associated with increased macrophage infiltration in tumors and poor overall survival. In a single cell RNAseq analysis of 8 cervical tumors, patients with high SCCA1 show increased immunosuppressive genes (C1QA, C1QC, APOE) and reduced MHC molecules (HLA-DR, HLA-DQA1) in their tumor associated macrophages (TAMs), corresponding to decreased expression of T-cell cytotoxic-associated genes (IFNG, GZMB, PRF1). Thus, we aim to understand the impact of elevated SCCA1 on macrophages and its role in shaping the immune response. Co-culture of peritoneal macrophages isolated from SCCA1-treated mice with T cells from syngeneic wild-type mice, showed significant suppression in T cell proliferation. Downregulation of antigen presentation molecules was also observed SCCA1-treated macrophages and resulted in impaired ability to induce T cell activation by peptide-pulsed macrophages. Compared with treatment-naïve mice, SCCA1-treated macrophages showed increased anti-inflammatory cytokine CCL22, IL10 and immunosuppression regulators ARG1, PD-L1 expression. Moreover, human monocyte-derived M2 macrophages treated with SCCA1 during the differentiation process demonstrated inhibition toward CD3/28-induced T cell proliferation, accompanied by enhanced expression of cytokines, IL10 and CCL18. We further found that targeting SCCA1 by small interfering RNA knockdown significantly reduced tumor growth and macrophage infiltration, resulting in improved T-cell antitumor immunity. Lastly, analysis of cervical cancer patients with chemoradiation therapy showed that patients with high SCCA are associated with increased exhaustion (LAG3, CTLA4) and decreased antitumor gene signature (GZMB, IFNG) during treatment. In summary, SCCA expression promotes immunosuppressive macrophage polarization and function, contributing to T cell exhaustion phenotype and poor treatment response. Citation Format: Liyun Chen, Victoria Shi, Eric Liu, Jasmine Yang, Abhay Singh, Matthew Inkman, Jin Zhang, Julie Schwarz, Stephanie Markovina. Prognostic impact of squamous cell carcinoma antigen as a mediator of anti-inflammatory macrophage polarization in tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6873.

A sericin hydrogel scaffold for sustained dexamethasone release modulates macrophage polarization to promote mandibular bone defect repair in rats

To evaluate the efficacy of a modified sericin hydrogel scaffold loaded with dexamethasone (SMH-CD/DEX) scaffold for promoting bone defect healing by stimulating anti-inflammatory macrophage polarization. The light-curable SMH-CD/DEX scaffold was prepared using dexamethasone-loaded NH2-β-cyclodextrin (NH2-β-CD) and sericin hydrogel and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), biocompatibility assessment and drug release test. THP-1 macrophages incubated with the scaffold were examined for protein expressions of iNOS and Arg-1, mRNA expressions of IL-6, Il-10, Arg-1 and iNOS, and surface markers CD86 and CD206 using Western blotting, RT-qPCR, and flow cytometry. In a co-culture system of human periodontal ligament stem cells (HPDLSCs) and THP-1 macrophages, the osteogenic ability of the stem cells incubated with the scaffold was evaluated by detecting protein expressions of COL1A1 and Runx2 and expressions of ALP, Runx2, OCN and BMP2 mRNA, ALP staining, and alizarin red staining. In a rat model of mandibular bone defect, the osteogenic effect of the scaffold was assessed by observing bone regeneration using micro-CT and histopathological staining. In THP-1 macrophages, incubation with SMH-CD/DEX scaffold significantly enhanced protein expressions of Arg-1 and mRNA expressions of IL-10 and Arg-1 and lowered iNOS protein expression and IL-6 and iNOS mRNA expressions. In the co-culture system, SMH-CD/DEX effectively increased the protein expressions of COL1A1 and Runx2 and mRNA expressions of ALP and BMP2 in HPDLSCs and promoted their osteogenic differentiation. In the rat models, implantation of SMH-CD/DEX scaffold significantly promoted bone repair and bone regeneration in the bone defect. The SMH-CD/DEX scaffold capable of sustained dexamethasone release promotes osteogenic differentiation of stem cells and bone defect repair in rats by regulating M2 polarization.

Hepatitis B virus e antigen induces atypical metabolism and differentially regulates programmed cell deaths of macrophages.

Macrophages can undergo M1-like proinflammatory polarization with low oxidative phosphorylation (OXPHOS) and high glycolytic activities or M2-like anti-inflammatory polarization with the opposite metabolic activities. Here we show that M1-like macrophages induced by hepatitis B virus (HBV) display high OXPHOS and low glycolytic activities. This atypical metabolism induced by HBV attenuates the antiviral response of M1-like macrophages and is mediated by HBV e antigen (HBeAg), which induces death receptor 5 (DR5) via toll-like receptor 4 (TLR4) to induce death-associated protein 3 (DAP3). DAP3 then induces the expression of mitochondrial genes to promote OXPHOS. HBeAg also enhances the expression of glutaminases and increases the level of glutamate, which is converted to α-ketoglutarate, an important metabolic intermediate of the tricarboxylic acid cycle, to promote OXPHOS. The induction of DR5 by HBeAg leads to apoptosis of M1-like and M2-like macrophages, although HBeAg also induces pyroptosis of the former. These findings reveal novel activities of HBeAg, which can reprogram mitochondrial metabolism and trigger different programmed cell death responses of macrophages depending on their phenotypes to promote HBV persistence.

Decellularized amniotic membrane promotes the anti-inflammatory response of macrophages via PI3K/AKT/HIF-1α pathway

Macrophages undergo dynamic transitions between M1 and M2 states, exerting profound influences on both inflammatory and regenerative processes. The biocompatible and wound-healing properties of decellularized amniotic membrane (dAM) make it a subject of exploration for its potential impact on the anti-inflammatory response of macrophages. Experimental findings unequivocally demonstrate that dAM promotes anti-inflammatory M2 polarization of macrophage, with its cytokine-rich content posited as a potential mediator. The application of RNA sequencing unveils differential gene expression, implicating the hypoxia inducible factor-1α (HIF-1α) signaling pathway in this intricate interplay. Subsequent investigation further demonstrates that dAM facilitates anti-inflammatory M2 polarization of macrophage through the upregulation of epidermal growth factor (EGF), which, in turn, activates the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway and stabilizes HIF-1α. This cascade results in a noteworthy augmentation of anti-inflammatory gene expression. This study significantly contributes to advancing our comprehension of dAM's immunomodulatory role in tissue repair, thereby suggesting promising therapeutic potential.

Analysis of secreted small extracellular vesicles from activated human microglial cell lines reveals distinct pro- and anti-inflammatory proteomic profiles.

Microglia are a specialized population of innate immune cells located in the central nervous system. In response to physiological and pathological changes in their microenvironment, microglia can polarize into pro-inflammatory or anti-inflammatory phenotypes. A dysregulation in the pro-/anti-inflammatory balance is associated with many pathophysiological changes in the brain and nervous system. Therefore, the balance between microglia pro-/anti-inflammatory polarization can be a potential biomarker for the various brain pathologies. A non-invasive method of detecting microglia polarization in patients would have promising clinical applications. Here, we perform proteomic analysis of small extracellular vesicles (sEVs) derived from microglia cells to identify sEVs biomarkers indicative of pro-inflammatory and anti-inflammatory phenotypic changes. sEVs were isolated from microglia cell lines under different inflammatory conditions and analyzed by proteomics by liquid chromatography with mass spectrometry. Our findings provide the potential roles of sEVs that could be related to the pathogenesis of various brain diseases.

Azithromycin Augments Bacterial Uptake and Anti-Inflammatory Macrophage Polarization in Cystic Fibrosis.

Azithromycin (AZM) is widely being used for treating patients with cystic fibrosis (pwCF) following clinical trials demonstrating improved lung function and fewer incidents of pulmonary exacerba-tions. While the precise mechanisms remain elusive, immunomodulatory actions are thought to be involved. We previously reported impaired phagocytosis and defective anti-inflammatory M2 macrophage polarization in CF. This study systematically analyzed the effect of AZM on the functions of unpolarized and M1/M2 polarized macrophages in CF. Monocytes, isolated from the venous blood of patients with CF (pwCF) and healthy controls (HCs), were differentiated into monocyte-derived macrophages (MDMs) and subsequently infected with P. aeruginosa. P. aeruginosa uptake and killing by MDMs in the presence or absence of AZM was studied. M1 and M2 macrophage polarizations were induced and their functions and cytokine release were analyzed. Following AZM treatment, both HC and CF MDMs exhibited a significant increase in P. aeruginosa uptake and killing, however, lysosomal acidification remained unchanged. AZM treatment led to higher activation of ERK1/2 in both HC and CF MDMs. Pharmacological inhibition of ERK1/2 using U0126 significantly reduced P. aeruginosa uptake in HC MDMs. M1 macrophage polarization remained unaffected; however, AZM treatment led to increased IL-6 and IL-10 release in both HC and CF M1 macrophages. AZM also significantly increased the phagocytic index for both pHrodo E. coli and S. aureus in CF M1 macrophages. In CF, AZM treatment promoted anti-inflammatory M2 macrophage polarization, with an increased percentage of CD209+ M2 macrophages, induction of the M2 gene CCL18, along with its secretion in the culture supernatant. However, AZM d'd not restore endocytosis in CF, another essential feature of M2 macrophages. This study highlights the cellular functions and molecular targets of AZM which may involve an improved uptake of both Gram-positive and Gram-negative bacteria, restored anti-inflammatory macrophage polarization in CF. This may in turn shape the reduced lung inflammation observed in clinical trials. In addition, we confirmed the role of ERK1/2 activation for bacterial uptake.

CD147 Sparks Atherosclerosis by Driving M1 Phenotype and Impairing Efferocytosis.

Atherosclerosis is a globally prevalent chronic inflammatory disease with high morbidity and mortality. The development of atherosclerotic lesions is determined by macrophages. This study aimed to investigate the specific role of myeloid-derived CD147 (cluster of differentiation 147) in atherosclerosis and its translational significance. We generated mice with a myeloid-specific knockout of CD147 and mice with restricted CD147 overexpression, both in an apoE-deficient (ApoE-/-) background. Here, the myeloid-specific deletion of CD147 ameliorated atherosclerosis and inflammation. Consistent with our in vivo data, macrophages isolated from myeloid-specific CD147 knockout mice exhibited a phenotype shift from proinflammatory to anti-inflammatory macrophage polarization in response to lipopolysaccharide/IFN (interferon)-γ. These macrophages demonstrated a weakened proinflammatory macrophage phenotype, characterized by reduced production of NO and reactive nitrogen species derived from iNOS (inducible NO synthase). Mechanistically, the TRAF6 (tumor necrosis factor receptor-associated factor 6)-IKK (inhibitor of κB kinase)-IRF5 (IFN regulatory factor 5) signaling pathway was essential for the effect of CD147 on proinflammatory responses. Consistent with the reduced size of the necrotic core, myeloid-specific CD147 deficiency diminished the susceptibility of iNOS-mediated late apoptosis, accompanied by enhanced efferocytotic capacity mediated by increased secretion of GAS6 (growth arrest-specific 6) in proinflammatory macrophages. These findings were consistent in a mouse model with myeloid-restricted overexpression of CD147. Furthermore, we developed a new atherosclerosis model in ApoE-/- mice with humanized CD147 transgenic expression and demonstrated that the administration of an anti-human CD147 antibody effectively suppressed atherosclerosis by targeting inflammation and efferocytosis. Myeloid CD147 plays a crucial role in the growth of plaques by promoting inflammation in a TRAF6-IKK-IRF5-dependent manner and inhibiting efferocytosis by suppressing GAS6 during proinflammatory conditions. Consequently, the use of anti-human CD147 antibodies presents a complementary therapeutic approach to the existing lipid-lowering strategies for treating atherosclerotic diseases.

Biocatalytic nitric oxide generating hydrogels with enhanced anti-inflammatory, cell migration, and angiogenic capabilities for wound healing applications.

Although wound healing is a normal physiological process in the human body, it is often impaired by bacterial infections, ischemia, hypoxia, and excess inflammation, which can lead to chronic and non-healing wounds. Recently, injectable hydrogels with controlled nitric oxide (NO) release behaviour have become potential wound healing therapeutic agents due to their excellent biochemical, mechanical, and biological properties. Here, we proposed novel multifunctional NO-releasing hydrogels that could regulate various wound healing processes, including hemostasis, inflammation, cell proliferation and angiogenesis. By incorporating the copper nanoparticles (NPs) in the network of dual enzymatically crosslinked gelatin hydrogels (GH/Cu), NO was in situ produced via the Cu-catalyzed decomposition of endogenous RSNOs available in the blood, thus resolving the intrinsic shortcomings of NO therapies, such as the short storage and release time, as well as the burst and uncontrollable release modes. We demonstrated that the NO-releasing gelatin hydrogels enhanced the proliferation and migration of endothelial cells, while promoting the M2 (anti-inflammatory) polarization of the macrophage. Furthermore, the effects of NO release on angiogenesis were evaluated using an in vitro tube formation assay and in ovo chicken chorioallantoic membrane (CAM) assay, which revealed that GH/Cu hydrogels could significantly facilitate neovascularization, consistent with the in vivo results. Therefore, we suggested that these hydrogel systems would significantly enhance the wound healing process through the synergistic effects of the hydrogels and NO, and hence could be used as advanced wound dressing materials.

P-Glycoprotein Exacerbates Brain Injury Following Experimental Cerebral Ischemia by Promoting Proinflammatory Microglia Activation.

Microglia are activated following cerebral ischemic insult. P-glycoprotein (P-gp) is an efflux transporter on microvascular endothelial cells and upregulated after cerebral ischemia. This study evaluated the effects and possible mechanisms of P-gp on microglial polarization/activation in mice after ischemic stroke. P-gp-specific siRNA and adeno-associated virus (p-AAV) were used to silence and overexpress P-gp, respectively. Middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R) were performed in mice and cerebral microvascular endothelial cells (bEnd.3) in vitro, respectively. OGD/R-injured bEnd.3 cells were cocultured with mouse microglial cells (BV2) in Transwell. Influences on acute ischemic stroke outcome, the expression of inflammatory cytokines, and chemokines and chemokines receptors, microglial polarization, glucocorticoid receptor (GR) nuclear translocation, and GR-mediated mRNA decay (GMD) activation were evaluated via reverse transcription real-time polymerase chain reaction, western blot, or immunofluorescence. Silencing P-gp markedly alleviated experimental ischemia injury as indicated by reduced cerebral infarct size, improved neurological deficits, and reduced the expression of interleukin-6 (IL-6) and IL-12 expression. Silencing P-gp also mitigated proinflammatory microglial polarization and the expression of C-C motif chemokine ligand 2 (CCL2) and its receptor CCR2 expression, whereas promoted anti-inflammatory microglia polarization. Additionally, P-gp silencing promoted GR nuclear translocation and the expression of GMD relative proteins in endothelial cells. Conversely, overexpressing P-gp via p-AAV transfection offset all these effects. Furthermore, silencing endothelial GR counteracted all effects mediated by silencing or overexpressing P-gp. Elevated P-gp expression aggravated inflammatory response and brain damage after ischemic stroke by augmenting proinflammatory microglial polarization in association with increased endothelial CCL2 release due to GMD inhibition by P-gp.

MicroRNA miR-27a as a possible regulator of anti-inflammatory macrophage phenotype in preeclamptic placenta

IntroductionThe role of the TGFβ signaling pathway, an important cascade responsible for the anti-inflammatory polarization of macrophages, in the development of both early- and late-onset preeclampsia (eoPE and loPE), remains poorly understood. In this study, we examined the components of the TGFβ signaling cascade and macrophage markers within placental tissue in normal pregnancy and in PE. MethodsPatients with eoPE, loPE, and normal pregnancy were enrolled in the study (n = 10 in each group). Following techniques were used for the investigation: immunohistochemistry analysis, western blotting, qRT-PCR, isolation of monocytes by magnetic sorting, transfection, microRNA sequencing, and bioinformatic analysis. ResultsWe observed a significant decrease in the anti-inflammatory macrophage marker CD206 in the loPE group, alongside with a significant down-regulation of CD206 protein production in both eoPE and loPE groups. The level of CD68-positive cells and relative levels of CD163 and MARCO production were comparable across the groups. However, we identified a significant decrease in the TGFβ receptor 2 production and its gene expression in the PE group. Further analysis revealed a link between TGFBR2 and MRC1 (CD206) genes through a single miRNA, hsa-miR-27a-3p. Transfecting CD14-derived macrophages with the hsa-miR-27a-3p mimic significantly changed TGFBR2 production, indicating the potential role of this miRNA in regulating the TGFβ signaling pathway. We also revealed the up-regulation of hsa-miR-27a-5p and hsa-miR-27a-3p in the trophoblast BeWo b30 cell line under the severe hypoxia condition and the fact that TGFBR2 3′ UTR could serve as a potential target for these miRNAs. DiscussionOur findings uncover a novel potential therapeutic target for managing patients with PE, significantly contributing to a deeper comprehension of the underlying mechanisms involved in the development of this pathology.

An exploratory human study investigating the influence of type 2 diabetes on macrophage phenotype after myocardial infarction

BackgroundMyocardial infarction (MI) is the primary cause of death in subjects with type 2 diabetes (T2D) and their in-hospital mortality after MI is still elevated compared with those without T2D. Therefore, it is of crucial importance to identify possible mechanisms of worse clinical outcomes and mortality in T2D subjects. Monocyte/macrophage-mediated immune response plays an important role in heart remodelling to limit functional deterioration after MI. Indeed, first pro-inflammatory macrophages digest damaged tissue, then anti-inflammatory macrophages become prevalent and promote tissue repair. Here, we hypothesize that the worse clinical outcomes in patients with T2D could be the consequence of a defective or a delayed polarization of macrophages toward an anti-inflammatory phenotype. Methods and resultsIn an exploratory human study, circulating monocytes from male patients with or without T2D at different time-points after MI were in vitro differentiated toward pro- or anti-inflammatory macrophages. The results of this pilot study suggest that the phenotype of circulating monocytes, as well as the pro- and anti-inflammatory macrophage polarization, or the kinetics of the pro- and anti-inflammatory polarization, is not influenced by T2D. ConclusionFurther studies will be necessary to understand the real contribution of macrophages after MI in humans.

Lianhua Qingwen protects LPS-induced acute lung injury by promoting M2 macrophage infiltration

Ethnopharmacological relevanceTraditional Chinese medicine Lianhua Qingwen (LHQW) was used to treat regular seasonal influenza. In recent years, LHQW exerts significant therapeutic effects in treating influenza and Coronavirus Disease 2019 (COVID-19). However, the potential mechanisms are not yet understood and need further study. Aim of studyThis study aims to look into the influence of LHQW on lung inflammation and macrophage phenotype, and to clarify the connection between macrophage plasticity and LHQW. MethodsThe cell viability, marker expression, response to LPS stimulation, and phagocytosis of Raw264.7 were detected after LHQW treatment. In an LPS-induced acute lung injury (ALI) mouse model, the alleviating effect of LHQW on lung injury was investigated. The total macrophages and M2 macrophages in mice lungs and the peripheral blood monocytes after LHQW treatment were detected. The cell viability and polarization of peripheral blood macrophages treated with LHQW were detected. ResultsHere, we demonstrate that LHQW protects LPS-induced ALI by promoting M2 macrophage infiltration. LHQW treatment inhibited the inflammatory response and pro-inflammatory phenotype of Raw264.7 macrophages. High concentrations of LHQW promoted the phagocytic capacity of Raw264.7 macrophages. In an ALI mouse model, LHQW alleviated lung injury and no significant hepatotoxicity was observed. By Immunohistochemistry (IHC) analysis, LHQW increased the infiltration of macrophages, mainly M2 macrophages. Consistent with Raw264.7, LHQW also decreased the expression of M1 markers in peripheral blood macrophages. In addition, LHQW blood plasma promoted the M2-type polarization of peripheral blood macrophages. ConclusionsTaken together, our data demonstrate that LHQW reduces the inflammatory response and ameliorates acute lung injury by promoting anti-inflammatory polarization of macrophages.

Current Knowledge about the Peritumoral Microenvironment in Glioblastoma.

Glioblastoma is a deadly disease, with a mean overall survival of less than 2 years from diagnosis. Recurrence after gross total surgical resection and adjuvant chemo-radiotherapy almost invariably occurs within the so-called peritumoral brain zone (PBZ). The aim of this narrative review is to summarize the most relevant findings about the biological characteristics of the PBZ currently available in the medical literature. The PBZ presents several peculiar biological characteristics. The cellular landscape of this area is different from that of healthy brain tissue and is characterized by a mixture of cell types, including tumor cells (seen in about 30% of cases), angiogenesis-related endothelial cells, reactive astrocytes, glioma-associated microglia/macrophages (GAMs) with anti-inflammatory polarization, tumor-infiltrating lymphocytes (TILs) with an "exhausted" phenotype, and glioma-associated stromal cells (GASCs). From a genomic and transcriptomic point of view, compared with the tumor core and healthy brain tissue, the PBZ presents a "half-way" pattern with upregulation of genes related to angiogenesis, the extracellular matrix, and cellular senescence and with stemness features and downregulation in tumor suppressor genes. This review illustrates that the PBZ is a transition zone with a pre-malignant microenvironment that constitutes the base for GBM progression/recurrence. Understanding of the PBZ could be relevant to developing more effective treatments to prevent GBM development and recurrence.