Lactobacillus paracasei strain ST11 has no effect on rotavirus but ameliorates the outcome of nonrotavirus diarrhea in children from Bangladesh

The use of probiotic strains in caries prevention: a systematic review

This paper aims to provide a systematic review of the caries-prevention effect of probiotics in human. The hypothesis was that the administration of probiotic strains might play a role in caries lesion prevention and in the control of caries-related risk factors. The main relevant databases (Medline, Embase) were searched. Quality of the Randomized Clinical Trials (RCTs) was classified using the “Consolidated Standards of Reporting Trials” (CONSORT) checklist and the Impact Factor (IF) value of each journal was recorded. Sixty-six papers were identified, and 23 fulfilled the inclusion criteria. Only three studies had caries lesion development as outcome, all the others reported caries risk factors as interim evaluation. Using the CONSORT Score, the papers were coded as 4 excellent, 9 good and 10 poor. The mean IF value recorded was 1.438. Probiotics may play a role as antagonistic agent on mutans streptococci (MS), acidogenic/aciduric bacteria that contributes to the caries process. In two-thirds of the selected papers, probiotics have demonstrated the capacity to reduce MS counts in saliva and/or plaque in short-term. The effect of probiotics on the development of caries lesion seems encouraging, but to date, RCTs on this topic are insufficient to provide scientific clinical evidence.

Probiotics and prebiotics in pediatric diarrheal disorders

INTRODUCTION

In pediatrics, prebiotics and/or probiotics are added to infant formula, mainly to prevent diseases such as diarrheal disorders. Probiotic food supplements and medication are frequently used in the treatment of diarrheal disorders. This paper reviews the recent published evidence on these topics.

AREAS COVERED

Relevant literature published using PubMed and CINAHL was collected and reviewed. Recent review papers were give special attention.

EXPERT OPINION

The addition of pre- and/or probiotics to infant formula seems not harmful, but the evidence for benefit is limited. Most probiotics are commercialized as food supplements, and therefore do not qualify for medication legislation. Worldwide, Saccharomyces boulardii is the only strain which is registered as "medication" in the majority of countries. Efficacy data can only be considered if performed with the commercialized product. Some products reduce the risk for antibiotic-associated diarrhea and reduced the duration of acute infectious diarrhea with about 24 h. Overall, data in the other indications (inflammatory bowel disease, irritable bowel syndrome) are disappointing, although there are some recent promising results. The use of food supplements as medication opens the discussion to create a category of "medical food."

Novel probiotic Bifidobacterium longum subsp. infantis CECT 7210 strain active against rotavirus infections

Rotavirus is the leading cause of severe acute gastroenteritis among children worldwide. It is well known that breast-feeding and vaccination afford infants protection. Since breast-feeding has drastically decreased in developed countries, efforts have been focused on the potential use of probiotics as preventive agents. In this study, a novel Bifidobacterium longum subsp. infantis strain was isolated from infant feces and selected, based on its capacity to inhibit in vitro rotavirus Wa replication (up to 36.05% infectious foci reduction) and also to protect cells from virus infection (up to 48.50% infectious foci reduction) in both MA-104 and HT-29 cell lines. Furthermore, studies using a BALB/c mouse model have proved that this strain provides preliminary in vivo protection against rotavirus infection. The strain has been deposited in the Spanish Type Culture Collection under the accession number CECT 7210. This novel strain has the main properties required of a probiotic, such as resistance to gastrointestinal juices, biliary salts, NaCl, and low pH, as well as adhesion to intestinal mucus and sensitivity to antibiotics. The food safety status has been confirmed by the absence of undesirable metabolite production and in acute ingestion studies of mice. Overall, these results demonstrate that Bifidobacterium longum subsp. infantis CECT 7210 can be considered a probiotic able to inhibit rotavirus infection.

Treatment of acute diarrhea with Saccharomyces boulardii in infants

OBJECTIVE

The aim of the study was to determine whether an oral treatment with a commercial pharmaceutical product containing Saccharomyces boulardii would reduce the duration of diarrhea in infants with acute diarrhea.

PATIENTS AND METHODS

In the present double-blind, placebo-controlled study, 186 infants, 6 to 48 months old and hospitalized within 72 hours after the onset of acute diarrhea in 2 hospitals in Goiânia, Goiás, Brazil, were randomly assigned to receive twice per day for 5 days 200 mg of a commercial pharmaceutical product containing 4 × 10 viable cells of S boulardii or a placebo. Stool samples were submitted to search for rotavirus. Among the 176 infants who completed the trial, those treated with S boulardii (90) showed a reduction in diarrhea duration (P < 0.05) when compared with the placebo group (86).

RESULTS

The present study shows a reduction in diarrhea duration when S boulardii was given to children within 72 hours after the onset of acute diarrhea.

CONCLUSIONS

The present study suggests a complementary treatment of acute diarrhea in infants with daily oral doses of S boulardii.

Tolerance, safety, and effect on the faecal microbiota of an enteral formula supplemented with pre- and probiotics in critically ill children

OBJECTIVES

The aim of this study was to demonstrate the tolerance and safety of an enteral formula containing prebiotics/probiotics, and its effect on the faecal microbiota in critically ill children.

SUBJECTS AND METHODS

Ninety-four patients between 1 and 3 years old under mechanical ventilation requiring enteral feeding were randomised to receive either a test formula containing a synbiotic blend (composed of 2 probiotic strains [Lactobacillus paracasei NCC 2461 and Bifidobacterium longum NCC 3001], fructooligosaccharides [FOS], inulin, and Acacia gum), or a control formula. Patients remained in the intensive care unit for 7 days and were examined at day 14. Tolerance was assessed by overall caloric intake and time to reach caloric goal. Safety was assessed by abdominal distention, vomiting, and stool frequency. Microbiota was analysed by culture- and molecular-based methods.

RESULTS

Overall caloric intake and time to reach caloric goal were similar between groups (noninferiority was shown). Abdominal distention, vomiting, and stool frequency were not affected by the supplementation with pre- and probiotics. Faecal bifidobacteria were higher in the test group at the end of the study. A similar trend was observed for total lactobacilli. L paracasei NCC 2461 and B longum NCC 3001 were detected in 80.4% and 17% of the test group patients, respectively. Enterobacteria levels remained unchanged during hospitalisation in the control group but diminished in the test group.

CONCLUSIONS

The enteral formula supplemented with synbiotics was well tolerated by children in intensive care units; it was safe and produced an increase in faecal bacterial groups of previously reported beneficial effects.

Lactobacillus paracasei reduces intestinal inflammation in adoptive transfer mouse model of experimental colitis

Studies showed that specific probiotics provide therapeutic benefits in inflammatory bowel disease. In vitro evidence suggested that Lactobacillus paracasei also called ST11 (CNCM I-2116) is a potent strain with immune modulation properties. However, little is known about its capacity to alleviate inflammatory symptoms in vivo In this context, the main objective of this study was to investigate the role of ST11 on intestinal inflammation using the adoptive transfer mouse model of experimental colitis. Rag2^−/− recipient mice were fed with ST11 (10⁹ CFU/day)a month prior toinduce colitis by adoptive transfer of naive T cells. One month later, in clear contrast to nonfed mice, weight loss was significantly reduced by 50% in ST11-fed mice. Further analysis of colon specimens revealed a significant reduction neutrophil infiltration and mucosal expression of IL1β, IL-6, and IL12 proinflammatory cytokines, whereas no consistent differences in expression of antibacterial peptides or tight junction proteins were observed between PBS and ST11-fed mice. All together, our results demonstrate that oral administration of ST11 was safe and had a significant preventive effect on colitis. We conclude that probiotics such as Lactobacillus paracasei harbor worthwhile in vivo immunomodulatory properties to prevent intestinal inflammation by nutritional approaches.

Probiotics for photoprotection

Specific strains of probiotic, have been identified as beneficial to influence the composition and/or metabolic activity of the endogenous microbiota and some of these strains have been also shown to inhibit the growth of a wide range of enteropathogens. The first aim of using probiotics has been to improve the composition of the intestinal microbiota from a potentially harmful composition towards a composition that would be beneficial to the host.Beyond their capacity to influence positively the composition of the intestinal microbiota, several lines of evidence suggest that some probiotic bacteria can modulate the immune system both at the local and systemic levels thereby improving immune defense mechanisms and/or downregulate immune disorders such as allergies or intestinal inflammation.Skin reflects the general health status and aging. Different human trials widely suggest that probiotic supplementation might be useful in the management of atopic dermatitis. Based on these properties it appears that, beyond the gut, probiotics might exert their benefits at the skin level.In a randomized double blind placebo-controlled clinical trial, we investigated whether the probiotic bacteria Lactobacillus johnsonii NCC 533 (La1) could modulate the cutaneous immune homeostasis altered by solar-simulated UV exposure in humans. After, UV exposure to twice 1.5 MED, we demonstrated that La1 intake facilitated an earlier recovery of Epidermal cells allostimulatory function. Thus, this clinical data strengthen the assumption that certain probiotics can contribute to modulate skin immune system leading to the preservation of the skin homeostasis. Altogether the data affords the possibility of designing new strategies based on a nutritional approach for the prevention of UV-induced damaging effects.

The incidence of necrotizing enterocolitis is increased following probiotic administration to preterm pigs

Preterm birth and necrotizing enterocolitis (NEC) is associated with inappropriate gut colonization and immunity, which may be improved by probiotic bacteria. Using a preterm pig model of NEC, we investigated the effects of probiotics on intestinal structure, function, microbiology, and immunology in the immediate postnatal period. Just after birth, caesarean-delivered preterm pigs were inoculated with Lactobacillus paracasei, Bifidobacteria animalis, and Streptococcus thermophilus (total 2.4 × 10(10)/d) either as live (ProLive, n = 14) or gamma-irradiated dead bacteria (ProDead, n = 12) and compared with controls (n = 14). All pigs received parenteral nutrition for 2 d followed by enteral formula feeding until tissue collection on d 5. Compared with control pigs, intestinal weight was lower and NEC incidence was higher in both groups given probiotics (64-67 vs. 14%; P<0.01). Hexose absorption, brush border enzyme activities, and gut barrier function were lower in the ProDead group compared with the other groups (P < 0.05), whereas live probiotics induced higher expression of the proinflammatory cytokines IL-1α and IL-6 (P < 0.05). Probiotics minimally affected gut colonization, except that live probiotics induced a higher density of B. animalis and lower bacterial diversity in the distal intestinal mucosa and lower SCFA concentrations in the colon (P < 0.05). The detrimental effects of probiotic bacteria in this study may relate to the specific strain and dose combination and may have involved the very immature gut immune system and low NEC incidence in the control group. It remains to be determined whether similar adverse responses to probiotics occur in preterm infants.

Bifidobacterium longum lysate, a new ingredient for reactive skin

Reactive skin is characterized by marked sensitivity to physical (heat, cold, wind) or chemical (topically applied products) stimuli and by the impairment of the skin barrier's ability to repair itself. Several lines of evidence suggest that beyond their capacity to positively influence the composition of intestinal microbiota, some probiotic bacteria can modulate the immune system both at local and systemic levels, thereby improving immune defense mechanisms and/or down-regulating immune disorders such as allergies and intestinal inflammation. Several recent human clinical trials clearly suggest that probiotic supplementation might be beneficial to the skin. Using a probiotic lysate, Bifidobacterium longum sp. extract (BL), we demonstrated first in vitro, and then in a clinical trial, that this non-replicating bacteria form applied to the skin was able to improve sensitive skin. The effect of BL were evaluated first on two different models. Using ex vivo human skin explant model we found a statistically significant improvement versus placebo in various parameters associated with inflammation such as a decrease in vasodilation, oedema, mast cell degranulation and TNF-alpha release. Moreover, using nerve cell cultures in vitro, we showed that after 6 h of incubation in culture medium (0.3-1%), the probiotic lysate significantly inhibited capsaicin-induced CGRP release by neurones. Then, a topical cream containing the active extract was tested in a randomized, double-blind, placebo-controlled trial. Sixty-six female volunteers with reactive skin were randomly given either the cream with the bacterial extract at 10% (n = 33) or the control cream (n = 33). The volunteers applied the cream to the face, arms and legs twice a day for two months. Skin sensitivity was assessed by stinging test (lactic acid) and skin barrier recovery was evaluated by measuring trans-epidermal water loss following barrier disruption induced by repeated tape-stripping at D1, D29 and D57. The results demonstrated that the volunteers who applied the cream with bacterial extract had a significant decrease in skin sensitivity at the end of the treatment. Moreover, the treatment led to increase skin resistance against physical and chemical aggression compared to the group of volunteers who applied the control cream. Notably, the number of strippings required to disrupt skin barrier function was significantly increased for volunteers treated with the active cream. Clinical and self-assessment scores revealed a significant decrease in skin dryness after 29 days for volunteers treated with the cream containing the 10% bacterial extract. Since in vitro studies demonstrated that, on one hand, isolate sensitive neurones release less CGRP under capsaicin stimulation in the presence of the bacterial extract and, on the other hand, increased skin resistance in volunteers applying the test cream, we speculate that this new ingredient may decrease skin sensitivity by reducing neurone reactivity and neurone accessibility. The results of this studies demonstrate that this specific bacterial extract has a beneficial effect on reactive skin. These findings suggest that new approaches, based on a bacteria lysate, could be developed for the treatment and/or prevention of symptoms related to reactive skin.

Probiotics for treating acute infectious diarrhoea

BACKGROUND

Probiotics may offer a safe intervention in acute infectious diarrhoea to reduce the duration and severity of the illness.

OBJECTIVES

To assess the effects of probiotics in proven or presumed acute infectious diarrhoea.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group's trials register (July 2010), the Cochrane Controlled Trials Register (The Cochrane Library Issue 2, 2010), MEDLINE (1966 to July 2010), EMBASE (1988 to July 2010), and reference lists from studies and reviews. We also contacted organizations and individuals working in the field, and pharmaceutical companies manufacturing probiotic agents.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing a specified probiotic agent with a placebo or no probiotic in people with acute diarrhoea that is proven or presumed to be caused by an infectious agent.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the methodological quality of the trial and extracted data. Primary outcomes were the mean duration of diarrhoea, stool frequency on day 2 after intervention and ongoing diarrhoea on day 4. A random-effects model was used.

MAIN RESULTS

Sixty-three studies met the inclusion criteria with a total of 8014 participants. Of these, 56 trials recruited infants and young children. The trials varied in the definition used for acute diarrhoea and the end of the diarrhoeal illness, as well as in the risk of bias. The trials were undertaken in a wide range of different settings and also varied greatly in organisms tested, dosage, and participants' characteristics. No adverse events were attributed to the probiotic intervention.Probiotics reduced the duration of diarrhoea, although the size of the effect varied considerably between studies.The average of the effect was significant for mean duration of diarrhoea (mean difference 24.76 hours; 95% confidence interval 15.9 to 33.6 hours; n=4555, trials=35) diarrhoea lasting ≥4 days (risk ratio 0.41; 0.32 to 0.53; n=2853, trials=29) and stool frequency on day 2 (mean difference 0.80; 0.45 to 1.14; n=2751, trials=20).The differences in effect size between studies was not explained by study quality, probiotic strain, the number of different strains, the viability of the organisms, dosage of organisms, the causes of diarrhoea, or the severity of the diarrhoea, or whether the studies were done in developed or developing countries.

AUTHORS' CONCLUSIONS

Used alongside rehydration therapy, probiotics appear to be safe and have clear beneficial effects in shortening the duration and reducing stool frequency in acute infectious diarrhoea. However, more research is needed to guide the use of particular probiotic regimens in specific patient groups.

Are probiotics a feasible intervention for prevention of diarrhoea in the developing world?

With more than 1.4 million of the 9 million child deaths being attributed to diarrhoea in 2008 and 49% of them occurring in five countries namely, India, Nigeria, Democratic Republic of the Congo, Pakistan and China, there is an urgent need for intervention to prevent and control diarrhoeal diseases. Of the various interventions, probiotics offer immense potential. The past decade has witnessed the validation of their utility for the prevention, treatment and management of a variety of infective and non infective disorders. The most investigated field continues to remain infectious diarrhoea and compelling evidence comes from randomized placebo controlled trials. While results from these studies are encouraging most of them reflect the outcomes of the developed world. Developing countries like India continue to struggle with nutritional and health challenges and bear the greatest burden of diarrhoea. A paucity of data from the developing countries limits the definite recommendation of probiotics. In these countries curd, often confused for a probiotic, is practiced as an integral part of the culture. While the nutritional benefits of these products cannot be understated, it is still uncertain whether these products can be classified as a probiotic. The emergence of probiotic foods which are scientifically validated for their efficacy and impart defined health benefits offer an excellent opportunity to improve public health. A recent randomized controlled trial conducted by the National Institute of Cholera and Enteric Diseases in Kolkata, India demonstrated a protective efficacy of 14% in preventing diarrhoea among children who received a probiotic. For the developing world however the vision for probiotics would mean a fundamental change in perception and developing a well planned strategy to allow interventions like probiotics to permeate to impoverished settings, where the assault of micro organisms is on a daily basis. This would mean that probiotics are ingrained into the public health system without being seen as a medicine.

Measurement issues in trials of pediatric acute diarrheal diseases: a systematic review

BACKGROUND

Worldwide, diarrheal diseases rank second among conditions that afflict children. Despite the disease burden, there is limited consensus on how to define and measure pediatric acute diarrhea in trials.

OBJECTIVES

In RCTs of children involving acute diarrhea as the primary outcome, we documented (1) how acute diarrhea and its resolution were defined, (2) all primary outcomes, (3) the psychometric properties of instruments used to measure acute diarrhea and (4) the methodologic quality of included trials, as reported.

METHODS

We searched CENTRAL, Embase, Global Health, and Medline from inception to February 2009. English-language RCTs of children younger than 19 years that measured acute diarrhea as a primary outcome were chosen.

RESULTS

We identified 138 RCTs reporting on 1 or more primary outcomes related to pediatric acute diarrhea/diseases. Included trials used 64 unique definitions of diarrhea, 69 unique definitions of diarrhea resolution, and 46 unique primary outcomes. The majority of included trials evaluated short-term clinical disease activity (incidence and duration of diarrhea), laboratory outcomes, or a composite of these end points. Thirty-two trials used instruments (eg, single and multidomain scoring systems) to support assessment of disease activity. Of these, 3 trials stated that their instrument was valid; however, none of the trials (or their citations) reported evidence of this validity. The overall methodologic quality of included trials was good.

CONCLUSIONS

Even in what would be considered methodologically sound clinical trials, definitions of diarrhea, primary outcomes, and instruments employed in RCTs of pediatric acute diarrhea are heterogeneous, lack evidence of validity, and focus on indices that may not be important to participants.

Health benefits of nut consumption

We investigated the effect of a mixture of long-chain fructo-oligosaccharides, galacto-oligosaccharides and acidic oligosaccharides on the number and consistency of stools and on immune system biomarkers in 104 supplemented and non-supplemented subjects (aged 9-24 months) with acute diarrhea. Interleukin-1 (IL-1), IL-1RA, IL-6, IL-8, IL-10, TNF-α and sIL-2R cytokine levels were determined. The significant decrease in number of stools and increase in stool consistency in the supplemented group was of little clinical relevance. The only significant change in pro- and anti-inflammatory cytokines was decreased TNF-α levels in the supplemented group. Prebiotic supplementation during acute diarrhea episodes did not influence the clinical course.

A randomized controlled trial to evaluate the efficacy of lactobacillus GG in infantile diarrhea

In a randomized, double-blind, placebo-controlled trial, 229 infants hospitalized for acute diarrhea in rural India were given a 10-day course of Lactobacillus rhammosus GG (minimum dose, 10 degrees bacteria) or placebo. There was no difference in groups in the duration of diarrhea or numbers of stool on days 3, 6, or 10 of treatment.

Targeting the human microbiome with antibiotics, probiotics, and prebiotics: gastroenterology enters the metagenomics era

Studies of metagenomics and the human microbiome will tremendously expand our knowledge of the composition of microbial communities in the human body. As our understanding of microbial variation and corresponding genetic parameters is refined, this information can be applied to rational remodeling or "tailoring" of human-associated microbial communities and their associated functions. Physiologic features such as the development of innate and adaptive immunity, relative susceptibilities to infections, immune tolerance, bioavailability of nutrients, and intestinal barrier function may be modified by changing the composition and functions of the microbial communities. The specialty of gastroenterology will be affected profoundly by the ability to modify the gastrointestinal microbiota through the rational deployment of antibiotics, probiotics, and prebiotics. Antibiotics might be used to remove or suppress undesirable components of the human microbiome. Probiotics can introduce missing microbial components with known beneficial functions for the human host. Prebiotics can enhance the proliferation of beneficial microbes or probiotics, to maximize sustainable changes in the human microbiome. Combinations of these approaches might provide synergistic and effective therapies for specific disorders. The human microbiome could be manipulated by such "smart" strategies to prevent and treat acute gastroenteritis, antibiotic-associated diarrhea and colitis, inflammatory bowel disease, irritable bowel syndrome, necrotizing enterocolitis, and a variety of other disorders.

Parental management of childhood diarrhea

The objective was to determine the prevalence of therapies used by parents to manage acute diarrhea in their children and determine extent of parental adherence to current management guidelines and utilization of functional foods. Parents (N=623) of children with diarrhea were surveyed in a tertiary care pediatric emergency department. Most (53%) treated their child's diarrhea with appropriate fluids, including oral rehydration solution (52%), but 14% used treatments not recommended in current guidelines (antidiarrheals, 8%; fluids high in simple sugars, 6%). In addition, 13% used functional foods (yogurt, 11%; probiotics, 4%). Children whose parents did not adhere to guidelines were older (OR 1.02; 95% CI 1.01-1.02 years) and Hispanic (OR 2.1; 95% CI 1.1-3.9). Although most parents use appropriate fluids to treat their children's diarrhea, functional foods and antidiarrheal medications were also frequently administered. Further data on effectiveness of functional foods and education regarding avoidance of potentially harmful medications are needed.

Assessment of the safety, tolerance, and protective effect against diarrhea of infant formulas containing mixtures of probiotics or probiotics and prebiotics in a randomized controlled trial

BACKGROUND

Probiotics and prebiotics are considered to be beneficial to the gastrointestinal health of infants.

OBJECTIVE

The objective was to evaluate infant formulas containing probiotics and synbiotics (combinations of probiotics and prebiotics) for safety and tolerance.

DESIGN

In a prospective, controlled, double-blind, randomized trial, healthy full-term infants were exclusively fed a control formula or study formulas containing Bifidobacterium longum BL999 (BL999) + Lactobacillus rhamnosus LPR (LPR), BL999 + LPR + 4 g/L of 90% galactooligosaccharide/10% short-chain fructooligosaccharide (GOS/SCFOS), or BL999 + Lactobacillus paracasei ST11 (ST11) + 4 g/L GOS/SCFOS from < or = 2 to 16 wk of age (treatment period). Safety and tolerance were assessed based on weight gain during the treatment period (primary outcome) as well as recumbent length, head circumference, digestive tolerance, and adverse events (secondary outcomes), which were evaluated at 2, 4, 8, 12, 16, and 52 wk of age.

RESULTS

Two hundred eighty-four infants were enrolled. During the treatment period, difference in mean weight gain between control and study formula groups in both the intention-to-treat and per-protocol populations were within the predefined equivalence boundaries of +/-3.9 g/d, indicating equivalent weight gain. Secondary outcomes did not show significant differences between groups during the treatment period.

CONCLUSION

Infants fed formulas containing probiotics or synbiotics show a similar rate in weight gain compared with those fed a control formula and tolerate these formulas well.

Probiotics in clinical practice: an overview

The observation that intestinal bacterial microflora might be able to influence immune system surveillance through changed nutritional habits has raised awareness of the role of probiotics. These are live microorganisms that are able to reach the gastrointestinal tract and alter its microfloral composition, producing beneficial health effects when consumed in adequate amounts. Recent clinical trials have evaluated the clinical effectiveness of probiotics in the treatment and prevention of a wide range of acute and chronic gastrointestinal diseases, and also non-gastrointestinal diseases, such as atopy, respiratory infections, vaginitis and hypercholesterolaemia. Probiotic supplements are generally regarded as safe because the microorganisms they contain are identical to those found in human gastrointestinal and vaginal microflora. Guidelines on the use of probiotics in the clinical setting require periodical updates for the latest data to be included in clinical applications. The purpose of this clinical report is to review current evidence on the use of probiotics in a variety of gastrointestinal and non-gastrointestinal conditions.

Probiotic modulation of symbiotic gut microbial-host metabolic interactions in a humanized microbiome mouse model

The transgenomic metabolic effects of exposure to either Lactobacillus paracasei or Lactobacillus rhamnosus probiotics have been measured and mapped in humanized extended genome mice (germ-free mice colonized with human baby flora). Statistical analysis of the compartmental fluctuations in diverse metabolic compartments, including biofluids, tissue and cecal short-chain fatty acids (SCFAs) in relation to microbial population modulation generated a novel top-down systems biology view of the host response to probiotic intervention. Probiotic exposure exerted microbiome modification and resulted in altered hepatic lipid metabolism coupled with lowered plasma lipoprotein levels and apparent stimulated glycolysis. Probiotic treatments also altered a diverse range of pathways outcomes, including amino-acid metabolism, methylamines and SCFAs. The novel application of hierarchical-principal component analysis allowed visualization of multicompartmental transgenomic metabolic interactions that could also be resolved at the compartment and pathway level. These integrated system investigations demonstrate the potential of metabolic profiling as a top-down systems biology driver for investigating the mechanistic basis of probiotic action and the therapeutic surveillance of the gut microbial activity related to dietary supplementation of probiotics.

Probiotics in children

The gastrointestinal flora plays a complex and important role in the development of healthy immunologic and digestive function in children. Probiotics are safe in healthy children and effective in reducing the risk of antibiotic-associated diarrhea and the duration of acute infectious diarrhea. Probiotics may also be effective in preventing community-acquired diarrheal infections, in reducing the risk of necrotizing enterocolitis in premature infants, and in the prevention and treatment of atopic dermatitis. The exact strain or combination of strains most effective for common clinical indications has yet to be determined, but the exact strain used seems less important than whether an adequate dose is used (typically 5 to 10 billion CFUs per day or higher). Clinicians should familiarize themselves with the products available because there is a wide range in their quality.

Probiotics in infectious diarrhoea in children: are they indicated?

Infectious gastroenteritis continues to be a leading cause of mortality and morbidity worldwide. The cornerstone of treatment remains replacement of water and electrolyte losses with oral rehydration solution. Until a few years ago, probiotics were discussed primarily in the context of alternative medicine, but they are now entering mainstream medical practice since a decrease of the severity and duration of infectious gastroenteritis in approximately 24 hours has been shown for some strains. Therefore, probiotics are a potential add-on therapy in acute gastro-enteritis. The shortening of the duration of diarrhoea and the reduction in hospital stay result in a social and economic benefit. Evidence found in viral gastroenteritis is more convincing than in bacterial or parasitic infection. Mechanisms of action are strain specific and only those commercial products for which there is evidence of clinical efficacy should be recommended. Timing of administration is also of importance. In acute gastroenteritis, there is evidence for efficacy of some strains of lactobacilli (e.g. Lactobacillus caseii GG and Lactobacillus reuteri) and for Saccharomyces boulardii. Probiotics are "generally regarded as safe", but side effects such as septicaemia and fungaemia have very rarely been reported in high-risk situations. Although most studies conclude in a statistically significant shortening of the duration of diarrhea, the clinical relevance of this finding is limited. In conclusion, selected strains of probiotics result in a statistically significant but clinically moderate benefit in shortening the duration of diarrhoea caused by acute infectious gastroenteritis.

Efficacy of Lactobacillus rhamnosus GG in acute watery diarrhoea of Indian children: a randomised controlled trial

AIM

To evaluate the role of Lactobacillus rhamnosus GG (LGG) as probiotic in acute watery diarrhoea (AWD).

SETTING

Hospital-based study.

DESIGN

Randomised, controlled, blinded trial.

PATIENTS AND METHOD

All patients of AWD (n = 684) admitted over 1-year period were invited to participate in the study as per predefined inclusion and exclusion criteria and were randomised to intervention and control groups. After adequate rehydration the intervention group (n = 330) received ORS with probiotic powder containing 60 million cells of LGG, while the control group (n = 332) received ORS alone twice daily for a minimum period of 7 days or till diarrhoea ceased. During the study period all patients received ORS and/or IV fluids for ongoing losses, and nutritional supplementation. None of them received any antibiotic or antidiarrhoeal medication. After exclusion of 16 patients, 646 (323 in each arm) patients completed the study. The daily frequency and total duration of diarrhoea and vomiting and the length of hospital stay were studied. Data were analysed by SPSS-10 software. Statistical significance was calculated by Student's t-test and chi2-test.

RESULTS

Rotavirus was isolated in 75.85%. There was no significant difference between treatment groups in the daily frequency or duration of diarrhoea or vomiting or in the length of hospital stay. No complication was observed from the use of LGG.

CONCLUSION

LGG supplementation does not decrease the frequency and duration of diarrhoea and vomiting in children with AWD, and does not reduce hospital stay in these patients.

Prevention and treatment of enteric viral infections: possible benefits of probiotic bacteria

The structure and function of the intestinal epithelium is briefly described, with the principal mechanisms involved in diarrhea. Human enteric viruses and probiotics are presented. We then review how probiotic bacteria could interfere with virus-induced pathology, we present our own view and describe specific interactions that would be valuable targets for future studies.

An experimental study and a randomized, double-blind, placebo-controlled clinical trial to evaluate the antisecretory activity of Lactobacillus acidophilus strain LB against nonrotavirus diarrhea

OBJECTIVE

Previous studies have shown that selected strains of Lactobacillus have the capacity to antagonize rotavirus-induced diarrhea. However, only a few reports have documented their efficacy against nonrotavirus diarrhea. This study involved an experimental investigation and a clinical trial of the antisecretory activity of Lactobacillus acidophilus strain LB in the context of nonrotavirus diarrhea.

METHODS

The activity of a culture of L. acidophilus LB or of the lyophilized, heat-killed L. acidophilus LB bacteria plus their spent culture medium was tested in inhibiting the formation of fluid-formed domes in cultured human intestinal Caco-2/TC7 cell monolayers infected with diarrheagenic, diffusely adhering Afa/Dr Escherichia coli C1845 bacteria. A randomized, double-blind, placebo-controlled clinical trial of male or female children who were 10 months of age and presented with nonrotavirus, well-established diarrhea was conducted to evaluate the therapeutic efficacy of a pharmaceutical preparation that contains 10 billion heat-killed L. acidophilus LB plus 160 mg of spent culture medium.

RESULTS

Infection of the cells with C1845 bacteria that were treated with L. acidophilus LB culture or the lyophilized, heat-killed L. acidophilus LB bacteria plus their culture medium produced a dosage-dependent decrease in the number of fluid-formed domes as compared with cells that were infected with untreated C1845 bacteria. The clinical results show that in selected and controlled homogeneous groups of children with well-established, nonrotavirus diarrhea, adding lyophilized, heat-killed L. acidophilus LB bacteria plus their culture medium to a solution of oral rehydration solution shortened by 1 day the recovery time (ie, the time until the first normal stool was passed) as compared with children who received placebo oral rehydration solution.

CONCLUSIONS

Heat-killed L. acidophilus LB plus its culture medium antagonizes the C1845-induced increase in paracellular permeability in intestinal Caco-2/TC7 cells and produces a clinically significant benefit in the management of children with nonrotavirus, well-established diarrhea.

Effective prophylaxis against rotavirus diarrhea using a combination of Lactobacillus rhamnosus GG and antibodies

Background

Rotavirus is a worldwide cause of infectious infantile diarrhea that claims over 600,000 lives annually. Recently, two new vaccine candidates have been developed but their efficacy in developing countries, still remains to be proven. Oral delivery of specific immunoglobulins provides passive immunity and is a fast acting treatment for rotavirus diarrhea. Probiotic bacteria have also gained considerable attention lately as treatment for rotavirus diarrhea. Here we report an evaluation of the therapeutic potential of different probiotics and their combination with anti – rotavirus antibodies in a mouse model of rotavirus diarrhea.

Results

Of the six probiotic bacteria tested, Lactobacillus rhamnosus strain GG had the strongest influence in reducing prevalence, duration and severity of diarrhea and was therefore chosen for combination treatment with immunoglobulins. The combination treatment reduced the diarrhea outcome measures significantly, prevented histopathological changes and reduced the virus load in the intestines.

Conclusion

The advantages associated with immunoglobulins and probiotics based therapy is that the treatment provides a rapid therapeutic effect and is cost efficient. These components do not require special storage conditions and could potentially complement the rehydration therapy that is currently used.

Acute infectious pediatric gastroenteritis: beyond oral rehydration therapy

Worldwide diarrheal diseases are a leading cause of childhood morbidity and mortality. Improvements in gastroenteritis management have reduced the annual number of pediatric deaths attributable to gastroenteritis from 5 million in 1982 to 2 million over 20 years. Recent advances are likely to contribute further to a reduction in morbidity and mortality secondary to acute infectious gastroenteritis. A new generation of vaccines against rotavirus is entering into routine use. Research into antisecretory agents has demonstrated that this class of medications may play a significant role in the future management of acute infectious gastroenteritis. A significant body of literature has recently emerged supporting the use of the antiemetic agent ondansetron. In developing countries, the routine use of zinc is now recommended by many experts, while, in developed countries, the use of probiotic agents has been associated with significant benefits in acute infectious gastroenteritis. Finally, more aggressive intravenous rehydration strategies are being employed; however, at present, limited data from randomized clinical trials are available to support its routine use.

Probiotics and zinc in acute infectious gastroenteritis in children: are they effective?

OBJECTIVE

Several studies in recent decades have assessed the effects of different probiotics in acute gastroenteritis, showing that specific strains of Lactobacilli (mainly Lactobacillus casei GG) and Saccharomyces boulardii may exert some beneficial therapeutic actions, mainly when used in rotavirus gastroenteritis, at a high dose, and in the early phase. The mechanisms of action of probiotics are not completely elucidated but seem to involve a complex interaction among epithelial, molecular, metabolic, and immune responses. Data on the prevention of community-acquired, nosocomial, and travelers' diarrhea are currently conflicting. Because each micro-organism has different properties, an accurate selection of the strain, dose, and patient should be cautiously considered.

METHODS AND RESULTS

Several reports from developing countries have demonstrated that supplements of zinc also provide significant reduction in stool output and duration, persistency, and severity of diarrhea. In view of the published data and of the different actions of zinc (such as improvement of the immune status, intestinal permeability, epithelial and enzymatic function, and electrolyte transport), the use of zinc as adjunctive therapy to oral rehydration solution has the potential to improve the management of diarrhea and decrease complications in children worldwide. In contrast to probiotics, which most trials in the developed world have used, there has been no trial with zinc performed in developed countries.

CONCLUSION

Data on the effect of a combined administration of zinc and probiotics in acute gastroenteritis are urgently needed.

Identification of commensal bacterial strains that modulate Yersinia enterocolitica and dextran sodium sulfate-induced inflammatory responses: implications for the development of probiotics

An increasing body of evidence suggests that probiotic bacteria are effective in the treatment of enteric infections, although the molecular basis of this activity remains elusive. To identify putative probiotics, we tested commensal bacteria in terms of their toxicity, invasiveness, inhibition of Yersinia-induced inflammation in vitro and in vivo, and modulation of dextran sodium sulfate (DSS)-induced colitis in mice. The commensal bacteria Escherichia coli, Bifidobacterium adolescentis, Bacteroides vulgatus, Bacteroides distasonis, and Streptococcus salivarius were screened for adhesion to, invasion of, and toxicity for host epithelial cells (EC), and the strains were tested for their ability to inhibit Y. enterocolitica-induced NF-kappaB activation. Additionally, B. adolescentis was administered to mice orally infected with Y. enterocolitica and to mice with mucosae impaired by DSS treatment. None of the commensal bacteria tested was toxic for or invaded the EC. B. adolescentis, B. distasonis, B. vulgatus, and S. salivarius inhibited the Y. enterocolitica-induced NF-kappaB activation and interleukin-8 production in EC. In line with these findings, B. adolescentis-fed mice had significantly lower results for mean pathogen burden in the visceral organs, intestinal tumor necrosis factor alpha mRNA expression, and loss of body weight upon oral infection with Y. enterocolitica. In addition, the administration of B. adolescentis decelerated inflammation upon DSS treatment in mice. We suggest that our approach might help to identify new probiotics to be used for the treatment of inflammatory and infectious gastrointestinal disorders.

Growth of probiotic bacteria and bifidobacteria in a soy yogurt formulation

Soy beverage and cows' milk yogurts were produced with Steptococcus thermophilus (ATCC 4356) and Lactobacillus delbrueckii subsp. bulgaricus (IM 025). The drop in pH during fermentation was faster in the soy beverage than in cows' milk, but the final pH values were similar. Yogurts were prepared with a yogurt starter in conjunction with either the probiotic bacteria Lactobacillus johnsonii NCC533 (La-1), Lactobacillus rhamnosus ATCC 53103 (GG) or human derived bifidobacteria. The presence of the probiotic bacteria did not affect the growth of the yogurt strains. Approximately 2 log increases in both L. rhamnosus GG and L. johnsonii La-1 were observed when each was added with the yogurt strains in both cows' milk and the soy beverage. Two of the five bifidobacteria strains grew well in the cows' milk and soy beverage during fermentation with the yogurt bacteria. High pressure liquid chromatography (HPLC) analyses showed that the probiotic bacteria and the bifidobacteria were using different sugars to support their growth, depending on whether the bacteria were growing in cows' milk or soy beverage.

Effects of probiotic Lactobacillus paracasei treatment on the host gut tissue metabolic profiles probed via magic-angle-spinning NMR spectroscopy

We have used a simplified gnotobiotic mouse model to evaluate the effects of single bacterial species, Lactobacillus paracasei NCC2461, on the metabolic profiles of intact intestinal tissues using high-resolution magic-angle-spinning 1H NMR spectroscopy (HRMAS). A total of 24 female gnotobiotic mice were divided into three groups: a control group supplemented with water and two groups supplemented with either live L. paracasei or a gamma-irradiated equivalent. HRMAS was used to characterize the biochemical components of intact epithelial tissues from the duodenum, jejunum, ileum, proximal, and distal colons in all animals and data were analyzed using chemometrics. Variations in relative concentrations of amino acids, anti-oxidant, and creatine were observed relating to different physiological properties in each intestinal tissue. Metabolic characteristics of lipogenesis and fat storage were observed in the jejunum and colon. Colonization with live L. paracasei induced region-dependent changes in the metabolic profiles of all intestinal tissues, except for the colon, consistent with modulation of intestinal digestion, absorption of nutrients, energy metabolism, lipid synthesis and protective functions. Ingestion of gamma-irradiated bacteria produced no effects on the observed metabolic profiles. 1H MAS NMR spectroscopy was able to generate characteristic metabolic signatures reflecting the structure and function of intestinal tissues. These signals acted as reference profiles with which to compare changes in response to gut microbiota manipulation at the tissue level as demonstrated by ingestion of a bacterial probiotic.

Similarity and differences in the Lactobacillus acidophilus group identified by polyphasic analysis and comparative genomics

A set of lactobacilli were investigated by polyphasic analysis. Multilocus sequence analysis, DNA typing, microarray analysis, and in silico whole-genome alignments provided a remarkably consistent pattern of similarity within the Lactobacillus acidophilus complex. On microarray analysis, 17 and 5% of the genes from Lactobacillus johnsonii strain NCC533 represented variable and strain-specific genes, respectively, when tested against four independent isolates of L. johnsonii. When projected on the NCC533 genome map, about 10 large clusters of variable genes were identified, and they were enriched around the terminus of replication. A quarter of the variable genes and two-thirds of the strain-specific genes were associated with mobile DNA. Signatures for horizontal gene transfer and modular evolution were found in prophages and in DNA from the exopolysaccharide biosynthesis cluster. On microarray hybridizations, Lactobacillus gasseri strains showed a shift to significantly lower fluorescence intensities than the L. johnsonii test strains, and only genes encoding very conserved cellular functions from L. acidophilus hybridized to the L. johnsonii array. In-silico comparative genomics showed extensive protein sequence similarity and genome synteny of L. johnsonii with L. gasseri, L. acidophilus, and Lactobacillus delbrueckii; moderate synteny with Lactobacillus casei; and scattered X-type sharing of protein sequence identity with the other sequenced lactobacilli. The observation of a stepwise decrease in similarity between the members of the L. acidophilus group suggests a strong element of vertical evolution in a natural phylogenetic group. Modern whole-genome-based techniques are thus a useful adjunct to the clarification of taxonomical relationships in problematic bacterial groups.

Probiotics as functional food in the treatment of diarrhea

PURPOSE OF REVIEW

A disturbance in microbial balance of the gastrointestinal tract is often associated with diarrhea. Therefore, probiotics, as beneficial microorganisms for host health, have attracted clinical attention for their potential therapeutic application in the treatment of diarrhea. This review focuses on new research findings relevant to the effects of probiotics on diarrhea prevention and treatment and potential mechanisms of action for this alternative therapy for diarrhea.

RECENT FINDINGS

Clinical trials suggest potential beneficial effects of probiotic therapy for preventing and treating antibiotic-associated diarrhea, acute diarrhea including rotavirus-induced diarrhea, traveler's diarrhea, and diarrhea-predominant irritable bowel syndrome. The most extensively studied probiotics for diarrhea are Lactobacillus, Bifidobacterium and Saccharomyces, with potential mechanisms of therapeutic action based on the protection of intestinal epithelial cell and barrier function, prevention of enterotoxin binding to intestinal epithelial cells, and regulation of intestinal microbial environment.

SUMMARY

Growing evidence suggests that probiotics may serve as a functional food in the treatment of diarrhea. Remaining challenges include identifying mechanisms of action to provide the basis of more refined hypothesis-driven clinical trials. The correct combination and concentration of probiotics applied to the appropriate gastrointestinal disorders may improve the efficacy of this approach for diarrhea and other diseases.

Clinical efficacy of probiotics: review of the evidence with focus on children

Probiotics are marketed in several countries and widely used by pediatric health care providers. Although probiotics can be helpful for specific disorders, they have been broadly prescribed for disorders without clear evidence to support their use. Furthermore, in certain specific conditions, probiotics cause clinical deterioration. This report is a review and evaluation of the evidence or lack thereof to support a beneficial effect of probiotic agents in a variety of pediatric conditions and to review the safety and potential adverse events that may be encountered when using probiotics. It is also important to emphasize that probiotics are highly heterogeneous with differences in composition, biological activity, and dose among the different probiotic preparations.

Effect of nitazoxanide for treatment of severe rotavirus diarrhoea: randomised double-blind placebo-controlled trial

BACKGROUND

Rotavirus is a leading cause of morbidity and mortality in children younger than 5 years, but there is no effective treatment. We assessed the activity of nitazoxanide, a broad-spectrum anti-infective drug, against rotavirus in cell culture and in a clinical trial in paediatric patients hospitalised with severe rotavirus diarrhoea.

METHODS

We did a randomised double-blind placebo-controlled trial in 50 children admitted to the Cairo University Children's Hospital between June 15 and Aug 23, 2005, with severe rotavirus diarrhoea. 38 children aged 5 months to 7 years (median age 11 months) with rotavirus as the sole identified cause of gastroenteritis were enrolled in the clinical study. Patients were randomly assigned either 7.5 mg/kg nitazoxanide as an oral suspension or placebo twice a day for 3 days, and all remained in hospital for 7 days after start of treatment. The primary endpoint was time from first dose to resolution of illness, and analysis was by modified intention-to-treat. This study is registered with ClinicalTrials.gov, number NCT00302640.

FINDINGS

Survival analysis showed that the median time to resolution of illness was 31 h (IQR 22-73) for the nitazoxanide-treated group compared with 75 h (51-124) for the placebo group (p=0.0137). No significant adverse events were reported.

INTERPRETATION

A 3-day course of nitazoxanide significantly reduced the duration of rotavirus disease in hospitalised paediatric patients. These results are encouraging, and might lead us to think about new approaches to managing rotavirus disease in children.

Probiotics in gastrointestinal diseases in children: hard and not-so-hard evidence of efficacy

The use of probiotics, once discussed primarily in the context of alternative medicine, is now entering mainstream medicine. However, only a few of the potential health benefits attributed to probiotics have been confirmed in well-designed, well-conducted, randomized, controlled trials. This is especially true in the pediatric population. We review here the available evidence on efficacy of probiotics in children in the prevention and treatment of gastrointestinal diseases. Although we restrict our analysis to the pediatric age, whenever potentially relevant information is available only from adult studies, they are examined as well. Probiotics have been most extensively studied in the treatment of diarrheal diseases, where their efficacy can be considered well established. Studies documenting effects in other childhood gastrointestinal illnesses are few, although some preliminary results are promising. Furthermore, only a limited number of probiotic strains have been tested, and, as the effects of different probiotic microorganisms are not equivalent, results cannot be generalized. Thus, at present, we have some positive certainties, lots of exciting promises and many unanswered questions.

Correlation of probioticLactobacillus salivariusgrowth phase with its cell wall-associated proteome

Lactobacillus salivarius subsp. salivarius UCC118 is a probiotic bacterium that was originally isolated from human intestinal tissues and was subsequently shown in a pilot study to alleviate symptoms associated with mild-moderate Crohn's disease. Strain UCC118 can adhere to animal and human intestinal tissue, and to both healthy and inflamed ulcerative colitis mucosa, irrespective of location in the gut. In this study, an enzymatic technique has been combined with proteomic analysis to correlate bacterial growth phase with the presence of factors present in the cell wall of the bacterium. Using PAGE electrophoresis, it was determined that progression from lag to log to stationary growth phases in vitro correlated with increasing prominence of an 84kD protein associated with in vitro adherence ability. Isolated proteins from the 84kD band region were further separated by two-dimensional electrophoresis, resolving this band into 20 individual protein spots at differing isoelectric points. The protein moieties were excised, trypsin digested and subjected to tandem mass spectrometry. The observed proteins are analogous to those reported to be associated with the Listeria monocytogenes cell-wall proteome, and include DnaK, Ef-Ts and pyruvate kinase. These data suggest that at least some of the beneficial attributes of probiotic lactobacilli, and in particular this strain, may be due to nonpathogenic mimicry of pathogens and potentially be mediated through a form of attenuated virulence.