epiglucan and Respiratory-Tract-Infections

The innate immune system responds in a rapid and non-specific manner against immunologic threats; inflammation is part of this response. This is followed by a slower but targeted and specific response termed the adaptive or acquired immune response. There is emerging evidence that dietary components, including yeast-derived β-glucans, can aid host defense against pathogens by modulating inflammatory and antimicrobial activity of neutrophils and macrophages. Innate immune training refers to a newly recognized phenomenon wherein compounds may "train" innate immune cells, such that monocyte and macrophage precursor biology is altered to mount a more effective immunological response. Although various human studies have been carried out, much uncertainty still exists and further studies are required to fully elucidate the relationship between β-glucan supplementation and human immune function. This review offers an up-to-date report on yeast-derived β-glucans as immunomodulators, including a brief overview of the current paradigm regarding the interaction of β-glucans with the immune system. The recent pre-clinical work that has partly decrypted mode of action and the newest evidence from human trials are also reviewed. According to pre-clinical studies, β-1,3/1,6-glucan derived from baker's yeast may offer increased immuno-surveillance, although the human evidence is weaker than that gained from pre-clinical studies.

Topics: Age Factors; Animals; Athletes; beta-Glucans; Glucans; Host-Pathogen Interactions; Humans; Immunity, Innate; Immunologic Factors; Lectins, C-Type; Respiratory Tract Infections

Topics: beta-Glucans; COVID-19; Dietary Supplements; Drugs, Chinese Herbal; Humans; Lactobacillus; Panax; Quercetin; Randomized Controlled Trials as Topic; Respiratory Tract Infections; SARS-CoV-2; Virus Diseases; Vitamin D; Vitamin D Deficiency

Yeast β-glucans are known for their immune-modulating effects; however, their effects on human upper respiratory tract infections (URTIs) remain unclear. The aim of the present study was to use a systematic review and meta-analysis approach to investigate the effects of yeast β-glucans for the prevention and treatment of URTIs in healthy subjects.. Databases including Pubmed, Web of Science, EMBASE and the Cochrane Library were searched and 13 RCTs investigating the effects of yeast β-glucans on the incidence, duration, and severity of URTIs in healthy subjects were included.. The results showed that compared to the placebo group, yeast β-glucan could significantly reduce the incidence of URTIs (OR = 0.345, 95% CI = 0.192 to 0.620, p < 0.001), decrease the average number of URTI episodes (SMD =  - 0.315, 95% CI =  - 0.500 to  - 0.130, p < 0.05), and decrease the duration of URTIs (SMD =  - 0.312, 95% CI =  - 0.561 to  - 0.064, p < 0.001). Improved severity of symptoms was found in yeast β-glucan group compared to the placebo group in the majority of included studies. In addition, yeast β-glucan was well tolerated and safe in general.. These findings suggest a positive effect of yeast β-glucans on human URTIs. However, due to the high heterogeneity and small number of included studies, more high-quality research and clinical trials are warranted.

Topics: beta-Glucans; Healthy Volunteers; Humans; Incidence; Respiratory Tract Infections; Saccharomyces cerevisiae

Respiratory tract infections (RTIs) are the most common form of infections in every age category. Recurrent respiratory tract infections (RRTIs), a specific form of RTIs, represent a typical and common problem associated with early childhood, causing high indirect and direct costs on the healthcare system. They are usually the consequence of immature immunity in children and high exposure to various respiratory pathogens. Their rational management should aim at excluding other severe chronic diseases associated with increased morbidity (e.g., primary immunodeficiency syndromes, cystic fibrosis, and ciliary dyskinesia) and at supporting maturity of the mucosal immune system. However, RRTIs can also be observed in adults (e.g., during exhausting and stressful periods, chronic inflammatory diseases, secondary immunodeficiencies, or in elite athletes) and require greater attention. Biologically active polysaccharides (e.g., β-glucans) are one of the most studied natural immunomodulators with a pluripotent mode of action and biological activity. According to many studies, they possess immunomodulatory, anti-inflammatory, and anti-infectious activities and therefore could be suggested as an effective part of treating and preventing RTIs. Based on published studies, the application of β-glucans was proven as a possible therapeutic and preventive approach in managing and preventing recurrent respiratory tract infections in children (especially β-glucans from

Topics: Athletes; beta-Glucans; Databases, Factual; Disease Management; Humans; Immunologic Factors; Pleurotus; Polysaccharides; Randomized Controlled Trials as Topic; Respiratory Tract Infections; Sports Medicine

Yeast-derived beta-glucans (Y-BG) are considered immunomodulatory compounds suggested to enhance the defense against infections and exert anticarcinogenic effects. Specific preparations have received Generally Recognized as Safe status and acceptance as novel food ingredients by European Food Safety Authority. In human trials, orally administered Y-BG significantly reduced the incidence of upper respiratory tract infections in individuals susceptible to upper respiratory tract infections, whereas significant differences were not seen in healthy individuals. Increased salivary IgA in healthy individuals, increased IL-10 levels in obese subjects, beneficial changes in immunological parameters in allergic patients, and activated monocytes in cancer patients have been reported following Y-BG intake. The studies were conducted with different doses (7.5-1500 mg/day), using different preparations that vary in their primary structure, molecular weight, and solubility. In animal models, oral Y-BG have reduced the incidence of bacterial infections and levels of stress-induced cytokines and enhanced antineoplastic effects of cytotoxic agents. Protective effects toward drug intoxication and ischemia/reperfusion injury have also been reported. In conclusion, additional studies following good clinical practice principles are needed in which well-defined Y-BG preparations are used and immune markers and disease endpoints are assessed. Since optimal dosing may depend on preparation characteristics, dose-response curves might be assessed to find the optimal dose for a specific preparation.

Topics: Administration, Oral; Animals; beta-Glucans; Humans; Interleukin-10; Respiratory Tract Infections; Yeasts

Using the evidence published over the last 2 years, this review discusses the epidemiology, diagnosis, treatment and prevention of HIV-related pulmonary infections other than mycobacterial disease.. Longstanding, vertically acquired and apparently stable HIV infection is associated with significant and symptomatic small airways disease in African adolescents. The use of population-based pneumococcal vaccination in children is changing the severity and serotypes associated with HIV-related pneumococcal disease. Data on the use of blood 1,3,β-D-glucan show it has promise as a rule-out test for Pneumocystis pneumonia (PCP).. With widespread antiretroviral medication usage, the pattern of HIV-associated pulmonary disease is changing. Whereas opportunistic infections such as PCP still occur in people not using antiretroviral therapy (ART), HIV-related infections are similar to those present in the general population. Chronic lung disease is more prevalent, leading to its own infectious complications. The use of specific immunizations against infections is important, though their precise benefit with concomitant widespread ART and population-based vaccination programmes in the non-HIV community is undetermined.

Topics: AIDS-Related Opportunistic Infections; Anti-Retroviral Agents; beta-Glucans; HIV Infections; Humans; Lung Diseases; Pneumococcal Infections; Respiratory Tract Infections

Prolonged and high-intensity exercise affects immune function and leads to an increased risk of upper respiratory tract infections (URTIs) in endurance athletes. The increased incidence of URTI symptoms may negatively affect athletic performance. Various nutritional supplements have been tested in the last decade for their ability to prevent developing of URTIs or reduce their incidence. One of the most promising nutritional supplements is β-glucan, a well-known immunomodulator with positive effects on functioning of immunocompetent cells. However, β-glucans are a diverse group of molecules that vary in macromolecular structure, solubility, viscosity, molecular weight and biological activity. This fact is supported by results from recent human clinical studies where β-glucans of different origin and properties differed in ability to prevent or reduce incidence of URTIs in athletes. It has been found that pleuran, a unique insoluble β-glucan isolated from mushroom Pleurotus ostreatus, significantly reduced the incidence of URTI symptoms in athletes. In addition, it was able to increase the number of circulating natural killer cells and to prevent reduction of natural killer cell activity. Contrarily, soluble oat β-glucan supplementation did not alter URTI incidence in endurance athletes. This difference suggests that the immunomodulatory capacity of β-glucans is strongly dependent on solubility and structural factors such as backbone structure and degree of branching. This review refers to using pleuran as a natural supplement that is able to protect endurance athletes against development of URTI.

Topics: beta-Glucans; Dietary Supplements; Exercise; Exercise Tolerance; Humans; Immune System; Immunologic Factors; Pleurotus; Respiratory Tract Infections; Risk Reduction Behavior; Time Factors

In this double-blind, randomized, placebo-controlled parallel study, we examined the effect of dairy-based beverages (250 mL/day) containing 250 mg of dispersible baker's yeast β-glucan (Wellmune) compared to a macronutrient- and calorie-matched control on upper respiratory tract infection (URTI) in marathon runners. Healthy adults running in the 2017 Austin Marathon consumed either β-glucan (

Topics: Adult; beta-Glucans; Beverages; Double-Blind Method; Female; Humans; Male; Middle Aged; Physical Conditioning, Human; Respiratory Tract Infections; Running; Self Report; Symptom Assessment; Texas; Yeast, Dried

Each year, adults suffer about two to four upper respiratory tract infections (URTIs), mostly in winter. The aim of the study was to evaluate the effects of brewers' yeast (1,3)-(1,6)-beta-glucan on incidence and severity of upper respiratory tract infections (URTIs).. Generally healthy men and women (n = 299) reporting at least three URTIs during the previous year were randomized to receive either a placebo or 900 mg of yeast beta-glucan daily for 16 weeks during winter. In cases of acute URTI, the severity of URTI symptoms was assessed via the WURSS-21 questionnaire and the Jackson scale, and a clinical confirmation was implemented by the investigator.. Overall, 70 subjects under placebo and 71 subjects under yeast beta-glucan experienced at least one clinically confirmed URTI episode. The global severity using WURSS-21 had been quite similar between the study groups (p = 0.5267), whereas during the first days of URTIs the severity was less pronounced in the yeast beta-glucan group. On the episode level, the severity of physical symptoms was significantly lower for all investigated time intervals up to 7 days under yeast beta-glucan (WURSS (Q2-11) (days 1-2: p = 0.0465, days 1-3: p = 0.0323, days 1-4: p = 0.0248, days 1-7: p = 0.0278), also confirmed for the Jackson scale). The reduction of severity was accompanied by a significant increase in the joy subscore of the Perceived Stress Questionnaire (PSQ20) (p = 0.0148). In addition, there was a reduction of systolic (p = 0.0458) and diastolic (p = 0.1439) blood pressure.. Subjects supplementing with yeast beta-glucan benefit by a reduced severity of physical URTI symptoms during the first week of an episode, even though the incidence and global severity of common colds could not be altered in comparison to placebo. Furthermore, accompanying benefits in terms of blood pressure and mood were identified. Altogether, yeast beta-glucan supports the immune function.

Topics: Adult; beta-Glucans; Dietary Supplements; Double-Blind Method; Female; Healthy Volunteers; Humans; Incidence; Male; Middle Aged; Respiratory Tract Infections; Severity of Illness Index; Yeast, Dried; Young Adult

Nutrients such as docosahexaenoic acid (DHA), prebiotics and β-glucan have been associated with reduced incidence of respiratory illnesses and allergic manifestations (AM). Our objective was to assess if consumption of a cow's milk-based beverage with these and other nutrients supports respiratory, gastrointestinal, and skin health in otherwise well-nourished, healthy children.. In this double-blind, randomized, controlled trial, healthy children (1-4 years of age) from two daycare centers in Brazil were fed three servings/day of a cow's milk-based beverage (CMBB; n = 125) containing DHA, the prebiotics polydextrose (PDX) and galactooligosaccharides (GOS), β-glucan, and other key nutrients, or a control cow's milk-based beverage (control; n = 131) for up to 28 weeks. Occurrence of respiratory infections, diarrheal disease and AM was assessed by study pediatricians and the number of episodes were analyzed with the Cochran-Mantel-Haenszel test and the Andersen-Gill model.. The CMBB group had fewer episodes of AM, which included allergic rhinitis or conjunctivitis, wheezing, allergic cough, eczema and urticaria, compared to the control group (p = 0.021). The hazard ratio for increased number of episodes of AM was lower in the CMBB group compared to control (HR, 0.64; 95 % CI 0.47-0.89; p = 0.007). There was no difference in the incidence of respiratory infections and diarrheal disease between groups.. A cow's milk-based beverage containing DHA, PDX/GOS, and yeast β-glucan, and supplemented with micronutrients, including zinc, vitamin A and iron, when consumed 3 times/day for 28 weeks by healthy 1- to 4-year-old children was associated with fewer episodes of allergic manifestations in the skin and the respiratory tract.. registration number: NCT01431469.

Topics: Animals; beta-Glucans; Beverages; Biomarkers; Brazil; Child, Preschool; Diarrhea; Dietary Supplements; Docosahexaenoic Acids; Double-Blind Method; Female; Follow-Up Studies; Humans; Hypersensitivity; Incidence; Infant; Interleukin-10; Male; Micronutrients; Milk; Prebiotics; Prospective Studies; Respiratory Tract Infections; Socioeconomic Factors; Transforming Growth Factor beta1; Treatment Outcome; Trisaccharides

Recurrent respiratory tract infections (RRTIs) present a very important problem in paediatric praxis. As true immunodeficiencies are rare, one of the most important factors assumed to contribute to increased respiratory morbidity is atopy. Several preparations of natural origin have been used for the prevention of RRTIs, and some of the most effective immunomodulators are biologically active polysaccharides - e.g. ß-glucans. In our randomised, double-blind, placebo-controlled study, we investigated the prevalence of atopy in a group of children with RRTIs and the potential anti-allergic effect of pleuran (ß-glucan isolated from Pleurotus ostreatus) on basic laboratory markers of allergic inflammation. We confirmed that atopy may be an important factor contributing to the increased respiratory morbidity in children with RRTIs. The active treatment with pleuran resulted in a significant reduction of peripheral blood eosinophilia and stabilised the levels of total IgE in serum. This was more evident in atopic subjects. Pleuran showed a potential anti-allergic effect. This previously non-described effect could expand the application of this natural immunomodulator also as a complementary adjuvant therapy in allergic patients.

Topics: Anti-Allergic Agents; beta-Glucans; Child; Child, Preschool; Double-Blind Method; Eosinophilia; Female; Humans; Hypersensitivity, Immediate; Immunoglobulin E; Male; Pleurotus; Respiratory Tract Infections

Recurrent respiratory infections (RRI), such as the presence of at least one of the following criteria: i) >6 RI per year; ii) >1 RI per month involving upper airways from September to April; iii) >3 RI involving lower airways, constitute a social problem for both their pharmaco-economic impact and the burden for the family. However, several treatment have been proposed with controversial results.. As resveratrol plus carboxymethyl-β-glucan is presently available as solution for aerosol, the aim of this study was to evaluate the effects of this compound, compared to saline solution, whether it is able to prevent RRI in children.. The study was designed as real-life, randomized. Globally, 82 children (49 males, mean age 8.1 ± 2.6 years) with acute rhinopharyngitis and RRI were enrolled. Resveratrol plus carboxymethyl-β-glucan or saline isotonic solution was randomly (ratio 1:1) administered immediately after an anti-infective and anti-inflammatory 10-day treatment (tiamphenicol associated with acetylcysteine plus beclomethasone dipropionate) for the acute rhinopharyngitis. Investigated treatments lasted 20 days. Days with respiratory symptoms, fever, medication use, medical visits, and school absences were evaluated. Children were visited 30, 60, and 90 days after starting treatments.. The active compound was able to significantly reduce the number of days with nasal obstruction (p < 0.001), rhinorrhea (p < 0.001), sneezing (p < 0.001), cough (p = 0.002), fever (p < 0.001), medication use (p < 0.001), medical visits (p < 0.001), and school absence (p < 0.001).. This preliminary and real-life study could suggest that an aerosolized solution containing resveratrol plus carboxymethyl-β-glucan might exert preventive effects in children with RRI.

Topics: Anti-Inflammatory Agents, Non-Steroidal; beta-Glucans; Child; Cytarabine; Drug Therapy, Combination; Female; Follow-Up Studies; Humans; Life Change Events; Male; Recurrence; Respiratory Tract Infections; Resveratrol; Stilbenes; Treatment Outcome; Vasodilator Agents

Recurrent respiratory tract infections (RRTIs) represent a very important problem in daily clinical practice because of their significant contribution to morbidity in children. Several natural nutritional supplements have been used in the prevention of RRTIs, but the clinical efficacy of only a few preparations is supported by scientific evidence.. In a double-blind, placebo-controlled, randomised, multicentre study, we have observed a group of 175 children (aged 5.65 ± 2.39 years) with more than 5 respiratory infections that occurred during the 12 months prior to the beginning of the study. Children were randomised into an active group, treated with Imunoglukan P4H® syrup (with pleuran-β-glucan from Pleurotus ostreatus and vitamin C), or a placebo group (vitamin C only). During the 3 visits, within a 12-month period, questionnaires were completed, and blood samples were examined for immune parameters.. In the active group, 36% of the children did not suffer from any respiratory infections throughout the treatment, compared to 21% in the placebo group (p<0.05). Imunoglukan P4H® also significantly decreased the frequency of flu and flu-like disease and the number of lower respiratory tract infections. Imunoglukan P4H® treatment resulted in a statistically significant modulation of humoral and cellular immunity.. Results from this study demonstrate that Imunoglukan P4H® is effective in the prevention of RRTIs in children. Furthermore, our results also revealed complex immunomodulatory activity of this product. This is the first double-blind, placebo-controlled study in children with RRTIs that has addressed the preventive effects of pleuran on morbidity caused by respiratory infections.

Topics: Adjuvants, Immunologic; beta-Glucans; Child; Child, Preschool; Female; Follow-Up Studies; Humans; Immunoglobulin G; Immunomodulation; Immunophenotyping; Male; Pleurotus; Recurrence; Respiratory Tract Infections; T-Lymphocytes

Wellmune WGP is a food supplement containing a refined 1,3/1,6 glucopolysaccharide that improves the antimicrobial activity of the innate immune cells by the priming of lectin sites. This study aimed to investigate whether Wellmune decreases the frequency and severity of upper respiratory tract infection (URTI) symptoms over 90 d during the peak URTI season in healthy university students. The secondary aims included an assessment of plasma cytokine and chemokine levels.. This was a randomized, double-blinded, placebo-controlled trial lasting 90 d. One hundred healthy individuals (18-65 y old, mean age ~21 y) were randomized to 250 mg of Wellmune once daily or to an identical rice flour-based placebo. Health was recorded daily and two or more reported URTI symptoms for 2 consecutive days triggered a medical assessment and blood collection within 24 h. The URTI symptom severity was monitored. Plasma cytokines and chemokines were measured at day 0, day 90, and during the confirmed URTI.. Ninety-seven participants completed the trial (Wellmune, n = 48; placebo, n = 49). The Wellmune tended to decrease the total number of days with URTI symptoms (198 d, 4.6%, versus 241 d, 5.5% in the control group, P = 0.06). The ability to "breathe easily" was significantly improved in the Wellmune group; the other severity scores showed no significant difference. Cytokines and chemokines were not different between the groups at study entry or day 90, but monocyte chemotactic protein-1 was lower in the Wellmune group during the URTI.. Wellmune may decrease the duration and severity of URTI. Larger studies are needed to demonstrate this.

Topics: Adolescent; Adult; beta-Glucans; Biological Products; Chemokine CCL2; Cytokines; Dietary Supplements; Double-Blind Method; Female; Humans; Male; Respiration; Respiratory Tract Infections; Severity of Illness Index; Students; Yeasts; Young Adult

Several studies have shown a baker's yeast beta-1,3/1,6-d-glucan, extracted from Saccharomyces cerevisiae, is effective in reducing the incidence of cold and flu symptoms. This study evaluated the effect of a specific beta-glucan supplement (Wellmune) on upper respiratory tract symptoms and psychological well-being in women with moderate levels of psychological stress.. Healthy women (38 ± 12 years old) prescreened for moderate levels of psychological stress, self-administered a placebo (n = 38) or 250 mg of Wellmune (n = 39) daily for 12 weeks. We used the Profile of Mood States (POMS) psychological survey to assess changes in mental/physical energy levels (vigor) and overall well-being (global mood state). A quantitative health perception log was used to track upper respiratory symptoms.. Subjects in the Wellmune group reported fewer upper respiratory symptoms compared to placebo (10% vs 29%), better overall well-being (global mood state: 99 ± 19 vs 108 ± 23, p < 0.05), and superior mental/physical energy levels (vigor: 19.9 ± 4.7 vs 15.8 ± 6.3, p < 0.05).. These data show that daily dietary supplementation with Wellmune reduces upper respiratory symptoms and improves mood state in stressed subjects, and thus it may be a useful approach for maintaining immune protection against daily stressors.

Topics: Adult; Affect; beta-Glucans; Dietary Supplements; Double-Blind Method; Female; Humans; Incidence; Influenza, Human; Respiratory Tract Infections; Saccharomyces cerevisiae; Stress, Psychological; Surveys and Questionnaires

Prolonged and exhausting physical activity causes numerous changes in immunity and sometimes transient increases the risk of upper respiratory tract infections (URTIs). Nutritional supplements as countermeasures to exercise-induced changes have increasingly been studied in the last decade. One of the most promising nutritional supplements is β-glucan, a well-known immunomodulator with positive effects on the function of immunocompetent cells. In this double blind, placebo-controlled study, we investigated the effect of pleuran, an insoluble β-(1,3/1,6) glucan from mushroom Pleurotus ostreatus, on selected cellular immune responses and incidence of URTI symptoms in athletes. Fifty athletes were randomized to pleuran or placebo group, taking pleuran (commercial name Imunoglukan(®)) or placebo supplements during 3 months. Venous whole blood was collected before and after 3 months of supplementation and additionally 3 months after supplementation period was completed. Incidence of URTI symptoms together with characterization of changes in phagocytosis and natural killer (NK) cell count was monitored during the study. We found that pleuran significantly reduced the incidence of URTI symptoms and increased the number of circulating NK cells. In addition, the phagocytosis process remained stable in pleuran group during the study in contrast to placebo group where significant reduction of phagocytosis was observed. These findings indicate that pleuran may serve as an effective nutritional supplement for athletes under heavy physical training. Additional research is needed to determine the mechanisms of pleuran function.

Topics: Adjuvants, Immunologic; Adult; Athletes; beta-Glucans; Dietary Supplements; Double-Blind Method; Female; Humans; Immunity, Cellular; Incidence; Male; Placebos; Pleurotus; Respiratory Tract Infections; Young Adult

Nasal congestion is the main symptom in common upper respiratory diseases in childhood. Intranasal administration of sympatheticomimetics decongestants is commonly adopted for this symptom. The Italian Drug Agency stated a warning against the use of these drugs in children under 12 years of age. The aim of this study is to evaluate the efficacy on nasal symptoms and the safety of a new medical device based on colloidal silver and carbossimetyl beta glucan compared with saline solution treatment in a group of children (0-12 years) affected by viral rhinitis.. Hundred consecutive outpatient children (0-12 year old), affected by common cold syndrome with evident nasal obstruction were randomly assigned to two type of intervention: group 1. receiving colloidal silver and carbossimetyl beta glucan; group 2. receiving saline solution. Each subject underwent clinical history and objective examination of rhinosinusal district at enrollment. Upper respiratory pathologie-related symptoms were specifically evaluated by using the Canadian Acute Respiratory Illness and Flu Scale (CARIFS).. A significant improvement of CARIFS score was observed into the two groups. The score improvement of these two treatment was confirmed in all the age sub-group. We observed a statistically significant difference in mean post-treatment CARIFS score and CARIFS globas VAS (Visual Analogic Scale) in children of group 1 compared with children in group 2 (2.28 ± 1.58 vs. 5.08 ± 3.39; P<0.001 and VAS: 1.87 ± 1.38 vs. VAS: 3.34 ± 2.19; P=0.012, respectively). At the end of treatment, 90% of subjects in group 1 resulted completely recovered, whereas 10% experienced some degree of complications (otitis, tracheitis, bronchitis). In group 2 a complete recovering was achieved in 66 % of subjects, the remaining 34 % developed complications. Tolerability profiles were similar in the two groups with no statistical differences in side effects in all age subgroups.. Despite both treatments reached significative improvements in CARIFS global score and VAS and in physical examination of nasal mucosa and secretion at the end of the therapy, colloidal silver and carbossimetyl beta glucan showed a better performance with a significant difference in mean post-treatment CARIFS global score and CARIFS VAS compared to treatment with saline solution.

Topics: beta-Glucans; Child; Child, Preschool; Colloids; Humans; Infant; Nasal Obstruction; Prospective Studies; Respiratory Tract Infections; Rhinitis; Severity of Illness Index; Silver Compounds

This study investigated the effects of oat beta-glucan (BG) supplementation on chronic resting immunity, exercise-induced changes in immune function, and self-reported upper respiratory tract infection (URTI) incidence in human endurance athletes.. Trained male cyclists were randomized to BG (N = 19) or placebo (P; N = 17) groups and under double-blind procedures received BG (5.6 g x d(-1)) or P beverage supplements for 2 wk before, during, and 1 d after a 3-d period in which subjects cycled for 3 h x d(-1) at approximately 57% maximal watts. URTI symptoms were monitored during BG supplementation and for 2 wk afterward. Blood samples were collected before and after 2 wk of supplementation (both samples, 8:00 a.m.), immediately after the 3-h exercise bout on day 3 (6:00 p.m.), and 14 h after exercise (8:00 a.m.) and were assayed for natural killer cell activity (NKCA), polymorphonuclear respiratory burst activity (PMN-RBA), phytohemagglutinin-stimulated lymphocyte proliferation (PHA-LP), plasma interleukin 6 (IL-6), IL-10, IL-1 receptor agonist (IL-1ra), and IL-8, and blood leukocyte IL-10, IL-8, and IL-1ra mRNA expression.. Chronic resting levels and exercise-induced changes in NKCA, PMN-RBA, PHA-LP, plasma cytokines, and blood leukocyte cytokine mRNA did not differ significantly between BG and P groups. URTI incidence during the 2-wk postexercise period did not differ significantly between groups.. An 18-d period of BG versus P ingestion did not alter chronic resting or exercise-induced changes in immune function or URTI incidence in cyclists during the 2-wk period after an intensified exercise.

Topics: beta-Glucans; Dietary Supplements; Double-Blind Method; Exercise Test; Humans; Immune System; Male; Physical Exertion; Respiratory Tract Infections; Sports

Oat beta-glucan can counteract the exercise-induced increased risk for upper respiratory tract infection (URTI) in mice, which is at least partly mediated by its effects on lung macrophages. Substantial evidence in humans indicates that carbohydrate-containing sports drinks can offset the decreased immune function associated with stressful exercise. However, no studies in animals or humans have directly examined their effects on URTI using a controlled virus-challenge model. We examined the effects of sucrose feedings alone and in combination with oat beta-glucan on susceptibility to infection and on macrophage antiviral resistance in mice following stressful exercise. These effects were also examined in rested, nonimmunocompromised control mice. Mice were assigned to one of four groups: H(2)O (water), sucrose (S), oat beta-glucan (ObetaG), and sucrose + oat beta-glucan (S+ObetaG). ObetaG and S treatments consisted of a solution of 50% ObetaG and 6% sucrose, respectively, and were administered in drinking water for 10 consecutive days. Exercise consisted of a treadmill run to fatigue performed on three consecutive days. Mice were then intranasally inoculated with a standardized dose of herpes simplex virus 1 (HSV-1) and monitored for morbidity and mortality for 21 days. Additional mice were used to determine macrophage antiviral resistance. In the exercise experiment, S, ObetaG, and S+ObetaG all reduced morbidity (P < 0.05), while only S+ObetaG reduced mortality (P < 0.05). Macrophage antiviral resistance was also increased in S, ObetaG, and S+ObetaG treatments (P < 0.05). In resting controls, S and S+ObetaG reduced morbidity and mortality (P < 0.05) and showed a trend toward increased macrophage antiviral resistance. There was no significant additive effect of S and ObetaG in either control or exercised animals. These data extend our previous work on the benefits of oat beta-glucan to show that sucrose feedings have similar effects on susceptibility to respiratory infection and macrophage antiviral resistance in both resting controls and following exercise stress.

Topics: Animal Nutritional Physiological Phenomena; Animals; Avena; beta-Glucans; Blood Glucose; Body Weight; Dietary Sucrose; Disease Models, Animal; Herpes Simplex; Herpesvirus 1, Human; Macrophages; Male; Mice; Muscle Fatigue; Physical Exertion; Respiratory Tract Infections; Stress, Physiological; Time Factors

Exercise stress is associated with an increased risk for upper respiratory tract infection (URTI). We have shown that consumption of the soluble oat fiber beta-glucan (ObetaG) can offset the increased risk for infection and decreased macrophage antiviral resistance following stressful exercise; however, the direct role of macrophages is unknown. This study examined the effect of macrophage depletion on the benefits of orally administered ObetaG on susceptibility to infection (morbidity, symptom severity, and mortality) following exercise stress. CL(2)MDP (Ex- H(2)O-CL(2)MDP, Ex-ObetaG-CL(2)MDP, Con-H(2)O-CL(2)MDP, Con-ObetaG-CL(2)MDP)-encapsulated liposomes were administered intranasally to deplete macrophages, and PBS (Ex-H(2)O-PBS, Ex-ObetaG-PBS, Con-H(2)O-PBS, Con-ObetaG-PBS)-encapsulated liposomes were given to macrophage-intact groups. Ex mice ran to volitional fatigue on a treadmill for 3 consecutive days, and ObetaG mice were fed a solution of 50% ObetaG in their drinking water for 10 consecutive days before infection. Fifteen minutes following the final bout of Ex or rest, mice were intranasally inoculated with 50 microl of a standardized dose of herpes simplex virus-1. Ex increased morbidity (P < 0.001) and symptom severity (P < 0.05) but not mortality (P = 0.09). The increase in morbidity and symptom severity was blocked by ObetaG consumption for 10 consecutive days before exercise and infection [morbidity (P < 0.001) and symptom severity (P < 0.05)]. Depletion of macrophages negated the beneficial effects of ObetaG on reducing susceptibility to infection following exercise stress, as evidenced by an increase in morbidity (P < 0.01) and symptom severity (P < 0.05). Results indicate that lung macrophages are at least partially responsible for mediating the beneficial effects of ObetaG on susceptibility to respiratory infection following exercise stress.

Topics: Analgesics, Non-Narcotic; Animal Nutritional Physiological Phenomena; Animals; Avena; beta-Glucans; Clodronic Acid; Diet; Herpes Simplex; Herpesvirus 1, Human; Immunity, Cellular; Liposomes; Lung; Macrophages; Male; Mice; Muscle Fatigue; Physical Conditioning, Animal; Respiratory Tract Infections; Stress, Physiological; Weight Gain

Inuit infants have extremely high rates of lower respiratory tract infection (LRTI), but the causes for this are unclear. The aims of this study were to assess, in young Inuit children in Baffin Region, Nunavut, the feasibility of an epidemiologic study of the association between indoor air quality (IAQ) and respiratory health; to obtain data on IAQ in their housing; and to identify and classify risk factors for LRTI. Twenty houses in Cape Dorset, Nunavut with children below 2 years of age, were evaluated using a structured housing inspection and measurement of IAQ parameters, and a respiratory health questionnaire was administered. Twenty-five percent of the children had, at some time, been hospitalized for chest illness. Houses were very small, and had a median of six occupants per house. Forty-one percent of the houses had a calculated natural air change rate <0.35 air changes per hour. NO(2) concentrations were within the acceptable range. Smokers were present in at least 90% of the households, and nicotine concentrations exceeded 1.5 microg/m(3) in 25% of the dwellings. Particulates were found to be correlated closely with nicotine but not with NO(2) concentrations, suggesting that their main source was cigarette smoking rather than leakage from furnaces. Mattress fungal levels were markedly increased, although building fungal concentrations were low. Dust-mites were virtually non-existent. Potential risk factors related to IAQ for viral LRTI in Inuit infants were observed in this study, including reduced air exchange and environmental tobacco smoke exposure. Severe lower respiratory tract infection is common in Inuit infants. We found reduced air change rates and high occupancy levels in houses in Cape Dorset, which may increase the risk of respiratory infections. This suggests the measures to promote better ventilation or more housing may be beneficial. Further health benefits may be obtained by reducing bed sharing by infants and greater turnover of mattresses, which were found to have high levels of fungi.

Topics: Air Pollutants; Air Pollution, Indoor; Antigens, Dermatophagoides; Arthropod Proteins; beta-Glucans; Carbon Dioxide; Cysteine Endopeptidases; Dust; Endotoxins; Female; Fungi; Housing; Humans; Humidity; Infant; Inuit; Male; Nicotine; Nitrogen Dioxide; Nunavut; Respiratory Tract Infections; Risk Factors; Temperature; Tobacco Smoke Pollution; Yeasts

Both moderate exercise and the soluble oat fiber beta-glucan can increase immune function and decrease risk of infection, but no information exists on their possible combined effects. This study tested the effects of moderate exercise and oat beta-glucan on respiratory infection, macrophage antiviral resistance, and natural killer (NK) cell cytotoxicity. Mice were assigned to four groups: exercise and water, exercise and oat beta-glucan, control water, or control oat beta-glucan. Oat beta-glucan was fed in the drinking water for 10 days before intranasal inoculation of herpes simplex virus type 1 (HSV-1) or euthanasia. Exercise consisted of treadmill running (1 h/day) for 6 days. Macrophage resistance to HSV-1 was increased with both exercise and oat beta-glucan, whereas NK cell cytotoxicity was only increased with exercise. Exercise was also associated with a 45 and 38% decrease in morbidity and mortality, respectively. Mortality was also decreased with oat beta-glucan, but this effect did not reach statistical significance. No additive effects of exercise and oat beta-glucan were found. These data confirm a positive effect of both moderate exercise and oat beta-glucan on immune function, but only moderate exercise was associated with a significant reduction in the risk of upper respiratory tract infection in this model.

Topics: Animal Nutritional Physiological Phenomena; Animals; Avena; beta-Glucans; Cytotoxicity, Immunologic; Disease Susceptibility; Glucans; Herpes Simplex; HIV-1; Immune System; Incidence; Killer Cells, Natural; Macrophages, Peritoneal; Male; Mice; Mice, Inbred Strains; Motor Activity; Respiratory Tract Infections; Tumor Necrosis Factor-alpha; Weight Gain

Topics: Air Pollutants, Occupational; beta-Glucans; Endotoxins; Environmental Monitoring; Garbage; Glucans; Humans; Occupational Diseases; Occupational Exposure; Refuse Disposal; Respiratory Tract Infections