Number Of Macrophages Research Articles

High doses of radiation cause cochlear immunological stress and sensorineural hearing loss

Radiotherapy is a crucial treatment for head and neck malignancies, but it can sometimes cause sensorineural hearing loss (SNHL). Changes in the immune microenvironment and sensory neuroepithelium of the inner ear after radiation exposure remain poorly understood. This study investigated cochlear morphology and macrophages in the inner ear after high-dose irradiation. The heads of heterozygous 8-week-old Cx3cr1GFP/+ male mice were irradiated with 30Gy of X-rays and biological samples were collected on days 1, 7, and 10 after irradiation. Auditory brainstem responses were used to assess auditory function in the mice. Changes in basilar membrane hair cells, spiral ganglion neurons (SGN), and inner ear macrophages were observed using hematoxylin-eosin (HE) staining and immunofluorescence staining. The expression of inflammatory mediators in the inner ear was detected by quantitative real-time reverse transcription-polymerase chain reaction (RT-qPCR) in cochlear tissue. The results showed no significant hair cell loss after a single high dose of radiation. However, the mice developed pantonal hearing loss on day 10 when HE staining revealed SGN atrophy and immunofluorescence showed decreased neurofilament expression. The number of macrophages in the inner ear reduced over time. RT-qPCR showed that cochlear inflammatory factors and chemokines were briefly upregulated on day 1st after irradiation and then decreased over time. In conclusion, high-dose irradiation causes acute SNHL that is not associated with hair cell loss and may be related to SGN changes. Radiation-induced SNHL is associated with a reduction in cochlear macrophages and changes in the immune microenvironment, but the relationship between the two remains to be investigated.

Polydatin and chitosan-silver co-loaded nanocomplexes for synergistic treatment of rheumatoid arthritis via repolarizing macrophages and inducing apoptosis of fibroblast-like synoviocytes

Rheumatoid arthritis (RA) is a chronic and refractory autoimmune disease that primarily affects the synovium of diarthrodial joints. Inflammatory macrophages and fibroblast-like synoviocytes (FLS) in the synovial microenvironment produce pathogenic mediators such as cytokines and proteases that perpetuate immune-mediated inflammation and contribute to the destruction of cartilage and bone. Polydatin (PD), a natural active compound, has demonstrated potential anti-inflammatory and anti-arthritic effects. However, drug development and delivery of PD is still a great challenge owing to its low solubility, short half-life, and high dose requirement. In order to overcome these drawbacks, we developed a novel nanodrug system named HA-M@PB@Ag@PD NPs. This system is composed of hybrid membrane (M), hyaluronic acid (HA), Prussian blue nanoparticles (PB NPs), PD, and chitosan-silver (Chi-Ag). In vitro experiments demonstrated that HA-M@PB@Ag@PD NPs effectively cleared ROS, promoted the repolarization of inflammatory macrophages, and induced apoptosis of RA-FLS. Using a rat model of RA, HA-M@PB@Ag@PD NPs markedly suppressed joint inflammation, inhibited synovial hyperplasia, and protected joints against destruction of cartilage and bone. Moreover, HA-M@PB@Ag@PD NPs significantly improved the synovial microenvironment of arthritic rats by reducing the number of RA-FLS and inflammatory macrophages, and facilitating the repolarization of inflammatory macrophages.

In vivo toxicity of upconversion nanoparticles (NaYF4:Yb, Er) in zebrafish during early life stages: Developmental toxicity, gut-microbiome disruption, and proinflammatory effects

Lanthanide-doped upconversion nanoparticles (Ln-UCNPs) have been considered promising materials for various fields, such as biomedical and industrial applications. However, data and reports regarding its toxicity and environmental risks are scarce. Under these circumstances, data must be obtained to fully understand potential toxicity and adverse outcome pathways. In the present study, the toxicity of uncoated Ln-UCNP cores (NaYF4:Yb, Er) was systematically assessed in zebrafish embryos during early developmental stages. Ln-UCNPs were found to have multiple toxic effects, such as effects on survival rates, delayed hatching times, shorter body lengths, altered heart rates and blood circulation (significantly reduced), and neurobehavioral impairments in response to photoperiod stimulation. Bioimaging showed that Ln-UCNPs were distributed on the chorion, eyes, and skin at 72 hpf. However, it accumulates in the pharynx, esophagus, and intestine after oral administration. Ln-UCNPs disrupt the diversity and abundance of host-associated microorganisms (gut microbiota) leading to an increase in the prevalence of harmful bacteria in zebrafish. Transcriptomic and Ingenuity Pathway Analysis (IPA) predicted Interleukin-8 (IL-8) signaling, neuroinflammation, cardiac hypertrophy signaling pathways, immune and inflammation-related response interferon-gamma (ifnγ), and miR-155 as key mediators in regulatory effects. Based on this, a causal network was built showing the strong links between the induced gene expression of differentially expressed genes (DEGs), such as nitric oxide synthase 2 (nos2) and tumor necrosis factor (tnf) upon Ln-UCNPs treatment, and with the downstream adverse outcomes, in particular, the promotion of apoptosis, liver damage, and inflammatory response. Finally, RT-qPCR analysis confirmed the up-regulated expression of nos2 and tnf in the exposed larvae, consistent with the observation of an increased number of fluorescence-labelled neutrophils and macrophages in lyz: DsRed transgenic zebrafish until 120 hpf exposure, which together demonstrated the proinflammatory effects of Ln-UCNPs on organisms. In conclusion, we illustrated the developmental toxicity, disruption of gut-microbiome, and proinflammatory effects of Ln-UCNP cores on zebrafish, and the causal network from IPA analysis may help further elucidate the adverse outcome pathway of Ln-UCNPs.

Obesity-derived macrophages upregulate TNF-α to induce apoptosis in glial cell via the NF-κB/PHLPP1 axis

Macrophages in obese adipose tissue have been shown to damage nerve fibers, however, the mechanism underlying how macrophages cause glial cell damage remains unknown. This study aimed to characterize the mechanism by which macrophages induce apoptosis in glial cell during obesity formation in mice by single-nucleus RNA sequencing (snRNA-seq). Cells obtained from paraepididymal adipose tissue in obese mice underwent snRNA-seq. Eighteen different clusters were identified, and 12 cell types were annotated, including glial cells, macrophages, and fibroblasts. There was a negative correlation between the number of glial cells and macrophages in mouse adipose tissue during the formation of obesity. The pro-apoptotic factor PHLPP1 was identified in GO Terms. The interaction between adipose tissue glial cells and macrophages was revealed via in-depth analysis, and the cell–cell communication mechanism between the TNF-α and NF-KB/PHLPP1 axes was perfected. Apoptosis of glial cell by upregulation of TNF-α via obesity-derived macrophages and activation of the NF-κB/PHLPP1 axis. We further revealed how macrophages induce apoptosis in glial cells during obesity formation, as well as different changes in the two cell populations. This study provides valuable resources and foundations for understanding the mechanistic effects of macrophages and glial cells during obesity formation, as well as diseases and potential interventions.

PTEN loss shapes macrophage dynamics in high grade serous ovarian carcinoma.

High-grade serous ovarian carcinoma (HGSC) remains a disease of poor prognosis that is unresponsive to current immune checkpoint inhibitors. Although PI3K pathway alterations, such as PTEN loss, are common in HGSC, attempts to target this pathway have been unsuccessful. We hypothesized that aberrant PI3K pathway activation may alter the HGSC immune microenvironment and present a targeting opportunity. Single-cell RNA sequencing identified populations of resident macrophages specific to Pten-null omental tumors in murine models, which were confirmed by flow cytometry. These macrophages derived from peritoneal fluid macrophages and had a unique gene expression program, marked by high expression of the enzyme heme oxygenase-1 (HMOX1). Targeting resident peritoneal macrophages prevented the appearance of HMOX1hi macrophages and reduced tumor growth. Furthermore, direct inhibition of HMOX1 extended survival in vivo. RNA sequencing identified IL33 in Pten-null tumor cells as a likely candidate driver leading to the appearance of HMOX1hi macrophages. Human HGSC tumors also contained HMOX1hi macrophages with a corresponding gene expression program. Moreover, the presence of these macrophages correlated with activated tumoral PI3K/mTOR signaling and poor overall survival in HGSC patients. In contrast, tumors with low numbers of HMOX1hi macrophages were marked by increased adaptive immune response gene expression. These data suggest targeting HMOX1hi macrophages as a potential therapeutic strategy for treating poor prognosis HGSC.

CCN4 (WISP-1) reduces apoptosis and atherosclerotic plaque burden in an ApoE mouse model

Background and aimsCCN4/WISP-1 regulates various cell behaviours that contribute to atherosclerosis progression, including cell adhesion, migration, proliferation and survival. We therefore hypothesised that CCN4 regulates the development and progression of atherosclerotic plaques. MethodsWe used a high fat fed ApoE−/− mouse model to study atherosclerotic plaque progression in the brachiocephalic artery and aortic root. In protocol 1, male ApoE−/− mice with established plaques were given a CCN4 helper-dependent adenovirus to see the effect of treatment with CCN4, while in protocol 2 male CCN4−/−ApoE−/− were compared to CCN4+/+ApoE−/− mice to assess the effect of CCN4 deletion on plaque progression. ResultsCCN4 overexpression resulted in reduced occlusion of the brachiocephalic artery with less apoptosis, fewer macrophages, and attenuated lipid core size. The amount of plaque found on the aortic root was also reduced. CCN4 deficiency resulted in increased apoptosis and occlusion of the brachiocephalic artery as well as increased plaque in the aortic root. Additionally, in vitro cells from CCN4−/−ApoE−/− mice had higher apoptotic levels. CCN4 deficiency did not significantly affect blood cholesterol levels or circulating myeloid cell populations. ConclusionsWe conclude that in an atherosclerosis model the most important action of CCN4 is the effect on cell apoptosis. CCN4 provides pro-survival signals and leads to reduced cell death, lower macrophage number, smaller lipid core size and reduced atherosclerotic plaque burden. As such, the pro-survival effect of CCN4 is worthy of further investigation, in a bid to find a therapeutic for atherosclerosis.

The Complement System Is Essential for Arteriogenesis by Enhancing Sterile Inflammation as a Relevant Step in Collateral Artery Growth.

Arteriogenesis is an inflammatory driven mechanism, describing the growth of a natural bypass from pre-existing collateral arteries to compensate for an occluded artery. The complement system component C3 is a potent natural inflammatory activator. Here, we investigated its impact on the process of collateral artery growth using C3-deficient (C3 -/-) and wildtype control mice in a murine hindlimb model of arteriogenesis. Induction of arteriogenesis by unilateral femoral artery ligation resulted in decreased perfusion recovery in C3 -/- mice on day 7 as shown by Laser Doppler imaging. Immunofluorescence staining revealed a reduced vascular cell proliferation in C3 -/- mice. Gene expression analysis displayed a significant reduction in monocyte chemoattractant protein-1 (MCP-1) expression in C3 -/- mice. Interestingly, 3 days after induction of arteriogenesis, the number of macrophages (CD68+) recruited to growing collaterals was not affected by C3 deficiency. However, a significant reduction in inflammatory M1-like polarized macrophages (CD68+/MRC1-) was noted. Forced mast cell activation by Compound 48/80 as well as exogenous MCP-1 application rescued the number of M1-like polarized macrophages along with perfusion recovery in C3 -/- mice. In summary, this study demonstrates that complement C3 influences arteriogenesis by mediating MCP-1 expression, which is essential for the induction and enhancement of sterile inflammation.

Hypoxia-induced complement component 3 promotes aggressive tumor growth in the glioblastoma microenvironment.

Glioblastoma (GBM) is the most aggressive form of glioma with a high rate of relapse despite intensive treatment. Tumor recurrence is tightly linked to radio-resistance, which in turn is associated with hypoxia. Here, we discovered a strong link between hypoxia and local complement signaling using publicly available bulk, single-cell, and spatially resolved transcriptomic data from patients with GBM. Complement component 3 (C3) and the receptor C3AR1 were both associated with aggressive disease and shorter survival in human glioma. In a genetically engineered mouse model of GBM, we found C3 specifically in hypoxic tumor areas. In vitro, we found an oxygen level-dependent increase in C3 and C3AR1 expression in response to hypoxia in several GBM and stromal cell types. C3a induced M2 polarization of cultured microglia and macrophages in a C3aR-dependent fashion. Targeting C3aR using the antagonist SB290157 prolonged survival of glioma-bearing mice both alone and in combination with radiotherapy while reducing the number of M2-polarized macrophages. Our findings establish a strong link between hypoxia and complement pathways in GBM and support a role of hypoxia-induced C3a/C3aR signaling as a contributor to glioma aggressiveness by regulating macrophage polarization.

Mutant IDH Modulates Suppressive Myeloid Populations in Malignant Glioma.

Mutations in the isocitrate dehydrogenase (IDH) genes IDH1 and IDH2 have critical diagnostic and prognostic significance in diffuse gliomas. Neomorphic mutant IDH activity has been previously implicated in T-cell suppression; however, the effects of IDH mutations on intratumoral myeloid populations remain underexplored. In this study, we investigate the influence of IDH status on the myeloid compartment using human glioma specimens and preclinical models. We performed RNA sequencing and quantitative immunofluorescence on newly diagnosed, treatment-naive IDH-mutant grade 4 astrocytoma and IDH-wild-type (IDH-WT) glioblastoma (GBM) specimens. We also generated a syngeneic murine model, comparing transcriptomic and cell-level changes in paired isogenic glioma lines that differ only in IDH mutational status. Among patient samples, IDH-mutant tumors displayed an underrepresentation of suppressive myeloid transcriptional signatures, which was confirmed at the cellular level with decreased numbers of intratumoral M2-like macrophages and myeloid-derived suppressor cells. Introduction of the mutant IDH enzyme into murine glioma was sufficient to recapitulate the transcriptomic and cellular shifts observed in patient samples. We provide transcriptomic and cellular evidence that mutant IDH is associated with a quantitative reduction of suppressive myeloid cells in gliomas and that introduction of the mutant enzyme is sufficient to result in corresponding cellular changes using an in vivo preclinical model. These data advance our understanding of high-grade gliomas by identifying key myeloid cell populations that are reprogrammed by mutant IDH and may be targetable through therapeutic approaches.

Multimodal Imaging-Assisted Intravascular Theranostic Photoactivation on Atherosclerotic Plaque.

Atherosclerosis is a chronic inflammatory disease causing a fatal plaque rupture, and its key aspect is a failure to resolve inflammation. We hypothesize that macrophage-targeted near-infrared fluorescence emitting photoactivation could simultaneously assess macrophage/lipid-rich plaques in vivo and facilitate inflammation resolution. We fabricated a Dectin-1-targeted photoactivatable theranostic agent through the chemical conjugation of the near-infrared fluorescence-emitting photosensitizer chlorin e6 and the Dectin-1 ligand laminarin (laminarin-chlorin e6 [LAM-Ce6]). Intravascular photoactivation by a customized fiber-based diffuser after administration of LAM-Ce6 effectively reduced inflammation in the targeted plaques of atherosclerotic rabbits in vivo as serially assessed by dual-modal optical coherence tomography-near-infrared fluorescence structural-molecular catheter imaging after 4 weeks. The number of apoptotic macrophages peaked at 1 day after laser irradiation and then resolved until 4 weeks. Autophagy was strongly augmented 1 hour after the light therapy, with the formation of autophagolysosomes. LAM-Ce6 photoactivation increased the terminal deoxynucleotidyl transferase dUTP (deoxyuridine triphosphate) nick end labeling/RAM11 (rabbit monocyte/macrophage antibody)- and MerTK (c-Mer tyrosine kinase)-positive cells in the plaques, suggesting enhanced efferocytosis. In line with inflammation resolution, photoactivation reduced the plaque burden through fibrotic replacement via the TGF (transforming growth factor)-β/CTGF (connective tissue growth factor) pathway. Optical coherence tomography-near-infrared fluorescence imaging-guided macrophage Dectin-1-targetable photoactivation could induce the transition of macrophage/lipid-rich plaques into collagen-rich lesions through autophagy-mediated inflammation resolution and TGF-β-dependent fibrotic replacement. This novel strategy offers a new opportunity for the catheter-based theranostic strategy.

Comprehensive genomic and spatial immune infiltration analysis of survival outliers in extensive-stage small cell lung cancer receiving first-line chemoimmunotherapy

BackgroundA minority of patients with extensive-stage small cell lung cancer (ES-SCLC) exhibit prolonged survival following first-line chemoimmunotherapy, which warrants the use of reliable biomarkers. Here, we investigated the disparities in genomics and immune cell spatial distribution between long- and short-term survival of patients with ES-SCLC. MethodsWe retrospectively recruited 11 long-term (>2 years) and 13 short-term (<9 months) ES-SCLC survivors receiving first-line chemoimmunotherapy. The samples were processed using targeted next-generation sequencing (tNGS), programmed death ligand-1 staining, multiplex immunohistochemical staining for immune cells (mIHC), tumor mutation burden (TMB), and chromosomal instability score measurements. The expression of putative genes in SCLC at the bulk and single-cell RNA-sequencing levels, as well as the role of putative genes in pan-cancer immunotherapy cohorts, were analyzed. ResultsAt the genomic level, a greater proportion of the smoking signature and higher TMB (>3.1) were associated with favorable survival. At the single-gene and pathway levels, tNGS revealed that MCL1 and STMN1 amplification and alterations in the apoptosis pathway were more common in short-term survivors, whereas alterations in the DLL3, KMT2B, HGF, EPHA3, ADGRB3, lysine deprivation, and HGF-cMET pathways were observed more frequently in long-term survivors. mIHC analysis of immune cells with different spatial distributions revealed that long-term survivors presented increased numbers of M1-like macrophages in all locations and decreased numbers of CD8+ T cells in the tumor stroma. Bulk transcriptomic analysis demonstrated that high levels of STMN1 and DLL3 represented an immune-suppressive tumor immune microenvironment (TIME), whereas HGF indicated an immune-responsive TIME. The expression levels of our putative genes were comparative in both TP53/RB1 mutant-type and TP53/RB1 wild-type. At the single-cell level, STMN1, MCL1, and DLL3 were highly expressed among all molecular subtypes (SCLC-A, SCLC-N, and SCLC-P), with STMN1 being enriched in cell division and G2M checkpoint pathways. ConclusionsFor ES-SCLC patients receiving first-line chemoimmunotherapy, alterations in DLL3, KMT2B, HGF, EPHA3, and ADGRB3 and a greater proportion of M1-like macrophages infiltration in all locations were predictors of favorable survival, while MCL1 and STMN1 amplification, as well as a greater proportion of CD8+ T cells infiltrating the tumor stroma, predicted worse survival.

The Impact of TP53-Induced Glycolysis and Apoptosis Regulator on Prognosis in Hepatocellular Carcinoma: Association with Tumor Microenvironment and Ferroptosis

&lt;b&gt;&lt;i&gt;Introduction:&lt;/i&gt;&lt;/b&gt; &lt;i&gt;TP53&lt;/i&gt;-induced glycolysis and apoptosis regulator (TIGAR) is a p53 target protein that has critical roles in glycolysis and redox balance. The reports about the effect of TIGAR on prognosis and its biological role in hepatocellular carcinoma (HCC) are limited. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; A total of 386 patients with HCC who had undergone hepatic resection were enrolled. Immunohistochemical staining for TIGAR was performed. Additionally, the regulation of malignant activity and ferroptosis by TIGAR was investigated in vitro. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; Patients were divided into TIGAR-positive (&lt;i&gt;n&lt;/i&gt; = 80, 20.7%) and -negative (&lt;i&gt;n&lt;/i&gt; = 306, 79.3%) groups. TIGAR positivity was significantly correlated with lower albumin, higher α-fetoprotein/ &lt;i&gt;des&lt;/i&gt;-gamma-carboxyprothrombin, larger tumor size/number of tumors, and greater proportions of BCLC staging C/single nodular type/poor differentiation/microscopic vascular invasion/microscopic intrahepatic metastasis. In multivariate analysis, TIGAR positivity was an independent prognostic factor (&lt;i&gt;p&lt;/i&gt; &amp;lt; 0.0001). In addition, TIGAR positivity was significantly associated with a smaller number of cluster of differentiation (CD) 8-positive T cells (&lt;i&gt;p&lt;/i&gt; = 0.0450), larger number of CD68-positive macrophages (&lt;i&gt;p&lt;/i&gt; = 0.0058), larger number of programmed death-ligand 1-positive cases (&lt;i&gt;p&lt;/i&gt; = 0.0002), and larger number of vessels that encapsulate tumor cluster-positive cases (&lt;i&gt;p&lt;/i&gt; = 0.0004). In vitro, &lt;i&gt;TIGAR&lt;/i&gt; knockdown decreased cell motility and induced ferroptosis. &lt;i&gt;TIGAR&lt;/i&gt; knockdown inhibited the phosphorylation of adenosine monophosphate-activated protein kinase and acetyl-CoA carboxylase. Ferroptosis induced by &lt;i&gt;TIGAR&lt;/i&gt; knockdown was inhibited by liproxstatin and baicalein treatment. The combination of &lt;i&gt;TIGAR&lt;/i&gt; knockdown and lenvatinib further induced ferroptosis. &lt;b&gt;&lt;i&gt;Conclusion:&lt;/i&gt;&lt;/b&gt; High expression of TIGAR impacted the clinical outcome of HCC patients and TIGAR was associated not only with tumor microenvironment but also with resistance to ferroptosis.

Immunoregulatory Cells and Cytokines Discriminate Disease Activity Score 28-Remission Statuses and Ultrasound Grades in Rheumatoid Arthritis Patients with Non-High Disease Activity.

It is not clear whether immunoregulatory cytokines and cells are associated with Disease Activity Score 28 (DAS28) scores and ultrasound grades/scores. Here, we investigated the relationships between immunoregulatory cytokines or cells and different DAS28 scores or ultrasound grades/scores in patients with rheumatoid arthritis (RA). This study enrolled 50 RA patients (with 147 visits) who had remission/low/moderate DAS28-ESR scores (92% in remission and low disease activity) at baseline. Blood was collected and an ultrasound was performed three times in a year. Percentages of regulatory B cells and T regulatory type 1 cells and M2 macrophage numbers in the blood were examined. Plasma levels of 10 immunoregulatory cytokines IL-4, IL-5, IL-9, IL-10, IL-13, IL-27, IL-35, TGF-β1, sTNF-R1, and sTNF-R2 and monocyte chemotactic protein-1 (MCP-1) were assessed using ELISA assay. The correlations of cytokines and cells with different DAS28 scores and ultrasound grades were investigated, and cytokines and cells were compared between different categories of DAS28 scores and ultrasound grades. Plasma TGF-β1 levels were higher in the DAS28-ESR < 2.6 (remission) subgroup than in the DAS28-ESR ≥ 2.6 (nonremission) subgroup (p = 0.037). However, plasma TGF-β1 levels were higher in the high ultrasound grade subgroup than those in the low ultrasound grade subgroup (p = 0.007). The number of M2 macrophages was lower in the DAS28-MCP-1 < 2.2 subgroup than in the DAS28-MCP-1 ≥ 2.2 subgroup (p = 0.036). The levels of TGF-β1, sTNF-R2, IL-10, and IL-27 were higher in patients with high ultrasound grades than in those with low ultrasound grades. IL-27 was also higher in the nonremission DAS28-ESR subgroup than the remission one (p = 0.025). Moreover, sTNF-R1 levels in the 2011 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission subgroup were significantly lower than in the 2011 ACR/EULAR nonremission subgroup (p = 0.007). This trend was reflected in that lower sTNF-R1 levels correlated with low DAS28-MCP-1 scores (rho = 0.222, p = 0.007). We conclude that high plasma TGF-β1 levels indicate the DAS28-ESR remission (<2.6) subgroup and the high ultrasound grade subgroup. IL-27 probably connects the nonremission DAS28-ESR to high ultrasound grades. Low sTNF-R1 levels probably link low DAS28-MCP-1 scores with the 2011 ACR/EULAR remission subgroup. It suggests that incongruent immuno-inflammatory abnormalities exist between DAS28 scores and ultrasound grades, and are also dissimilar among various DAS28-formula categories. Therefore, this study may provide a basis for further research into individual cytokines and immunoregulatory cells behind each DAS28 formula and ultrasound grades/scores.

Pharmacological mechanisms of Ma Xing Shi Gan Decoction in treating influenza virus-induced pneumonia: intestinal microbiota and pulmonary glycolysis.

Influenza virus is one of the most common pathogens that cause viral pneumonia. During pneumonia, host immune inflammation regulation involves microbiota in the intestine and glycolysis in the lung tissues. In the clinical guidelines for pneumonia treatment in China, Ma Xing Shi Gan Decoction (MXSG) is a commonly prescribed traditional Chinese medicine formulation with significant efficacy, however, it remains unclear whether its specific mechanism of action is related to the regulation of intestinal microbiota structure and lung tissue glycolysis. This study aimed to investigate the mechanism of action of MXSG in an animal model of influenza virus-induced pneumonia. Specifically, we aimed to elucidate how MXSG modulates intestinal microbiota structure and lung tissue glycolysis to exert its therapeutic effects on pneumonia. We established a mouse model of influenza virus-induced pneumoni, and treated with MXSG. We observed changes in inflammatory cytokine levels and conducted 16S rRNA gene sequencing to assess the intestinal microbiota structure and function. Additionally, targeted metabolomics was performed to analyze lung tissue glycolytic metabolites, and Western blot and enzyme-linked immunosorbent assays were performed to assess glycolysis-related enzymes, lipopolysaccharides (LPSs), HIF-1a, and macrophage surface markers. Correlation analysis was conducted between the LPS and omics results to elucidate the relationship between intestinal microbiota and lung tissue glycolysis in pneumonia animals under the intervention of Ma Xing Shi Gan Decoction. MXSG reduced the abundance of Gram-negative bacteria in the intestines, such as Proteobacteria and Helicobacter, leading to reduced LPS content in the serum and lungs. This intervention also suppressed HIF-1a activity and lung tissue glycolysis metabolism, decreased the number of M1-type macrophages, and increased the number of M2-type macrophages, effectively alleviating lung damage caused by influenza virus-induced pneumonia. MXSG can alleviate glycolysis in lung tissue, suppress M1-type macrophage activation, promote M2-type macrophage activation, and mitigate inflammation in lung tissue. This therapeutic effect appears to be mediated by modulating gut microbiota and reducing endogenous LPS production in the intestines. This study demonstrates the therapeutic effects of MXSG on pneumonia and explores its potential mechanism, thus providing data support for the use of traditional Chinese medicine in the treatment of respiratory infectious diseases.

Mechanically induced M2 macrophages are involved in bone remodeling of the midpalatal suture during palatal expansion

BackgroundPalatal expansion is a common way of treating maxillary transverse deficiency. Under mechanical force, the midpalatal suture is expanded, causing local immune responses. This study aimed to determine whether macrophages participate in bone remodeling of the midpalatal suture during palatal expansion and the effects on bone remodeling.MethodsPalatal expansion model and macrophage depletion model were established. Micro-CT, histological staining, and immunohistochemical staining were used to investigate the changes in the number and phenotype of macrophages during palatal expansion as well as the effects on bone remodeling of the midpalatal suture. Additionally, the effect of mechanically induced M2 macrophages on palatal osteoblasts was also elucidated in vitro.ResultsThe number of macrophages increased significantly and polarized toward M2 phenotype with the increase of the expansion time, which was consistent with the trend of bone remodeling. After macrophage depletion, the function of osteoblasts and bone formation at the midpalatal suture were impaired during palatal expansion. In vitro, conditioned medium derived from M2 macrophages facilitated osteogenic differentiation of osteoblasts and decreased the RANKL/OPG ratio.ConclusionsMacrophages through polarizing toward M2 phenotype participated in midpalatal suture bone remodeling during palatal expansion, which may provide a new idea for promoting bone remodeling from the perspective of regulating macrophage polarization.

Toll-Like Receptor 7-Expressed Macrophages Are Involved in the Pathogenesis of Esophageal Achalasia and Esophagogastric Junction Outflow Obstruction.

Esophageal achalasia is a typical esophageal motility disorder (EMD). Although viral infections have been hypothesized to play a role in the pathogenesis of esophageal achalasia, its etiology remains unclear. This study used esophageal muscle layer specimens collected during per-oral endoscopic myotomy (POEM) procedures to investigate the association between esophageal achalasia and esophagogastric junction outflow obstruction (EGJOO) and pattern recognition receptors. Patients with esophageal achalasia and EGJOO who underwent POEM were allocated to the EMD group. Biopsies of the inner circular muscle were conducted during the POEM procedure. The control group comprised individuals diagnosed with esophageal squamous cell carcinoma who underwent surgical resection. Expression of pattern recognition receptors, including Toll-like receptor (TLR) 7, was examined by polymerase chain reaction. Immunohistochemical staining was performed to determine TLR7 expression sites in the esophageal muscle layer, and the relationship between TLR7 mRNA expression and clinical score was investigated. Our analysis revealed a notable upregulation of TLR7 mRNA levels within the muscle layer of esophageal achalasia and EGJOO, in contrast to those of control specimens. In contrast, the correlation between TLR7 and clinical score was not significant. Immunohistochemical staining revealed increased numbers of TLR7-expressing macrophages between the muscle layers. TLR7-expressing macrophages are involved in the innate immune response underlying esophageal achalasia and EGJOO. This result will lead to the elucidation of new pathogenetic mechanisms and the development of novel therapeutic targets.

The effect of curcumin 1% methanolic extract on the expression of Matrix Metalloproteinase-1, Matrix Metalloproteinase-8, Matrix Metalloproteinase-13, neutrophil, macrophage, lymphocyte counts in Porphyromonas gingivalis induced periodontitis: a randomized controlled trial

ObjectiveHailed as one of the most fundamental and important treatment in management of periodontal disease, scalling and root planning has limitations regarding microorganism elimination. Meanwhile, turmeric has been proven to have a therapeutic effect on gingivitis and periodontitis. This study aimed to analyze the impact of curcumin 1% methanolic extract on the expression of Matrix Metalloproteinase-1, Matrix Metalloproteinase-8, Matrix Metalloproteinase -13, neutrophil, macrophage, and lymphocyte number in the gingiva of Wistar rats exposed to Porphyromonas gingivalis bacteria (P. gingivalis). Materials and methodsThe experimental animals used were Wistar rats, arbitrarilly split up into three experimental groups namely: normal, control (induced with periodontitis, received no treatment), and treatment (Periodontitis with 1% curcumin treatment). The samples were taken from the gingival tissue of the mandibular incisors on 1 and 7 days. Immunohistochemical and Hematoxylin Eosin staining were performed to measure the expression of Matrix Metalloproteinase-1, Matrix Metalloproteinase-8, Matrix Metalloproteinase-13, and the number of neutrophils, macrophages, and lymphocytes. Data were analyzed for mean standard deviation. The Oneway ANOVA was then performed to see whether there is a significant difference between experimental groups, the test then commenced with Tukey’s Honestly Significant Difference test with a significance level (α=0.05). ResultsMMP-8, MMP-13, neutrophil, and lymphocyte numbers in the treatment groups were significantly lower with P<0.05 than in the control groups in the 1 and 7 days. Meanwhile, in MMP-1 and macrophage numbers the difference was deemed not significant when control and treatment groups are compared. ConclusionThe administration of 1% curcumin can significantly reduce the expression of MMP-8, MMP-13, neutrophil and lymphocyte cell numbers, but there is no reducing the number of macrophage cells and MMP-1 expression in gingiva of Wistar rats exposed to P. gingivalis bacteria.

Abstract Tu023: The VEGF-A splice variants as a mechanism of impaired Inflammatory Angiogenesis in the context of advanced aging.

Background and Objectives: Aging and age-related diseases like peripheral artery disease (PAD) is associated with impairment of angiogenesis responses to injury. Critical ischemic limb and wound injury animal models have shown impact of monocytes/macrophages as a major source of angiogenic mediators leading to new arterial growth. Aging has also been associated with impairment of blood flow recovery and reduced VEGF-A expression in animals. However, recombinant VEGF-A administration or clinical trials involving VEGF-A have not fully overcome the foot perfusion and prevent limb/leg amputation. We sought to understand molecular mechanisms of reduced VEGF-A expression which remain incomplete in the context of advanced aging. Results: Firstly, in hindlimb ischemia mouse model, our data from liposomes containing-clodronate treated mice (12-weeks C57Bl6 with macrophage depletion model ) ( Fig. 1a ) demonstrate impairment of blood flow recovery compared to Control group. On day 3 post-surgery, VEGF-A and VEGF-A isoforms expression (VEGF-A 165 a and VEGF-A 165 b, respectively) were reduced in ischemic muscle. Fluorescence staining showed a reduction of macrophages (CD68 + ) was also associated with reduced endothelial cells (CD31 + ). Using a myeloid-specific and inducible deleted VEGF fl/fl mice, we then have shown a key role of early inflammatory macrophages stage as a major source of VEGF-A required for angiogenesis in young mice (Fig. 1b). Secondly, bone marrow-derived-macrophages (BMDMs) from C57Bl6 104-weeks mice also demonstrate reduced VEGF-A expression. Aged BMDMs demonstrate reduced VEGF-A 165 a while VEGF-A 165 b was highly increased. Polarized BMDMs from 12-weeks demonstrate increased VEGFR1 in “M2" macrophages while VEGFR2 was increased in “M1” macrophages. On the other hand, BMDMs from 104-weeks demonstrate reduced VEGFR2 expression while VEGFR1 was unaffected compared to young. Lastly, 104-weeks mice also demonstrate severe impairment of blood flow recovery ( Fig. 2 ) after surgery and reduced VEGF-A and VEGF-A 165 a in ischemic muscle tissue. VEGF-A 165 b was increased and both receptors, VEGF-R1/R2 levels ( Fig. 3 ) were also reduced. Fluorescence staining on day 3 post ligation demonstrates reduced endothelial cells recruitment in muscle tissue while macrophage (CD68+) number was similar. Conclusion: Our investigations will contribute to define mechanisms whereby vascular injury is associated with VEGF-A isoforms specific switch in the context of advanced aging.

Aucubin suppresses TLR4/NF-κB signalling to shift macrophages toward M2 phenotype in glucocorticoid-associated osteonecrosis of the femoral head.

In this study, we investigated whether the ability of aucubin to mitigate the pathology of GONFH involves suppression of TLR4/NF-κB signalling and promotion of macrophage polarization to an M2 phenotype. In necrotic bone tissues from GONFH patients, we compared levels of pro-inflammatory M1 macrophages and anti-inflammatory M2 macrophages as well as levels of TLR4/NF-κB signalling. In a rat model of GONFH, we examined the effects of aucubin on these parameters. We further explored its mechanism of action in a cell culture model of M1 macrophages. Necrotic bone tissues from GONFH patients contained a significantly increased macrophage M1/M2 ratio, and higher levels of TLR4, MYD88 and NF-κB p65 than bone tissues from patients with hip osteoarthritis. Treating GONFH rats with aucubin mitigated bone necrosis and demineralization as well as destruction of trabecular bone and marrow in a dose-dependent manner, based on micro-computed tomography. These therapeutic effects were associated with a decrease in the overall number of macrophages, decrease in the proportion of M1 macrophages, increase in the proportion of M2 macrophages, and downregulation of TLR4, MYD88 and NF-κB p65. These effects invivo were confirmed by treating cultures of M1 macrophage-like cells with aucubin. Aucubin mitigates bone pathology in GONFH by suppressing TLR4/NF-κB signalling to shift macrophages from a pro- to anti-inflammatory phenotype.

The combination of apatinib and antigen-specific DC-induced T cells exert antitumor effects by potently improving the immune microenvironment of osteosarcoma

ObjectiveOsteosarcoma (OS) is the most common primary bone sarcoma with a high propensity for local invasion and metastasis. Although the antitumor effect of apatinib has been well confirmed in advanced OS, the synergistic effect of apatinib and immunotherapies has not yet been elucidated. MethodsIn this study, we established tumour-bearing mice and observed tumour size with low and high doses of apatinib treatments. The expression of 17 cytokines, including vascular endothelial growth factor (VEGF), was detected by protein microarray analysis. Moreover, we designed apatinib and antigen-specific dendritic cell (DC)-T combination treatment for tumour-bearing mice. Tumour growth was detected by statistical analysis of tumour size and microvessel density (MVD) counting, the protein expression of VEGF by western blotting, the cytokines interleukin 6 (IL-6), IL-17 and interferon-gamma (IFN-γ) by enzyme-linked immunosorbent assay (ELISA), and the numbers of myeloid-derived suppressor cells (MDSCs) and tumour-infiltration macrophages (TAMs) by flow cytometry. ResultsThe results showed that apatinib efficiently suppressed tumour growth, and high-dose apatinib achieved a stronger effect. The same was true for DC-T immunotherapy. However, their combination treatment revealed a better oncolytic effect. Meanwhile, apatinib or DC-T treatment inhibited the expression of VEGF and the proangiogenic mediators IL-6 and IL-17 but increased IFN-γ production. Combination therapy further reduced/increased these effects. In addition, the combination treatment reduced MDSC but enhanced TAM-M1 ratios in the OS microenvironment. These findings indicated that apatinib and antigen-specific DC-T combination therapy was more efficient in oncolysis by regulating pro-/anti-angiogenic inducers and improving the immune state in the OS microenvironment. ConclusionThis study proved that it was feasible to employ immunotherapy with therapeutic agents in OS treatment, which may provide a new approach in addition to the combination of surgery with chemotherapy in tumour treatment.