Effect of resolvin D5 on T cell differentiation and osteoclastogenesis analyzed by lipid mediator profiling in the experimental arthritis.

Resolvins, are specialized pro-resolving mediators (SPMs) derived from n-3 polyunsaturated fatty acids. They contribute actively to the resolution of inflammation, but little is known concerning their role in chronic inflammation, such as in rheumatoid arthritis (RA). Here, we performed lipid mediator (LM) profiling in tissues from the paws of SKG arthritic mice using lipid chromatography (LC)/mass spectrometry (MS)/MS-based LM metabololipidomics. We found elevated levels of SPMs including resolvin D5 (RvD5) in these tissues. Moreover, RvD5 levels were significantly correlated with arthritis disease activity. From experiments to assess the role of RvD5 in the pathology of RA, we concluded that RvD5 suppressed Th17 cell differentiation and facilitated regulatory T cell differentiation, as well as inhibiting CD4+ T cell proliferation. Furthermore, RvD5 attenuated osteoclast differentiation and interfered with osteoclastogenesis. Targeting the resolution of inflammation could be promising as a novel treatment for RA.

Caspofungin suppresses zymosan-induced cytokine and chemokine release in THP-1 cells: possible involvement of the spleen tyrosine kinase pathway.

Systemic inflammatory response syndrome and sepsis are considered to contribute to hypercytokinemia in both patients with severe infection and immunocompromised condition. Past research has demonstrated that antibiotics and antifungals not only have antimicrobial efficacy but also affect the immune system. We previously examined whether immune cells were modulated by antibiotics such as tetracyclines or macrolides. The modulation of lipopolysaccharide-stimulated cells by those agents was elucidated. However, few reports about the modulation of the immune system by antifungal agents were found. In this study, the production of pro-inflammatory cytokines and chemokines and signaling pathways involved were investigated in zymosan-activated THP-1 cells. The effects were examined using antifungal agents such as echinocandin including caspofungin (CAS) and micafungin. Pro-inflammatory cytokine and chemokine levels were determined using enzyme-linked immunosorbent assay. Protein phosphorylation was evaluated by western blot analysis. CAS significantly decreased zymosan-induced pro-inflammatory cytokine and chemokine release in THP-1 cells. CAS (30 µg/mL) also downregulated tumor necrosis factor alpha levels, as shown by enzyme-linked immunosorbent assay. In western blot analysis, inhibitor of nuclear factor-kappa-B alpha, p38, c-Jun N-terminal kinase, extracellular signal-regulated kinase, and nuclear factor of activated T-cells phosphorylation and activation of caspase-1 and spleen tyrosine kinase (Syk) were downregulated. The major underlying mechanism of pro-inflammatory cytokine and chemokine suppression by CAS is to inhibit activation of Syk and its downstream signaling molecules. Based on the results, it can be concluded that CAS activity possibly involves Syk signaling pathways and has potential to prevent hypercytokinemia in fungal sepsis.

The citrus flavanone naringenin attenuates zymosan-induced mouse joint inflammation: induction of Nrf2 expression in recruited CD45+ hematopoietic cells.

BACKGROUND: Naringenin is a biologically active analgesic, anti-inflammatory, and antioxidant flavonoid. Naringenin targets in inflammation-induced articular pain remain poorly explored. METHODS: The present study investigated the cellular and molecular mechanisms involved in the analgesic/anti-inflammatory effects of naringenin in zymosan-induced arthritis. Mice were pre-treated orally with naringenin (16.7-150 mg/kg), followed by intra-articular injection of zymosan. Articular mechanical hyperalgesia and oedema, leucocyte recruitment to synovial cavity, histopathology, expression/production of pro- and anti-inflammatory mediators and NFκB activation, inflammasome component expression, and oxidative stress were evaluated. RESULTS: Naringenin inhibited articular pain and oedema in a dose-dependent manner. The dose of 50 mg/kg inhibited leucocyte recruitment, histopathological alterations, NFκB activation, and NFκB-dependent pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-33), and preproET-1 mRNA expression, but increased anti-inflammatory IL-10. Naringenin also inhibited inflammasome upregulation (reduced Nlrp3, ASC, caspase-1, and pro-IL-1ß mRNA expression) and oxidative stress (reduced gp91phox mRNA expression and superoxide anion production, increased GSH levels, induced Nrf2 protein in CD45+ hematopoietic recruited cells, and induced Nrf2 and HO-1 mRNA expression). CONCLUSIONS: Naringenin presents analgesic and anti-inflammatory effects in zymosan-induced arthritis by targeting its main physiopathological mechanisms. These data highlight this flavonoid as an interesting therapeutic compound to treat joint inflammation, deserving additional pre-clinical and clinical studies.

The phytosphingosine-CD300b interaction promotes zymosan-induced, nitric oxide-dependent neutrophil recruitment.

Zymosan is a glucan that is a component of the yeast cell wall. Here, we determined the mechanisms underlying the zymosan-induced accumulation of neutrophils in mice. Loss of the receptor CD300b reduced the number of neutrophils recruited to dorsal air pouches in response to zymosan, but not in response to lipopolysaccharide (LPS), a bacterial membrane component recognized by Toll-like receptor 4 (TLR4). An inhibitor of nitric oxide (NO) synthesis reduced the number of neutrophils in the zymosan-treated air pouches of wild-type mice to an amount comparable to that in CD300b-/- mice. Treatment with clodronate liposomes decreased the number of NO-producing, CD300b+ inflammatory dendritic cells (DCs) in wild-type mice, thus decreasing NO production and neutrophil recruitment. Similarly, CD300b deficiency decreased the NO-dependent recruitment of neutrophils to zymosan-treated joint cavities, thus ameliorating subsequent arthritis. We identified phytosphingosine, a lipid component of zymosan, as a potential ligand of CD300b. Phytosphingosine stimulated NO production in inflammatory DCs and promoted neutrophil recruitment in a CD300b-dependent manner. Together, these results suggest that the phytosphingosine-CD300b interaction promotes zymosan-dependent neutrophil accumulation by inducing NO production by inflammatory DCs and that CD300b may contribute to antifungal immunity.

Extremely high-frequency electromagnetic radiation enhances neutrophil response to particulate agonists.

The growing use of extremely high-frequency electromagnetic radiation (EHF EMR) in information and communication technology and in biomedical applications has raised concerns regarding the potential biological impact of millimeter waves (MMWs). Here, we elucidated the effects of MMW radiation on neutrophil activation induced by opsonized zymosan or E. coli in whole blood ex vivo. After agonist addition to blood, two samples were prepared. A control sample was incubated at ambient conditions without any treatment, and a test sample was exposed to EHF EMR (32.9-39.6 GHz, 100 W/m2 ). We used methods that allowed us to assess the functional status of neutrophils immediately after exposure: oxidant production levels were measured by luminol-dependent chemiluminescence, and morphofunctional changes to neutrophils were observed in blood smears. Results revealed that the response of neutrophils to both agonists was intensified if blood was exposed to MMW radiation for 15 min. Neutrophils were intact in both the control and irradiated samples if no agonist was added to blood before incubation. Similarly, exposing suspensions of isolated neutrophils in plasma to MMW radiation enhanced cell response to both zymosan and E. coli. Heating blood samples was shown to be the primary mechanism underlying enhanced EHF EMR-induced oxidant production by neutrophils in response to particulate agonists. Bioelectromagnetics. 39:144-155, 2018. © 2017 Wiley Periodicals, Inc.

A new depsidone derivative from the leaves of Garcinia polyantha.

One new depsidone, polyanthadepsidone A (1), together with four known compounds were isolated from the dichloromethane extract of the leaves of Garcinia polyantha. The structures of all compounds were determined by comprehensive analyses of their 1D and 2D NMR and EI mass spectral data. All the isolates exhibited suppressive effect on phagocytosis response upon activation with serum opsonised zymosan in the IC50 range of 4.5-23.80 µM, tested in vitro for oxidative burst studies of whole blood.

Expression and role of gap junction protein connexin43 in immune challenge-induced extracellular ATP release in Japanese flounder (Paralichthys olivaceus).

Connexin43 (Cx43) is the best characterized gap junction protein that allows the direct exchange of signaling molecules during cell-to-cell communications. The immunological functions and ATP permeable properties of Cx43 have been insensitively examined in mammals. The similar biological significance of Cx43 in lower vertebrates, however, is not yet understood. In the present study we identified and characterized a Cx43 ortholog (termed PoCx43) from Japanese flounder (Paralichthys olivaceus) and investigated its role in immune challenge-induced extracellular ATP release. PoCx43 mRNA transcripts are widely distributed in all tested normal tissues and cells with predominant expression in the brain, and are significantly up-regulated by LPS, poly(I:C) and zymosan challenges and Edwardsiella tarda infections as well, suggesting that PoCx43 expression was modulated by the inflammatory stresses. In addition, cyclic AMP (cAMP), an essential second messenger, also plays an important role in regulating PoCx43 gene expression, by which the PoCx43-mediated gap junctional communication may be regulated. Furthermore, overexpression of PoCx43 in Japanese flounder FG-9307 cells significantly potentiates the LPS- and poly(I:C)-induced extracellular ATP release and this enhanced ATP release was attenuated by pre-incubation with Cx43 inhibitor carbenoxolone. In a complementary experiment, down-regulation of PoCx43 endogenous expression in FG-9307 cells with small interfering RNA also significantly reduced the PAMP-induced extracellular ATP release, suggesting that PoCx43 is an important ATP release conduit under the immune challenge conditions. Finally, we showed that extracellular ATP stimulation led to an increased PoCx43 expression which probably provides a feedback mechanism in regulating PoCx43 expression at the transcriptional level. These findings suggest that PoCx43 is an inducible immune response gene and an important conduit for immune challenge-induced extracellular ATP release in fish.

Anti-inflammatory Effect of Methyl Gallate on Experimental Arthritis: Inhibition of Neutrophil Recruitment, Production of Inflammatory Mediators, and Activation of Macrophages.

Methyl gallate (MG) is a prevalent phenolic acid in the plant kingdom, and its presence in herbal medicines might be related to its remarkable biological effects, such as its antioxidant, antitumor, and antimicrobial activities. Although some indirect evidence suggests anti-inflammatory activity for MG, there are no studies demonstrating this effect in animal models. Herein, we demonstrated that MG (0.7-70 mg/kg) inhibited zymosan-induced experimental arthritis in a dose-dependent manner. The oral administration of MG (7 mg/kg) attenuates arthritis induced by zymosan, affecting edema formation, leukocyte migration, and the production of inflammatory mediators (IL-1ß, IL-6, TNF-α, CXCL-1, LTB4, and PGE2). Pretreatment with MG inhibited in vitro neutrophil chemotaxis elicited by CXCL-1, as well as the adhesion of these cells to TNF-α-primed endothelial cells. MG also impaired zymosan-stimulated macrophages by inhibiting IL-6 and NO production, COX-2 and iNOS expression, and intracellular calcium mobilization. Thus, MG is likely to present an anti-inflammatory effect by targeting multiple cellular events such as the production of various inflammatory mediators, as well as leukocyte activation and migration.

Oral immunostimulation of the oyster Ostrea edulis: Impacts on the parasite Bonamia ostreae.

Bioactive compounds were orally administered to the native European oyster Ostrea edulis to evaluate the immune response and the progression of infection of the protozoan parasite Bonamia ostreae. The immunostimulants lipopolysaccharide and zymosan directly administrated to the water column induced an increase in lysozyme activity and the percentage of granulocytes in naïve oysters over a period of 7 days. In another set of experiments, zymosan and curdlan were microencapsulated in alginate and also administered to the water column to naïve and B. ostreae infected O. edulis. Oyster mortality, prevalence and intensity of infection and several immune parameters were evaluated up to 28 days post-administration. Lysozyme activity, nitric oxide production and the expression of galectin, lysozyme and superoxide dismutase increased after 24 h in both infected and uninfected oysters. Zymosan immunostimulated oysters displayed a decrease in the prevalence of B. ostreae infection not attributed to mortalities but which could be associated to the enhanced ability of immunostimulants to evoke an enhanced immune response in the oysters and reduce infection.

Assessing the immunomodulatory potential of high-molecular-weight extracts from mushrooms; an assay based on THP-1 macrophages.

BACKGROUND: Food is a potential source of immunomodulating compounds that may be used to steer immune responses towards a desired status such as reducing inflammatory disorders. However, to identify and characterize such bioactive compounds, biologically relevant and standardized assays are required. Macrophages play an important role in immunomodulation and are suited for developing cell-based assays. An assay was developed based on macrophages, in a homogeneous differentiation state, using the human monocytic cell line THP-1 previously used to assess immunomodulatory properties of low-molecular-weight allergens, hormones, dietary supplements and therapeutic drugs. RESULTS: Zymosan and mushroom polysaccharide extracts lead to a heterogeneous differentiation state of THP-1 monocytes, and these cells secrete low levels of cytokines upon stimulation. Differentiation into macrophages using a low concentration of phorbol 12-myristate 13-acetate improved responsiveness. Elevated levels of cytokines were secreted by cells in a homogenous differentiation state. In addition, it was determined that the assay performs best when using cells at a concentration of (2.5-5) × 10(5) cells mL(-1). CONCLUSION: An assay was developed suitable to distinguish the immunomodulatory properties of food compounds in a reproducible manner. It was evaluated using eight mushroom species by measuring the secretion of relevant cytokines TNF-α, IL-1ß, IL-6 and IL-10.

Anti-inflammatory effects of retinoids and carotenoid derivatives on caspase-3-dependent apoptosis and efferocytosis of bovine neutrophils.

OBJECTIVE: To evaluate immunomodulatory properties of all-trans retinoic acid and a fully oxidized ß-carotene dietary product in calves with Mannheimia haemolytica-induced pneumonia. ANIMALS: Twenty-five 6- to 10-week-old male Holstein calves for experimental inoculations and three 8- to 30-week-old Angus heifers for blood donations. PROCEDURES: In vitro, neutrophils and monocyte-derived macrophages isolated from blood of healthy Angus heifers were treated with all-trans retinoic acid (1 µM) or fully oxidized ß-carotene (8.3 µg/mL) for various times and assessed for markers of cellular death, antimicrobial function, and production of proinflammatory leukotriene B4. Following 28 days of dietary supplementation with fully oxidized ß-carotene, Holstein calves were experimentally inoculated with M haemolytica. Bronchoalveolar lavage fluid was collected at 3 and 24 hours after challenge inoculation and analyzed for markers of apoptosis. RESULTS: In vitro, all-trans retinoic acid and fully oxidized ß-carotene induced cell-selective, caspase-3-dependent apoptosis in neutrophils, which subsequently enhanced efferocytosis in macrophages. Conversely, neither treatment altered phorbol 12-myristate 13-acetate-induced oxidative burst, phagocytosis of nonopsonized zymosan (complement or antibody independent), or M haemolytica-induced leukotriene B4 production in bovine neutrophils. In vivo, fully oxidized ß-carotene enhanced leukocyte apoptosis in bronchoalveolar lavage fluid as well as subsequent efferocytosis by macrophages without altering numbers of circulating leukocytes. CONCLUSIONS AND CLINICAL RELEVANCE: Neutrophil apoptosis and subsequent efferocytosis by macrophages are key mechanisms in the resolution of inflammation. Findings for the present study indicated that all-trans retinoic acid and fully oxidized ß-carotene could be novel nutraceutical strategies that may confer anti-inflammatory benefits for cattle with respiratory tract disease.

The unfolded protein response and the phosphorylations of activating transcription factor 2 in the trans-activation of il23a promoter produced by ß-glucans.

Current views on the control of IL-23 production focus on the regulation of il23a, the gene encoding IL-23 p19, by NF-κB in combination with other transcription factors. C/EBP homologous protein (CHOP), X2-Box-binding protein 1 (XBP1), activator protein 1 (AP1), SMAD, CCAAT/enhancer-binding protein (C/EBPß), and cAMP-response element-binding protein (CREB) have been involved in response to LPS, but no data are available regarding the mechanism triggered by the fungal mimic and ß-glucan-containing stimulus zymosan, which produces IL-23 and to a low extent the related cytokine IL-12 p70. Zymosan induced the mobilization of CHOP from the nuclear fractions to phagocytic vesicles. Hypha-forming Candida also induced the nuclear disappearance of CHOP. Assay of transcription factor binding to the il23a promoter showed an increase of Thr(P)-71-Thr(P)-69-activating transcription factor 2 (ATF2) binding in response to zymosan. PKC and PKA/mitogen- and stress-activated kinase inhibitors down-regulated Thr(P)-71-ATF2 binding to the il23a promoter and il23a mRNA expression. Consistent with the current concept of complementary phosphorylations on N-terminal Thr-71 and Thr-69 of ATF2 by ERK and p38 MAPK, MEK, and p38 MAPK inhibitors blunted Thr(P)-69-ATF2 binding. Knockdown of atf2 mRNA with siRNA correlated with inhibition of il23a mRNA, but it did not affect the expression of il12/23b and il10 mRNA. These data indicate the following: (i) zymosan decreases nuclear proapoptotic CHOP, most likely by promoting its accumulation in phagocytic vesicles; (ii) zymosan-induced il23a mRNA expression is best explained through coordinated κB- and ATF2-dependent transcription; and (iii) il23a expression relies on complementary phosphorylation of ATF2 on Thr-69 and Thr-71 dependent on PKC and MAPK activities.

Alcohol- and water-based extracts obtained from Rhodiola rosea affect differently the number and metabolic activity of circulating granulocytes in Balb/c mice.

INTRODUCTION AND OBJECTIVE: Rhodiola rosea (RR) rhizomes with roots extracts are traditional natural drugs originated from Asia and now commonly used as adaptogens and antidepressants. The aim of this work was to study the in vivo effect of aqueous (RRW) and 50% hydro-alcoholic (RRA) extracts on the number and metabolic activity of blood granulocytes in mice. MATERIAL AND METHODS: Mice were fed for 7 days RR extract in daily doses 0.05, 0.1, 0.2 or 0.4 mg. The metabolic activity of blood granulocytes was determined by measuring of their luminol-dependent chemiluminescent activity in scintillation counter, after zymosan stimulation. RESULTS: Number of blood granulocytes was diminished and their chemiluminescence was enhanced in all groups of mice fed R.rosea hydro-alcoholic extract. Aqueous extract (RRW) was ineffective in all doses applied. CONCLUSION: This study revealed difference in the number and metabolic activity of granulocytes mice fed RRA or RRW extracts. Immune characteristics of some individual compounds from RRA and RRW extracts, selected by HPLC analysis, should be carried out in the next experiments.

Tephrosia toxicaria†Pers. reduces temporomandibular joint inflammatory hypernociception: the involvement of the HO-1 pathway.

BACKGROUND: We investigated both the efficacy and the sub-chronic toxicity of Tephrosia toxicaria Pers. in the zymosan-induced temporomandibular joint (TMJ) inflammatory hypernociception in rats evaluating the possible role of heme oxygenase-1 (HO-1). METHODS: Rats were pretreated with T. toxicaria (0.2, 2.0 or 20 mg/kg) 60 min before the intra-articular injection of zymosan (2 mg, 40 µL) in the left TMJ. In another series of experiments, rats were treated with ZnPP-IX (3 mg/kg), a specific HO-1 inhibitor, before T. toxicaria (20 mg/kg). Von Frey test was used to evaluate inflammatory hypernociception (g) 4 h after zymosan injection. Six hours after zymosan injection, the synovial lavage was collected for total cell count and myeloperoxidase (MPO) activity, and joint tissue for histopathological analysis and immunohistochemistry for HO-1. To evaluate the sub-chronic toxicity, mice received T. toxicaria (20 mg/kg) or saline once a day for 14 days to analyse body mass, organ weight and biochemical parameters. RESULTS: T. toxicaria partially reversed the zymosan-induced head withdrawal threshold, the number of cells and the MPO activity. T. toxicaria reduced the inflammatory cell influx in the synovial membrane. TMJ immunohistochemical analyses treated with T. toxicaria showed increased HO-1 expression. These effects of T. toxicaria were not observed in the presence of ZnPP-IX. T. toxicaria treatment for 14 days did not show significant signs of toxicity when administrated to mice. CONCLUSIONS: T. toxicaria did not produce any signs of toxicity and effectively decreased zymosan-induced TMJ inflammatory hypernociception dependent, at least in part, upon the HO-1 pathway integrity.

Oxidative burst and nitric oxide responses in carp macrophages induced by zymosan, MacroGard(®) and selective dectin-1 agonists suggest recognition by multiple pattern recognition receptors.

ß-Glucans are glucose polymers that are found in the cell walls of plants, bacteria, certain fungi, mushrooms and the cell wall of baker's yeast. In mammals, myeloid cells express several receptors capable of recognizing ß-glucans, with the C-type lectin receptor dectin-1 in conjunction with Toll-like receptor 2 (TLR2), considered key receptors for recognition of ß-glucan. In our studies to determine the possible involvement of these receptors on carp macrophages a range of sources of ß-glucans were utilized including particulate ß-glucan preparations of baker's yeast such as zymosan, which is composed of insoluble ß-glucan and mannan, and MacroGard(®), a ß-glucan-based feed ingredient for farmed animals including several fish species. Both preparations were confirmed TLR2 ligands by measuring activation of HEK293 cells transfected with human TLR2 and CD14, co-transfected with a secreted embryonic alkaline phosphatase (SEAP) reporter gene. In addition, dectin-1-specific ligands in mammals i.e. zymosan treated to deplete the TLR-stimulating properties and curdlan, were monitored for their effects on carp macrophages by measuring reactive oxygen and nitrogen radicals production, as well as cytokine gene expression by real-time PCR. Results clearly show the ability of carp macrophages to strongly react to particulate ß-glucans with an increase in the production of reactive oxygen and nitrogen radicals and an increase in cytokine gene expression, in particular il-1ß, il-6 and il-11. We identified carp il-6, that was previously unknown. In addition, carp macrophages are less, but not unresponsive to selective dectin-1 agonists, suggesting recognition of ß-glucans by multiple pattern recognition receptors that could include TLR but also non-TLR receptors. Candidate receptors for recognition of ß-glucans are discussed.

Zymosan activates protein kinase A via adenylyl cyclase VII to modulate innate immune responses during inflammation.

Pathogens use a variety of strategies to evade host immune defenses. A powerful way to suppress immune function is to increase intracellular concentrations of cAMP in host immune cells, which dampens inflammatory responses and prevents microbial killing. We found that the yeast cell wall extract, zymosan, is capable of increasing intracellular cAMP and activates the protein kinase A pathway in bone marrow derived macrophage (BMDM) cells from mice. This response is dependent on adenylyl cyclase type VII (AC7) and heterotrimeric G proteins, primarily G(12/13). Consequently, zymosan induced production of the inflammatory cytokine, TNFα, was much stronger in BMDMs from AC7 deficient mice compared to the response in wild type cells. In a model of zymosan induced peritonitis, mice deficient of AC7 in the myeloid lineage displayed prolonged inflammation. We propose that zymosan induced increases in cAMP and activation of PKA serve as a mechanism to dampen inflammatory responses in host cells, which consequently favors the survival of microbes. This would also help explain a well documented phenomenon, that the ability of zymosan to stimulate inflammatory cytokine responses via TLR2 appears to be weaker than other stimuli of TLR2.

Efficacy and toxicity of intravenous iron in a mouse model of critical care anemia*.

OBJECTIVE: Anemia is common in critically ill patients, due to inflammation and blood loss. Anemia can be associated with iron deficiency and low serum hepcidin levels. However, iron administration in this setting remains controversial because of its potential toxicity, including oxidative stress induction and sepsis facilitation. The objective of this work was to determine the efficacy and toxicity of iron administration using a mouse model mimicking critical care anemia as well as a model of acute septicemia. DESIGN: Prospective, randomized, open label controlled animal study. SETTING: University-based research laboratory. SUBJECTS: C57BL/6 and OF1 mice. INTERVENTIONS: Intraperitoneal injection of zymosan inducing generalized inflammation in C57BL/6 mice, followed in our full model by repeated phlebotomies. A dose equivalent to 15 mg/kg of ferric carboxymaltose was injected intravenously on day 5. To assess the toxicity of iron in a septicemia model, OF1 mice were simultaneously injected with iron and different Escherichia coli strains. MEASUREMENTS AND MAIN RESULTS: To investigate the effect of iron on oxidative stress, we measured reactive oxygen species production in the blood using luminol-amplified chemiluminescence and superoxide dismutase 2 messenger RNA levels in the liver. These markers of oxidative stress were increased after iron administration in control mice but not in zymosan-treated mice. Liver catalase messenger RNA levels decreased in iron-treated control mice. Iron administration was not associated with increased mortality in the septicemia model or in the generalized inflammation model. Iron increased hemoglobin levels in mice fed with a low iron diet and subjected to phlebotomies and zymosan 2 wks after treatment administration. CONCLUSIONS: Adverse effects of intravenous iron supplementation by ferric carboxymaltose seem to be minimal in our animal models. Furthermore, iron appears to be effective in correcting anemia, despite inflammation. Studies of efficacy and safety of iron in critically ill patients are warranted.

Inflammation inhibits the expression of phosphoenolpyruvate carboxykinase in liver and adipose tissue.

Inhibition of adipocyte triglyceride biosynthesis is required for fatty acid mobilization during inflammation. Triglyceride biosynthesis requires glycerol 3-phosphate and phosphoenolpyruvate carboxykinase (PEPCK) plays a key role. We demonstrate that LPS, zymosan, and TNF-α decrease PEPCK in liver and fat. Turpentine decreases PEPCK in liver, but not in fat. The LPS-induced decrease in PEPCK does not occur in TLR4 deficient animals, indicating that this receptor is required. The LPS-induced decrease in hepatic PEPCK does not occur in TNF receptor/IL-1 receptor knockout mice, but occurs in fat, indicating that TNF-α/IL-1 is essential for the decrease in liver but not fat. In 3T3-L1 adipocytes TNF-α, IL-1, IL-6, and IFNγ inhibit PEPCK indicating that there are multiple pathways by which PEPCK is decreased in adipocytes. The binding of PPARγ and RXRα to the PPARγ response element in the PEPCK promoter is markedly decreased in adipose tissue nuclear extracts from LPS treated animals. Lipopolysaccharide and zymosan reduce PPARγ and RXRα expression in fat, suggesting that a decrease in PPARγ and RXRα accounts for the decrease in PEPCK. Thus, there are multiple cytokine pathways by which inflammation inhibits PEPCK expression in adipose tissue which could contribute to the increased mobilization of fatty acids during inflammation.

Medicinal mushroom Lingzhi or Reishi, Ganoderma lucidum (W.Curt.:Fr.) P. Karst., beta-glucan induces Toll-like receptors and fails to induce inflammatory cytokines in NF-kappaB inhibitor-treated macrophages.

Beta-Glucan of medicinal Lingzhi or Reishi mushroom, Ganoderma lucidum (BGG), possesses immunostimulatory and anti-tumor activities. Innate immune cells are activated by the binding of beta-glucan to the dectin-1 receptor. The present study investigated the immunostimulating activities of BGG, including binding to dectin-1, secretion of cytokines and reactive oxygen species, and induction of Toll-like receptors (TLRs) in RAW264.7 mouse macrophages. Reverse transcription-polymerase chain reaction and flow cytometry were used for the cytokine and TLR analyses. A mouse inflammation antibody array was used for protein-level cytokine analysis. BGG bound to dectin-1 and induced RAW264.7 cell secretion of several cytokines, including granulocyte colony-stimulating factor, interleukin (IL)-6, regulated upon activation normal T cell expressed and secreted (RANTES), tissue inhibitor of metalloproteinase-1, and tumor necrosis factor-alpha. The secretion of these cytokines was further increased by the addition of lipopolysaccharide (LPS). BGG also induced both nitric oxide and inducible nitric oxide synthase (iNOS). Treatment with an inhibitor of nuclear factor-kappa B (NF-kappaB) reduced the induction of IL-1, IL-6, and iNOS in a concentration-dependent manner. Expressions of TLR2, TLR4, and TLR6 were increased by BGG treatment, and addition of LPS induced further induction of TLR4 and TLR6. Our result indicates that BGG induces macrophage secretion of inflammatory cytokines, which can be potentiated by the presence of LPS, likely by binding to dectin-1 and TLR-2/6 receptors, which activate NF-kappaB and prompt the secretion of cytokines.

Genomic characterization, phylogeny and gene regulation of g-type lysozyme in sole (Solea senegalensis).

The g-type lysozyme is a key protein of the innate immune system to fight bacterial infections. In this study we cloned and characterized the gene encoding for g-type lysozyme in Senegalese sole (Solea senegalensis). The deduced amino acid sequence comprised 195 residues containing the three conserved catalytic residues and two cysteines. A BAC analysis revealed that the gene is structured in 5 exons and 4 introns. Also, two polyadenylation signals that generate two cDNAs differing in 3'-UTR length were detected. Promoter analysis showed the presence of the main cis-acting elements involved in the transcriptional regulation of the gene. At genomic level, the g-type lysozyme was associated with mucolipin 1 and the peptidoglycan recognition protein 2 conforming a cluster of antidefensive genes with a well-conserved synteny across Percomorpha. FISH analysis using the BAC clone revealed a single hybridization signal located in an acrocentric chromosome pair. The phylogenetic analysis confirmed that the g-type lysozyme represents a complex group in fish that has been shaped by gene duplications and diversification with several positions under Darwinian selection. Expression analysis in juvenile tissues indicated that transcript levels were higher in gills, spleen and heart. During development, gene expression activated just at the beginning of metamorphosis, increasing progressively until climax. Hormonal treatments demonstrated that this gene was regulated positively by thyroid hormones during development and negatively by dexamethasone. In contrast, no response was observed after all-trans retinoic acid or 4-diethylaminobenzaldehyde treatments. Finally, treatments using lipopolysaccharide, lipoteichoic acid, peptidoglycan, zymosan and poly(I:C) activated gene expression in a time- and tissue-specific manner. Taken together, data indicate that g-type lysozyme is a high evolutionary conserved gene that diversified to adapt to changing environment and pathogen conditions. Gene expression can be activated by diverse pathogen stimuli and modulated by physiological factors with important consequences for the aquaculture of this species.