A targeted covalent small molecule inhibitor of HIV-1 fusion.

We describe a low molecular weight covalent inhibitor targeting a conserved lysine residue within the hydrophobic pocket of HIV-1 glycoprotein-41. The inhibitor bound selectively to the hydrophobic pocket and exhibited an order of magnitude enhancement of anti-fusion activity against HIV-1 compared to its non-covalent counterpart. The findings represent a significant advance in the quest to obtain non-peptide fusion inhibitors.

Sulfated Polysaccharides from Macroalgae Are Potent Dual Inhibitors of Human ATP-Hydrolyzing Ectonucleotidases NPP1 and CD39.

Extracellular ATP mediates proinflammatory and antiproliferative effects via activation of P2 nucleotide receptors. In contrast, its metabolite, the nucleoside adenosine, is strongly immunosuppressive and enhances tumor proliferation and metastasis. The conversion of ATP to adenosine is catalyzed by ectonucleotidases, which are expressed on immune cells and typically upregulated on tumor cells. In the present study, we identified sulfopolysaccharides from brown and red sea algae to act as potent dual inhibitors of the main ATP-hydrolyzing ectoenzymes, ectonucleotide pyrophosphatase/phosphodiesterase-1 (NPP1) and ecto-nucleoside triphosphate diphosphohydrolase-1 (NTPDase1, CD39), showing nano- to picomolar potency and displaying a non-competitive mechanism of inhibition. We showed that one of the sulfopolysaccharides tested as a representative example reduced adenosine formation at the surface of the human glioblastoma cell line U87 in a concentration-dependent manner. These natural products represent the most potent inhibitors of extracellular ATP hydrolysis known to date and have potential as novel therapeutics for the immunotherapy of cancer.

P-cresyl sulfate causes mitochondrial hyperfusion in H9C2 cardiomyoblasts.

Increased circulating level of uraemic solute p-cresyl sulphate (PCS) in patients with chronic kidney disease (CKD) is known to increase myocardial burden relevant to mitochondrial abnormalities. This study aimed at investigating mitochondrial response to PCS in H9C2 cardiomyoblasts. H9C2 cardiomyoblasts were treated with four different concentrations of PCS (3.125, 6.25, 12.5 and 25.0 µg/mL) to study the changes in cell proliferation, cell size and mitochondrial parameters including morphology, respiration, biogenesis and membrane potential. The lowest effective dose of PCS (6.25 µg/mL) induced mitochondrial hyperfusion with enhanced mitochondrial connectivity, mitochondrial oxygen consumption rates, mitochondrial mass, mitochondrial DNA copy number and increased volume of cardiomyoblasts. After PCS treatment, phosphorylation of energy-sensing adenosine monophosphate-activated protein kinase (AMPK) was increased without induction of apoptosis. In contrast, mitochondrial mass was recovered after AMPK silencing. Additionally, mitochondrial hyperfusion and cell volume were reversed after cessation of PCS treatment. The results of the present study showed that low-level PCS not only caused AMPK-dependent mitochondrial hyperfusion but also induced cell enlargement in H9C2 cardiomyoblasts in vitro.

Inhibition of Human Cytomegalovirus Entry into Host Cells Through a Pleiotropic Small Molecule.

Human cytomegalovirus (HCMV) infections are wide-spread among the general population with manifestations ranging from asymptomatic to severe developmental disabilities in newborns and life-threatening illnesses in individuals with a compromised immune system. Nearly all current drugs suffer from one or more limitations, which emphasizes the critical need to develop new approaches and new molecules. We reasoned that a 'poly-pharmacy' approach relying on simultaneous binding to multiple receptors involved in HCMV entry into host cells could pave the way to a more effective therapeutic outcome. This work presents the study of a synthetic, small molecule displaying pleiotropicity of interactions as a competitive antagonist of viral or cell surface receptors including heparan sulfate proteoglycans and heparan sulfate-binding proteins, which play important roles in HCMV entry and spread. Sulfated pentagalloylglucoside (SPGG), a functional mimetic of heparan sulfate, inhibits HCMV entry into human foreskin fibroblasts and neuroepithelioma cells with high potency. At the same time, SPGG exhibits no toxicity at levels as high as 50-fold more than its inhibition potency. Interestingly, cell-ELISA assays showed downregulation in HCMV immediate-early gene 1 and 2 (IE 1&2) expression in presence of SPGG further supporting inhibition of viral entry. Finally, HCMV foci were observed to decrease significantly in the presence of SPGG suggesting impact on viral spread too. Overall, this work offers the first evidence that pleiotropicity, such as demonstrated by SPGG, may offer a new poly-therapeutic approach toward effective inhibition of HCMV.

Study on the Material Basis of Neuroprotection of Myrica rubra Bark.

Background: Increasing attention has been given to the search for neuroprotective ingredients from natural plants. Myrica rubra bark (MRB) has been used in traditional oriental medicine for over thousand years and has potential neuroprotection. Methods and Results: Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was used to identify the compounds in MRB extract, and the MTT assay was performed to evaluate the neuroprotection of six major compounds from MRB against glutamate-induced damage in PC12 cells. The result displayed nineteen compounds were identified, and myricitrin and myricanol 11-sulfate were shown to have neuroprotection, which prevented cell apoptosis through alleviating oxidative stress by reducing the levels of reactive oxygen species and methane dicarboxylic aldehyde, as well as by enhancing the activities of superoxide dismutase. Conclusions: Several active compounds from MRB may offer neuroprotection and have the potential for the development of new drugs against central nervous system diseases.

Pharmacological prospection and structural characterization of two purified sulfated and pyruvylated homogalactans from green algae Codium isthmocladum.

Two sulfated polysaccharides (SPs), F2 and F3, isolated from Codium isthmocladum were found to contain galactose, sulfate, and pyruvate. The apparent molecular weights of F2 and F3 were determined to be 62 and 61 kDa, respectively. NMR spectroscopy combined with chemical analysis showed that F2 and F3 have the same structural features. However, F3 showed higher sulfate/sugar ratio (1/2.6) than F2 (1/4). F2 and F3 are essentially (1 → 3)-ß-D-galactans with some branching at C6. Pyruvylation occurs at O3 and O4, forming 3,4-O-(1-carboxyethylidene)-ß-D-Galp residues; some of these pyruvylated residues contain sulfate groups at C6. Some non-branching residues contain sulfate at C4. None of the SPs exhibited antioxidant activity. MTT results indicated that 1 mg/mL of both SPs about 40% of PANC-1 cell viability. At 10 µg/mL, F2 and F3 had 1.7-fold longer clotting times compared to that of Clexane® at the same concentration. The higher sulfate content of F3 is not a determining factor for pharmacological activities of galactans, considering that both F2 and F3 exerted the effects.

Structure, antiproliferative and cancer preventive properties of sulfated α-d-fucan from the marine bacterium Vadicella arenosi.

Sulfated fucose-containing glycopolymers are currently of great interest because of their wide spectrum of bioactivity, including anti-tumor properties. In this study, the structure of O-polysaccharide (OPS) of the marine bacterium Vadicella arenosi KMM 9024T, its effect on the proliferation of human breast cancer MCF-7 cells and cancer preventive properties were investigated. Two OPS fractions with different molecular weights were isolated and purified from the lipopolysaccharide by mild acid hydrolysis followed by anion-exchange chromatography. The OPS was found to consist of α-(1→3)-linked 2-O-sulfate-d-fucopyranosyl residues, whose structure was deduced by sugar analysis along with 2D NMR spectroscopy. The biological assay indicated that polysaccharide significantly reduced the proliferation and inhibited colony formation of MCF-7 cells in a dose-dependent manner. Besides, the experiment indicated the inhibitory role of polysaccharide on EGF-induced neoplastic cell transformation in mouse epidermal cells. The investigated polysaccharide is the first sulfated fucan isolated from the bacteria.

Sodium thiosulfate enhances production of polysaccharides and anticancer activities of sulfated polysaccharides in Antrodia cinnamomea.

Sulfated polysaccharides (SPSs) are polysaccharides (PSs) with high sulfate functionalization and possess bioactivities. This study aimed to increase the sulfate content of SPSs in Antrodia cinnamomea through sulfate feeding. Feeding A. cinnamomea with sodium thiosulfate was found to increase yields of PSs and SPSs in A. cinnamomea. The SPSs thus obtained (ST-SPS) were further isolated, showing enhanced sulfate content of 2.5 mmol/g. Sodium thiosulfate induced changes in molecular weight from 320 kDa to 1342 kDa, and area percentage of low-molecular-weight ST-SPS (< 20 kDa) was decreased. Functional studies revealed that sodium thiosulfate increased the ST-SPS anticancer efficacy in cancer cells via inhibition of EGFR/AKT signaling. Moreover, the ST-SPS enhanced synergistically cisplatin-, gefitinib- and 5 FU-induced cytotoxic effects in lung cancer H1975 cells and colon cancer CT26 cells. This study is the first to demonstrate that sodium thiosulfate induced changes in properties of A. cinnamomea with the anticancer mechanisms of ST-SPS.

Modulation of LPS-induced nitric oxide production in intestinal cells by hydroxytyrosol and tyrosol metabolites: Insight into the mechanism of action.

At intestinal level, after acute or chronic exposure to iNOS-derived NO, a toxic mechanism of action leads to inflammation and degenerative diseases. The aim of this study was to investigate the effect of glucuronide and sulfate metabolites of the extra virgin olive oil phenols tyrosol (Tyr) and hydroxytyrosol (HT), in comparison with their parent compounds, on the release of NO following exposure to a pro-inflammatory stimulus, the bacterial lipopolysaccharide (LPS). Human colon adenocarcinoma cells (Caco-2), differentiated as normal enterocytes, were treated with pathological concentrations of LPS, in order to stimulate iNOS pathway, which involves NF-ĸB activation through IĸBα phosphorylation and subsequent degradation induced by Akt or MAPKs. All the tested metabolites inhibited NO release induced by LPS, acting as inhibitors of iNOS expression, with an efficacy comparable to that of the parent compounds. HT and Tyr metabolites were effective in the inhibition of IĸBα degradation. No one of the compounds was able to inhibit Akt activation, whereas they modulated p38 and ERK1/2 MAPK. Obtained data show that HT and Tyr metabolites are able to prevent a pathological NO overproduction at intestinal level, where they concentrate, thus significantly contributing to the protective activity exerted by their parent compounds against inflammation.

Dereplication and targeted isolation of bioactive sulphur compound from bacteria isolated from a hydrothermal field.

Marine micro-organisms in the deep-sea hydrothermal vent systems are considered as potential sources of bioactive natural products. Sixteen bacterial strains were isolated from a deep-sea hydrothermal field and screened for bioactive metabolism studies. After the strains were subjected to bioactive testing at different culture media, chemical dereplication by HPLC coupled to high-resolution mass spectrometer was performed to analyse or determine the main secondary metabolisms in those strains. Strain 06204 was large-scale fermented with relative optimal media, for isolating the desired sulphur compound. Butyrolactone I 3-sulphate was isolated and structurally identified from the extract, guided by dereplication and showed moderate antivirus activities against H3N2 and EV71 viruses. Our study suggests that deep-sea hydrothermal bacteria are good sources of sulphur natural products. Meanwhile, the described approach, mainly bioactive screening, dereplication and targeted isolation, is effective and efficient to discover interesting bioactive compounds in hydrothermal bacteria.

Purification, structural analysis and mechanism of murine macrophage cell activation by sulfated polysaccharides from Cystoseira indica.

Sulfated polysaccharides were isolated and purified from the water extract of Cystoseira indica using DEAE Sepharose Fast Flow column to evaluate their structure and macrophage stimulating capacity. Crude and fractionated polysaccharides, CIF1 and CIF2, were mostly composed of neutral sugars (73.1%-78.6%) with relatively lower amounts of acidic sugars (1.3%-9.0%) and sulfate esters (6.9%-9.7%). The polymer chains of polysaccharides were mainly built of different levels of glucose (2.1%-30.8%), fucose (17.2%-24.4%), mannose (17.8%-20.6%) and galactose (16.7%-17.3%). The weight average molecular weight (Mw) of polysaccharides varied between 573.1 × 103 g/mol to 1146.6 × 103 g/mol. The CIF2 polysaccharide, as the most immunostimulating polysaccharide, remarkably induced the release of nitric oxide and inflammatory cytokines including TNF-α, IL-1ß, IL-6 and IL-10 from RAW264.7 murine macrophage cells through NF-κB and PAMKs transduction signaling pathways via cell surface TLR4. The interconnections of sugars in CIF2 polysaccharide were complex with (1→3)-fucopyranose, (1→2,3,4)-glucopyranose, (→1)-galactopyranose, (→1)-xylopyranose, (1→2)-rhamnopyranose and (1→2,3)-mannopyranose units being the most predominant residues.

The Potential of Fucose-Containing Sulfated Polysaccharides As Scaffolds for Biomedical Applications.

Marine environments have a high quantity and diversity of sulfated polysaccharides. In coastal regions brown algae are the most abundant biomass producers and their cell walls have fucosecontaining sulfated polysaccharides (FCSP), known as fucans and/or fucoidans. These sulfated compounds have been widely researched for their biomedical properties, namely the immunomodulatory, haemostasis, pathogen inhibition, anti-inflammatory capacity, and antitumoral. These activities are probably due to their ability to mimic the carbohydrate moieties of mammalian glycosaminoglycans. Therefore, the FCSP are interesting compounds for application in health-related subjects, mainly for developing scaffolds for delivery systems or tissue regeneration. FCSP showed potential for these applications also due to their ability to form stable 3D structures with other polymers able to entrap therapeutic agents or cell and growth factors, besides their biocompatibility and biodegradability. However, for the clinical use of these biopolymers well-defined reproducible molecules are required in order to accurately establish relationships between structural features and human health applications.

Characteristics of hERG and hNav1.5 channel blockade by sulcardine sulfate, a novel anti-arrhythmic compound.

Sulcardine sulfate (sulcardine) is a novel anti-arrhythmic compound, which blocks multiple channels and was shown to be safe and tolerated in clinical trials. The aim of the present study was to investigate the electrophysiological characteristics of sulcardine on the hERG and hNav1.5 channels. The hERG and hNav1.5 channels were heterologously stably expressed in human embryonic kidney 293 cells, and the effects of sulcardine on the hERG and hNav1.5 channels were recorded using the standard whole-cell patch-clamp technique. Sulcardine inhibited hERG channels in a concentration-dependent and reversible manner (IC50 = 94.3 µM). In addition, sulcardine shifted the activation curve of hERG channels to more negative potentials. The relative block of sulcardine on hERG channels was close to zero at the time point corresponding to channel opening, which was achieved by applying a depolarizing voltage, and quickly increased afterward. Sulcardine inhibited hNav1.5 channels in a concentration-dependent and reversible manner (IC50 = 15.0 µM) and shifted the inactivation curve of hNav1.5 channels to more negative potentials. The blockade of sulcardine on hNav1.5 channels was use-dependent. In conclusion, sulcardine is a potent hNav1.5 channel blocker with a mild inhibitory effect on hERG channels and preferentially binds to both hERG and hNav1.5 channels in the open and inactivated states rather than in the resting state.

Pro-apoptotic effect of Δ2-TGZ in "claudin-1-low" triple-negative breast cancer cells: involvement of claudin-1.

PURPOSE: 40% of triple-negative breast cancer (TNBC) do not express claudin-1, a major constituent of tight junction. Patients with these "claudin-1-low" tumors present a higher relapse incidence. A major challenge in oncology is the development of innovative therapies for such poor prognosis tumors. In this context, we study the anticancer effects of ∆2-TGZ, a compound derived from troglitazone (TGZ), on cell models of these tumors. METHODS AND RESULTS: In MDA-MB-231 and Hs578T "claudin-1-low" TNBC cells, Δ2-TGZ treatment induced claudin-1 protein expression and triggered apoptosis as measured by FACS analysis (annexin V/PI co-staining). Interestingly, in the non-tumorigenic human breast epithelial cell line MCF-10A, the basal level of claudin-1 was not modified following Δ2-TGZ treatment, which did not induce apoptosis. Furthermore, claudin-1-transfected MDA-MB-231 and Hs578T cells displayed a significant increase of cleaved PARP-1 and caspase 7, caspase 3/7 activities, and TUNEL staining. RNA interference was performed in order to inhibit Δ2-TGZ-induced claudin-1 expression in both the cells. In absence of claudin-1, a decrease of cleaved PARP-1 and caspase 7 and caspase 3/7 activities were observed in MDA-MB-231 but not in Hs578T cells. CONCLUSION: Claudin-1 overexpression and Δ2-TGZ treatment are associated to apoptosis in MDA-MB-231 and Hs578T "claudin-1-low" TNBC. Moreover, in MDA-MB-231 cells, claudin-1 is involved in the pro-apoptotic effect of Δ2-TGZ. Our results suggest that claudin-1 re-expression could be an interesting therapeutic strategy for "claudin-1-low" TNBC.

Ferulic acid-4-O-sulfate rather than ferulic acid relaxes arteries and lowers blood pressure in mice.

Consumption of foods rich in ferulic acid (FA) such as wholegrain cereals, or FA precursors such as chlorogenic acids in coffee, is inversely correlated with risk of cardiovascular disease and type 2 diabetes. As a result of digestion and phase II metabolism in the gut and liver, FA is converted predominantly into ferulic acid-4-O-sulfate (FA-sul), an abundant plasma metabolite. Although FA-sul is the main metabolite, very little has been reported regarding its bioactivities. We have compared the ex vivo vasorelaxing effect of FA and FA-sul (10-7-3.10-5M) on isolated mouse arteries mounted in tissue myographs. FA-sul, but not FA, elicited a concentration-dependent vasorelaxation of saphenous and femoral arteries and aortae. The FA-sul-mediated vasorelaxation was blunted by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a soluble guanylate cyclase (sGC) inhibitor. The role of sGC was confirmed in femoral arteries isolated from sGCα1(-/-) knockout mice. Furthermore, 4-aminopyridine, a specific inhibitor of voltage-dependent potassium channels, significantly decreased FA-sul-mediated effects. In anesthetized mice, intravenous injection of FA-sul decreased mean arterial pressure, whereas FA had no effect, confirming the results obtained ex vivo. FA-sul is probably one of the major metabolites accounting for the blood pressure-lowering effects associated with FA consumption.

Fucoidans in Nanomedicine.

Fucoidans are widespread cost-effective sulfated marine polysaccharides which have raised interest in the scientific community over last decades for their wide spectrum of bioactivities. Unsurprisingly, nanomedicine has grasped these compounds to develop innovative therapeutic and diagnostic nanosystems. The applications of fucoidans in nanomedicine as imaging agents, drug carriers or for their intrinsic properties are reviewed here after a short presentation of the main structural data and biological properties of fucoidans. The origin and the physicochemical specifications of fucoidans are summarized in order to discuss the strategy of fucoidan-containing nanosystems in Human health. Currently, there is a need for reproducible, well characterized fucoidan fractions to ensure significant progress.

p-cresol but not p-cresyl sulfate stimulate MCP-1 production via NF-κB p65 in human vascular smooth muscle cells. / p-cresol mas não p-cresil sulfato estimulam a produção de MCP-1 via NF-κB p65 em células vasculares musculares lisas humanas.

INTRODUCTION: p-cresol (PC) and p-cresyl sulfate (PCS) are responsible for many of the uremia clinical consequences, such as atherosclerosis in Chronic Kidney Disease (CKD) patients. OBJECTIVES: We investigate the in vitro impact of PC and PCS on monocyte chemoattractant protein-1 (MCP-1) expression via NF-kappa B (NF-κB) p65 in VSMC. METHODS: PCS was synthesized by PC sulfatation. VSMC were extracted by enzymatic digestion of umbilical cord vein and characterized by immunofluorescence against α-actin antibody. The cells were treated with PC and PCS at their normal (n), uremic (u) and maximum uremic concentrations (m). Cell viability was assessed by MTT. MCP-1 expression was investigated by ELISA in cells supernatants after toxins treatment with or without the NF-κB p65 inhibitor. RESULTS: There was no significant difference in cell viability after toxins treatment for all concentrations tested. There was a significant increase in MCP-1 expression in cells treated with PCu and PCm (p < 0.001) and PCSn, PCSu and PCSm (p < 0.001), compared with the control. When VSMC were treated with the NF-κB p65 inhibitor plus PCu and PCm, there was a significant decrease in MCP-1 production (p < 0.005). This effect was not observed with PCS. CONCLUSIONS: VSMC are involved in atherosclerosis lesion formation and production of MCP-1, which contributes to the inflammatory response initiation. Our results suggest that PC mediates MCP-1 production in VSMC, probably through NF-κB p65 pathway, although we hypothesize that PCS acts through a different subunit pathway since NF-κB p65 inhibitor was not able to inhibit MCP-1 production.

p-cresol mas não p-cresil sulfato estimulam a produção de MCP-1 via NF-κB p65 em células vasculares musculares lisas humanas / p-cresol but not p-cresyl sulfate stimulate MCP-1 production via NF-κB p65 in human vascular smooth muscle cells

RESUMO Introdução: p-cresol (PC) e p-cresil sulfato (PCS) são responsáveis por muitas das consequências clínicas uremia, tais como a aterosclerose em pacientes com Doença Renal Crônica (DRC). Objetivos: No presente trabalho, investigamos in vitro o impacto de PC e PCS na expressão da quimiocina monocyte chemoattractant protein-1 (MCP-1) via NF-kappa B (NF-κB) p65 em VSMC. Métodos: O PCS foi sintetizado por sulfatação do PC. As VSMC foram extraídas por digestão enzimática da veia do cordão umbilical e caracterizadas por imunofluorescência através do anticorpo α-actina. As células foram tratadas com PC e PCS em suas concentrações normal (n), urêmica (u) e urêmica máxima (m). A viabilidade celular foi avaliada pelo ensaio de MTT. A expressão de MCP-1 foi investigada por ELISA em sobrenadantes de células após o tratamento com as toxinas, com ou sem o inibidor de NF-κB p65. Resultados: Não houve diferença significativa na viabilidade das células após o tratamento com toxinas para todas as concentrações testadas. Houve um aumento significativo na expressão de MCP-1 em células tratadas com PCu e PCm (p < 0,001) e PCSn, PCSu e PCSm (p < 0,001), em comparação com o controle. Quando as VSMC foram tratadas com o inibidor de NF-κB p65 mais PCu e PCm, houve uma diminuição significativa na produção de MCP-1 (p < 0,005). Este efeito não foi observado com PCS. Conclusões: VSMC estão envolvidas na formação da lesão aterosclerótica e produção de MCP-1, o que contribui para o início da resposta inflamatória. Os nossos resultados sugerem que a PC medeia a produção de MCP-1 em VSMC, provavelmente através da via NF-κB p65 e que PCS atue através de uma subunidade diferente da via, uma vez que o inibidor da porção p65 não foi capaz de inibir a produção de MCP-1.

ABSTRACT Introduction: p-cresol (PC) and p-cresyl sulfate (PCS) are responsible for many of the uremia clinical consequences, such as atherosclerosis in Chronic Kidney Disease (CKD) patients. Objectives: We investigate the in vitro impact of PC and PCS on monocyte chemoattractant protein-1 (MCP-1) expression via NF-kappa B (NF-κB) p65 in VSMC. Methods: PCS was synthesized by PC sulfatation. VSMC were extracted by enzymatic digestion of umbilical cord vein and characterized by immunofluorescence against α-actin antibody. The cells were treated with PC and PCS at their normal (n), uremic (u) and maximum uremic concentrations (m). Cell viability was assessed by MTT. MCP-1 expression was investigated by ELISA in cells supernatants after toxins treatment with or without the NF-κB p65 inhibitor. Results: There was no significant difference in cell viability after toxins treatment for all concentrations tested. There was a significant increase in MCP-1 expression in cells treated with PCu and PCm (p < 0.001) and PCSn, PCSu and PCSm (p < 0.001), compared with the control. When VSMC were treated with the NF-κB p65 inhibitor plus PCu and PCm, there was a significant decrease in MCP-1 production (p < 0.005). This effect was not observed with PCS. Conclusions: VSMC are involved in atherosclerosis lesion formation and production of MCP-1, which contributes to the inflammatory response initiation. Our results suggest that PC mediates MCP-1 production in VSMC, probably through NF-κB p65 pathway, although we hypothesize that PCS acts through a different subunit pathway since NF-κB p65 inhibitor was not able to inhibit MCP-1 production.

p-Cresyl sulfate suppresses lipopolysaccharide-induced anti-bacterial immune responses in murine macrophages in vitro.

p-Cresyl sulfate (pCS) is a known uremic toxin that is metabolized from p-cresol produced by intestinal bacteria. Abnormal accumulation of pCS in the blood is a characteristic of chronic kidney disease (CKD). pCS is suggested to cause immune dysfunction and increase the risk of infectious diseases in CKD patients. In this study, we focused on the effects of pCS on macrophage functions related to host defense. We evaluated the effects of pCS on cytokine production, nitric oxide (NO) production, arginase activity, expression of cell-surface molecules, and phagocytosis in the macrophage-like cell line, RAW264.7. pCS significantly decreased interleukin (IL)-12 p40 production and increased IL-10 production. pCS also decreased NO production, but did not influence arginase activity. pCS suppressed lipopolysaccharide-induced CD40 expression on the cell surface, but did not influence phagocytosis. We further assessed whether the effects of pCS observed in the macrophage-like cell line were consistent in primary macrophages. Similar to RAW264.7 cells, pCS decreased IL-12 p40 and p70 production and increased IL-10 production in primary peritoneal macrophages. These data indicate that pCS suppresses certain macrophage functions that contribute to host defense, and may play a role in CKD-related immune dysfunction.

Novel Polyanions Inhibiting Replication of Influenza Viruses.

Novel sulfonated derivatives of poly(allylamine hydrochloride) (NSPAHs) and N-sulfonated chitosan (NSCH) have been synthesized, and their activity against influenza A and B viruses has been studied and compared with that of a series of carrageenans, marine polysaccharides of well-documented anti-influenza activity. NSPAHs were found to be nontoxic and very soluble in water, in contrast to gel-forming and thus generally poorly soluble carrageenans.In vitroandex vivostudies using susceptible cells (Madin-Darby canine kidney epithelial cells and fully differentiated human airway epithelial cultures) demonstrated the antiviral effectiveness of NSPAHs. The activity of NSPAHs was proportional to the molecular mass of the chain and the degree of substitution of amino groups with sulfonate groups. Mechanistic studies showed that the NSPAHs and carrageenans inhibit influenza A and B virus assembly in the cell.