laminaran and Disease-Models--Animal

We previously reported medicinal chemistry efforts that identified MK-5204, an orally efficacious β-1,3-glucan synthesis inhibitor derived from the natural product enfumafungin. Further extensive optimization of the C2 triazole substituent identified 4-pyridyl as the preferred replacement for the carboxamide of MK-5204, leading to improvements in antifungal activity in the presence of serum, and increased oral exposure. Reoptimizing the aminoether at C3 in the presence of this newly discovered C2 substituent, confirmed that the (R) t-butyl, methyl aminoether of MK-5204 provided the best balance of these two key parameters, culminating in the discovery of ibrexafungerp, which is currently in phase III clinical trials. Ibrexafungerp displayed significantly improved oral efficacy in murine infection models, making it a superior candidate for clinical development as an oral treatment for Candida and Aspergillus infections.

Topics: Administration, Oral; Animals; Antifungal Agents; Aspergillosis; Aspergillus; beta-Glucans; Candida albicans; Candidiasis; Disease Models, Animal; Glycosides; Half-Life; Mice; Structure-Activity Relationship; Triterpenes

Our previously reported efforts to produce an orally active β-1,3-glucan synthesis inhibitor through the semi-synthetic modification of enfumafungin focused on replacing the C2 acetoxy moiety with an aminotetrazole and the C3 glycoside with a N,N-dimethylaminoether moiety. This work details further optimization of the C2 heterocyclic substituent, which identified 3-carboxamide-1,2,4-triazole as a replacement for the aminotetrazole with comparable antifungal activity. Alkylation of either the carboxamidetriazole at C2 or the aminoether at C3 failed to significantly improve oral efficacy. However, replacement of the isopropyl alpha amino substituent with a t-butyl, improved oral exposure while maintaining antifungal activity. These two structural modifications produced MK-5204, which demonstrated broad spectrum activity against Candida species and robust oral efficacy in a murine model of disseminated Candidiasis without the N-dealkylation liability observed for the previous lead.

Topics: Administration, Oral; Animals; Antifungal Agents; beta-Glucans; Candida; Candidiasis; Disease Models, Animal; Glucosyltransferases; Glycosides; Half-Life; Mice; Microbial Sensitivity Tests; Stereoisomerism; Structure-Activity Relationship; Triazoles; Triterpenes

Chronic stress elevates the cortisol beyond normal levels, which affects cognition including learning & memory. This injurious effect is primarily mediated via over excitation of metabotropic glucocorticoid receptors (mGR).. The present study was aimed to appraise the neuroprotective effects of naturally occurring molecule β-1,3-glucan by interfering with stress-cortisol-mGR axis. Our data of virtual screening (in silico) exhibited the promising interactions of β-glucan with the mGR. Therefore, the study was extended to evaluate its efficacy (2.5, 5 and 10 mg/kg/ i.p) in an animal model of chronic unpredictable mild stress (CUMS, 28 days) induced memory impairment.. Results of the current study revealed the β-glucan provided dose dependent protection against deleterious effects of stress on learning and memory associated parameters observed in Morris water maze (MWM) task. At higher tested doses, it has also significantly antagonized the stress induced weight loss and corticosterone elevation.

Topics: Animals; beta-Glucans; Cognitive Dysfunction; Corticosterone; Disease Models, Animal; Glucans; Hippocampus; Maze Learning; Rodentia; Stress, Psychological

Transient brain ischemia triggers selective neuronal death/loss, especially in vulnerable regions of the brain including the hippocampus. Laminarin, a polysaccharide originating from brown seaweed, has various pharmaceutical properties including an antioxidant function. To the best of our knowledge, few studies have been conducted on the protective effects of laminarin against ischemic injury induced by ischemic insults. In this study, we histopathologically investigated the neuroprotective effects of laminarin in the Cornu Ammonis 1 (CA1) field of the hippocampus, which is very vulnerable to ischemia-reperfusion injury, following transient forebrain ischemia (TFI) for five minutes in gerbils. The neuroprotective effect was examined by cresyl violet staining, Fluoro-Jade B histofluorescence staining and immunohistochemistry for neuronal-specific nuclear protein. Additionally, to study gliosis (glial changes), we performed immunohistochemistry for glial fibrillary acidic protein to examine astrocytes, and ionized calcium-binding adaptor molecule 1 to examine microglia. Furthermore, we examined alterations in pro-inflammatory M1 microglia by using double immunofluorescence. Pretreatment with 10 mg/kg laminarin failed to protect neurons in the hippocampal CA1 field and did not attenuate reactive gliosis in the field following TFI. In contrast, pretreatment with 50 or 100 mg/kg laminarin protected neurons, attenuated reactive gliosis and reduced pro-inflammatory M1 microglia in the CA1 field following TFI. Based on these results, we firmly propose that 50 mg/kg laminarin can be strategically applied to develop a preventative against injuries following cerebral ischemic insults.

Topics: Animals; Brain Ischemia; Disease Models, Animal; Gerbillinae; Gliosis; Glucans; Hippocampus; Immunohistochemistry; Neuroprotective Agents; Pyramidal Cells

Adipose-derived stem cells (ADSCs) have anti-inflammatory and regenerative properties. The purpose of this study was to investigate the effect of locally administered ADSCs in a rheumatoid arthritis (RA) mouse model. In an in vivo experiment, single-cell ADSCs and three dimensionally-cultured ADSC spheroids were injected intra-articularly into the knees of RA model mice and histologically assessed. Marked improvement of synovial inflammation and articular cartilage regeneration was found in ADSC-treated mice. Proliferation, migration, and apoptosis assays of synovial fibroblasts incubated with single-cell and spheroid ADSCs were performed. The expression levels of total cytokine RNA in ADSC single cells, spheroids, and ADSC-treated inflammatory synovial fibroblasts were also evaluated by quantitative reverse transcription PCR. ADSCs suppressed the proliferation and migration of activated inflammatory cells and downregulated inflammatory cytokines. TSG-6 and TGFβ1 were significantly upregulated in ADSCs compared to controls and TGFβ1 was significantly upregulated in ADSC spheroids compared to single cells. The apoptosis rate of ADSC spheroids was significantly lower than that of single-cell ADSCs. These results indicated that intra-articular administration of ADSC single cells and spheroids was effective in an RA mouse model, offering a novel approach for the development of effective localized treatments for patients with RA.

Topics: Adipose Tissue; Animals; Arthritis, Rheumatoid; Cartilage, Articular; Cell Adhesion Molecules; Cell Movement; Cell Proliferation; Disease Models, Animal; Female; Fibroblasts; Glucans; Inflammation; Macrophages; Mice, Inbred BALB C; Regeneration; Spheroids, Cellular; Stem Cell Transplantation; Synovial Membrane; Transforming Growth Factor beta1; Up-Regulation

Laminarin is a polysaccharide isolated from brown algae that has various biological and pharmacological activities, such as antioxidant and anti-inflammatory properties. We recently reported that pretreated laminarin exerted neuroprotection against transient forebrain ischemia/reperfusion (IR) injury when we pretreated with 50 mg/kg of laminarin once a day for seven days in adult gerbils. However, there have been no studies regarding a neuroprotective effect of pretreated laminarin against IR injury in aged animals and its related mechanisms. Therefore, in this study, we intraperitoneally inject laminarin (50 mg/kg) once a day to aged gerbils for seven days before IR (5-min transient ischemia) surgery and examine the neuroprotective effect of laminarin treatment and the mechanisms in the gerbil hippocampus. IR injury in vehicle-treated gerbils causes loss (death) of pyramidal neurons in the hippocampal CA1 field at five days post-IR. Pretreatment with laminarin effectively protects the CA1 pyramidal neurons from IR injury. Regarding the laminarin-treated gerbils, production of superoxide anions, 4-hydroxy-2-nonenal expression and pro-inflammatory cytokines [interleukin(IL)-1β and tumor necrosis factor-α] expressions are significantly decreased in the CA1 pyramidal neurons after IR. Additionally, laminarin treatment significantly increases expressions of superoxide dismutase and anti-inflammatory cytokines (IL-4 and IL-13) in the CA1 pyramidal neurons before and after IR. Taken together, these findings indicate that laminarin can protect neurons from ischemic brain injury in an aged population by attenuating IR-induced oxidative stress and neuroinflammation.

Topics: Animals; Brain Ischemia; Cytokines; Disease Models, Animal; Gerbillinae; Glucans; Hippocampus; Inflammation; Male; Nerve Tissue Proteins; Neurons; Neuroprotection; Neuroprotective Agents; Oxidative Stress; Reperfusion Injury; Superoxide Dismutase

This study examined the effects of dietary supplementation with laminarin or chitosan on colonic health in pigs challenged with dextran sodium sulphate (DSS). Weaned pigs were assigned to: (1) a basal diet (n = 22); (2) a basal diet + laminarin (n = 10); and (3) a basal diet + chitosan (n = 10). On d35, the basal group was split, creating four groups: (1) the basal diet (control); (2) the basal diet + DSS; (3) the basal diet + laminarin + DSS; and (4) the basal diet + chitosan + DSS. From d39-42, the pigs were orally challenged with DSS. On d44, colonic tissue/digesta samples were collected. The basal DSS group had reduced growth, higher pathology score and an increased expression of

Topics: Animals; Chitosan; Colitis; Dextrans; Dietary Supplements; Disease Models, Animal; Glucans; Intestinal Mucosa; Male; Polysaccharides; Protective Agents; Random Allocation; Swine

The Cek1 MAP kinase (MAPK) mediates vegetative growth and cell wall biogenesis in the fungal pathogen Candida albicans. Alterations in the fungal cell wall caused by a defective Cek1‑mediated signaling pathway leads to increased β‑1,3‑glucan exposure influencing dectin‑1 fungal recognition by immune cells. We show here that cek1 cells also display an increased exposure of α‑1,2 and β‑1,2‑mannosides (α‑M and β‑M), a phenotype shared by strains defective in the activating MAPKK Hst7, suggesting a general defect in cell wall assembly. cek1 cells display walls with loosely bound material as revealed by transmission electron microscopy and are sensitive to tunicamycin, an inhibitor of N‑glycosylation. Transcriptomal analysis of tunicamycin treated cells revealed a differential pattern between cek1 and wild type cells which involved mainly cell wall and stress related genes. Mapping α‑M and β‑M epitopes in the mannoproteins of different cell wall fractions (CWMP) revealed an important shift in the molecular weight of the mannan derived from mutants defective in this MAPK pathway. We have also assessed the role of galectin‑3, a member of a β‑galactoside‑binding protein family shown to bind to and kill C. albicans through β‑M recognition, in the infection caused by cek1 mutants. Increased binding of cek1 to murine macrophages was shown to be partially blocked by lactose. Galectin-3(-/-) mice showed increased resistance to fungal infection, although galectin-3 did not account for the reduced virulence of cek1 mutants in a mouse model of systemic infection. All these data support a role for the Cek1‑mediated pathway in fungal cell wall maintenance, virulence and antifungal discovery.

Topics: Animals; beta-Glucans; Candida albicans; Candidiasis; Cell Wall; Disease Models, Animal; Fungal Proteins; Galectin 3; Gene Expression Profiling; Gene Expression Regulation, Fungal; Mannosides; MAP Kinase Signaling System; Mice; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinases; Mutation; Tunicamycin; Virulence

β-glucans, which can activate innate immune responses, are a major component in the cell wall of the cyst form of Pneumocystis In the current study, we examined whether β-1,3-glucans are masked by surface proteins in Pneumocystis and what role β-glucans play in Pneumocystis-associated inflammation. For 3 species, including Pneumocystis jirovecii, which causes Pneumocystis pneumonia in humans, Pneumocystis carinii, and Pneumocystis murina, β-1,3-glucans were masked in most organisms, as demonstrated by increased exposure following trypsin treatment. Using quantitative polymerase chain reaction and microarray techniques, we demonstrated in a mouse model of Pneumocystis pneumonia that treatment with caspofungin, an inhibitor of β-1,3-glucan synthesis, for 21 days decreased expression of a broad panel of inflammatory markers, including interferon γ, tumor necrosis factor α, interleukin 1β, interleukin 6, and multiple chemokines/chemokine ligands. Thus, β-glucans in Pneumocystis cysts are largely masked, which likely decreases innate immune activation; this mechanism presumably was developed for interactions with immunocompetent hosts, in whom organism loads are substantially lower. In immunosuppressed hosts with a high organism burden, organism death and release of glucans appears to be an important contributor to deleterious host inflammatory responses.

Topics: Animals; Antifungal Agents; beta-Glucans; Caspofungin; Cytokines; Disease Models, Animal; Echinocandins; Lipopeptides; Mice, Knockout; Microarray Analysis; Pneumocystis; Pneumonia; Pneumonia, Pneumocystis; Real-Time Polymerase Chain Reaction

Aspergillus fumigatus is a fungal pathogen that is capable of adapting to different host niches and to avoid host defenses. An enhanced understanding of how, and which, A. fumigatus signal transduction pathways are engaged in the regulation of these processes is essential for the development of improved disease control strategies. Protein phosphatases are central to numerous signal transduction pathways. To comprehend the functions of protein phosphatases in A. fumigatus, 32 phosphatase catalytic subunit encoding genes were identified. We have recognized PtcB as one of the phosphatases involved in the high osmolarity glycerol response (HOG) pathway. The ΔptcB mutant has both increased phosphorylation of the p38 MAPK (SakA) and expression of osmo-dependent genes. The ΔptcB strain was more sensitive to cell wall damaging agents, had increased chitin and β-1,3-glucan, and impaired biofilm formation. The ΔptcB strain was avirulent in a murine model of invasive pulmonary aspergillosis. These results stress the importance of the HOG pathway in the regulation of pathogenicity determinants and virulence in A. fumigatus.

Topics: Animals; Aspergillus fumigatus; beta-Glucans; Biofilms; Cell Wall; Chitin; Computational Biology; Disease Models, Animal; Fungal Proteins; Gene Expression Regulation, Fungal; Glycerol; Mice; Mutation; Osmolar Concentration; Phosphoric Monoester Hydrolases; Signal Transduction

Infection and inflammation suppress the expression and activity of several drug transporters in liver. In the intestine, P-glycoprotein (P-gp/MDR1), multidrug resistance-associated protein 2 (MRP2), and breast cancer resistance protein (BCRP) are important barriers to the absorption of many clinically important drugs. The expression and activity of these proteins were examined under inflammation. Drug transport was determined in jejunum and ileum segments isolated from 1.0 mg/kg, 5.0 mg/kg, and 7.5 mg/kg indomethacin-treated or control rats in diffusion chambers. Transport of laminaran, used as a model compound of (1-3) β-D-glucan, was measured for 120 min in the presence or absence of inhibitors. Reverse transcription-polymerase chain reaction was used to measure mRNA levels. Compared with controls, levels of Mdr1a mRNA were significantly decreased in the jejunum and ileum of 7.5 mg/kg indomethacin-treated rats. Both reductions in the basolateral to apical efflux of laminaran and increases in the apical to basolateral influx of laminaran were observed, resulting in significant increases in the apical to basolateral absorption of laminaran in 7.5 mg/kg indomethacin-treated rats. The inhibitory effect of verapamil on laminaran transport was observed in control rats but not in indomethacin-treated rats. Fluorescein isothiocyanate dextran 40,000 permeability, membrane resistance, and claudin-4 mRNA level were not altered, indicating no change in the paracellular pathway. These results indicate that indomethacin-induced inflammation reduces the intestinal expression and activity of P-gp in rats, which elicits corresponding changes in the intestinal transport of laminaran. Hence, inflammatory diseases may impose variability in drug bioavailability through alterations in the intestinal expression and activity of drug transporters.

Topics: Animals; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily G, Member 2; ATP-Binding Cassette Transporters; beta-Glucans; Biological Transport; Disease Models, Animal; Down-Regulation; Glucans; Ileum; Indomethacin; Inflammation; Intestinal Absorption; Jejunum; Male; Proteoglycans; Rats, Wistar; RNA, Messenger; Time Factors

Spondyloarthritides (SpA) occur in 1% of the population and include ankylosing spondylitis (AS) and arthropathy of inflammatory bowel disease (IBD), with characteristic spondylitis, arthritis, enthesitis, and IBD. Genetic studies implicate interleukin-23 (IL-23) receptor signaling in the development of SpA and IBD, and IL-23 overexpression in mice is sufficient for enthesitis, driven by entheseal-resident T cells. However, in genetically prone individuals, it is not clear where IL-23 is produced and how it drives the SpA syndrome, including IBD or subclinical gut inflammation of AS. Moreover, it is unclear why specific tissue involvement varies between patients with SpA. We undertook this study to determine the location of IL-23 production and its role in SpA pathogenesis in BALB/c ZAP-70(W163C)-mutant (SKG) mice injected intraperitoneally with β-1,3-glucan (curdlan).. Eight weeks after curdlan injection in wild-type or IL-17A(-/-) SKG or BALB/c mice, pathology was scored in tissue sections. Mice were treated with anti-IL-23 or anti-IL-22. Cytokine production and endoplasmic reticulum (ER) stress were determined in affected organs.. In curdlan-treated SKG mice, arthritis, enthesitis, and ileitis were IL-23 dependent. Enthesitis was specifically dependent on IL-17A and IL-22. IL-23 was induced in the ileum, where it amplified ER stress, goblet cell dysfunction, and proinflammatory cytokine production. IL-17A was pathogenic, while IL-22 was protective against ileitis. IL-22+CD3- innate-like cells were increased in lamina propria mononuclear cells of ileitis-resistant BALB/c mice, which developed ileitis after curdlan injection and anti-IL-22.. In response to systemic β-1,3-glucan, intestinal IL-23 provokes local mucosal dysregulation and cytokines driving the SpA syndrome, including IL-17/IL-22-dependent enthesitis. Innate IL-22 production promotes ileal tolerance.

Topics: Animals; Antibodies; beta-Glucans; Disease Models, Animal; Endoplasmic Reticulum Stress; Female; Ileitis; Immune Tolerance; Interleukin-17; Interleukin-22; Interleukin-23 Subunit p19; Interleukins; Intestinal Mucosa; Intestines; Male; Mice; Mice, Inbred BALB C; Mice, Knockout; Receptors, Interleukin; Spondylarthritis

The application of the phagocytic receptor agonists in cancer immunotherapy was studied. Agonists (laminarin, molecules with terminal mannose, N-Formyl-methioninyl-leucyl-phenylalanine) were firmly anchored to the tumor cell surface. When particular agonists of phagocytic receptors were used together with LPS (Toll-like receptor agonist), high synergy causing tumour shrinkage and a temporary or permanent disappearance was observed. Methods of anchoring phagocytic receptor agonists (charge interactions, anchoring based on hydrophobic chains, covalent bonds) and various regimes of phagocytic agonist/LPS mixture applications were tested to achieve maximum therapeutic effect. Combinations of mannan/LPS and f-MLF/LPS (hydrophobic anchors) in appropriate (pulse) regimes resulted in an 80% and 60% recovery for mice, respectively. We propose that substantial synergy between agonists of phagocytic and Toll-like receptors (TLR) is based on two events. The TLR ligand induces early and massive inflammatory infiltration of tumors. The effect of this cell infiltrate is directed towards tumor cells, bearing agonists of phagocytic receptors on their surface. The result of these processes was effective killing of tumor cells. This novel approach represents exploitation of innate immunity mechanisms for treating cancer.

Topics: Animals; Cell Proliferation; Cytokines; Disease Models, Animal; Flow Cytometry; Glucans; Immunotherapy; Ligands; Lipopolysaccharides; Macrophage Activation; Mannose; Melanoma, Experimental; Mice; Mice, Inbred C57BL; Polysaccharides; Receptors, Immunologic; Signal Transduction; Survival Analysis; Toll-Like Receptors

RNA interference therapy utilizes physiological gene silencing that is originally found as a defense function against foreign RNAs. To silence the target gene, short double stranded RNA has to be delivered to cytosol. However, lack of a suitable delivering carrier is the major obstacle to practical usage. In this study, we present a novel complex consisting of β-1,3-glucan and short interference RNA (siRNA) as a solution for the problem. We used a β-1,3-glucan schizophyllan (SPG) and a siRNA (dA-siTNFα) that is designed to suppress tumor necrosis factor alpha (TNF-α), where the sense strand of siRNA has (dA(40)) tail to induce complexation with SPG. The dA-siTNFα/SPG complex showed higher affinity to recombinant dectin-1 than SPG itself, where dectin-1 is a β-1,3-glucan receptor expressed on antigen presenting cells and can be a target for specific delivery. The complex suppressed lipopolysaccharide (LPS)-induced TNF-α secretion by peritoneal macrophages in vitro. When the complex was intravenously injected, the oligonucleotide accumulated in liver; especially distributed into Kupffer cells. The complex significantly decreased the serum TNF-α level for the mouse model of LPS-induced acute hepatitis. This new siRNA delivery system may overcome the problem for RNA interference therapy because of its non-toxicity and high target specificity.

Topics: Acute Disease; Animals; beta-Glucans; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Hepatitis; Lipopolysaccharides; Macrophages; Mice; Mice, Inbred C57BL; RNA, Small Interfering; Structure-Activity Relationship; Tissue Distribution; Tumor Necrosis Factor-alpha

To determine the impact of β-1,3-glucan isolated from Euglena gracilis on corneal epithelial cell migration and on wound healing in a rat alkali burn model.. Immortalized human corneal epithelial cells (HCECs) were cultured in media with 50, 100 and 200 μg/mL laminarin (β-1,3- and β-1,6-glucans), β-1,3-glucan and hyaluronic acid (HA)-conjugated β-1,3-glucan; Dulbecco's modified Eagle's medium (DMEM)/nutrient mixture F-12 (negative control) and serum containing DMEM/nutrient mixture F-12 (positive control). Migration assays were conducted via the manual scraping of HCECs. Next, alkali injuries were induced using 1 N NaOH in 40 eyes of 40 Sprague-Dawley male rats. The injury-only group (n = 10) received topical phosphate-buffered saline four times a day for 2 d. The study groups received 200 μg/mL topical laminarin (n = 10), β-1,3-glucan (n = 10) and β-1,3-glucan HA (n = 10). Using slit-lamp biomicroscopy, injured corneas were evaluated in terms of re-epithelialization and opacity, and tissue sections were histologically analyzed.. Migration assay rates were enhanced as laminarin and β-1,3-glucan increased, compared to negative control cells (all p < 0.05). In the comparison between β-1,3-glucan and its HA conjugate form, β-1,3-glucan-HA showed more enhanced migration rate than β-1,3-glucan (p < 0.05). In rat alkali burn model, wound-healing ratio was greatest in β-1,3-glucan-HA groups (96.0 ± 4.1%), followed by β-1,3-glucan (86.0 ± 6.5%), laminarin (67.0 ± 7.5%) and injury-only group (54.0 ± 6.5%) (p < 0.0001; ANOVA). The opacity score was also lowest in β-1,3-glucan-HA groups (3.0 ± 0.75), followed by β-1,3-glucan (3.4 ± 0.5), laminarin (3.7 ± 0.8) and injury-only group (4.7 ± 0.46) (p < 0.0001; ANOVA) Histologically, relatively fewer polymorphonuclear leukocytes infiltrated the corneal stroma in the β-1,3-glucan and β-1,3-glucan-HA groups, compared to the injury-only group.. β-1,3-Glucan, particularly when conjugated with HA, promoted epithelial wound healing in vitro and suppressed the acute inflammatory reaction in corneal alkali burns.

Topics: Adjuvants, Immunologic; Alkalies; Animals; beta-Glucans; Burns, Chemical; Cell Line, Transformed; Cell Movement; Corneal Opacity; Disease Models, Animal; Epithelium, Corneal; Euglena gracilis; Eye Burns; Humans; Male; Rats; Rats, Sprague-Dawley; Wound Healing

Previous studies associate lipid peroxidation with long-term memory (LTM) failure in a gastropod model (Lymnaea stagnalis) of associative learning and memory. This process involves activation of Phospholipase A2 (PLA2), an enzyme mediating the release of fatty acids such as arachidonic acid that form the precursor for a variety of pro-inflammatory lipid metabolites. This study investigated the effect of biologically realistic challenges of L. stagnalis host defense response system on LTM function and potential involvement of PLA2, COX and LOX therein.. Systemic immune challenges by means of β-glucan laminarin injections induced elevated H2O2 release from L. stagnalis circulatory immune cells within 3 hrs of treatment. This effect dissipated within 24 hrs after treatment. Laminarin exposure has no direct effect on neuronal activity. Laminarin injections disrupted LTM formation if training followed within 1 hr after injection but had no behavioural impact if training started 24 hrs after treatment. Intermediate term memory was not affected by laminarin injection. Chemosensory and motor functions underpinning the feeding response involved in this learning model were not affected by laminarin injection. Laminarin's suppression of LTM induction was reversed by treatment with aristolochic acid, a PLA2 inhibitor, or indomethacin, a putative COX inhibitor, but not by treatment with nordihydro-guaiaretic acid, a putative LOX inhibitor.. A systemic immune challenge administered shortly before behavioural training impairs associative LTM function in our model that can be countered with putative inhibitors of PLA2 and COX, but not LOX. As such, this study establishes a mechanistic link between the state of activity of this gastropod's innate immune system and higher order nervous system function. Our findings underwrite the rapidly expanding view of neuroinflammatory processes as a fundamental, evolutionary conserved cause of cognitive and other nervous system disorders.

Topics: Analysis of Variance; Animals; Cerebral Cortex; Conditioning, Psychological; Disease Models, Animal; Enzyme Inhibitors; Glucans; Hemocytes; Hydrogen Peroxide; Hypolipidemic Agents; Immunity, Innate; Indomethacin; Long-Term Potentiation; Lymnaea; Memory Disorders; Neurons; Phospholipases A2; Polysaccharides; Prostaglandin-Endoperoxide Synthases; Time Factors

Zymosan was hydrolysed with HCl and fractionated by ultrafiltration and dialysis to obtain water-soluble fragments A, B and C. Physical and chemical analyses showed that these fractions are composed primarily of glucose and have molecular weights of 8 kDa, 5 kDa and 2 kDa, respectively. A glycosidic linkage analysis indicated that they are mainly composed of β-1,3-glucans. Fragment A, which has the highest molecular weight, contains approximately 30% β-1,6-linked glucans, but fragment C is almost entirely composed of linear β-1,3-glucan chains. The anti-chronic atrophic gastritis activity experiments showed that fragment A has significant activity, the activity of zymosan is quite low and the activities of fragments B and C are in between those of fragment A and zymosan.

Topics: Animals; beta-Glucans; Bile; Chromatography, Gel; Chronic Disease; Disease Models, Animal; Gastric Mucosa; Gastritis, Atrophic; Immunization; Inflammation; Molecular Weight; Rats; Rats, Wistar; Swine; Zymosan

In this study we demonstrated that the oral administration of β-1,3-glucan (Imunoglucan®) protects mice from a lethal dose of Listeria monocytogenes (LM) when administered prophylactically for 10 days at the doses of 150 and 300 mg/kg, with survival rates up to 40%. These doses also prevented the myelosuppression and the splenomegaly caused by a sublethal infection with LM, due to increased numbers of granulocyte-macrophage progenitors (CFU-GM) in the bone marrow. Investigation of the production of colony-stimulating factors revealed an increased colony-stimulating activity (CSA) in the serum of infected mice pre-treated with Imunoglucan®. The treatment also restored the reduced ability of stromal cells to display myeloid progenitors in long-term bone marrow cultures (LTBMC) and up-regulated IL-6 and IL-1α production by these cells in the infected mice, which was consistent with higher number of non-adherent cells. Additional studies to investigate the levels of interferon-gamma (INF-γ) in the supernatant of splenocyte cultures demonstrated a further increase in the level of this cytokine in infected-treated mice, compared to infected controls. In all cases, no differences were observed between the responses of the two optimal biologically effective doses. In contrast, no significant changes were produced by the treatment with the 50mg/kg dose. In addition, no changes were observed in normal mice treated with the three doses used. All together our results suggest that orally given Imunoglucan® indirectly modulates immune activity and probably disengages Listeria induced suppression of these responses by inducing a higher reserve of myeloid progenitors in the bone marrow in consequence of biologically active cytokine release (CSFs, IL-1α, IL-6, and INF-γ).

Topics: Adjuvants, Immunologic; Administration, Oral; Animals; beta-Glucans; Bone Marrow Cells; Cell Culture Techniques; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Granulocyte-Macrophage Colony-Stimulating Factor; Granulocyte-Macrophage Progenitor Cells; Hematopoiesis; Hematopoietic Stem Cells; Interferon-gamma; Interleukin-1alpha; Interleukin-6; Listeria monocytogenes; Listeriosis; Male; Mice; Mice, Inbred BALB C; Splenomegaly

We investigated the effects and mechanisms by which FTY720 (FTY) inhibits arthritis development in the SKG mouse rheumatoid arthritis (RA) model. FTY (1mg/kg/day) administration suppressed the progression of laminarin-induced arthritis in SKG mice. FTY treatment decreased IL-6 and TNF-alpha expression in synovial fibroblast cells and the number of inflammatory cells overall. Bone destruction was also suppressed by treatment with FTY. The numbers of CD4(+) and CD8(+) T cells were significantly increased in the thymus and decreased in the spleen in FTY-treated SKG mice. FTY enhanced IL-4 production by CD4(+) T cells stimulated by allogeneic spleen cells and inhibited prostaglandin E(2) (PGE(2)) production by a TNF-alpha-stimulated synovial fibroblast cell line. These results indicate that FTY can inhibit arthritis in SKG mice via sequestration of autoimmune CD4(+) T cells in the thymus, enhancement of Th2 immune responses, and inhibition of PGE(2) production by synovial cells.

Topics: Administration, Oral; Animals; Arthritis, Rheumatoid; CD4-Positive T-Lymphocytes; Cell Line; Cytokines; Dinoprostone; Disease Models, Animal; Female; Fingolimod Hydrochloride; Glucans; Humans; Immunosuppressive Agents; Interleukin-4; Mice; Mice, Inbred Strains; Polysaccharides; Propylene Glycols; Specific Pathogen-Free Organisms; Sphingosine; Spleen; Thymus Gland

Leukocyte extravasation is initiated by an interaction of selectin adhesion molecules and appropriate carbohydrate ligands. Targeting those interactions seems a promising approach to treat chronic inflammation. We developed a beta-1, 3-glucan sulfate (PS3) with inhibitory activity toward L and P-selectins under static conditions. Here, detailed investigation showed inhibition of P- and L-selectins, but not E-selectin under flow conditions (relative reduction of interaction with appropriate ligands to 34.4+/-16.6, 8.5+/-3.6, or 99.5+/-9.9%, respectively, by PS3 for P-, L- or E-selectin). Intravital microscopy revealed reduction of leukocyte rolling in skin microvasculature from 22.7+/-5.0 to 12.6+/-4.0% after injection of PS3. In the next experiments, mice were sensitized with 2,4,-dinitrofluorobenzene (DNFB), and lymphocytes were transferred into syngeneic recipients, which were challenged by DNFB. Inflammatory responses were reduced when immunity was generated in mice treated with PS3 or in L-selectin-deficient mice. No effect was observed when L-selectin-deficient donor mice were treated with PS3, further suggesting that PS3 acted primarily through inhibition of L-selectin. Elicitation of a contact hypersensitivity response was reduced in P-selectin-deficient and in PS3-treated mice. Again, PS3 had no effect in P-selectin-deficient mice. PS3 is a potent P- and L-selectin inhibitor that may add to the therapy of inflammatory diseases.

Topics: Adoptive Transfer; Allergens; Animals; beta-Glucans; Cell Communication; Cells, Cultured; Dermatitis, Contact; Dinitrofluorobenzene; Disease Models, Animal; Endothelium, Vascular; Glucans; Humans; L-Selectin; Leukocytes, Mononuclear; Male; Mice; Mice, Inbred C57BL; P-Selectin

Experience with anidulafungin against Candida krusei is limited. Immunosuppressed mice were injected with 1.3 x 10(7) to 1.5 x 10(7) CFU of C. krusei. Animals were treated with saline, 40 mg/kg fluconazole, 1 mg/kg amphotericin B, or 10 and 20 mg/kg anidulafungin for 5 days. Anidulafungin improved survival and significantly reduced the number of CFU/g in kidneys and serum beta-glucan levels.

Topics: Anidulafungin; Animals; Antifungal Agents; beta-Glucans; Candida; Candidiasis; Disease Models, Animal; Echinocandins; Kidney; Male; Mice

Biofilms are microbial communities that are associated with solid surfaces such as intravascular catheters. Candida species are a major cause of medical device-associated infections. Twenty percent to 70% of all candidemias are associated with this biofilm process. Diagnosis and effective treatment of Candida device-associated infections requires removal of the involved device. The ability to identify a biofilm device infection before catheter removal may obviate removal of a substantial number of devices. Prior studies in our laboratory identified cell wall changes (specifically, increased beta -1,3 glucan) associated with biofilm, compared with planktonic C. albicans. Both in vitro and in vivo (catheter) biofilm models were used to determine whether biofilm cells secreted more beta -1,3 glucan and whether these differences could be used to discern the presence of a Candida biofilm infection with 3 species (C. albicans, C. glabrata, and C. parapsilosis). A limulus lysate assay was used to quantify beta -1,3 glucan in supernatants from planktonic or biofilm cultures and in the serum of rats with an intravascular catheter biofilm infection or disseminated candidiasis. beta -1,3 glucan was detected from both in vitro and in vivo models from each condition. However, the concentrations of beta -1,3 glucan from the biofilm conditions were 4-10-fold greater in vitro (P<.001) and were 10-fold greater in vivo (P<.001), despite equal or fewer numbers of cells in the biofilm conditions. These results suggest the secreted polysaccharide beta -1,3 glucan may serve as a useful tool for the diagnosis of Candida biofilm and device-associated infections.

Topics: Animals; beta-Glucans; Biofilms; Candida; Candida albicans; Candida glabrata; Candidiasis; Catheterization, Central Venous; Disease Models, Animal; Humans; Limulus Test; Microscopy, Confocal; Rats

Beta-1,3-glucans enhance immune reactions such as antitumor, antibacterial, antiviral, anticoagulatory, and wound healing activities. beta-1,3-Glucans have various functions depending on the molecular weight, degree of branching, conformation, water solubility, and intermolecular association. The molecular weight of the soluble glucan was about 15,000 as determined by a high-performance size exclusion chromatography. From the infrared (IR) and 13C NMR analytical data, the purified soluble glucan was found to exclusively consist of beta-D-glucopyranose with 1,3 linkage. We tested the immunestimulating activities of the soluble beta-1,3-glucan extracted from Agrobacterium sp. R259 KCTC 1019 and confirmed the following activities. IFN-gamma and each cytokines were induced in the spleens and thymus of mice treated with soluble beta-1,3-glucan. Adjuvant effect was observed on antibody production. Nitric oxide was synthesized in monocytic cell lines treated with beta-1,3-glucan. The cytotoxic and antitumor effects were observed on various cancer cell lines and ICR mice. These results strongly suggested that this soluble beta-1,3-glucan could be a good candidate for an immune-modulating agent.

Topics: Animals; Antineoplastic Agents; beta-Glucans; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Magnetic Resonance Spectroscopy; Mice; Mice, Inbred ICR; Neoplasm Metastasis; Rhizobium; Solubility; Water

The recent events increasing the threat of bioterrorism have prompted a widespread search for defenses against this peril.. To evaluate the anthrax-protective effect of beta1,3-glucan immune modulators (PGG-glucan and WGP beta glucan) in an experimental animal model.. Beta1,3-glucan immune modulators were administered by subcutaneous injection to Balb/c mice 2 days prior to anthrax challenge. WGP beta glucan was administered by daily oral gavage for 7 days prior to challenge, or in drinking water for 10 days postchallenge with a lethal dose of Bacillus anthracis spores. Survival, survival time, and microbial bioburden relative to an infected, untreated control group were assessed.. A single injected dose of PGG-glucan or WGP beta glucan immune modulators given 2 days before challenge significantly: (a) increased the survival rate of infected mice (2.5-fold), (b) diminished the bacterial load in the lungs of infected mice (4-8-fold), and (c) increased the proportion of bacteria-free animals 10 days after challenge (2-fold). In mice prophylactically administered oral WGP beta glucan for 1 week prior to infection, survival increased from 50% to 100%; therapeutic administration of oral WGP beta glucan for 10 days postinfection increased survival from 30% up to 90% in treatment groups.. These results demonstrate the potential for beta1,3-glucan immune modulators to provide a significant degree of protection against anthrax, a potential biological warfare (BW) agent in a mouse model of anthrax infection. Further studies are needed to optimize protection, evaluate activity in combination with other treatment options, demonstrate activity in a validated primate model of infection, and determine if protection is effective against other potential BW agents.

Topics: Adjuvants, Immunologic; Animals; Anthrax; Anti-Bacterial Agents; Anti-Infective Agents; Ascomycota; Bacillus anthracis; beta-Glucans; Biological Warfare; Bioterrorism; Disease Models, Animal; Female; Glucans; Lung; Mice; Mice, Inbred BALB C; Survival Rate

Sparassis crispa Fr. is an edible mushroom recently cultivable in Japan. It contains a remarkably high content of 6-branched 1,3-beta-D-glucan showing antitumor activity. Using ion-exchange chromatography, a purified beta-glucan preparation, SCG, was prepared. In this study, we examined the hematopoietic response by SCG in cyclophosphamide (CY)-induced leukopenic mice. SCG enhanced the hematopoietic response in CY induced leukopenic mice by intraperitoneal routes over a wide range of concentrations. SCG enhanced the hematopoietic response in CY-treated mice by prior or post administration. Analyzing the leukocyte population by flow cytometry, monocytes and granulocytes in the peritoneal cavity, liver, spleen and bone marrow (BM) recovered faster than in the control group. The ratio of natural killer cells and gammadelta T cells in the liver, spleen and peritoneal cavity was also increased. In contrast, CD4+ CD8+ cells in the thymus were temporarily significantly decreased by the administration of SCG. Interleukin-6 (IL-6) production of CY+SCG-treated peritoneal exdated cells (PECs), spleen cells and bone marrow cells (BMCs) were higher than that of the CY-treated group. By in vitro culture of CY-treated PEC and spleen cells, IL-6 production was enhanced by the addition of SCG. These facts suggested the possibility that IL-6 might be a key cytokine for the enhanced hematopoietic response by SCG.

Topics: Animals; beta-Glucans; Cell Count; Cyclophosphamide; Disease Models, Animal; Dose-Response Relationship, Drug; Glucans; Injections, Intraperitoneal; Interleukin-6; Leukocytes; Leukopenia; Male; Mice; Mice, Inbred ICR; Organ Specificity; Polyporales

Paracoccidioidomycosis (PCM) is a deep mycosis caused by the thermo-dependent dimorphic fungus Paracoccidioides brasiliensis and is prevalent in Latin American countries. Diagnosis of PCM is sometimes difficult outside the endemic countries, thus a rapid and conclusive method for diagnosis of PCM has been anticipated. We compared the sensitivities of a nested PCR method for detecting the gp43 gene and a commercial kit for detecting (1-3)-beta-D-glucan in the blood of experimentally infected mice. Blood samples were collected from mice at 0 (soon after inoculation), 6, 12, 24, 48, and 72 hours and 5, 7, 10, 14, 17, 21, 24, 28 and 56 days after the intravenous inoculation of 10(6) yeast cells of P. brasiliensis, and were separated into clots and plasma. The (1-3)-beta-D-glucan detection kit in the plasma showed positive reactions in some samples within 7 days and 28 and 56 days after infections. In contrast, the PCR method was more sensitive than the (1-3)-beta-D-glucan detection kit throughout the observation period. The clot samples yielded more sensitive PCR-results than did the plasma samples. Although 24 hours is required for the PCR detection, it was confirmed to provide an accurate diagnosis of PCM.

Topics: Adult; Aged; Animals; Antigens, Fungal; beta-Glucans; Biomarkers; Child; Diphosphates; Disease Models, Animal; Drug Combinations; Female; Fungal Proteins; Genes, Fungal; Glucans; Glycoproteins; Humans; Male; Mice; Mice, Inbred Strains; Middle Aged; Nitrates; Paracoccidioides; Paracoccidioidomycosis; Polyethylenes; Polymerase Chain Reaction; Sodium Fluoride

Sparassis crispa is an edible mushroom recently cultivable in Japan. Polysaccharide fractions were prepared from the cultured S. crispa by repeated extraction with hot water (SCHWE), cold NaOH (SCCA), and then hot NaOH (SCHA). HWE was further separated by 1 volume (SCHWE1v) or 4 volumes (SCHWE4v) of ethanol-precipitable fractions. By chemical, enzymic, and NMR analyses, the primary structures of SCHWE1v, SCCA, and SCHA were 6-branched 1,3-beta-glucan, having one branch in approximately every third mainchain unit. All of these fractions showed antitumor activity to the solid form of Sarcoma 180 in ICR mice with strong vascular dilation and hemorrhage reaction. These fractions also showed enhanced hematopoietic response to cyclophosphamide induced leukopenic mice following intraperitoneal or peroral administration.

Topics: Animals; Antineoplastic Agents; beta-Glucans; Disease Models, Animal; Drug Screening Assays, Antitumor; Glucans; Leukocyte Count; Leukopenia; Magnetic Resonance Spectroscopy; Male; Mice; Mice, Inbred ICR; Polyporales; Polysaccharides; Sarcoma 180; Structure-Activity Relationship

Beta-1,3-glucan is a potent stimulator of macrophage functions and has a protective effect against a range of infections in rodent models. We examined whether the agent could also protect against the intracellular Mycobacterium bovis, bacillus Calmette-Guérin (BCG) infection in mice. BCG-susceptible BALB/c mice were injected intravenously (i.v.) with beta-glucan or vehicle 3 days before, or with beta-glucan 7 days after i.v. challenge with live BCG bacilli. The animals were killed 4 or 8 weeks later, their organs were homogenized and applied to object slides and stained with auramin for counting of bacilli, or seeded onto agar in Petri dishes. Mice treated with beta-glucan both pre- and postchallenge had significantly lower numbers of BCG bacilli and BCG colony-forming units in spleen homogenates compared with controls 4 weeks after challenge. A similar, but not statistically significant, tendency was observed in spleen homogenates from mice killed 8 weeks after challenge. In homogenates of liver and lungs there were similar findings, but less pronounced. There was a dose-dependent effect of beta-glucan injected before BCG challenge on the number of BCG bacilli found in spleen and liver homogenates. In addition, antibody cross-reactivity was demonstrated between M. tuberculosis cell wall and beta-glucan. The results suggest that beta-glucan has a protective effect against M. bovis, BCG infection in susceptible mice.

Topics: Animals; Antigens, Bacterial; Antitubercular Agents; beta-Glucans; Cell Wall; Colony Count, Microbial; Cross Reactions; Disease Models, Animal; Female; Glucans; Injections, Intravenous; Liver; Lung; Mice; Mice, Inbred BALB C; Mycobacterium bovis; Spleen; Tuberculosis

The G test containing factor G, fractioned from the Limulus lysate, was used to detect (1-3)-beta-D-glucan in a rat model of aspergillosis. Aspergillus fumigatus strain MF-13, 1 x 10(4) conidia, were inoculated transtracheally into rats treated with cortisone acetate (100 mg/kg) and fed a low-protein (8%) diet. Increased serum (1-3)-beta-D-glucan was found on the sixth day after inoculation in concentrations of 370 +/- 178 pg/ml (mean +/- SD) in untreated controls, and 154 +/- 43 pg/ml in rats treated with 0.5 mg/kg of amphotericin B. On day 11 (1-3)-beta-D-glucan concentrations were 2,590 +/- 2,940 pg/ml and 448 +/- 442 pg/ml, respectively. The elevation in levels of (1-3)-beta-D-glucan increased in correlation with the elevation of galactomannan antigen titers; (1-3)-beta-D-glucan is thus measurable during experimental aspergillosis in rats.

Topics: Amphotericin B; Animals; Aspergillosis; Aspergillus fumigatus; beta-Glucans; Disease Models, Animal; Galactose; Glucans; Horseshoe Crabs; Lung; Male; Mannans; Rats; Rats, Sprague-Dawley

An indirect method to measure beta-glucan, a major structural component of yeast cell walls, is available, but has the disadvantage of requiring the combined use of two assays. Recent reports describe the fungal index, which measures the difference between the conventional limulus test, in which factors C and G react with endotoxin and beta-glucan, and a new endotoxin-specific test, in which only factor C reacts with endotoxin. The G test was developed as a direct method to measure beta-glucan, and contains only factor G reacting with beta-glucan alone. In this study, the G test was examined in sera of rabbits with experimental systemic candidiasis, and compared with the fungal index and mannan assay. The G test showed positive in all rabbits with systemic candidiasis faster and with higher titers than with the fungal index. Three rabbits with fulminant systemic candidiasis showed higher levels of reactivity with the G test and the fungal index than two rabbits with mild reactions. Mannan was positive by at least one serum in four of five rabbits by the latex agglutination test, and there was a good correlation between these assays. The G test is a good serodiagnostic method for the detection of candidiasis.

Topics: Animals; Antigens, Fungal; beta-Glucans; Candidiasis; Disease Models, Animal; Evaluation Studies as Topic; Glucans; Limulus Test; Mannans; Mycology; Rabbits; Sensitivity and Specificity

A series of lipopeptide compounds co-produced during the fermentation of pneumocandin A0 (L-671,329) and related semisynthetic compounds were evaluated in vivo against Pneumocystis carinii pneumonia and systemic candidiasis. In addition, they were tested in vitro against a panel of pathogenic Candida species and in a Candida membrane 1,3-beta-D-glucan synthesis assay. The results of these studies demonstrate that pneumocandin A0 and pneumocandin B0 (L-688,786) are the most potent compounds when considering both antipneumocystis and anticandida activity. Other compounds in the series are selectively more potent against P. carinii or Candida albicans suggesting a diverging structure-activity relationship. Evaluation of these compounds for their ability to inhibit C. albicans 1,3-beta-D-glucan synthesis in vitro demonstrates that they inhibit this process. A positive correlation between 1,3-beta-D-glucan synthesis inhibition and in vitro antifungal activity was also demonstrated for some of the pneumocandins.

Topics: Animals; Anti-Bacterial Agents; Antifungal Agents; beta-Glucans; Candida albicans; Cell Membrane; Disease Models, Animal; Echinocandins; Erythrocytes; Glucans; Hemolysis; Humans; Mice; Microbial Sensitivity Tests; Mitosporic Fungi; Peptides; Peptides, Cyclic; Pneumocystis; Structure-Activity Relationship

A new beta-1,3-D-glucan synthesis inhibitor, L-687,781 is produced by the cultivation of Dictyochaeta simplex ATCC 20960. L-687,781 exhibits potent in vitro antifungal activity as well as anti-Pneumocystis activity in a rat model.

Topics: Animals; Antifungal Agents; beta-Glucans; Candida; Candidiasis; Cryptococcus neoformans; Disease Models, Animal; Fermentation; Fungi; Glucans; Male; Mice; Mitosporic Fungi; Pneumonia, Pneumocystis; Pyrans; Rats; Rats, Inbred Strains