mRNA Levels Of Pro-inflammatory Genes Research Articles

Dietary sugar kelp (Saccharina latissima) consumption did not attenuate atherosclerosis in low-density lipoprotein receptor knockout mice.

We previously demonstrated the beneficial effects of U.S.-grown sugar kelp (Saccharina latissima), a brown seaweed, on reducing serum triglycerides (TG) and total cholesterol (TC) and protecting against inflammation and fibrosis in the adipose tissue of diet-induced obesity mice. In this current study, we aimed to explore whether the dietary consumption of sugar kelp can prevent atherosclerosis using low-density lipoprotein receptor knockout (Ldlr KO) mice fed an atherogenic diet. Eight-week-old male Ldlr KO mice were fed either an atherogenic high-fat/high-cholesterol control (HF/HC) diet or a HF/HC diet supplemented with 6% (w/w) sugar kelp (HF/HC-SK) for 16 weeks. Consumption of sugar kelp significantly increased the body weight gain without altering fat mass and lean mass. Also, there were no significant differences in energy expenditure and physical activities between the groups. The two groups did not show significant differences in serum and hepatic TG and TC levels or the hepatic expression of genes involved in cholesterol and lipid metabolism. Although serum alanine aminotransferase (ALT) activity did not differ significantly between the two groups, there were significant increases in the expression of macrophage markers, including adhesion G protein-coupled receptor E1 and cluster of differentiation 68, as well as tumor necrosis factor alpha in the HF/HC-SK group compared to the HF/HC mice. The consumption of sugar kelp did not elicit a significant effect on the development of aortic lesions. Moreover, lipopolysaccharide-stimulated splenocytes isolated from HF/HC-SK-fed mice showed no significant changes in the mRNA levels of pro-inflammatory genes compared with those from the HF/HC mice. In summary, the consumption of dietary sugar kelp did not elicit anti-atherogenic and hepatoprotective effects in Ldlr KO mice.

Effects of a biotechnologically produced Pleurotus sapidus mycelium on gut microbiome, liver transcriptome and plasma metabolome of broilers

Submerged cultivation using low-value agro-industrial side streams allows large-scale and efficient production of fungal mycelia, which has a high nutritional value. As the dietary properties of fungal mycelia in poultry are largely unknown, the present study aimed to investigate the effect of feeding a Pleurotus sapidus (PSA) mycelium as a feed supplement on growth performance, composition of the cecal microbiota and several physiological traits including gut integrity, nutrient digestibility, liver lipids, liver transcriptome and plasma metabolome in broilers. 72 males, 1-day-old Cobb 500 broilers were randomly assigned to 3 different groups and fed 3 different adequate diets containing either 0% (PSA-0), 2.5% (PSA-2.5) and 5% (PSA-5.0) P. sapidus mycelium in a 3-phase feeding system for 35 d. Each group consisted of 6 cages (replicates) with 4 broilers/cage. Body weight gain, feed intake and feed:gain ratio and apparent ileal digestibility of crude protein, ether extract and amino acids were not different between groups. Metagenomic analysis of the cecal microbiota revealed no differences between groups, except that one α-diversity metric (Shannon index) and the abundance of 2 low-abundance bacterial taxa (Clostridia UCG 014, Eubacteriales) differed between groups (P < 0.05). Concentrations of total and individual short-chain fatty acids in the cecal digesta and concentrations of plasma lipopolysaccharide and mRNA levels of proinflammatory genes, tight-junction proteins, and mucins in the cecum mucosa did not differ between groups. None of the plasma metabolites analyzed using targeted-metabolomics differed across the groups. Hepatic transcript profiling revealed a total of 144 transcripts to be differentially expressed between group PSA-5.0 and group PSA-0 but none of these genes was regulated greater 2-fold. Considering either the lack of effects or the very weak effects of feeding the P. sapidus mycelium in the broilers it can be concluded that inclusion of a sustainably produced fungal mycelium in broiler diets at the expense of other feed components has no negative consequences on broilers´ performance and metabolism.

The Effect of Dietary Supplementation with Probiotic and Postbiotic Yeast Products on Ewes Milk Performance and Immune Oxidative Status.

The administration of yeast products as feed additives has been proven to beneficially affect animal productivity through energy, oxidative, and immune status improvement. This study evaluated a combination of Saccharomyces cerevisiae live yeast (LY) with yeast postbiotics (rich in mannan-oligosaccharides (MOS) and beta-glucans) and selenium (Se)-enriched yeast on ewes' milk performance and milk quality, energy and oxidative status, and gene expression related to their immune system during the peripartum period. Ewes were fed a basal diet (BD; F:C = 58:42 prepartum and 41:59 postpartum) including inorganic Se (CON; n = 27), the BD supplemented with a LY product, and inorganic Se (AC; n = 29), as well as the combination of the LY, a product of yeast fraction rich in MOS and beta-glucans, and organic-Se-enriched yeast (ACMAN; n = 26) from 6 weeks prepartum to 6 weeks postpartum. The β-hydroxybutyric acid concentration in the blood of AC and ACMAN ewes was lower (compared to the CON) in both pre- and postpartum periods (p < 0.010). Postpartum, milk yield was increased in the AC and ACMAN Lacaune ewes (p = 0.001). In addition, the activity of superoxide dismutase (p = 0.037) and total antioxidant capacity (p = 0.034) measured via the 2,2-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) method was increased in the blood plasma of the ACMAN postpartum. Higher ABTS values were also found (p = 0.021), while protein carbonyls were reduced (p = 0.023) in the milk of the treated groups. The relative transcript levels of CCL5 and IL6 were downregulated in the monocytes (p = 0.007 and p = 0.026 respectively), and those of NFKB were downregulated in the neutrophils of the ACMAN-fed ewes postpartum (p = 0.020). The dietary supplementation of ewes with yeast postbiotics rich in MOS and beta-glucans, and organic Se, improved energy status, milk yield and some milk constituents, and oxidative status, with simultaneous suppression of mRNA levels of proinflammatory genes during the peripartum period.

Beneficial Effects of the Direct AMP-Kinase Activator PXL770 in In Vitro and In Vivo Models of X-Linked Adrenoleukodystrophy.

X-linked adrenoleukodystrophy (ALD) is a severe orphan disease caused by mutations in the peroxisomal ABCD1 transporter gene, leading to toxic accumulation of Very Long-Chain Fatty Acids (VLCFA - in particular C26:0) resulting in inflammation, mitochondrial dysfunction and demyelination. AMP-activated protein kinase (AMPK) is downregulated in ALD, and its activation is implicated as a therapeutic target. PXL770 is the first direct allosteric AMPK activator with established clinical efficacy and tolerability. Methods: We investigated its effects in ALD patient-derived fibroblasts/lymphocytes and Abcd1 KO mouse glial cells. Readouts included VLCFA levels, mitochondrial function and mRNA levels of proinflammatory genes and compensatory transporters (ABCD2-3). After PXL770 treatment in Abcd1 KO mice, we assessed VLCFA levels in tissues, sciatic nerve axonal morphology by electronic microscopy and locomotor function by open-field/balance-beam tests. Results: In patients' cells and Abcd1 KO glial cells, PXL770 substantially decreased C26:0 levels (by ∼90%), improved mitochondrial respiration, reduced expression of multiple inflammatory genes and induced expression of ABCD2-3 In Abcd1 KO mice, PXL770 treatment normalized VLCFA in plasma and significantly reduced elevated levels in brain (-25%) and spinal cord (-32%) versus untreated (P < 0.001). Abnormal sciatic nerve axonal morphology was also improved along with amelioration of locomotor function. Conclusion: Direct AMPK activation exerts beneficial effects on several hallmarks of pathology in multiple ALD models in vitro and in vivo, supporting clinical development of PXL770 for this disease. Further studies would be needed to overcome limitations including small sample size for some parameters, lack of additional in vivo biomarkers and incomplete pharmacokinetic characterization. SIGNIFICANCE STATEMENT: Adrenoleukodystrophy is a rare and debilitating condition with no approved therapies, caused by accumulation of very long-chain fatty acids. AMPK is downregulated in the disease and has been implicated as a potential therapeutic target. PXL770 is a novel clinical stage direct AMPK activator. In these studies, we used PXL770 to achieve preclinical validation of direct AMPK activation for this disease - based on correction of key biochemical and functional readouts in vitro and in vivo, thus supporting clinical development.

Long-term persistence of infectious Zika virus: Inflammation and behavioral sequela in mice.

The neurodevelopmental defects associated with ZIKV infections early in pregnancy are well documented, however the potential defects and long-term consequences associated with milder infections in late pregnancy and perinatal period are less well understood. To model these, we challenged 1 day old (P1) immunocompetent C57BL/6 mice with ZIKV. The animals developed a transient neurological syndrome including unsteady gait, kinetic tremors, severe ataxia and seizures 10–15 days post-infection (dpi) but symptoms subsided after a week, and most animals survived. Despite apparent recovery, MRI of convalescent mice show reduced cerebellar volume that correlates with altered coordination and motor function as well as hyperactivity and impulsivity. Persistent mRNA levels of pro-inflammatory genes including Cd80, Il-1α, and Ifn-γ together with Cd3, Cd8 and perforin (PrfA), suggested persistence of low-grade inflammation. Surprisingly, the brain parenchyma of convalescent mice harbor multiple small discrete foci with viral antigen, active apoptotic processes in neurons, and cellular infiltrates, surrounded by activated astrocytes and microglia as late as 1-year post-infection. Detection of negative-sense strand viral RNA and isolation of infectious virus derived from these convalescent mice by blinded passage in Vero cells confirmed long-term persistence of replicating ZIKV in CNS of convalescent mice. Although the infection appears to persist in defined reservoirs within CNS, the resulting inflammation could increase the risk of neurodegenerative disorders. This raises concern regarding possible long-term effects in asymptomatic children exposed to the virus and suggests that long-term neurological and behavioral monitoring as well as anti-viral treatment to clear virus from the CNS may be useful in patients exposed to ZIKV at an early age.

Dietary Supplementation of a Live Yeast Product on Dairy Sheep Milk Performance, Oxidative and Immune Status in Peripartum Period.

This study evaluated the dietary administration of Saccharomyces cerevisiae live yeast on milk performance and composition, oxidative status of both blood plasma and milk, and gene expression related to the immune system of lactating ewes during the peripartum period. Chios ewes were fed either a basal diet (BD) (Control, n = 51) or the BD supplemented with 2 g of a live yeast product/animal (ActiSaf, n = 53) from 6 weeks prepartum to 6 weeks postpartum. Fatty acid profile, oxidative, and immune status were assessed in eight ewes per treatment at 3 and 6 weeks postpartum. The β-hydroxybutyric acid concentration in blood of ActiSaf fed ewes was significantly lower in both pre- and postpartum periods. A numerical increase was found for the milk yield, fat 6% corrected milk (Fat corrected milk (FCM6%)), and energy corrected milk yield (ECM) in ActiSaf fed ewes, while daily milk fat production tended to increase. The proportions of C15:0, C16:1, C18:2n6t, and C18:3n3 fatty acids were increased in milk of ActiSaf fed ewes, while C18:0 was decreased. Glutathione reductase in blood plasma was increased (p = 0.004) in ActiSaf fed ewes, while total antioxidant capacity measured by 2,2′-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) method was decreased (p < 0.001). Higher ABTS values were found in the milk of the treated group. The relative transcript levels of CCL5, CXCL16, and IL8 were suppressed, while that of IL1B tended to decrease (p = 0.087) in monocytes of ActiSaf fed ewes. In conclusion, the dietary supplementation of ewes with S. cerevisiae, improved the energy utilization and tended to enhance milk performance with simultaneous suppression on mRNA levels of pro-inflammatory genes during the peripartum period.

The human glomerular endothelial cells are potent pro-inflammatory contributors in an in vitro model of lupus nephritis

Juvenile-onset lupus nephritis (LN) affects up to 80% of juvenile-onset systemic lupus erythematosus patients (JSLE). As the exact role of human renal glomerular endothelial cells (GEnCs) in LN has not been fully elucidated, the aim of this study was to investigate their involvement in LN. Conditionally immortalised human GEnCs (ciGEnCs) were treated with pro-inflammatory cytokines known to be involved in LN pathogenesis and also with LPS. Secretion and surface expression of pro-inflammatory proteins was quantified via ELISA and flow cytometry. NF-κΒ and STAT-1 activation was investigated via immunofluorescence. Serum samples from JSLE patients and from healthy controls were used to treat ciGEnCs to determine via qRT-PCR potential changes in the mRNA levels of pro-inflammatory genes. Our results identified TNF-α, IL-1β, IL-13, IFN-γ and LPS as robust in vitro stimuli of ciGEnCs. Each of them led to significantly increased production of different pro-inflammatory proteins, including; IL-6, IL-10, MCP-1, sVCAM-1, MIP-1α, IP-10, GM-CSF, M-CSF, TNF-α, IFN-γ, VCAM-1, ICAM-1, PD-L1 and ICOS-L. TNF-α and IL-1β were shown to activate NF-κB, whilst IFN-γ activated STAT-1. JSLE patient serum promoted IL-6 and IL-1β mRNA expression. In conclusion, our in vitro model provides evidence that human GEnCs play a pivotal role in LN-associated inflammatory process.

Evaluation of development, locomotor behavior, oxidative stress, immune responses and apoptosis in developing zebrafish (Danio rerio) exposed to TBECH (tetrabromoethylcyclohexane)

Tetrabromoethylcyclohexane (TBECH), as one emerging brominated flame retardants, is ubiquitous in the environment, including water and aquatic organisms. TBECH was found to exhibit endocrine-disrupting effects in different models, whereas a survey of comprehensive toxic effects of TBECH on zebrafish is limited. In the present study, zebrafish (Danio rerio) were waterborne exposed continuously to TBECH from embryonic stage (3 h post-fertilization (hpf)) to the time when the respective parameters were evaluated. Exposure to TBECH reduced hatchability of zebrafish embryos at 72 and 96 hpf, diminished heart rate of zebrafish larvae at 48 hpf, and increased malformation in zebrafish larvae at 96 hpf. In addition, exposure to TBECH diminished free swimming distance both in the light and under a photoperiod of 10 min light/10 min dark cycles in zebrafish larvae at 6 days post-fertilization (dpf). Moreover, exposure to TBECH elevated activities of superoxide dismutase (SOD) and catalase (CAT), malondialdehyde (MDA) content, whereas it reduced glutathione (GSH) content, in zebrafish larvae at 6 dpf. Accordingly, RT-qPCR analysis demonstrated that TBECH exposure increased the mRNA levels of sod1, sod2, cat, and gpx1 in zebrafish larvae at 6 dpf. With respect to the immune aspect, the mRNA levels of pro-inflammatory genes, including il-1b, il-6, il-8, and tnfa, in larval zebrafish at 6 dpf were increased by exposure to TBECH, while pretreatment with TBECH inhibited 24 h of exposure to LPS-stimulated elevation in the mRNA levels of the abovementioned four pro-inflammatory genes in zebrafish larvae at 6 dpf. Furthermore, TBECH treatment increased caspase-3 enzyme activities and regulated apoptosis-related genes in larval zebrafish at 6 dpf. Taken together, the data obtained in this study demonstrated that TBECH caused developmental and locomotor behavioral toxicity, immunotoxicity, oxidative stress and proapoptotic effects in early life zebrafish. The present study will help to understand the comprehensive toxicity of TBECH in zebrafish.

Effects of dietary arginine on antioxidant status and immunity involved in AMPK-NO signaling pathway in juvenile blunt snout bream

The present study assessed the effects of dietary arginine on antioxidant status and immunity involved in AMPK-NO signaling pathway in juvenile blunt snout bream. Fish were fed six practical diets with graded arginine levels ranging from 0.87% to 2.70% for 8 weeks. The results showed that compared with the control group (0.87% dietary arginine level), significantly higher mRNA levels of adenosine monophosphate activated protein kinase (AMPK) and nitric oxide synthetase (NOS), activities of total nitric oxide synthetase (T-NOS) and nitric oxide synthetase (iNOS), and plasma nitric oxide (NO) contents were observed in fish fed with 1.62%–2.70% dietary arginine levels. Significantly higher levels of NOS and iNOS were observed in fish fed with 1.62%–2.70% dietary arginine levels in enzyme-linked immune sorbent assay. At dietary arginine levels of 1.22%–2.70%, the mRNA levels of iNOS were significantly improved. Dietary arginine also significantly influenced plasma interleukin 8 (IL-8) and tumour necrosis factor-α (TNF-α) contents. Furthermore, dietary arginine significantly affected the activity and mRNA level of glutathione peroxidase (GPx), the mRNA levels of pro-inflammatory factor including IL-8 and TNF-α and plasma malondialdehyde (MDA) content. However, total superoxide dismutase (T-SOD) activity, plasma complement component 3 (C3) content, plasma immunoglobulin M (IgM) content, plasma interleukin 1β (IL-1β) content and the mRNA levels of copperzinc superoxide dismutase (Cu/Zn-SOD), manganese superoxide dismutase (Mn-SOD) and IL-1β were not significantly affected by dietary arginine. After Aeromonas hydrophila challenge, the death rate was significantly lowered in fish fed with 1.62%–1.96% dietary arginine levels. Furthermore, the mRNA levels of AMPK, NOS and iNOS, plasma NO content and the activities of T-NOS and iNOS showed an upward trend with increasing dietary arginine levels. Significantly higher levels of NOS and iNOS were observed in fish fed with 1.62%–2.70% dietary arginine levels in enzyme-linked immune sorbent assay. At dietary arginine levels of 1.96%–2.31%, T-SOD activities were significantly improved. Significantly higher GPx activities were observed in fish fed with 1.22%–2.70% dietary arginine levels. At dietary arginine levels of 1.22%–2.31%, the plasma TNF-α and IL-8 contents were significantly decreased. Significantly lower plasma IL-1β contents were observed in fish fed 1.62%–1.96% dietary arginine levels. Dietary arginine significantly influenced the mRNA levels of antioxidant and pro-inflammatory genes including Cu/Zn-SOD, Mn-SOD, GPx, IL-8, TNF-α and IL-1β. Significantly higher plasma C3 contents and significantly lower plasma MDA contents were observed in fish fed with 1.62%–1.96% arginine levels. Furthermore, plasma IgM contents were significantly improved at dietary arginine levels of 1.62%–2.31%. However, high dietary arginine group (2.70%) significantly improved the mRNA levels of pro-inflammatory genes including IL-8, TNF-α and IL-1β and plasma MDA, IL-8, TNF-α and IL-1β contents as compared with optimal dietary arginine levels (1.62% and 1.96%). The present results indicate that optimal arginine level (1.62% and 1.96%) could improve antioxidant capacity, immune response and weaken tissues inflammatory involved in arginine-AMPK-NO signaling pathway, while high arginine level resulted in excessive NO production, leading to increase oxidative stress damage and inflammatory response in juvenile blunt snout bream.

Anti-inflammatory activity of Khayandirobilide A from Khaya senegalensis via NF-κB, AP-1 and p38 MAPK/Nrf2/HO-1 signaling pathways in lipopolysaccharide-stimulated RAW 264.7 and BV-2 cells

BackgroundImmunocytes-involved inflammation is considered to modulate the damage in various diseases. Herein, novel therapeutics suppressing over-activation of immunocytes could prove an effective strategy to prevent inflammation-related diseases. PurposeThe objective of this study is to evaluate the anti-inflammatory activity of Khayandirobilide A (KLA), a new andirobin-type limonoid with modified furan ring isolated from the Khaya senegalensis (Desr.) A. Juss., and to explore its potential underlying mechanisms in LPS-stimulated inflammatory models. MethodsThe structure of KLA was elucidated on the basis of 1D- and 2D-NMR spectroscopic data as well as HR-ESI-MS. As for its anti-inflammatory effect, the production of pro-inflammatory mediators and cytokines in LPS-stimulated RAW 264.7 and BV-2 cells were measured by Griess reagent, ELISA and qRT-PCR. The relevant proteins including nuclear factor κB (NF-κB), p-AKT, p-p38 and Nrf2/HO-1 were investigated by western blot. Nuclear localisations of NF-κB, activator protein-1 (AP-1) and Nrf2 were also examined by western blot and immunofluorescence. ResultsKLA could inhibit the production of LPS-induced NO with IC50 values of 5.04 ± 0.14 µM and 4.97 ± 0.5 µM in RAW 264.7 and BV-2 cells, respectively. KLA also attenuated interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels. Further mechanistic studies demonstrated the activation of NF-κB and AP-1 were reduced by KLA. Moreover, KLA elevated expression of heme oxygenase-1(HO-1) via inducing Keap1 autophagic degradation and promoting Nrf2 nuclear translocation. Despite KLA induced the phosphorylation of mitogen-activated protein kinases (MAPKs) family, inhibiting the phosphorylation of p38 by its specific inhibitor SB203580 attenuated the degradation of KLA-induced Keap1, and then reduced KLA-induced Nrf2 nuclear translocation and HO-1 expression. Furthermore, SB203580, Brusatol (a Nrf2 specific inhibitor) and ZnPP (a HO-1 specific inhibitor) could partly reverse the suppressive effects of KLA on LPS-induced NO production and mRNA levels of pro-inflammatory genes. ConclusionThese data displayed that KLA possessed anti-inflammatory activity, which was attributed to inhibit the release of LPS-stimulated inflammatory mediators via suppressing the activation of NF-κB, AP-1, and upregulating the induction of p38 MAPK/Nrf2-mediated HO-1.

Urolithins Attenuate LPS-Induced Neuroinflammation in BV2Microglia via MAPK, Akt, and NF-κB Signaling Pathways.

Emerging data suggest that urolithins, gut microbiota metabolites of ellagitannins, contribute toward multiple health benefits attributed to ellagitannin-rich foods, including walnuts, red raspberry, strawberry, and pomegranate. However, there is limited data on whether the potential neuroprotective effects of these ellagitannin-rich foods are mediated by urolithins. Herein, we evaluated the potential mechanisms of antineuroinflammatory effects of urolithins (urolithins A, B, and C; 8-methyl-O-urolithin A; and 8,9-dimethyl-O-urolithin C) in BV2 murine microglia in vitro. Nitrite analysis and qRT-PCR suggested that urolithins A and B reduced NO levels and suppressed mRNA levels of pro-inflammatory genes of TNF-α, IL-6, IL-1β, iNOS, and COX-2 in LPS-treated microglia. Western blot revealed that urolithins A and B decreased phosphorylation levels of Erk1/2, p38 MAPK, and Akt, prevented IκB-α phosphorylation and degradation, and inhibited NF-κB p65 subunit phosphorylation and nuclear translocation in LPS-stimulated microglia. Our results indicated that urolithins A and B attenuated LPS-induced inflammation in BV2 microglia, which may be mediated by inhibiting NF-κB, MAPKs (p38 and Erk1/2), and Akt signaling pathway activation. The antineuroinflammatory activities of urolithins support their role in the potential neuroprotective effects reported for ellagitannin-rich foods warranting further in vivo studies on these ellagitannin gut microbial derived metabolites.

Nuclear factor kappa-B- and activator protein-1-mediated immunostimulatory activity of compound K in monocytes and macrophages

BackgroundCompound K (CK) is a bioactive derivative of ginsenoside Rb1 in Panax ginseng (Korean ginseng). Its biological and pharmacological activities have been studied in various disease conditions, although its immunomodulatory role in innate immunity mediated by monocytes/macrophages has been poorly understood. In this study, we aimed to elucidate the regulatory role of CK on cellular events mediated by monocytes and macrophages in innate immune responses. MethodsThe immunomodulatory role of CK was explored by various immunoassays including cell-cell adhesion, fibronectin adhesion, cell migration, phagocytic uptake, costimulatory molecules, reactive oxygen species production, luciferase activity, and by the measurement of mRNA levels of proinflammatory genes. ResultsCompound K induced cell cluster formation through cell-cell adhesion, cell migration, and phagocytic activity, but it suppressed cell-tissue interactions in U937 and RAW264.7 cells. Compound K also upregulated the surface expression of the cell adhesion molecule cluster of differentiation (CD) 43 (CD43) and costimulatory molecules CD69, CD80, and CD86, but it downregulated the expression of monocyte differentiation marker CD82 in RAW264.7 cells. Moreover, CK induced the release of reactive oxygen species and induced messenger RNA expression of proinflammatory genes, inducible nitric oxide synthase, and tumor necrosis factor-alpha by enhancing the nuclear translocation and transcriptional activities of nuclear factor kappa-B and activator protein-1. ConclusionOur results suggest that CK has an immunomodulatory role in innate immune responses through regulating various cellular events mediated by monocytes and macrophages.

α-Linolenic acid (ALA) is an anti-inflammatory agent in inflammatory bowel disease

Studies suggest that consumption of omega-3 (n-3) polyunsaturated fatty acids (PUFA) plays a protective role in inflammatory bowel disease; however, the use of plant-derived oils rich in α-linolenic acid (ALA) has not been widely investigated. The aims of this study were to test the effects of two different sources of (n-3) PUFA, fish and plant-derived oils, in two animal models of experimental colitis and to determine whether the (n-3) PUFA-enriched diets could ameliorate the inflammatory status. Rats were fed diets rich in corn, fish or sage oil with or without vitamin A supplementation for 3weeks then colitis was induced by adding dextran sodium sulfate to the drinking water or by injecting 2,4,6-trinitrobenzene sulfonic acid. We show that colitic rats fed the sage oil diets had a lower inflammatory response, improved histological repair and had less necrotic damage in the mucosa when compared to the corn and fish oil groups. Colonic damage and myeloperoxidase activity were significantly lower. Colonic mRNA levels of pro-inflammatory genes including interleukin IL-6, cyclooxygenase 2 and tumor necrosis factor α were markedly down-regulated in rats fed fish and sage oils compared to control. These results were supported by experiments in the human colonic epithelial cell line Caco-2, where ALA supplementation was shown to be effective in inhibiting inflammation induced by IL-1β by down-regulating mRNA levels of pro-inflammatory genes including IL-8, COX2 and inducible nitric oxide synthase. Taken together, these results suggest that plant-derived oil rich in ALA could ameliorate the inflammatory damage in colitis.

Neutrophils Play a Crucial Role in the Early Stage of Nonalcoholic Steatohepatitis via Neutrophil Elastase in Mice.

Neutrophils infiltration in liver is one of the typical histological characteristics of nonalcoholic steatohepatitis (NASH) in both animal models and human subjects. This study was aimed to investigate the role of neutrophils in the process of NASH and its underling mechanisms. C57BL/6J mice were fed with either standard chow (SC) or methionine/choline-deficient (MCD) diet for 1, 2, 4, 8weeks, respectively. C57BL/6J APOE(-/-) mice were fed with SC or high-fat high-cholesterol (HFHC) diet. Anti-Ly6G antibody was employed to deplete neutrophils and sivelestat was used to inhibit neutrophil elastase (NE). MCD-diet-receiving mice with neutrophil depletion had much lower serum ALT activity, liver inflammation, and mRNA levels of proinflammatory genes in the early stage of NASH (1 and 2weeks) when compared to non-neutrophil-depleted mice. NE inhibitor sivelestat could recapitulate the effects of neutrophil depletion in APOE(-/-) mice fed with HFHC diet. As the disease progressed (4 and 8weeks), neutrophil depletion did not lower serum ALT levels and liver lesions due to activation of Kupffer cells. Finally, we found neutrophils also affected anti-inflammation cytokine interleukin-1 receptor antagonist mRNA expression. Neutrophils play a crucial role in the early stage of NASH via NE.

Effects of polymer-coated metal oxide nanoparticles on goldfish (Carassius auratus L.) neutrophil viability and function

Exposure effects from polyacrylic acid (PAA) metal-oxide nanoparticles (TiO2, CeO2, Fe2O3, ZnO) on fish neutrophil viability and effector functions (degranulation, respiratory burst, inflammatory gene expression) were investigated using primary kidney goldfish (Carassius auratus L.) neutrophils as a model. Several studies have reported cytotoxic effects of NPs but there are limited reports on their potential to perturb the innate immune system of aquatic organisms. PAA-TiO2 significantly decreased neutrophil viability in a time and dose-dependent manner at all measured time points (0–48 h) and concentrations (0–200 µg/mL). Maximum viability decreased by (mean ± SEM): 67.1 ± 3.3%, 78.4 ± 4.2% and 74.9 ± 5.0% when exposed to 50, 100 and 200 µg/mL for 48 h, respectively. PAA-ZnO also significantly decreased neutrophil viability but only at 48 h exposures at higher concentrations. Neutrophil degranulation increased by approximately 3% after 30 min and by 8% after 4 h when exposed to sublethal doses (10 µg/mL) of PAA-CeO2 or PAA-Fe2O3. All PAA-NPs induced an increase in neutrophil respiratory burst when exposed to 10 µg/mL for 30 and 60 min, however, PAA-Fe2O3 was the only NP where the response was significant. Lastly, NPs altered the expression of a number of pro-inflammatory and immune genes, where PAA-TiO2 most significantly increased the mRNA levels of pro-inflammatory genes (il-1b, ifng) in neutrophils by 3 and 2.5 times, respectively. Together, these data demonstrate that goldfish neutrophils can be negatively affected from exposures to PAA-coated NPs and are functionally responsive to specific core-material properties at sublethal doses. These changes could perturb the innate response and affect the ability of fish to respond to pathogens.

The analysis of goldfish (Carassius auratus L.) innate immune responses after acute and subchronic exposures to oil sands process-affected water.

We examined the immunotoxic effects of acute and subchronic exposures of goldfish to aged, fresh, and ozonated oil sands process-affected water (OSPW) using a flow-through exposure apparatus. We measured the expression of proinflammatory cytokine genes, the antimicrobial responses of primary macrophages isolated from OSPW-exposed fish, and the ability of the goldfish to control infection with a protozoan parasite, Trypanosoma carassii. After acute (1 week) exposure to aged OSPW, we observed upregulation in the expression of interferon gamma (IFN-γ), tumor necrosis factor alpha-2 (TNF-α2) in the kidney and spleen but not in gills of the fish. After subchronic (12 weeks) exposure to aged OSPW, we observed significant increases in mRNA levels of proinflammatory genes in the gill (IFN-γ, interleukin-1 beta 1 [IL1-β1], TNF-α2), kidney (IL1-β1, TNF-α2), and spleen (IL1-β1). An upregulation of immune gene expression in the gill and kidney (IFN-γ, IL1-β1, TNF-α2) and spleen (IL1-β1, TNF-α2) was observed after acute exposure of fish to diluted fresh OSPW. Following subchronic exposure to diluted fresh OSPW, we observed high mRNA levels of IL1-β1 in all tissues examined. However, there were significant decreases in the mRNA levels of IFN-γ and TNF-α2 in the kidney and spleen and gill and spleen (IL-12p35 and IL-12p40) of exposed fish. There were no changes in the expression of anti-inflammatory cytokine IL-10 after both acute and subchronic exposures to diluted fresh OSPW. In fish exposed to ozonated fresh OSPW, immune gene expression was similar to nonexposed control fish in all organs examined, with exception of IL1-β1. The ability of primary kidney macrophages to generate reactive oxygen and nitrogen intermediates was significantly reduced in fish exposed to fresh OSPW. The enhanced proinflammatory response after acute exposure to diluted fresh OSPW was confirmed by the parasite challenge experiments, where OSPW-exposed fish controlled the infection better than nonexposed fish.

S1729 Colitis-Associated Cancer in Mice Lacking the RNA-Binding Protein APOBEC-1

The bile salt nuclear receptor Farnesoid X Receptor (FXR) was recently implicated in intestinal antibacterial defense and barrier function. We aimed to study its role in pathogenesis of inflammatory bowel diseasE. colitis was induced in Wild Type (WT) and FXR knock-out (ko) mice (n=8 to 10 for each group) by Dextran Sodium Sulphate (DSS: 2.5% in drinking water, 10 days) with or without synthetic FXR ligand 6-Ethyl Chenodeoxycholic Acid (6ECDCA: 5 mg/kg/day, 13 days, starting 3 days before DSS). Colitis symptoms were checked daily and intestinal permeability (FITC-dextran assay), bile salt composition (HPLC), histology and colonic inflammatory gene expression (Q-PCR) determined. mRNA expression of FXR and target genes was determined in IBD patient biopsies. Underlying mechanisms were explored in complementary In Vitro experiments. 6ECDCA-treated WT but not FXR ko mice were protected from DSS-induced colitis, as shown by highly significant reduction of body weight loss, rectal bleeding, colonic shortening, normalization of intestinal permeability, 49% reduction in blinded histological score and 55% reduction in goblet cell loss. Only in 6ECDCA-treated WT mice, mRNA levels of pro-inflammatory genes (IL-1β, IL-6, IL10 and MCP-1) were strongly down-regulated while antibacterial defense gene iNOS was upregulated. 6ECDCA was enriched in bile of both WT and FXR ko mice (9.8% and 5.3% of total bile salts, respectively). However intestinal expression of FXR target genes FGF15 and SHP was increased 4.5and 19-fold with 6ECDCA treatment only in WT. In patients with quiescent Crohn colitis (n=17), mRNA expression of FXR and SHP was significantly altered compared to patients with ulcerative colitis (n=16) or healthy controls (n=17). In differentiated CaCo2 cells grown on trans-well plates, FXR activation by GW4064 prevented DSS-dependent loss of integrity of the monolayer. In differentiated HT29 cells, TNFαinduced 20-fold increase of IL-1β expression was abolished by GW4064-dependent FXR activation. In reporter assays, the FXR agonist GW4064 prevented TNFα-induced NF-κB activity in HEK293 cells transfected with WT FXR, but no effect was achieved with FXR mutant W469A (defective in Ligand Binding Domain), indicating FXR-mediated inhibition of NF-κB signalling. In conclusion, FXR activation protects against experimental murine colitis, supposedly by preserving the intestinal barrier and inhibitingNF-κB activity. Currently available potent synthetic FXR agonists may offer new therapeutic strategies for inflammatory bowel disease.

S1728 Intestinal Bile Salt Nuclear Receptor FXR Protects From Inflammatory Bowel Disease: Potential Therapeutic Implications

The bile salt nuclear receptor Farnesoid X Receptor (FXR) was recently implicated in intestinal antibacterial defense and barrier function. We aimed to study its role in pathogenesis of inflammatory bowel diseasE. colitis was induced in Wild Type (WT) and FXR knock-out (ko) mice (n=8 to 10 for each group) by Dextran Sodium Sulphate (DSS: 2.5% in drinking water, 10 days) with or without synthetic FXR ligand 6-Ethyl Chenodeoxycholic Acid (6ECDCA: 5 mg/kg/day, 13 days, starting 3 days before DSS). Colitis symptoms were checked daily and intestinal permeability (FITC-dextran assay), bile salt composition (HPLC), histology and colonic inflammatory gene expression (Q-PCR) determined. mRNA expression of FXR and target genes was determined in IBD patient biopsies. Underlying mechanisms were explored in complementary In Vitro experiments. 6ECDCA-treated WT but not FXR ko mice were protected from DSS-induced colitis, as shown by highly significant reduction of body weight loss, rectal bleeding, colonic shortening, normalization of intestinal permeability, 49% reduction in blinded histological score and 55% reduction in goblet cell loss. Only in 6ECDCA-treated WT mice, mRNA levels of pro-inflammatory genes (IL-1β, IL-6, IL10 and MCP-1) were strongly down-regulated while antibacterial defense gene iNOS was upregulated. 6ECDCA was enriched in bile of both WT and FXR ko mice (9.8% and 5.3% of total bile salts, respectively). However intestinal expression of FXR target genes FGF15 and SHP was increased 4.5and 19-fold with 6ECDCA treatment only in WT. In patients with quiescent Crohn colitis (n=17), mRNA expression of FXR and SHP was significantly altered compared to patients with ulcerative colitis (n=16) or healthy controls (n=17). In differentiated CaCo2 cells grown on trans-well plates, FXR activation by GW4064 prevented DSS-dependent loss of integrity of the monolayer. In differentiated HT29 cells, TNFαinduced 20-fold increase of IL-1β expression was abolished by GW4064-dependent FXR activation. In reporter assays, the FXR agonist GW4064 prevented TNFα-induced NF-κB activity in HEK293 cells transfected with WT FXR, but no effect was achieved with FXR mutant W469A (defective in Ligand Binding Domain), indicating FXR-mediated inhibition of NF-κB signalling. In conclusion, FXR activation protects against experimental murine colitis, supposedly by preserving the intestinal barrier and inhibitingNF-κB activity. Currently available potent synthetic FXR agonists may offer new therapeutic strategies for inflammatory bowel disease.

Akt Cys-310-targeted Inhibition by Hydroxylated Benzene Derivatives Is Tightly Linked to Their Immunosuppressive Effects

The hydroxylated benzene metabolite hydroquinone (HQ) is mainly generated from benzene, an important industrial chemical, and is also a common dietary component. Although numerous reports have addressed the tumorigenesis-inducing effects of HQ, few papers have explored its molecular regulatory mechanism in immunological responses. In this study we characterized Akt (protein kinase B)-targeted regulation by HQ and its derivatives, in suppressing inflammatory responses using cellular, molecular, biochemical, and immunopharmacological approaches. HQ down-regulated inflammatory responses such as NO production, surface levels of pattern recognition receptors, and cytokine gene expression with IC(50) values that ranged from 5 to 10 microm. HQ inhibition was mediated by blocking NF-kappaB activation via suppression of its translocation pathway, which is composed of Akt, I kappaB alpha kinase beta, and I kappaB alpha. Of the targets in this pathway, HQ directly targeted and bound to the sulfhydryl group of Cys-310 of Akt and sequentially interrupted the phosphorylation of both Thr-308 and Ser-473 by mediation of beta-mercaptoethanol, according to the liquid chromatography/mass spectroscopy analysis of the interaction of HQ with an Akt-derived peptide. Therefore, our data suggest that Akt and its target site Cys-310 can be considered as a prime molecular target of HQ-mediated immunosuppression and for novel anti-Akt-targeted immunosuppressive drugs.

A Selective p38α Mitogen-Activated Protein Kinase Inhibitor Reverses Cartilage and Bone Destruction in Mice with Collagen-Induced Arthritis

Destruction of cartilage and bone is a poorly managed hallmark of human rheumatoid arthritis (RA). p38 Mitogen-activated protein kinase (MAPK) has been shown to regulate key proinflammatory pathways in RA, including tumor necrosis factor alpha, interleukin (IL)-1beta, and cyclooxygenase-2, as well as the process of osteoclast differentiation. Therefore, we evaluated whether a p38alpha MAPK inhibitor, indole-5-carboxamide (SD-282), could modulate cartilage and bone destruction in a mouse model of RA induced with bovine type II collagen [collagen-induced arthritis (CIA)]. In mice with early disease, SD-282 treatment significantly improved clinical severity scores, reduced bone and cartilage loss, and reduced mRNA levels of proinflammatory genes in paw tissue, including IL-1beta, IL-6, and cyclooxygenase-2. Notably, SD-282 treatment of mice with advanced disease resulted in significant improvement in clinical severity scoring and paw swelling, a reversal in bone and cartilage destruction as assessed by histology, bone volume fraction and thickness, and three-dimensional image analysis. These changes were accompanied by reduced osteoclast number and lowered levels of serum cartilage oligomeric matrix protein, a marker of cartilage breakdown. Thus, in a model of experimental arthritis associated with significant osteolysis, p38alpha MAPK inhibition not only attenuates disease progression but also reverses cartilage and bone destruction in mice with advanced CIA disease.