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317
result(s) for
"Glucans - toxicity"
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Asialoglycoprotein receptor targeted delivery of doxorubicin nanoparticles for hepatocellular carcinoma
2017
We report asialoglycoprotein receptor (ASGPR)-targeted doxorubicin hydrochloride (Dox) nanoparticles (NPs) for hepatocellular carcinoma (HCC). Polyethylene sebacate (PES)-Gantrez® AN 119 Dox NPs of average size 220 nm with PDI < 0.62 and ∼20% Dox loading were prepared by modified nanoprecipitation. ASGPR ligands, pullulan (Pul), arabinogalactan (AGn), and the combination (Pul-AGn), were anchored by adsorption. Ligand anchoring enabled high liver uptake with a remarkable hepatocyte:nonparenchymal cell ratio of 85:15. Furthermore, Pul-AGn NPs exhibited an additive effect implying incredibly high hepatocyte accumulation. Galactose-mediated competitive inhibition confirmed ASGPR-mediated uptake of ligand-anchored NPs in HepG2 cell lines. Subacute toxicity in rats confirmed the safety of the NP groups. However, histopathological evaluation suggested mild renal toxicity of AGn. Pul NPs revealed sustained reduction in tumor volume in PLC/PRF/5 liver tumor-bearing Nod/Scid mice up to 46 days. Extensive tumor necrosis, reduced collagen content, reduction in the HCC biomarker serum α-fetoprotein (p < 0.05), a mitotic index of 1.135 (day 46), and tumor treated/tumor control (T/C) values of <0.42 signified superior efficacy of Pul NPs. Furthermore, weight gain in the NP groups, and no histopathological alterations indicated that they were well tolerated by the mice. The high efficacy coupled with greater safety portrayed Pul Dox NPs as a promising nanocarrier for improved therapy of HCC.
Journal Article
β-Glucan exacerbates allergic airway responses to house dust mite allergen
by
Williams, David L.
,
Hadebe, Sabelo
,
Murray, Graeme I.
in
Animals
,
Antigens, Dermatophagoides - immunology
,
Antigens, Dermatophagoides - toxicity
2016
β-(1,3)-Glucan is present in mould cell walls and frequently detected in house dust mite (HDM) faeces. β-Glucan exposure is thought to be associated with pulmonary allergic inflammation in mouse and man, although the published data are inconsistent. Here, we show that highly purified β-glucan exacerbates HDM-induced eosinophilic, T helper 2 type airway responses by acting as an adjuvant, promoting activation, proliferation and polarisation of HDM-specific T cells (1-Derβ T cells). We therefore provide definitive evidence that β-glucan can influence allergic pulmonary inflammation.
Journal Article
Tocopheryl Phosphate Inhibits Rheumatoid Arthritis-Related Gene Expression In Vitro and Ameliorates Arthritic Symptoms in Mice
by
Takatsu, Hirokatsu
,
Kogure, Kentaro
,
Hama, Susumu
in
alpha-Tocopherol
,
alpha-Tocopherol - analogs & derivatives
,
alpha-Tocopherol - pharmacology
2022
Anti-rheumatoid arthritis (RA) effects of α-tocopherol (α-T) have been shown in human patients in a double-blind trial. However, the effects of α-T and its derivatives on fibroblast-like synoviocytes (FLS) during the pathogenesis of RA remain unclear. In the present study, we compared the expression levels of genes related to RA progression in FLS treated with α-T, succinic ester of α-T (TS), and phosphate ester of α-T (TP), as determined via RT-PCR. The mRNA levels of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), matrix metalloproteinase (MMP)-3, and MMP-13 were reduced by treatment with TP without cytotoxicity, while α-T and TS did not show such effects. Furthermore, intraperitoneal injection of TP ameliorated the edema of the foot and joint and improved the arthritis score in laminarin-induced RA model mice. Therefore, TP exerted anti-RA effects through by inhibiting RA-related gene expression.
Journal Article
Dectin-1 and inflammation-associated gene transcription and expression in mouse lungs by a toxic (1,3)-β-d glucan
by
Sun, M
,
Downey, J
,
Gilyan, A
in
Animals
,
beta-Glucans - administration & dosage
,
beta-Glucans - toxicity
2010
The form of (1-3)-β-d glucan found in the cell walls of the anamorphic Trichocomaceae that grow on damp building materials is considered to have potent toxic and inflammatory effects on cells of the respiratory system. It is also considered to have a potential role in the development of non-allergenic respiratory health effects. While human studies involving experimental exposures all point to the inflammatory potential of pure curdlan, a linear (1-3)-β-d glucan in a triple helix configuration, animal experiments result in conflicting conclusions concerning the inflammatory potency of this glucan. However, because mice appear to be a better model than guinea pigs for exploring the respiratory effects of curdlan and because molecular mechanisms associated with this glucan remain largely unknown, we conducted further work to clarify the role of curdlan on the inflammatory response using our mouse model of lung disease. This study used in situ hybridization (ISH) to probe dectin-1 mRNA transcription with a digoxigenin-labeled cDNA probe, with reverse transcription (RT)-PCR based arrays used to measure inflammation gene and receptor transcriptional responses. Also, immunohistochemistry (IHC) was used to probe dectin-1 as well as anti-mouse Ccl3, Il1-alpha, and TNF-alpha expression to evaluate dose and time-course (4 and 12 h) postexposure (PE) response patterns in the lungs of intratracheally instilled mice exposed to a single 50 μl dose of curdlan at 10⁻⁷, 10⁻⁸, 10⁻⁹, and 10⁻¹⁰ M/animal (=4 μg to 4 ng curdlan/kg lung wt). Dectin-1 mRNA transcription and expression was observed in bronchiolar epithelium, alveolar macrophages (AMs), and alveolar type II cells (ATIIs) of lungs exposed to 4 μg to 40 ng curdlan/kg lung wt, at both time points. Compared to controls, array analysis revealed that 54 of 83 genes assayed were significantly modulated by curdlan. mRNA transcription patterns showed both dose and time dependency, with highest transcription levels in 10⁻⁷ and 10⁻⁸ M treatment animals, especially at 4-h PE. Nine gene mRNA transcripts (Ccl3, Ccl11, Ccl17, Ifng, Il1α, Il-20, TNF-α, Tnfrsf1b, and CD40lg) were significantly expressed at all doses suggesting they may have a central role in immunomodulating curdlan exposures. IHC revealed Ccl3, Il1-alpha, and TNF-alpha expression in bronchiolar epithelium, AMs and ATIIs illustrate the important immunomodulatory role that these cells have in the recognition of, and response to glucan. Collectively, these results confirm the inflammatory nature of curdlan and demonstrate the complex of inflammation-associated gene responses induced by (1-3)-β-d glucan in triple helical forms. These observations also provide a biological basis for the irritant and inflammatory response to curdlan observed in humans and animals in experimental studies.
Journal Article
Toxicological Assessment of β-(1à6)-Glucan (Lasiodiplodan) in Mice during a 28-Day Feeding Study by Gavage
by
Carraro, Emerson
,
Dekker, Robert
,
Alves da Cunha, Mário
in
Animals
,
beta-Glucans - administration & dosage
,
beta-Glucans - toxicity
2012
Studies evaluating the toxicity caused by fungal exopolysaccharides of the β-(1→6)-D-glucan type are rare. In this study, the toxicological effects of sub-chronic treatments with lasiodiplodan (β-(1→6)-D-glucan from Lasiodiplodia theobromae MMPI) were evaluated in mice through the assessment of biochemical, hematological, and histopathological alterations. Thirty-two mice (16 male, 16 female) were used in this study divided in two groups; one group received lasiodiplodan (50 mg/kg body weight) daily for 28 days via gavage, and another (control group) received saline during the same period. Blood samples were collected via cardiac puncture for hematological and biochemical analyses. Liver, heart, kidney, and spleen were collected for histopathological analysis. Statistical analysis was performed through one-way analysis of variance and only p < 0.05 F-values were presented. Significant reduction in blood glucose in the male group (35%; p < 0.01), transaminases activity in both sexes (AST and ALT; ~35%; p < 0.05), and urea (20%; p < 0.01) in the female group was observed with the lasiodiplodan treatment. The results showed that sub-chronic treatments with lasiodiplodan did not generate hematological and histopathological alterations leading to signs of toxicity in healthy mice, independent of gender.
Journal Article
Early life microbial exposure and fractional exhaled nitric oxide in school-age children: a prospective birth cohort study
by
Casas, Lidia
,
Smit, Henriëtte A
,
Sunyer, Jordi
in
Air Pollution, Indoor - analysis
,
Asthma in children
,
Bacteria - chemistry
2013
Background
Inflammation is a key factor in the pathogenesis of respiratory diseases. Early life exposure to microbial agents may have an effect on the development of the immune system and on respiratory health later in life.
In the present work we aimed to evaluate the associations between early life microbial exposures, and fractional exhaled nitric oxide (FeNO) at school age.
Methods
Endotoxin, extracellular polysaccharides (EPS) and β(1,3)-D-glucan were measured in living room dust collected at 2–3 months of age in homes of participants of three prospective European birth cohorts (LISA, n = 182; PIAMA, n = 244; and INMA, n = 355). Home dampness and pet ownership were periodically reported by the parents through questionnaires. FeNO was measured at age 8 for PIAMA and at age 10/11 for LISA and INMA. Cohort-specific associations between the indoor microbial exposures and FeNO were evaluated using multivariable regression analyses. Estimates were combined using random-effects meta-analyses.
Results
FeNO at school age was lower in children exposed to endotoxin at age 2–3 months (β -0.05, 95% confidence interval (CI) -0.10;-0.01) and in children with reported dog ownership during the first two years of life (GM ratio 0.82, CI 0.70-0.96). FeNO was not significantly associated with early life exposure to EPS, β(1,3)-D-glucan, indoor dampness and cat ownership.
Conclusion
Early life exposure to bacterial endotoxin and early life dog ownership are associated with lower FeNO at school age. Further studies are needed to confirm our results and to unravel the underlying mechanisms and possible clinical relevance of this finding.
Journal Article
Acceleration of SLE-like syndrome development in NZBxNZW F1 mice by beta-glucan
by
Magro, G
,
Coco, M
,
Quattrocchi, C
in
Animals
,
beta-Glucans - administration & dosage
,
beta-Glucans - toxicity
2014
Beta-glucans are naturally occurring polysaccharides that exert important immunostimulatory activities. In the present study, we evaluated whether beta-glucans could modulate the development and the course of systemic lupus erythematosus (SLE). To this aim, we employed the classical model of SLE represented by the F1 hybrid between the NZB and NZW mouse strains which develop severe lupus-like phenotypes comparable to that of SLE patients. The administration of beta-glucan was associated to a more aggressive development of the disease and a worse prognosis, as observed from the clinical, biochemical and histopathological data. This finding implies that restraint should be practised in the possible use of beta-glucans as immunomodulators in human therapy in the context of SLE.
Journal Article
S-maltoheptaose targets syndecan-bound effectors to reduce smoking-related neutrophilic inflammation
2015
Cigarette smoke induces injury and neutrophilic inflammation in the airways of smokers. The stability and activity of inflammatory effectors, IL8 and neutrophil elastase (NE), can be prolonged by binding to airway heparan sulfate (HS)/syndecan-1, posing risk for developing chronic obstructive pulmonary disease(COPD). We hypothesize that antagonizing HS/syndecan-1 binding of the inflammatory effectors could reduce smoking-related neutrophil-mediated airway inflammation. Analysis of bronchoalveolar lavage fluid(BALF) of COPD patients found both total and unopposed NE levels to be significantly higher among smokers with COPD than non-COPD subjects. Similar NE burden was observed in smoke-exposed rats compared to sham air controls. We chose sulfated-maltoheptaose(SM), a heparin-mimetic, to antagonize HS/sydecan-1 binding of the inflammatory mediators in airway fluids and lung tissues of the smoke-exposed rat model. Airway treatment with SM resulted in displacement of CINC-1 and NE from complexation with bronchio-epithelial HS/syndecan-1, dissipating the chemokine gradient for neutrophil flux across to the bronchial lumen. Following SM displacement of NE from shed HS/syndecan-1 in bronchial fluids, NE became accessible to inhibition by α
1
-antitrypsin endogenous in test samples. The antagonistic actions of SM against syndecan-1 binding of NE and CINC-1 in smoke-exposed airways suggest new therapeutic opportunities for modulating airway inflammation in smokers with SM delivery.
Journal Article
Induction of Dectin-1 and asthma-associated signal transduction pathways in RAW 264.7 cells by a triple-helical (1, 3)-β-d glucan, curdlan
2013
People living in damp buildings are typically exposed to spore and mycelial fragments of the fungi that grow on damp building materials. There is experimental evidence that this exposure to triple-helical (1, 3)-β-
d
glucan and low molecular weight toxins may be associated with non-atopic asthma observed in damp and moldy buildings. However, the mechanisms underlying this response are only partially resolved. Using the pure (1, 3)-β-
d
glucan, curdlan, and the murine macrophage cell line, RAW 264.7, there were two objectives of this study. The first was to determine whether signal transduction pathways activating asthma-associated cell signaling pathways were stimulated using mouse transduction Pathway Finder
®
arrays and quantitative real-time (QRT) PCR. The second objective was to evaluate the dose and temporal responses associated with transcriptional changes in asthma-associated cytokines, the signal transduction receptor gene
Dectin
-
1,
and various transcription factor genes related to the induction of asthma using customized RT-PCR-based arrays. Compared to controls, the 10
−7
M curdlan treatment induced significant changes in gene transcription predominately in the
NFkB, TGF
-
β, p53, JAK/STAT, P13/AKT
, phospholipase C, and stress signaling pathways. The 10
−8
M curdlan treatment mainly induced
NFkB
and
TGF
-
β
pathways. Compared to controls, curdlan exposures also induced significant dose- and time-dependent changes in the gene translations. We found that that curdlan as a non-allergenic potentiator modulates a network of transduction signaling pathways not only associated with TH-1, TH-2, and TH-3 cell responses including asthma potentiation, but a variety of other cell responses in RAW 264.7 cells. These results help provide mechanistic basis for some of the phenotypic changes associated with asthma that have been observed in in vitro, in vivo, and human studies and open up a hypothesis-building process that could explain the rise of non-atopic asthma associated with fungi.
Journal Article
Enhancement of the Solubility and Efficacy of Poorly Water-Soluble Drugs by Hydrophobically-Modified Polysaccharide Derivatives
by
Appel, Martine
,
Picton, Luc
,
Le Cerf, Didier
in
Animals
,
Antineoplastic Agents, Phytogenic - chemistry
,
Antineoplastic Agents, Phytogenic - pharmacology
2007
This work was intended to develop and evaluate a new polymeric system based on amphiphilic carboxymethylpullulans (CMP(49)C(8) and CMP(12)C(8)) that can spontaneously self-assemble in aqueous solutions and efficiently solubilize hydrophobic drugs.
The self-assembling properties of CMP(49)C(8) and CMP(12)C(8) were characterized by fluorescence spectroscopy and surface tension measurements. The solubilization of benzophenone and docetaxel was assessed from surface tension measurements, UV spectrometry and HPLC assays. The in vitro cytoxicity of CMP(49)C(8) solutions and the docetaxel commercial vehicle (Tween 80/Ethanol-water) were evaluated in the absence and in the presence of docetaxel.
Compared to CMP(12)C(8), CMP(49)C(8) in aqueous solutions appeared to self-organize into monomolecular aggregates containing hydrophobic nanodomains, and to significantly increase the apparent solubility of benzophenone. Docetaxel solubility could also be improved in the presence of CMP(49)C(8) but to a lower extent due to the surface properties of the drug. Nevertheless, in vitro, the cytotoxicity studies revealed that against cancer cells, the CMP(49)C(8)-docetaxel formulation was equipotent to the commercial docetaxel one. Furthermore, in the absence of the drug, CMP(49)C(8) appeared less cytotoxic against macrophages than the Tween 80/Ethanol-water.
CMP(49)C(8) is a good candidate for solubilizing hydrophobic drugs and could be applied to docetaxel formulations.
Journal Article