MCP-1 Expression Research Articles

Deficiency of tenascin-C attenuated cardiac injury by inactivating TLR4/NLRP3/caspase-1 pathway after myocardial infarction

Inflammation and pyroptosis play a deleterious role in cardiac dysfunction after myocardial infarction (MI). NLRP3/caspase-1 is a well-established axis in pyroptosis and inflammation. In this study, we examined the effects of TN-C on pyroptosis through NLRP3 is unclear. We constructed 18 TN-C-knockout and 38 WT male mice model and divided into WT sham (n = 16), WT MI (n = 22), TNKO sham (n = 6), TNKO MI (n = 12). Elisa, immunostaining, TTC, qPCR, CCK8, flow cytometry, and western blot, echocardiographic, TUNEL staining technologies were applied. Here, we found a positive correlation between TN-C and NLRP3 in heart tissue via the GEPIA database (r = 0.52, p < 0.05). The findings indicate that TN-C was elevated and peaked on the fifth day after MI. TN-C deficiency alleviated cardiac dysfunction (LVEF, FS, LVIDd, and LVIDs) and cardiomyocyte death. Though the intracellular levels of pyroptosis-related cytokine caspase-1, cleaved caspase-1, NLRP3, IL-18, IL-1β were upregulated both in MI and H2O2 stimulation, knockout of TN-C resisted such injury and alleviated cardiac pyroptosis, which further decreased IL-6, TNF-α, MCP-1 expression. TN-C knockdown inhibited TLR4 expression, reduces the release of downstream factors by inactivating the TLR4/NF-kB pathway, while protects the cardiomyocytes. And TLR4 inhibitor TAK-242 significantly reduced NLRP3 expression levels after MI. We demonstrated for the first time a direct link between MI-induced TN-C upregulation and caspase-1-dependent cardiomyocyte pyroptosis, a process mediated, at least in part, by TLR4/NF-kB/NLRP3 and IL-18, IL-1β signaling pathways. These findings provide new insights into the role of TN-C in post-MI cardiomyocytes' pyroptosis and inflammation.

MiR-143 Mediates the TLR2/NF-κB Pathway to Attenuate AngII-induced Damage to VSMCs

Abdominal aortic aneurysm (AAA) is a perilous vascular disease with inflammatory response as its main feature. It is known that the expression of miR-143 is down-regulated in the human aortic aneurysm. In this study, we investigated the effect of miR-143 on AngII-induced VSMCs to learn the potential mechanisms of miR-143 on AAA at the cellular level. The experimental results showed that the expressions of IL-1β, MCP-1, MMP9/13, TLR2, and NF-κB p65 and the percentage of TUNEL-positive cells in AngII-VSMCs were increased significantly compared with the control group. miR-143 had the opposite result. When the expression of miR-143 was up-regulated, the expression of IL-β, MCP-1, and MMP9/13 and the percentage of TUNEL-positive cells in AngII-VSMCs was suppressed. With the transfection of miR-143 over-expression plasmid, IL-1β, MCP-1, and MMP9/13 and the percentage of TUNEL-positive cells were reversed, compared to the AngII group and the AngII+oe-TLR2+miR-143 mimic group. In AngII-induced mouse VSMC, the up-regulation of the miR-143 expression could inactivate the TLR2/NF-κB pathway, thereby alleviating inflammatory response, ECM degradation, and cell apoptosis.

Internalization of Neutrophil-Derived Microvesicles Modulates TNFα-Stimulated Proinflammatory Cytokine Production in Human Fibroblast-Like Synoviocytes.

Neutrophil-derived microvesicles (NDMVs) have the potential to exert anti-inflammatory effects. Our study aimed to explore the effects of NDMVs on proinflammatory cytokines expressed by tumor necrosis factor α (TNFα)-stimulated fibroblast-like synoviocytes (FLS). FLS were isolated from the synovium of knee osteoarthritis (OA) patients undergoing surgery. NDMVs, isolated from TNFα-stimulated healthy neutrophils, were characterized by electron microscopy and nanoparticle tracking analysis. MTT and scratch wound healing assays were used to measure FLS viability and migration after treatment with NDMVs, while internalization of fluorescently labeled NDMVs was appraised by flow cytometry and confocal microscopy. Levels of proinflammatory cytokines in supernatants were quantified by the Bio-Plex system. Incubation of FLS with NDMVs at a vesicle/cell ratio of 100 resulted in a time-dependent uptake, with 35% of synoviocytes containing microvesicles over a 6–24 h time period, with no significant change in cell viability. TNFα stimulated the cytokine expression in FLS, and NDMVs down-regulated TNFα-induced expression of IL-5, IL-6, IL-8, MCP-1, IFNγ and MIP-1β. However, this down-regulation was selective, as NDMVs had no significant effects on TNFα-stimulated expression of IL-2 or IL-4. NDMVs were internalized by FLS to inhibit TNFα-stimulated broad-spectrum proinflammatory cytokine secretion. NDMVs, therefore, may exhibit an anti-inflammatory role in the regulation of the FLS function.

Diacerein Inhibits Myopia Progression through Lowering Inflammation in Retinal Pigment Epithelial Cell.

Myopia is a highly prevalent refractive disorder. We investigated the effect of diacerein on monocular form deprivation (MFD) in hamsters as a possible therapeutic intervention. Diacerein is an anthraquinone derivative drug whose active metabolite is rhein. Diacerein or atropine was applied to the MFD hamsters, and their refractive error and axial length were measured after 21 days. The refractive error (control: −0.91 ± 0.023, atropine: −0.3 ± 0.08, and diacerein: −0.27 ± 0.07 D) and axial length (control: 0.401 ± 0.017, atropine: 0.326 ± 0.017, and diacerein: 0.334 ± 0.016 mm) showed statistically significant differences between control, atropine-treated, and diacerein-treated MFD eyes. Furthermore, we determined the level of transforming growth factor-beta- (TGF-) β1, matrix metalloproteinase- (MMP-) 2, type I collagen, interleukin- (IL-) 6, IL-8, and monocyte chemoattractant protein- (MCP-) 1 in the retina. Atropine and diacerein suppressed levels of the myopia-related TGF-β1 and MMP-2 while increasing type I collagen expression. They also inhibited the interleukin IL-6, IL-8, and MCP-1 levels. Diacerein reduced the IL-6, IL-8, and MCP-1 expression in ARPE-19 cells. Furthermore, diacerein inhibited inflammation by attenuating the phosphorylation of protein kinase B (AKT) and nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) pathway. This suggests that diacerein has a therapeutic effect on myopia and is a potential treatment option.

Comparative cytokine profiling identifies common and unique serum cytokine responses in acute chikungunya and dengue virus infection

BackgroundInfection by chikungunya (CHIKV) and dengue virus (DENV) can cause a wide spectrum of clinical features, many of which are undifferentiated. Cytokines, which broadly also include chemokines and growth factors, have been shown to play a role in protective immunity as well as DENV and CHIKV pathogenesis. However, differences in cytokine response to both viruses remain poorly understood, especially in patients from countries where both viruses are endemic. Our study is therefore aimed to provide a comparative profiling of cytokine response induced by acute DENV and CHIKV infections in patients with similar disease stages and in experimental in vitro infections.MethodsBy using multiplex immunoassay, we compared host cytokine profiles between acute CHIKV and DENV infections by analysing serum cytokine levels of IL-1α, IL-4, IL-5, IL-8, IL-13, RANTES, MCP-3, eotaxin, PDGF-AB/BB, and FGF-2 from the sera of acute chikungunya and dengue fever patients. We further investigated the cytokine profile responses using experimental in vitro CHIKV and DENV infections of peripheral blood mononuclear cells (PBMCs).ResultsWe found that both CHIKV and DENV-infected patients had an upregulated level of IL-8 and IL-4, with the highest IL-4 level observed in DENV-2 infected patients. Higher IL-8 level was also correlated with lower platelet count in dengue patients. IL-13 and MCP-3 downregulation was observed only in chikungunya patients, while conversely PDGF-AB/BB and FGF-2 downregulation was unique in dengue patients. Age-associated differential expression of IL-13, MCP-3, and IL-5 was also observed, while distinct kinetics of IL-4, IL-8, and FGF-2 expression between CHIKV and DENV-infected patients were identified. Furthermore, the unique pattern of IL-8, IL-13 and MCP-3, but not IL-4 expression was also recapitulated using experimental in vitro infection in PBMCs.ConclusionsTaken together, our study identified common cytokine response profile characterized by upregulation of IL-8 and IL-4 between CHIKV and DENV infection. Downregulation of IL-13 and MCP-3 was identified as a unique cytokine response profile of acute CHIKV infection, while distinct downregulation of PDGF-AB/BB and FGF-2 characterized the response from acute DENV infection. Our study provides an important overview of the host cytokine responses between CHIKV and DENV infection, which is important to further understand the mechanism and pathology of these diseases.

Anti Human CX3CR1 VHH Molecule Attenuates Venous Neointimal Hyperplasia of Arteriovenous Fistula in Mouse Model.

Fractalkine receptor 1 (CX3CR1) mediates macrophage infiltration and accumulation, causing venous neointimal hyperplasia (VNH)/venous stenosis (VS) in arteriovenous fistula (AVF). The effect of blocking CX3CR1 using an anti-human variable VHH molecule (hCX3CR1 VHH, BI 655088) on VNH/VS was determined using a humanized mouse in which the human CX3CR1 (hCX3CR1) gene was knocked in (KI). Whole-transcriptomic RNA sequencing with bioinformatics analysis was used on human stenotic AVF samples, C57BL/6J, hCX3CR1 KI mice with AVF and CKD, and in in vitro experiments to identify the pathways involved in preventing VNH/VS formation after hCX3CR1 VHH administration. Accumulation of CX3CR1 and CD68 was significantly increased in stenotic human AVFs. In C57BL/6J mice with AVF, there was increased Cx3cr1, Cx3cl1, Cd68, and Tnf-α gene expression, and increased immunostaining of CX3CR1 and CD68. In hCX3CR1-KI mice treated with hCX3CR1 VHH molecule (KI-A), compared with vehicle controls (KI-V), there was increased lumen vessel area and patency, and decreased neointima in the AVF outflow veins. RNA-seq analysis identified TNF-α and NF-κB as potential targets of CX3CR1 inhibition. In KI-A-treated vessels compared with KI-V, there was decreased gene expression of Tnf- α, Mcp-1, and Il-1 β; with reduction of Cx3cl1, NF-κB, and Cd68; decreased M1, Ly6C, smooth muscle cells, fibroblast-activated protein, fibronectin, and proliferation; and increased TUNEL and M2 staining. In cell culture, monocytes stimulated with PMA and treated with hCX3CR1 VHH had decreased TNF- α, CD68, proliferation, and migration. CX3CR1 blockade reduces VNH/VS formation by decreasing proinflammatory cues.

Abstract 2561: Tumorigenic and metabolomic impacts of adipose-derived monocyte chemotactic protein-1 in a model of obesity-enhanced, male breast cancer

Abstract Breast cancer is a rare but aggressive disease in men. Approximately, 90% of all breast cancer in men are invasive carcinomas, 25% of which have distant metastasis at the time of clinical presentation. Obesity is a risk factor for breast cancer. Monocyte chemotactic protein-1 (MCP-1) is an adipose-derived cytokine whose concentrations are elevated by obesity. This study tested the hypothesis that adipose-derived MCP-1 contributes to male breast cancer. In a 2x2 design, male MMTV-PyMT mice with or without adipose specific Mcp-1 knockdown [designated as Mcp-1-/- or wild-type (WT)] were fed the standard AIN93G diet or an obesogenic, high-fat diet (HFD) for 25 weeks. The AIN93G diet and HFD contained 16% and 45% of energy from soybean oil, respectively. Mcp-1-/- mice had lower adipose Mcp-1 expression than WT mice. Adipose Mcp-1 deficiency reduced plasma concentrations of MCP-1 in mice fed the HFD. Mice fed the HFD had a greater tumor progression rate than mice fed the AIN93G diet (4679% vs 2430%), regardless of genotype. Mcp-1-/- mice, compared to WT mice, had a longer tumor latency (25.2 weeks vs 18.0 weeks) and lower tumor incidence (19% vs 56%), tumor progression rate (2317% vs 4792%), and tumor weights (0.23 g vs 0.64 g). Metabolomic analysis of plasma identified 87 metabolites, 56 of which differed among the four groups, including 24 that differed between the diets and 22 that differed between the genotypes. Sparse partial least squares-discriminant analysis identified 10 major metabolites that were altered the most among the four groups. These included amino acids (alanine, isoleucine, leucine, phenylalanine, threonine, and valine) and carbohydrate metabolites (fumaric acid, glucuronic acid, hexuronic acid, and malic acid). The integrated pathway analysis of the 87 identified metabolites showed that protein biosynthesis and carbohydrate metabolism pathways are the most disturbed in MMTV-PyMT mice. In conclusion, adipose-derived MCP-1 contributes to mammary tumorigenesis and alters metabolism in male MMTV-PyMT mice. Citation Format: Lin Yan, Sneha Sundaram, Bret M. Rust, Matthew J. Picklo, Michael R. Bukowski. Tumorigenic and metabolomic impacts of adipose-derived monocyte chemotactic protein-1 in a model of obesity-enhanced, male breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2561.

Imperatae rhizoma-Hedyotis diffusa Willd. herbal pair alleviates nephrotic syndrome by integrating anti-inflammatory and hypolipidaemic effects

BackgroundNephrotic syndrome (NS) is a common nephropathy with a complex and diverse aetiology. Both Imperatae rhizoma and Hedyotis diffusa Willd. are herbs that are widely used as medicine and functional food. In traditional Chinese medicine theory, they are used as an herbal pair (HP) to treat inflammation-related diseases in the clinic, especially disorders of the kidney. PurposeThis study aimed to investigate the anti-inflammatory and hypolipidaemic effects of HP in an NS rat model and provide scientific data for its clinical application. MethodsAn NS model was established by two-dose injection of Sprague-Dawley rats with adriamycin. Seven groups, including the sham, model, HP treatment (0.25, 0.5 and 1.0 g/kg/d), prednisone (positive control, 5 mg/kg/d), and atorvastatin (positive control, 4 mg/kg/d) groups, were tested. The biochemical indexes of renal function and inflammatory cytokines were determined by ELISA kits and/or qPCR assays, and the crucial protein involved in the signalling pathway were subsequently tested by qPCR and/or Western blotting. Based on specific compounds identified by LC-Q-TOF-MS, network pharmacological study was carried out. ResultsThe levels of BUN, Scr, Upro, UA, Alb, TC, TG, and LDL-C were significantly elevated in model rats. HP treatment for four weeks improved the renal function and the dyslipidaemia by decreasing the levels of all parameters, except BUN and Scr. HP treatment (0.5 and 1.0 g/kg/d) upregulated the expression of PPARγ, CYP7b1, and LDLR in the liver, while it down-regulated PCSK9, showing a regulatory effect on lipid metabolism disorder. The levels of TNF-α and IL-1β in the plasma and the mRNA expression of TNF-α, IL-1β, MCP-1, and TGF-β1 in the kidney were decreased in HP groups, revealing its anti-inflammatory effect in NS rats. The HP exerted an alleviation effect on the inflammatory response through the NF-κB pathway by inhibiting the mRNA and protein expression of p50 and p65. There were 34 compounds identified or tentatively characterized in HP. In the network pharmacological study, PPARG(PPARγ), PCSK9, RELA(p65), and NF-κB1(p50) were the top 20 targets for HP, supporting the animal experimental results. Conclusion: HP exhibited protective effects on NS rats. These effects might be closely related to the inhibition of NF-κB and PCSK9-LDLR and activation of the PPARγ-CYP7B1 signalling pathways.

Increased epithelial galectin-13 expression associates with eosinophilic airway inflammation in asthma.

Airway eosinophilic inflammation is a central feature in asthma which is mainly driven by type 2 response. The expression of galectin-13 was up-regulated in a parasitic infection model which is also characterized by type 2 immune response. We hypothesized that galectin-13 may be involved in airway eosinophilic inflammation in asthma. To unveil the role of galectin-13 in asthma airway inflammation. We measured galectin-13 expressions in bronchial brushings, sputum, and plasma of asthma patients (n=54) and healthy controls (n=15), and analysed the correlations between galectin-13 expression and airway eosinophilia. We used human bronchial epithelial cell line 16HBE to investigate the possible mechanism by which galectin-13 participates in eosinophilic inflammation. The expression of galectin-13 was markedly increased in subjects with asthma compared to controls. Epithelial galectin-13 mRNA levels in asthmatic subjects were strongly correlated with eosinophilic airway inflammation (the percentage of sputum eosinophils, the number of eosinophils in bronchial submucosa and FeNO) and the expression of Th2signature genes (CLCA1, POSTN and SERPINB2). Inhaled corticosteroid (ICS) treatment reduced plasma galectin-13 levels, and baseline plasma galectin-13levels reflect the response to ICS treatment. In cultured 16HBE cells, knockdown of galectin-13suppressed IL-13-stimulated MCP-1 and eotaxin-1 expression by inhibiting the activation of EGFR and ERK. Galectin-13 is a novel marker for airway eosinophilia in asthma, and may contribute to allergic airway eosinophilic inflammation by up-regulating the expression of MCP-1 and eotaxin-1. Plasma galectin-13levels may be useful for predicting responses to ICS treatment.

Phosphodiesterase 10A Is a Key Mediator of Lung Inflammation.

Cyclic nucleotides cAMP and cGMP are important regulators of immune cell functions. Phosphodiesterases (PDEs) hydrolyze cAMP and/or cGMP and, thus, play crucial roles in cyclic nucleotide homeostasis. Abnormal alterations of PDE expression have been implicated in several diseases. To understand the function of PDEs in macrophages, we screened for all PDE genes in both peritoneal and alveolar macrophages from C57BL/6J mice and found that PDE4B and PDE10A are highly induced by LPS. A number of PDE4 inhibitors have been used clinically for the treatment of inflammatory lung diseases. However, the role of PDE10A in inflammation is still poorly understood. We therefore investigated the role of PDE10A in macrophage inflammatory response in vitro and acute lung inflammation in vivo. We found that LPS induces a sustained PDE10A expression in macrophages, which is different from a transient induction by PDE4B. PDE10A inhibition blocked LPS-induced MCP-1 expression, but not TNF-α, whereas PDE4B inhibition blocked LPS-induced TNF-α expression, but not MCP-1. In addition, PDE10A inhibition or deficiency decreased LPS-induced HIF-1α protein expression and subsequently suppressed MCP-1 expression. In vivo, PDE10A expression was also elevated in lung tissue after LPS exposure. Global PDE10A knockout or systemic administration of the PDE10A inhibitor TP-10 in mice significantly suppressed inflammatory molecule levels in the lung tissue and bronchoalveolar lavage fluid as well as inflammatory cell infiltration. These findings show that PDE10A plays a critical role in lung inflammation by promoting the activation of resident macrophages and infiltration of neutrophils.

Nicotinamide mononucleotide-elicited NAMPT signaling activation aggravated adjuvant-induced arthritis in rats by affecting peripheral immune cells differentiation

Supplement of nicotinamide mononucleotide (NMN), the direct precursor of nicotinamide adenine dinucleotide (NAD+) has gained prominence due to the significant anti-aging potentials of nicotinamide phosphoribosyltransferas (NAMPT)/NAD+ signaling. Because over-expression of NAMPT is deeply implicated in inflammatory arthritis, we investigated the effects of NMN supplement on rats with adjuvant-induced arthritis (AIA). Tested rats were given oral treatment of NMN at 200 mg/kg/day for 25 days. Arthritis score and body weight were periodically recorded. Clinical outcomes were evaluated based on arthritic manifestations, ELISA analysis and histological examination. T cells subsets were analyzed by flow cytometry. Expressions of protein and mRNA were assessed by immunoblotting and PCR methods, respectively. Levels of CD172a, CD43, and NAMPT in peripheral blood mononuclear cells (PBMCs) were investigated by immunofluorescence approach. Obtained results were further validated by experiments in vitro. Generally, NMN exacerbated AIA severity in rats. It deteriorated MMP3-controlled tissues damages, and altered immune profile by increasing Th17/Treg cells ratio. The up-regulation of NAMPT in PBMCs from NMN-treated rats was confirmed by both immunofluorescence and PCR experiments, which was synchronized with significant increase in iNOS, MCP-1, IL-1β expression. NMN-primed AIA PBMCs were potent in up-regulating MCP-1, IL-1β, MMP3 and p-JNK expression in synovioblast. NMN stimulus barely affected Th17 cells count in in vitro cultured splenocytes, but it greatly potentiated the capability of AIA monocytes in inducing IL-17α secretion and Th17 cells differentiation in the co-cultured splenocytes. It suggested that long-term NMN supplement could exacerbate inflammatory arthritis by reshaping the immune milieu through the up-regulation of NAMPT.

CD38 deficiency up-regulated IL-1β and MCP-1 through TLR4/ERK/NF-κB pathway in sepsis pulmonary injury

As a disease with high mortality, many cytokines and signaling pathways are associated with sepsis. The pro-inflammatory cytokines and chemokines are participating in the pathogenesis of sepsis, especially in early stage. Moreover, the releases and expressions of cytokines are regulated by numerous signaling pathways, including TLR4/ERK pathway. But despite many studies have expounded the pathogenesis of sepsis and the regulation of cytokines in sepsis, how CD38 influence the expressions of related molecules in sepsis are still unknown. The aim of this study is illuminating the alteration of cytokines and signaling pathways in CD38−/− mice injected with Escherichia coli. Compared with WT mice, E. coli infection results in more severe pulmonary injuries and higher mRNA expressions of cytokines. Compared with E. coli infected WT mice, CD38 knockout leads to aggravated pulmonary injury, increased phosphorylated ERK1/2, p38 and NF-κB p65, and enhanced levels of IL-1β, iNOS and MCP-1. While compared with E. coli infected CD38−/− mice, TLR4 mutation results in alleviated pulmonary injury, down-regulated phosphorylated ERK1/2 and NF-κB p65, and decreased expressions of IL-1β and MCP-1. CD38 deficiency increased the expressions of IL-1β andMCP-1 and aggravated pulmonary injury through TLR4/ERK/NF-κB pathway in sepsis.

Epac activation ameliorates tubulointerstitial inflammation in diabetic nephropathy.

Tubulointerstitial inflammation plays an important role in the progression of diabetic nephropathy (DN), and tubular epithelial cells (TECs) are crucial promoters of the inflammatory cascade. Exchange protein activated by cAMP (Epac) has been shown to suppress the angiotensin II (Ang-II)-induced release of inflammatory cytokines in tubular cells. However, the role of Epac in TEC-mediated tubulointerstitial inflammation in DN remains unknown. We found that administering the Epac agonist 8-pCPT-2'-O-Me-cAMP (8-O-cAMP) to db/db mice inhibited tubulointerstitial inflammation characterized by macrophage infiltration and increased inflammatory cytokine release and consequently alleviated tubulointerstitial fibrosis in the kidney. Furthermore, 8-O-cAMP administration restored CCAAT/enhancer binding protein β (C/EBP-β) expression and further upregulated the expression of Suppressor of cytokine signaling 3 (SOCS3), while inhibiting p-STAT3, MCP-1, IL-6, and TNF-α expression in the kidney cortex in db/db mice. And in vitro study showed that macrophage migration and MCP-1 expression induced by high glucose (HG, 30 mM) were notably reduced by 8-O-cAMP in human renal proximal tubule epithelial (HK-2) cells. In addition, 8-O-cAMP treatment restored C/EBP-β expression in HK-2 cells and promoted C/EBP-β translocation to the nucleus, where it transcriptionally upregulated SOCS3 expression, subsequently inhibiting STAT3 phosphorylation. Under HG conditions, siRNA-mediated knockdown of C/EBP-β or SOCS3 in HK-2 cells partially blocked the inhibitory effect of Epac activation on the release of MCP-1. In contrast, SOCS3 overexpression inhibited HG-induced activation of STAT3 and MCP-1 expression in HK-2 cells. These findings indicate that Epac activation via 8-O-cAMP ameliorates tubulointerstitial inflammation in DN through the C/EBP-β/SOCS3/STAT3 pathway.

DNAJB3 Deficiency Exacerbates Diet-Induced Obesity and Insulin Resistance

ObjectivesThe prevalence of obesity and Type 2 Diabetes (T2D) continues to rise worldwide, leading to many other chronic diseases and imposing a large economic burden. DNAJ, also known as HSP40 (Heat Shock Protein-40), subfamily B, member 3 (DNAJB3), is a chaperone protein that can be induced under various stressors. Recent reports implicated DNAJB3 in protection against obesity and T2D. Specifically, DNAJB3 was downregulated in some patients with obesity and T2D; however, precise underlying mechanisms remained unclear. We hypothesized that lack of DNAJB3 will increase body weight and body fat, inflammation, glucose intolerance and insulin resistance in diet-induced obese mice, compared to B6 wild type (WT) littermates fed the same diets. MethodsThree DNAJB3 knockout (KO) mutant lines were generated at the Pennington Biomedical Research Center (KO 30, 44 and 47). Male and female KO and wild type (WT) littermates were fed a high fat diet (45% kcal fat) for 12 weeks. Body weight and composition were measured weekly, and a glucose tolerance test (GTT) was conducted. Following euthanasia, blood, adipose and muscle tissues were harvested and used for serum analyses and tissue gene/protein expression, respectively. ResultsCompared to WT, only DNAJB3 KO male and female mice of line 47 demonstrated significantly higher body weight and fat mass (P < 0.05). Similarly, line 47 also showed a lower rate of glucose clearance as measured by GTT. Consistent with increased body weight and fat mass, male mice in line 47 also exhibited significantly higher mRNA levels of inflammatory markers including TNFα and IL-1β, in gonadal fat, compared to WT and lines 30 and 44. Moreover, similar trends towards increased TNF-α and MCP-1 expression was observed in muscle tissues of KO males of line 47, when compared to WT (P < 0.47), and line 30 (P < 0.15) respectively. ConclusionsAbsence of DNAJB3, increases adiposity, glucose intolerance and inflammation in diet-induced obese mice in both males and females. these findings suggest that DNAJB3 plays an important role in metabolic functions and glucose homeostasis, which warrants further research as a potential therapeutic target for obesity and T2D. Funding SourcesFunded by Qatar National Research Funds, Hamad Bin Khalifa University & Qatar Biomedical Research Institute, Qatar.

1141-P: Short-Chain Fatty Acid Acetate Increases TNF-a-Induced MCP-1 Production in Monocytes via the ACSL-1/MAPK/NF-?B Axis: Significance for Inflammation and Insulin Resistance

Short-chain fatty acids (SCFAs) are formed as by-products of dietary fiber metabolism by gut bacteria and have multiple immunomodulatory functions in different cells involved in the inflammatory and immune responses. In general, the anti-inflammatory role of SCFAs is well documented. Here, we investigated whether SCFAs could modulate the TNF-α-mediated induction of chemokine MCP-1 (also known as CCL2) in monocytes/macrophages; and if so, which mechanisms were involved. Monocytic cells were exposed to SCFAs including acetate, propionate, and butyrate, with or without TNF-α, and the release of MCP-1 was measured. We found that none of the SCFAs suppressed TNF-α-induced MCP-1 release in monocytes. However, challenge with acetate in combination with TNF-α resulted in substantially greater MCP-1 release from monocytic cells than challenge with TNF-α alone, indicating synergistic effects. Interestingly, such effects of acetate were not seen in macrophages. Synergistic upregulation of MCP-1 was mediated through the activation of acyl-CoA synthetase 1 (ACSL1). Acetate/TNFα induced phosphorylation of p38, ERK1/2, and NF-κB was observed during the secretion of MCP-1. Acetate/TNF-α mediated synergistic expression of MCP-1 was significantly reduced by the inhibition of p38 MAPK, ERK1/2 and NF-κB signaling pathways. Furthermore, inhibition of the ACSL1 activity also attenuates the TNF-α-mediated phosphorylation of p38 MAPK, ERK1/2, and NF-κB. ACSL1 inhibition led to a lower induction of NF-κB/AP-1 activity in response to co-stimulation with acetate and TNF-α. In conclusion, these data support the proinflammatory, rather than anti-inflammatory, effects of acetate on TNF-α-mediated MCP-1 expression in monocytes involving the ACSL1/MAPK/NF-kB axis. These findings point to the differential effects of SCFA acetate in the settings of obesity and metabolic inflammation/insulin resistance. Disclosure R. Ahmad: None. A. Abu alroub: None. F. Alrashed: None. A. Al-sayyar: None. N. Akhter: None. S. P. Kochumon: None. F. Almulla: None. S. T. Sindhu: None.

Expression and clinical significance of MCP-1 in serum of patients with chronic kidney disease undergoing maintenance hemodialysis.

Expression and clinical significance of MCP-1 in serum of patients with chronic kidney disease undergoing maintenance hemodialysis.

MiR-154-5p-MCP1 Axis Regulates Allergic Inflammation by Mediating Cellular Interactions.

In a previous study, we have demonstrated that p62, a selective receptor of autophagy, can regulate allergic inflammation. In the present study, microRNA array analysis showed that miR-154-5p was increased by antigen (DNP-HSA) in a p62-dependent manner in rat basophilic leukemia cells (RBL2H3). NF-kB directly increased the expression of miR-154-5p. miR-154-5p mediated in vivo allergic reactions, including passive cutaneous anaphylaxis and passive systemic anaphylaxis. Cytokine array analysis showed that antigen stimulation increased the expression of MCP1 in RBL2H3 cells in an miR-154-5p-dependent manner. Reactive oxygen species (ROS)-ERK-NF-kB signaling increased the expression of MCP1 in antigen-stimulated RBL2H3 cells. Recombinant MCP1 protein induced molecular features of allergic reactions both in vitro and in vivo. Anaphylaxis-promoted tumorigenic potential has been known to be accompanied by cellular interactions involving mast cells, and macrophages, and cancer cells. Our experiments employing culture medium, co-cultures, and recombinant MCP1 protein showed that miR-154 and MCP1 mediated these cellular interactions. MiR-154-5p and MCP1 were found to be present in exosomes of RBL2H3 cells. Exosomes from PSA-activated BALB/C mouse induced molecular features of passive cutaneous anaphylaxis in an miR-154-5p-dependent manner. Exosomes from antigen-stimulated RBL2H3 cells enhanced both tumorigenic and metastatic potentials of B16F1 melanoma cells in an miR-154-5p-dependent manner. Exosomes regulated both ROS level and ROS mediated cellular interactions during allergic inflammation. Our results indicate that the miR-154-5p-MCP1 axis might serve as a valuable target for the development of anti-allergy therapeutics.

MO919THE INTERPLAY BETWEEN IL-6 AND IL-17 MIGHT PLAY A SIGNIFICANT ROLE IN CHRONIC ANTIBODY MEDIATED REJECTION IN RENAL ALLOGRAFT RECIPIENTS

Abstract Background and Aims Chronic antibody-mediated rejection (CABMR) plays a critical role in kidney allograft loss and consider among one of the most important barriers that is responsible for late term graft loss. Previously we believed that alloreactive T-cell and de-novo DSA responsible for late term graft loss but recent study suggested that not only immune cell, non-immune cells like fibroblast also plays important role in chronic inflammation and allograft rejection via IL-6 amplifier loop (IL-6+IL-17). The interaction between non-immune tissues/cells and the immune system plays a critical role in chronic inflammation and late graft rejection. In chronic inflammation IL-6 enhance the production of acute phase proteins, T cell Subset differentiation, Maturation of Plasma cells, Generation of cellular and humoral immune responses and Control the transition from acute to chronic inflammation by changing the nature of leucocyte infiltration (from neutrophils to monocyte). We sought to see whether IL-6 and IL-17A mediated synergistic activation of inflammation amplifier is operational in CABMR. Method Recruitment of patients according to Banff 2017criteria and biopsy was taken from consented patients and establishment of fibroblast culture from renal biopsy of patients with CABMR. Fibroblast culture from CABMR patients were cultured to purity and pre stimulated with IL-6 (20ng/ µl), IL-17(50ng/ µl), IL-6 plus IL-17 for 24 hours and culture supernatant were collected for IL-6 ELISA to see synergistic activation. Serum IL-6, MCP1 and CCL20 levels of Healthy control (HC), CABMR and Non-CABMR patients and MCP1, CCL20 level in culture supernatant were measured by ELISA. m-RNA expression of IL-6, MCP1, CCL20 and SOCS3 gene were measured by real time PCR (Syber-green method) One-way ANOVA and Non-parametric Student t tests (two-tailed) were used for the statistical analysis of differences between groups. Results In comparison to IL-6 and IL-17 alone these cytokines synergistically induced more IL-6 production from renal fibroblasts. (Fig 1) also, we found that concentrations of effectors of inflammation amplifiers like IL-6, CCL-20 &amp; MCP-1 in sera were significantly higher in CABMR patients compared to Non rejection patients, while their concentration in culture supernatant was higher when fibroblast cell stimulated with IL-6 and IL-17 together as compared either IL-6 or IL-17 alone. (Fig 2) Gene expression analysis of IL-6, MCP1 and CCL20 was significant higher (p&amp;lt;0.001) with synergistic activation of IL-6 and IL-17 as compared to either IL-6 or IL-17 alone, while SOCS3 gene expression was downregulated. (Fig 3) There was significant reduction in IL-6 concentration in culture supernatant with IL-6 and IL-17 inhibitor together (Fig 4) and m-RNA expression of IL-6 and MCP-1 was significantly reduced. (Fig 5) Conclusion CABMR is perpetuated by inflammation amplifier loop or synergistic induction of IL-6 and IL-17. Inhibition of IL-6 with Anti-IL-6 (Tocilizumab) and IL-17 with Anti-IL-17 reduces the tissue injury marker (IL-6, MCP1, CCL20) and allograft rejection.

MO334ERYTHROPOIETIN-STIMULATED HUMAN ENDOTHELIAL PROGENITOR CELLS AMELIORATE INFLAMMATION AND FIBROSIS VIA INFLAMMASOME IN ISCHEMIA/REPERFUSION-INDUCED ACUTE KIDNEY INJURY

Abstract Background and Aims Ischemia/reperfusion-induced AKI (IR-AKI) is a major cause of AKI and progress to chronic kidney disease. But an effective therapeutic intervention for IR-AKI is not established yet. Erythropoietin (EPO) is a potent stimulator of erythroid progenitor cells and is significantly upregulated during hypoxia. Endothelial progenitor cells (EPCs) are derived from the bone marrow or tissue-resident cells and play major roles in the maintenance of vascular integrity and the repair of endothelial damage. So, we investigated if EPO-stimulated human EPCs could have the renoprotective effects in an IR-AKI mouse model. Method EPCs originated from human peripheral blood were cultured with EPO (10 IU/mL). Mice were assigned to sham, IR only groups, IR with EPC, and IR with EPO-treated EPC. EPCs (5x105 cells, tail vein) were administered twice at 30 min prior to bilateral renal artery occlusion, and 5 min before reperfusion, with all mice sacrificed 24 h after IR-AKI. Results Both EPCs and EPO-treated EPCs significantly attenuated the renal dysfunction associated with IR-AKI, as well as tissue injury. Apoptotic cell death and oxidative stress were significantly reduced in EPC and EPO-treated EPC mice. Expression of PCNA, ICAM-1, MCP-1 and α-SMA were also significantly reduced in EPC and EPO-treated EPC mice. Furthermore, the expression of NLRP3 and caspase-1 via the activation of NF-κB signaling pathways were significantly reduced in EPC and EPO-treated EPC mice. These results show more effective in EPO-treated EPC than EPC alone and suggest EPO might be involved in the development of EPC. Conclusion This study provides that inflammasome-mediated inflammation and fibrosis might be a potential target of EPC as a treatment for IR-AKI.

SETD8 involved in the progression of inflammatory bowel disease via epigenetically regulating p62 expression.

Epigenetic modification is an important part of the pathogenesis of inflammatory bowel disease (IBD). Some studies proved that p62 was involved in inflammatory response and upregulated in IBD patients, and histone modification plays an important role in regulating p62 expression. SETD8, a histone H4K20 methyltransferase, has been reported downregulated in some inflammatory diseases. Here, we investigated the role of SETD8 in the development of IBD and its underlying mechanisms. An inflammatory cell model was established to elucidate whether SETD8 involved in inflammatory response in macrophages. Three percent dextran sodium sulfate-induced colitis murine model injection with SETD8 inhibitor was used in our study to investigate whether SETD8 inhibition can affect the progress of IBD. The expression of SETD8 and p62 was measured by qRT-PCR and western blot. The mRNA level of inflammatory cytokines was analyzed by qRT-PCR. In addition, chromatin immunoprecipitation-PCR was performed to identify the mechanism by which SETD8 regulates p62. SETD8 expression obviously decreased in vitro, in vivo models and in IBD patients. In lipopolysaccharide-activated RAW264.7 cells, knockdown of SETD8 significantly increased the mRNA expression of inducible nitric oxide synthase, cyclooxygenase-2, TNF-α, IL-6, IL-1β, and MCP-1. Based on the dataset, we verified that p62 was a target gene of SETD8 and chromatin immunoprecipitation-PCR assay identified that silence of SETD8 distinctly decreases the H4K20me1 enrichment in the promoter of p62. Moreover, silencing of p62 partly reverses the SETD8 inhibition-mediated pro-inflammatory effect in vitro. Finally, SETD8 pharmacological inhibitor (UNC0379) aggravated the disease progression in dextran sodium sulfate-induced murine colitis. Our findings elucidate an epigenetic mechanism by which SETD8 regulates the p62 expression and restrains the inflammatory response in colitis. Our result suggests that targeting SETD8 may be a promising therapy for IBD.