An update on the use and investigation of probiotics in health and disease

Chemoprevention by Probiotics During 1,2-Dimethylhydrazine-Induced Colon Carcinogenesis in Rats

BACKGROUND

Probiotics are believed to have properties that lower the risk of colon cancer. However, the mechanisms by which they exert their beneficial effects are relatively unknown.

AIM

To assess the impact of probiotics in preventing induction of colon carcinogenesis in rats.

METHODS

The rats were divided into six groups viz., normal control, Lactobacillus plantarum (AdF10)-treated, Lactobacillus rhamnosus GG (LGG)-treated, 1,2-dimethylhydrazine (DMH)-treated, L. plantarum (AdF10) + DMH-treated and L. rhamnosus GG (LGG) + DMH-treated. Both the probiotics were supplemented daily at a dose of 2 × 10¹⁰ cells per day. DMH at a dose of 30 mg/kg body weight was administered subcutaneously twice a week for the first 4 weeks and then once every week for a duration of 16 weeks. Glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and catalase as protein expression of genes involved in apoptosis were assessed during DMH-induced colon carcinogenesis in rats.

RESULTS

DMH treatment decreased the activity of GSH, GPx, GST, SOD and catalase. However, AdF10 and LGG supplementation to DMH-treated rats significantly increased the activity of these enzymes. Further, DMH treatment revealed alterations in the protein expressions of various genes involved in the p53-mediated apoptotic pathway such as p53, p21, Bcl-2, Bax, caspase-9 and caspase-3, which, however, were shifted towards normal control levels upon simultaneous supplementation with probiotics.

CONCLUSION

The present study suggests that probiotics can provide protection against oxidative stress and apoptotic-related protein disregulation during experimentally induced colon carcinogenesis.

Whether viable and dead probiotic are equally efficacious?

Purpose

Consumer inclination towards probiotic foods has been stimulated due to well-documented evidence of health benefits of probiotic-containing products and consumer demand for natural products. It is assumed that the viability and metabolic activities of probiotics are essential for extending health benefits and for successful marketing of probiotics as a functional food. The purpose of this paper is to demonstrate that even dead or inactivated probiotic cells could extend health benefits, indicating that probiotic viability is not always necessary for exhibiting health benefits.

Design/methodology/approach

Attempt has been made to review the literature on the status of probiotic foods available in the world market, their impact on the gut flora and the various factors affecting their viability. Both review and research papers related to efficacy of inactivated, killed or dead probiotic cells towards health benefits have been considered. Keywords used for data search included efficacy of viable or killed, inactivated probiotic cells.

Findings

The reviewed literature indicated that inactivated, killed or dead probiotic cells also possess functional properties but live cells are more efficacious. All live probiotic cultures are not equally efficacious, and accordingly, dead or inactivated cells did not demonstrate functional properties to extend health benefits to all diseases.

Originality/value

Capability of non-viable microorganisms to confer health benefits may attract food manufacturers owing to certain advantages over live probiotics such as longer shelf-life, handling and transportation and reduced requirements for refrigerated storage and inclusion of non-bacterial, biologically active metabolites present in fermented milks’ fraction as dried powders to food matrixes may result in the development of new functional foods.

Novel probiotics isolated from a Japanese traditional fermented food, Funazushi, attenuates DSS-induced colitis by increasing the induction of high integrin αv/β8-expressing dendritic cells

BACKGROUND

We isolated two novel probiotics strains (s193 and s292) from Funazushi, which is a traditional Japanese fermented food, and evaluated its effects on DSS-induced colitis to determine the possible underlying mechanisms.

METHODS

A single colony from homogenized Funazushi was isolated by its ability to suppress TNF-α in RAW 264.7. Effect of probiotics on colonic inflammation induced by DSS was evaluated. Effect of probiotics on Treg induction by CD11c⁺ dendritic cells (DCs) of MLNs were analyzed.

RESULTS

Two novel probiotics strains classified into the genus Lactobacillus were isolated (s193 and s292), and those strains showed stronger anti-inflammatory effects on DSS-induced colitis than those of L. gasseri isolated from the gut. mRNA expression β8 integrin in CD11c⁺DCs of MLNs and the number of Tregs in the large intestine were significantly increased by s193 and s292 administration compared with L. gasseri administration. Bone marrow DCs treated with s193 and s292 highly increased β8 integrin, and those cells strongly induced differentiation of CD4⁺ T cells into Tregs. Differentiation of Tregs was remarkably inhibited by anti-β8 integrin antibody treatment.

CONCLUSIONS

Strains s193 and s292 demonstrate strong anti-inflammatory effects on DSS-induced colitis through induction of β8 integrin expression on DCs. Our results suggested that Japanese traditional fermented foods are valuable sources for probiotics that are effective for IBD therapy and treatment.

Targeting gut microbiota in hepatocellular carcinoma: probiotics as a novel therapy

Hepatocellular carcinoma (HCC), the most common primary liver cancer, is one of the dreaded complications of chronic liver disease. Recent experimental and clinical studies have revealed that the alteration of gut-liver axis plays a pivotal role in the onset of chronic liver diseases, including HCC. Altered gut microbiota and endotoxemia are increasingly recognized as critical components in promoting the progression of chronic liver diseases to HCC. Probiotics have been suggested as a novel, safe and cost-effective approach to prevent or treat HCC. Mechanisms by which probiotics exerts their anti-cancer effects include their ability to bind carcinogens, modulation of gut microbiota, improvement of intestinal barrier function, and immunomodulation. This review summarizes the literature findings of the changes in gut microbiota linked to HCC, and discusses the possible therapeutic implications of probiotics for HCC.

The Role of Bacteria, Probiotics and Diet in Irritable Bowel Syndrome

Irritable bowel syndrome is a highly prevalent gastrointestinal disorder that threatens the quality of life of millions and poses a substantial financial burden on healthcare systems around the world. Intense research into the human microbiome has led to fascinating discoveries which directly and indirectly implicate the diversity and function of this occult organ in irritable bowel syndrome (IBS) pathophysiology. The benefit of manipulating the gastrointestinal microbiota with diet and probiotics to improve symptoms has been demonstrated in a wealth of both animal and human studies. The positive and negative mechanistic roles bacteria play in IBS will be explored and practical probiotic and dietary choices offered.

Involvement of gut microbiome in human health and disease: brief overview, knowledge gaps and research opportunities

The commensal, symbiotic, and pathogenic microbial community which resides inside our body and on our skin (the human microbiome) can perturb host energy metabolism and immunity, and thus significantly influence development of a variety of human diseases. Therefore, the field has attracted unprecedented attention in the last decade. Although a large amount of data has been generated, there are still many unanswered questions and no universal agreements on how microbiome affects human health have been agreed upon. Consequently, this review was written to provide an updated overview of the rapidly expanding field, with a focus on revealing knowledge gaps and research opportunities. Specifically, the review covered animal physiology, optimal microbiome standard, health intervention by manipulating microbiome, knowledge base building by text mining, microbiota community structure and its implications in human diseases and health monitoring by analyzing microbiome in the blood. The review should enhance interest in conducting novel microbiota investigations that will further improve health and therapy.

Effects of Bacillus coagulans supplementation on the growth performance and gut health of broiler chickens with Clostridium perfringens-induced necrotic enteritis

Background

The poultry industry is in need of effective antibiotic alternatives to control outbreaks of necrotic enteritis (NE) due to Clostridium perfringens.

Methods

This study was conducted to investigate the effects of feeding Bacillus coagulans on the growth performance and gut health of broiler chickens with C. perfringens-induced NE. Two hundred and forty 1-day-old broiler chicks were randomly assigned to a 2 × 2 factorial arrangement with two dietary B. coagulans levels (0 or 4 × 10⁹ CFU/kg of diet) and two disease challenge statuses (control or NE challenged).

Results

NE-induced reduction in body weight gain was relieved by the addition of B. coagulans into broiler diets compared with the NE-infected birds. NE infection damaged intestinal morphological structure, promoted intestinal C. perfringens growth and liver invasion, and enhanced anti-C. perfringens specific sIgA concentrations in the gut and specific IgG levels in serum compared with the uninfected birds. NE infection significantly (P < 0.05) decreased mucin-2 (at 14 d post-infection (DPI), toll -like receptor 2 (TLR2, at 7 and 14 DPI), TLR4 (at 7 and 14 DPI), tumor necrosis factor super family 15 (TNFSF15, at 7 and 14 DPI), lysozyme (LYZ, at 14 DPI) and fowlicidin-2 (at 7 and 14 DPI) mRNA levels, whereas it dramatically (P = 0.001) increased IFN-γ mRNA levels at 7 DPI. However, challenged birds fed diets supplemented with B. coagulans showed a significant (P < 0.01) decrease in gut lesion scores, decreased C. perfringens numbers in the cecum and liver, and an increase in fowlicidin-2 mRNA levels in compared with the uninfected birds. In addition, compared with the non-supplemented group, dietary inclusion of B. coagulans improved intestinal barrier structure, further increased specific sIgA levels and alkaline phosphatase (IAP) activity in the jejunum, enhanced the expression of jejunum lysozyme mRNA, and inhibited the growth, colonization, and invasion of C. perfringens; in contrast, it reduced serum-specific IgG concentrations and jejunum IFN-γ mRNA levels.

Conclusion

These results indicated that dietary B. coagulans supplementation appeared to be effective in preventing the occurrence and reducing the severity of C. perfringens-induced NE in broiler chickens.

Probiotics and their role in gastrointestinal cancers prevention and treatment; an overview

Cancers of the gastrointestinal (GI) track are a serious global health problem. The human GI tract is home to trillions of microorganisms that known as gut microbiota and have established a symbiotic relationship with the host. The human intestinal microbiota plays an important role in the development of the gut immune system, metabolism, nutrition absorption, production of short-chain fatty acids and essential vitamins, resistance to pathogenic microorganisms, and modulates a normal immunological response. Microbiota imbalance has been involved in many disorders including inflammatory bowel disease, obesity, asthma, psychiatric illnesses, and cancers. Oral administration of probiotics seems to play a protective role against cancer development as a kind of functional foods. Moreover, clinical application of probiotics has shown that some probiotic strains can reduce the incidence of post-operative inflammation in cancer patients. In the present narrative review, we carried out update knowledge on probiotic effects and underlying mechanism to GI cancers. Currently, it is accept that most commercial probiotic products are generally safe and can used as a supplement for cancer prevention and treatment. Nevertheless, well-designed, randomized, double blind, placebo-controlled human studies are required to gain the acceptance of the potential probiotics as an alternative therapy for cancer control..

Inhibition effect of Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus thermophilus and Enterococcus faecalis and their related products on human colonic smooth muscle in vitro

OBJECTIVE

To investigate the effects of four strains, generally used in clinic, including Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus thermophilus and Enterococcus faecalis, and their related products on human colonic smooth muscle in vitro.

METHODS

Human colonic circular muscle strips obtained from disease-free margins of resected segments from 25 patients with colorectal cancer were isometrically examined in a constant-temperature organ bath and exposed to different concentrations of living bacteria, sonicated cell fractions and cell-free supernatant (CFS). The area under the curve (AUC) representing the contractility of smooth muscle strips was calculated.

RESULTS

(1) The four living probiotics inhibited the contractility of human colonic muscle strips only at high concentration (1010 CFUs/mL, all P<0.05). (2) The sonicated cell fractions from the four probiotics obviously inhibited human colonic smooth muscle strips in a dose-dependent manner (P<0.01). (3) The CFS from the four probiotics also inhibited colonic smooth muscle strips in a dose-dependent manner (all P<0.05). (4) The inhibition effect of CFS from Streptococcus thermophilus and Enterococcus faecalis decreased obviously when pretreated with NG-nitro-L-arginine (L-NNA, 10-5 mol/L) (P<0.05), but not the Bifidobacterium longum and Lactobacillus acidophilus (P>0.05).

CONCLUSION

Four common probiotics related products, including the sonicated cell fractions and the CFS, obviously inhibited human colonic smooth muscles strips contraction in a dose-dependent manner. Only high concentration living probiotics (1010 CFUs/mL) can inhibit the colonic smooth muscles strips contraction. The NO pathway may be partly involved in the inhibitory effect of CFS from Streptococcus thermophilus and Enterococcus faecalis.

Neurobehavioural effects of Lactobacillus rhamnosus GG alone and in combination with prebiotics polydextrose and galactooligosaccharide in male rats exposed to early-life stress

Early life is a period of significant brain development when the brain is at its most plastic and vulnerable. Stressful episodes during this window of development have long-lasting effects on the central nervous system. Rodent maternal separation (MS) is a reliable model of early-life stress and induces alterations in both physiology and behaviour. Intriguingly, the gut microbiota of MS offspring differ from that of non-separated offspring, suggesting a mechanistic role for the microbiota-gut-brain axis. Hence, we tested whether dietary factors known to affect the gut microbiota alter the neurobehavioural effects of MS. The impact of consuming diet containing prebiotics polydextrose (PDX) and galactooligosaccharide (GOS) alone or in combination with live bacteria Lactobacillus rhamnosus GG (LGG) from weaning onwards in rats subjected to early-life MS was assessed. Adult offspring were assessed for anxiety-like behaviour in the open field test, spatial memory using the Morris water maze, and reactivity to restraint stress. Brains were examined via PCR for changes in mRNA gene expression. Here, we demonstrate that diets containing a combination of PDX/GOS and LGG attenuates the effects of early-life MS on anxiety-like behaviour and hippocampal-dependent learning with changes to hippocampal mRNA expression of genes related to stress circuitry, anxiety and learning.

The positive benefit of Lactobacillus paracasei NCC2461 ST11 in healthy volunteers with moderate to severe dandruff

Dandruff is a common persistent, relapsing inflammatory condition affecting the scalp. An imbalanced proportion of the major bacterial and fungal populations colonising the scalp, a skin barrier dysfunction, and hyperseborrhoea are three main etiological factors of dandruff. The efficacy of Lactobacillus paracasei NCC 2461 ST11 (ST11) to manage dandruff and to restore a balanced scalp microbiome was assessed. Sixty healthy male volunteers aged 18 to 60 years with moderate to severe dandruff consumed on a daily basis a sachet containing ST11 (1×109 cfu) or a placebo for 56 days. Clinical efficacy (free and adherent dandruff, erythema, scalp seborrhoea, global clinical score), subject self-assessments, safety reporting as well as scalp microbiota assessments were performed every two weeks (day 1, 15, 29, 43, 57 and 64/follow-up). Free and adherent dandruff, erythema and the global clinical score improved significantly (all P<0.05) over time in the ST11 group and as compared to the placebo when day 57 was compared to day 1. Self-assessments paralleled these findings. ST11 enhanced restoring the scalp microbiota after 56 days of supplementation when compared to the placebo. No adverse events were reported. Regular intake of ST11 over 56 days is safe and reduces significantly the severity of signs and symptoms of moderate to severe dandruff. Its efficacy is potentially due to its positive impact on the skin barrier and skin immune system.

Influence of Acute Multispecies and Multistrain Probiotic Supplementation on Cardiovascular Function and Reactivity to Psychological Stress in Young Adults: A Double-Blind, Randomized, Placebo-Controlled Trial

OBJECTIVE

The potential influence of probiotic supplementation on cardiovascular health and stress responsivity remains largely unexplored. Some evidence suggests the possibility that probiotics may influence blood pressure. A separate body of research suggests that exaggerated cardiovascular reactions to acute psychological stress in the laboratory predict cardiovascular morbidity and mortality. The current investigation explored the effect of acute probiotic use on (1) resting cardiovascular measures in healthy young adults and (2) cardiovascular and psychological reactions to an acute psychological stressor in the laboratory.

METHOD

Participants (N = 105, M [SD] age = 20.17 [1.26], 84.8% white) completed a 2-week, double-blind, and placebo-controlled trial of a multispecies and multistrain probiotic. Exclusion criteria included previous probiotic use, diagnosed gastrointestinal disorder, and/or current antibiotic use. At visits 1 and 2, participants completed the Paced Auditory Serial Addition Test, a widely used psychological stress task. Participants were randomly assigned to a probiotic blend or matched placebo.

RESULTS

Compared with placebo, 2-week probiotic supplementation did not affect resting measures of cardiovascular function, cardiovascular responses during or recovery from stress, or psychological reactions to acute psychological stress.

CONCLUSIONS

Contrary to expectations, short-term use of a probiotic supplement in healthy participants did not influence measures of cardiovascular function or responsivity to psychological stress. Future research is needed to determine species- and strain-specific effects of probiotics in healthy participants with various degrees of stress responsiveness, as well as in diseased populations.

Gut microbiota and IBD: causation or correlation?

A general consensus exists that IBD is associated with compositional and metabolic changes in the intestinal microbiota (dysbiosis). However, a direct causal relationship between dysbiosis and IBD has not been definitively established in humans. Findings from animal models have revealed diverse and context-specific roles of the gut microbiota in health and disease, ranging from protective to pro-inflammatory actions. Moreover, evidence from these experimental models suggest that although gut bacteria often drive immune activation, chronic inflammation in turn shapes the gut microbiota and contributes to dysbiosis. The purpose of this Review is to summarize current associations between IBD and dysbiosis, describe the role of the gut microbiota in the context of specific animal models of colitis, and discuss the potential role of microbiota-focused interventions in the treatment of human IBD. Ultimately, more studies will be needed to define host-microbial relationships relevant to human disease and amenable to therapeutic interventions.

Methanobrevibacter attenuation via probiotic intervention reduces flatulence in adult human: A non-randomised paired-design clinical trial of efficacy

TRIAL DESIGN

The aim of this study was to investigate which of the gut microbes respond to probiotic intervention, as well as study whether they are associated with gastrointestinal symptoms in a healthy adult human. For the experimental purpose, twenty-one healthy adults were recruited and received probiotic mixture, which is composed of five Lactobacilli strains and two Bifidobacteria strains, once a day for 60 days. Defecation survey and Bioelectrical Impedance Analysis were conducted pre- and post-administration to measure phenotypic differences. Stool samples of the subjects were collected twice.

METHODS

The statistical analysis was performed for pair designed metagenome data with 11 phenotypic records of the bioelectrical impedance body composition analyzer and 6 responses of the questionnaires about gastrointestinal symptom. Furthemore, correlation-based network analysis was conducted for exploring complex relationships among microbiome communities.

RESULTS

The abundances of Citrobacter, Klebsiella, and Methanobrevibacter were significantly reduced, which are strong candidates to be highly affected by the probiotic administration. In addition, interaction effects were observed between flatulence symptom attenuation and decreasing patterns of the Methanobrevibacter abundance.

CONCLUSIONS

These results reveal that probiotic intervention modulated the composition of gut microbiota and reduced the abundance of potential pathogens (i.e. Citrobacter and Klebsiella). In addition, methanogens (i.e. Methanobrevibacter) associated with the gastrointestinal symptom in an adult human.

Persistent Luminescence Nanophosphor Involved Near-Infrared Optical Bioimaging for Investigation of Foodborne Probiotics Biodistribution in Vivo: A Proof-of-Concept Study

Probiotics has attracted great attention in food nutrition and safety research field, but thus far there are limited analytical techniques for visualized and real-time monitoring of the probiotics when they are ingested in vivo. Herein, the optical bioimaging technique has been introduced for investigation of foodborne probiotics biodistribution in vivo, employing the near-infrared (NIR) emitting persistent luminescence nanophosphors (PLNPs) of Cr³⁺-doped zinc gallogermanate (ZGGO) as the contrast nanoprobes. The ultrabrightness, super long afterglow, polydispersed size, low toxicity, and excellent photostability and biocompatibility of PLNPs were demonstrated to be qualified as a tracer for labeling probiotics via antibody (anti-Gram positive bacteria LTA antibody) recognition as well as contrast agent for long-term bioimaging the probiotics. In vivo optical bioimaging assay showed that the LTA antibody functionalized ZGGO nanoprobes that could be efficiently tagged to the probiobics were successfully applied for real-time monitoring and nondamaged probing of the biodistribution of probiotics inside the living body after oral administration. This work presents a proof-of-concept that exploited the bioimaging methodology for real-time and nondamaged researching the foodborne probiotics behaviors in vivo, which would open up a novel way of food safety detection and nutrition investigation.

Influence of indigenous microbiota on experimental toxoplasmosis in conventional and germ-free mice

Toxoplasmosis represents one of the most common zoonoses worldwide. Its agent, Toxoplasma gondii, causes a severe innate pro-inflammatory response. The indigenous intestinal microbiota promotes host animal homoeostasis and may protect the host against pathogens. Germ-free (GF) animals provide an important tool for the study of interactions between host and microbiota. In this study, we assessed the role of indigenous microorganisms in disease development utilizing a murine toxoplasmosis model, which includes conventional (CV) and GF NIH Swiss mice. CV and GF mice orally inoculated with T. gondii had similar survival curves. However, disease developed differently in the two animal groups. In CV mice, intestinal permeability increased and levels of intestinal pro-inflammatory cytokines were altered. In GF animals, there were discrete epithelial degenerative changes and mucosal oedema, but the liver and lungs displayed significant lesions. We conclude that, despite similar survival curves, CV animals succumb to an exaggerated inflammatory response, whereas GF mice fail to produce an adequate systemic response.

Extracts from Hericium erinaceus relieve inflammatory bowel disease by regulating immunity and gut microbiota

Hericium erinaceus (HE), a traditional edible mushroom, is known as a medicine food homology to ameliorate gastrointestinal diseases. To investigate whether HE is clinically effective in alleviating inflammatory bowel disease (IBD), HE extracts (polysaccharide, alcoholic extracts and whole extracts were prepared using solvent extraction methods) were administrated for 2 weeks in rats with IBD induced by trinitro-benzene-sulfonic acid (TNBS) enema (150 mg/kg). Significant clinical and histological changes in IBD rats were identified, including damage activity, common morphous and tissue damage index scores in colonic mucosa and myeloperoxidase (MPO) activity. The damage activity, common morphous and tissue damage index scores in colonic mucosa (P <0.05) were improved, MPO activities were decreased. Inflammatory factors were also differentially expressed in colonic mucosa in IBD rats, including serum cytokines, Foxp3 and interleukin (IL)-10 were increased while NF-κB p65 and tumor necrosis factor (TNF)-α were decreased (P <0.05), and T cells were activated (P <0.05), especially in the alcohol extracts-treated group. We also found that the structure of gut microbiota of the H. erinaceus extracts-treated groups changed significantly by compared with the model group. Further studies revealed that the polysaccharides in HE extracts may play a prebiotic role, whereas the alcoholic extracts show bactericidin-like and immunomodulatory effects. Taken together, we demonstrated that H. erinaceus extracts could promote the growth of beneficial gut bacteria and improve the host immunity in vivo IBD model, which shows clinical potential in relieving IBD by regulating gut microbiota and immune system.

Transmission of the gut microbiota: spreading of health

Transmission of commensal intestinal bacteria between humans could promote health by establishing, maintaining and replenishing microbial diversity in the microbiota of an individual. Unlike pathogens, the routes of transmission for commensal bacteria remain unappreciated and poorly understood, despite the likely commonalities between both. Consequently, broad infection control measures that are designed to prevent pathogen transmission and infection, such as oversanitation and the overuse of antibiotics, may inadvertently affect human health by altering normal commensal transmission. In this Review, we discuss the mechanisms and factors that influence host-to-host transmission of the intestinal microbiota and examine how a better understanding of these processes will identify new approaches to nurture and restore transmission routes that are used by beneficial bacteria.

Can probiotics enhance vaccine-specific immunity in children and adults?

The growing use of probiotics by the general public has heightened the interest in understanding the role of probiotics in promoting health and preventing disease. General practitioners and specialists often receive inquiries from their patients regarding probiotic products and their use to ward off systemic infection or intestinal maladies. Enhanced immune function is among the touted health benefits conferred by probiotics but has not yet been fully established. Results from recent clinical trials in adults suggest a potential role for probiotics in enhancing vaccine-specific immunity. Although almost all vaccinations are given during infancy and childhood, the numbers of and results from studies using probiotics in pediatric subjects are limited. This review evaluates recent clinical trials of probiotics used to enhance vaccine-specific immune responses in adults and infants. We highlight meaningful results and the implications of these findings for designing translational and clinical studies that will evaluate the potential clinical role for probiotics. We conclude that the touted health claims of probiotics for use in children to augment immunity warrant further investigation. In order to achieve this goal, a consensus should be reached on common study designs that apply similar treatment timelines, compare well-characterised probiotic strains and monitor effective responses against different classes of vaccines.

Streptococcus thermophilus NCIMB 41856 ameliorates signs of colitis in an animal model of inflammatory bowel disease

Treatment of inflammatory bowel disease (IBD) is mainly based on suppression of symptoms, often with numerous side effects. Trials of probiotics in IBD have frequently produced disappointing results. The majority of probiotics are unusual, since they do not require iron for growth, unlike many bacteria resident in the intestine. The IBD intestine is iron-rich due to bleeding and use of oral iron supplements; conventional probiotics would be rapidly outcompeted. We have evaluated an iron-responsive Streptococcus thermophilus strain for its potential to reduce signs of colitis. Efficacy of S. thermophilus was evaluated in the dextran sodium sulphate mouse model of colitis. Treated animals were given 1×108 cfu S. thermophilus per day and clinical observations were taken daily. At termination, gross and histopathological signs of disease, cellular infiltration, location of bacteria, and cytokine expression in the intestine were determined. S. thermophilus delayed onset of colitis and reduced clinical signs of disease, including bodyweight loss and gastrointestinal bleeding. It reduced bacterial translocation into the colonic tissue. Increased numbers of CD8+ intraepithelial lymphocytes were seen in control animals treated with S. thermophilus. S. thermophilus had no effect on gross pathology, histopathology or cytokine production in either colitic or control animals. We propose that S. thermophilus promotes maintenance of mucosal barrier function which reduces bacterial translocation, thereby reducing immune stimulation and associated inflammation. This allows mucosal healing, reducing gastrointestinal bleeding and weight loss. This could be studied as a locally-acting adjunct or alternative to current IBD treatments.

Probiotics Prevent Late-Onset Sepsis in Human Milk-Fed, Very Low Birth Weight Preterm Infants: Systematic Review and Meta-Analysis

Growing evidence supports the role of probiotics in reducing the risk of necrotizing enterocolitis, time to achieve full enteral feeding, and late-onset sepsis (LOS) in preterm infants. As reported for several neonatal clinical outcomes, recent data have suggested that nutrition might affect probiotics' efficacy. Nevertheless, the currently available literature does not explore the relationship between LOS prevention and type of feeding in preterm infants receiving probiotics. Thus, the aim of this systematic review and meta-analysis was to evaluate the effect of probiotics for LOS prevention in preterm infants according to type of feeding (exclusive human milk (HM) vs. exclusive formula or mixed feeding). Randomized-controlled trials involving preterm infants receiving probiotics and reporting on LOS were included in the systematic review. Only trials reporting on outcome according to feeding type were included in the meta-analysis. Fixed-effects models were used and random-effects models were used when significant heterogeneity was found. The results were expressed as risk ratio (RR) with 95% confidence interval (CI). Twenty-five studies were included in the meta-analysis. Overall, probiotic supplementation resulted in a significantly lower incidence of LOS (RR 0.79 (95% CI 0.71-0.88), p < 0.0001). According to feeding type, the beneficial effect of probiotics was confirmed only in exclusively HM-fed preterm infants (RR 0.75 (95% CI 0.65-0.86), p < 0.0001). Among HM-fed infants, only probiotic mixtures, and not single-strain products, were effective in reducing LOS incidence (RR 0.68 (95% CI 0.57-0.80) p < 0.00001). The results of the present meta-analysis show that probiotics reduce LOS incidence in exclusively HM-fed preterm infants. Further efforts are required to clarify the relationship between probiotics supplementation, HM, and feeding practices in preterm infants.

Probiotics-mediated suppression of cancer

PURPOSE OF REVIEW

Probiotics can be used as an adjuvant for cancer prevention or/and treatment through their abilities to modulate intestinal microbiota and host immune response. Although most of the recent reviews have focused on the potential role of probiotics against colon cancer, only few of them include the probiotic effect on extraintestinal cancers. The present review covers the most important findings from the literature published during the past 20 months (from January 2015 to August 2016) regarding the probiotics-mediated suppression of both gastrointestinal and extraintestinal cancers and the underlying mechanisms.

RECENT FINDINGS

A comprehensive literature search in Pubmed, Science direct and Google scholar databases was conducted to locate all relevant articles that investigated the effect of probiotics on prevention/treatment of both gastrointestinal and extraintestinal cancers. Different mechanisms for the beneficial effects of probiotics against cancer were also discussed, mainly via modulation of gut microbiota which thereby influences host metabolism and immunity.

SUMMARY

Despite laboratory-based studies having demonstrated encouraging outcomes that probiotics possess antitumor effects, the benefits should not be exaggerated before we get more results from human clinical trials. These are very important before the medical community can accept the use of probiotics as an alternative therapy for cancer control.

Anti-influenza Activity of a Bacillus subtilis Probiotic Strain

Among Bacillus bacteria, B. subtilis is the species that produces the most antimicrobial compounds. In this study, we analyzed the activity of probiotic strain B. subtilis 3 against the influenza virus. The antiviral effect of this strain has been demonstrated in vitro and in vivo A new peptide, P18, produced by the probiotic strain was isolated, purified, chemically synthesized, and characterized. Cytotoxicity studies demonstrated no toxic effect of P18 on Madin-Darby canine kidney (MDCK) cells, even at the highest concentration tested (100 μg/ml). Complete inhibition of the influenza virus in vitro was observed at concentrations of 12.5 to 100 μg/ml. The protective effect of P18 in mice was comparable to that of oseltamivir phosphate (Tamiflu). Further study will assess the potential of peptide P18 as an antiviral compound and as a promising candidate for the development of new antiviral vaccines.

Enhancement of Antioxidative and Intestinal Anti-inflammatory Activities of Glycated Milk Casein after Fermentation with Lactobacillus rhamnosus 4B15

In this study, we investigated the glycoproteomics of glycated milk casein (GMC) and GMC fermented by Lactobacillus rhamnosus 4B15 (FGMC) and determined their biological implications. There was a significant increase in the antioxidative and anti-inflammatory activities of GMC with galactose, which were higher than those of GMC with glucose (GMC-glc). Furthermore, the fermentation of GMC by L. rhamnosus 4B15 synergistically enhanced the above activities compared to those of unfermented GMC. Especially, fermented GMC-glc (FGMC-glc) possessed remarkably improved reducing power and radical scavenging activities. Moreover, FGMC-glc ameliorated the inflammatory response and tight junction-related intestinal epithelial dysfunction. Additionally, hexose-derived glycation and modification sites in protein sequences of GMC were identified. In particular, glycosylation and sulfation of serine and threonine residues were observed, and distinct modification sites were detected after fermentation. Therefore, these results indicated that glycation-induced modification of casein and fermentation correlated strongly with the enhanced functional properties.

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp

Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at -18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

Bifidobacteria and Their Health-Promoting Effects

Bifidobacteria are members of the intestinal microbiota of mammals and other animals, and some strains are able to exert health-promoting effects. The genus Bifidobacterium belongs to the Actinobacteria phylum. Firmicutes, Bacteroidetes, and Actinobacteria constitute the most abundant phyla in the human intestinal microbiota, Firmicutes and Bacteroidetes being predominant in adults, and Actinobacteria in breast-fed infants, where bifidobacteria can reach levels higher than 90% of the total bacterial population. They are among the first microbial colonizers of the intestines of newborns, and play key roles in the development of their physiology, including maturation of the immune system and use of dietary components. Indeed, some nutrients, such as human milk oligosaccharides, are important drivers of bifidobacterial development. Some Bifidobacterium strains are considered probiotic microorganisms because of their beneficial effects, and they have been included as bioactive ingredients in functional foods, mainly dairy products, as well as in food supplements and pharma products, alone, or together with, other microbes or microbial substrates. Well-documented scientific evidence of their activities is currently available for bifidobacteria-containing preparations in some intestinal and extraintestinal pathologies. In this review, we focus on the role of bifidobacteria as members of the human intestinal microbiota and their use as probiotics in the prevention and treatment of disease.

Differences between live and heat-killed bifidobacteria in the regulation of immune function and the intestinal environment

Probiotics are live microorganisms that confer a health benefit on the host, such as improvement of the intestinal environment, modulation of immune function and energy metabolism. Heat-killed probiotic strains have also been known to exhibit some physiological functions; however, the differences between live and heat-killed probiotics have not been well elucidated. In this study, we investigated the differences between live and heat-killed Bifidobacterium breve M-16V, a probiotic strain, in the regulation of immune function, intestinal metabolism and intestinal gene expression of the host using gnotobiotic mouse model and omics approaches. Both live and heat-killed cells of B. breve M-16V showed immune-modulating effects that suppressed pro-inflammatory cytokine production in spleen cells and affected intestinal metabolism; however, live cells exhibited a more remarkable effect in the regulation of intestinal metabolism and intestinal gene expression involved in nutrient metabolism. Our findings are valuable for considering the health benefits of live and heat-killed bacteria and the usefulness of different forms of probiotics.

Characterization of probiotic bacteria involved in fermented milk processing enriched with folic acid

Yogurt products fermented with probiotic bacteria are a consumer trend and a challenge for functional food development. So far, limited research has focused on the behavior of the various probiotic strains used in milk fermentation. In the present study, we characterized folic acid production and the sensory and textural characteristics of yogurt products fermented with probiotic bacteria. Yogurt fermented with Lactobacillus plantarum had improved nutrient content and sensory and textural characteristics, but the presence of L. plantarum significantly impaired the growth and survival of Lactobacillus delbrueckii ssp. bulgaricus during refrigerated storage. Overall, L. plantarum was a good candidate for probiotic yogurt fermentation; further studies are needed to understand the major metabolite path of lactic acid bacteria in complex fermentation.

Fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 reduces bacterial translocation in rats treated with carbon tetrachloride

Probiotics can prevent pathological bacterial translocation by modulating intestinal microbiota and improving the gut barrier. The aim was to evaluate the effect of a fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 on bacterial translocation in rats with carbon tetrachloride (CCl4)-induced cirrhosis. Sprague-Dawley rats treated with CCl4 were randomized into a probiotic group that received fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 in drinking water or a water group that received water only. Laparotomy was performed one week after ascites development. We evaluated bacterial translocation, intestinal microbiota, the intestinal barrier and cytokines in mesenteric lymph nodes and serum. Bacterial translocation decreased and gut dysbiosis improved in the probiotic group compared to the water group. The ileal β-defensin-1 concentration was higher and ileal malondialdehyde levels were lower in the probiotic group than in water group. There were no differences between groups in serum cytokines but TNF-α levels in mesenteric lymph nodes were lower in the probiotic group than in the water group. Fermented milk containing Lactobacillus paracasei subsp. paracasei CNCM I-1518 decreases bacterial translocation, gut dysbiosis and ileal oxidative damage and increases ileal β-defensin-1 expression in rats treated with CCl4, suggesting an improvement in the intestinal barrier integrity.

Gastric microbiota features associated with cancer risk factors and clinical outcomes: A pilot study in gastric cardia cancer patients from Shanxi, China

Little is known about the link between gastric microbiota and the epidemiology of gastric cancer. In order to determine the epidemiologic and clinical relevance of gastric microbiota, we used 16 S ribosomal RNA gene sequencing analysis to characterize the composition and structure of the gastric microbial community of 80 paired samples (non-malignant and matched tumor tissues) from gastric cardia adenocarcinoma (GCA) patients in Shanxi, China. We also used PICRUSt to predict microbial functional profiles. Compared to patients without family history of upper gastrointestinal (UGI) cancer in the non-malignant gastric tissue microbiota, patients with family history of UGI cancer had higher Helicobacter pylori (Hp) relative abundance (median: 0.83 vs. 0.38, p = 0.01) and lower alpha diversity (median observed species: 51 vs. 85, p = 0.01). Patients with higher (vs. lower) tumor grade had higher Hp relative abundance (0.73 vs. 0.18, p = 0.03), lower alpha diversity (observed species, 66 vs. 89, p = 0.01), altered beta diversity (weighted UniFrac, p = 0.002) and significant alterations in relative abundance of five KEGG functional modules in non-malignant gastric tissue microbiota. Patients without metastases had higher relative abundance of Lactobacillales than patients with metastases (0.05 vs. 0.01, p = 0.04) in non-malignant gastric tissue microbiota. These associations were observed in non-malignant tissues but not in tumor tissues. In conclusion, this study showed a link of gastric microbiota to a major gastric cancer risk factor and clinical features in GCA patients from Shanxi, China. Studies with both healthy controls and gastric cardia and noncardia cancer cases across different populations are needed to further examine the association between gastric cancer and the microbiota.

Unraveling the Differences between Gram-Positive and Gram-Negative Probiotics in Modulating Protective Immunity to Enteric Infections

The role of intestinal microbiota and probiotics in prevention and treatment of infectious diseases, including diarrheal diseases in children and animal models, is increasingly recognized. Intestinal commensals play a major role in development of the immune system in neonates and in shaping host immune responses to pathogens. Lactobacilli spp. and Escherichia coli Nissle 1917 are two probiotics that are commonly used in children to treat various medical conditions including human rotavirus diarrhea and inflammatory bowel disease. Although the health benefits of probiotics have been confirmed, the specific effects of these established Gram-positive (G+) and Gram-negative (G−) probiotics in modulating immunity against pathogens and disease are largely undefined. In this review, we discuss the differences between G+ and G− probiotics/commensals in modulating the dynamics of selected infectious diseases and host immunity. These probiotics modulate the pathogenesis of infectious diseases and protective immunity against pathogens in a species- and strain-specific manner. Collectively, it appears that the selected G− probiotic is more effective than the various tested G+ probiotics in enhancing protective immunity against rotavirus in the gnotobiotic piglet model.

Reduced microbial diversity in adult survivors of childhood acute lymphoblastic leukemia and microbial associations with increased immune activation

BACKGROUND

Adult survivors of childhood cancers such as acute lymphoblastic leukemia (ALL) have health problems that persist or develop years after cessation of therapy. These late effects include chronic inflammation-related comorbidities such as obesity and type 2 diabetes, but the underlying cause is poorly understood.

RESULTS

We compared the anal microbiota composition of adult survivors of childhood ALL (N = 73) with healthy control subjects (N = 61). We identified an altered community with reduced microbial diversity in cancer survivors, who also exhibit signs of immune dysregulation including increased T cell activation and chronic inflammation. The bacterial community among cancer survivors was enriched for Actinobacteria (e.g. genus Corynebacterium) and depleted of Faecalibacterium, correlating with plasma concentrations of IL-6 and CRP and HLA-DR+CD4+ and HLA-DR+CD8+ T cells, which are established markers of inflammation and immune activation.

CONCLUSIONS

We demonstrated a relationship between microbial dysbiosis and immune dysregulation in adult ALL survivors. These observations suggest that interventions that could restore microbial diversity may ameliorate chronic inflammation and, consequently, development of late effects of childhood cancer survivors.

A metagenomic study of the preventive effect of Lactobacillus rhamnosus GG on intestinal polyp formation in ApcMin/+ mice

AIMS

To investigate the in vivo effects of Lactobacillus rhamnosus GG (LGG) on intestinal polyp development and the interaction between this single-organism probiotic and the gut microbiota therein.

METHODS AND RESULTS

The Apc^Min/+ mouse model was used to study the potential preventive effect of LGG on intestinal polyposis, while shotgun metagenomic sequencing was employed to characterize both taxonomic and functional changes within the gut microbial community. We found that the progression of intestinal polyps in the control group altered the community functional profile remarkably despite small variation in the taxonomic diversity. In comparison, the consumption of LGG helped maintain the overall functional potential and taxonomic profile in the resident microbes, thereby leading to a 25% decrease of total polyp counts. Furthermore, we found that LGG enriched those microbes or microbial activities related to short-chain fatty acid production (e.g. Roseburia and Coprococcus), as well as suppressed the ones that can lead to inflammation (e.g. Bilophila wadsworthia).

CONCLUSIONS

Our study using shotgun metagenomics highlights how single probiotic LGG may exert its beneficial effects and decrease polyp formation in mice by maintaining gut microbial functionality.

SIGNIFICANCE AND IMPACT OF THE STUDY

This probiotic intervention targeting microbiota may be used in conjugation with other dietary supplements or drugs as part of prevention strategies for early-stage colon cancer, after further clinical validations in human.

Promotility Action of the Probiotic Bifidobacterium lactis HN019 Extract Compared with Prucalopride in Isolated Rat Large Intestine

Attention is increasingly being focussed on probiotics as potential agents to restore or improve gastrointestinal (GI) transit. Determining mechanism of action would support robust health claims. The probiotic bacterium Bifidobacterium lactis HN019 reduces transit time, but its mechanisms of action and effects on motility patterns are poorly understood. The aim of this study was to investigate changes in GI motility induced by an extract of HN019 on distinct patterns of colonic motility in isolated rat large intestine, compared with a known promotility modulator, prucalopride. The large intestines from male Sprague Dawley rats (3–6 months) were perfused with Kreb's buffer at 37°C in an oxygenated tissue bath. Isometric force transducers recorded changes in circular muscle activity at four independent locations assessing contractile propagation between the proximal colon and the rectum. HN019 extract was perfused through the tissue bath and differences in tension and frequency quantified relative to pre-treatment controls. Prucalopride (1 μM) increased the frequency of propagating contractions (by 75 ± 26%) in the majority of preparations studied (10/12), concurrently decreasing the frequency of non-propagating contractions (by 50 ± 11%). HN019 extract had no effect on contractile activity during exposure (n = 8). However, following wash out, contraction amplitude of propagating contractions increased (by 55 ± 18%) in the distal colon, while the frequency of non-propagating proximal contractions decreased by 57 ± 7%. The prokinetic action of prucalopride increased the frequency of synchronous contractions along the length of colon, likely explaining increased colonic rate of transit in vivo. HN019 extract modified motility patterns in a different manner by promoting propagating contractile amplitude and inhibiting non-propagations, also demonstrating prokinetic activity consistent with the reduction of constipation by B. lactis HN019 in humans.

Probiotics in early life: a preventative and treatment approach

Microbial colonization of the infant gut plays a key role in immunological and metabolic pathways impacting human health. Since the maturation of the gut microbiota coincides with early life development, failure to develop a health compatible microbiota composition may result in pathology and disease in later life. Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Maternal transfer of microorganisms is possible during pregnancy and lactation, and the mother's diet and microbiota can influence that of her offspring. Furthermore, pre-term birth, Caesarean section birth, formula feeding, antibiotic use, and malnutrition have been linked to dysbiosis, which in turn is associated with several pathologies such as necrotizing enterocolitis, inflammatory bowel diseases, antibiotic associated diarrhea, colic, and allergies. Thus, early life should represent a preferred stage of life for probiotic interventions. In this context, they could be regarded as a means to 'program' the individual for health maintenance, in order to prevent pathologies associated with dysbiosis. In order to elucidate the mechanisms underlying the benefits of probiotic administration, pre-clinical studies have been conducted and found an array of positive results such as improved microbial composition, intestinal maturation, decreased pathogenic load and infections, and improved immune response. Moreover, specific probiotic strains administered during the perinatal period have shown promise in attenuating severity of necrotizing enterocolitis. The mechanisms elucidated suggest that probiotic interventions in early life can be envisaged for disease prevention in both healthy offspring and offspring at risk of chronic disease.

Neonatal colonization of mice with LGG promotes intestinal development and decreases susceptibility to colitis in adulthood

Development of the intestinal microbiota during early life serves as a key regulatory stage in establishing the host-microbial relationship. This symbiotic relationship contributes to developing host immunity and maintaining health throughout the life span. This study was to develop an approach to colonize conventionally raised mice with a model probiotic bacterium, Lactobacillus rhamnosus GG (LGG), and to determine the effects of LGG colonization on intestinal development and prevention of colitis in adulthood. LGG colonization in conventionally raised was established by administering LGG to pregnant mice starting at gestational day 18 and pups at postnatal days 1- 5. LGG colonization promoted bodyweight gain and increased diversity and richness of the colonic mucosa-associated microbiota before weaning. Intestinal epithelial cell proliferation, differentiation, tight junction formation, and mucosal IgA production were all significantly enhanced in LGG-colonized mice. Adult mice colonized with LGG showed increased IgA production and decreased susceptibility to intestinal injury and inflammation induced in the dextran sodium sulfate model of colitis. Thus, neonatal colonization of mice with LGG enhances intestinal functional maturation and IgA production and confers lifelong health consequences on protection from intestinal injury and inflammation. This strategy might be applied for benefiting health in the host.

The Investigation of the Diversity of Lactobacilli Spp. and Assessment Their Some Probiotic Properties in Traditional Dairy Products in East Azerbaijan Province in Iran

Nowadays, there is an increasing interest in the production of functional foods, particularly probiotic foods. Lactic acid bacteria (LAB) particularly strains of Lactobacillus are important bacteria in food microbiology and human nutrition due to their ability to fermented food production and have received considerable attention as probiotics. The traditional fermented dairy foods as a rich source of wild LAB can introduce new Lactobacillus strain with probiotic properties into food products. So, the present study was aimed to isolate and identify Lactobacilli spp. in traditional dairy products and to assess some of their probiotic properties. For this study, fifty samples including homemade yogurt and cheese were purchased from several rural areas and the intragenic transcribed spacer-PCR (16-23s rDNA) was used for identification of Lactobacilli. Some probiotic properties were assayed including resistant to acid and bile, antimicrobial activity, and antibiotic susceptibility. The isolates were characterized as L.plantarum, L.casei, L.paracasei and L.rhamnosus. Out of the fifty-six isolates identified phenotypically as lactobacillus, twenty-four strains were tolerant to pH 2.5 and 0.3% bile salt after 3 h of incubation and only 6 strains showed antimicrobial activity and antibiotic susceptibility. In conclusion, six strains showed potentially probiotic properties including resistant to acid and bile, antimicrobial activity and antibiotic susceptibility. So, we can consider these strains as native probiotic but extra examinations were required for introduction into food products.

Resetting microbiota by Lactobacillus reuteri inhibits T reg deficiency-induced autoimmunity via adenosine A2A receptors

Regulatory T (T reg) cell deficiency causes lethal, CD4+ T cell-driven autoimmune diseases. Stem cell transplantation is used to treat these diseases, but this procedure is limited by the availability of a suitable donor. The intestinal microbiota drives host immune homeostasis by regulating the differentiation and expansion of T reg, Th1, and Th2 cells. It is currently unclear if T reg cell deficiency-mediated autoimmune disorders can be treated by targeting the enteric microbiota. Here, we demonstrate that Foxp3+ T reg cell deficiency results in gut microbial dysbiosis and autoimmunity over the lifespan of scurfy (SF) mouse. Remodeling microbiota with Lactobacillus reuteri prolonged survival and reduced multiorgan inflammation in SF mice. L. reuteri changed the metabolomic profile disrupted by T reg cell deficiency, and a major effect was to restore levels of the purine metabolite inosine. Feeding inosine itself prolonged life and inhibited multiorgan inflammation by reducing Th1/Th2 cells and their associated cytokines. Mechanistically, the inhibition of inosine on the differentiation of Th1 and Th2 cells in vitro depended on adenosine A2A receptors, which were also required for the efficacy of inosine and of L. reuteri in vivo. These results reveal that the microbiota-inosine-A2A receptor axis might represent a potential avenue for combatting autoimmune diseases mediated by T reg cell dysfunction.

Irritable bowel syndrome symptom severity improves equally with probiotic and placebo

AIM

To determine the effects of Lactobacillus acidophilus NCFM on irritable bowel syndrome (IBS) symptoms and quality of life (QoL).

METHODS

In this randomized triple-blind trial, adult IBS volunteers who were recruited according to Rome III criteria received 10⁹ or 10¹⁰ colony-forming units of NCFM or placebo daily for 12 wk. IBS Symptom Severity Score (IBS-SSS), which constituted the primary outcome, and secondary outcomes, including individual IBS symptoms, IBS-related QoL questionnaire, anxiety and depression, defecation frequency, and stool consistency, were assessed at baseline at the end of the 8-wk run-in period, after 4 and 12 wk of intervention, and after a 4-wk washout.

RESULTS

A total of 340 of 391 randomized volunteers completed the trial. IBS-SSS improved over 12 wk of treatment in all treatment groups, decreasing by a mean ± SD of 44.0 ± 80.2, 50.8 ± 82.4, and 48.3 ± 72.2 in the placebo, active low-dose, and active high-dose groups, respectively. Similarly, secondary outcomes did not differ between treatment groups. However, in a post hoc analysis of volunteers with moderate to severe abdominal pain at baseline (VAS > 35/100), the treatment significantly reduced the sensation of abdominal pain. Pain scores fell by 20.8 ± 22.8, 29.4 ± 17.9, and 31.2 ± 21.9 in the placebo, active low-dose, and active high-dose groups, respectively (P value for placebo vs combined active doses = 0.0460).

CONCLUSION

NCFM alleviates moderate to severe abdominal pain, consistent with earlier observations of this strain mitigating visceral pain through increased analgesic receptor expression.

The effect of perioperative probiotics treatment for colorectal cancer: short-term outcomes of a randomized controlled trial

This study was designed to mainly evaluate the anti-infective effects of perioperative probiotic treatment in patients receiving confined colorectal cancer (CRC) respective surgery. From November 2011 to September 2012, a total of 60 patients diagnosed with CRC were randomly assigned to receive probiotic (n = 30) or placebo (n = 30) treatment. The operative and post-operative clinical results including intestinal cleanliness, days to first - flatus, defecation, fluid diet, solid diet, duration of pyrexia, average heart rate, length of intraperitoneal drainage, length of antibiotic therapy, blood index changes, rate of infectious and non-infectious complications, postoperative hospital stay, and mortality were investigated. The patient demographics were not significantly different (p > 0.05) between the probiotic treated and the placebo groups. The days to first flatus (3.63 versus 3.27, p = 0.0274) and the days to first defecation (4.53 versus 3.87, p = 0.0268) were significantly improved in the probiotic treated patients. The incidence of diarrhea was significantly lower (p = 0.0352) in probiotics group (26.67%, 8/30) compared to the placebo group (53.33%, 16/30). There were no statistical differences (p > 0.05) in other infectious and non-infectious complication rates including wound infection, pneumonia, urinary tract infection, anastomotic leakage, and abdominal distension. In conclusion, for those patients undergoing confined CRC resection, perioperative probiotic administration significantly influenced the recovery of bowel function, and such improvement may be of important clinical significance in reducing the short-term infectious complications such as bacteremia.