Network pharmacology analysis and experimental validation of Xiao-Qing-Long-Tang's therapeutic effects against neutrophilic asthma.

BACKGROUND: Xiao-Qing-Long-Tang (XQLT), a classical Chinese herbal medicine formula, has been extensively used for allergic asthma treatment. However, there is limited research on its anti-inflammatory effects and mechanisms specifically in neutrophilic asthma (NA). PURPOSE: This study aims to investigate the potential therapeutic effects of XQLT against NA using a combination of network pharmacology and experimental validation. STUDY DESIGN: By utilizing traditional Chinese medicine and disease databases, we constructed an XQLT-asthma network to identify potential targets of XQLT for NA. In the experimental phase, we utilized an ovalbumin (OVA)/lipopolysaccharide (LPS)-induced model for neutrophilic asthma and examined the therapeutic effects of XQLT. RESULTS: Our research identified 174 bioactive components within XQLT and obtained 140 target genes of XQLT against asthma. Functional enrichment analysis revealed that these target genes were primarily associated with inflammation and cytokines. In the experimental validation, mice induced with OVA-LPS showcased eosinophilic and neutrophilic cell infiltration in peri-bronchial areas, elevated levels of IL-4 and IL-17 in both serum and lung, increased percentages of Th2 and Th17 cells in the spleen, as well as elevated levels of CD11b+ and CD103+ dendritic cells (DCs) within the lung. Treatment with XQLT effectively reduced IL-4 and IL-17 levels, decreased the percentages of Th2, Th17, CD11b+, and CD103+ DCs, and improved inflammatory cell infiltrations in lung tissues. These findings serve as a foundation for the potential clinical application of XQLT in neutrophilic asthma.

Effects of Aeriscardovia aeriphila on growth performance, antioxidant functions, immune responses, and gut microbiota in broiler chickens. / Aeriscardovia aeriphilaå¯¹è‚‰é¸¡ç”Ÿé•¿æ€§èƒ½ã€æŠ—æ°§åŒ–åŠŸèƒ½ã€å ç–«åº”ç­”å’Œè‚ é“èŒç¾¤çš„å½±å“.

Aeriscardovia aeriphila, also known as Bifidobacterium aerophilum, was first isolated from the caecal contents of pigs and the faeces of cotton-top tamarin. Bifidobacterium species play important roles in preventing intestinal infections, decreasing cholesterol levels, and stimulating the immune system. In this study, we isolated a strain of bacteria from the duodenal contents of broiler chickens, which was identified as A. aeriphila, and then evaluated the effects of A. aeriphila on growth performance, antioxidant functions, immune functions, and gut microbiota in commercial broiler chickens. Chickens were orally gavaged with A. aeriphila (1×109 CFU/mL) for 21 d. The results showed that A. aeriphila treatment significantly increased the average daily gain and reduced the feed conversion ratio (P<0.001). The levels of serum growth hormone (GH) and insulin-like growth factor 1 (IGF-1) were significantly increased following A. aeriphila treatment (P<0.05). Blood urea nitrogen and aspartate aminotransferase levels were decreased, whereas glucose and creatinine levels increased as a result of A. aeriphila treatment. Furthermore, the levels of serum antioxidant enzymes, including catalase (P<0.01), superoxide dismutase (P<0.001), and glutathione peroxidase (P<0.05), and total antioxidant capacity (P<0.05) were enhanced following A. aeriphila treatment. A. aeriphila treatment significantly increased the levels of serum immunoglobulin A (IgA) (P<0.05), IgG (P<0.01), IgM (P<0.05), interleukin-1 (IL-1) (P<0.05), IL-4 (P<0.05), and IL-10 (P<0.05). The broiler chickens in the A. aeriphila group had higher secretory IgA (SIgA) levels in the duodenum (P<0.01), jejunum (P<0.001), and cecum (P<0.001) than those in the control group. The messenger RNA (mRNA) relative expression levels of IL-10 (P<0.05) and IL-4 (P<0.001) in the intestinal mucosa of chickens were increased, while nuclear factor-|κB (NF|-|κB) (P<0.001) expression was decreased in the A. aeriphila group compared to the control group. Phylum-level analysis revealed Firmicutes as the main phylum, followed by Bacteroidetes, in both groups. The data also found that Phascolarctobacterium and Barnesiella were increased in A. aeriphila-treated group. In conclusion, oral administration of A. aeriphila could improve the growth performance, serum antioxidant capacity, immune modulation, and gut health of broilers. Our findings may provide important information for the application of A. aeriphila in poultry production.

Anandamide improves food intake and orexinergic neuronal activity in the chronic sleep deprivation induction model in rats by modulating the expression of the CB1 receptor in the lateral hypothalamus.

Sleep deprivation alters orexinergic neuronal activity in the lateral hypothalamus (LH), which is the main regulator of sleep-wake, arousal, appetite, and energy regulation processes. Cannabinoid receptor (CBR) expression in this area is involved in modulating the function of orexin neurons. In this study, we investigated the effects of endocannabinoid anandamide (AEA) administration on improving food intake and appetite by modulating the activity of orexin neurons and CB1R expression after chronic sleep deprivation. Adult male Wistar rats (200-250 g) were randomly divided into three groups: control + vehicle (Control), chronic sleep deprivation + vehicle (SD), and chronic sleep deprivation +20 mg/kg AEA (SD + A). For SD induction, the rats were kept in a sleep deprivation device for 18 h (7 a.m. to 1 a.m.) daily for 21 days. Weight gain, food intake, the electrical power of orexin neurons, CB1R mRNA expression in hypothalamus, CB1R protein expression in the LH, TNF-α, IL-6, IL-4 levels and antioxidant activity in hypothalamus were measured after SD induction. Our results showed that AEA administration significantly improved food intake (p < 0.01), Electrical activity of orexin neurons (p < 0.05), CB1R expression in the hypothalamus (p < 0.05), and IL-4 levels (p < 0.05). AEA also reduced mRNA expression of OX1R and OX2R (p < 0.01 and p < 0.05 respectively), also IL-6 and TNF-α (p < 0.01) and MDA level (p < 0.05) in hypothalamic tissue. As a consequence, AEA modulates orexinergic system function and improves food intake by regulating the expression of the CB1 receptor in the LH in sleep deprived rats.

Garcinone E suppresses breast cancer growth and metastasis by modulating tumor-associated macrophages polarization via STAT6 signaling.

Cancer metastasis remains the most common cause of death in breast cancer patients. Tumor-associated macrophages (TAMs) are a novel therapeutic target for the treatment of metastatic breast cancer. Despite the good anti-cancer activity of garcinone E (GE), there are no reports on its therapeutic effects on breast cancer metastasis. The objective of this study was to examine the anti-cancer effects of GE on metastatic breast cancer. RAW 264.7 and THP-1 cells were polarized to M2 macrophages by IL-4/IL-13 in vitro. A 4T1 mouse breast cancer model and the tail vein breast cancer metastasis model were used to explore the effect of GE on breast cancer growth and metastasis in vivo. In vitro studies showed that GE dose-dependently suppressed IL-4 + IL-13-induced expression of CD206 in both RAW 264.7 cells and differentiated THP-1 macrophages. However, GE did not affect the LPS + IFN-γ-induced polarization to the M1-like macrophages in vitro. GE inhibited the expression of the M2 macrophage specific genes in RAW 264.7 cells, and simultaneously impaired M2 macrophage-induced breast cancer cell proliferation and migration, and angiogenesis. In animal studies, GE significantly suppressed tumor growth, angiogenesis, and lung metastasis in 4T1 tumor-bearing mice, without causing toxicity. In both tumor and lung tissues, the proportion of M2-like TAMs was significantly decreased while the proportion of M1-like TAMs was markedly increased by GE treatment. Mechanistically, GE inhibited phosphorylation of STAT6 in vitro and in vivo. Our results demonstrate for the first time that GE suppresses breast cancer growth and pulmonary metastasis by modulating M2-like macrophage polarization through the STAT6 signaling pathway.

Chinese herbal compound Huangqin Qingrechubi capsule reduces lipid metabolism disorder and inflammatory response in gouty arthritis via the LncRNA H19/APN/PI3K/AKT cascade.

CONTEXT: Gouty arthritis (GA) is a characteristically inflammatory disease often associated with lipid metabolism disorder. Huangqin Qingrechubi capsule (HQC) has been used for the treatment of GA. OBJECTIVE: To explore the mechanism of HQC in the treatment of GA. MATERIALS AND METHODS: A total of 30 GA patients (GA group) and 30 healthy subjects [normal control (NC) group] were recruited. The GA group was treated with HQC (3.6 g/d) for 10 days. Lipid metabolism and inflammation indexes were detected. Five herbal names of HQC, or 'gouty arthritis', 'hyperlipidemia' and 'inflammation' were used as key words to search related databases for network pharmacological analysis. Subsequently, GA-fibroblast-like synoviocytes (FLSs) were stimulated with GA-peripheral blood mononuclear cells (PBMCs) (3:1) and treated with HQC drug-containing serum (20%). RT-qPCR, Western blot, and ELISA were conducted to further explore the mechanism of HQC in improving GA. RESULTS: In clinical observation, HQC decreased the expression of lncRNA H19 and IL-1ß, and increased the expression of adiponectin (APN) and IL-4 in the GA group (about half). Through network pharmacology, the PI3K/AKT signaling pathway was identified. Cell experiments showed that HQC treatment reduced the viability of GA-FLSs (49.61%), up-regulated the expression of IL-4 (155.18%), IL-10 (165.13%), and APN (31.24%), and down-regulated the expression of lncRNA H19 (33.70%), IL-1ß (64.70%), TNF-α (78.32%), p-PI3K (48.80%), and p-AKT (53.48%). DISCUSSION AND CONCLUSIONS: HQC improved lipid metabolism disorder and inflammatory response of GA by regulating the lncRNA H19/APN/PI3K/AKT. Maintaining the stability of lipid metabolism may be an effective way to alleviate GA.

Regulation of ferroptosis and ACSL4-15LO1 pathway contributed to the anti-asthma effect of acupuncture.

Acupuncture has been frequently used in China for the treatment asthma for thousands of years. Ferroptosis was recently revealed to be involved in several pathological conditions including asthma. However, the detailed links between ferroptosis and airway inflammation in asthma, as well as the detailed regulation of acupuncture on these disorders remains unclear. Our results demonstrated that the non-haem Fe2+ level increased markedly in the lung tissue of mouse asthma model, and positively correlated with RL and IL-4 level in BALF. Furthermore, lipid peroxidation markers MDA and GSSG increased remarkably in OVA-induced experimental asthma mice. Up-regulation of lipid peroxidation associated proteins ACSL4 and15-LO1 was also observed in OVA-induced experimental asthma mice. To demonstrate the role of ferroptosis in asthma and the effect of acupuncture on these disorders, ferroptosis-induction agent erastin and ferroptosis-inhibition agent fer-1 were used, and our data demonstrated that erastin could augment lung inflammation and lipid peroxidation in OVA induced asthma model. Fer-1 was able to relieve AHR, lung inflammation, non-haem Fe2+ level, lipid peroxidation and ferroptosis related pathway ACSL4-15LO1 in OVA-induced experimental asthma mice. Acupuncture treatment alleviated RL, lung inflammation as well as type 2 cytokines IL-4 and IL-13 levels induced by OVA inhalation. What's more, acupuncture significantly reduced the MDA and GSSG levels, the non-haem Fe2+ level and ACSL4-15-LO1 proteins expression. Acupuncture also relieved erastin-induced exacerbation in lung inflammation and lipid peroxidation in ferroptosis. Acupuncture treatment could relieve ferroptosis related exacerbation in airway inflammation. Our study provided insights into the underlying mechanisms for the protective effects of acupuncture and highlighted a therapeutic potential of acupuncture treatment in the attenuation of lipid peroxidation and ferroptosis in asthma.

Antiallergic Effects of N,N-dicoumaroylspermidine Isolated from Lithospermum erythrorhizon on Mast Cells and Ovalbumin-Induced Allergic Rhinitis.

In East Asia, the dried root of Lithospermum erythrorhizon has been utilized as an anti-inflammatory, antipyretic, detoxifying, and anti-inflammatory agent. Recently, we reported that L. erythrorhizon protects against allergic rhinitis; however, the component within L. erythrorhizon that exerts antiallergic activity remains unknown. The purpose of the current study was to isolate and characterize the antiallergic active components in an ethanolic extract of L. erythrorhizon roots. We examined the antiallergic effects of L. erythrorhizon reflux ethanol extracts in an ovalbumin (OVA)-induced allergic rhinitis mouse model, and compared the chemical compounds extracted using the hot reflux and cold extraction methods. Chromatographic separation identified two novel anthraquinones, erythrin A and B, one newly discovered compound from the Lithospermum genus, N1″,N3″-dicoumaroylspermidine, and nineteen other recognized compounds. Their chemical structures were elucidated by single (1D) and 2D analysis of nuclear magnetic resonance (NMR) spectroscopic data, as well as high resolution mass spectrometry. Among the identified compounds, N,N'-dicoumaroylspermidine strongly inhibited the release of ß-hexosaminidase, as well as the production of IL-3, IL-4, and IL-13 by IgE-sensitized and BSA-stimulated RBL-2H3 cells. Using the OVA-induced allergic rhinitis mouse model, we showed that N,N'-dicoumaroylspermidine reduced the production of serum OVA-specific IgE and the number of inflammatory cells in nasal lavage fluid. N,N'-dicoumaroylspermidine isolated from L. erythrorhizon exhibits antiallergic properties, making it potentially effective for allergic rhinitis.

Unveiling the Ability of Witch Hazel (Hamamelis virginiana L.) Bark Extract to Impair Keratinocyte Inflammatory Cascade Typical of Atopic Eczema.

Hamamelis virginiana L. bark extract is a traditional remedy for skin affections, including atopic dermatitis/eczema (AD). Hamamelis preparations contain tannins, including hamamelitannin (HT), although their pharmacological role in AD is still unknown. This study aimed to study the rational for its topical use by considering the impact of crucial biomarkers on AD pathogenesis. A standardized extract (HVE) (0.5−125 µg/mL) was compared to hamamelitannin (HT), its main compound (0.5−5 µg/mL), in a model of human keratinocytes (HaCaTs), challenged with an AD-like cytokine milieu (TNF-α, IFN-γ, and IL-4). HVE inhibited the release of mediators involved in skin autoimmunity (IL-6 and IL-17C) and allergy (TSLP, IL-6, CCL26, and MMP-9) with a concentration-dependent fashion (IC50s < 25 µg/mL). The biological mechanism was ascribed, at least in part, to the impairment of the NF-κB-driven transcription. Moreover, HVE counteracted the proliferative effects of IL-4 and recovered K10, a marker of skin differentiation. Notably, HT showed activity on well-known targets of IL-4 pathway (CCL26, K10, cell proliferation). To the best of our knowledge, this work represents the first demonstration of the potential role of Hamamelis virginiana in the control of AD symptoms, such as itch and skin barrier impairment, supporting the relevance of the whole phytocomplex.

Oxysophocarpine inhibits airway inflammation and mucus hypersecretion through JNK/AP-1 pathway in vivo and in vitro.

Asthma is a high-incidence disease in the world. Oxysophocarpine (OSC), a quinolizidine alkaloid displays various pharmacological functions including anti-inflammation, neuroprotective, anti-virus and antioxidant. Here, we established mice and cell asthmatic model to explore the effects of OSC for asthma treatment. Mice were sensitized and challenged with ovalbumin (OVA) and treated with OSC before challenge. Enzyme-linked immuno sorbent assay (ELISA), hematoxylin and eosin (H&E), periodic acid-schiff (PAS), tolonium chloride staining and immunohistochemical assay were performed. OSC treatment inhibited inflammatory cell infiltration and mucus secretion in the airway, reduced IgE level in mouse serum and decreased IL-4, IL-5 production in bronchoalveolar lavage fluid (BALF). OSC also reduced the spleen index to regulate immune function. Meanwhile, NCI-H292 cells were induced by lipopolysaccharide (LPS) to simulate airway epithelial injury. OSC pretreatment decreased the IL-6 and IL-8 cytokine levels, mucin 5 AC expression, and mucin 5 AC mRNA level in the cell model. Further, OSC suppressed the phosphorylation of c-Jun N-terminal kinase (JNK), and activator protein 1 (AP-1, Fos and Jun). These findings revealed that OSC alleviated bronchial asthma associated with JNK/AP-1 signaling pathway.

Potential Anti-allergic Effects of Bibenzyl Derivatives from Liverworts, Radula perrottetii.

The liverwort Radula perrottetii contains various bibenzyl derivatives which are known to possess various biological activities, such as anti-inflammatory effects. Mast cells (MC) play crucial roles in allergic and inflammatory diseases; thus, inhibition of MC activation is pivotal for the treatment of allergic and inflammatory disorders. We investigated the effects of perrottetin D (perD), isolated from Radula perrottetii, and perD diacetate (Ac-perD) on antigen-induced activation of MCs. Bone marrow-derived MCs (BMMCs) were generated from C57BL/6 mice. The degranulation ratio, histamine release, and the interleukin (IL)-4 and leukotriene B4 productions on antigen-triggered BMMC were investigated. Additionally, the effects of the bibenzyls on binding of IgE to FcεRI were observed by flow cytometry, and signal transduction proteins was examined by Western blot. Furthermore, binding of the bibenzyls to the Fyn kinase domain was calculated. At 10 µM, perD decreased the degranulation ratio (p < 0.01), whereas 10 µM Ac-perD down-regulated IL-4 production (p < 0.05) in addition to decreasing the degranulation ratio (p < 0.01). Both compounds tended to decrease histamine release at a concentration of 10 µM. Although 10 µM perD reduced only Syk phosphorylation, 10 µM Ac-perD diminished phosphorylation of Syk, Gab2, PLC-γ, and p38. PerD appeared to selectively bind Fyn, whereas Ac-perD appeared to act as a weak but broad-spectrum inhibitor of kinases, including Fyn. In conclusion, perD and Ac-perD suppressed the phosphorylation of signal transduction molecules downstream of the FcεRI and consequently inhibited degranulation, and/or IL-4 production. These may be beneficial potential lead compounds for the development of novel anti-allergic and anti-inflammatory drugs.

Effective-compound combination inhibits the M2-like polarization of macrophages and attenuates the development of pulmonary fibrosis by increasing autophagy through mTOR signaling.

BACKGROUND AND PURPOSE: The M2 polarization of macrophages substantially contributes to the progression of pulmonary fibrosis (PF). Effective-compound combination (ECC), which is composed of isoliquiritigenin, icariin, nobiletin, peimine, and paeoniflorin, ameliorated bleomycin-induced PF in rats. Hence, we investigated the anti-PF mechanism of ECC with a focus on the suppression of M2 polarization in macrophages in vivo and in vitro. METHODS: The PF rat model was generated via the intratracheal instillation of bleomycin. Histological changes, M2 macrophages, and profibrotic mediators were detected. The M2 polarization model was generated by incubating macrophages with IL-4. Quantitative PCR and Western blotting were used to measure mRNA and protein levels, respectively. RESULTS: ECC attenuated bleomycin-induced PF in rats, which might be associated with reduced macrophage infiltration, M2 polarization, and profibrotic mediator expression. Furthermore, ECC significantly suppressed M2 polarization in IL-4-treated macrophages, which was accompanied by the upregulation of autophagy. An autophagy inhibitor abrogated the inhibitory effect of ECC on M2 polarization. In addition, ECC decreased the levels of p-p70S6K/p-4EBP and p-AKT473/p-GSK3ß, which are critical regulators of autophagy. CONCLUSION: ECC can ameliorate PF, which might be associated with the inhibition of M2 polarization through the promotion of autophagy via mTOR signaling suppression.

Pinosylvin Shifts Macrophage Polarization to Support Resolution of Inflammation.

Pinosylvin is a natural stilbenoid found particularly in Scots pine. Stilbenoids are a group of phenolic compounds identified as protective agents against pathogens for many plants. Stilbenoids also possess health-promoting properties in humans; for instance, they are anti-inflammatory through their suppressing action on proinflammatory M1-type macrophage activation. Macrophages respond to environmental changes by polarizing towards proinflammatory M1 phenotype in infection and inflammatory diseases, or towards anti-inflammatory M2 phenotype, mediating resolution of inflammation and repair. In the present study, we investigated the effects of pinosylvin on M2-type macrophage activation, aiming to test the hypothesis that pinosylvin could polarize macrophages from M1 to M2 phenotype to support resolution of inflammation. We used lipopolysaccharide (LPS) to induce M1 phenotype and interleukin-4 (IL-4) to induce M2 phenotype in J774 murine and U937 human macrophages, and we measured expression of M1 and M2-markers. Interestingly, along with inhibiting the expression of M1-type markers, pinosylvin had an enhancing effect on the M2-type activation, shown as an increased expression of arginase-1 (Arg-1) and mannose receptor C type 1 (MRC1) in murine macrophages, and C-C motif chemokine ligands 17 and 26 (CCL17 and CCL26) in human macrophages. In IL-4-treated macrophages, pinosylvin enhanced PPAR-γ expression but had no effect on STAT6 phosphorylation. The results show, for the first time, that pinosylvin shifts macrophage polarization from the pro-inflammatory M1 phenotype towards M2 phenotype, supporting resolution of inflammation and repair.

Inflammatory response under zinc deficiency is exacerbated by dysfunction of the T helper type 2 lymphocyte-M2 macrophage pathway.

Nutritional zinc deficiency leads to immune dysfunction and aggravates inflammation. However, the underlying mechanism remains unknown. In this study, the relationship between macrophage subtypes (M1 and M2) and helper T lymphocytes (Th1 and Th2) was investigated using the spleen from rats fed zinc-deficient or standard diet. In experiment I, 5-week-old male Sprague-Dawley rats were fed a zinc-deficient diet (without zinc additives) or a standard diet (containing 0·01% zinc) for 6 weeks. In experiment II, the rats were divided into four groups: one group was fed a standard diet for 6 weeks; two groups were fed zinc-deficient diets and were injected three times a week with either saline or interleukin-4 (IL-4) (zinc-deficient/IL-4 i.p.); a fourth group (zinc-deficient/standard) was fed a zinc-deficient diet for 6 weeks followed by a standard diet for 4 weeks. In experiment I; GATA-binding protein 3 (GATA-3) protein level, M2 macrophage, CD3+  CD8+ cells, and IL-4/IL-13-positive cells significantly decreased in the spleens of the zinc-deficient group. Additionally, IL-1ß and macrophage inflammatory protein-1α (MIP-1α) mRNA levels significantly increased in the splenic macrophages of the zinc-deficient group. In experiment II; M2 macrophages, CD3+  CD8+ cells, IL-4/IL-13-positive cells, and GATA-3 protein levels significantly increased in the spleens of the zinc-deficient/IL-4 i.p. and zinc-deficient/standard groups. Furthermore, IL-1ß and MIP-1α mRNA levels decreased in the splenic macrophages of the zinc-deficient/IL-4 i.p. and zinc-deficient/standard groups. Zinc deficiency-induced aggravated inflammation is related to Th2 lymphocytes and followed by the association with loss of GATA-3, IL-4 and anti-inflammatory M2 macrophages. Importantly, IL-4 injection or zinc supplementation can reverse the effects of zinc deficiency on immune function.

IL-33 modulates inflammatory brain injury but exacerbates systemic immunosuppression following ischemic stroke.

Stroke triggers a complex inflammatory process in which the balance between pro- and antiinflammatory mediators is critical for the development of the brain infarct. However, systemic changes may also occur in parallel with brain inflammation. Here we demonstrate that administration of recombinant IL-33, a recently described member of the IL-1 superfamily of cytokines, promotes Th2-type effects following focal ischemic stroke, resulting in increased plasma levels of Th2-type cytokines and fewer proinflammatory (3-nitrotyrosine+F4/80+) microglia/macrophages in the brain. These effects of IL-33 were associated with reduced infarct size, fewer activated microglia and infiltrating cytotoxic (natural killer-like) T cells, and more IL-10-expressing regulatory T cells. Despite these neuroprotective effects, mice treated with IL-33 displayed exacerbated post-stroke lung bacterial infection in association with greater functional deficits and mortality at 24 hours. Supplementary antibiotics (gentamicin and ampicillin) mitigated these systemic effects of IL-33 after stroke. Our findings highlight the complex nature of the inflammatory mechanisms differentially activated in the brain and periphery during the acute phase after ischemic stroke. The data indicate that a Th2-promoting agent can provide neuroprotection without adverse systemic effects when given in combination with antibiotics.

Porphyromonas gingivalis inhibits M2 activation of macrophages by suppressing α-ketoglutarate production in mice.

Reprograming of metabolic pathways is critical in governing the polarization of macrophages into classical proinflammatory M1 or alternative anti-inflammatory M2 phenotypes in metabolic diseases, such as diabetes. Porphyromonas gingivalis, a keystone pathogen of periodontitis, causes an imbalance in M1/M2 activation, resulting in a hyperinflammatory environment that promotes the pathogenesis of periodontitis. However, whether P. gingivalis infection modulates metabolic pathways to alter macrophage polarization remains unclear. Bone-marrow-derived macrophages (BMDMs) were collected from 6-week-old female C57BL/6 mice and stimulated with P. gingivalis, P. gingivalis-derived LPS or IL-4. Relative gene expression and protein production were measured by quantitative real-time PCR, RNA sequencing and western blotting. Colorimetric assays were also performed to assess the amounts of α-ketoglutarate (α-KG) and succinate. P. gingivalis or P. gingivalis-derived LPS-induced inflammatory responses enhanced M1 macrophages and suppressed M2 macrophages, even in the presence of IL-4. P. gingivalis inhibited Idh1/2 and Gpt1/2 mRNA expression, and increased Akgdh mRNA expression, thus decreasing the ratio of α-KG/succinate. Supplementation of cell-permeable dimethyl-α-KG dramatically restored M2 activation during P. gingivalis infection. Our study suggests that P. gingivalis maintains a hyperinflammatory state by suppressing the production of α-KG by M2 macrophages.

Antibody-based targeted delivery of interleukin-4 synergizes with dexamethasone for the reduction of inflammation in arthritis.

Objectives: We have previously reported that F8-IL4, a fusion protein consisting of the F8 antibody specific to the alternatively-spliced extra domain A of fibronectin and of murine IL-4, cures mice with established arthritis, when used in combination with dexamethasone (DXM). The goal of this study was to assess whether other therapeutic agents, besides DXM, could induce cures in combination with F8-IL4 and to elucidate which leucocytes are most affected by the pharmacological treatment. Methods: We performed therapy experiments in mice with CIA, using intravenous administrations of F8-IL4 in combination with DXM, MTX, murine cytotoxic T-lymphocyte-associated protein 4 fused to the fragment crystallizable portion of murine IgG2a, as well as mAbs to murine IL17A or the p40 subunit of murine IL12/IL23. Histology and immunohistochemistry for the identification of the various leucocytes were performed on the paws of mice euthanized at different therapy time points. Results: Only the use of F8-IL4 in combination with DXM induced complete remissions, while all other combinations did not lead to cures. The light microscopical evaluation of paws with arthritis revealed a predominant infiltration of neutrophils, which substantially decreased 24 h after treatment with F8-IL4 and DXM. Conclusion: The combination of F8-IL4 with DXM promotes a rapid anti-arthritic action by potently inhibiting neutrophil activity. A fully human analogue of F8-IL4 may find clinical utility for the treatment of neutrophil-driven chronic inflammatory conditions.

Protein arginine methyltransferase 1 modulates innate immune responses through regulation of peroxisome proliferator-activated receptor γ-dependent macrophage differentiation.

Arginine methylation is a common posttranslational modification that has been shown to regulate both gene expression and extranuclear signaling events. We recently reported defects in protein arginine methyltransferase 1 (PRMT1) activity and arginine methylation in the livers of cirrhosis patients with a history of recurrent infections. To examine the role of PRMT1 in innate immune responses in vivo, we created a cell type-specific knock-out mouse model. We showed that myeloid-specific PRMT1 knock-out mice demonstrate higher proinflammatory cytokine production and a lower survival rate after cecal ligation and puncture. We found that this defect is because of defective peroxisome proliferator-activated receptor γ (PPARγ)-dependent M2 macrophage differentiation. PPARγ is one of the key transcription factors regulating macrophage polarization toward a more anti-inflammatory and pro-resolving phenotype. We found that PRMT1 knock-out macrophages failed to up-regulate PPARγ expression in response to IL4 treatment resulting in 4-fold lower PPARγ expression in knock-out cells than in wild-type cells. Detailed study of the mechanism revealed that PRMT1 regulates PPARγ gene expression through histone H4R3me2a methylation at the PPARγ promoter. Supplementing with PPARγ agonists rosiglitazone and GW1929 was sufficient to restore M2 differentiation in vivo and in vitro and abrogated the difference in survival between wild-type and PRMT1 knock-out mice. Taken together these data suggest that PRMT1-dependent regulation of macrophage PPARγ expression contributes to the infection susceptibility in PRMT1 knock-out mice.

Anti-inflammatory effects of the petasin phyto drug Ze339 are mediated by inhibition of the STAT pathway.

Ze339, an herbal extract from Petasites hybridus leaves is effective in treatment of allergic rhinitis by inhibition of a local production of IL-8 and eicosanoid LTB4 in allergen-challenged patients. However, the mechanism of action and anti-inflammatory potential in virally induced exacerbation of the upper airways is unknown. This study investigates the anti-inflammatory mechanisms of Ze339 on primary human nasal epithelial cells (HNECs) upon viral, bacterial and pro-inflammatory triggers. To investigate the influence of viral and bacterial infections on the airways, HNECs were stimulated with viral mimics, bacterial toll-like-receptor (TLR)-ligands or cytokines, in presence or absence of Ze339. The study uncovers Ze339 modulated changes in pro-inflammatory mediators and decreased neutrophil chemotaxis as well as a reduction of the nuclear translocation and phosphorylation of STAT molecules. Taken together, this study suggests that phyto drug Ze339 specifically targets STAT-signalling pathways in HNECs and has high potential as a broad anti-inflammatory drug that exceeds current indication. © 2016 BioFactors, 43(3):388-399, 2017.

The effect of chemically modified alginates on macrophage phenotype and biomolecule transport.

Macrophage (MΦ) reprogramming has received significant attention in applications such as cancer therapeutics and tissue engineering where the host immune response to biomaterials is crucial in determining the success or failure of an implanted device. Polymeric systems can potentially be used to redirect infiltrating M1 MΦs toward a proangiogenic phenotype. This work exploits the concept of MΦ reprogramming in the engineering of materials for improving the longevity of tissue engineering scaffolds. We have investigated the effect of 13 different chemical modifications of alginate on MΦ phenotype. Markers of the M1 response-tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthase-and the M2 response-arginase-were measured and used to determine the ability of the materials to alter MΦ phenotype. It was found that some modifications were able to reduce the pro-inflammatory response of M1 MΦs, others appeared to amplify the M2 phenotype, and the results for two materials suggested they were able to reprogram a MΦ population from M1 to M2. These findings were supplemented by studies done to examine the permselectivity of the materials. Diffusion of TNF-α was completely prevented through some of these materials, while up to 84% was found to diffuse through others. The diffusion of insulin through the materials was statistically consistent. These results suggest that the modification of these materials might alter mass transport in beneficial ways. The ability to control polarization of MΦ phenotypes with immunoprotective materials has the potential to augment the success of tissue engineering scaffolds. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1707-1719, 2016.

Enhanced resolution of experimental ARDS through IL-4-mediated lung macrophage reprogramming.

Despite intense investigation, acute respiratory distress syndrome (ARDS) remains an enormous clinical problem for which no specific therapies currently exist. In this study, we used intratracheal lipopolysaccharide or Pseudomonas bacteria administration to model experimental acute lung injury (ALI) and to further understand mediators of the resolution phase of ARDS. Recent work demonstrates macrophages transition from a predominant proinflammatory M1 phenotype during acute inflammation to an anti-inflammatory M2 phenotype with ALI resolution. We tested the hypothesis that IL-4, a potent inducer of M2-specific protein expression, would accelerate ALI resolution and lung repair through reprogramming of endogenous inflammatory macrophages. In fact, IL-4 treatment was found to offer dramatic benefits following delayed administration to mice subjected to experimental ALI, including increased survival, accelerated resolution of lung injury, and improved lung function. Expression of the M2 proteins Arg1, FIZZ1, and Ym1 was increased in lung tissues following IL-4 treatment, and among macrophages, FIZZ1 was most prominently upregulated in the interstitial subpopulation. A similar trend was observed for the expression of macrophage mannose receptor (MMR) and Dectin-1 on the surface of alveolar macrophages following IL-4 administration. Macrophage depletion or STAT6 deficiency abrogated the therapeutic effect of IL-4. Collectively, these data demonstrate that IL-4-mediated therapeutic macrophage reprogramming can accelerate resolution and lung repair despite delayed use following experimental ALI. IL-4 or other therapies that target late-phase, proresolution pathways may hold promise for the treatment of human ARDS.