Tumor Necrosis Factor-alpha Production Research Articles

CBX4 promotes antitumor immunity by suppressing Pdcd1 expression in T cells.

E3 SUMO-protein ligase CBX4 (CBX4), a key component of polycomb-repressive complexes 1 (PRC1), has been reported to regulate a variety of genes implicated in tumor growth, metastasis, and angiogenesis. However, its role in T-cell-mediated antitumor immunity remains elusive. To shed light on this issue, we generated mice with T-cell-specific deletion of Cbx4. Tumor growth was increased in the knockout mice. Additionally, their tumor-infiltrating lymphocytes exhibited impaired tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) production, with an elevated programmed cell death protein 1 (PD-1) level. In fact, dysregulated Pdcd1 expression was observed in all major subsets of peripheral T cells from the knockout mice, which was accompanied by a functional defect in response to T-cell receptor (TCR) stimulation. In support of a direct link between CBX4 and PD-1, Cbx4 overexpression resulted in the downregulation of Pdcd1 expression. Epigenetic analyses indicated that Cbx4 deficiency leads to diminished accumulation of inhibitory histone modifications at conserved region (CR)-C and CR-B sites of the Pdcd1 promoter, namely mono-ubiquitinated histone H2A at lysine 119 (H2AK119ub1) and trimethylated histone H3 at lysine 27 (H3K27me3). Moreover, inhibition of either the E3 ligase activity of polycomb-repressive complexes 1 (PRC1) or the methyltransferase activity of polycomb-repressive complexes 2 (PRC2) restores Pdcd1 expression in Cbx4-transfected cells. Cumulatively, this study reveals a novel function of CBX4 in the regulation of T-cell function and expands our understanding of the epigenetic control of Pdcd1 expression.

Lithospermum erythrorhizon Siebold & Zucc. extract reduces the severity of endotoxin-induced uveitis

BackgroundUveitis is an inflammatory eye condition that threatens vision, and effective anti-inflammatory treatments with minimal side effects are necessary to treat uveitis. PurposeThis study aimed to investigate the effects of Lithospermum erythrorhizon Siebold & Zucc. against endotoxin-induced uveitis in rat and mouse models. MethodsEndotoxin-induced uveitis models of rats and mice were used to evaluate the effects of l. erythrorhizon treatment. Clinical inflammation scores and retinal thickness were assessed in the extract of l. erythrorhizon-treated rats. Histopathological examination revealed inflammatory cell infiltration into the ciliary body. Protein concentration, cellular infiltration, and prostaglandin-E2 levels were measured in the aqueous humor of the extract of l. erythrorhizon-treated rats. Protective effects of l. erythrorhizon on the anterior segment of the eye were examined in mice with endotoxin-induced uveitis. Additionally, we investigated the effect of l. erythrorhizon on the expression of pro-inflammatory cytokines [tumor necrosis factor alpha, interleukin-6, and interleukin-8] in lipopolysaccharide-stimulated THP1 human macrophages and examined the involvement of nuclear factor kappaB/activator protein 1 and interferon regulatory factor signaling pathways. Furthermore, three components of l. erythrorhizon were identified and assessed for their inhibitory effects on LPS-induced inflammation in RAW264.7 macrophage cells. ResultsTreatment of the extract of l. erythrorhizon significantly reduced clinical inflammation scores and retinal thickening in rats with endotoxin-induced uveitis. Histopathological examination revealed decreased inflammatory cell infiltration into the ciliary body. The extract of l. erythrorhizon effectively reduced the protein concentration, cellular infiltration, and PG-E2 levels in the aqueous humor of rats with endotoxin-induced uveitis. In mice with endotoxin-induced uveitis, the extract of l. erythrorhizon demonstrated a protective effect on the anterior segment of the eye by reducing inflammation and retinal thickening. The extract of l. erythrorhizon suppressed the expression of pro-inflammatory cytokines (tumor necrosis factor alpha, interleukin-6, and interleukin-8) in lipopolysaccharide-induced inflammation in THP1 human macrophages, by modulating nuclear factor kappaB/activator protein 1 and interferon regulatory factor signaling pathways. Moreover, shikonin, acetylshikonin, and β, β-dimethylacryloylshikonin showed dose-dependent inhibition of nitric oxide, tumor necrosis factor alpha and interleukin-6 production in RAW264.7 macrophage cells. ConclusionThe extract of l. erythrorhizon is a potential therapeutic agent for uveitis management. Administration of the extract of l. erythrorhizon led to reduced inflammation, retinal thickening, and inflammatory cell infiltration in rat and mouse models of uveitis. The compounds (shikonin, acetylshikonin, and β, β-dimethylacryloylshikonin) identified in this study played crucial roles in mediating the anti-inflammatory effects of l. erythrorhizon. These findings indicate that the extract of l. erythrorhizon and its constituent compounds are promising candidates for further research and development of novel treatment modalities for uveitis.

In silico analysis of missense SNPs in TNFR1a and their possible therapeutic or pathogenic role in immune diseases

Tumor necrosis factor alpha (TNFa) is an inflammatory cytokine that is involved in the pathogenesis of various inflammatory disorders including rheumatoid arthritis. TNF-alpha receptor I (TNFR1a) is one of the receptors TNFa binds with for its activation. Any variation in this receptor might affect the role of TNFa in successive events. Amino acid residue substitutions might happen in TNFR1a through non-synonymous single nucleotide polymorphisms (nsSNPs) which may alter the functioning of TNFa, hence, identifying any such substitutions is of paramount significance. In this study, six nsSNPs at five different evolutionary conserved regions are predicted to be detrimental to the structure and/or function of TNFR1a by using numerous computational tools. Their 3D models are also proposed in this study. Besides, they were found to reduce the stability and affect the molecular mechanisms of this protein. Two contrasting possibilities might happen because of these substitutions. One, they might reduce the production of TNFa which is overexpressed in inflammatory diseases, hence can play therapeutic role in such diseases. Second, they might possibly hinder the apoptosis to occur which can effectuate the uncontrolled division of cells, hence can be pathogenic in diseases like cancer. Further investigations on these nsSNPs using animal models and at cellular level will open doors to understand the underlying mechanisms behind various diseases.

Modulation of oxidized low-density lipoprotein-affected macrophage efferocytosis by mitochondrial calcium uniporter in a murine model

ObjectiveEfferocytosis dysfunction contributes to the progression and rupture of atherosclerotic plaques. Efferocytosis is crucially modulated by intracytoplasmic Ca2+, and mitochondrial calcium uniporter (MCU) complex proteins serve as key channels for regulating Ca2+ concentration. Therefore, it was speculated that MCU may affect the development of atherosclerosis (AS) by regulating efferocytosis. In the present study, we aimed to investigate whether MCU could affect foam cell formation by regulating efferocytosis. MethodsWe stimulated primary macrophages (Møs) using oxidized low-density lipoprotein (ox-LDL) to mimic the atherosclerotic microenvironment and treated them with Ru360, an MCU-specific inhibitor, and UNC1062, an inhibitor of efferocytosis. Additionally, we conducted double staining to determine the Mø efferocytosis rate. We measured the expression of MCU complexes and efferocytosis-associated proteins using western blotting (WB) and real-time quantitative polymerase chain reaction (RT-qPCR), respectively. In addition, we separately detected the Ca2+ level in the cytoplasm and mitochondria (MT) using Fluo-4 AM and Rhod-2 methods. We separately determined the reactive oxygen species (ROS) level in cytoplasm and MT using dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescent probing method and Mito-SOXTM superoxide indicator staining. Additionally, we conducted the enzyme-linked immunosorbent assay (ELISA) to detect the production of interleukin-6 (IL-6), interleukin-18 (IL-18), interleukin-1β (IL-1β), and tumor necrosis factor-alpha (TNF-α). Oil Red O staining was performed to measure cytoplasmic lipid levels. ResultsRu360 attenuated ox-LDL-induced efferocytosis dysfunction, and attenuated the upregulation of MCU and MCUR1 induced by ox-LDL, and meanwhile attenuated the downregulation of MCUb induced by ox-LDL. Ru360 attenuated the decrease of intracytoplasmic Ca2+ concentration induced by ox- LDL, Ru360 also attenuated the ROS production induced by ox- LDL, attenuated the release of IL-6, IL-18, IL-1β, and TNF-α induced by ox- LDL, and attenuated the increase of intracytoplasmic lipid content induced by ox-LDL. UNC1062 attenuated the effects of Ru360 in reducing inflammatory cytokines and intracytoplasmic lipid content. ConclusionsIn this study, we found that MCU inhibition modulated intracytoplasmic Ca2+ concentration, improved impaired Mø efferocytosis, and reduced ROS generation. Macrophage efferocytosis removed apoptotic cells and prevented the release of inflammatory factor and foam cell formation, and this can be a potential new therapeutic target for alleviating atherosclerosis.

Exploring in vitro and in vivo anti-inflammatory activities of the Thai traditional remedy Kheaw-Hom and its bioactive compound, ethyl p-methoxycinnamate, and ethnopharmacological analysis

Ethnopharmacological relevanceKheaw-Hom (KH) remedy, a Thai traditional medicine (TTM) on the National List of Essential Medicines, has long been clinically used to treat fever and inflammation in children. However, no in vitro or in vivo anti-inflammatory or bioactive compound studies are published in the literature. Aims of the studyTo explore the in vitro and in vivo anti-inflammatory activities of KH remedy and its bioactive compound and analyze relationships between flavor and ethnopharmacological activities of plant components in KH remedy according to TTM theory. Materials and methodsEthyl p-methoxycinnamate (EPMC), a bioactive compound of KH remedy was analyzed using high performance liquid chromatography (HPLC). In vitro anti-inflammatory activities of ethanolic extract (KHE), aqueous extract (KHA), acid-hydrolysis of KHA (KHA-h), acid-hydrolysis of KH powder (KHP-h), and EPMC were investigated using lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E2 (PGE2), and tumor necrosis factor-alpha (TNF-α) production in murine macrophage RAW 264.7 cells. In vivo anti-inflammatory activities of KH powder (KHP) and KHE were determined using carrageenan-induced paw edema and ethyl phenylpropiolate (EPP)-induced ear edema in rats and PGE2 production in tissue samples was examined. ResultsKHP-h showed the highest EPMC content (21.33 ± 1.08 mg/g of extract) and inhibited PGE2, NO, and TNF-α production with IC50 values of 11.92 ± 0.21, 30.61 ± 3.12, and 56.71 ± 2.91 μg/mL, respectively, followed by KHE and KHA-h while KHA did not. EPMC, a bioactive compound of KH remedy showed high anti-inflammatory activities through three pathways. KHP oral administration (100 mg/kg) significantly minimized rat paw inflammation at 1, 2, and 3 h while KHE (100 mg/kg) noticeably reduced at 2 and 3 h. KHP (100, 200, and 400 mg/kg) and KHE (100 mg/kg) significantly inhibited PGE2 production. KHP (1% w/v) notably reduced rat ear edema at 30, 60, and 120 min whereas KHE at all concentrations decreased swelling at 120 min. KHP and KHE at all doses significantly inhibited PGE2 production. Cool flavor was the main KH remedy flavor. Spicy plant components and some fragrant components showed high anti-inflammatory activity. ConclusionsResults from the in vivo study strongly paralleled the in vitro study. These findings support the rational use of KH remedy according to TTM theory for fever treatment and inflammation in children.

FattyAcid-Binding Protein 4 is Essential for the Inflammatory and Metabolic Response of Microglia to Lipopolysaccharide.

Prolonged activation of microglia leads to excessive release of proinflammatory mediators, which are detrimental to brain health. Therefore, there are significant efforts to identify pathways mediating microglial activation. Recent studies have demonstrated that fatty acid-binding protein 4 (FABP4), a lipid binding protein, is a critical player in macrophage-mediated inflammation. Given that we have previously identified FABP4 in microglia, the aim of this study was to assess whether FABP4 activity contributed to inflammation, metabolism and immune function (i.e. immunometabolism) in immortalised mouse microglia (BV-2 cells) using the proinflammatory stimulus lipopolysaccharide (LPS) to induce general microglial activation. Microglial FABP4 expression was significantly increased following exposure to LPS, an outcome associated with a significant increase in microglial proliferation rate. LPS-stimulated BV-2 microglia demonstrated a significant increase in the production of reactive oxygen species (ROS) and tumour necrosis factor-alpha (TNF-α), phosphorylation of c-Jun N-terminal kinase (JNK), increased expression of Toll-like receptor 4 (TLR4), and reduced expression of uncoupling protein 2 (UCP2), all of which were reversed following FABP4 genetic silencing and chemical inhibition with BMS309403. The oxidation rate of 3H-oleic acid and microglial uptake of 3H-2-deoxy-D-glucose were modulated with LPS activation, processes which were restored with genetic and chemical inhibition of FABP4. This is the first study to report on the critical role of FABP4 in mediating the deleterious effects of LPS on microglial immunometabolism, suggesting that FABP4 may present as a novel therapeutic target to alleviate microglia-mediated neuroinflammation, a commonly reported factor in multiple neurodegenerative diseases.

Deficiency of hydrogen sulfide production and pregnancy rate in an experimental model: Association with preterm delivery.

Pro-inflammatory phenomena drive preterm delivery (PTD). Hydrogen sulfide is a gasotransmitter with anti-inflammatory properties produced through the activity of the enzyme cystathionine-γ-lyase (CSE), and its impact was studied in models of normal delivery and PTD in mice. Female CSE+/+ and CSE-/- mice were mated with male CSE+/+ mice; mating was done with drinking water unsupplemented and supplemented with cysteine. The pregnancy rate was monitored. PTD was induced by the intraperitoneal injection of bacterial lipopolysaccharide (LPS) on day 14.5 of pregnancy. Mice were sacrificed for tissue collection and splenocyte isolation after 6 and 12h. Isolated splenocytes were stimulated for the production of tumor necrosis factor-alpha (TNFα), interleukin (IL)-10 and interferon-gamma (IFNγ); TNFα and vascular endothelial growth factor (VEGF) were measured in the fetuses and the placenta. The successful pregnancy rate was lower in CSE-/- mice and it was restored with cysteine supplementation. CSE deficiency was associated with higher tissue concentrations of TNFα in the fetuses, attenuated IL-10 responses and higher IFNγ production from splenocytes. CSE deficiency was not associated with PTD. Following PTD induction, CSE-/- mice did not show attenuated IL-10 responses but the production of TNFα and IFNγ was lowered over-time; placental VEGF was also increased over-time. CSE deficiency has an unfavorable impact on pregnancy. H2 S deficiency through CSE does not drive PTD but mediates pro-inflammatory phenomena in fetuses.

Soybean (Glycine max) INFOGEST Colonic Digests Attenuated Inflammatory Responses Based on Protein Profiles of Different Varieties.

Soybean compounds have been established to modulate inflammation, but less is known about how whole soybean compositions work together after digestion. The objective was to evaluate and compare the anti-inflammatory responses of different soybean varieties under simulated gastrointestinal digestion, with additional consideration of the glycinin:β-conglycinin ratio (GBR). Soybean colonic digests (SCD) inhibited cyclooxygenase (COX)-2 (25-82%), 5-lipoxidase (LOX) (18-35%), and inducible nitric oxide (iNOS) (8-61%). Varieties 88, GN3, and 93 were the most effective inhibitors. SCD (1 mg/mL) of varieties 81 and GN1 significantly (p < 0.05) reduced nitrite production by 44 and 47%, respectively, compared to lipopolysaccharide (LPS)-stimulated macrophages. SCD effectively reduced pro-inflammatory cytokine interleukin (IL)-6 (50 and 80% for 96 and GN1, respectively). Western blot results showed a decrease in the expression of iNOS, p65, and p50. The GBR was in the range of 0.05-1.57. Higher ratio correlated with higher production of IL-1β (r = 0.44) and tumor necrosis factor-alpha (TNF-α, r = 0.56). Inflammatory microarray results showed a significant decrease in expression of markers granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-6 in cells treated with GN1 SCD compared to LPS. The results suggested that SCD exerted its anti-inflammatory potential through nuclear factor kappa B (NF-κΒ) pathway inhibition by decreasing the levels of NF-κB-dependent cytokines and subunits, and inhibition of pro-inflammatory enzyme activity.

ANGPTL3 affects the metastatic potential and the susceptibility of ovarian cancer cells to natural killer cell-mediated cytotoxicity

High metastatic potential and resistance to immunotherapy lead to poor survival in patients with ovarian cancer. Angiopoietin-like protein 3 is aberrantly expressed and exerts diverse roles in the progression of several cancers. However, its function in ovarian cancer is unknown. Here, decreased expression of angiopoietin-like protein 3 was observed in ovarian cancer tissues and cells. Moreover, patients with high expression of angiopoietin-like protein 3 had longer overall survival and progression-free survival, indicating a good prognosis for patients. Furthermore, angiopoietin-like protein 3 overexpression inhibited ovarian cancer cell proliferation. Concomitantly, high invasion and the occurrence of epithelial-to-mesenchymal transition of cancer cells were restrained after angiopoietin-like protein 3 elevation. Up-regulation of angiopoietin-like protein 3 expression further increased interleukin 2-treated natural killer cell activation by increasing CD69 expression and production of interferon gamma and tumor necrosis factor-alpha when natural killer cells were co-cultured with ovarian cancer cells. Importantly, angiopoietin-like protein 3 overexpression enhanced natural killer cell-evoked cytotoxicity and apoptosis of cancer cells, indicating the pro-tumor killing ability of angiopoietin-like protein 3 for natural killer cells. Mechanistically, angiopoietin-like protein 3 elevation inhibited activation of the Janus Kinase/Signal transducer and activator of transcription 3 signaling in ovarian cancer cells by inhibiting protein expression of phospho-Janus Kinase 2, phospho-Signal transducer and activator of transcription 3, downstream matrix metallopeptidase 2 and programmed cell death 1. Moreover, blocking the Janus Kinase/Signal transducer and activator of transcription 3 pathway via their inhibitor Stattic restrained ovarian cancer cell proliferation, invasion, epithelial-to-mesenchymal transition, and promoted natural killer cell killing to ovarian cancer cells. Thus, these findings reveal that angiopoietin-like protein 3 may act as an anti-oncogenic regulator to inhibit the metastatic potential and enhance the susceptibility of ovarian cancer cells to natural killer cell-mediated killing. Consequently, angiopoietin-like protein 3 may regulate metastatic potential and immune escape from natural killer cells, indicating a promising therapeutic strategy for ovarian cancer.

Expression of toll-like receptor 4 and its associated cytokines from peripheral blood mononuclear cells in Leghorn chickens.

Immune cells require toll-like receptor 4 (TLR4) to respond to lipopolysaccharides (LPS) by releasing pro-inflammatory cytokines. Peripheral blood mononuclear cells (PBMCs) are used to assess changes in cytokines released in response to diseases or pathogens. This study aimed to assess TLR4 gene expression in PBMCs from Leghorn chicken and the release of related cytokines. Peripheral blood mononuclear cells were isolated from blood samples obtained from Leghorn chicks. The PBMC cultures were stimulated with various concentrations of LPS (0.01-1 μg/ml). Polymerase chain reaction was used to detect TLR4 expression. The production of tumor necrosis factor-alpha (TNF-α) and interleukins (IL-1β and IL-6) was quantified using an enzyme-linked immunosorbent assay. We found that TLR4 was expressed in both non-stimulated and stimulated Leghorn chicken PBMCs. In addition, the release of TNF-α, IL-1β, and IL-6 levels in Leghorn chicken PBMCs increased significantly with an increase in LPS concentration (0.01-1 μg/mL) (p < 0.05). Although TLR4 was expressed in both non-stimulated and stimulated Leghorn chicken PBMCs, its expression was significantly higher in LPS-stimulated PBMCs Therefore, the chicken's endotoxin response can be assessed by evaluating the pro-inflammatory cytokine production from PBMCs.

Human mesenchymal stem-derived extracellular vesicles improve body growth and motor function following severe spinal cord injury in rat.

Spinal cord injury (SCI) in young adults leads to severe sensorimotor disabilities as well as slowing of growth. Systemic pro-inflammatory cytokines are associated with growth failure and muscle wasting. Here we investigated whether intravenous (IV) delivery of small extracellular vesicles (sEVs) derived from human mesenchymal stem/stromal cells (MSC) has therapeutic effects on body growth and motor recovery and can modulate inflammatory cytokines following severe SCI in young adult rats. Contusional SCI rats were randomized into three different treatment groups (human and rat MSC-sEVs and a PBS group) on day 7 post-SCI. Functional motor recovery and body growth were assessed weekly until day 70 post-SCI. Trafficking of sEVs after IV infusions in vivo, the uptake of sEVs in vitro, macrophage phenotype at the lesion and cytokine levels at the lesion, liver and systemic circulation were also evaluated. An IV delivery of both human and rat MSC-sEVs improved functional motor recovery after SCI and restored normal body growth in young adult SCI rats, indicating a broad therapeutic benefit of MSC-sEVs and a lack of species specificity for these effects. Human MSC-sEVs were selectively taken up by M2 macrophages in vivo and in vitro, consistent with our previous observations of rat MSC-sEV uptake. Furthermore, the infusion of human or rat MSC-sEVs resulted in an increase in the proportion of M2 macrophages and a decrease in the production of the pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-6 at the injury site, as well as a reduction in systemic serum levels of TNF-α and IL-6 and an increase in growth hormone receptors and IGF-1 levels in the liver. Both human and rat MSC-sEVs promote the recovery of body growth and motor function after SCI in young adult rats possibly via the cytokine modulation of growth-related hormonal pathways. Thus, MSC-sEVs affect both metabolic and neurological deficits in SCI.

Stress granule activation attenuates lipopolysaccharide-induced cardiomyocyte dysfunction

BackgroundSepsis is the leading cause of death in intensive care units. Sepsis-induced myocardial dysfunction, one of the most serious complications of sepsis, is associated with higher mortality rates. As the pathogenesis of sepsis-induced cardiomyopathy has not been fully elucidated, there is no specific therapeutic approach. Stress granules (SG) are cytoplasmic membrane-less compartments that form in response to cellular stress and play important roles in various cell signaling pathways. The role of SG in sepsis-induced myocardial dysfunction has not been determined. Therefore, this study aimed to determine the effects of SG activation in septic cardiomyocytes (CMs).MethodsNeonatal CMs were treated with lipopolysaccharide (LPS). SG activation was visualized by immunofluorescence staining to detect the co-localization of GTPase-activating protein SH3 domain binding protein 1 (G3BP1) and T cell-restricted intracellular antigen 1 (TIA-1). Eukaryotic translation initiation factor alpha (eIF2α) phosphorylation, an indicator of SG formation, was assessed by western blotting. Tumor necrosis factor alpha (TNF-α) production was assessed by PCR and enzyme-linked immunosorbent assays. CMs function was evaluated by intracellular cyclic adenosine monophosphate (cAMP) levels in response to dobutamine. Pharmacological inhibition (ISRIB), a G3BP1 CRISPR activation plasmid, and a G3BP1 KO plasmid were employed to modulate SG activation. The fluorescence intensity of JC-1 was used to evaluate mitochondrial membrane potential.ResultsLPS challenge in CMs induced SG activation and resulted in eIF2α phosphorylation, increased TNF-α production, and decreased intracellular cAMP in response to dobutamine. The pharmacological inhibition of SG (ISRIB) increased TNF-α expression and decreased intracellular cAMP levels in CMs treated with LPS. The overexpression of G3BP1 increased SG activation, attenuated the LPS-induced increase in TNF-α expression, and improved CMs contractility (as evidenced by increased intracellular cAMP). Furthermore, SG prevented LPS-induced mitochondrial membrane potential dissipation in CMs.ConclusionSG formation plays a protective role in CMs function in sepsis and is a candidate therapeutic target.

Aspergillus fumigatus Extracellular Vesicles Display Increased Galleria mellonella Survival but Partial Pro-Inflammatory Response by Macrophages

Fungal extracellular vesicles (EVs) mediate intra- and interspecies communication and are critical in host-fungus interaction, modulating inflammation and immune responses. In this study, we evaluated the in vitro pro- and anti-inflammatory properties of Aspergillus fumigatus EVs over innate leukocytes. A. fumigatus EVs induced a partial proinflammatory response by macrophages, characterized by increased tumor necrosis factor-alpha production, and increased gene expression of induced nitric oxide synthase and adhesion molecules. EVs induce neither NETosis in human neutrophils nor cytokine secretion by peripheral mononuclear cells. However, prior inoculation of A. fumigatus EVs in Galleria mellonella larvae resulted in increased survival after the fungal challenge. Taken together, these findings show that A. fumigatus EVs play a role in protection against fungal infection, although they induce a partial pro-inflammatory response.

Hypoxia-inducible factor prolyl hydroxylase inhibitors suppressed thymic stromal lymphopoietin production and allergic responses in a mouse air-pouch-type ovalbumin sensitization model.

Atopic dermatitis (AD) is an allergic skin disease, triggered by excessive type 2 immune reactions. Thymic stromal lymphopoietin (TSLP) is an epithelial-derived cytokine that induces type 2 immune response through dendritic cell activation. Therefore, TSLP inhibitors may serve as novel antiallergic drugs. Hypoxia-inducible factor (HIF) activation in the epithelia contributes to several homeostatic phenomena, such as re-epithelialization. However, the effects of HIF activation on TSLP production and immune activation in the skin remain unclear. In this study, we found that selective HIF prolyl hydroxylase inhibitors (PHD inhibitors), which induce HIF activation, suppressed TSLP production in a mouse ovalbumin (OVA) sensitization model. PHD inhibitors also suppressed the production of tumor necrosis factor-alpha (TNF-α), which is a major inducer of TSLP production, in this mouse model and in a macrophage cell line. Consistent with these findings, PHD inhibitors suppressed OVA-specific IgE levels in the serum and OVA-induced allergic responses. Furthermore, we found a direct suppressive effect on TSLP expression in a human keratinocyte cell line mediated by HIF activation. Taken together, our findings suggest that PHD inhibitors exert antiallergic effects by suppressing TSLP production. Controlling the HIF activation system has therapeutic potential in AD.

TNF inhibits AQP2 expression via a miR137-dependent pathway

We previously showed that production of tumor necrosis factor-alpha (TNF) by the kidney, under normotensive, non-inflammatory conditions, inhibits expression of angiotensinogen in the proximal tubule and NKCC2 isoform A in the thick ascending limb of Henle’s loop via micro-RNA (miRNA)-dependent mechanisms. As miR-137 is a regulator of aquaporin-2 (AQP2) expression and TNF inhibits the expression of several extrarenal aquaporins, we tested the hypothesis that TNF inhibits AQP2 in the kidney via a miR-137-dependent mechanism. Target seed regions of mmu-miR-137 are conserved in the 3'-untranslated region (3’-UTR) of mouse AQP2 mRNA and luciferase assays showed that mmu-miR-137 directly targeted the 3’-UTR of mouse AQP2. Moreover, AQP2 expression was decreased by approximately 70% (P&lt;0.05) in primary renal inner medullary collecting duct (IMCD) cells transfected with a miRNA mimic of mmu-miR-137, indicating that miR-137 directly targets AQP2 mRNA in these cells. The decrease in AQP2 mRNA accumulation was accompanied by a 53% decrease (P&lt;0.05) in AQP2 protein expression when mmu-miR-137 was overexpressed in IMCD cells. Exposure of IMCD cells for 2 hr to 400 mosmol/kg H2O medium, made by increasing the osmolality by adding NaCl, increased mmu-miR-137 mRNA expression about 2-fold (P&lt;0.05) as determined by quantitative RT-PCR analysis. These conditions also increased TNF production approximately 2-fold (P&lt;0.05). To determine if the increase in mmu-miR-137 mRNA expression was related to the concomitant increase in TNF, cells were transfected with either a lentivirus construct to silence TNF or a control construct. The silencing construct, EGFP-shTNF-ex4, but not U6 control, decreased mmu-miR-137 mRNA expression in the IMCD cells exposed to 400 mosmol/kg H2O medium by approximately 63% (P&lt;0.05) indicating that TNF upregulates mmu-miR-137 mRNA expression in IMCD cells. The levels of miR-137 also increased approximately 2-fold (P&lt;0.05) in inner medulla isolated from age- and sex-matched male or female mice given 1% NaCl in the drinking water (HS) for 3 days. Six days after intrarenal injection of lentivirus EGFP-shTNF-ex4 to silence TNF, renal AQP2 mRNA levels increased approximately 3-fold (P&lt;0.05) in inner medullary tissue isolated from male or female mice given HS compared with their respective control groups. In addition, renal silencing of TNF in male or female mice given HS exhibited an increase in AQP2 protein expression the inner medulla compared with control group as determined by Western blot analysis. Similarly, EGFP-shTNF-ex4, but not U6, decreased miR-137 levels in the inner medulla in male or female mice given HS. Taken together, these data reveal a novel mechanism by which TNF mediates the inhibition of AQP2 via miR-137, indicating that miR-137 may be important for studying TNF-regulated effects involving the AQP2 pathway on renal water excretion and blood pressure regulation. NIH grants R01 HL133077 and HL153525 This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

T cell pro-inflammatory cytokine production in young adults with major depressive disorder

Background: Major Depressive Disorder (MDD) is increasingly prevalent in young adults and is a significant contributor to disease burden worldwide. Previously we have shown that young adults with MDD produce greater T cell mitochondrial ROS compared to their heathy non-depressed counterparts. Because evidence from rodent models of stress-related mood disorders demonstrates that increased T cell mitoROS drives excessive proinflammatory cytokine production, we next sought to determine if either CD4+ (Helper) or CD8+ (cytotoxic) T cells likewise produce increased proinflammatory cytokines in young adults with MDD. We hypothesized that there will be elevated proinflammatory cytokine production in young adults with MDD compared to their healthy non-depressed counterparts. Methods: Peripheral blood mononuclear cells were isolated by density centrifugation from 5 young adults with MDD having mild to moderate symptom severity and 9 non-depressed young healthy adults. Interleukin 2 (IL-2), Interleukin 6 (IL-6), Interferon Gamma (IFN-γ), and Tumor Necrosis Factor alpha (TNF-) production were assessed by flow cytometry. All data are expressed as mean SE and group differences were assessed by unpaired T test. Results: We found that adults with MDD exhibited a greater proportion of CD8+ Interleukin 6 (IL-6) (n= 8; 5 HA, 3 MDD) (HA = 22 3.5%, MDD = 255.6%; P= 0.004) producing cells compared to healthy. There were no significant differences in the proportions of CD8+ cells producing IFN-γ (HA = 14 1.2%, MDD = 3.1%; P= 0.31), IL-2 (HA =76 3.9%, MDD = 69 6.6%; P= 0.17), and TNF- (HA = 21 2.3%, MDD = 23.5%; P= 0.11) in those with MDD compared to controls. Additionally, there were no differences in CD4+ production of these same cytokines. We also assessed phenotype of the T cells using CD27 (central vs effector) and CD45 RA (Naïve vs TEMRA). Interestingly, a greater proportion of TNF- producing CD8+ and CD4+ cells exhibited an effector memory phenotype in adults with MDD compared to controls (CD8: HA = 25.8 2.4%, MDD = 46.8 3.3%; P= 0.0001; CD4+: HA=31 2.9%, MDD = 394.3%; P= 0.05). These data provide insight into the T cell subtypes that may be driving the inflammation associated with MDD. Conclusion: These preliminary findings suggest that young adults with MDD may exhibit a proinflammatory T cell phenotype characterized by greater IL-6 and TNF- production. NIH R21 MH123928 and R00133414 (JLG), NIH K01AG061271 and R01AG060395 (DWT). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Highly oxygenated germacrane-type sesquiterpenoids from the whole plant of Salvia cavaleriei H.Lév. and their biological activities

The entire plant Salvia cavaleriei H.Lév. (Lamiaceae) is used as a traditional Chinese herbal medicine. Its leaves are edible, and the flowers can be soaked in water to make a health-care tea. In an effort to find natural bioactive chemical components, twelve undescribed germacrane-type sesquiterpenoids, salcavalins A-L, were isolated from the whole plant of S. cavaleriei and were identified as analogs. This is the first study to isolate highly oxygenated germacrane-type sesquiterpenoids from this plant. The structures of these undescribed compounds were elucidated by various spectroscopic methods, and their absolute configurations were confirmed by single-crystal X-ray diffraction analysis with Cu Kα radiation and electronic circular dichroism calculations. The biological activity of these undescribed compounds on the production of tumor necrosis factor-alpha in lipopolysaccharide induced NR8383 cells was evaluated, and salcavalins I and K showed anti-inflammatory activity to some extent. Salcavalins A-C, F and L were found to be neuroprotective with antiparkinsonic potential in a nematode (Caenorhabditis elegans) model. In addition, salcavalins F and I displayed marked phytotoxic activity against radish seeds at a low concentration of 50 ppm. Our findings provide scientific justification to show that bioactive sesquiterpenoids from the edible herb have anti-inflammatory in vitro, neuroprotective and phytotoxic activities.

Design and synthesis of a novel class of PDE4 inhibitors with antioxidant properties as bifunctional agents for the potential treatment of COPD

It is well known that chronic obstructive pulmonary disease (COPD) patients are always trapped in the vicious circle of inflammation and oxidative stress, therefore anti-inflammatory and antioxidant bifunctional agents may interrupt this vicious cycle in COPD. Phosphodiesterase 4 (PDE4) inhibitors, as anti-inflammatory drugs, have been used for COPD treatment in clinical, and the PDE4 inhibitors with antioxidant properties may be a good strategy to design bifunctional agents for COPD. Sappanone A was the first PDE4 inhibitor with antioxidant properties we identified from natural products in our previous study, which was used by us as a hit compound to design new bifunctional agents for COPD in this study. 27 derivatives of sappanone A including homoisoflavonoids, aurones and chalcones were designed and synthesized by innovatively fusing the antioxidant pharmacophore of catechol from polyphenols and the pharmacophore of catechol ether abstracted from the PDE4 inhibitors of the catechol ether class such as rolipram, roflumilast and apremilast respectively. All the compounds were assayed for the PDE4 inhibitory and radical scavenging against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) activities in vitro. Herein we obtained a series of bifunctional compounds with better PDE4 inhibitory activity than sappanone A, and their free radical scavenging activities were superior to edaravone in vitro. In addition, they can reduce tumour necrosis factor-alpha (TNF-α) production induced by lipopolysaccharide (LPS) in RAW264.7 macrophages and malondialdehyde (MDA) production induced by Fe2+ in mouse lung homogenate. Meanwhile, it showed outstanding abilities in reducing Fe3+ and complexing Fe2+. 6o, as the candidate anti-inflammatory and antioxidant bifunctional compound, exhibited good drug-likeness, ADME (Absorption, Distribution, Metabolism, Excretion) properties and human liver microsomal stability. In vivo, 6o (50 mg/kg and 100 mg/kg, i. p.) distinctly prevented LPS-induced serum levels of TNF-α in mice. In conclusion, the preliminary investigation provided a novel class of PDE4 inhibitors with antioxidant properties as bifunctional agents for the potential treatment of COPD, which can interrupt the vicious cycle of chronic inflammation and oxidative stress in COPD.

The role of regulatory micro-RNAs in inflammatory processes and production of tumor necrosis factor-alpha in patients with rheumatoid arthritis

Background. Micro-RNAs are fundamental agents of post-transcriptional control of gene expression. In recent years many works have appeared on the possible role of micro-RNAs in rheumatoid arthritis (RA). Studies of the role of micro-RNA and the relationship with the synthesis of tumor necrosis factor-α (TNF-α) are very promising for understanding the pathogenesis and treatment of RA and other autoimmune diseases. The purpose of the research was to study the role of regulatory micro-RNAs in inflammatory processes and the possible connection with the production of TNF-α in patients with RA. Materials and methods. 29 patients with active RA and 20 healthy individuals (control) were examined. All subjects were examined for 16 micro-RNAs. The choice of micro-RNA was based on previous studies and theoretical conclusions (according to the miRWalk database). Rheumatoid factor, the level of antibodies to cyclic peptides containing citrulline, C-reactive protein (СRP), levels of TNF-α (serum, spontaneous, and stimulated) were determined in the blood of patients. Results. Statistical analysis demonstrated significant overexpression of miR-221, miR-203, miR-146b, miR-132, miR-21 and miR-17-3p and inhibition of miR-223 synthesis in RA patients. The activation of TNF-α synthesis at rest and the increased production of TNF-α by mononuclear cells after stimulation in RA were shown. Differences in the levels of relative expression of some micro-RNAs between seropositive and seronegative groups of RA patients were found, but only hyperexpression of miR-155 was highly reliable. For the first time, a possible relationship between TNF-α production and miR-29 and miR-155 micro-RNAs, as well as a correlation between miR-16, miR-99b and miR-203 and CRP levels, was revealed. Conclusions. The obtained data on the profile of micro-RNAs in RA makes it possible to distinguish the most “interesting” micro-RNAs for further study of pathogenesis, their role in inflammation, to study the choice of TNF-α inhibitors, and predicting the effectiveness of that treatment.

Hepatoprotective activity of Averrhoa bilimbi L. fruit extract on carbon tetrachloride-induced acute liver faiure in Wistar rats

Background Acute liver failure (ALF) is a state of rapid and progressive deterioration of liver function. Continuous exposure to chemicals and viruses can increase reactive oxygen species (ROS) which leads to prolonged inflammation due to the production of tumor necrosis factor-alpha (TNF-á) thus inhibiting the production of platelet-derived growth factor (PDGF). The objective of this study was to evaluate the effect of administration of Averrhoa bilimbi L. fruit extract on PDGF levels and TNF-á levels in carbon tetrachloride (CCl4)-induced ALF rats. MethodsThis study used a post-test-only control group design involving 20 Wistar rats. They were randomized into 4 groups, namely sham, control, T1, and T2. Group T1 was exposed to CCl4 with the administration of A. bilimbi fruit extract at a dose of 500mg/kgBW, while, group T2 was exposed to CCl4 and given A. bilimbi fruit extract of 750 mg/kgBW. On the 15th day, the serum was analyzed to determine the levels of PDGF and TNF-á using ELISA. ResultsThe highest mean PDGF level in the control group was 146.60±15.36 pg/mL, while the highest mean TNF-á level in group T1 was 40.11±4.44 pg/mL. The One-way ANOVA test showed that there were significant differences in TNF-á (p=0.002) and PDGF (p=0.000) levels between the study groups. ConclusionThe administration of A.bilimbi L. fruit extract affected PDGF and TNF-á levels in CCl4-induced ALF rats. The present study revealed that A. bilimbi fruits have significant hepatoprotective activity in experimental Wistar rats.