Lactobacillus acidophilus NCFM and Lactiplantibacillus plantarum Lp-115 inhibit Helicobacter pylori colonization and gastric inflammation in a murine model.

Purpose: To determine the role of Lactobacillus strains and their combinations in inhibiting the colonization of H. pylori and gastric mucosa inflammation. Methods: Human gastric adenocarcinoma AGS cells were incubated with H. pylori and six probiotic strains (Lactobacillus acidophilus NCFM, L. acidophilus La-14, Lactiplantibacillus plantarum Lp-115, Lacticaseibacillus paracasei Lpc-37, Lacticaseibacillus rhamnosus Lr-32, and L. rhamnosus GG) and the adhesion ability of H. pylori in different combinations was evaluated by fluorescence microscopy and urease activity assay. Male C57BL/6 mice were randomly divided into five groups (uninfected, H. pylori, H. pylori+NCFM, H. pylori+Lp-115, and H. pylori+NCFM+Lp-115) and treated with two lactobacilli strains (NCFM and Lp-115) for six weeks. H. pylori colonization and tissue inflammation statuses were determined by rapid urease test, Hematoxylin-Eosin (HE) staining, immunohistochemistry, and qRT-PCR and ELISA. Results: L. acidophilus NCFM, L. acidophilus La-14, L. plantarum Lp-115, L. paracasei Lpc-37, L. rhamnosus Lr-32, and L. rhamnosus GG reduced H. pylori adhesion and inflammation caused by H. pylori infection in AGS cells and mice. Among all probiotics L. acidophilus NCFM and L. plantarum, Lp-115 showed significant effects on the H. pylori eradication and reduction of inflammation in-vitro and in-vivo. Compared with the H. pylori infection group, the mRNA and protein expression levels of IL-8 and TNF-α in the six Lactobacillus intervention groups were significantly reduced. The changes in the urease activity (ureA and ureB) for 1-7h in each group showed that L. acidophilus NCFM, L. acidophilus La-14, L. plantarum Lp-115, and L. rhamnosus GG effectively reduced the colonization of H. pylori. We observed a higher ratio of lymphocyte and plasma cell infiltration into the lamina propria of the gastric mucosa and neutrophil infiltration in H. pylori+NCFM+Lp-115 mice. The infiltration of inflammatory cells in lamina propria of the gastric mucosa was reduced in the H. pylori+NCFM+Lp-115 group. Additionally, the expression of IFN-γ was decreased significantly in the NCFM and Lp-115 treated C57BL/6 mice. Conclusions: L. acidophilus NCFM and L. plantarum Lp-115 can reduce the adhesion of H. pylori and inhibit the gastric inflammatory response caused by H. pylori infection.

Resistant starch supplementation increases crypt cell proliferative state in the rectal mucosa of older healthy participants.

There is strong evidence that foods containing dietary fibre protect against colorectal cancer, resulting at least in part from its anti-proliferative properties. This study aimed to investigate the effects of supplementation with two non-digestible carbohydrates, resistant starch (RS) and polydextrose (PD), on crypt cell proliferative state (CCPS) in the macroscopically normal rectal mucosa of healthy individuals. We also investigated relationships between expression of regulators of apoptosis and of the cell cycle on markers of CCPS. Seventy-five healthy participants were supplemented with RS and/or PD or placebo for 50 d in a 2 × 2 factorial design in a randomised, double-blind, placebo-controlled trial (the Dietary Intervention, Stem cells and Colorectal Cancer (DISC) Study). CCPS was assessed, and the expression of regulators of the cell cycle and of apoptosis was measured by quantitative PCR in rectal mucosal biopsies. SCFA concentrations were quantified in faecal samples collected pre- and post-intervention. Supplementation with RS increased the total number of mitotic cells within the crypt by 60 % (P = 0·001) compared with placebo. This effect was limited to older participants (aged ≥50 years). No other differences were observed for the treatments with PD or RS as compared with their respective controls. PD did not influence any of the measured variables. RS, however, increased cell proliferation in the crypts of the macroscopically-normal rectum of older adults. Our findings suggest that the effects of RS on CCPS are not only dose, type of RS and health status-specific but are also influenced by age.

Viral Infections, the Microbiome, and Probiotics.

Viral infections continue to cause considerable morbidity and mortality around the world. Recent rises in these infections are likely due to complex and multifactorial external drivers, including climate change, the increased mobility of people and goods and rapid demographic change to name but a few. In parallel with these external factors, we are gaining a better understanding of the internal factors associated with viral immunity. Increasingly the gastrointestinal (GI) microbiome has been shown to be a significant player in the host immune system, acting as a key regulator of immunity and host defense mechanisms. An increasing body of evidence indicates that disruption of the homeostasis between the GI microbiome and the host immune system can adversely impact viral immunity. This review aims to shed light on our understanding of how host-microbiota interactions shape the immune system, including early life factors, antibiotic exposure, immunosenescence, diet and inflammatory diseases. We also discuss the evidence base for how host commensal organisms and microbiome therapeutics can impact the prevention and/or treatment of viral infections, such as viral gastroenteritis, viral hepatitis, human immunodeficiency virus (HIV), human papilloma virus (HPV), viral upper respiratory tract infections (URTI), influenza and SARS CoV-2. The interplay between the gastrointestinal microbiome, invasive viruses and host physiology is complex and yet to be fully characterized, but increasingly the evidence shows that the microbiome can have an impact on viral disease outcomes. While the current evidence base is informative, further well designed human clinical trials will be needed to fully understand the array of immunological mechanisms underlying this intricate relationship.

Identification and Antibiotic Resistance Assessment of Ensifer adhaerens YX1, a Vitamin B12 -Producing Strain Used as a Food and Feed Additive.

This study provides phenotypic and molecular analyses of the antibiotic resistance of Ensifer adhaerens strain YX1 (CICC 11008s), a strain that was identified using a polyphasic taxonomy approach. The antibiotic resistance profile of E. adhaerens YX1 was assessed using the Clinical & Laboratory Standards Inst. (CLSI) method. The strain was susceptible to ciprofloxacin, levofloxacin, norfloxacin, ofloxacin, gentamicin, tobramycin, chloramphenicol, tetracycline, imipenem, and ceftazidime, and resistant to kanamycin, streptomycin, fosfomycin, and nitrofurantoin. The antibiotic resistance genes nsfA, nsfB, fosA, aph, and aadA1 were not detected in E. adhaerens YX1 via PCR using gene-specific primers. Subsequently, the genome sequence of E. adhaerens was screened for antibiotic genes. Although no antibiotic resistance genes were identified using the ResFinder database, five genes copies of one resistance gene, adeF, were detected using the Comprehensive Antibiotic Resistance Database (CARD). The results of this study will be useful for understanding the phenotypic and genotypic aspects of E. adhaerens antibiotic resistance. No safety issues were identified for E. adhaerens YX1 in terms of antibiotic resistance. Performing similar studies will be conducive to the safety assessment and control of the use of E. adhaerens in the food and feed industry. PRACTICAL APPLICATION: Few relevant reports are currently available regarding antibiotic resistance assessments or other safety evaluations for Ensifer adhaerens. Because of a lack of relevant information on the safety of this bacterium, including the genetic basis of antibiotic resistance in the production strain, it has not been recommended for use in the "qualified presumption of safety" (QPS) list and subsequent updated lists. The current study shows no safety issue of E. adhaerens YX1 in terms of its antibiotic resistance. These results are important as they provide an initial basis for an understanding of the antibiotic resistance/susceptibility of E. adhaerens YX1 (CICC 11008s), which produces vitamin B12 and is widely used in the food and feed industry.

Novel Genes and Metabolite Trends in Bifidobacterium longum subsp. infantis Bi-26 Metabolism of Human Milk Oligosaccharide 2'-fucosyllactose.

Human milk oligosaccharides (HMOs) function as prebiotics for beneficial bacteria in the developing gut, often dominated by Bifidobacterium spp. To understand the relationship between bifidobacteria utilizing HMOs and how the metabolites that are produced could affect the host, we analyzed the metabolism of HMO 2'-fucosyllactose (2'-FL) in Bifidobacterium longum subsp. infantis Bi-26. RNA-seq and metabolite analysis (NMR/GCMS) was performed on samples at early (A600 = 0.25), mid-log (0.5-0.7) and late-log phases (1.0-2.0) of growth. Transcriptomic analysis revealed many gene clusters including three novel ABC-type sugar transport clusters to be upregulated in Bi-26 involved in processing of 2'-FL along with metabolism of its monomers glucose, fucose and galactose. Metabolite data confirmed the production of formate, acetate, 1,2-propanediol, lactate and cleaving of fucose from 2'-FL. The formation of acetate, formate, and lactate showed how the cell uses metabolites during fermentation to produce higher levels of ATP (mid-log compared to other stages) or generate cofactors to balance redox. We concluded that 2'-FL metabolism is a complex process involving multiple gene clusters, that produce a more diverse metabolite profile compared to lactose. These results provide valuable insight on the mode-of-action of 2'-FL utilization by Bifidobacterium longum subsp. infantis Bi-26.

Intestinal microbiota is altered in patients with colon cancer and modified by probiotic intervention.

OBJECTIVE: The colonic microbiota is altered in patients with colorectal cancer (CRC). We investigated the microbiota composition of patients with colon cancer compared with controls devoid of neoplastic or inflammatory disease and the potential to modify the colonic microbiota with probiotics. DESIGN: Biopsy samples were obtained from the normal mucosa and tumour during colonoscopy from 15 patients with colon cancer. Subsequent patient-matched samples were taken at surgery from the tumour and nearby mucosa from the patients with cancer, eight of whom had received two daily tablets totalling 1.4×1010 CFUs Bifidobacterium lactis Bl-04 and 7×109 CFUs Lactobacillus acidophilus NCFM. Faecal samples were obtained after colonoscopy prior to starting the intervention and at surgery. In addition, 21 mucosal biopsies from non-cancer controls were obtained during colonoscopy followed by later faecal samples. The colonic and faecal microbiota was assessed by 16S rRNA gene amplicon sequencing. RESULTS: The tumour microbiota was characterised by increased microbial diversity and enrichment of several taxa including Fusobacterium, Selenomonas and Peptostreptococcus compared with the control microbiota. Patients with colon cancer that received probiotics had an increased abundance of butyrate-producing bacteria, especially Faecalibacterium and Clostridiales spp in the tumour, non-tumour mucosa and faecal microbiota. CRC-associated genera such as Fusobacterium and Peptostreptococcus tended to be reduced in the faecal microbiota of patients that received probiotics. CONCLUSIONS: Patients with colon cancer harbour a distinct microbiota signature in the tumour tissue and nearby mucosa, which was altered with probiotic intervention. Our results show promise for potential therapeutic benefits in CRC by manipulation of the microbiota. TRIAL REGISTRATION NUMBER: NCT03072641; Results.

Correcting for non-compliance when determining colonic transit time with radio-opaque markers.

The use of radio-opaque markers and abdominal X-ray is the standard method for determining colonic transit time (CTT). However, when there are deviations in the intake of these markers by participants in clinical trials it is desirable to improve observations by introducing corrections, where possible. To date, there is no standard procedure to adjust for such deviations. This report proposes a series of alternatives based on possible scenarios for deviations from the intended intake of radio-opaque markers. The proposed method to correct for missed or delayed consumption of radio-opaque markers can help to increase the accuracy of the CTT measurements in clinical trials.

Lactobacilli vaginal colonisation after oral consumption of Respecta(®) complex: a randomised controlled pilot study.

PURPOSE: The aim of the current pilot study was to determine if oral consumption of a combination of two probiotics; L. acidophilus La-14, L. rhamnosus HN001, and bovine lactoferrin (Respecta(®) complex), would lead to the detection with molecular techniques of the consumed probiotic strains in the vagina. METHODS: Healthy volunteers (40) consumed the study product twice daily for 2 weeks. Vaginal swabs were collected at 0, 1, 2 and 3 weeks and analysed for the consumed organisms by qPCR. RESULTS: Vaginal L. rhamnosus and L. acidophilus levels were significantly increased on days 14 and 21. On days 14 and 21 a significant number of women had increased levels of vaginal L. acidophilus and on days 7 and 21 a significant number of women had increased levels of vaginal L. rhamnosus. CONCLUSIONS: Consumption of L. acidophilus La-14, L. rhamnosus HN001 in combination with bovine lactoferrin leads to vaginal detection; even 1 week after consumption was stopped. This provides a basis for future studies on urogenital tract health.

Xylo-oligosaccharides alone or in synbiotic combination with Bifidobacterium animalis subsp. lactis induce bifidogenesis and modulate markers of immune function in healthy adults: a double-blind, placebo-controlled, randomised, factorial cross-over study.

Prebiotics, probiotics and synbiotics are dietary ingredients with the potential to influence health and mucosal and systemic immune function by altering the composition of the gut microbiota. In the present study, a candidate prebiotic (xylo-oligosaccharide, XOS, 8 g/d), probiotic (Bifidobacterium animalis subsp. lactis Bi-07, 109 colony-forming units (CFU)/d) or synbiotic (8 g XOS+109 CFU Bi-07/d) was given to healthy adults (25-65 years) for 21 d. The aim was to identify the effect of the supplements on bowel habits, self-reported mood, composition of the gut microbiota, blood lipid concentrations and immune function. XOS supplementation increased mean bowel movements per d (P= 0·009), but did not alter the symptoms of bloating, abdominal pain or flatulence or the incidence of any reported adverse events compared with maltodextrin supplementation. XOS supplementation significantly increased participant-reported vitality (P= 0·003) and happiness (P= 0·034). Lowest reported use of analgesics was observed during the XOS+Bi-07 supplementation period (P= 0·004). XOS supplementation significantly increased faecal bifidobacterial counts (P= 0·008) and fasting plasma HDL concentrations (P= 0·005). Bi-07 supplementation significantly increased faecal B. lactis content (P= 0·007), lowered lipopolysaccharide-stimulated IL-4 secretion in whole-blood cultures (P= 0·035) and salivary IgA content (P= 0·040) and increased IL-6 secretion (P= 0·009). XOS supplementation resulted in lower expression of CD16/56 on natural killer T cells (P= 0·027) and lower IL-10 secretion (P= 0·049), while XOS and Bi-07 supplementation reduced the expression of CD19 on B cells (XOS × Bi-07, P= 0·009). The present study demonstrates that XOS induce bifidogenesis, improve aspects of the plasma lipid profile and modulate the markers of immune function in healthy adults. The provision of XOS+Bi-07 as a synbiotic may confer further benefits due to the discrete effects of Bi-07 on the gut microbiota and markers of immune function.

Comparison of bacterial quantities in left and right colon biopsies and faeces.

AIM: To compare quantities of predominant and pathogenic bacteria in mucosal and faecal samples. METHODS: Twenty patients undergoing diagnostic colonoscopy with endoscopically and histologically normal mucosa were recruited to the study, 14 subjects of which also supplied faecal (F) samples between 15 d to 105 d post colonoscopy. Mucosal biopsies were taken from each subject from the midportion of the ascending colon (right side samples, RM) and the sigmoid (left side samples, LM). Predominant intestinal and mucosal bacteria including clostridial 16S rRNA gene clusters IV and XIVab, Bacteroidetes, Enterobacteriaceae, Bifidobacterium spp., Akkermansia muciniphila (A. muciniphila), Veillonella spp., Collinsella spp., Faecalibacterium prausnitzii (F. prausnitzii) and putative pathogens such as Escherichia coli (E. coli), Clostridium difficile (C. difficile), Helicobacter pylori (H. pylori) and Staphylococcus aureus (S. aureus) were analysed by quantitative polymerase chain reaction (qPCR). Host DNA was quantified from the mucosal samples with human glyceraldehyde 3-phosphate dehydrogenase gene targeting qPCR. Paired t tests and the Pearson correlation were applied for statistical analysis. RESULTS: The most prominent bacterial groups were clostridial groups IV and XIVa+b and Bacteroidetes and bacterial species F. prausnitzii in both sample types. H. pylori and S. aureus were not detected and C. difficile was detected in only one mucosal sample and three faecal samples. E. coli was detected in less than half of the mucosal samples at both sites, but was present in all faecal samples. All detected bacteria, except Enterobacteriaceae, were present at higher levels in the faeces than in the mucosa, but the different locations in the colon presented comparable quantities (RM, LM and F followed by P(1) for RM vs F, P(2) for LM vs F and P(3) for RM vs LM: 4.17 ± 0.60 log(10)/g, 4.16 ± 0.56 log(10)/g, 5.88 ± 1.92 log(10)/g, P(1) = 0.011, P(2) = 0.0069, P(3) = 0.9778 for A. muciniphila; 6.25 ± 1.3 log(10)/g, 6.09 ± 0.81 log(10)/g, 8.84 ± 1.38 log(10)/g, P(1) < 0.0001, P(2) = 0.0002, P(3) = 0.6893 for Bacteroidetes; 5.27 ± 1.68 log(10)/g, 5.38 ± 2.06 log(10)/g, 8.20 ± 1.14 log(10)/g, P(1) < 0.0001, P(2) ≤ 0.0001, P(3) = 0.7535 for Bifidobacterium spp.; 6.44 ± 1.15 log(10)/g, 6.07 ±1.45 log(10)/g, 9.74 ±1.13 log(10)/g, P(1) < 0.0001, P(2) ≤ 0.0001, P(3) = 0.637 for Clostridium cluster IV; 6.65 ± 1.23 log(10)/g, 6.57 ± 1.52 log(10)/g, 9.13 ± 0.96 log(10)/g, P(1) < 0.0001, P(2) ≤ 0.0001, P(3) = 0.9317 for Clostridium cluster XIVa; 4.57 ± 1.44 log(10)/g, 4.63 ± 1.34 log(10)/g, 7.05 ± 2.48 log(10)/g, P(1) = 0.012, P(2) = 0.0357, P(3) = 0.7973 for Collinsella spp.; 7.66 ± 1.50 log(10)/g, 7.60 ± 1.05 log(10)/g, 10.02 ± 2.02 log(10)/g, P(1) ≤ 0.0001, P(2) = 0.0013, P(3) = 0.9919 for F. prausnitzsii; 6.17 ± 1.3 log(10)/g, 5.85 ± 0.93 log(10)/g, 7.25 ± 1.01 log(10)/g, P(1) = 0.0243, P(2) = 0.0319, P(3) = 0.6982 for Veillonella spp.; 4.68 ± 1.21 log(10)/g, 4.71 ± 0.83 log(10)/g, 5.70 ± 2.00 log(10)/g, P(1) = 0.1927, P(2) = 0.0605, P(3) = 0.6476 for Enterobacteriaceae). The Bifidobacterium spp. counts correlated significantly between mucosal sites and mucosal and faecal samples (Pearson correlation coefficients 0.62, P = 0.040 and 0.81, P = 0.005 between the right mucosal sample and faeces and the left mucosal sample and faeces, respectively). CONCLUSION: Non-invasive faecal samples do not reflect bacterial counts on the mucosa at the individual level, except for bifidobacteria often analysed in probiotic intervention studies.

Impact of polydextrose on the faecal microbiota: a double-blind, crossover, placebo-controlled feeding study in healthy human subjects.

In this placebo-controlled, double-blind, crossover human feeding study, the effects of polydextrose (PDX; 8 g/d) on the colonic microbial composition, immune parameters, bowel habits and quality of life were investigated. PDX is a complex glucose oligomer used as a sugar replacer. The main goal of the present study was to identify the microbial groups affected by PDX fermentation in the colon. PDX was shown to significantly increase the known butyrate producer Ruminococcus intestinalis and bacteria of the Clostridium clusters I, II and IV. Of the other microbial groups investigated, decreases in the faecal Lactobacillus-Enterococcus group were demonstrated. Denaturing gel gradient electrophoresis analysis showed that bacterial profiles between PDX and placebo treatments were significantly different. PDX was shown to be slowly degraded in the colon, and the fermentation significantly reduced the genotoxicity of the faecal water. PDX also affected bowel habits of the subjects, as less abdominal discomfort was recorded and there was a trend for less hard and more formed stools during PDX consumption. Furthermore, reduced snacking was observed upon PDX consumption. This study demonstrated the impact of PDX on the colonic microbiota and showed some potential for reducing the risk factors that may be associated with colon cancer initiation.

A ingestão de prébioticos previne a malabsorção de ferro e anemia induzidas pela gastrectomia?: Estudo experimental em ratos / Ingestion of prebiotics prevents gastrectomy-induced iron malabsorption and anemia ?: Experimental study in rats

RACIONAL: Ratos gastrectomizados desenvolvem anemia, e a ingestão de galactooligossacarídeo (GOS) e a polidextrose (PDX) aumenta a absorção de ferro e promove a recuperação da anemia em ratos com deficiência de ferro. OBJETIVO: Avaliar se GOS e PDX estimulam a absorção de ferro em ratos gastrectomizados e normais. MÉTODOS: Os ratos foram laparotomizadas (controle falso-operado) e parcialmente gastrectomizados (Billroth II) em grupos de 20 animais. Os animais de ambos os tratamentos foram posteriormente submetidos à dieta controle (AIN-93M) ou a mesma dieta suplementada com GOS e PDX (25 g/kg de dieta cada) durante oito semanas e divididos em quatro subgrupos: sham-operados e gastrectomizados sem GOS e PDX, sham-operados e gastrectomizados com GOS e PDX. Dois animais morreram durante o experimento. Todos os ratos gastrectomizados receberam uma injeção intramuscular de vitamina B-12 a cada duas semanas. Hematócrito (HCT) e concentração de hemoglobina (HGB) foram dosados no início e nos dias 30 e 56 dias após o início da alimentação. No último dia do estudo, o sangue total foi coletado para determinação da concentração de ferro sérico. RESULTADOS: Na dieta com GOS e PDX a excreção de ferro nas fezes foi significativamente menor do que no grupo sem prebióticos. Absorção aparente de ferro e ferro sérico foram maiores nos grupos alimentados com GOS e PDX (ambos grupos: sham operados e gastrectomizados) do que nos grupos não alimentados com GOS e PDX. O HCT e HGB foram significativamente menores nos ratos gastrectomizados que no grupo controle, entretanto, a suplementação com GOS e PDX melhorou os níveis de HGB neste grupo. CONCLUSÃO: A associação de GOS e PDX aumenta a absorção de ferro em ratos shamoperados e gastrectomizados e ainda previne a anemia pós-gastrectomia.

BACKGROUND: The ingestion of two prebiotics, galactooligosaccharide (GOS) and polydextrose (PDX), leads to an increase in iron absorption and promotes recovery from anemia in gastrectomized rats. AIM: To study whether GOS + PDX stimulate iron absorption in gastrectomized and normals rats. METHODS: Rats were laparotomized (sham-operated control) and partially gastrectomized (Billroth II) in groups of 20 each. Animals from both treatments were subsequently fed a control diet (AIN-93M) or the same diet supplemented with GOS and PDX (25 g/Kg of diet each) for eight weeks. They were divided into four subgroups, i.e., sham-operated and gastrectomized without GOS + PDX, sham-operated and gastrectomized with GOS + PDX. Two rats died during the experiment. All gastrectomized rats received an intramuscular injection of vitamin B-12 every two weeks. Hematocrit (HCT) and hemoglobin concentration (HGB) were measured at the start and on day 30 and 56 days after the start of feeding. On the final day of the study, total blood was collected for determination of serum iron concentration. RESULTS: In the diet with GOS + PDX, iron excretion in feces was significantly lower than without the prebiotics. Apparent iron absorption and serum iron was higher in the GOS + PDX fed groups (both sham operated and gastrectomized) than in the non-GOS + PDX fed groups. The HCT and HGB concentrations were significantly lower in gastrectomized rats than in the control group, however, GOS + PDX feeding improved HGB levels in this group. CONCLUSION: The association of the GOS + PDX increase absorption of iron in sham-operated and gastrectomized rats and still prevent postgastrectomy anemia.

Ingestion of polydextrose increase the iron absorption in rats submitted to partial gastrectomy.

PURPOSE: To investigate whether polydextrose stimulates iron absorption in rats submitted to partial gastrectomy and sham operated. METHODS: The rats were submitted to partial gastrectomy (Billroth II) or laparotomy (sham-operated control), in groups of 20 and 20 each respectively. The animals were fed with a control diet (AIN-93M) without polydextrose or a diet containing polydextrose (50g/Kg of diet) for eight weeks. They were divided into four subgroups: sham-operated and Billroth II gastrectomy and with or without polydextrose. Two animals died during the experiment. All rats submitted to gastrectomy received B-12 vitamin (intramuscular) each two weeks. The hematocrit and hemoglobin concentration were measured at the start and on day 30 and 56 after the beginning of the experimental period. At the end of the study, the blood was collected for determination of serum iron concentration. RESULTS: The diet with polydextrose reduced the excretion of iron. Apparent iron absorption was higher in the polydextrose fed groups than in the control group. The haematocrit and haemoglobin concentration were lower after Billroth II gastrectomy rats fed the control diet as compared to the polydextrose diet groups. CONCLUSION: Polydextrose increase iron absorption and prevents postgastrectomy anemia.

Ingestion of polydextrose increase the iron absorption in rats submitted to partial gastrectomy / A ingestão de polidextrose aumenta a absorção de ferro em ratos submetidos à gastrectomia parcial

PURPOSE: To investigate whether polydextrose stimulates iron absorption in rats submitted to partial gastrectomy and sham operated. METHODS: The rats were submitted to partial gastrectomy (Billroth II) or laparotomy (sham-operated control), in groups of 20 and 20 each respectively. The animals were fed with a control diet (AIN-93M) without polydextrose or a diet containing polydextrose (50g/Kg of diet) for eight weeks. They were divided into four subgroups: sham-operated and Billroth II gastrectomy and with or without polydextrose. Two animals died during the experiment. All rats submitted to gastrectomy received B-12 vitamin (intramuscular) each two weeks. The hematocrit and hemoglobin concentration were measured at the start and on day 30 and 56 after the beginning of the experimental period. At the end of the study, the blood was collected for determination of serum iron concentration. RESULTS: The diet with polydextrose reduced the excretion of iron. Apparent iron absorption was higher in the polydextrose fed groups than in the control group. The haematocrit and haemoglobin concentration were lower after Billroth II gastrectomy rats fed the control diet as compared to the polydextrose diet groups. CONCLUSION: Polydextrose increase iron absorption and prevents postgastrectomy anemia.

OBJETIVO: Investigar se a polidextrose estimula a absorção de ferro em ratos submetidos à gastrectomia parcial e sham operados. MÉTODOS: Os ratos foram submetidos à gastrectomia parcial (Billroth II) e à laparotomia (controle sham-operados) em grupos de 20 e 20 cada, respectivamente. Os animais foram alimentados com uma dieta controle (AIN-93M), sem polidextrose ou uma dieta contendo polidextrose (50g/kg de dieta) durante oito semanas. Foram divididos em quatro grupos: sham-operados e com gastrectomia BII e com ou sem polidextrose. Dois animais morreram durante o experimento. Todos os ratos com gastrectomia receberam vitamina B-12 (intramuscular) a cada duas semanas. O hematócrito e a hemoglobina foram dosados no início e nos dias 30 e 56 após o início do período experimental. No final do estudo, o sangue foi coletado para determinação da concentração de ferro sérico. RESULTADOS: A dieta com polidextrose reduziu a excreção de ferro e a absorção de ferro aparente foi maior nos grupos alimentados com polidextrose do que no grupo controle. As dosagens de hematócrito e hemoglobina foram menores em ratos com gastrectomia alimentados com a dieta controle em relação aos grupos de dieta com polidextrose. CONCLUSÃO: A polidextrose aumenta a absorção do ferro e previne a anemia pós-gastrectomia.

Probiotics and immunosenescence: cheese as a carrier.

Oral intake of specific probiotics has been reported to enhance the immunity of the elderly. Earlier studies have used milk or yoghurt as a probiotic carrier. We chose a commercial probiotic cheese to evaluate its potential as a probiotic food. Thirty-one healthy elderly volunteers (21 female, 10 male) aged from 72 to 103 (median 86) consumed a commercial probiotic cheese containing approximately 10(9) CFU day(-1) of Lactobacillus rhamnosus HN001 and Lactobacillus acidophilus NCFM. The 4-week probiotic intervention was preceded by a 2-week consumption of probiotic-free cheese (run-in) and followed by a 4-week wash-out period with the same control cheese. The cytotoxicity of peripheral blood mononuclear cells (PBMCs), the relative numbers of natural killer (NK) and NKT cells in the total PBMCs, and phagocytic activity were assessed. Consumption of the probiotic cheese significantly increased the cytotoxicity of NK cells. A significant increase in phagocytosis was observed for both the control and the probiotic cheese. Cheese was found to be an effective carrier for the study of probiotics, and daily consumption of the probiotic enhanced parameters of innate immunity in elderly volunteers. It remains to be determined whether this enhancement correlates with a beneficial effect on the health of the elderly population.

Effect of overweight on gastrointestinal microbiology and immunology: correlation with blood biomarkers.

A cross-sectional study was carried out in order to compare intestinal microbiological and immunological biomarkers with blood glucose and lipids, satiety-related hormones and inflammatory biomarkers characterising differences between obese and normal weight subjects. Faecal and blood samples were obtained from twenty obese subjects with an average BMI of 32.9 kg/m2 and twenty normal weight subjects with an average BMI of 23.3 kg/m2. Blood insulin, TAG and leptin were significantly elevated, whereas concentrations of HDL and ghrelin were significantly decreased in the obese subjects. Inflammatory status in the obese subjects was characterised by a trend for elevated blood C-reactive protein (CRP; P = 0.06) and IL-6 (P = 0.02). The faecal microbial composition differed between the groups; less sulphate-reducing bacteria (P = 0.05) and a trend for less Bacteroides (P = 0.07) were measured for overweight subjects. Furthermore, an inverse correlation was demonstrated between faecal Bacteroides levels and waist circumference (P = 0.05). The faecal microbial metabolites differed between the groups; increased concentrations of branched-chain fatty acids, phenolics, valeric acid, di- and hydroxy acids were described in the obese subjects. No differences between the measured intestinal inflammatory biomarkers were detected. However, systemic inflammation (CRP and IL-6) was correlated with the faecal concentrations of phenolics and lactic acid (P < 0.05 and 0.05, and P < 0.01 and 0.05, respectively). In summary, weight-related differences were observed both in the intestinal microbial composition and its activity. The role of intestinal signals, such as phenolics and lactic acid in the development of weight-related problems, needs to be studied further.

Dietary polydextrose increases calcium absorption in normal rats / Polidextrose aumenta a absorção de cálcio em ratos

BACKGROUND: Gastric surgery is known to cause bone disorders, possibly related to an impaired capacity for the absorption of dietary calcium. AIM: To verify if polydextrose (PDX) could stimulate calcium absorption in partially gastrectomized and sham operated rats. METHODS: The rats were laparotomized (sham-operated control) or partially gastrectomized (Billroth II), in groups of 20 each. Half in each operated group were fed a control diet (AIN-93M) without PDX or the same diet containing (PDX 50g/Kg of diet) for eight weeks. The rats were divided into four subgroups: sham-operated and gastrectomized without PDX; sham-operated and gastrectomized with PDX. On the final day of the study, total blood was collected for determination of serum calcium concentration. RESULTS: In the diet with PDX, excretion of calcium in the feces was significantly lower than in the groups not receiving PDX, irrespective of the operation. Apparent calcium absorption and serum calcium was higher in the sham operated PDX fed group than in the control group. In sham operated rats, the calcium concentration in bone was higher in the PDX fed group. CONCLUSION: The polydextrose feeding increased calcium absorption and bone calcium concentration in normal rats, which may be relevant for decreasing the risk of osteoporosis. Partially gastrectomy did not affect the bone calcium concentration in 56 days of experimental period.

RACIONAL: A cirurgia gástrica é conhecida por causar desordens ósseas, possivelmente relacionado com a absorção do cálcio na dieta. OBJETIVO: verificar se polidextrose (PDX) poderia estimular a absorção de cálcio em ratos parcialmente gastrectomizados e ratos sham operados. MÉTODOS: Os ratos foram laparotomizadas (sham-operados de controle) ou parcialmente gastrectomizados (Billroth II), em grupos de 20 animais cada. Metade de cada grupo operado foi alimentada com uma dieta controle (AIN-93M) sem PDX ou a mesma dieta contendo (PDX 50g/kg de ração) durante oito semanas. Os animais foram divididos em quatro subgrupos: sham-operados e gastrectomizados sem PDX; sham-operados e gastrectomizados com PDX. No dia final do estudo, sangue foi coletado para determinação da concentração de cálcio sérico. RESULTADOS: Na dieta com PDX, a excreção de cálcio nas fezes foi significativamente menor do que nos grupos que não recebem PDX, independentemente da operação. Absorção aparente de cálcio e cálcio sérico foi maior no sham operados com PDX do que no grupo controle. Em ratos sham operados, a concentração de cálcio nos ossos foi maior no grupo com PDX. CONCLUSÃO: A inclusão de polidextrose na alimentação pode aumentar a absorção de cálcio e aumentar a concentração dele nos ossos em ratos normais, que podem ser relevantes para diminuir o risco de osteoporose. A gastrectomia parcial não afetou a concentração de cálcio ósseo em 56 dias de período experimental.

Influence of a combination of Lactobacillus acidophilus NCFM and lactitol on healthy elderly: intestinal and immune parameters.

With increasing age, a number of physiological changes take place which are reflected in immune and bowel function. These changes may relate to the commonly assumed age-related changes in intestinal microbiota; most noticeably a reduction in bifidobacteria. The current study aimed at modifying the intestinal microbiota with a potential synbiotic on selected immune and microbiota markers. Healthy elderly subjects were randomised to consume during 2 weeks either a placebo (sucrose) or a combination of lactitol and Lactobacillus acidophilus NCFM twice daily in a double-blind parallel trial. After the intervention, stool frequency was higher in the synbiotic group than in the placebo group and a significant increase in faecal L. acidophilus NCFM levels was observed in the synbiotic group, after baseline correction. In contrast to the generally held opinion, the study subjects had faecal Bifidobacterium levels that were similar to those reported in healthy young adults. These levels were, nevertheless, significantly increased by the intervention. Levels of SCFA were not changed significantly. Of the measured immune markers, PGE2 levels were different between treatments and IgA levels changed over time. These changes were modest which may relate to the fact that the volunteers were healthy. Spermidine levels changed over time which may suggest an improved mucosal integrity and intestinal motility. The results suggest that consumption of lactitol combined with L. acidophilus NCFM twice daily may improve some markers of the intestinal microbiota composition and mucosal functions.

Bifidobacterium microbiota and parameters of immune function in elderly subjects.

Faecal and serum samples were collected over a period of 6 months from 55 institutionalized elderly subjects, who were enrolled in a double-blind placebo-controlled study. Participants were randomized in one of the three treatment groups: intervention (two probiotic Bifidobacterium longum strains: 2C and 46), placebo and commercial control (Bifidobacterium lactis Bb-12). The faecal Bifidobacterium microbiota was characterized by genus and species-specific PCR. Serum levels of the cytokines IL-10, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1 were determined by enzyme-linked immunosorbent assay. Each participant harboured on average approximately three different bifidobacterial species. The most frequently detected species were B. longum, Bifidobacterium adolescentis and Bifidobacterium bifidum. Depending on the treatment, the intervention resulted in specific changes in the levels of certain Bifidobacterium species, and positive correlations were found between the different species. Negative correlations were observed between the levels of Bifidobacterium species and the pro-inflammatory cytokine TNF-alpha and the regulatory cytokine IL-10. The presence of faecal B. longum and Bifidobacterium animalis correlated with reduced serum IL-10. The anti-inflammatory TGF-beta1 levels were increased over time in all three groups, and the presence of Bifidobacterium breve correlated with higher serum TGF-beta1 levels. This indicates that modulation of the faecal Bifidobacterium microbiota may provide a means of influencing inflammatory responses.

Disease-dependent adhesion of lactic acid bacteria to the human intestinal mucosa.

Their adhesion to the intestinal mucosa is considered one of the main reasons for the beneficial health effects of specific lactic acid bacteria (LAB). However, the influence of disease on the mucosal adhesion is largely unknown. Adhesion of selected LAB to resected colonic tissue and mucus was determined in patients with three major intestinal diseases (i.e., diverticulitis, rectal carcinoma, and inflammatory bowel disease) and compared to healthy control tissue. All strains were observed to adhere better to immobilized mucus than to whole intestinal tissue. Two strains (Lactobacillus rhamnosus strain GG and L. reuteri) were found to exhibit disease-specific adhesion to intestinal tissue. All tested strains, with the exception of L. rhamnosus strain GG, displayed disease-specific adhesion to intestinal mucus. These results suggest that strains with optimal binding characteristics for a particular intestinal disease can be selected.