Effects of short-term fructooligosaccharide intake on equol production in Japanese postmenopausal women consuming soy isoflavone supplements: a pilot study

BACKGROUND

Recent studies suggest that some of the clinical effectiveness of soy or daidzein, which is a type of isoflavone, may be attributed to a person's ability to produce equol from daidzein. Equol, which is a metabolite of one of the major soybean isoflavones called daidzein, is produced in the gastrointestinal tract by certain intestinal microbiota where present. Habitual dietary patterns may alter the intestinal bacterial profile, and influence the metabolism of isoflavones and the production of equol. Fructooligosaccharides (FOS) have a prebiotic activity as well as being a dietary fibre. The purpose of the present study was to determine whether FOS supplementation increases equol production in equol producers and stimulates equol production in equol non-producers in Japanese postmenopausal women.

METHODS

A soy challenge was used to assess equol-producer status prior to the start of the study in healthy postmenopausal Japanese women. The study involved 4 separate groups in randomised crossover design. First, subjects were classified as equol producers (n = 25) or non-producers (n = 18), and then they were randomly assigned to the FOS or control group. All subjects received a daily dose of 37 mg isoflavone conjugates in the capsule (21 mg aglycone form) and either FOS (5 g/day) or sucrose as control, in a randomised crossover study design. Equol -production was assessed by testing the serum and urine before and after the 2-week supplementation period.

RESULTS

The analyses were conducted on 34 subjects completed the study, 21 (61.8%) were classified as equol producers, and 13 (38.2%) as non-producers. Significant differences were observed in the interaction effect of time × equol state after 1 week of intervention (p = 0.006). However there were no effects after 2 weeks of intervention (p = 0.516). Finally, in both equol producers and non-producers, FOS supplementation did not affect the serum equol concentration or the urinary equol to daidzein concentration ratios.

CONCLUSIONS

We have reported that FOS intervention (5 g/day for 2 weeks) does not significantly modulate the capacity of intestinal microbiota to produce equol in postmenopausal Japanese women, in either equol producers or non-producers in this pilot study. Further larger investigations that explore the roles of specific intestinal microbiota in equol production will enable the establishment of dietary conditions that are required to enhance equol production.

β-glucan enriched bath directly stimulates the wound healing process in common carp (Cyprinus carpio L.)

Wound healing is a complex and well-organized process in which physiological factors and immune mechanisms are involved. A number of different immune modulators have been found to enhance the non-specific defence system in vertebrates, among which β-glucans are the most powerful and extensively investigated. The aim of the present study was to investigate the biological impact of two different commercially available β glucan containing products on the wound healing process in carp. Throughout a two week experiment fish were kept either untreated (control), or in water supplemented with the two different types of β-glucans. The wound healing process was monitored using a multispectral visualisation system. The correlation between wound closure and immune response was investigated by measuring the gene expression patterns of IL-1β, IL-6 family member M17, IL-8 and Muc5b, and measurement of production of radical oxygen species. PAMPs/DAMPs stimulation caused by the wounding and or β-glucans resulted in an inflammatory response by activating IL-1β, IL-6 family member M17 and IL-8 and differences in the expression pattern were seen depending on stimuli. IL-1β, IL-6 family member M17 and IL-8 were activated in all wounds regardless of treatment. Expression of all three interleukins was highly up regulated in control wounded muscle already at day 1 post-wounding and decreased at subsequent time-points. The reverse was the case with control wounded skin, where expression increased from day 1 through day 14. The results for the β-glucan treated wounds were more complex. The images showed significantly faster wound contraction in both treated groups compared to the control. The obtained results clearly demonstrated that a β glucan enriched bath promotes the closure of wounds in common carp and induce a local change in cytokine expression.

Immunostimulatory properties and antitumor activities of glucans (Review)

New foods and natural biological modulators have recently become of scientific interest in the investigation of the value of traditional medical therapeutics. Glucans have an important part in this renewed interest. These fungal wall components are claimed to be useful for various medical purposes and they are obtained from medicinal mushrooms commonly used in traditional Oriental medicine. The immunotherapeutic properties of fungi extracts have been reported, including the enhancement of anticancer immunity responses. These properties are principally related to the stimulation of cells of the innate immune system. The discovery of specific receptors for glucans on dendritic cells (dectin-1), as well as interactions with other receptors, mainly expressed by innate immune cells (e.g., Toll-like receptors, complement receptor-3), have raised new attention toward these products as suitable therapeutic agents. We briefly review the characteristics of the glucans from mycelial walls as modulators of the immunity and their possible use as antitumor treatments.

Successful therapy of visceral leishmaniasis with curdlan involves T-helper 17 cytokines

The aim of this study was to evaluate and characterize the therapeutic potential of curdlan, a naturally occurring β-glucan immunomodulator, against visceral leishmaniasis, a fatal parasitic disease. Curdlan eliminated the liver and spleen parasite burden in a 45-day BALB/c mouse model of visceral leishmaniasis at a dosage of 10 mg/kg/day as determined by Giemsa-stained organ impression smears. Curdlan was associated with production of the disease-resolving T-helper (Th) 1 and Th17-inducing cytokines interleukin (IL)-6, IL-1β, and IL-23, as well as with production of Th17 cytokines IL-17 and IL-22, as determined by enzyme-linked immunosorbent assay (ELISA) and real time polymerase chain reaction (RT-PCR). Reversal of curdlan-mediated protection by anti-IL-17 and anti-IL-23 monoclonal antibodies showed the importance of Th17 cytokines. Significantly decreased production of both IL-17 and IL-22 by mice that received anti-IL-23 antibody suggested the essential role of IL-23 in Th17 differentiation. Although administration of recombinant IL-17 or IL-23 caused significant suppression of the organ parasite burden, with marked generation of interferon γ and nitric oxide (NO), effects were much faster for IL-17. These results documented that although both IL-23 and IL-17 play major roles in the antileishmanial effect of curdlan, the effect of IL-23 may occur indirectly, through the induction of IL-17 production.

Oat prevents obesity and abdominal fat distribution, and improves liver function in humans

Obesity is associated with a great diversity of diseases including non-alcoholic fatty liver disease. Our recent report suggested that oat, rich in beta-glucan, had a metabolic-regulating and liver-protecting effect in an animal model. In this study, we performed a clinical trial to further confirm the effect of oat. Subjects with BMI ≥27 and aged 18-65, were randomly divided into a control (n=18) and an oat-treated (n=16) group, taking a placebo or beta glucan-containing oat cereal, respectively, for 12 weeks. Our data showed that consumption of oat reduced body weight, BMI, body fat and the waist-to-hip ratio. Profiles of hepatic function, including AST, but especially ALT, were useful resources to help in the evaluation of the liver, since both showed decrements in patients with oat consumption. Nevertheless, anatomic changes were still not observed by ultrasonic image analysis. Ingestion of oat was well tolerated and there was no adverse effect during the trial. In conclusion, consumption of oat reduced obesity, abdominal fat, and improved lipid profiles and liver functions. Taken as a daily supplement, oat could act as an adjuvant therapy for metabolic disorders.

Safety and efficacy of polycalcium for improving biomarkers of bone metabolism: a 4-week open-label clinical study

Polycalcium is a mixture of Polycan and calcium lactate-gluconate 1:9 (w/w) with demonstrated antiosteoporosis activity in vitro and in vivo studies. These studies were a 4-week open-label, single-center trial to evaluate the efficacy of oral Polycalcium on bone metabolism and safety. In total, 30 healthy women (range 40-60 years) were administered 400 mg of Polycalcium for 4 weeks. The primary efficacy parameter was urinary deoxypyridinoline (DPYR) levels, and serum osteocalcin (OSC), bone-specific alkaline phosphatase (BALP), urinary cross-linked C-telopeptide of type-1 collagen (CTx), urinary cross-linked N-telopeptide of type-1 collagen (NTx), calcium (Ca), and phosphorus (P) levels, which were evaluated for comparison before and after administration of Polycalcium. After 4 weeks of Polycalcium administration, 27 subjects completed the test plan. Three subjects withdrew their consent to participate. The values of blood OSC, BALP, serum Ca, and serum P from baseline to 4 weeks of treatment were changed by -28.44%, 14.37%, 6.11%, and 1.42%, respectively. Biomarkers of bone resorption: urinary DPYR, serum CTx, serum NTx, urinary Ca, and urinary P, at baseline after 4 weeks of treatment were changed by -13.40%, 6.67%, -5.13%, -22.43%, and -3.04%, respectively. Additionally, when considering the subjects' adverse effects and the results of the blood and urine tests over the 4-week trial period, the dose of 400  mg Polycalcium showed efficacy for improving bone metabolism and was well tolerated and safe. Polycalcium was apparently safe and efficacious.

Pleuran (β-glucan from Pleurotus ostreatus ): an effective nutritional supplement against upper 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.

Up-regulation of GITRL on dendritic cells by WGP improves anti-tumor immunity in murine Lewis lung carcinoma

BACKGROUND

β-Glucans have been shown to function as a potent immunomodulator to stimulate innate and adaptive immune responses, which contributes to their anti-tumor property. However, their mechanisms of action are still elusive. Glucocorticoid-induced TNF receptor ligand (GITRL), a member of the TNF superfamily, binds to its receptor, GITR, on both effector and regulatory T cells, generates a positive co-stimulatory signal implicated in a wide range of T cell functions, which is important for the development of immune responses.

METHODOLOGY/PRINCIPAL FINDINGS

In this study, we found that whole β-glucan particles (WGPs) could activate dendritic cells (DCs) via dectin-1 receptor, and increase the expression of GITRL on DCs in vitro and in vivo. Furthermore, we demonstrated that the increased GITRL on DCs could impair the regulartory T cell (Treg)-mediated suppression and enhance effector T cell proliferation in a GITR/GITRL dependent way. In tumor models, DCs with high levels of GITRL were of great potential to prime cytotoxic T lymphocyte (CTL) responses and down-regulate the suppressive activity of Treg cells, thereby leading to the delayed tumor progression.

CONCLUSIONS/SIGNIFICANCE

These findings suggest that particulate β-glucans can be used as an immunomodulator to stimulate potent T cell-mediated adaptive immunity while down-regulate suppressive immune activity via GITR/GITRL interaction, leading to a more efficient defense mechanism against tumor development.

[Investigation of combined effectiveness of spiramycin and beta-glucan in mice models of acute toxoplasmosis and determination of IL-10, IL-12 and TNF-α levels]

Toxoplasmosis which is caused by Toxoplasma gondii, has a high risk of fetal infection development if the infection occurs during pregnancy. Treatment with oral spiramycin is recommended during pregnancy in order to prevent the transmission of protozoa to fetus and development of infection. Since beta- glucan is known to stimulate the immune system and increase the phagocytic activity of the cells, it has been shown to exhibit immunomodulatory effect on many infectious diseases. The objectives of this study were to investigate the effectiveness of beta-glucan alone and in combination with spiramycin and to determinate the levels of interlökin (IL)-10, IL-12 and tumor nekrosis factor (TNF)-α in mice experimentally infected with T.gondii. For this purpose, four experimental groups each consisting of eight BALB/c mice, were formed with the approval of Ethics Committee for the Animal Experiments. All the mice were infected with 2 ml of suspension containing 2 x 102/ml of trophozoite prepared from T.gondii RH strain (Refik Saydam National Public Health Agency, Parasitology Laboratory of Communicable Diseases Research Department, Ankara, Turkey), by intraperitoneal injection. Twenty-four hours after the infection, beta-glucan (3 mg/day) was given to the beta-glucan group, spiramycin (200 mg/kg/day) to the spiramycin group, beta-glucan (3 mg/day) plus spiramycin (200 mg/kg/day) to the beta-glucan-spiramycin (BG-S) group by oral gavage. The fourth group which was the control group was infected but untreated. The above administration was carried out for seven days. On the 8th day, under anaesthesia, 1 ml normal saline was given into the peritoneum, drawn back later and the number of trophozoites in 1 ml of peritoneal fluid was determined by counting them on the Thoma slide. Moreover, by drawing the heart blood; IL-10, IL-12, TNF-α levels were determined in serum samples by ELISA method (eBioscience Platinum, Austria). The number of trophozoites in the BG-S group was found significantly lower than the number of trophozoites in control, beta-glucan and spiramycin groups (p< 0.05). There was no significant difference between the beta-glucan and spiramycin groups, however the number of trophozoites in both groups was significantly lower than the number of trophozoites in the control group (p< 0.05). There was a certain decrease in IL-10 level in spiramycin and BG-S groups, compared to the control group, in addition when IL-10 levels in spiramycin and BG-S groups were compared with BG group, a significant decrease was noticed (p< 0.05). There was no difference in IL-12 levels between the groups, while there was a certain decrease in TNF-α level in beta-glucan, spiramycin, BG-S group in comparison to the control group. Within the reach of our literature survey, this study is the first research in which the effectiveness of the combination of beta-glucan and spiramycin in the treatment of acute toxoplasmosis was investigated. The results of our study suggested that there might be synergy between beta-glucan and spiramycin in the treatment of acute toxoplasmosis.

Interaction of barley β-glucan and tea polyphenols on glucose metabolism in streptozotocin-induced diabetic rats

Soluble dietary fiber and antioxidants have received much attention as most important components of functional foods. However, few data are available on the effects of the combination of tea polyphenols (TP) and β-glucan (BG) on blood glucose in a diabetic rat. The effects of administration of barley BG and TP or their combination (TP + BG) on blood glucose, lipid profiles, and antioxidant parameters on streptozotocin-induced diabetic rats were investigated. Significant improvements on the blood glucose level, serum lipid parameters (decreases in triglyceride, total cholesterol, LDL-C, and increase in HDL-C), lipid peroxidation (decrease in malondiadehyde content), and serum antioxidant status (increases in superoxide dismutase, glutathione peroxidase, and total antioxidant capacity) resulted in diabetic rats after administering TP + BG. This study, therefore, demonstrated that the intake of TP + BG has beneficial effects on glucose tolerance, lipid metabolism, and serum antioxidant status. It also revealed that TP + BG is better than TP or BG alone in improving glucose metabolism and antioxidant status in diabetic rats. Practically, the present study suggested that polyphenols-rich cereal foods are help for type 2 diabetes.

PRACTICAL APPLICATION

Although TP or BG was definitely helpful in the treatment and management of diabetes mellitus, synthetic anti-hyperglycemic effects were found between TP and BG. The fortification of a BG-rich cereal diet with TP could be used as a strategy to maintain health of diabetic subjects.

[Bacterial vaginosis. Treatment of the relapse]

Bacterial vaginosis (BV) is a common vaginal infection in women of reproductive age. Bacterial vaginosis is an ecological disorder that ensues when normal lactobacilli are replaced by large numbers of Gardnerella vaginalis, Prevotella sp., Bacteroides sp., Mobiluncus sp. and M. hominis. Numerous studies have consistently shown that BV at 12-24 weeks are associated with increased risks of preterm birth (PTB), preterm rupture of the membranes, chorioamnionitis, fetal infection and cerebral palsy. Deficiencies in local immunity may predispose women to BV.

Combination of glucan, resveratrol and vitamin C demonstrates strong anti-tumor potential

β-Glucans are naturally occurring carbohydrates found in plants, fungi and some bacterial species, and currently are well-established and powerful immunomodulators with beneficial properties in cancer therapy. Recent studies suggested that some additional bioactive molecules have synergistic effects when combined with glucan. In the current study, we evaluated the anticancer properties of glucan, resveratrol, vitamin C combination. We found that compared to the individual components, the combination was the strongest activator of phagocytosis and antibody formation. Using two different models of cancer treatment, our results demonstrated that the combination strongly suppressed the growth of breast and lung tumors, most likely due to the stimulation of apoptosis.

Efficacy of a new medical device based on colloidal silver and carbossimetyl beta glucan in treatment of upper airways disease in children

AIM

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.

METHODS

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).

RESULTS

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.

CONCLUSION

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.

Effect of beta-glucan, inositol and digestive enzymes in GI symptoms of patients with IBS

BACKGROUND

Irritable bowel syndrome (IBS) is a very common functional gastrointestinal (GI). Diagnosis of IBS is based on the fulfilment of the Rome III criteria. Common GI symptoms are lower abdominal pain, bloating and disturbed defecation, such as urgent diarrhoea and/or episodes of chronic constipation. Many agents have been employed in the management of IBS, although only few have been demonstrated to show a relevant efficacy.

AIM

To evaluate the effectiveness of the administration of a mixture of beta-glucan, inositol and digestive enzymes (Biointo) in improving GI symptoms in patients affected by IBS.

PATIENTS AND METHODS

50 IBS patients (20 males, 30 females; mean age 51 +/- 19) were treated with Biointo (group A) while another group consisting of 40 IBS patients (15 males, 25 females; mean age 50 +/- 18) did not receive any therapy (group B).

RESULTS

Biointol administration improved significantly bloating, flatulence and abdominal pain, with a slight increasing of urgency for bowel movements. On the contrary, Biointol did not show any significant effect on the other IBS symptoms.

CONCLUSIONS

Currently, only few agents used in the management of IBS have been proven to be effective. Biointol administration has shown to improve some IBS symptoms, such as bloating, flatulence and abdominal pain, all connected to the presence of gas inside the intestinal lumen.

Immune modulating effects of β-glucan

PURPOSE OF REVIEW

To examine the recent scientific literature on the immune modulating effects of β-glucans and subsequent benefits on infection and cancer.

RECENT FINDINGS

β-Glucans have been investigated for their ability to protect against infection and cancer and more recently for their therapeutic potential when combined with cancer therapy. Their immune modulating effects are attributed to the ability to bind to pattern recognition receptors including complement receptor 3, scavenger receptors, lactosylceramide, and dectin-1 that results in activation of different aspects of the immune response depending on the cell types and species involved although there is some controversy about the relative importance of each of these receptors. Most of the available evidence comes from preclinical data and human studies are just now beginning to appear in the literature, therefore firm conclusions on its clinical importance cannot yet be made. Perhaps the most promising evidence to date in human trials has come from recent studies on a benefit of β-glucan on quality of life and survival when given in combination with cancer treatment. We identify the need for future studies that compare purified forms of β-glucans from different sources to further the understanding of the mechanisms of action and aid in the development of clinical studies.

SUMMARY

β-Glucans appear to be effective at enhancing immune function and reducing susceptibility to infection and cancer. A better understanding of the mechanisms of β-glucan recognition and subsequent immune activation is necessary for the design of effective treatment approaches in future clinical trials.

[Effectiveness of the treatment with beta-glucan in the HPV-CIN 1 lesions]

AIM

The aim of the study was to evaluate the effectiveness of the beta-glucan in women with abnormal cytology, including the women with a positive screening for ASCUS-LSIL furtherly divided in women with positive cytology (ASCUS or LSIL) and negative colposcopy and women with abnormal cytology, positive colposcopy and human papilloma virus (HPV)-CIN1 hystology who opted for follow-up.

METHODS

From September 2007 to December 2008, 60 women with ASCUS-LSIL diagnosis were recruited at the ambulatory of Lasersurgery and Cervico-Vaginal Patology, Department of Gynecology and Obstetrics of Policlinico Umberto I of Rome. The women was subdivided in two groups: 1) women with cytological diagnosis of ASCUS or LSIL and negative colposcopy; 2) women with abnormal cytology, positive colposcopy and HPV-CIN1 histology, who opted for follow-up. All the women were treated with two cycles of a daily topical application of beta-glucan for 20 consecutive days with a suspension of 10 days. The effects of beta-glucan were analyzed with colposcopy and cytology at 3.6 and 12 months from the beginning of the therapy.

RESULTS

After 3 months of treatment, of the 30 women with positive cytology and negative colposcopy, 80% with ASCUS diagnosis resulted negative, 35% with LSIL diagnosis resulted negative; after 6 months 100% with ASCUS diagnosis resulted negative, 70% with LSIL diagnosis resulted negative; after 12 months 85% with LSIL diagnosis resulted negative. Of the 30 women with positive cytology, positive colposcopy and HPV-CIN1 histology after 3 months 20% resulted negative, after 6 months 60% resulted negative and after 12 months 80% resulted negative. The persistence of the HPV-CIN1 histology was verified in the 13% of the women. For these women the definitive treatment was the TFD.

CONCLUSION

Our study demonstrate the effectiveness of the treatment with beta-glucan in the women with ASCUS-LSIL lesions and HPV-CIN1 lesions, increasing of the regressions rate after 12 months of the treatment of the 15-20%.

[Role of beta-glucan in the treatment of recurrent candidiasis and HPV-correlated lesions and reparative process of epidermis]

AIM

The aim of the study was to examine the effects of beta-glucan treatment in women with recurrent vulvar candidiasis or previously treated with diathermocoagulation (DTC) for vulvar lesions caused by human papillomavirus (HPV) infection.

METHODS

From January to March 2008, 23 women with a history of recurrent candidiasis and 209 women who underwent to DTC for HPV-correlated vulvar lesions were recruited at the Department of Obstetrics and Gynaeco-logy of San Camillo-Forlanini Hospital of Rome. The two groups were treated with two cycles of a daily topical application of beta-glucan for 15 consecutive days with a suspension of 20 days. The effects of beta-glucan were analyzed at the 1st and the 3rd month from the start of the therapy.

RESULTS

A total of 209 women, 21 with recurrent candidiasis and 188 who underwent to DTC for HPV-correlated lesions, completed the study. After the first month of treatment we not found any evidence of disease in both groups; otherwise we observed, a month after the term of the therapy, 5% and 3% of recurrence of candidiasis or lesions secondary to HPV infection, respectively, even if with low grade.

CONCLUSIONS

Our results demonstrate the efficacy of beta-glucan treatment for recurrent candidiasis, HPV-correlated lesions and in the reparative process of epidermis.

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.

Cardioprotective effect of pretreatment with β-glucan in coronary artery bypass grafting

BACKGROUND

Beta-glucan pretreatment has been shown to attenuate inflammatory response and to protect against ischemia-reperfusion injury in animal studies. The aims of the present study were to examine the safety of pretreatment with beta-1,3/1,6-glucan in patients scheduled for coronary artery bypass grafting (CABG), and to investigate whether beta-1,3/1,6-glucan pretreatment could suppress inflammatory response and protect against ischemia-reperfusion injury following CABG.

METHODS

Twenty one patients scheduled for CABG were assigned to oral beta-1,3/1,6-glucan 700 mg (Group 1) or 1 400 mg (Group 2) five consecutive days before surgery and were compared with a control group (Group 3). Blood samples were drawn preoperatively and on the first, third and fifth postoperative day for analysis of acute-phase reactants, hematology, cytokines and myocardial enzymes.

RESULTS

The study drug was well tolerated. Creatine kinase isoenzyme MB was significantly lower in Group 2 compared with controls on the first postoperative day (p = 0.028). Mean change in cardiac troponin T was lower in Group 2 compared with controls (p = 0.028).

CONCLUSIONS

Beta-1,3/1,6-glucan pretreatment is safe in patients undergoing CABG and may protect against ischemia reperfusion injury following CABG.

The efficacy of two immunostimulants against Flavobacterium columnare infection in juvenile rainbow trout (Oncorhynchus mykiss)

Bacterium Flavobacterium columnare is the causative agent of columnaris disease in many wild and farmed fish species. Immunostimulants are used with success in aquaculture against many pathogens, but the ability to improve innate resistance to columnaris disease has not been studied. Fingerling rainbow trout were treated with two immunostimulants, yeast beta-glucan and beta-hydroxy-beta-methylbutyrate (HMB). Selected innate immune function parameters, the production of reactive oxygen species (ROS) by whole blood and by isolated head kidney leukocytes, plasma lysozyme activity and complement bacteriolytic activity, were determined to assess the immune status of fish. The fish were then bath challenged with virulent F. columnare bacteria, and the mortality of fish was recorded. Given orally both stimulants raised the levels of immune function parameters, but did not improve survival in challenge at any concentration of the stimulants used. Intra peritoneal injection of beta-glucan increased parameter values several fold, but no beneficial effect of injected glucan on survival was noted. As a control, antibiotic medication administered prior to and during the challenge infection prevented the mortality. Innate immune mechanisms, even when induced to high levels with immunostimulants, as evidenced here, were not able to increase resistance against F. columnare. This may be connected to the external character of the infection. The results from the treatments with beta-glucan and HMB suggest that there is little prospect of preventing columnaris disease by means of immunostimulants in early life stage of rainbow trout. However, the efficacy of other immune stimulants remains open.

[The biological activity of beta-glucans]

This review summarizes the recent knowledge about the positive effect of betaglucans on human health. Beta-glucans are polysaccharides occurring in the bran of cereal grains (barley and oats and to a much lesser degree in rye and wheat, in amounts of about 7%, 5%, 2% and less than 1%, respectively), the cell wall of baker's yeast, certain types of fungi, and many kinds of mushrooms. The differences between soluble and insoluble beta-glucans are significant in regards to application, mode of action, and overall biological activity. A growing body of science indicates that beta-glucans promote health in a number of important ways. Beta-glucans have been studied for their hypocholesterolemic effects; these mechanisms include: reducing the intestinal absorption of cholesterol and bile acids by binding to glucans; shifting the liver from cholesterol syntheses to bile acid production; and fermentation by intestinal bacteria to short-chain fatty acids, which are absorbed and inhibit hepatic cholesterol syntheses. Several studies have also shown that oat beta-glucans blunt the glycemic and insulin response. Moreover, beta-1,3-glucans improve the body's immune system defense against foreign invaders by enhancing the ability of macrophages, neutrophils and natural killer cells to respond to and fight a wide range of challenges such as bacteria, viruses, fungi, and parasites. Finally, there is renewed interest in the potential usefulness of beta-glucan as a radioprotective drug for chemotherapy, radiation therapy and nuclear emergencies, particularly because glucan can be used not only as a treatment, but also as a prophylactic.

Treatment of Lewis lung carcinoma by photodynamic therapy and glucan from barley

OBJECTIVE

During the photodynamic treatment, complement system is activated and tumor cells are opsonized with iC3b fragment. beta-glucans can enhance cytotoxicity of iC3b-opsonized cells due to their specific interaction with complement receptor 3 (CR3; CD11b/CD18) on the surface of the effector cells. In contrast to microorganisms, tumor cells lack beta-glucan as a surface component and cannot trigger complement receptor 3-dependent cellular cytotoxicity and initiate tumor-killing activity. This mechanism could be induced in the presence of beta-glucans. This study aimed at determining the influence of coadministration of beta-glucan from barley on the efficacy of photodynamic tumor therapy (PDT).

MATERIAL AND METHODS

C57 Bl/6 female mice bearing Lewis lung carcinoma were used throughout the study. Mice were randomized into groups (15 in each group) and exposed to the treatment with intravenous Photofrin injection (dose, 10 mg/kg) and after 24 h following laser illumination, or with oral administration of beta-glucan from barley at a dose of 400 microg/mouse per day up to 5 days, or with their combination. Tumor growth dynamics and survival of the treated and untreated mice were monitored.

RESULTS

Tumor volume in all treated groups was significantly lower (P<0.001) than that in the control group. The most effective tumor growth suppression (P=0.033) was achieved in mice treated with combination of PDT and beta-glucan from barley as compared with PDT alone. The best survival was achieved in the same group, but difference was not significant as compared to the control group (P=0.143) and to PDT alone group (P=0.319).

CONCLUSIONS

The present study demonstrates that coadministration of beta-glucan from barley can enhance efficacy of photodynamic therapy.

[Action of β-glucan in pigs experimentally infected with Toxoplasma gondii tachyzoites]

The present study tested the action of Beta-glucan in swine experimentally infected with tachyzoites of Toxoplasma gondii. The experiment design used 8 mixed breed pigs (21 days) divided into three groups: G1 (Beta-glucan treated and infected, n = 3), G2 (untreated and infected, n = 3), and G3 (untreated uninfected, n = 2). The G1 animals were treated with 1g of Beta-glucan by intramuscularly route at days 0, 14, and 28 before experimental infection, while the other groups (G2 and G3) received only saline. The G1 and G2 were infected with viable tachyzoites (107) of the RH strain at day 35 of experiment. The parasitemy was determined by mouse bioassay and PCR from whole blood of each swine, obtained at days 3, 7, 14, 21, 31, 39, 47 e 69 post infections. The antibody levels of serum, aqueous and vitreous humor were measured by indirect immunofluorescence assay (IFA); a title >/= 64 was considered as positive. There were differences in the hematocrit, hemoglobin, plasmatic proteins, and eosinophils values between groups (P< 0.05). The swine of G1 and G2 serum converted 7 days post infection, and the highest title observed was 1024 in two pigs. Samples of aqueous and vitreous humor did not show antibodies against T. gondii. Parasite was detected of whole blood on days 3, 14, 31, 39, and 47 in two animals from G1, and three animals from G2. There were no differences between PCR and mouse bioassay. Animals from G3 remained without parasitemy by both PCR and bioassay throughout the experiment. The use of Beta-glucan, as was used here, was not protective for pigs against T. gondii tachyzoites acute infection. Additionally, the lineage of RH strain showed nonpersistent for pigs (muscles and retina) 69 days after infection.

Food labeling: health claims; soluble fiber from certain foods and risk of coronary heart disease. Final rule

The Food and Drug Administration (FDA) is adopting as a final rule, without change, the provisions of the interim final rule (IFR) that amended the regulation authorizing a health claim on soluble fiber from certain foods and risk of coronary heart disease (CHD), to add barley betafiber as an additional eligible source of beta-glucan soluble fiber. FDA is taking this action to complete the rulemaking initiated with the IFR.