Interactions of lactic acid bacteria with human intestinal epithelial cells: effects on cytokine production

Effect of Fermented Soybean (FSB) Supplementation on Gastroesophageal Reflux Disease (GERD)

Gastroesophageal reflux disease (GERD) is a prevalent chronic condition affecting the well-being of both adults and children in general medical practice. Research on the effects of fermented soybean (SB) supplementation in managing GERD is relatively new, with limited studies available. The existing research often lacks sufficient dosing regimens and study durations to differentiate between transient placebo effects and sustained benefits. In this study, the beneficial effects of FSB supplementation were investigated in 110 voluntary participants (NCT06524271). The participants were required to take 1 g of FSB supplement once daily for 12 weeks. GERD symptoms were evaluated using the Reflux Disease Questionnaire (RDQ), while inflammatory markers, including interleukin-4 (IL-4), interleukin-6 (IL-6), and interleukin-8 (IL-8), were measured to assess inflammation. The Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire was used to evaluate participants' quality of life. The results indicated that FSB supplementation significantly (p < 0.05) alleviated heartburn and regurgitation symptoms and reduced levels of IL-4, IL-6, and IL-8, indicating a notable anti-inflammatory effect. Additionally, significant (p < 0.05) improvements were observed in QOLRAD scores, particularly in vitality, emotional distress, and physical/social functioning. Collectively, our findings support the use of FSB as an adjuvant approach in managing GERD, with notable improvements in patients' quality of life.

The anticancer effect of potential probiotic L. fermentum and L. plantarum in combination with 5-fluorouracil on colorectal cancer cells

5-Fluorouracil (5-FU) is an effective chemotherapy drug in the treatment of colorectal cancer (CRC). However, auxiliary or alternative therapies must be sought due to its resistance and potential side effects. Certain probiotic metabolites exhibit anticancer properties. In this study evaluated the anticancer and potential therapeutic activities of cell extracts potential probiotic strains, Limosilactobacillus fermentum and Lactiplantibacillus plantarum isolated from the mule milk and the standard probiotic strain Lacticaseibacillus rhamnosus GG (LGG) against the human colon cancer cell line (HT-29) and the normal cell line (HEK-293) alone or in combination with 5-FU. In this study, L. plantarum and L. fermentum, which were isolated from mule milk, were identified using biochemical and molecular methods. Their probiotic properties were investigated in vitro and compared with the standard probiotic strain of the species L. rhamnosus GG. The MTT assay, acridine orange/ethidium bromide (AO/EB) fluorescent staining, and flow cytometry were employed to measure the viability of cell lines, cell apoptosis, and production rates of Th17 cytokines, respectively. The results demonstrated that the combination of lactobacilli cell extracts and 5-FU decreased cell viability and induced apoptosis in HT-29 cells. Furthermore, this combination protected HEK-293 cells from the cytotoxic effects of 5-FU, enhancing their viability and reducing apoptosis. Moreover, the combination treatment led to an increase in the levels of IL-17A, IFN-γ, and TNF-α, which can enhance anti-tumor immunity. In conclusion, the cell extracts of the lactobacilli strains probably can act as a potential complementary anticancer therapy.

The effect of an acute aspirin challenge on intestinal permeability in healthy adults with and without prophylactic probiotic consumption: a double-blind, placebo-controlled, randomized trial

BACKGROUND

Healthy individuals may experience increases in intestinal permeability after chronic or acute use of non-steroidal anti-inflammatory drugs, which may be attenuated by probiotics. This study investigates the effects of an acute aspirin challenge on gastroduodenal barrier function with or without prophylactic probiotic consumption.

METHODS

Twenty-nine generally healthy participants (26 ± 6 years) completed a 14-week randomized, double-blind, crossover trial. A probiotic containing 2 Lactobacilli strains or placebo was administered for 3 weeks, with a 4-week washout period between crossover phases. Daily and weekly questionnaires assessing gastrointestinal function were completed for 2 weeks before until 2 weeks after each intervention to assess gastrointestinal function. Gastroduodenal permeability was assessed by urinary excretion of orally administered sucrose after 1, 2, and 3 weeks of each intervention with a 1950 mg-aspirin challenge after 2 weeks of supplementation. Stool samples were collected weekly during supplementation for detection of species of interest.

RESULTS

Gastroduodenal permeability increased with aspirin challenge (Week 1: 3.4 ± 0.6 μmol vs Week 2: 9.9 ± 1.0 μmol urinary sucrose; p < 0.05). There were no differences in the change in permeability after the aspirin challenge or gastrointestinal function between interventions.

CONCLUSION

The acute aspirin challenge significantly increased intestinal permeability similarly in both groups, and prophylactic probiotic consumption was unable to prevent the loss in this particular model.

Reduction in mucosa thickness is associated with changes in immune function in the colon mucosa during the weaning transition in Holstein bull dairy calves

This study aims to characterize changes in the structure and the molecules related to immune function in the colon mucosa in dairy calves during the weaning transition (weaned at week 6 of age). Colon mucosa thickness, measured at week 5 to 8 and 12 of age, decreased for 2 weeks after weaning, but then recovered. Colon mucosa's transcriptome profiling at week 5, 7, and 12 of age was obtained using RNA-sequencing. Functional analysis showed that pathways related to immune function were up-regulated postweaning. A weighted gene co-expression network analysis identified 17 immune function related genes, expressed higher postweaning, which were negatively correlated with colon mucosa thickness, suggesting that these genes may be involved in colon mucosa inflammation and recovery from mucosa thickness decrement during the weaning transition. As such, it is important to determine the function of immune cells in the colon mucosa during the weaning transition in dairy calves.

The Bioavailability of Glycyrrhizinic Acid Was Enhanced by Probiotic Lactobacillus rhamnosus R0011 Supplementation in Liver Fibrosis Rats

Glycyrrhizinic acid (GL) is clinically applied to treat liver injury, and the bioavailability of orally administered GL is closely related to the gut microbiota. Therefore, the dysbiosis of gut flora in liver injury could significantly influence GL bioavailability. Still, less is known about the impact of probiotic supplementation on the bio-absorption process of oral medication, especially under a pathological state. Herein, probiotic L. rhamnosus R0011 (R0011) with a high viability in the harsh gastrointestinal environment was selected, and the effect of R0011 on the GL bioavailability in rats was investigated. Four groups of rats (n = 6 per group) were included: the normal group (N group), the normal group supplemented with R0011 (NLGG group), CCl4-induced chronic liver injury model (M group), and the model group supplemented with R0011 (MLGG group). Our results showed that liver injury was successfully induced in the M and MLGG groups via an intraperitoneal injection of 50% (v/v) CCl4 solution. Healthy rats supplemented with R0011 could increase the bioavailability of GL by 1.4-fold compared with the normal group by plasma pharmacokinetic analysis. Moreover, the GL bioavailability of MLGG group was significantly increased by 4.5-fold compared with the model group. R0011 directly improved gut microbial glucuronidase and downregulated the host intestinal drug transporter gene expression of multidrug resistance protein 2 (MRP2). More critically, R0011 restored the gut microbiota composition and regulated the metabolic function, significantly enhancing the microbial tryptophan metabolic pathway compared with the pathological state, which may indirectly promote the bioavailability of GL. Overall, these data may provide possible strategies by which to address the low bioavailability of traditional medicine through probiotic intervention.

Gut microbiome and fecal metabolic alteration in systemic lupus erythematosus patients with depression

Background

Mental health disorders in systemic lupus erythematosus (SLE) are gradually getting recognized; however, less is known regarding the actual structure and compositional alterations in gut microbiome and metabolism and the mechanisms of how they affect depression development in SLE patients.

Methods

Twenty-one SLE patients with depression (SLE-d), 17 SLE patients without depression (SLE-nd), and 32 healthy controls (HC) were included in this study. Fecal samples were collected for 16S rRNA gene sequencing and ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) based metabolomics.

Results

The structure of gut microbiome in the SLE-d group changed compared with that in the other two groups. The microbiome composition of SLE-d group showed decreased species richness indices, characterized by low ACE and Chao1 indices, a decrease in the ratio of phylum Firmicutes to Bacteroidetes, genus Faecalibacterium and Roseburia. A downregulation of the metabolite fexofenadine involved in bile secretion was positively correlated with the genus Faecalibacterium, Subdoligranulum and Agathobacter. Compared with the SLE-nd group, the SLE-d group had elevated serum levels of IL-2 and IL-6 and decreased BDNF. Interestingly, abundance of the genus Faecalibacterium and Roseburia was negatively correlated with IL-6, abundance of the genus Roseburia was negatively correlated with IL-2, and abundance of the genus Bacteroides was positively correlated with IL-2.

Conclusion

This study identified specific fecal microbes and their metabolites that may participate in the development of SLE-d. Our findings provide a new perspective for improving depression in SLE patients by regulating the gut-brain axis.

Prebiotic, Antipathogenic Bacteria and Hypocholesterolemia Properties of Fermented Rice Bran Extracts Derived from Black Rice and Germinated Brown Rice

Rice bran is a rich source of health-promoting nutrition and bioactive compounds; nevertheless, the properties of rice brans depend on cultivars, ages, and preparation methods, drawing the potential of raw materials for health benefits. Therefore, this research aimed to investigate the health-promoting properties of fermented rice bran extracts from cultivar black rice (H7F) and germinated brown rice (G13F), focusing on their prebiotic, antipathogenic bacteria activity and safety demonstrated in vitro and in vivo study models, respectively. Here, the screening of metabolites' change after rice bran fermentation by ATR-FTIR spectra revealed specific peaks corresponding to the composited components of protein, carbohydrate, and lipid. Then, in the in vitro study, the prebiotic capability of H7F and G13F extracts was demonstrated by a growth-promoting effect on Lactobacillus delbrueckii subsp. lactis under specific acidic conditions. Furthermore, antipathogenic bacterial activity against Escherichia coli and Staphylococcus aureus was presented at 25 mg/mL of MIC values and 50 mg/mL of MBC of both fermented rice bran extracts, eliminating the bacteria by interfering with the biofilm formation. For safety, an acute and chronic toxicity study using Wistar rats was conducted, in which changes in the body and organ weights, histopathology of organs, blood chemistry, and hematological parameters were observed after H7F and G13F treatment. Desirably, they showed no toxicity, with a significant reduction in blood cholesterol levels in the chronic treatment of H7F and G13F. Conclusively, the overall results evidenced the health benefits of H7F and G13F related to their prebiotic and antipathogenic bacteria properties and hypocholesterolemia potential with a high level of safety. Therefore, the fermented rice bran extracts were demonstrated as potential materials for the further development of functional ingredients and health products.

Effects of Taro (Colocasia esculenta) Water-Soluble Non-Starch Polysaccharide, Lactobacillus acidophilus, Bifidobacterium breve, Bifidobacterium infantis, and Their Synbiotic Mixtures on Pro-Inflammatory Cytokine Interleukin-8 Production

In the past decades, the regulation of pro-inflammatory cytokine production, including interleukin-8 (IL-8), has been the goal of many targeted therapeutic interventions for Necrotising enterocolitis (NEC), a gastrointestinal disease commonly associated with a very low birth weight in preterm infants. In this study, the ability to regulate the production of IL-8 of the water-soluble non-starch polysaccharide (WS-NSP) from taro corm (Tc-WS-NSP) extracted using a conventional (CE) or improved conventional (ICE) extraction method, of the probiotics Lactobacillus acidophilus, Bifidobacterium breve, and Bifidobacterium infantis, and their synbiotic mixtures were evaluated. The TNF-α stimulated HT-29 cells were incubated with undigested or digested Tc-WS-NSPs (CE or ICE), probiotics, and their synbiotic mixtures with Klebsiella oxytoca, an NEC-positive-associated pathogen. Overall, the synbiotic mixtures of digested Tc-WS-NSP-ICE and high bacterial concentrations of L. acidophilus (5.57 × 10⁹), B. breve (2.7 × 10⁸ CFU/mL), and B. infantis (1.53 × 10⁸) demonstrated higher (42.0%, 45.0%, 43.1%, respectively) ability to downregulate IL-8 compared to the sole use of Tc-WS-NSPs (24.5%), or the probiotics L. acidophilus (32.3%), B. breve (37.8%), or B. infantis (33.1%). The ability demonstrated by the Tc-WS-NSPs, the probiotics, and their synbiotics mixtures to downregulate IL-8 production in the presence of an NEC-positive-associated pathogen may be useful in the development of novel prophylactic agents against NEC.

Gastro-Protective Effect of Fermented Soybean (Glycine max (L.) Merr.) in a Rat Model of Ethanol/HCl-Induced Gastric Injury

The present research purposed to examine the gastro-protective effect of Glycine max (L.) Merr. fermented using Lactobacillus delbrueckii ssp. delbrueckii Rosell-187 (Gastro-AD®) on ethanol/HCl-induced gastric damage, specifically on gastric acid secretion. After oral supplementation of Gastro-AD® to Sprague-Dawley (SD) rats with ethanol/HCl-induced gastric damage, we determined that Gastro-AD® attenuated the gastric mucosal lesion, hemorrhage and gastric acid secretion induced by ethanol/HCl. In addition, we observed that the Gastro-AD® treatment increased the serum prostaglandin E2 level and decreased the levels of gastric acid secretion-related receptors in both gastric tissues and primary gastric parietal cells. Furthermore, it decreased the levels of inflammatory factors, including serum histamine and expression of p-IκB, p-p65, iNOS and COX-2 and the activity of apoptotic signaling pathways, including those involving p-JNK, Bcl2/Bax, Fas, FADD, caspase-8 and caspase-3, in the stomach of the ethanol/HCl-treated rats. Thus, we suggest that Gastro-AD® supplementation may reduce ethanol/HCl-induced gastric acid secretion and prevent gastric injury.

The effect of Lacticaseibacillus casei on inflammatory cytokine (IL-8) gene expression induced by exposure to Shigella sonnei in Zebrafish (Danio rerio)

ABSTRACT This study aimed to evaluate the protective function of probiotics against Shigella sonnei pathogenicity. For this purpose, 400 zebrafish were divided into four groups with two replications: (T1): receiving Lacticaseibacillus casei for 27 days, (T2): receiving L. casei for 27 days followed by 72 hr exposure to S. sonnei, (T3): receiving basal diet for 27 days followed by 72 hr exposure to S. sonnei, and control group (C): receiving basal diet without exposure to the pathogen. According to the results, feeding with L. casei for 27 days reduced the interleukin-8 (IL-8) expression significantly (P<0.05). The results showed a decrease in IL-8 expression in the group exposed to the pathogen and fed with the probiotic compared to the group only fed with the basal diet (P<0.05). Considering the role of IL-8 as a pro-inflammatory cytokine, our results indicated that feeding with L. casei could modulate inflammatory responses.

Bi-Directionality of the Microbiota-Gut-Brain Axis in Patients With Functional Dyspepsia: Relevance of Psychotherapy and Probiotics

Functional dyspepsia is one of the most commonly diagnosed disorders of the gut-brain interaction worldwide. The precise pathogenesis of functional dyspepsia is complex and remains incompletely understood. Therefore, advances in the understanding of functional dyspepsia could change clinical practice. The aim of this review is to highlight the relevance of psychotherapy and probiotics in the context of the microbiota-gut-brain axis in the pathophysiology and especially in the treatment of functional dyspepsia. Therefore, studies which have been conducted to investigate the role of psychotherapy and probiotics in FD and the microbiota-gut-brain axis in the pathophysiology of functional dyspepsia were examined, and the outcomes of this research summarized. There might be a link between changes in the microbiome and functional dyspepsia. Even though, specific alterations in the microbiome that may be pathognomonic in functional dyspepsia remain unclear, the use of probiotics became a viable treatment option for patients with functional dyspepsia. Since mental illness also plays an important role in the pathophysiology of functional dyspepsia, psychotherapy is a useful treatment method, with additional study results indicating that psychotherapy may also shift the microbiome in a favorable direction. Moreover, other findings suggest that probiotics can be used not only to alleviate gastrointestinal symptoms in functional dyspepsia, but also to treat or even prevent mental disorders in these patients. In summary, in this review we highlight the bi-directionality of the microbiota-gut-brain axis in the pathophysiology of functional dyspepsia. Although there are multiple treatment approaches, the burden of disease in patients with functional dyspepsia is still enormous and a definitive therapy to cure this disease does not (yet) exist. Lastly, there is a lack of studies on the impact of dysbiosis, mental health and probiotics on pathophysiology and symptomatology in functional dyspepsia which should be investigated in future studies.

Identification of Lactobacillus Strains Capable of Fermenting Fructo-Oligosaccharides and Inulin

Novel probiotic strains that can ferment prebiotics are important for functional foods. The utilization of prebiotics is strain specific, so we screened 86 Lactobacillus strains and compared them to Bifidobacterium breve 2141 for the ability to grow and produce SCFA when 1% inulin or fructo-oligosaccharides (FOS) were provided as the carbon source in batch fermentations. When grown anaerobically at 32 °C, ten Lactobacillus strains grew on both prebiotic substrates (OD₆₀₀ ≥ 1.2); while Lactobacillus coryniformis subsp. torquens B4390 grew only in the presence of inulin. When the growth temperature was increased to 37 °C to simulate the human body temperature, four of these strains were no longer able to grow on either prebiotic. Additionally, L. casei strains 4646 and B441, and L. helveticus strains B1842 and B1929 did not require anaerobic conditions for growth on both prebiotics. Short-chain fatty acid analysis was performed on cell-free supernatants. The concentration of lactic acid produced by the ten Lactobacillus strains in the presence of prebiotics ranged from 73-205 mM. L. helveticus B1929 produced the highest concentration of acetic acid ~19 mM, while L. paraplantarum B23115 and L. paracasei ssp. paracasei B4564 produced the highest concentrations of propionic (1.8-4.0 mM) and butyric (0.9 and 1.1 mM) acids from prebiotic fermentation. L. mali B4563, L. paraplantarum B23115 and L. paracasei ssp. paracasei B4564 were identified as butyrate producers for the first time. These strains hold potential as synbiotics with FOS or inulin in the development of functional foods, including infant formula.

Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is an inflammatory disease affecting premature infants. Intestinal microbial composition may play a key role in determining which infants are predisposed to NEC and when infants are at highest risk of developing NEC. It is unclear how to optimize antibiotic therapy in preterm infants to prevent NEC and how to optimize antibiotic regimens to treat neonates with NEC. This article discusses risk factors for NEC, how dysbiosis in preterm infants plays a role in the pathogenesis of NEC, and how probiotic and antibiotic therapy may be used to prevent and/or treat NEC and its sequelae.

Effect of a novel fermented soy product on gastric ulcer scores in horses

Non-pharmaceutical methods are desirable to treat or prevent gastric ulceration in horses. This two-period, randomised, double-blinded placebo-controlled study was designed to evaluate the efficacy of dietary supplementation (25 g once daily in feed for 30 days) with Fermaid®Ease 187 (FE, Lallemand Australia Pty Ltd, Maroochydore, Australia) on gastric squamous and glandular mucosal ulcer scores in horses. Gastroscopy of 120 horses presented to the Veterinary Clinical Centre at Charles Sturt University (CSU; Bathurst, Australia) or at local training establishments identified 60 horses with spontaneous gastric ulcer disease (50%). Of horses eligible for inclusion, 29 horses were recruited and randomised to receive either the FE or placebo for 30 days. Effects were assessed by repeat gastroscopy (Day 31), at which time horses started the reciprocal treatment. Eleven horses successfully completed both treatment periods. Treatment with FE showed a significant decrease in squamous ulcer scores in period 1 (P=0.008), with a similar effect observed in period 2. No change was observed in squamous ulcer scores for horses receiving placebo treatment in period 1, but increased squamous scores were observed in horses receiving placebo treatment in period 2 (P=0.062). Squamous ulcer scores on Day 31 were significantly lower (P=0.005) following FE treatment than for horses receiving the placebo treatment. No effects were observed on glandular ulcer scores. This study supported the use of FE in horses predisposed to ulceration of the squamous gastric mucosa.

Fermented soy supplementation improves indicators of quality of life: a randomized, placebo-controlled, double-blind trial in adults experiencing heartburn

Objective

To determine if fermented soy supplementation relieves heartburn and improves gastrointestinal symptoms and quality of life, a randomized, double-blind parallel study was conducted with adults experiencing mild or moderate heartburn. Participants consumed up to 3, 1 g sachets of flavored, Lactobacillus delbrueckii fermented with soy flour (n = 23) or placebo (maltodextrin) (n = 27) sachets per heartburn incident as needed for 3 weeks. Symptom intensity at 5, 15, and 30 min post-administration was assessed using a Likert-like scale. The Gastrointestinal Symptoms Rating Scale (GSRS) and Gastro-esophageal Reflux Disease Quality of Life Questionnaire (GERD-QOL) were administered at baseline, post-intervention and following a 1-week washout.

Results

No significant differences between groups were seen for heartburn severity or frequency, GSRS syndromes, or GERD-QOL domains. However, individual QOL items related to inconvenience of taking medications, fear of eating, inability to concentrate at work, and disturbance of after-meal activities and rest improved with fermented soy compared to placebo. Frequency of heartburn, diarrhea, and bloating improved during washout vs. baseline for the fermented soy group compared to placebo. Lactobacillus delbrueckii fermented soy supplementation improved QOL indicators and may decrease heartburn occurrence over time vs. an acute effect; efficacy of daily intake and longer duration requires investigation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-020-05205-z) contains supplementary material, which is available to authorized users.

IRT5 Probiotics Changes Immune Modulatory Protein Expression in the Extraorbital Lacrimal Glands of an Autoimmune Dry Eye Mouse Model

Purpose

While the association between the gut microbiome and the immune system has been studied in autoimmune disorders, little is known about ocular disease. Previously we reported that IRT5, a mixture of five probiotic strains, could suppress autoimmune dry eye. In this study, we investigated the mechanism by which IRT5 performs its immunomodulatory function in a mouse model of autoimmune dry eye.

Methods

NOD.B10.H2b mice were used as an autoimmune dry eye model. Either IRT5 or PBS was gavaged orally for 3 weeks, with or without 5 days of antibiotic pretreatment. The effects on clinical features, extraorbital lacrimal gland and spleen proteins, and fecal microbiota were analyzed.

Results

The ocular staining score was lower, and tear secretion was higher, in the IRT5-treated groups than in the PBS-treated groups. After IRT5 treatment, the downregulated lacrimal gland proteins were enriched in the biological processes of defense response and immune system process. The relative abundances of 33 operational taxonomic units were higher, and 53 were lower, in the feces of the IRT5-treated groups than in those of the PBS-treated groups. IRT5 administration without antibiotic pretreatment also showed immunomodulatory functions with increases in the Lactobacillus helveticus group and Lactobacillus hamsteri. Additional proteomic assays revealed a decrease of proteins related to antigen-presenting processes in the CD11b⁺ and CD11c⁺ cells of spleen in the IRT5-treated groups.

Conclusions

Changes in the gut microbiome after IRT5 treatment improved clinical manifestations in the autoimmune dry eye model via the downregulation of antigen-presenting processes in immune networks.

Effects of dietary supplementation of the lignocelluloses FibreCell and OptiCell on performance, expression of inflammation-related genes and the gut microbiome of broilers

This study investigated the hypothesis that dietary supplementation of lignocellulose in broilers influences the gut bacterial population and bacterial fermentation, has anti-inflammatory effects, and increases mucin synthesis in the intestine, and, through these changes, influences broiler performance positively. Day-old male Cobb 500 broilers (n = 96) were allotted to 3 experimental groups and fed 3 different maize-wheat-soybean meal-based basal diets during days 1 to 10, 11 to 21, and 22 to 35. The basal diets were fed to the control group, and were supplemented with 0.8% of a standard lignocellulose (LCS) or a fermentable lignocellulose (LCF). Body weight and feed consumption were determined, and at slaughter (day 35), carcass and gizzard weights and gizzard content pH were recorded, and samples of jejunum, cecum, and colon mucosa and of cecum digesta were collected from 15 birds/group. Growth performance and feed intake were not influenced, but dressing percentage was higher in group LCF compared to the other groups. In group LCS and the control group, performance, gizzard weight and gizzard content pH, intestinal gene expression of pro-inflammatory cytokines and of the mucins 2, 5ac and 13, the cecal short-chain fatty acid (SCFA) profile, and bacterial diversity were similar, and relative abundance of bacterial groups (16S DNA sequencing) differed. Supplementation of LCF decreased the expression of the pro-inflammatory genes encoding interleukins 1ß and 17 (P < 0.05) and those of 2 and 8 (P < 0.10) in the jejunum only. The bacterial population differed, and the SCFA profile shifted toward acetate at the expense of butyrate in group LCF compared to the control group. For example, the abundance of Firmicutes and of Ruminococcaceae and Lactobacillaceae decreased, whereas those of Peptostreptococcaceae, Erysipelotrichaceae, and Enterobacteriaceae and that of members of the phylum Proteobacteria increased in group LCF compared to the control group. These data indicate that the susceptibility of lignocellulose to fermentation is crucial for mediating its effects on intestinal gene expression and the bacterial population in the cecum, which may also affect dressing percentage.

Multicenter Trial of a Combination Probiotic for Children with Gastroenteritis

BACKGROUND

Gastroenteritis accounts for approximately 1.7 million visits to the emergency department (ED) by children in the United States every year. Data to determine whether the use of probiotics improves outcomes in these children are lacking.

METHODS

We conducted a randomized, double-blind trial involving 886 children 3 to 48 months of age with gastroenteritis who presented to six pediatric EDs in Canada. Participants received a 5-day course of a combination probiotic product containing Lactobacillus rhamnosus R0011 and L. helveticus R0052, at a dose of 4.0×10⁹ colony-forming units twice daily or placebo. The primary outcome was moderate-to-severe gastroenteritis, which was defined according to a post-enrollment modified Vesikari scale symptom score of 9 or higher (scores range from 0 to 20, with higher scores indicating more severe disease). Secondary outcomes included the duration of diarrhea and vomiting, the percentage of children who had unscheduled physician visits, and the presence or absence of adverse events.

RESULTS

Moderate-to-severe gastroenteritis within 14 days after enrollment occurred in 108 of 414 participants (26.1%) who were assigned to probiotics and 102 of 413 participants (24.7%) who were assigned to placebo (odds ratio, 1.06; 95% confidence interval [CI], 0.77 to 1.46; P=0.72). After adjustment for trial site, age, detection of rotavirus in stool, and frequency of diarrhea and vomiting before enrollment, trial-group assignment did not predict moderate-to-severe gastroenteritis (odds ratio, 1.06; 95% CI, 0.76 to 1.49; P=0.74). There were no significant differences between the probiotic group and the placebo group in the median duration of diarrhea (52.5 hours [interquartile range, 18.3 to 95.8] and 55.5 hours [interquartile range, 20.2 to 102.3], respectively; P=0.31) or vomiting (17.7 hours [interquartile range, 0 to 58.6] and 18.7 hours [interquartile range, 0 to 51.6], P=0.18), the percentages of participants with unscheduled visits to a health care provider (30.2% and 26.6%; odds ratio, 1.19; 95% CI, 0.87 to 1.62; P=0.27), and the percentage of participants who reported an adverse event (34.8% and 38.7%; odds ratio, 0.83; 95% CI, 0.62 to 1.11; P=0.21).

CONCLUSIONS

In children who presented to the emergency department with gastroenteritis, twice-daily administration of a combined L. rhamnosus-L. helveticus probiotic did not prevent the development of moderate-to-severe gastroenteritis within 14 days after enrollment. (Funded by the Canadian Institutes of Health Research and others; PROGUT ClinicalTrials.gov number, NCT01853124 .).

Suppression of Intestinal Epithelial Cell Chemokine Production by Lactobacillus rhamnosus R0011 and Lactobacillus helveticus R0389 Is Mediated by Secreted Bioactive Molecules

Host intestinal epithelial cells (IEC) present at the gastrointestinal interface are exposed to pathogenic and non-pathogenic bacteria and their products. Certain probiotic lactic acid bacteria (LAB) have been associated with a range of host-immune modulatory activities including down-regulation of pro-inflammatory gene expression and cytokine production by IEC, with growing evidence suggesting that these bacteria secrete bioactive molecules with immunomodulatory activity. The aim of this study was to determine whether two lactobacilli with immunomodulatory activity [Lactobacillus rhamnosus R0011 (Lr) and Lactobacillus helveticus R0389 (Lh)], produce soluble mediators able to influence IEC responses to Pattern Recognition Receptor (PRR) ligands and pro-inflammatory cytokines [Tumor Necrosis Factor α (TNFα), Interleukin-1β (IL-1β)], signals inducing IEC chemokine production during infection. To this end, the effects of cell-free supernatants (CFS) from Lr and Lh on IEC production of the pro-inflammatory chemokines interleukin (IL)-8 and cytokine-induced neutrophil chemoattractant 1 (CINC-1) induced by a range of host- or pathogen-derived pro-inflammatory stimuli were determined, and the impact on human HT-29 IEC and a primary IEC line (rat IEC-6) was compared. The Lr-CFS and Lh-CFS did not significantly modulate basal IL-8 production from HT-29 IECs or CINC-1 production from IEC-6 cells. However, both Lr-CFS and Lh-CFS significantly down-regulated IL-8 production from HT-29 IECs challenged with varied PRR ligands. Lr-CFS and Lh-CFS had differential effects on PRR-induced CINC-1 production by rat IEC-6 IECs, with no significant down-regulation of CINC-1 observed from IEC-6 IECs cultured with Lh-CFS. Further analysis of the Lr-CFS revealed down-regulation of IL-8 production induced by the pro-inflammatory cytokines IL-1β and TNFα Preliminary characterization of the bioactive constituent(s) of the Lr-CFS indicates that it is resistant to treatment with DNase, RNase, and an acidic protease, but is sensitive to alterations in pH. Taken together, these results indicate that these lactobacilli secrete bioactive molecules of low molecular weight that may modulate host innate immune activity through interactions with IEC.

A double-blind, randomized, placebo-controlled trial of Lactobacillus helveticus and Bifidobacterium longum for the symptoms of depression

OBJECTIVES

This trial investigated whether probiotics improved mood, stress and anxiety in a sample selected for low mood. We also tested whether the presence or severity of irritable bowel syndrome symptoms, and levels of proinflammatory cytokines, brain-derived neurotrophic factor and other blood markers, would predict or impact treatment response.

METHOD

Seventy-nine participants (10 dropouts) not currently taking psychotropic medications with at least moderate scores on self-report mood measures were randomly allocated to receive either a probiotic preparation (containing Lactobacillus helveticus and Bifidobacterium longum) or a matched placebo, in a double-blind trial for 8 weeks. Data were analysed as intent-to-treat.

RESULTS

No significant difference was found between the probiotic and placebo groups on any psychological outcome measure (Cohen's d range = 0.07-0.16) or any blood-based biomarker. At end-point, 9 (23%) of those in the probiotic group showed a ⩾60% change on the Montgomery-Åsberg Depression Rating Scale (responders), compared to 10 (26%) of those in the placebo group ([Formula: see text], p = ns). Baseline vitamin D level was found to moderate treatment effect on several outcome measures. Dry mouth and sleep disruption were reported more frequently in the placebo group.

CONCLUSIONS

This study found no evidence that the probiotic formulation is effective in treating low mood, or in moderating the levels of inflammatory and other biomarkers. The lack of observed effect on mood symptoms may be due to the severity, chronicity or treatment resistance of the sample; recruiting an antidepressant-naive sample experiencing mild, acute symptoms of low mood, may well yield a different result. Future studies taking a preventative approach or using probiotics as an adjuvant treatment may also be more effective. Vitamin D levels should be monitored in future studies in the area. The results of this trial are preliminary; future studies in the area should not be discouraged.

Effectiveness of Lactobacillus helveticus and Lactobacillus rhamnosus for the management of antibiotic-associated diarrhoea in healthy adults: a randomised, double-blind, placebo-controlled trial

Broad-spectrum antibiotic use can disrupt the gastrointestinal microbiota resulting in diarrhoea. Probiotics may be beneficial in managing this type of diarrhoea. The aim of this 10-week randomised, double-blind, placebo-controlled, parallel study was to investigate the effect of Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011 supplementation on antibiotic-associated diarrhoea in healthy adults. Subjects were randomised to receive 1 week of amoxicillin-clavulanic acid (875 mg/125 mg) once per day, plus a daily dose of 8×109 colony-forming units of a multi-strain probiotic (n 80) or placebo (n 80). The probiotic or placebo intervention was maintained for 1 week after completion of the antibiotic. Primary study outcomes of consistency and frequency of bowel movements were not significantly different between the probiotic and placebo groups. The secondary outcomes of diarrhoea-like defecations, Gastrointestinal Symptoms Rating Scale scores, safety parameters and adverse events were not significantly different between the probiotic intervention and the placebo. A post hoc analysis on the duration of diarrhoea-like defecations showed that probiotic intervention reduced the length of these events by 1 full day (probiotic, 2·70 (sem 0·36) d; placebo, 3·71 (sem 0·36) d; P=0·037; effect size=0·52). In conclusion, this study provides novel evidence that L. helveticus R0052 and L. rhamnosus R0011 supplementation significantly reduced the duration of diarrhoea-like defecations in healthy adults receiving antibiotics.

Calcium phosphate supplementation increases faecal Lactobacillus spp. in a randomised trial of young adults

The aim of the studies was to determine the effects of calcium carbonate and calcium phosphate supplementation on faecal Lactobacillus spp., with and without a probiotic supplement, in healthy adults. Study 1 comprised of a randomised, double-blind, crossover design; participants (n=15) received 2 capsules/d of 250 mg elemental calcium as calcium carbonate (Ca1) and calcium phosphate (Ca2) each for 2-week periods, with 2-week baseline and washout periods. Study 2 was a randomised, double-blind, crossover design; participants (n=17) received 2 capsules/d of Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011 (probiotic) alone, the probiotic with 2 capsules/d of Ca1, and probiotic with 2 capsules/d of Ca2 each for 2-week periods with 2-week baseline and washout periods. In both studies, stools were collected during the baseline, intervention and washout periods for Lactobacillus spp. quantification and qPCR analyses. Participants completed daily questionnaires of stool frequency and compliance. In Study 1, neither calcium supplement influenced viable counts of resident Lactobacillus spp., genome equivalents of lactic acid bacteria or stool frequency. In Study 2, faecal Lactobacillus spp. counts were significantly enhanced from baseline when the probiotic was administered with Ca2 (4.83±0.30, 5.79±0.31) (P=0.02), but not with Ca1 (4.98±0.31) or with the probiotic alone (5.36±0.31, 5.55±0.29) (not significant). Detection of L. helveticus R0052 and L. rhamnosus R0011 was significantly increased with all treatments, but did not differ among treatments. There were no changes in weekly stool frequency. Calcium phosphate co-administration may increase gastrointestinal survival of orally-administered Lactobacillus spp.

The infant microbiome development: mom matters

The infant microbiome plays an essential role in human health and its assembly is determined by maternal-offspring exchanges of microbiota. This process is affected by several practices, including Cesarean section (C-section), perinatal antibiotics, and formula feeding, that have been linked to increased risks of metabolic and immune diseases. Here we review recent knowledge about the impacts on infant microbiome assembly, discuss preventive and restorative strategies to ameliorate the effects of these impacts, and highlight where research is needed to advance this field and improve the health of future generations.

Differential immune-stimulatory effects of LTAs from different lactic acid bacteria via MAPK signaling pathway in RAW 264.7 cells

OBJECTIVE

Lipoteichoic acid (LTA) is an immune-stimulatory component found in the cell wall of lactic acid bacteria, which are a major group of Gram-positive bacteria known to have beneficial health effects in humans. In this study, we evaluated the stimulatory effects of LTAs isolated from different lactobacilli species with mouse macrophage RAW 264.7 cells.

METHODS

RAW 264.7 cells were stimulated with pLTA (isolated from Lactobacillus plantarum K8), rLTA (isolated from Lactobacillus rhamnosus), dLTA (isolated from Lactobacillus delbreukii), and sLTA (isolated from Lactobacillus sakei K101). Tumor necrosis factor (TNF)-α and interleukin (IL)-10 production were examined by ELISA, and nitric oxide (NO) production was assayed using Griess reaction. The mRNA and protein expression levels of inducible nitric oxide synthase (iNOS) was examined by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting. Signaling molecules were also examined by Western blotting.

RESULTS

pLTA and rLTA moderately induced TNF-α, IL-10, and NO production compared with stimulation of RAW 264.7 cells with dLTA and sLTA. Similar results were obtained for the mRNA and protein expression levels of iNOS. Western blot analysis showed that treatment of cells with pLTA or rLTA resulted in minimal phosphorylation of ERK, JNK and p38 MAPK while, dLTA and sLTA were strong activators of MAPK signaling. In addition, the glycolipid structure of LTAs was found to be composed of different fatty acid chain groups and lengths. Taken together, these results suggest that the differential immuno-stimulatory effects of LTAs isolated from different lactobacillus species may be related to their different ability to activate the MAPK signaling pathway, which are modulated by a unique glycolipid structure of LTA.

Effects of probiotic yogurt consumption on inflammatory biomarkers in patients with type 2 diabetes

Introduction: The role of inflammatory cytokines in diabetes and its complications has been shown in some studies. The purpose of this study was to compare the effect of probiotic and conventional yogurt on inflammatory markers in patients with type 2 diabetes.

Methods: Forty-four patients with type 2 diabetes were participated in this randomized, double-blind controlled clinical trial and assigned to two intervention and control groups. The subjects in the intervention group consumed 300 g/d probiotic yogurt and subjects in the control group consumed 300 g/d conventional yogurt for 8 weeks. Anthropometric indices, dietary intakes, and serum levels of glucose, HbA1c, IL-6, TNF-α and hs-CRP were evaluated at the beginning and end of the intervention.

Results: For anthropometric indices and dietary intakes, no significant differences were seen within and between groups post intervention (p> 0.05). The consumption of probiotic yogurt caused significant decrease in HbA1c and TNF-α levels (p= 0.032 and p= 0.040, respectively) in the intervention group.

Conclusion: It is suggested that probiotic yogurt may be used as an alternative prevention approach and treatment method to control diabetic complications.

Polyunsaturated fatty acids modify expression of TGF-β in a co-culture model ultilising human colorectal cells and human peripheral blood mononuclear cells exposed to Lactobacillus gasseri, Escherichia coli and Staphylococcus aureus

Commensal bacteria and polyunsaturated fatty acids (PUFAs) have both been shown independently to modulate immune responses. This study tested the hypothesis that the different colonic immunomodulatory responses to commensal (Lactobacillus gasseri) and pathogenic bacteria (Escherichia coli and Staphylococcus aureus) may be modified by PUFAs. Experiments used a Transwell system combining the colorectal cell line HT29, or its mucous secreting sub-clone HT29-MTX, with peripheral blood mononuclear cells to analyse immunomodulatory signalling in response to bacteria, with and without prior treatment with arachidonic acid, eicosapentaenoic acid or docosahexaenoic acid. L. gasseri increased transforming growth factor β1 (TGF-β1) mRNA and protein secretion in colonic cell lines when compared with controls, an effect that was enhanced by pre-treatment with eicosapentaenoic acid. In contrast, the Gram-negative pathogen E. coli LF82 had no significant effect on TGF-β1 protein. L. gasseri also increased IL-8 mRNA but not protein while E. coli increased both; although differences between PUFA treatments were detected, none were significantly different to controls. Colonic epithelial cells show different immunomodulatory signalling patterns in response to the commensal L. gasseri compared to E. coli and S. aureus and pre-treatment of these cells with PUFAs can modify responses. Practical applications: We have demonstrated an interaction between dietary PUFAs and epithelial cell response to both commensal and pathogenic bacteria found in the gastrointestinal tract by utilising in vitro co-culture models. The data suggest that n-3 PUFAs may provide some protection against the potentially damaging effects of pathogens. Furthermore, the beneficial effects of combining n-3 PUFAs and the commensal bacteria, and potential probiotic, L. gasseri are illustrated by the increased expression of immunoregulatory TGF-β1.

Prevention of necrotizing enterocolitis in preterm very low birth weight infants: is it feasible?

Necrotizing enterocolitis (NEC) is still one of the most catastrophic intestinal emergencies in preterm very low-birth weight infants. Primary prevention of NEC should be the priority, since NEC frequently progresses from nonspecific signs, to extensive necrosis within a matter of hours with medical or surgical treatment, making successful treatment and secondary prevention difficult to achieve. Currently available strategies for primary prevention of NEC include antenatal glucocorticosteroids, breast milk feeding, cautious feeding strategy, fluid restriction and probiotics. Nonetheless, based on current research evidence, mixed flora probiotics, and/or breast milk feeding, would appear to be the most effective feasible methods in the prevention of NEC at present.

Infection with feline immunodeficiency virus alters intestinal epithelial transport and mucosal immune responses to probiotics

HIV infection is associated with intestinal mucosal dysfunction and probiotics offer the therapeutic potential to enhance the mucosal barrier in HIV+ patients. To evaluate the response of immunocompromised hosts to probiotics, we orally administered Lactobacillus acidophilus to cats with chronic feline immunodeficiency virus (FIV) infection. FIV infection significantly affected transcellular, but not paracellular, transport of small molecules across the intestinal epithelium. Additionally, probiotic treatment of FIV+ cats resulted in changes in cytokine release and mucosal leukocyte percentages that were not paralleled in FIV- cats. These results suggest a novel role for FIV in upregulating transcellular transport across the gastrointestinal epithelial barrier and demonstrate the potential therapeutic use of probiotic bacteria to restore intestinal homeostasis.

In vitro cell and tissue models for studying host-microbe interactions: a review

Ideally, cell models should resemble the in vivo conditions; however, in most in vitro experimental models, epithelial cells are cultivated as monolayers, in which the establishment of functional epithelial features is not achieved. To overcome this problem, co-culture experiments with probiotics, dendritic cells and intestinal epithelial cells and three-dimensional models attempt to reconcile the complex and dynamic interactions that exist in vivo between the intestinal epithelium and bacteria on the luminal side and between the epithelium and the underlying immune system on the basolateral side. Additional models include tissue explants, bioreactors and organoids. The present review details the in vitro models used to study host-microbe interactions and explores the new tools that may help in understanding the molecular mechanisms of these interactions.

Lactobacillus acidophilus could modulate the immune response against breast cancer in murine model

Cancer immune-therapy is an interesting avenue of studying the effects of deviating immune system responses to achieve the desired result. Lactobacilli are inhabitants of the GI tract which have shown beneficial health effects on various ailments including malignancies. Their mechanisms of action comprise a very intense area of research. In this study we evaluated the immunomodulatory effects of Lactobacillus acidophilus in in vivo model of breast cancer. Lactobacillus acidophilus (L.a) was isolated from traditional home-made yogurt and also from neonatal stool by aerobic overnight culture at 37°C in MRS broth. Delayed Type Hypersensitivity (DTH) assay was performed to find the best immunostimulant dose. 4T1 tumour bearing mice were treated with 2 × 10(8) cfu of isolated L. acidophilus and 20 mg/kg Cyclophosphamide for 15 consecutive days. Tumour volume was measured using a digital vernier calliper. Lymphocyte proliferation was done using MTT proliferation assay. Production of IFNγ, IL-4 and TGF-β from cultured Splenocytes was assessed in the presence of purified tumour antigen. According to results administration of L.a induced a significant decrease in tumour growth pattern (P value = 0.00). Significant alterations in splenocyte production of IFN-γ, IL-4 and TGf-β (P values < 0.05) and also lymphocyte proliferation in L.a treated animals was evident (P value < 0.05). This study indicated that oral administration of L.a is able to alter the cytokine production in tumour bearing mice into a Th1 protective pattern, favourable to anti tumour immunity. Reduced tumour growth rate and increased lymphocyte proliferation are also thus supportive. Further studies are required to elucidate the exact mechanism by which local actions of probiotics affect the systemic immune responses against transformed cells.

Necrotizing enterocolitis: old problem with new hope

The incidence of necrotizing enterocolitis (NEC) and mortality rate associated with this disease are not decreasing despite more than three decades of intensive research investigation and advances in neonatal intensive care. Although the etiology of NEC is not clearly elucidated, the most accepted hypothesis at present is that enteral feeding in the presence of intestinal hypoxia-ischemia-reperfusion, and colonization with pathogens provokes an inappropriately accentuated inflammatory response by the immature intestinal epithelial cells of the preterm neonate. However, delayed colonization of commensal flora with dysbiotic flora with a predominance of pathologic microorganisms plays a fundamental role in the pathogenesis of NEC. Recent studies have further identified that NEC infants have less diverse flora compared to age-matched controls without NEC. Increased gastric residual volume may be an early sign of NEC. An absolute neutrophil count of <1.5 × 10(9)/L and platelets below 100 × 10(9)/L are associated with an increased risk for mortality and gastrointestinal morbidity. Nonspecific supportive medical management should be initiated promptly. Sudden changes in vital signs such as tachycardia or impending shock may indicate perforation. A recent meta-analysis investigating using probiotics for prevention of NEC with a total of 2176 preterm very low birth weight infants found a success rate of just 1/25. Careful monitoring of the residual volume, and of serious changes in hemograms and vital signs may help in early diagnosis and prediction of when to perform medical or early surgical intervention. In term of prevention, administration of oral probiotics containing Bifidobacterium and Lactobacillus is a simple and safe method that attempts to early establish of commensal flora balance to inhibit pathogenic flora and an inflammatory response.

A comprehensive post-market review of studies on a probiotic product containing Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011

The probiotic preparation Lacidofil® has been commercially available in Europe, Asia and North America since 1995. This product is a combination of two strains, Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011. The strains have been evaluated for safety, identity and mechanisms of probiotic action in vitro, in animal models and human clinical trials. The strains adhered to human epithelial cells, helped to maintain the barrier function and blocked the adhesion of a number of pathogens, allowing them to be cleared from the intestine. The strains also elicited an anti-inflammatory response by down-regulating IL-1β, IL-8 and TNF-α. In various stress models, the probiotic combination facilitated better coping and outcomes which may be through the maintenance of barrier function and suppressing inflammation. Overall, pre-clinical studies suggest a potential anti-infectious role for the strains and the combination. Clinical studies, primarily in children, have identified Lacidofil as an effective supplement for various gastrointestinal diseases such as antibiotic-associated diarrhoea and acute gastroenteritis. Recent research has also indicated that Lacidofil may be beneficial for individuals with atopic dermatitis or vaginal dysbacteriosis.

Anti-inflammatory properties of probiotic bacteria on Salmonella-induced IL-8 synthesis in enterocyte-like Caco-2 cells

Invasion of the gut by pathogenic Salmonella leads to production of IL-8 that initiates inflammatory reactions to combat the bacterium. However, its persistent production causes tissue damage and interventions that suppress IL-8 production prevent tissue damage. We hypothesised that probiotics could mediate their benefits via inhibition of IL-8 synthesis. Caco-2 cells were infected with probiotic Bifidobacterium infantis W52, Lactobacillus casei W56, Lactococcus lactis W58, Lactobacillus acidophilus W70, Bifidobacterium bifidum W23, or Lactobacillus salivarius W24 or pathogenic Salmonella enterica serovar Enteritidis 857 at 0, 0.2, 1, 2, 10, 20, 100 or 200 bacterial cells/Caco-2 cell for 1 hour. Cells were also exposed to a combination of one probiotic bacterium (200 bacterial cells/Caco-2 cell) and the graded numbers of Salmonella as either co-incubation (1 hour) or pre-incubation of the probiotic bacterium (1 hour) followed by Salmonella (1 hour). The cells recovered for 2 or 24 hours. IL-8 and Hsp70 were determined by ELISA and Western blot respectively. Both probiotics and Salmonella induced a dose- and time-dependent synthesis of IL-8 but probiotics induced far lower IL-8 levels than Salmonella. The Salmonella-induced IL-8 was significantly suppressed by B. infantis W52, L. casei W56 and L. lactis W58 at low numbers of Salmonella (0.2 to 20 bacterial cells/Caco-2 cell) and within 2 hours of recovery. The observed probiotic-mediated reduction in IL-8 secretion was transient, and lost after a few hours. In addition, these three probiotics induced a significant increase in Hsp70 expression while L. acidophilus W70, B. bifidum W23 and L. salivarius W24 induced a weak Hsp70 expression and could not suppress the Salmonella-induced IL-8 synthesis. We conclude that suppression of Salmonella-induced IL-8 synthesis by Caco-2 cells is exhibited by probiotics that induce expression of Hsp70, suggesting that the protective role of probiotics could be mediated, at least in part, via Hsp70 expression. This suppression is limited to a low number of infecting pathogenic Salmonella.

Lysozyme transgenic goats' milk positively impacts intestinal cytokine expression and morphology

In addition to its well-recognized antimicrobial properties, lysozyme can also modulate the inflammatory response. This ability may be particularly important in the gastrointestinal tract where inappropriate inflammatory reactions can damage the intestinal epithelium, leading to significant health problems. The consumption of milk from transgenic goats producing human lysozyme (hLZ) in their milk therefore has the potential to positively impact intestinal health. In order to investigate the effect of hLZ-containing milk on the inflammatory response, young pigs were fed pasteurized milk from hLZ or non-transgenic control goats and quantitative real-time PCR was performed to assess local expression of TNF-α, IL-8, and TGF-β1 in the small intestine. Histological changes were also investigated, specifically looking at villi width, length, crypt depth, and lamina propria thickness along with cell counts for intraepithelial lymphocytes and goblet cells. Significantly higher expression of anti-inflammatory cytokine TGF-β1 was seen in the ileum of pigs fed pasteurized milk containing hLZ (P = 0.0478), along with an increase in intraepithelial lymphocytes (P = 0.0255), and decrease in lamina propria thickness in the duodenum (P = 0.0001). Based on these results we conclude that consuming pasteurized milk containing hLZ does not induce an inflammatory response and improves the health of the small intestine in pigs.

Assessment of psychotropic-like properties of a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in rats and human subjects

In a previous clinical study, a probiotic formulation (PF) consisting of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 (PF) decreased stress-induced gastrointestinal discomfort. Emerging evidence of a role for gut microbiota on central nervous system functions therefore suggests that oral intake of probiotics may have beneficial consequences on mood and psychological distress. The aim of the present study was to investigate the anxiolytic-like activity of PF in rats, and its possible effects on anxiety, depression, stress and coping strategies in healthy human volunteers. In the preclinical study, rats were daily administered PF for 2 weeks and subsequently tested in the conditioned defensive burying test, a screening model for anti-anxiety agents. In the clinical trial, volunteers participated in a double-blind, placebo-controlled, randomised parallel group study with PF administered for 30 d and assessed with the Hopkins Symptom Checklist (HSCL-90), the Hospital Anxiety and Depression Scale (HADS), the Perceived Stress Scale, the Coping Checklist (CCL) and 24 h urinary free cortisol (UFC). Daily subchronic administration of PF significantly reduced anxiety-like behaviour in rats (P < 0·05) and alleviated psychological distress in volunteers, as measured particularly by the HSCL-90 scale (global severity index, P < 0·05; somatisation, P < 0·05; depression, P < 0·05; and anger-hostility, P < 0·05), the HADS (HADS global score, P < 0·05; and HADS-anxiety, P < 0·06), and by the CCL (problem solving, P < 0·05) and the UFC level (P < 0·05). L. helveticus R0052 and B. longum R0175 taken in combination display anxiolytic-like activity in rats and beneficial psychological effects in healthy human volunteers.

Microbial products from probiotic bacteria inhibit Salmonella enteritidis 857-induced IL-8 synthesis in Caco-2 cells

Oral administration of Lactobacillus spp. as probiotics is gaining importance in the treatment of intestinal inflammations. However, their mechanism of action is unknown. We investigated whether nonspecific binding Lactobacillus casei Shirota (LcS) and mannose-specific Lactobacillus plantarum 299v (Lp) and their spent culture supernatant (SCS) affect Salmonella enteritidis 857 (Se) growth, IL-8 and Hsp70 syntheses. In one set of experiments human enterocyte-like Caco-2 cells were infected with LcS, Lp or Se at 1-500 bacteria per cell for 1 h. In another set, cells were exposed to Se (0-200 per cell, 1 h) after exposure to lactobacilli (LB) (500 per cell, 30 min) or by co-incubation of Se and LB (1 h). The third set of experiments involved exposure of cells for 1 h to SCS or Se (100 per cell) pretreated (1 h) in SCS. The effect of LB SCS on Se growth was evaluated by agar plate diffusion test. IL-8 and Hsp70 were assessed over 2-24 h using ELISA and Western blotting, respectively. Neither LcS nor Lp affected the Se growth and IL-8 production. In addition, they did not induce Hsp70 expression by Caco-2 cells. Instead, their SCS inhibited the Se growth and IL-8 production and induced the expression of Hsp70 by both crypt- and villus-like cells. The beneficial effect of Lactobacillus spp. to the intestinal inflammations might be associated with a decrease in IL-8 levels. This effect could be mediated, at least in part, via a secreted antimicrobial product(s) either directly against the pathogens or indirectly through the synthesis of Hsp70.

Lactobacilli inhibit Shigella dysenteriae 1 induced pro-inflammatory response and cytotoxicity in host cells via impediment of Shigella-host interactions

OBJECTIVE

Shigella dysenteriae Type 1 dysentery is a major cause of morbidity and mortality in children from less developed and developing countries. The present study explores the hypothesis that lactobacilli protect the host cell during S. dysenteriae Type 1 infection and its mechanism of action.

METHODS

Caco-2 cells incubated for 1h with Lactobacillus rhamnosus or Lactobacillus acidophilus at the multiplicity of infection of 100, either alone or in combination followed by addition of Shigella at the same multiplicity of infection for 5h served as treatment groups. Cells incubated with Shigella without lactobacilli addition served as infected cells. At the end of experimental period, cells were processed suitably to enumerate adherent and internalized Shigella. Reverse transcription-polymerase chain reaction was performed to assess mRNA expression of interleukin-8 and tumour necrosis factor-alpha. Immunoblot for heat shock protein-70 and cytotoxicity assay were performed.

RESULTS

Pretreatment with the combination of lactobacilli significantly (p<0.05) prevented adherence and internalization of Shigella coupled with reduced expression of tumour necrosis factor-alpha and interleukin-8 in host cells.

CONCLUSION

L. rhamnosus and L. acidophilus, synergistically offered better protection during S. dysenteriae Type 1 infection by efficiently inhibiting adherence and internalization of Shigella coupled with inhibition of pro-inflammatory response.

Lactobacillus helveticus and Bifidobacterium longum taken in combination reduce the apoptosis propensity in the limbic system after myocardial infarction in a rat model

Myocardial infarction (MI) stimulates the release of pro-inflammatory substances that induce apoptosis in the limbic system. Pro-inflammatory cytokines are considered as the root cause of apoptosis, although the mechanism is not fully explained and/or understood at this time. In addition, depression may induce gastrointestinal perturbations that maintain the elevated levels of pro-inflammatory cytokines. It has been shown that some specific probiotic formulations may reduce gastrointestinal problems induced by stress and the pro/anti-inflammatory cytokine ratio. Therefore, we hypothesised that probiotics, when given prophylactically, may diminish the apoptosis propensity in the limbic system following a MI. Male adult Sprague–Dawley rats were given probiotics (Lactobacillus helveticus and Bifidobacterium longum in combination) or placebo in their drinking-water for four consecutive weeks. A MI was then induced in the rats by occluding the left anterior coronary artery for 40 min. Rats were killed following a 72 h reperfusion period. Infarct size was not different in the two groups. Bax/Bcl-2 (pro-apoptotic/anti-apoptotic) ratio and caspase-3 (pro-apoptotic) activity were reduced in the amygdala (lateral and medial), as well as in the dentate gyrus in the probiotics group when compared with the placebo. Akt activity (anti-apoptotic) was increased in these same three regions. No significant difference was observed in Ca1 and Ca3 for the different markers measured. In conclusion, the probiotics L. helveticus and B. longum, given in combination as preventive therapy, reduced the predisposition of apoptosis found in different cerebral regions following a MI.