β-Glucan from Saccharomyces cerevisiae alleviates oxidative stress in LPS-stimulated RAW264.7 cells via Dectin-1/Nrf2/HO-1 signaling pathway

β-Glucan from Saccharomyces cerevisiae has been described to be effective antioxidants, but the specific antioxidation mechanism of β-glucan is unclear. The objectives of this research were to determine whether the β-glucan from Saccharomyces cerevisiae could regulate oxidative stress through the Dectin-1/Nrf2/HO-1 signaling pathway in lipopolysaccharides (LPS)-stimulated RAW264.7 cells. In this study, we examined the effects of β-glucan on the enzyme activity or production of oxidative stress indicators in LPS-stimulated RAW264.7 cells by biochemical analysis and the protein expression of key factors of Dectin-1/Nrf2/HO-1 signaling pathway by immunofluorescence and western blot. The biochemical analysis results showed that β-glucan increased the LPS-induced downregulation of enzyme activity of intracellular heme oxygenase (HO), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) while decreasing the production of reactive oxygen species (ROS) and malondialdehyde (MDA). Furthermore, immunofluorescence results showed that β-glucan can activate the nuclear factor erythroid 2-related factor 2 (Nrf2). The antioxidant mechanism study indicated that β-glucan activated dendritic-cell-associated C-type lectin 1 (Dectin-1) receptors mediated Nrf2/HO-1 signaling pathway, thereby downregulating the production of ROS and thus produced the antioxidant effects in LPS-stimulated RAW 264.7 cells. In conclusion, these results indicate that β-glucan potently alleviated oxidative stress via Dectin-1/Nrf2/HO-1 in LPS-stimulated RAW 264.7 cells.

Survival Impact of Anti-GD2 Antibody Response in a Phase II Ganglioside Vaccine Trial Among Patients With High-Risk Neuroblastoma With Prior Disease Progression

PURPOSE

Anti-GD2 monoclonal antibody (mAb) has proven efficacy in high-risk neuroblastoma (HR-NB). A small phase I GD2/GD3 vaccine trial (n = 15) described long-term survival and a favorable safety profile among patients with a history of disease progression (PD). The kinetics of mounting antibody response to vaccine and its prognostic impact on survival are now investigated in a phase II study (ClinicalTrials.gov identifier: NCT00911560).

PATIENTS AND METHODS

One hundred two patients with HR-NB who achieved remission after salvage therapies were enrolled in this trial. They received seven subcutaneous injections of GD2/GD3 vaccine spanning 1 year plus oral β-glucan starting at week 6 after the third dose of vaccine. Serum anti-vaccine antibody titers were quantified by enzyme-linked immunosorbent assay. Single nucleotide polymorphisms (SNPs) were determined by quantitative polymerase chain reaction. Kaplan-Meier and landmark Cox Regression models were used for survival estimates.

RESULTS

Patients had a history of one (63%), two (21%), or three to six (16%) episodes of PD. 82% of them progressed following anti-GD2 mAb (m3F8/dinutuximab/naxitamab) therapy. Vaccine-related toxicities were self-limited injection-associated local reactions and fever without any > grade 3 toxicities. The progression-free survival (PFS) was 32% ± 6%, and the overall survival (OS) was 71% ± 7% at 5 years. Serum anti-GD2 (immunoglobulin G1 [IgG1] and IgM) and anti-GD3 (IgG1) titers showed notable increases following the initiation of β-glucan at week 6. There was an association between IgG1 titer and SNP rs3901533 of dectin-1, the β-glucan receptor. Multivariable analyses showed that anti-GD2-IgG1 titer ≥ 150 ng/mL by week 8 was associated with favorable PFS and OS, while having prior episodes of PD and the time from last PD to vaccine were associated with PFS.

CONCLUSION

GD2/GD3 vaccine plus β-glucan elicited robust antibody responses in patients with HR-NB with prior PD. Higher anti-GD2-IgG1 titer was associated with improved survival.

Food 4 Health - He Oranga Kai: Assessing the efficacy, acceptability and economic implications of Lactobacillus rhamnosus HN001 and β-glucan to improve glycated haemoglobin, metabolic health, and general well-being in adults with pre-diabetes: study protocol for a 2 × 2 factorial design, parallel group, placebo-controlled randomized controlled trial, with embedded qualitative study and economic analysis

BACKGROUND

The rates of pre-diabetes and type 2 diabetes mellitus are increasing worldwide, producing significant burdens for individuals, families, and healthcare systems. In New Zealand, type 2 diabetes mellitus and pre-diabetes disproportionally affect Māori, Pacific, and South Asian peoples. This research evaluates the efficacy, acceptability, and economic impact of a probiotic capsule and a prebiotic cereal intervention in adults with pre-diabetes on metabolic and mental health and well-being outcomes.

METHODS

Eligible adults (n = 152) aged 18-80 years with pre-diabetes (glycated haemoglobin 41-49 mmol/mol) will be enrolled in a 2 × 2 factorial design, randomised, parallel-group, placebo-controlled trial. Computer-generated block randomization will be performed independently. Interventions are capsulated Lactobacillus rhamnosus HN001 (6 × 109 colony-forming units/day) (A) and cereal containing 4 g β-glucan (B), placebo capsules (O1), and calorie-matched control cereal (O2). Eligible participants will receive 6 months intervention in the following groups: AB, AO1, BO2, and O1O2. The primary outcome is glycated haemoglobin after 6 months. Follow-up at 9 months will assess the durability of response. Secondary outcomes are glycated haemoglobin after 3 and 9 months, fasting glucose, insulin resistance, blood pressure, body weight, body mass index, and blood lipid levels. General well-being and quality of life will be measured by the Short-Form Health Survey 36 and Depression Anxiety Stress Scale 21 at 6 and 9 months. Outcome assessors will be blind to capsule allocation. An accompanying qualitative study will include 24 face-to-face semistructured interviews with an ethnically balanced sample from the β-glucan arms at 2 months, participant focus groups at 6 months, and three health professional focus groups. These will explore how interventions are adopted, their acceptability, and elicit factors that may support the uptake of interventions. A simulation model of the pre-diabetic New Zealand population will be used to estimate the likely impact in quality-adjusted life years and health system costs of the interventions if rolled out in New Zealand.

DISCUSSION

This study will examine the efficacy of interventions in a population with pre-diabetes. Qualitative components provide rich description of views on the interventions. When combined with the economic analysis, the study will provide insights into how to translate the interventions into practice.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, ACTRN12617000990325. Prospectively registered on 10 July 2017.

The association between endotoxin and beta-(1 → 3)-D-glucan in house dust with asthma severity among schoolchildren

BACKGROUND

Asthma severity can be affected by microbial exposures. However, less is known about the specific indoor agents aggravating the disease in children. We examined the associations between indoor endotoxin and beta-(1 → 3)-D-glucan exposures and asthma severity in children with asthma.

METHODS

A clinical cross-sectional study of schoolchildren (aged 7-17 years) was conducted in the province of Saskatchewan, Canada. Children with asthma (n = 116) were identified from 335 participants using a combination of survey responses and objective clinical assessments. We then ascertained asthma severity based on recommended guidelines (continuous daytime asthma symptoms, frequent nighttime asthma symptoms, and ≤ 60% predicted FEV₁). Levels of indoor endotoxin and beta-(1 → 3)-D-glucan were measured in dust samples obtained from play area floors and child's mattresses.

RESULTS

The study population of 116 children with asthma was comprised of 75.9% mild asthma and 24.1% moderate/severe asthma. Higher mattress endotoxin concentration was associated with increased odds of moderate/severe asthma [adjusted odds ratio (aOR) = 11.40, 95% confidence interval (CI): 1.45-89.43] while higher beta-(1 → 3)-D-glucan concentration (aOR = 0.16, 95% CI: 0.03-0.89) and load (aOR = 0.10, 95% CI: 0.02-0.72) in play areas were inversely associated with moderate/severe asthma. Furthermore, higher mattress endotoxin concentration was associated with lower FVC (p = 0.01) and FEV₁ (p = 0.03). These associations were not seen for beta-(1 → 3)-D-glucan.

CONCLUSION

Our results showed differential effects of microbial exposures on childhood asthma severity and further highlight domestic endotoxin exposure effects on respiratory health outcomes in children with asthma.

Efficacy of carboxymethyl beta-glucan in cervical intraepithelial neoplasia: a retrospective, case-control study

BACKGROUND

Persistent human papillomavirus (HPV) infection constitutes the principal risk factor for the development of cervical intraepithelial neoplasia (CIN) and cervical cancer. For this reason, new drugs have been studied to support the host immune system against the HPV infection. The aim of this retrospective, case-control study was to detect the efficacy and safety of carboxymethyl β-glucan (Colpofix®) gel as adjuvant therapy in HPV infection.

METHODS

The medical records of patients attending the Colposcopy Service of four hospitals in Rome from 2011 to 2013 were collected. Case arm consisted of patients submitted to local therapy with Colpofix®. Control arm comprised patients who did not receive this therapy. A total of 999 patients were included, divided into four groups, according to their cytological and histological specimens, colposcopy and subsequent management.

RESULTS

Local therapy with Colpofix® gel resulted effective with respect to no therapy for the regression of low-grade CIN (CIN1) in patients submitted to follow up (P=0.0204), while it was no effective for the regression of CIN1 submitted to ablative therapy and high-grade CIN (CIN 2+) (P value not significant).

CONCLUSIONS

In conclusion, Colpofix® gel represents a valid alternative to "wait and see" strategy in patients affected by CIN1. Further prospective studies are warranted to confirm these results.

Efficacy and safety of a medical device in reducing nasal obstruction in allergic children

AIM

Despite the availability of a number of pharmacological options, relief of allergic rhinitis (AR) symptoms, especially nasal obstruction, is often limited and local and systemic adverse reactions are not infrequent. The main aim of the present pilot study was to provide subjective and objective evidence of the clinical efficacy in reducing symptoms and safety of a medical device-Grip stop DMG (lactoferrin, carboximetil β-glucan, D-panthenol, dipotassiumglycyrrhizinate) in children affected by allergic rhinitis.

METHODS

A prospective study with a pre- and post-design has been performed consecutively enrolling 50 pediatric both genders patients affected by persistent AR. Patients received 2 puffs into each nostril twice a day over the course of 4 weeks. The severity of AR symptoms was assessed subjectively as measured by a 0 to 5 Visual Analog Scale, and objectively through active anterior rhinomanometry (AAR) and by means of the evaluation of mucociliary transport time (MCTt). Differences in symptoms scores measured before and after the treatment were compared using Paired-Sample Wilcoxon Signed Rank Test. Proportion of participants with adverse effects attributed to the treatment was computed. The relationship between the subjective score and the AAR and MCT measurements was also assessed.

RESULTS

All considered symptoms, including nasal congestion, significantly improved after treatment (P<0.001), while only 1 patient suffered from moderate adverse effects.

CONCLUSION

Results confirm efficacy and safety of this device used in the pediatric population. As previously reported in the scientific literature, also in our study, patient's perception of nasal symptoms corresponded with objective testing.

Exposure to Beta-(1,3)-D-glucan in house dust at age 7-10 is associated with airway hyperresponsiveness and atopic asthma by age 11-14

BACKGROUND

Mould exposure has been linked to childhood asthma and bronchial hyper-responsiveness. Few studies have assessed beta-(1,3)-d-glucan (beta-glucan), a significant fungal cell wall constituent, in relation to asthma in adolescence.

OBJECTIVE

To determine whether house dust-derived beta-glucan exposure at age 7-10 is associated with the development and persistence of atopic and non-atopic asthma, and bronchial hyper-responsiveness (BHR) by age 11-14.

METHODS

Dust samples were collected from the 1995 Study of Asthma, Genes, and Environment (SAGE) birth cohort. This cohort was derived from Manitoba provincial healthcare administrative records of children high and low risk for asthma. Samples were collected from the homes of 422 children at age 7-10 and analyzed using beta-glucan and endotoxin-specific Limulus Amoebocyte Lysate assays. Asthma, atopy, and BHR status of each child were also assessed at ages 7-10 and 11-14.

RESULTS

At age 7-10, beta-glucan dust levels in the home were associated with persistent atopic asthma at age 11-14 (OR 1.79 for each unit increase in levels, 95% CI 1.14-2.81), independent of endotoxin exposure, and Alternaria or Cladosporium sensitization. The likelihood of BHR almost doubled with unit increases in dust beta-glucan in asthmatic children. In children without asthma, exposure to high beta-glucan levels at age 7-10 also elevated risk for BHR in adolescence (OR 1.74, 95% CI 1.05-2.89). New-onset atopic asthma was twice more likely following high beta-glucan exposure in children without asthma but the association did not reach statistical significance. No associations were evident with concurrent asthma phenotype at age 7-10 or non-atopic asthma at age 11-14.

CONCLUSION

These findings implicate home beta-glucan exposure at school-age as a risk factor for persistent atopic asthma and new-onset BHR. The higher prevalence of BHR in urban adolescents may be propagated by this home exposure.

Evaluation of β-D-glucan biopolymer as a novel mycotoxin binder for fumonisin and deoxynivalenol in soybean feed

The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing mycotoxins in animal feed. This study aimed to evaluate the β-D-glucan biopolymers as a mycotoxin binder for fumonisin (FUM) and deoxynivalenol (DON) toxins as well as their effect on the nutritional value of soybean, which is considered one of the important feed row materials. The evaluation was carried out using some toxigenic Fusarium isolates (Fusarium solani, F. oxysporum, and F. verticillioides) in vitro and in vivo. The FUM and DON levels were determined by immune affinity column. The F. verticillioides was the most toxigenic, followed by F. oxysporum and lastly F. solani, while secretion of DON toxin was determined to be greater than FUM with all the tested fungi. The effectiveness of β-D-glucan biopolymers on FUM and DON absorption was greater than clay and calcium propionate. In vivo, treating soybean seeds with β-D-glucan biopolymers led to reduction in the level of FUM and DON toxins in seeds artificially inoculated by F. verticillioides. β-D-glucan treatment also has a low effect on nutritional components of the seeds compared to untreated ones. In conclusion, this study found a new approach to reduce Fusarium mycotoxins in feed to an allowable safe limit and at the same time maintaining the nutritional value of these materials.

Clinical outcomes of a 2-y soy isoflavone supplementation in menopausal women

BACKGROUND

Soy isoflavones are naturally occurring phytochemicals with weak estrogenic cellular effects. Despite numerous clinical trials of short-term isoflavone supplementation, there is a paucity of data regarding longer-term outcomes and safety.

OBJECTIVE

Our aim was to evaluate the clinical outcomes of soy hypocotyl isoflavone supplementation in healthy menopausal women as a secondary outcome of a trial on bone health.

DESIGN

A multicenter, randomized, double-blind, placebo-controlled 24-mo trial was conducted to assess the effects of daily supplementation with 80 or 120 mg aglycone equivalent soy hypocotyl isoflavones plus calcium and vitamin D on the health of 403 postmenopausal women. At baseline and after 1 and 2 y, clinical blood chemistry values were measured and a well-woman examination was conducted, which included a mammogram and a Papanicolaou test. A cohort also underwent transvaginal ultrasound measurements to assess endometrial thickness and fibroids.

RESULTS

The baseline characteristics of the groups were similar. After 2 y of daily isoflavone exposure, all clinical chemistry values remained within the normal range. The only variable that changed significantly was blood urea nitrogen, which increased significantly after 2 y (P = 0.048) but not after 1 y (P = 0.343) in the supplementation groups. Isoflavone supplementation did not affect blood lymphocyte or serum free thyroxine concentrations. No significant differences in endometrial thickness or fibroids were observed between the groups. Two serious adverse events were detected (one case of breast cancer and one case of estrogen receptor-negative endometrial cancer), which was less than the expected population rate for these cancers.

CONCLUSION

Daily supplementation for 2 y with 80-120 mg soy hypocotyl isoflavones has minimal risk in healthy menopausal women. This trial was registered at clinicaltrials.gov as NCT00665860.

Nasal hyperresponders and atopic subjects report different symptom intensity to air quality: a climate chamber study

Short-term exposure to dust and dust added with beta-(1,3)-d-glucan or aldehydes may cause sensory reactions. In random order, we exposed 36 volunteers in a climate chamber to clean air, office dust, dust with glucan, and dust with aldehydes. Three groups of subjects were exposed, eleven were non-atopic with nasal histamine hyperreactivity, 13 were non-atopic, and 12 were atopic. Subjective ratings of symptoms and general health were registered four times during four 6-h exposure sessions. Six symptom intensity indices were constructed. The nasal hyperreactive group had a high and time-dependent increase of mucous membrane irritations, whereas the atopic group had a low and stable rate of irritations with exposure time, close to the reference group (P = 0.02 for differences between the groups with respect to time under exposure for Weak Inflammatory Responses and P = 0.05 for Irritative Body Perception, significance mainly because of the nasal hyperreactive group). Exposure to dust, with or without glucan or aldehydes, showed increased discomfort measured by the index for Constant Indoor Climate, and dust with glucan had a similar effect for the index for Lower Respiratory Effects. For Psychological and Neurological Effects these were dependent on group affiliation, thus preventing a uniform statement of exposure effects for all three investigated groups.

PRACTICAL IMPLICATIONS

Opportunities for identifying persons with high or low sensitivity to low-level exposures are important in preventive medicine and will reduce intra-group variability and thus increase the power of experimental and epidemiological studies searching for correlations between exposures and health effects. The contrast between nasal hyperreactive on one side and atopic and reference subjects on the other side is particularly important. The atopic group indicated a non-homogenous reaction depending on their hyperreactive status, a finding that could be important but needs further confirmation.

Effects on human eyes caused by experimental exposures to office dust with and without addition of aldehydes or glucan

Thirty-six volunteers (in three susceptibility groups: 11 subjects were non-allergic with nasal histamine hypersensitivity, 13 were non-allergic with normal sensitivity, and 12 were pollen allergic with or without nasal hypersensitivity) were exposed for three and a half hours in a climate chamber. Each subject was exposed to clean air (dust 45 +/- 38 microg/m(3) total suspended particle, TSP), house dust at 357 +/- 180 microg/m(3) TSP, house dust 382 +/- 175 microg/m(3) TSP with added glucan (50 ng/m(3)) and house dust 394 +/- 168 microg/m(3) TSP with added aldehydes corresponding to a gaseous phase of 300 microg/m(3) in the air. The study was explorative by nature. No significant effects of exposures as such were seen on break-up time, conjunctival epithelial damage score and Trolox Equivalent Antioxidant Capacity (TEAC) in tear film and subjective ratings. However, in TEAC a significant different time course was seen during exposures to aldehyde-containing dust indicating a subacute and late response to the exposures. Perceived eye irritation increased significantly during exposures to normal dust. The perception ratings were highly correlated, whereas no correlation was found between the subjective responses and the objective measurements.

PRACTICAL IMPLICATIONS

The findings indicate that measurement effects on the eyes are rather insensitive measures of short time effects of office dust exposures.

Lethal and severe coronary arteritis in DBA/2 mice induced by fungal pathogen, CAWS, Candida albicans water-soluble fraction

CAWS is a microbial pathogen-associated molecular patterns (PAMPs) produced by Candida albicans. CAWS is a mannoprotein-beta-glucan complex and secreted into the culture supernatant. CAWS has various biological effects, causing acute shock and disrupting vascular permeability. Intraperitoneal administration of CAWS induces coronary arteritis in various strains of inbred mice. The CAWS-induced coronary arteritis is strain-dependent and most severe in DBA/2 mice with a significant number of these animals expiring with cardiomegaly during the observation period. In vivo and in vitro, splenocytes of DBA/2 mice produced various cytokines, such as IL-6, TNF-alpha, and IFN-gamma in response to CAWS. GM-CSF was also produced in response to CAWS. The production of cytokines was significantly enhanced in the presence of recombinant GM-CSF. In contrast, anti-GM-CSF significantly reduced the production of TNF-alpha and IFN-gamma. Augmented production of cytokines in response to CAWS would be a key to the severity of coronary arteritis.

Pediococcus parvulus gtf gene encoding the GTF glycosyltransferase and its application for specific PCR detection of beta-D-glucan-producing bacteria in foods and beverages

Exopolysaccharide production by lactic acid bacteria is beneficial in the dairy and oat-based food industries and is used to improve the texture of the fermented products. However, beta-D-glucan-producing bacteria are considered spoilage microorganisms in alcoholic beverages because their secreted exopolysaccharides alter the viscosity of cider, wine, and beer, rendering them unpalatable. The plasmidic glycosyltransferase (gtf) gene of the Pediococcus parvulus 2.6 strain isolated from ropy cider has been cloned and sequenced, and its GTF product was functionally expressed in Streptococcus pneumoniae. The GTF protein, which has glycosyltransferase activity, belongs to the COG1215 membrane-bound glycosyltransferase family, and agglutination tests revealed that the enzyme enables S. pneumoniae to synthesize beta-D-glucan. PCR amplification and Southern blot hybridization showed that the gtf gene is also present at different genomic locations in the beta-D-glucan producers Lactobacillus diolivorans G77 and Oenococcus oeni I4 strains, also isolated from ropy cider. A PCR assay has been developed for the detection of exopolysaccharide-producing bacteria. Forward and reverse primers, included respectively in the coding sequences of the putative glycosyltransferase domain and the fifth trans-membrane segment of the GTF, were designed. Analysis of 76 ropy and nonropy lactic acid bacteria validated the method for specific detection of beta-D-glucan homopolysaccharide producer Pediococcus, Lactobacillus, and Oenococcus strains. The limit of the assay in cider was 3 X 10(2) CFU/ml. This molecular method can be useful for the detection of ropy bacteria in cider before spoilage occurs, as well as for isolation of new exopolysaccharide-producing strains of industrial interest.

(1-->3)-beta-D-glucan does not induce acute inflammation after nasal deposition

To assess if (1→3)-β-D-glucan, a microbial cell wall agent normally present in pollen, has the ability to produce pollenlike response, sensitive persons received a nasal deposition of two doses of (1→3)-β-D-glucan. The percentage of eosinophils and amount of eotaxin were measured in nasal lavage 30 minutes and 24 hours after challenge. No effect could be demonstrated. The absence of an inflammatory response after (1→3)-β-D-glucan application confirms earlier findings in inhalation studies.

Curdlan sulphate in human severe/cerebral Plasmodium falciparum malaria

Preclinical studies have shown that curdlan sulphate (CRDS), a sulphated 1-->3-beta-D glucan, inhibits Plasmodium falciparum in vitro and down-modulates the immune response. A direct, non-specific effect on cytoadherence and rosetting may be predicted, as has been described with other sulphated polysaccharides, e.g. heparin. The anticoagulant effect of CRDS is 10-fold lower than heparin. Curdlan sulphate has, therefore, emerged as a candidate for adjunct medication in the treatment of severe/cerebral malaria. Two clinical studies were conducted using CRDS as adjunct medication to conventional therapy (artesunate) in patients with severe and severe/cerebral malaria. Both studies were double-blind and placebo-controlled to evaluate the efficacy and safety of the combination. Curdlan sulphate appeared to reduce the severity of the disease process, e.g. fever clearance time was shortened. Due to the small number of patients, there was no difference in mortality. The two treatment arms in both studies showed similar results for all laboratory parameters. The only adverse event recorded during CRDS treatment was an increase in activated partial thromboplastin time. This can be monitored easily. It seems that the patients who may benefit most are severe/cerebral cases with no organ damage on admission.

(1-->3)-Beta-D-glucans and respiratory health: a review of the scientific evidence

(1-->3)-Beta-D-glucan are non-allergenic structural cell wall components of most fungi that have been suggested to play a causal role in the development of respiratory symptoms associated with indoor fungal exposure. This review describes the currently available epidemiological literature on health effects of (1-->3)-beta-D-glucan, focusing on atopy, airway inflammation and symptoms, asthma, and lung function. In addition to population studies, studies in human volunteers experimentally exposed to (1-->3)-beta-D-glucan are described as well as relevant animal studies. Furthermore, the review discusses exposure assessment methods, the potential for exposure control and it concludes with identifying research needs. The observational and experimental studies reviewed suggested some association between (1-->3)-beta-D-glucan exposure, airway inflammation and symptoms, however, results were mixed and specific symptoms and potential underlying inflammatory mechanisms associated with exposure could not be identified. Large observational studies using well validated exposure assessment methods are needed to further our knowledge regarding the potential health effects of indoor (1-->3)-beta-D-glucan exposure.

PRACTICAL IMPLICATIONS

The currently available epidemiological data do not permit conclusions to be drawn regarding the presence (or absence) of an association between environmental (1-->3)-beta-D-glucan exposure and specific adverse health effects, nor is it clear from the currently available evidence which specific immunological mechanisms underlie the presumed health effects. More and larger observational studies are needed to asses whether (1-->3)-beta-D-glucan exposure plays a significant role in respiratory morbidity. In addition, existing methods to assess environmental (1-->3)-beta-D-glucan exposure require validation and further development before they can be used routinely in large scale epidemiological studies.

Exogenous nitric oxide can control SIRS and downregulate NFκB1,2

BACKGROUND

Nitric oxide (NO) participates in inflammation and affects almost all steps of its development. Several experimental studies have unveiled the beneficial effects of NO through modulation of the Systemic Inflammatory Response Syndrome (SIRS). In this sense, in the present work we attempted to evaluate the beneficial effects of exogenous NO and its levels of action (biochemical and cellular) in a model of SIRS induced by two sequential insults.

MATERIALS AND METHODS

Dacron graft implantation (first insult) and subsequent administration of Zymosan A (second insult) in Wistar rats. The animals were divided into four groups: 1) No manipulation (Basal); 2) Laparotomy (L) + mineral oil (Sham); 3) L + Graft-Zymosan (GZ) (Control); and 4) L + GZ + NO (Assay). Determinations: Survival, TNF-alpha, SOA, ICAM-1, and NFkappaB.

RESULTS

The model established (Control) induced a mortality rate of 20%. Also, it significantly increased the levels of TNF-alpha (P <0.001) and SOA (P <0.01), ICAM-1 expression, and NFkappaB levels (P <0.05). Treatment with NO reduced mortality to 0%, significantly decreasing TNF-alpha (P <0.001) and SOA (P <0.01) levels, ICAM-1 expression, and NFkappaB levels (P <0.05).

CONCLUSION

The exogenous administration of NO before the two sequential insults controlled SIRS at biochemical level (TNF-alpha, SOA) and at cellular level (transcription) in a lasting manner. The cascade-like interrelationship of both levels and the study design do not allow us the pinpoint the key to its modulation.

The effects of selective nitric oxide synthase blocker on survival, mesenteric blood flow and multiple organ failure induced by zymosan1

BACKGROUND

Circulatory failure in multiple organ dysfunction syndromes (MODS) is characterized with systemic vasodilation, diminished blood flow to various vascular beds. The aim of this study was to investigate the effects of selective inhibition of nitric oxide on the mesenteric arterial blood flow (MABF), survival and organ injury of the liver, kidney, lung and spleen in zymosan-induced MODS.

MATERIALS AND METHODS

Forty Swiss albino mice (20-40 g), 7 to 9 weeks old, were obtained. Animals were randomly divided into four groups. The first group were treated intraperitoneally (i.p) with vehicle (saline) and served as a sham group for aminoguanidine (AG) (n=10). The second group was treated with zymosan (500 mg/kg, suspended in saline solution, i.p). The mice in the third and fourth group received AG (15 mg/kg) 1 h and 6 h after zymosan or saline administration, respectively. Eighteen hours after the administration of zymosan, animals were assessed for MODS described subsequently. The signals from the flowmeter were also recorded on mesenteric arterial blood flow values.

RESULTS

In zymosan-treated animals, the MABF was significantly lower than that of solvent (saline)-treated controls (ml min(-1), controls: 4.6 +/- 0.6; zymosan: 1.6 +/- 0.9, P <0.05). When animals were treated with AG, there were no significant differences in MABF values between AG group and solvent (saline)-treated control group. However AG prevented zymosan-induced mesenteric MABF decrease. Treatment with aminoguanidine also decreased mortality.

CONCLUSION

AG is capable of inhibiting both the induction and the activity of the already iNOS; it remains a potential therapeutic agent in patients with MODS.

Diets containing barley significantly reduce lipids in mildly hypercholesterolemic men and women

BACKGROUND

Barley has high amounts of soluble fiber but is not extensively consumed in the US diet.

OBJECTIVE

This study investigated whether consumption of barley would reduce cardiovascular disease risk factors comparably with that of other sources of soluble fiber.

DESIGN

Mildly hypercholesterolemic subjects (9 postmenopausal women, 9 premenopausal women, and 7 men) consumed controlled American Heart Association Step 1 diets for 17 wk. After a 2-wk adaptation period, whole-grain foods containing 0, 3, or 6 g beta-glucan/d from barley were included in the Step 1 diet menus. Diets were consumed for 5 wk each and were fed in a Latin-square design. Fasting blood samples were collected twice weekly.

RESULTS

Total cholesterol was significantly lower when the diet contained 3 or 6 g beta-glucan/d from barley than when it contained no beta-glucan; the greatest change occurred in the men and postmenopausal women. HDL and triacylglycerol concentrations did not differ with the 3 amounts of dietary beta-glucan. Large LDL and small VLDL fractions and mean LDL particle size significantly decreased when whole grains were incorporated into the 3 diets. Large LDL and large and intermediate HDL fractions were significantly higher, mean LDL particle size was significantly greater, and intermediate VLDL fractions were significantly lower in the postmenopausal women than in the other 2 groups. A group-by-diet interaction effect was observed on LDL fractions and small LDL particle size.

CONCLUSION

The addition of barley to a healthy diet may be effective in lowering total and LDL cholesterol in both men and women.

Bioaerosols and innate immune responses in airway diseases

PURPOSE OF REVIEW

We review the role of bioaerosols in the pathogenesis of inflammatory airway disease. The focus is on recent discoveries in innate immune responses induced by common components of bioaerosols.

RECENT FINDINGS

Common components of bioaerosols include endotoxin, peptidoglycan and beta-glucan; all of which have been associated with inflammatory airway disease. Endotoxin signaling through toll-like receptor 4 is well characterized and updated. Peptidoglycan is now known to signal through three types of molecules: toll-like receptor 2; peptidoglycan recognition proteins; and nucleotide-binding oligomerization domain molecules. Beta-glucan, a common fungal cell wall component, signals through the newly discovered receptor, dectin-1. Emerging data indicate that genetic polymorphisms influence the response to bioaerosols.

SUMMARY

Activation of the innate immune system by bioaerosols is becoming better understood. This knowledge provides an opportunity to better prevent and treat airway diseases that result from environmental exposure.