Increased Nitrite Production Research Articles

Stable continuous flow CANDAN process transitioning from anammox UASB reactor by facilitating indigenous nitrite-producing denitrification community

The emerging nitrogen removal process known as CANDAN (Complete Ammonium and Nitrate removal via Denitratation-Anammox over Nitrite) has been developed in Sequencing Batch Reactors (SBRs). Yet, starting up and maintaining stability in continuous-flow reactors remain challenging. This study explores the feasibility of transitioning the CANDAN process from an anammox-dominated process by introducing appropriate external organics to facilitate indigenous nitrite-producing denitrification community in an Upflow Anaerobic Sludge Blanket (UASB) reactor. 150-day operation results indicate that under feeding rates of domestic wastewater at 0.54 L/h and nitrate-containing wastewater at 1.08 L/h, excellent N removal was achieved, with effluent TN below 10.0 mg N/L. Adding external sodium acetate at a COD/NO3−-N = 2.0 triggered denitratation, ex-situ denitrification activity tests showed increased nitrite production rates, maintaining the nitrate-to-nitrite transformation ratio (NTR) above 90 %. Consequently, anammox activity was consistently maintained, dominating Total Nitrogen (TN) removal with a contribution as high as 78.3 ± 8.0 %. Anammox functional bacteria, Brocadia and Kuenenia were identified and showed no decrease throughout the operation, indicating the robustness of the anammox process. Notably, the troublesome of sludge flotation, did not occur, also contributing to sustained outstanding performance. In conclusion, this study advances our understanding of the synergistic interplay between anammox and denitrifying bacteria in the Anammox-UASB system, offering technical insights for establishing a stable continuous-flow CANDAN process for simultaneous ammonium and nitrate removal.

C1q/Tumor Necrosis Factor-Related Protein-9 Is a Novel Vasculoprotective Cytokine That Restores High Glucose-Suppressed Endothelial Progenitor Cell Functions by Activating the Endothelial Nitric Oxide Synthase.

This study investigated whether gCTRP9 (globular C1q/tumor necrosis factor-related protein-9) could restore high-glucose (HG)-suppressed endothelial progenitor cell (EPC) functions by activating the endothelial nitric oxide synthase (eNOS). EPCs were treated with HG (25 mmol/L) and gCTRP9. Migration, adhesion, and tube formation assays were performed. Adiponectin receptor 1, adiponectin receptor 2, and N-cadherin expression and AMP-activated protein kinase, protein kinase B, and eNOS phosphorylation were measured by Western blotting. eNOS activity was determined using nitrite production measurement. Invivo reendothelialization and EPC homing assays were performed using Evans blue and immunofluorescence in mice. Treatment with gCTRP9 at physiological levels enhanced migration, adhesion, and tube formation of EPCs. gCTRP9 upregulated the phosphorylation of AMP-activated protein kinase, protein kinase B, and eNOS and increased nitrite production in a concentration-dependent manner. Exposure of EPCs to HG-attenuated EPC functions induced cellular senescence and decreased eNOS activity and nitric oxide synthesis; the effects of HG were reversed by gCTRP9. Protein kinase B knockdown inhibited eNOS phosphorylation but did not affect gCTRP9-induced AMP-activated protein kinase phosphorylation. HG impaired N-cadherin expression, but treatment with gCTRP9 restored N-cadherin expression after HG stimulation. gCTRP9 restored HG-impaired EPC functions through both adiponectin receptor 1 and N-cadherin-mediated AMP-activated protein kinase /protein kinase B/eNOS signaling. Nude mice that received EPCs treated with gCTRP9 under HG medium showed a significant enhancement of the reendothelialization capacity compared with those with EPCs incubated under HG conditions. CTRP9 promotes EPC migration, adhesion, and tube formation and restores these functions under HG conditions through eNOS-mediated signaling mechanisms. Therefore, CTRP9 modulation could eventually be used for vascular healing after injury.

A synergistic blend of Garcinia mangostana fruit rind and Cinnamomum tamala leaf extracts enhances myogenic differentiation and mitochondrial biogenesis in vitro and muscle growth and strength in mice.

A proprietary combination of Garcinia mangostana fruit rind and Cinnamomum tamala leaf extracts (LI80020F4, CinDura®) improved the physical performance and muscle strength of resistance-trained adult males. This study assessed the underlying mechanisms of the ergogenic potential of LI80020F4 in in vitro and in vivo models. The individual extracts and their combination (LI80020F4) were assessed for nitrite production in EAhy926 human endothelial cells. Subsequent experiments evaluated the effect of LI80020F4 in myotube formation in C2C12 mouse myoblasts, expression of mammalian target of rapamycin (mTOR) signaling proteins, myogenic factors, and mitochondrial functions in L6 rat myoblasts.Moreover, adult male ICR mice were randomly assigned (n = 15) into vehicle control (G1), exercise alone (G2), oxymetholone-16 mg/kg body weight (bw) (G3), and 75 (G4)-, 150 (G5)-, or 300 (G6) mg/kg bw of LI80020F4, orally gavaged for 28 days. G1 and G2 mice received 0.5% carboxymethylcellulose sodium. Following completion, muscle strength and physical performance were assessed on forelimb grip strength and forced swimming test (FST), respectively. Gastrocnemius (GA), tibialis anterior (TA) muscle weights, muscle fiber cross-sectional area (CSA), levels of muscle, and serum protein markers were also determined. LI80020F4 increased nitrite production in EAhy926 cells in a dose-dependent manner. LI80020F4 induced C2C12 myotube formation, increased mitochondrial biogenesis, upregulated the expressions of activated mTOR and other mitochondria and myogenic proteins, and mitigated H2O2-induced mitochondrial membrane depolarization in the myoblast cells. In the animal study, 75, 150, and 300 mg/kg bw LI80020F4 doses significantly (P < 0.05) increased the animals' forelimb grip strength. Mid- and high-dose groups showed increased swimming time, increased muscle weight, CSA, muscle growth-related, and mitochondrial protein expressions in the GA muscles. LI80020F4 increases nitric oxide production in the endothelial cells, mitochondrial biogenesis and function, upregulates skeletal muscle growth-related protein expressions and reduces oxidative stress; together, it explains the basis of the ergogenic potential of LI80020F4.

Nitric Oxide Production in mixed cultures of infected rats with Neospora caninum and treated with Jataí Honey (Tetragonisca angustula)

Neosporosis is a disease caused by Neospora caninum sp (JP Dubey), an intracellular parasite that affects many animal species, fostering abortions and neurological disorders. Recent studies on Neospora caninum have shown that glial cells have been considered a model of in vitro infections of these protozoa. Honey has been used since ancient times for its anti-inflammatory and antimicrobial properties. The present study aimed to evaluate the in vitro reactivity of glial cells (astrocytes and microglia) infected with N. caninum treated with Jataí honey at 1% (Tetragonisca angustula). After 72 hours from infection, mitochondrial metabolism, dehydrogenase lactate activity (LDH), nitric oxide production (NO) and the number of parasites were checked. Cultures treated with honey at 1% have shown mitochondrial metabolism and cell permeability increase. There was an increase in nitrite production, possible indicating a microglial activation. Nitric Oxide values found in this study may indicate an immune response against Neospora caninum tachyzoites, since such increase may contribute to reduce the number of tachyzoites. So, our results suggest that honey had a protective effect over astrocytes and microglia cultures infected with Neospora caninum.

Leishmanicidal Activity of Guanidine Derivatives against Leishmania infantum

Leishmaniasis is a neglected tropical infectious disease with thousands of cases annually; it is of great concern to global health, particularly the most severe form, visceral leishmaniasis. Visceral leishmaniasis treatments are minimal and have severe adverse effects. As guanidine-bearing compounds have shown antimicrobial activity, we analyzed the cytotoxic effects of several guanidine-bearing compounds on Leishmania infantum in their promastigote and amastigote forms in vitro, their cytotoxicity in human cells, and their impact on reactive nitrogen species production. LQOFG-2, LQOFG-6, and LQOFG-7 had IC50 values of 12.7, 24.4, and 23.6 µM, respectively, in promastigotes. These compounds exhibited cytotoxicity in axenic amastigotes at 26.1, 21.1, and 18.6 µM, respectively. The compounds showed no apparent cytotoxicity in cells from healthy donors. To identify mechanisms of action, we evaluated cell death processes by annexin V and propidium iodide staining and nitrite production. Guanidine-containing compounds caused a significant percentage of death by apoptosis in amastigotes. Independent of L. infantum infection, LQOFG-7 increased nitrite production in peripheral blood mononuclear cells, which suggests a potential mechanism of action for this compound. Therefore, these data suggest that guanidine derivatives are potential anti-microbial molecules, and further research is needed to fully understand their mechanism of action, especially in anti-leishmanial studies.

IMMU-22. REPROGRAMMING OF MICROGLIA/MACROPHAGES IN GLIOBLASTOMA IMPROVES ANTI-TUMOR T CELL RESPONSES

Abstract Glioma-infiltrating myeloid cells such microglia and macrophages (GAM) are a major component of the immunosuppressive tumor microenvironment in glioblastoma (GBM). Especially their anti-inflammatory M2-like activation state might counteract efficacy of immunotherapeutic interventions by impairing effector T cell infiltration and function. Therefore, we studied the ability of the small molecule inhibitors (SMI) PLX3397, BLZ945, and GW2580 that target the M2-associated colony stimulating factor-1 receptor (CSF1R) to shape GAM phenotype towards a pro-inflammatory M1-like phenotype and how this affects the T cell compartment.Upon treatment of freshly isolated CD11b-sorted GBM patient-derived GAMs (n = 15) a decreased expression of CD163 (M2-like) and an increased expression of HLA-DR (M1-like) as well as an increased nitrite production as an indirect measure for iNOS activation (M1-like) was observed which was most pronounced for BLZ945, and GW2580. Transcriptome analysis of treated vs. untreated GAMs supported a reprogramming towards a pro-inflammatory phenotype. In addition, treatment of GAMs in a GBM patient-derived tumor organoid model confirmed a substantial decrease of CD163+ M2-polarized GAM together with a reduced number of proliferating tumor cells. Finally, treatment of patient-derived GAMs led to an increased T cell transmigration through a dense barrier of autologous tumor-derived endothelial cells and increased the ability of T cells to kill autologous tumor cells. Our results support CSF1R blockade is able to reduce the immunosuppressive and pro-tumorigenic functions of GAM substantially and thereby could enhance the effectiveness of T cell-based immunotherapy.

Short-term exposure of the mayfly larvae (Cloeon dipterum, Ephemeroptera: Baetidae) to SARS-CoV-2-derived peptides and other emerging pollutants: A new threat for the aquatic environments

The input of SARS-CoV-2 or its fragments into freshwater ecosystems (via domestic or hospital sewage) has raised concerns about its possible impacts on aquatic organisms. Thus, using mayfly larvae [Cloeon dipterum (L.), Ephemeroptera: Baetidae] as a model system, we aimed to evaluate the possible effects of the combined short exposure of SARS-CoV-2-derived peptides (named PSPD-2001, PSPD-2002, and PSPD-2003 – at 266.2 ng/L) with multiple emerging pollutants at ambient concentrations. After six days of exposure, we observed higher mortality of larvae exposed to SARS-CoV-2-derived peptides (alone or in combination with the pollutant mix) and a lower-body condition index than those unexposed larvae. In the “PSPD” and “Mix+PSPD” groups, the activity of superoxide dismutase, catalase, DPPH radical scavenging activity, and the total thiol levels were also lower than in the “control” group. In addition, we evidenced the induction of nitrosative stress (inferred by increased nitrite production) and reduced acetylcholinesterase activity by SARS-CoV-2-derived peptides. On the other hand, malondialdehyde levels in larvae exposed to treatments were significantly lower than in unexposed larvae. The values of the integrated biomarker response index and the principal component analysis (PCA) results confirmed the similarity between the responses of animals exposed to SARS-CoV-2-derived peptides (alone and in combination with the pollutant mix). Although viral peptides did not intensify the effects of the pollutant mix, our study sheds light on the potential ecotoxicological risk associated with the spread of the new coronavirus in aquatic environments. Therefore, we recommend exploring this topic in other organisms and experimental contexts.

Exogenous Vitamin D3 Modulates Response of Bovine Macrophages to Mycobacterium avium subsp. paratuberculosis Infection and Is Dependent Upon Stage of Johne's Disease.

Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of ruminant enteritis, targets intestinal macrophages. During infection, macrophages contribute to mucosal inflammation and development of granulomas in the small intestine which worsens as disease progression occurs. Vitamin D3 is an immunomodulatory steroid hormone with beneficial roles in host-pathogen interactions. Few studies have investigated immunologic roles of 25-hydroxyvitamin D3 (25(OH)D3) and 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in cattle, particularly cattle infected with MAP. This study examined the effects of exogenous vitamin D3 on immune responses of monocyte derived macrophages (MDMs) isolated from dairy cattle naturally infected with MAP. MDMs were pre-treated with ± 100 ng/ml 25(OH)D3 or ± 4 ng/ml 1,25(OH)2D3, then incubated 24 hrs with live MAP in the presence of their respective pre-treatment concentrations. Following treatment with either vitamin D3 analog, phagocytosis of MAP by MDMs was significantly greater in clinically infected animals, with a greater amount of live and dead bacteria. Clinical cows had significantly less CD40 surface expression on MDMs compared to subclinical cows and noninfected controls. 1,25(OH)2D3 also significantly increased nitrite production in MAP infected cows. 1,25(OH)2D3 treatment played a key role in upregulating secretion of pro-inflammatory cytokines IL-1β and IL-12 while downregulating IL-10, IL-6, and IFN-γ. 1,25(OH)2D3 also negatively regulated transcripts of CYP24A1, CYP27B1, DEFB7, NOS2, and IL10. Results from this study demonstrate that vitamin D3 compounds, but mainly 1,25(OH)2D3, modulate both pro- and anti-inflammatory immune responses in dairy cattle infected with MAP, impacting the bacterial viability within the macrophage.

Eicosapentaenoic acid inhibits lipopolysaccharide (LPS)-induced nitrite production and cytokine release from J774 macrophages

Abstract Background Eicosapentaenoic acid (EPA), an omega-3 (ω-3) fatty acid, reduced cardiovascular (CV) events in high-risk patients (REDUCE-IT) but the mechanism is not fully understood. Activated macrophages, characterized by cytokine release and increased inducible nitric oxide synthase (iNOS) activity, contribute to atherosclerosis. As both a substrate for and potential inhibitor of cyclooxygenase (COX), EPA may reduce iNOS activity. Purpose The purpose of this study was to evaluate the dose-dependent effects of EPA on nitrite and cytokine release from lipopolysaccharide (LPS)-activated macrophages. Methods Murine J774 macrophages were pretreated with vehicle or EPA at 10, 20 and 40 μM for 2 h, then challenged with LPS at 1.0 μg/ml. After 24 hr, iNOS activity was measured by nitrite production using the Griess assay. EPA was compared to the COX inhibitor diclofenac at 1.0 μg/ml. Levels of interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) in cell supernatant were measured by immunochemistry using colchicine as a positive control. Results Activated macrophages caused a &amp;gt;4-fold increase in nitrite production (p&amp;lt;0.001) that was reduced by EPA in a dose-dependent manner. EPA decreased nitrite levels by 40, 62 and 77% at 10, 20 and 40 μM, respectively (p&amp;lt;0.01). Diclofenac separately reduced nitrite levels by 40% (p&amp;lt;0.01). EPA also reduced expression of IL-1β and TNF-α by 40% and 31%, respectively (p&amp;lt;0.01), in a manner similar to equimolar colchicine (10 μM). The reductions in IL-1β and TNF-α with EPA were dose-dependent. Conclusions EPA reduced macrophage activation as evidenced by decreased nitrite production and cytokine release similar to other anti-inflammatory agents. These findings indicate a novel effect of EPA on mechanisms of inflammation associated with vascular disease. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Amarin Pharma Inc., Elucida Research

EICOSAPENTAENOIC ACID INHIBITS LIPOPOLYSACCHARIDE (LPS)-INDUCED MACROPHAGE ACTIVATION THROUGH A POTENTIAL CYCLOOXYGENASE PATHWAY

<h3>BACKGROUND</h3> Activated macrophages, characterized by increased inducible nitric oxide synthase (iNOS) expression, participate in atherosclerosis and its complications. Cyclooxygenase (COX) regulates iNOS activity. As both a substrate for and potential inhibitor of COX, the omega-3 fatty acid, eicosapentaenoic acid (EPA), may reduce iNOS activity. Icosapent ethyl is an ethyl ester of EPA, and was shown to reduce ischemic events in high-risk patients (REDUCE-IT). We tested the effects of EPA on iNOS activity in lipopolysaccharide (LPS)-activated macrophages. <h3>METHODS AND RESULTS</h3> Murine J774 macrophages were pretreated with vehicle, EPA (10, 20, 40 µM), (10 µM) for 2 h, then challenged with LPS (1.0 µg/ml). After 24 h, iNOS activity was measured by nitrite production using the Griess assay. As a positive control, the COX inhibitor diclofenac was tested (1.0 µg/ml). Treatment with LPS increased nitrite production by 465% (p < 0.001). EPA treatment reduced nitrite production in a significant, dose-dependent manner by 40-77% at 10-40 µM, respectively, compared to LPS-alone. EPA at the lowest concentration tested produced an effect similar to diclofenac, which reduced nitrite levels by 40% (p < 0.01). <h3>CONCLUSION</h3> EPA reduced LPS-induced macrophage activation in a dose-dependent manner that was reproduced to a lesser extent by diclofenac. These findings indicate a novel effect of EPA on both COX and iNOS activity. The ability of EPA to reduce macrophage activity may contribute to limiting atherothrombotic risk as evidenced in REDUCE-IT.

Macrophage migration inhibitory factor as a therapeutic target after traumatic spinal cord injury: a systematic review.

Macrophages play an important role in mediating damage after Spinal cord injury (SCI) by secreting macrophage migration inhibitory factor (MMIF) as a secondary injury mediator. We aimed to systematically review the role of MMIF as a therapeutic target after traumatic SCI. Our systematic review has been performed according to the PRISMA 2009 Checklist. A systematic search in the scientific databases was carried out for studies published before 20 February 2019 from major databases. Two researchers independently screened titles. The risk of bias of eligible articles was assessed, and data were extracted. Finally, we systematically analyzed and interpreted related data. 785 papers were selected for the title and abstract screening. 12 papers were included for data extraction. Eight animal studies were of high quality and the remaining two were of medium quality. One of the two human studies was of poor quality and the other was of fair quality. MMIF as a pro-inflammatory mediator can cause increased susceptibility to glutamate-related neurotoxicity, increased nitrite production, increased ERK activation, and increased COX2/PGE2 signaling pathway activation and subsequent stimulation of CCL5-related chemotaxis. Two human studies and six animal studies demonstrated that MMIF level increases after SCI. MMIF inhibition might be a potential therapeutic target in SCI by multiple different mechanisms (6/12 studies). Most animal studies demonstrate significant neurologic improvement after administration of MMIF inhibitors, but these inhibitors have not been studied in humans yet. Further clinical trials are need to further understand MMIF inhibitor utility in acute or chronic SCI. Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Ectonucleotidases from trypomastigotes from different sources and various genetic backgrounds of Trypanosoma cruzi potentiate their infectivity and host inflammation

Distinct populations of Trypanosoma cruzi interact with mammalian cardiac muscle cells causing different inflammation patterns and low heart functionality. During T. cruzi infection, the extracellular ATP is hydrolyzed to tri- and/or diphosphate nucleotides, based on the infectivity, virulence, and regulation of the inflammatory response. T. cruzi carries out this hydrolysis through the T. cruzi ectonucleotidase, NTPDase-1 (TcNTPDase-1). This study aimed to evaluate the role of TcNTPDase-1 in culture rich in metacyclic trypomastigote forms (MT) and cell culture-derived trypomastigote forms (CT) from Colombiana (discrete typing unit - DTU I), VL-10 (DTU II), and CL (DTU VI) strains of T. cruzi. For this, we measured TcNTPDase-1 activity in suramin-treated and untreated parasites and infected J774 cells and C57BL/6 mice with suramin pre-treated parasites to assess parasitic and inflammatory cardiac profile in the acute phase of infection. Our data indicated a higher TcNTPDase-1 activity for ATP in culture rich in metacyclic trypomastigote forms from Colombiana strain in comparison to those from VL-10 and CL strains. The cell culture-derived trypomastigote forms from CL strain presented higher capacity to hydrolyze ATP than those from Colombiana and VL-10 strains. Suramin inhibited ATP hydrolysis in all studied parasite forms and strains. Suramin pre-treated parasites reduced J774 cell infection and increased nitrite production in vitro. In vivo studies showed a reduction of inflammatory infiltrate in the cardiac tissues of animals infected with cell culture-derived trypomastigote forms from suramin pre-treated Colombiana strain. In conclusion, TcNTPDase-1 activity in trypomastigotes forms drives part of the biological characteristics observed in distinct DTUs and may induce cardiac pathogenesis during T. cruzi infection.

4263 The cardioprotective effects of ramipril during the course of experimental hypercholesterolemia in rabbits

4263 The cardioprotective effects of ramipril during the course of experimental hypercholesterolemia in rabbits

P2Y12 Receptor Antagonist Clopidogrel Attenuates Lung Inflammation Triggered by Silica Particles.

Silicosis is an occupational lung disease caused by inhalation of silica particles. It is characterized by intense lung inflammation, with progressive and irreversible fibrosis, leading to impaired lung function. Purinergic signaling modulates silica-induced lung inflammation and fibrosis through P2X7 receptor. In the present study, we investigate the role of P2Y12, the G-protein-coupled subfamily prototype of P2 receptor class in silicosis. To that end, BALB/c mice received an intratracheal injection of PBS or silica particles (20 mg), without or with P2Y12 receptor blockade by clopidogrel (20 mg/kg body weight by gavage every 48 h) – groups CTRL, SIL, and SIL + Clopi, respectively. After 14 days, lung mechanics were determined by the end-inflation occlusion method. Lung histology was analyzed, and lung parenchyma production of nitric oxide and cytokines (IL-1β, IL-6, TNF-α, and TGF-β) were determined. Silica injection reduced animal survival and increased all lung mechanical parameters in relation to CTRL, followed by diffuse lung parenchyma inflammation, increased neutrophil infiltration, collagen deposition and increased pro-inflammatory and pro-fibrogenic cytokine secretion, as well as increased nitrite production. Clopidogrel treatment prevented silica-induced changes in lung function, and significantly reduced lung inflammation, fibrosis, as well as cytokine and nitrite production. These data suggest that inhibition of P2Y12 signaling improves silica-induced lung inflammation, preventing lung functional changes and mortality. Our results corroborate previous observations of silica-induced lung changes and expand the understanding of purinergic signaling in this process.

Effect and Mechanism of Phosphodiesterase Inhibitors on Trabecular Outflow.

PurposePhosphodiesterase (PDE) inhibitors increase matrix metalloproteinase (MMP) production by inhibiting re-uptake of adenosine and may potentiate nitric oxide (NO) activity. This study was performed to investigate the effects and mechanisms of PDE inhibitors on trabecular outflow in cultured human trabecular meshwork cells (HTMCs).MethodsPrimary HTMC cultures were exposed to 0, 20, and 50 µM dipyridamole (DPD) or theophylline (TPN). Permeability through the HTMC monolayer was assessed using carboxyfluorescein. The production of NO was assessed using the Griess assay and MMP-2 levels were measured via Western blotting.ResultsDPD significantly increased permeability accompanied with increased nitrite concentration and MMP-2 levels (all p < 0.05). TPN increased nitrite but did not affect permeability or MMP-2 levels significantly (p > 0.05). When treated with DPD and TPN together, both permeability and nitrite production were increased; however, MMP-2 levels showed no difference compared to DPD exposure alone (p > 0.05).ConclusionsDPD increased trabecular permeability accompanied with increased nitrite production and MMP-2 levels. PDE inhibitors may increase trabecular outflow by increasing MMP-2 levels and by potentiating NO activity through cyclic GMP in HTMC.

Aortic Response to Strength Training and Spirulina platensis Dependent on Nitric Oxide and Antioxidants.

Studies have shown that supplementation with Spirulina platensis improves vascular reactivity. However, it is unclear whether in association with strength training this effect can be enhanced. Thus, this study aimed to determine the effects of strength training and S. platensis on the reactivity of the aorta from Wistar rat and the possible mechanisms involved. The animals were supplemented with S. platensis and divided into sedentary (SG, SG50, SG150, and SG500) and trained groups (TG, TG50, TG150, and TG500). Nitrite, malondialdehyde (MDA) and antioxidant activity were determined by biochemical assays. To evaluate vascular response, cumulative concentration—response curves to phenylephrine (PHE) and acetylcholine (ACh) were constructed. L-NAME was used to assess the participation of nitric oxide (NO). It was observed that the PHE contractile potency was reduced in TG50, TG150, and TG500 groups compared to SG50, SG150, and SG500 groups, respectively. However, the presence of L-NAME increased the contractile response in all groups. Strength training potentiated the increase in relaxing activity induced by S. platensis, where the pCE50 values of ACh increased in TG150 and TG500. These responses were accompanied by increased nitrite production, MDA reduction and increased antioxidant activity in the aorta of both TG150 and TG500 groups. Thus, the present study demonstrated that combined with strength training, S. platensis potentiates vascular improvement through the participation of NO and reduction of oxidative stress.

Transcriptome analysis of alcohol-treated microglia reveals downregulation of beta amyloid phagocytosis

BackgroundMicroglial activation contributes to the neuropathology associated with chronic alcohol exposure and withdrawal, including the expression of inflammatory and anti-inflammatory genes. In the current study, we examined the transcriptome of primary rat microglial cells following incubation with alcohol alone, or alcohol together with a robust inflammatory stimulus.MethodsPrimary microglia were prepared from mixed rat glial cultures. Cells were incubated with 75 mM ethanol alone or with proinflammatory cytokines (“TII”: IL1β, IFNγ, and TNFα). Isolated mRNA was used for RNAseq analysis and qPCR. Effects of alcohol on phagocytosis were determined by uptake of oligomeric amyloid beta.ResultsAlcohol induced nitrite production in control cells and increased nitrite production in cells co-treated with TII. RNAseq analysis of microglia exposed for 24 h to alcohol identified 312 differentially expressed mRNAs (“Alc-DEs”), with changes confirmed by qPCR analysis. Gene ontology analysis identified phagosome as one of the highest-ranking KEGG pathways including transcripts regulating phagocytosis. Alcohol also increased several complement-related mRNAs that have roles in phagocytosis, including C1qa, b, and c; C3; and C3aR1. RNAseq analysis identified over 3000 differentially expressed mRNAs in microglia following overnight incubation with TII; and comparison to the group of Alc-DEs revealed 87 mRNAs modulated by alcohol but not by TII, including C1qa, b, and c. Consistent with observed changes in phagocytosis-related mRNAs, the uptake of amyloid beta1–42, by primary microglia, was reduced by alcohol.ConclusionsOur results define alterations that occur to microglial gene expression following alcohol exposure and suggest that alcohol effects on phagocytosis could contribute to the development of Alzheimer’s disease.

The Role of Mas Receptor and Bradykinin on Nitric Oxide Production Response to Angiotensin 1-7 in Ovariectomized Rats Treated with Estradiol

: Introduction: The angiotensin 1-7 (Ang1-7) Mas receptor (MasR) axis, bradykinin (BK) and female sex hormone are involved in releasing of vasodilatory biomarkers including Nitric Oxide (NO). We examined the role of MasR and BK on NO metabolite (nitrite) production response to Ang 1-7 infusion in ovariectomized rats treated with estradiol. Methods: A total of 48 female Wistar rats were divided into 2 main groups; ovariectomized treated with placebo (OVX) and ovariectomized treated with estradiol valerate (OVE) for period of two weeks. Then after anesthetization, the animals of each groups were divided into four subgroups that received MasR antagonist (A779) or , BK, BK+A779 or vehicle, and they were subjected to Ang1-7 infusion (0, 100, 300 and 1000 ng/kg/min). The level of nitrite (NO metabolite) was measured by Griess method. Results: The serum level of nitrite response to Ang 1-7 administration in OVE group was incrased when compared with OVX group, however when MasR was blocked by A799, the increased nitrite level was abolished. BK also increased the level of nitrite but co administration of BK and A779 did not enhance the nitrite level in both OVE and OVX groups. Conclusion: Estradiol and Bk increase nitrite production in response to Ang 1-7 infusion in condition of MasR presence.

The inhibitory effects of reject water on nitrifying populations grown at different biofilm thickness

Suppression of nitrite oxidizing bacteria (NOB) is of vital importance to achieve successful, energy efficient, mainstream anammox processes for wastewater treatment. In this study, biofilm carriers from a fully nitrifying MBBR system, fed with mainstream wastewater, were temporarily exposed to reject water from sludge dewatering, to evaluate this as a possible strategy to inhibit NOB and achieve nitrite production under realistic conditions. Two different carrier types were compared, in which biofilm thickness was maintained at approximately 400 and 50 μm, respectively, and reject treatment was tested at different exposure time and loading rates. Reject exposure almost always resulted in an increased nitrite production in the thinner biofilm, and overall, nitrifiers growing in the thin biofilm were more sensitive than those grown in the thicker biofilm. The effect from reject exposure remained in the systems for four days after returning to mainstream operation, with nitrite production gradually increasing for three days. Increased concentrations of free ammonia correlated with reject exposure and may be the cause of inhibition, although other factors cannot be excluded.

High salt induces autocrine actions of ET-1 on inner medullary collecting duct NO production via upregulated ETBreceptor expression

The collecting duct endothelin-1 (ET-1), endothelin B (ETB) receptor, and nitric oxide synthase-1 (NOS1) pathways are critical for regulation of fluid-electrolyte balance and blood pressure control during high-salt feeding. ET-1, ETB receptor, and NOS1 are highly expressed in the inner medullary collecting duct (IMCD) and vasa recta, suggesting that there may be cross talk or paracrine signaling between the vasa recta and IMCD. The purpose of this study was to test the hypothesis that endothelial cell-derived ET-1 (paracrine) and collecting duct-derived ET-1 (autocrine) promote IMCD nitric oxide (NO) production through activation of the ETB receptor during high-salt feeding. We determined that after 7 days of a high-salt diet (HS7), there was a shift to 100% ETB expression in IMCDs, as well as a twofold increase in nitrite production (a metabolite of NO), and this increase could be prevented by acute inhibition of the ETB receptor. ETB receptor blockade or NOS1 inhibition also prevented the ET-1-dependent decrease in ion transport from primary IMCDs, as determined by transepithelial resistance. IMCD were also isolated from vascular endothelial ET-1 knockout mice (VEETKO), collecting duct ET-1 KO (CDET-1KO), and flox controls. Nitrite production by IMCD from VEETKO and flox mice was similarly increased twofold with HS7. However, IMCD NO production from CDET-1KO mice was significantly blunted with HS7 compared with flox control. Taken together, these data indicate that during high-salt feeding, the autocrine actions of ET-1 via upregulation of the ETB receptor are critical for IMCD NO production, facilitating inhibition of ion reabsorption.