Effect Of Glucan Research Articles

The influence of different types of ß-glucans on the gut microbiota of rats fed milk gels

• The frequency of Bacteroides depends on the acidity of the product. • Body weight gain was significantly correlated with the abundance of Streptococcus sp. • β-glucans resulted in a decrease in Lactobacillus frequency. • Oat ß-glucan contributed to a higher Clostridium sensu stricto and Blautia counts. The effect of glucans on gut microbiota functions is still unclear. Therefore, this study was undertaken to describe the influence of structurally different ß-glucans (oat ß-glucan, curdlan and scleroglucan) on the structure of the gut microbiome in rats. The structure of intestinal microbiota was evaluated by high-throughput sequencing of the16S rRNA gene. Firmicutes and Bacteroidetes were the dominant bacterial phyla in all animals. Oat ß-glucan contributed to a higher prevalence of bacterial genera Clostridium sensu stricto and Blautia , whereas curdlan increased the relative abundance of Akkermansia muciniphila. A positive correlation was noted between the relative abundance of Streptococcus bacteria and the growth rate of rats. The present study demonstrated that the consumption of non-acidified milk gels or acidified milk gels with a β-glucan dose recommended by EFSA (3.0–4.0 g per day) for 28 days did not induce significant changes in the structure of the gut microbiome in rats.

Chiral Cellulose Nanocrystal Humidity-Responsive Iridescent Films with Glucan for Tuned Iridescence and Reinforced Mechanics.

The fabrication of biomimetic photonic materials with environmental stimuli-responsive functions from entirely biobased materials is becoming increasingly challenging with the growing demand for biodegradable materials. Herein, the effect of glucan with different molecular weights on the mechanical performance and tunable structural color of iridescent CNC composite films was investigated. The existence of glucan did not influence the self-assembly performance of CNCs, but rather led to an improvement in the mechanical performance, enabling cholesteric CNC composite films with an adjustable structural color. Simultaneously, the iridescent films showed a conspicuous redshift and enlarged initial pitch without obstruction of the chiral structure. In response to environmental humidity, the structural colors of the iridescent composite films can be changed by regulating their chiral nematic structure. In particular, the films demonstrate a reversible structural color change between blue and red at RH between 50 and 98%. The resulting biobased iridescent composite films have potential applications in decorative coating, optical and humidity sensing, and anticounterfeiting.

A Report on Fungal (1→3)-α-d-glucans: Properties, Functions and Application.

The cell walls of fungi are composed of glycoproteins, chitin, and α- and β-glucans. Although there are many reports on β-glucans, α-glucan polysaccharides are not yet fully understood. This review characterizes the physicochemical properties and functions of (1→3)-α-d-glucans. Particular attention has been paid to practical application and the effect of glucans in various respects, taking into account unfavourable effects and potential use. The role of α-glucans in plant infection has been proven, and collected facts have confirmed the characteristics of Aspergillus fumigatus infection associated with the presence of glucan in fungal cell wall. Like β-glucans, there are now evidence that α-glucans can also stimulate the immune system. Moreover, α-d-glucans have the ability to induce mutanases and can thus decompose plaque.

IgG4-Related orbital disease in patients with diabetic retinopathy: Effects of glucan and vitamin D supplementation

Abstract Background: Diabetic retinopathy represents a serious complication of diabetes. Methods: In our group of 52 patients, we identified 7 individuals (13%) with elevated levels of

A Novel Glucan-Sulforaphane Combination Stimulates Immune Response to Influenza in Mouse Model

Influenza remains a serious health problem and causes approximately 500,000 deaths world-wide. With current available treatments offering neither dependable protection nor a rapid cure, many have focused their attention to alternative treatments. The aim of this study was to evaluate the possible effect of a novel maitake glucan-sulforaphane combination on immune response against influenza challenge in mice. We evaluated the effects of a glucan-sulforaphane combination on basic immune reactions, virus titre and overall survival after influenza infection. Results: We found 2 weeks supplementation with this glucan-sulforaphane combination significantly improved immunosuppression caused by the viral infection. Based on these results, we conclude that the significant immunostimulation caused by this combination helps to overcome virus-dependent suppression of defense reactions and that addition of sulforaphane to glucan can improve already established biological effects of glucan.

Effect of β-glucan Supplementation on Levels of IgM, IgA, IgG and Its Subclasses IgG1, IgG2, IgG3, and IgG4 in Cancer Patients

AIM: The role of β-glucan supplementation on cancer development is well established. In this report we focused on the effects of glucan on levels of individual classes and subclasses of immunoglobulins. MATERIALS AND METHODS: We evaluated the levels of IgM, IgG, IgA, IgG1, IgG2, IgG3 and IgG4 in 39 patients diagnosed with breast or colorectal cancer. RESULTS: We found a significant decrease of IgG1 levels in the placebo group, which was particularly pronounced in females. CONCLUSIONS: Short-term glucan supplementation significantly stabilized levels of IgG1 resulting in maintaining anti-infectious immunity. The decrease in IgG1 levels found in the placebo group was clearly caused by a complex therapy of cancer disease.

Effect of Glucan and Low Doses of T-2 Toxin on Mucin, IgA Expression and IgA+ Lymphocytes in the Intestine of Chickens

Effect of Glucan and Low Doses of T-2 Toxin on Mucin, IgA Expression and IgA+ Lymphocytes in the Intestine of Chickens

The influence of a glucosyltransferase, encoded by gtfP, on biofilm formation by Streptococcus sanguinis in a dual‐species model

Streptococcus sanguinis is an early colonizer of tooth surfaces and forms biofilms with other species of microorganisms. In vitro, S. sanguinis produces water-soluble glucans from sucrose and releases them into the culture supernatant; however, the role played by these glucans in biofilm formation is unclear. The present study examined both the effect of glucans on biofilm formation by S. sanguinis and the proportion of this bacterial species within the biofilms. Inactivation of the gtfP gene, annotated as glucosyltransferase in the S. sanguinis genome database, caused a marked reduction in the amount of water-soluble glucans in the culture supernatant, but not in the amount of water-insoluble glucans expressed on the bacterial cell surface. Scanning electron microscopy revealed that wild-type S. sanguinis, but not the gtfP-deficient mutant, produced large amounts of sticky material in the presence of 1% (w/v) sucrose. In addition, biofilm production by wild-type bacteria was greater than that by the mutant strain. By contrast, co-culture of mutant bacteria with Streptococcus mutans, S. sobrinus, S. oralis, S. gordonii, S. anginosus, or S. salivarius showed that inactivating the gtfP gene had little effect on the amount of biofilm produced. Furthermore, inactivating the gtfP gene did not greatly alter the proportion of S. sanguinis in the biofilms formed by the co-cultures. Thus, despite the role of S. sanguinis glucosyltransferase in formation of water-soluble glucans and biofilms in monoculture, the functional gene contributed little to biofilms in co-culture experiments.

Effects of glucan on bone marrow.

Bone marrow damage represents a significant problem in cancer treatment. Therefore, it is clear that the pharmacologic protection against bone marrow damage is of considerable interest, since the development of novel and effective medical approaches to combat radiation or cytotoxic damage are of major importance not only to the medical field but also to several industries and the military. This review represents a summary of our knowledge of the effects of various glucans on bone marrow protection.

Effects of glucans and eicosapentaenoic acid on differential regulation of phenylpropanoid and mevalonic pathways during potato response to Phytophthora infestans

The effects of Phytophthora infestans glucans, eicosapentaenoic acid (EPA) and isolates of this pathogen, on the differential expression of eight genes from the phenylpropanoid and the mevalonate (Ac-MVA) pathways were analyzed in potato by semi-quantitative RT-PCR and qRT-PCR. The application of EPA had an elicitor effect in Russet Burbank (RB) and Defender (DF) in response to inoculation with a US8 isolate of P.infestans, thereby reducing symptoms of late blight. Such effect was associated with the expression of PAL-1 and PAL-2, since the latter occurred only when EPA was followed by inoculation, whereas these genes were down-regulated in individual treatments RB+EPA, RB+US8, DF+EPA, and DF+US8. The glucan fraction did not by itself suppress phenylpropanoid genes, but its combination with the pathogen resulted in a down-regulation of PAL-1, PAL-2 and CHS. The addition of the glucan fraction to the elicitor EPA, had a negative effect (RB+EPA+GL+US8) since plants showed higher disease symptoms than the ones pretreated with water then infected with US8, and in comparison with RB+EPA+US8 and RB+GL+US8. Exclusive up-regulation of 4CL in DF+US11 and of CHS in DF+EPA+GL+US8, DF+EPA+US11, DF+GL+US11 and DF+EPA+GL+US11, where late blight lesions were not detected, could be associated with potato protection against late blight. Along with previous findings in this pathosystem, these data suggest that genetic resistance in potato against P.infestans is not the result of isolated reactions against the pathogen, but rather the combination of many factors in-line with a polygenic/horizontal resistance.

Effects of Glucan on Immunosuppressive Actions of Mercury

Global cycling of mercury results in the presence of mercury salts in the environment. The well-established negative effects of mercury on the immune system led us to the study whether natural immunomodulator glucan can overcome the immunosuppressive effects of mercury. Two types of mercury, thimerosal and mercury acetate, were administered in a dose of 2-8 mg/L of drinking water to mice. After 2 weeks, all mice exhibited profound suppression of both cellular (phagocytosis, natural killer cell activity, mitogen-induced proliferation, and expression of CD markers) and humoral (antibody formation and secretion of interleukin-6, interleukin-12, and interferon-gamma) responses. The mice were then fed with a diet containing a standard dose of glucan. Our results showed that simultaneous treatment with mercury and glucan resulted in significantly lower immunotoxic effects of mercury, which suggests that glucans can be successfully used as a natural remedy of low-level exposure to mercury.

The Effect of β-Glucan on Trace Element Levels in Intra-Abdominal Sepsis in Rats

Sepsis is associated with the development of progressive damage in multiple organ systems. The beneficial effect of glucans has been attributed to modulation of immune function and enhances defense against bacterial, viral, fungal, and parasitic infections. The aim of this study was to investigate the putative protective effect of ß-glucan on changes of trace element levels in various tissues after experimental sepsis in rats. Sepsis was induced by cecal ligation and perforation (CLP) in 28 male Wistar albino rats. To evaluate this, rats were divided into four groups as sham operated, ß-glucan treated sham operated, CLP, and ß-glucan treated CLP. Sixteen hours after operation, rats were decapitated and zinc (Zn) and copper (Cu) levels were determined in the liver, kidney, heart, diaphragm, and lung tissues. The results demonstrate that sepsis significantly decreased zinc and copper levels of all tissues. The decrease in tissue zinc and copper levels demonstrates the role of trace elements in sepsis-induced tissue damage. Our results indicated that ß-glucan administration did not return the zinc and copper levels to the control group level, and it seems likely that the given dose of ß-glucan was insufficient to prevent sepsis-induced organ injury.

Effects of a Glucan from the Edible Mushroom (Pleurotus florida) as an Immunostimulant in Farmed Indian Major Carp (Catla catla)

The purpose of this study was to determine the effects of a dietary mushroom glucan on the non- specific immune responses and disease resistance of the Indian major carp, Catla catla. Glucan was extracted from farm-raised edible mushrooms (Pleurotus florida). The glucan was fed to test animals for two weeks at 0.5 g or 1 g/kg feed. Afterward, the fish received the control diet for another four weeks. Non-specific immune responses were measured at the end of the two-week experimental feeding (week 0), two weeks later (week 2), and four weeks later (week 4). Control and test fish were challenged by intraperitoneal injection of the fish pathogenic bacterium, Aeromonas hydrophila, seven days after the two-week experimental feeding period. Mortality was observed and the relative percent survival was calculated. In the 0.5 g treatment, significant enhancement (p<0.05) in superoxide anion production was observed at weeks 0 and 2. In the 1 g treatment, activity was enhanced only at week 2. Both concentrations significantly increased phagocytosis at weeks 0 and 2 and bactericidal activity at weeks 2 and 4 (p<0.05). Alternative complement pathway activity was unaltered by either treatment (p>0.05), but lysozyme activity was raised at weeks 2 and 4 in the 0.5 g treatment and at week 2 in the 1 g treatment. Both con- centrations significantly enhanced relative percent survival.

Potentiation of Histamine Release by Microfungal (1→3)‐ and (1→6)‐β‐D‐Glucans

(1-->3)-beta-D-Glucans, a cell wall component in most microfungi, are suggested to play a role in the development of respiratory and general symptoms in organic dust-related diseases. The mechanisms by which they induce these effects are, however, not clear. In the present study, mediator release and its potentiation by the (1-->3)-beta-D-glucan as well as by the (1-->6)-beta-D-glucan found in yeast and other fungi were therefore examined. Blood leucocytes from healthy volunteers and from patients allergic to house dust mite were incubated with (1-->3)-beta-D-glucans with increasing 1,6-branchings: curdlan [a linear (1-->3)-beta-D-glucan], laminarin and scleroglucan, and furthermore with pustulan, a linear (1-->6)-beta-D-glucan. Histamine release was not observed on exposure to the glucans only, but in the presence of anti-immunoglobulin E (IgE) antibody or specific antigens, all the glucans investigated led to an enhancement of the IgE-mediated histamine release. The glucans induced a significant potentiation of the mediator release when present at concentrations in the range of 2-5 x 10(-5) M. These results suggest that (1-->3)-beta-D-glucan as well as (1-->6)-beta-D-glucan aggravates IgE-mediated histamine release. Knowledge concerning the effects of glucans on immune responses may be of importance for understanding and treating inflammatory and allergic diseases.

Glucan and Glutamine Reduce Bacterial Translocation in Rats Subjected to Intestinal Ischemia–Reperfusion

Intestinal ischemia/reperfusion (I/R) may induce bacterial translocation (BT). Glutamine (GLN)-enriched nutrition decreases BT. However, little is known about the effect of glucan (GL) in BT. This study investigated the combined effect of GL/GLN on BT, intestinal damage, and portal blood cytokines in animals under I/R. Four groups of 10 rats each were subjected to 60 min of intestinal ischemia and 120 min of reperfusion. The control group (group 1) received only rat food/water, group 2 received glutamine via gavage, group 3 received subcutaneuos soluble (1, 3)-d-glucan, and group 4 received GL + GLN. A sham group (group 5) served as a normal control. Bacterial cultures of ileum, mesenteric lymph nodes (MLN), liver and lung biopsies, histological changes of ileum, and serum cytokines variables were examined after I/R. Data were analyzed by analysis of variance (ANOVA) and the Newman–Keuls test. Results showed that GLN, GL, and GL/GLN significantly reduced BT to MLN, liver, and lung. BT was more attenuated after GL treatment than GLN (P <. 05). Rats treated with both GL and GLN exhibited lower bacterial colony counts than the ones treated only with GLN or GL. Severe mucosal damage on histological findings was shown in group 1, but these findings were significantly ameliorated (P <. 05) in groups 3 and 4. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels in portal serum were significantly reduced and IL-10 was increased by GL and GLN treatment. In conclusion, the use of GL was more effective than GLN in reducing BT, intestinal damage, and cytokine levels after I/R. Additionally, the combination of GL and GLN improved results.

Short-Term Satiety and Glycemic Response After Consumption of Whole Grains with Various Amounts of beta-Glucan

The effects of a meal with and without soluble dietary fiber in the form of beta-glucan on short-term satiety and glucose response were investigated in 19 overweight subjects. Subjects consumed four isocaloric test meals consisting of a glucose solution or wheat (0 g of beta-glucan), a wheat-barley mixture (1 of beta-glucan), or barley (2 of P-glucan) served as cooked cereal with low-fat strawberry yogurt. Subjects used visual analog scales (VAS) to rate their hunger, fullness, satisfaction, thirst, nausea, and drowsiness at timed intervals before and after consumption of each test meal. Blood glucose was measured periodically, and energy intake was recorded 2 hr after consumption of each test meal. In women peak glucose responses and area under the curve were significantly lower after consumption of 2 of beta-glucan compared with consumption of 0 or 1 g of beta-glucan. VAS ratings did not significantly differ among cereals. In men no effect of glucan on glucose response was observed, and beta-glucan had only a marginal effect oil VAS ratings. Energy intake was not affected by beta-glucan level in either women or men. The findings indicate that acute reduction of glycemic response in overweight women requires the comsumption of at least 2 g of beta-glucan per meal, and greater amounts of beta-glucan per meal may be required to achieve substantial satiety effects in overweight women and men.

Immunomodulatory effects of β-glucan on neutrophil function in fathead minnows ( Pimephales promelas Rafinesque, 1820)

Stimulatory effects of yeast β-1,3–1,6-glucans on neutrophils have long been recognized, but effects of glucans on degranulation of primary granules in fish neutrophils have not been previously reported. Neutrophil function was monitored during in vitro and in vivo application of glucans to non- (NS), acute- (AS) and chronically stressed (CS) fish. β-Glucan proved to be a strong and quick (80%, 2 min) stimulant of degranulation. Dietary glucan increased degranulation in NS fish, and prevented a decrease in AS fish. Degranulation in CS fish returned to NS levels 3 days after the glucan diet was fed. Fathead minnows appear to be a useful model to investigate neutrophil degranulation in fish exposed to different environmental conditions and immunomodulators. Use of β-glucans in fish diets prior to AS and during chronic stress can enhance neutrophil function, potentially increasing disease resistance and survival rates after transportation or exposure to poor water quality.

Effect of glucans from different races of Phytophthora infestans on defense reactions in potato tuber

It has been proposed that susceptibility of potato to Phytophthora infestanswould be a consequence of suppression and /or delaying of defense reactions by a soluble glucan which is released by compatible races of the fungus. In this report, the reaction of potato tuber slices ( Solanum tuberosum cv. Huinkul) infected with either race I (1,4,7,8,10,11) or C (1,4,10,11) of Phytophthora infestans was studied. Race C grew better on slices than race I. Glucans from both races were isolated and their effect on the accumulation of phytoalexins and glucanases in tuber slices was studied. The glucans from the less virulent race (I) did not affect the accumulation of phytoalexins and glucanases in tuber slices infected or elicited with eicosapentaenoic acid, whereas the glucans from race C produced 70% inhibition of phytoalexin accumulation and reduced by 50% the induction of glucanase activities. Purified glucanases from potato degraded the glucans from race C but not from race I. The results reported here show that, at least on this cultivar, glucans from both races affected defense responses in a different manner, which could reflect structural differences between these glucans. Abbreviations:EPA ‐ 5,8,11,14,17 eicosapentaenoic acid.

Effect of glucan on murine lupus evolution and on host resistance toKlebsiella pneumoniae

Glucan is a polysaccharide from the yeast Saccharomyces cerevisiae that stimulates the mononuclear phagocytic system (MPS). NZB/NZW F1 mice were divided into two groups: one group received a subcutaneous injection of 0.5 mg glucan/animal for 1 week, and the other received the same dose for 3 months. No changes were observed in those animals submitted to short-term glucan treatment, whereas animals with active lupus and submitted to long-term glucan administration presented early death, with significant differences in accumulated mortality rates over 33-37 weeks, when compared to controls. No deaths were observed in lupus mice treated with glucan 24 hours before the induction of septic shock by Klebsiella pneumoniae, in contrast to mortality of 95.3% in the control group during the follow-up period of 12 days. We conclude that although glucan is able to exacerbate lupus activity, it enhances resistance to infection in lupus mice.

Effect of glucan on murine lupus evolution and on host resistance to Klebsiella pneumoniae

Effect of glucan on murine lupus evolution and on host resistance to Klebsiella pneumoniae