Gene-selective transcription promotes the inhibition of tissue reparative macrophages by TNF

Anti-TNF therapies are a core anti-inflammatory approach for chronic diseases such as rheumatoid arthritis and Crohn’s Disease. Previously, we and others found that TNF blocks the emergence and function of alternative-activated or M2 macrophages involved in wound healing and tissue-reparative functions. Conceivably, anti-TNF drugs could mediate their protective effects in part by an altered balance of macrophage activity. To understand the mechanistic basis of how TNF regulates tissue-reparative macrophages, we used RNAseq, scRNAseq, ATACseq, time-resolved phospho-proteomics, gene-specific approaches, metabolic analysis, and signaling pathway deconvolution. We found that TNF controls tissue-reparative macrophage gene expression in a highly gene-specific way, dependent on JNK signaling via the type 1 TNF receptor on specific populations of alternative-activated macrophages. We further determined that JNK signaling has a profound and broad effect on activated macrophage gene expression. Our findings suggest that TNF’s anti-M2 effects evolved to specifically modulate components of tissue and reparative M2 macrophages and TNF is therefore a context-specific modulator of M2 macrophages rather than a pan-M2 inhibitor.

Macrophage Involvement in Medication-Related Osteonecrosis of the Jaw (MRONJ): A Comprehensive, Short Review

Antiresorptive agents such as bisphosphonates (BP) and denosumab are commonly prescribed for the management of primary bone malignancy, bone metastasis, osteoporosis, Paget disease, or other bone disorders. Medication-related osteonecrosis of the Jaws (MRONJ) is a rare but significant complication of antiresorptive medications. Duration, dose, and antiresorptive potency as well as concomitant diseases, additional medications, and local factors affect MRONJ incidence and severity. MRONJ pathophysiology is still poorly understood. Nevertheless, decreased bone resorption due to osteoclastic inhibition along with trauma, infection/inflammation, or blood supply inhibition are considered synergistic factors for disease development. In addition, previous data research examined the effects of antiresorptive medication on immune system components and introduced potential alterations on immune response as novel elements in MRONJ pathogenesis. Considering that macrophages are the first cells in the nonspecific immune response, it is not surprising that these multifaceted players attracted increased attention in MRONJ research recently. This current review attempted to elucidate the effects of antiresorptive medications on several aspects of macrophage activity in relation to the complex inflammatory microenvironment of MRONJ. Collectively, unravelling the mode of action and extent of macrophages’ potential contribution in MRONJ occurrence will provide novel insight in disease pathogenesis and potentially identify intrinsic therapeutic targets.

Effects of thymulin 5cH in granuloma evolution and B1 cell differentiation: an experimental model to understand its biological mechanisms

In previous studies, we found that thymulin (a thymic hormone), when prepared in homeopathic 5cH potency, had the property to improve the productive performance of broiler chickens infected with reovirus, as well as modulate the development of Ehrlich tumor and granuloma inflammatory lesions in mice by immune-mediated mechanisms. The aim of the present work was to study the immunomodulatory mechanisms of thymulin 5cH in a granuloma experimental model, by subcutaneous inoculation of BCG in mice, focusing the B-1 cells and zinc involvement in this process. Three groups of male Balb/c SPF mice (group A treated with thymulin 5cH, group B treated with thymulin 5cH incubated in Chelex ® - a zinc chelant - and group C, control, treated with vehicle) were inoculated with BCG in the left footpad and subcutaneous granuloma and spleen were harvested for histomorphometry analysis, after 7, 14 and 21 days. Ziehl-Neelsen, HE and Prussia Blue staining methods were used. Flow cytometry was also used in the same times to characterize and quantify peritoneal cells. Positive cells for CD11b (activated phagocytes, B-1 cells), CD19 (B-1 and B-2 cells), CD23 (negative B-1 cells, positive B2 cells) and CD5 (B-1a cells) were analyzed in a FACS Calibur (BD) device. Statistical analysis was performed using Kruskal - Wallis / Dunn for nonparametric evaluations and ANOVA / Tuckey-Krammer for the parametric ones. The X² method was used to evaluate the cell count in flow cytometry. P values ≤ 0.05 were considered statistically significant. Mice treated with thymulin 5cH presented higher macrophage activity and increase in the follicular area were seen in spleen after 7 days. Increase in gross lesion diameter and decrease in local BCG infection were seen after 21 days. At this time, the flow cytometry demonstrated the increase in peritoneal phagocytes derived from B-1 cells in thymulin 5cH treated mice, independently of Chelex ® incubation. The incubation of thymulin 5cH with Chelex ® blocked its effects only upon the number of B2 cells in the peritoneum and reduces Mn levels in the medicine solution. We conclude that thymulin 5CH modulates the BCG-induced granuloma through more than one mechanism, especially by peritoneal B1 cell differentiation into phagocytes.

Inflammatory Cell Composition and Immune-Related microRNA Signature of Temporal Artery Biopsies From Patients With Giant Cell Arteritis

ObjectivesThe aim of this study was to quantitatively assess distinct immune cell subsets comprising inflammatory infiltrate in temporal artery biopsies (TABs) from patients with giant cell arteritis (GCA), and to link the obtained histopathological data with expression profiles of immune-related microRNAs (miRNAs).MethodsThe study included 68 formalin-fixed, paraffin-embedded TABs from treatment-naïve patients, including 30 histologically positive GCA and 16 negative GCA TABs, and 22 control non-GCA TABs. Quantitative assessment of histological parameters was performed using histopathological and immunohistochemical techniques. miRNA expression analysis was performed by quantitative real-time PCR.ResultsIntense transmural mononuclear inflammatory infiltrates in TAB-positive GCA arteries were predominantly composed of CD3+, CD4+ and CD8+ T lymphocytes, and CD68+ macrophages, accompanied by a strong nuclear overexpression of the nuclear factor of activated T cells, cytoplasmic 1 (NFATC) in the lymphocyte infiltrate fraction. Furthermore, TAB-positive GCA arteries were characterized by significant overexpression of nine pro-inflammatory miRNAs (miR-132-3p/-142-3p/-142-5p/-155-5p/-210-3p/-212-3p/-326/-342-5p/-511-5p) and a significant under-expression of six regulatory immune-related miRNAs (miR-30a-5p/-30b-5p/-30c-5p/-30d-5p/-30e-5p/-124-3p), whose expression levels significantly associated with most evaluated histopathological parameters. Notably, we revealed miR-132-3p/-142-3p/-142-5p/-155-5p/-212-3p/-511-5p as major promoters of arterial inflammation and miR-30a-5p/-30c-5p/-30d-5p as putative regulators of NFATC signaling in TAB-positive GCA arteries.ConclusionOverall, we demonstrated that an altered arterial tissue-specific pro-inflammatory miRNA signature favors enhanced T cell-driven inflammation and macrophage activity in TAB-positive GCA arteries. Moreover, dysregulation of several immune-related miRNAs seems to contribute crucially to GCA pathogenesis, through impairing their regulatory activity towards T cell-mediated immune responses driven by the calcineurin (CaN)/NFAT signaling pathway, indicating their therapeutic, diagnostic and prognostic potential.

Metformin for Tuberculosis Infection

Tuberculosis, caused by Mycobacterium tuberculosis (M.tb), remains the biggest infection burden in the word. Rifampin (RIF) and Isoniazid (INH) are the most effective antibiotics for killing M.tb. However, the resistance rate of rifampin and INH are high and lead to almost 35% treatment failure. Metformin enhanced anti tuberculosis efficacy in killing M. tuberculosis through several mechanism, firstly through autophagia mechanism and secondly by activating superoxide dismutase (SOD). Metformin activated mTOR and AMPK then induced more effective autophagy against M.tb. Superoxide Dismutase (SOD) is an enzyme produced in the host’s antioxidant defense system. SOD neutralizes reactive oxygen species (ROS) that excessively produced during phagocytosis process against M.tb. Excessive production of ROS associated with Th1 overactivation and leads into macrophage activity inhibition and excessive tissue damage. Metformin has ability in improving SOD level during inflammation.

Effect of Reducing Inflammation of Coptis chinensis Extract -Ceramide Complex through ECS Control in Atopic Dermatitis

Objectives: The purpose of this study was to confirm effect of reducing inflammation of Coptis chinensis extract -ceramide complex through the endocannabinoid system (ECS) control in atopic dermatitis.Methods: 8-week-old ICR mice were divided into normal group (Ctrl), lipid barrier elimination group (ADE), palmitoylethanolamide treated group after lipid barrier elimination (PEAT), and Coptis chinensis extract-ceramide complex applied group after lipid barrier elimination (CRA). After inducing atopic dermatitis, cannabinoid receptor (CB) 1, CB2, CD68, p-IκB, iNOS, substance P and serotonin were observed to confirm the regulation of the ECS, macrophage activity and mast cell activity.Results: CB1 and CB2 showed higher positive reactions in the CRA than in the ADE and PEAT. CD68, p-IκB and iNOS showed higher positive reaction in the ADE, PEAT and CRA than in the Ctrl, but the increase in the positive reaction was lower in the CEA compared to the ADE and PEAT. Substance P and serotonin showed higher positive reaction in the ADE, PEAT and CRA than in the Ctrl, but the increase in the positive reaction was lower in the CEA compared to the ADE and PEAT.Conclusions: The effects of Coptis chinensis extract -ceramide complex were confirmed on the regulation of the ECS, macrophage activity and mast cell activity.

Characterization and Heterologous Expression of UDP-Glucose 4-Epimerase From a Hericium erinaceus Mutant with High Polysaccharide Production

Hericium erinaceus is an important medicinal fungus in traditional Chinese medicine because of its polysaccharides and other natural products. Compared terpenoids and polyketides, the analysis of synthetic pathway of polysaccharides is more difficult because of the many genes involved in central metabolism. In previous studies, A6180, encoding a putative UDP-glucose 4-epimerase (UGE) in an H. erinaceus mutant with high production of active polysaccharides, was significantly upregulated. Since there is no reliable genetic manipulation technology for H. erinaceus, we employed Escherichia coli and Saccharomyces cerevisiae to study the function and activity of A6180. The recombinant overexpression vector pET22b-A6180 was constructed for heterologous expression in E. coli. The enzymatic properties of the recombinant protein were investigated. It showed that the recombinant A6180 could strongly convert UDP-α-D-glucose into UDP-α-D-galactose under optimal conditions (pH 6.0, 30°C). In addition, when A6180 was introduced into S. cerevisiae BY4742, xylose was detected in the polysaccharide composition of the yeast transformant. This suggested that the protein coded by A6180 might be a multifunctional enzyme. The generated polysaccharides with a new composition of sugars showed enhanced macrophage activity in vitro. These results indicate that A6180 plays an important role in the structure and activity of polysaccharides. It is a promising strategy for producing polysaccharides with higher activity by introducing A6180 into polysaccharide-producing mushrooms.

The Effects of Microtubule Stabilizing Drugs on Macrophage Immune-Mediated Endocytosis

<p>Microtubule stabilizing drugs (MSD) bind and stabilize microtubules, thus inhibiting their normal function. MSD exhibit anti-mitotic effects which makes them attractive as cancer chemotherapeutics and much of existing research has focused on these effects in proliferating cells. In contrast, we are interested in assessing the effects of microtubule stabilization on non-proliferating cells, such as macrophages, to determine potential mitosis-independent actions of MSD on microtubule function. Thus, we investigated the effects of MSD on macrophage receptor-mediated endocytosis of low density lipoproteins (LDL) and found no significant effect on the ability of paclitaxel-treated macrophages to endocytose LDL. Alterations to macrophage phagocytic and killing efficiency due to treatment with paclitaxel, peloruside or docetaxel, as well as the recently discovered compounds, ixabepilone, mycothiazole, and zampanolide were investigated. Treatment with paclitaxel, peloruside or docetaxel did not significantly inhibit phagocytosis or killing of bacteria. Results from confocal microscopy suggest that paclitaxel alters phagocytic kinetics in macrophages. Respectively, zampanolide and mycothiazole significantly inhibited macrophage bactericidal and killing ability, while Ixabepilone enhanced bacterial killing. MSD treatment also altered production of tumor necrosis factor alpha (TNF-a) and nitric oxide (NO) during bacterial killing. Optimal activation of macrophages with IFN-y did not alter the effects of MSD. Taken together, these results suggest that MSD have multiple immunomodulatory effects unrelated to their anti-mitotic effects. The data suggests that during MSD treatment, macrophage activity maybe altered or impaired, thus modifying the ability of patients to fight off bacterial infections.</p>