SEARCH · PubMed Health

Results for “Probiotic”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

PubMed2003

Immunomodulatory effects of probiotic bacteria DNA: IL-1 and IL-10 response in human peripheral blood mononuclear cells.

A new therapeutic approach for inflammatory bowel diseases is based on the administration of probiotic bacteria. Prokaryotic DNA contains unmethylated CpG motifs which can activate immune responses, but it is unknown whether bacterial DNA is involved in the beneficial effects obtained by probiotic treatment. Peripheral blood mononuclear cells (PBMC) from healthy donors were incubated with pure DNA of eight probiotic strains and with total bacterial DNA from human feces collected before and after probiotic ingestion. Cytokine production was analyzed in culture supernatants. Modification of human microflora after probiotic administration was proven by polymerase chain reaction analysis. Here we show that Bifidobacterium genomic DNA induced secretion of the antiinflammatory interleukin-10 by PBMC. Total bacterial DNA from feces collected after probiotic administration modulated the immune response by a decrease of interleukin-1 beta and an increase of interleukin-10.

Bifidobacterium↗

PubMed2002

Inventing probiotic functional foods for patients with allergic disease.

OBJECTIVE: The primary objective of this review is to discuss the rationale for and applicability of probiotics as part of the nutritional approach to the prevention and management of allergic disease. DATA SOURCES: This review represents a synthesis of recent literature published in the fields of probiotics, nutrition, and allergic disease. STUDY SELECTION: The expert opinions of the authors were used to select the relevant data for the review. RESULTS: The hygiene hypothesis suggests that allergic disease may arise from a lack of counterbalancing microbial exposure at an early age. Thus, the initial compositional development of gut microbiota is considered a key determinant in the development of both the immune responder phenotype and the normal gut barrier functions. A wide range of data documents the specific actions of selected probiotics. The regulatory role of probiotics in allergic disease has been demonstrated as improving the clinical course or preventing the development of atopic eczema in infants given a probiotic-supplemented diet. In addition, certain types of fatty acids and antioxidants have been proposed for protective effects against the development of allergy and to diminish the inflammatory response in allergic disease. CONCLUSIONS: The increase in the prevalence of allergic disease during the past decades is likely to be explained by changes in the environment, including reduced microbial exposure and altered food consumption. Scientifically composed functional foods containing probiotics and other functional components offer a nutritional strategy for both the prevention and the management of allergic disease. Further research is needed to characterize the gut microbiota and to clarify the mechanisms of action that control specific physiologic processes not only in the evolution of allergic disease in at-risk populations but also in the management of allergic diseases.

Complementary Therapies↗

PubMed2003

Probiotics to enhance anti-infective defences in the gastrointestinal tract.

Several clinical studies have demonstrated the therapeutic and/or prophylactic efficacy of specific probiotics against acute viral gastroenteritis and antibiotic-associated diarrhoea (including Clostridium difficile infection). Emerging evidence also suggests beneficial effects against Helicobacter pylori infection. The evidence of efficacy against traveller's diarrhoea remains, however, inconclusive. The precise mechanisms by which probiotics potentiate host gastrointestinal defences and mediate protection are not fully known. There is evidence to suggest, however, that probiotics might contribute to host defence by reinforcing non-immunological defences and stimulating both specific and non-specific host immune responses. Little is known about the relative importance of the probiotic-stimulated mechanisms in host protection. This review summarises the evidence for the anti-infective effects of probiotics and discusses the effect of orally delivered probiotics on non-immunological and immunological defence mechanisms in the host, especially in the gastrointestinal tract.

Animals↗

PubMed2003

Probiotics: what are they? What are their effects on gut physiology?

Probiotics can be defined as microbial cells that have a beneficial effect on the health and well-being of the host. Since the gastrointestinal mucosa is the surface of contact with probiotics, it seems evident that the first effects of probiotics relate to digestive function. A brief review of the literature indicates that probiotics have very few effects on the main physiological functions of the gastrointestinal tract, which are digestion, absorption and propulsion. The main action of probiotics can be summarised as a reinforcement of the intestinal mucosal barrier against deleterious agents. Experimental data indicate that some probiotics reduce pathological alterations in paracellular permeability to large molecules or bacteria, stimulate mucosal immunity, display a trophic action on the mucosa, reduce mucus degradation and interact with mediators of inflammation. Yoghurt may help lactose digestion, and some data needing confirmation indicate a stimulation of water absorption and an acceleration of intestinal transit by some bacteria.

Animals↗

PubMed2002

Probiotics: clinics and/or nutrition.

The primary claim of probiotics is their beneficial influence on the intestinal ecosystem, which, in turn, may provide protection against gastro-intestinal infections. The positive actions on human health include antagonistic activity against pathogens, anti-allergic effects and other effects on the immune system. In recent years, the concept of probiotics evolved from food with beneficial, even if not clearly established, effects on well-being, to the new area of the nutraceuticals or functional foods. This concept was developed further into the biotherapeutics, which are the clinical applications of probiotic microorganisms originally selected for food use. Whereas several of these health claims remain controversial, well-planned clinical trials increasingly support the claims for some carefully selected probiotic strains. Aim of this review is to provide a first attempt to evaluate these two areas of use of probiotics and to draw a borderline between them. Only a more in-depth knowledge of the mechanisms underlying the probiotic effects will allow a clear discrimination between the food use and the clinical use.

Bifidobacterium↗

PubMed2006

Impact of consuming a milk drink containing a probiotic on mood and cognition.

OBJECTIVE: The impact on mood and memory of consuming a probiotic containing milk drink, or a placebo, was examined as, previously, a poor mood has been found to correlate with the frequency of constipation. DESIGN: A double-blind placebo-controlled trial with random allocation of subjects. SETTING: Subjects went about their normal life in the community apart from three visits to the laboratory. SUBJECTS: One hundred and thirty-two healthy members of general population, mean age 61.8 years, volunteered in response to local media coverage. One hundred and twenty-four finished the trial. INTERVENTION: For a 3-week period, either a probiotic containing milk drink, or a placebo, were consumed daily. Mood and cognition were measured at baseline, and after 10 and 20 days of consumption. RESULTS: At baseline those who reported themselves to be less frequently constipated were more clearheaded, confident and elated. Although the taking of the probiotic did not generally change the mood, this appeared to be a reflection of the generally good mood in this sample. When those in the bottom third of the depressed/elated dimension at baseline were considered, they selectively responded by reporting themselves as happy rather than depressed after taking the probiotic. The intervention did not, however, influence the reported frequency of defaecation, probably a reflection of the initially low incidence of constipation. An unexpected and possibly chance finding was that the consumption of probiotics resulted in a slightly-poorer performance on two measures of memory. CONCLUSIONS: The consumption of a probiotic-containing yoghurt improved the mood of those whose mood was initially poor. This improvement in mood was not, however, associated with an increased frequency of defaecation.

Affect↗

PubMed2006

Probiotics and commensals reverse TNF-alpha- and IFN-gamma-induced dysfunction in human intestinal epithelial cells.

BACKGROUND & AIMS: Commensal bacteria are crucial for the development of the mucosal immune system. Probiotics are commensals with special characteristics and may protect mucosal surfaces against pathogens. Pathogens cause significant phenotypic alterations in infected epithelial cells, and probiotics reverse these deleterious responses. We hypothesized that probiotics and/or commensals may also reverse epithelial damage produced by cytokines. METHODS: Human intestinal epithelial cells were exposed basolaterally to interferon (IFN)-gamma (10(3) U/mL) or tumor necrosis factor (TNF)-alpha (10 ng/mL) for up to 48 hours and assessed for ion transport, transepithelial resistance (TER), and epithelial permeability in the presence or absence of probiotics (Streptococcus thermophilus [ST] and Lactobacillus acidophilus [LA]), or the commensal, Bacteroides thetaiotaomicron (BT). RESULTS: Agonist-stimulated chloride secretion was inhibited by IFN-gamma, an effect prevented by ST/LA or BT. The ability of ST/LA or BT to restore Cl(-) secretion was blocked by inhibitors of p38 MAPK, ERK1, 2, and PI3K. The cystic fibrosis transmembrane conductance regulator (CFTR) and the NKCC1 cotransporter were down-regulated by IFN-gamma, and ST/LA pretreatment reversed this effect. Both TNF-alpha and IFN-gamma significantly reduced TER and increased epithelial permeability, effects prevented by ST/LA or BT. A Janus kinase (JAK) inhibitor synergistically potentiated effects of ST/LA or BT on TER and permeability, but p38, ERK1, 2, or PI3K inhibition did not. Finally, only probiotic-treated epithelial cells exposed to cytokines showed reduced activation of SOCS3 and STAT1,3. CONCLUSIONS: Deleterious effects of TNF-alpha and IFN-gamma on epithelial function are prevented by probiotic, and to a lesser extent, commensal pretreatment. These data extend the spectrum of effects of such bacteria on intestinal epithelial function and may justify their use in inflammatory disorders.

Bacteroides↗

PubMed2002

[Probiotics in gastroenterology].

Probiotics are defined as live microorganisms of human origin. Their use may favorably influence human health and ameliorate or prevent certain diseases. Prebiotics are non-digestible foodstuffs (fiber, oligofructans - "colonic foods"), which enter the colon and are metabolized by the probiotics. Probiotics should fulfill the following criteria: Phenotypic and genotypic classification, no pathogenic properties, human origin, application in the living state, resistance to gastric acid and bile, ability to adhere to colonocytes, ability to colonize the gut, clinically proved favorable health-effect, and safety. Experimental and clinical studies supplied evidence of the possible use of probiotics in the following diseases: Traveler's diarrhea, antibiotic-associated diarrhea, relapsing Clostridium difficile colitis, infantile diarrhea, rotavirus enteritis, inflammatory bowel disease, irritable bowel syndrome, colon cancer, peritonitis, acute pancreatitis, and diarrhea associated with HIV infection. Probiotics displayed the following effects in these studies: Involvement in production of essential nutrients of the colonic mucosa, beneficial effect on intestinal immunity, recovery of the disturbed gut mucosal barrier and prevention of microbial translocation, elimination of toxins and eradication of microbial pathogens, production of steroids from cholesterol and reduction of its pool in circulation, participation in regulation of intestinal functions, reduced incidence of chemically induced colon tumors in rodents. Probiotics open new therapeutic modalities in a number of diseases and it may be expected that their importance will increase with growing knowledge and experience.

Colitis↗

PubMed2005

[Probiotics--from empirical medicine to therapeutic standard].

Due to the lack of proven efficacy and an unidentified mode of action, probiotics were dismissed by the traditional medical sector for many years. In the meantime, the clinical efficacy of some probiotics has clearly been substantiated in GCP-compliant studies. In addition, modes of action have been demonstrated which prove the effects of probiotics on a cellular level and replace the concept of "restoring the disturbed intestinal microbial balance". Different probiotics have distinct modes of action and the clinical efficacy of various probiotics has been proven in distinct indications. Today, some probiotics represent therapeutic standards in certain indications.

Clinical Trials as Topic↗

PubMed2004

Validation of the official control method based on Polymerase Chain Reaction (PCR) for identification of authorised probiotic yeast in animal feed.

Council Directive 70/524/EEC regulates the application of probiotic (microorganisms) additives in feeding stuffs. In the present study a method for the differentiation and strain identification of authorised probiotic Saccharomyces cereviseae strains in feeding stuffs by Polymerase Chain Reaction (PCR) was validated. Four different samples of animal feeding stuffs containing yeast at levels between 10(5) to 10(7) CFU/g were examined. Samples were enumerated on chloramphenicol glucose yeast extract agar and colonies were selected from these plates for DNA extraction and subsequent analysis. The PCR method using delta sequence primers produced an 'amplified sequence polymorphism' characteristic for the test strain. Feeds supplemented with one of four probiotic yeast strains each were analysed by seven of nine invited laboratories. All laboratories returned valid results with the exception of one laboratory that had insufficiently separated bands on the gel. The method had a good reproducibility for probiotic yeast isolates from feed of all four authorised probiotic yeast strains (APYS) CBS 493.94, APYS CNCM 1-1079, APYS CNCM 1-1077, APYS NCYC SC47 and of a commercially available yeast reference strain, NCYC 81. The PCR method is to be considered by CEN and ISO as official control method for identification of authorised probiotic Saccharomyces cerevisiae strains from feeding stuffs.

Animal Feed↗

PubMed2002

Probiotics: on-going research on atopic individuals.

The challenge for the modern health care system is to fight against the increasing prevalence of atopic disease. The introduction of scientifically composed probiotic functional foods for prophylactic or therapeutic purposes could be one solution. Probiotics are live microbial food supplements or components of bacteria which have beneficial effects on human health. Specific strains have been demonstrated to exert powerful anti-pathogenic, anti-inflammatory and anti-allergic effects. The hygiene hypothesis suggests that atopic disease may arise from a lack of counterbalancing microbial exposure at an early age. The initial compositional development of the gut microflora is considered a key determinant of the development of both the immune responder phenotype and normal gut barrier functions. The regulatory role of probiotics in human allergic disease was first emphasised in the demonstration of a suppressive effect on lymphocyte proliferation and interleukin-4 generation in vitro. Subsequently, a significant improvement in the clinical course of atopic eczema was reported in infants given a probiotic-supplemented diet. The potential of probiotics to reduce the risk of atopic disease has recently been demonstrated in a double-blind, placebo-controlled study: probiotics administered pre- and postnatally for 6 months to at-risk subjects reduced the prevalence of atopic eczema to half of that observed in infants receiving placebo. Ongoing research is directed towards the development of novel techniques to characterise the gut microflora. Future research will clarify the mechanisms to control specific physiological processes in the evolution of atopic disease in at-risk populations or in the management of allergic diseases.

Diet↗

PubMed2002

Application of molecular biological methods for studying probiotics and the gut flora.

Increasingly, the microbiological scientific community is relying on molecular biology to define the complexity of the gut flora and to distinguish one organism from the next. This is particularly pertinent in the field of probiotics, and probiotic therapy, where identifying probiotics from the commensal flora is often warranted. Current techniques, including genetic fingerprinting, gene sequencing, oligonucleotide probes and specific primer selection, discriminate closely related bacteria with varying degrees of success. Additional molecular methods being employed to determine the constituents of complex microbiota in this area of research are community analysis, denaturing gradient gel electrophoresis (DGGE)/temperature gradient gel electrophoresis (TGGE), fluorescent in situ hybridisation (FISH) and probe grids. Certain approaches enable specific aetiological agents to be monitored, whereas others allow the effects of dietary intervention on bacterial populations to be studied. Other approaches demonstrate diversity, but may not always enable quantification of the population. At the heart of current molecular methods is sequence information gathered from culturable organisms. However, the diversity and novelty identified when applying these methods to the gut microflora demonstrates how little is known about this ecosystem. Of greater concern is the inherent bias associated with some molecular methods. As we understand more of the complexity and dynamics of this diverse microbiota we will be in a position to develop more robust molecular-based technologies to examine it. In addition to identification of the microbiota and discrimination of probiotic strains from commensal organisms, the future of molecular biology in the field of probiotics and the gut flora will, no doubt, stretch to investigations of functionality and activity of the microflora, and/or specific fractions. The quest will be to demonstrate the roles of probiotic strains in vivo and not simply their presence or absence.

Bacterial Typing Techniques↗

PubMed2003

Probiotics: a perspective on problems and pitfalls.

Therapeutic manipulation of gut flora with probiotics promises to be a useful strategy for several disorders, including infectious, inflammatory and neoplastic conditions. However, there are large gaps in the knowledge of the normal flora and of the optimal use of probiotic products. At present, there is no reliable in vitro predictor of in vivo efficacy of putative probiotics. Indeed, probiotic performance should be defined in the context of the disease indication for which it is intended. This will require rigorous prospective clinical trials. In addition, guidelines for routine clinical use of probiotics are confounded by insufficient data on optimum strain selection, dose, delivery vehicle and monitoring. Before the promise can be fulfilled, problems and potential pitfalls with probiotic therapy need resolution.

Colitis, Ulcerative↗

PubMed2005

Effects of feeding antibiotic-free creep feed supplemented with oligofructose, probiotics or synbiotics to suckling piglets increases the preweaning weight gain and composition of intestinal microbiota.

The objective of this study was to determine whether feeding an antibiotic-free creep feed supplemented with either oligofructose, probiotics or synbiotics to suckling piglets influences growth performance, the gut microflora, gut morphology and hematological traits at weaning. Twenty sows with 10 piglets each were randomly assigned to one of four treatments. The treatments consisted of a control (antibiotic-free) diet, 0.2% oligofructose (OF), 0.3% probiotics or 0.5% synbiotics (mixture of 0.2% OF+0.3% probiotics). Piglets were offered the diet ad libitum from 7 d after birth until one day after weaning (21 d of age). At the day after weaning, blood samples were collected from the jugular vein to determine the immune response. Digesta samples of the ileum and colon were collected to determine the microbial composition. Tissue segments from the duodenum and ileum were collected for morphometric measurements of the small intestine. The average daily weight gain was significantly higher for piglets fed the OF or synbiotics diet compared with the pigs fed the control diet. The hematological traits (the concentration of lymphocytes and neutrophils in whole blood) were not affected by the diet. Piglets fed the OF, probiotics or synbiotics diet had a significantly decreased number of total coliform bacteria in the colon. Feeding OF, probiotics or synbiotics significantly increased the population of bifidobacteria in the ileum compared to the control. In the colon, the probiotics and synbiotics diet significantly increased the number of bifidobacteria compared with the control diet. The results of this experiment showed that supplementation of oligofructose or synbiotics to an antibiotic-free creep feed during the preweaning period affected gut microbial population and performance of piglets.

Animal Feed↗

PubMed2001

Probiotics in human disease.

Western civilization is facing a progressive increase in immune-mediated, gut-related health problems, such as allergies and autoimmune and inflammatory diseases, and genetic factors are an unlikely explanation for these rapid increases in disease incidence. Two environmental factors that relate to the modern lifestyle in Western societies are hygiene and nutrition. There has been a decline in the incidence of microbial stimulation by infectious diseases as a result of improved hygiene, vaccination, and antimicrobial medication. In the past, methods of food preservation involved either the natural fermentation or drying of foods; thus, the human diet once contained several thousand times more bacteria than it does today. The development of probiotic, functional foods aims to "kill two birds with one stone," which is accomplished by providing a microbial stimulus to the host immune system by means of beneficial live microorganism cultures that are characteristic of the healthy, human gut microflora, ie, probiotics. Probiotic bacteria were shown to reinforce the different lines of gut defense, which are immune exclusion, immune elimination, and immune regulation. They were also shown to stimulate nonspecific host resistance to microbial pathogens, thereby aiding in pathogen eradication. Consequently, the best documented clinical application of probiotics is in the treatment of acute diarrhea. In humans, documented effects were reported for the alleviation of intestinal inflammation, normalization of gut mucosal dysfunction, and down-regulation of hypersensitivity reactions. These data show that probiotics promote endogenous host defense mechanisms. Thus, modification of gut microflora by probiotic therapy may offer a therapeutic potential in clinical conditions associated with gut-barrier dysfunction and inflammatory response.

Diet↗

PubMed2006

Probiotic supplementation reduces a biomarker for increased risk of liver cancer in young men from Southern China.

BACKGROUND: In vitro and in vivo studies suggest that selected strains of probiotic bacteria can form tight complexes with aflatoxin B(1) and other carcinogens. OBJECTIVE: The aim of the present study was to determine whether administration of probiotic bacteria could block the intestinal absorption of aflatoxin B(1) and thereby lead to reduced urinary excretion of aflatoxin B(1)-N(7)-guanine (AFB-N(7)-guanine), a marker for a biologically effective dose of aflatoxin exposure. Elevated urinary excretion of this aflatoxin-DNA adduct is associated with an increased risk of liver cancer. DESIGN: Ninety healthy young men from Guangzhou, China, were randomly assigned to 2 groups; one group received a mixture of Lactobacillus rhamnosus LC705 and Propionibacterium freudenreichii subsp. shermanii strains 2 times/d for 5 wk, and the other group received a placebo preparation. The subjects provided 4 urine samples: at baseline, at 3 and 5 wk after starting the supplementation, and at the end of the 5-wk postintervention period. RESULTS: The percentage of samples with negative AFB-N(7)-guanine values tended to be higher in the probiotic group than in the placebo group during the 5-wk intervention period (odds ratio: 2.63, P = 0.052), and a statistically significant decrease in the concentration of urinary AFB-N(7)-guanine was observed in the probiotic group. The reduction was 36% at week 3 and 55% at week 5. The geometric means for the probiotic and placebo groups were 0.24 and 0.49 ng AFB-N(7)-guanine/mL, respectively, during the intervention period (P = 0.005). CONCLUSION: A probiotic supplement reduces the biologically effective dose of aflatoxin exposure and may thereby offer an effective dietary approach to decrease the risk of liver cancer.

Aflatoxin B1↗

PubMed2006

Probiotics for prevention of recurrent vulvovaginal candidiasis: a review.

Vulvovaginal candidiasis (VVC) is a common infection affecting the quality of life of many women. Probiotics have been investigated as possible agents for the prevention of recurrences of VVC. We reviewed the available literature. In some studies the development of VVC was associated with either a low number of lactobacilli in the vagina or with the presence of H2O2-non-producing vaginal lactobacilli, although there are a few studies not supporting these statements. In addition, in vitro studies have shown that lactobacilli can inhibit the growth of Candida albicans and/or its adherence on the vaginal epithelium. The results of some clinical trials support the effectiveness of lactobacilli, especially Lactobacillus acidophilus, Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14, administered either orally or intravaginally in colonizing the vagina and/or preventing the colonization and infection of the vagina by C. albicans, while the results of a small number of clinical trials do not corroborate these findings. Nevertheless, most of the relevant clinical trials had methodological problems such as small sample size, no control group (placebo) and included women without confirmed recurrent VVC, and thus they are not reliable for drawing definitive conclusions. Thus, the available evidence for the use of probiotics for prevention of recurrent VVC is limited. However, the empirical use of probiotics may be considered in women with frequent recurrence of VVC (more than three episodes per year), especially for those who have adverse effects from or contraindications for the use of antifungal agents, since adverse effects of probiotics are very rare. In any case women should be clearly informed about the unproven usefulness of probiotics for this purpose. In conclusion, despite the promising results of some studies, further research is needed to prove the effectiveness of probiotics in preventing the recurrences of VVC and to allow their wide use for this indication.

Antibiosis↗

PubMed2006

Probiotics for children: use in diarrhea.

The use of probiotics in diarrheal diseases of children is increasing. Probiotics, mostly lactic acid bacteria such as Lactobacilli and Bifidobacteria, but also the yeast Saccharomyces boulardii, have been tried in many double-blinded, randomized, placebo-controlled studies, and several well-conducted meta-analyses are now available. There is some evidence of efficacy in the prevention of community-acquired and nosocomial diarrhea. More solid evidence of efficacy is found in the treatment of sporadic, infectious diarrhea, where several probiotics, and especially Lactobacillus GG, have been found capable of reducing by approximately 1 day the duration of diarrhea, shorten the initial phase of watery stools, and reducing hospital stay in developed countries. The effect is best documented in viral diarrheas. Although there are valid conceptual premises for probiotics to be helpful in inflammatory bowel diseases, only 1 trial has been published in children, showing Lactobacillus GG not to be superior to placebo in maintaining remission of Crohn disease. All considered, more research is needed for a better understanding of the role of probiotics in gastrointestinal diseases of children, addressing issues such as pharmacokinetics, mechanism of action, and role of specific probiotics, alone or in combination, in different disorders.

Acute Disease↗