Probiotic stool secretory immunoglobulin A modulation in children with gastroenteritis: a randomized clinical trial

Investigating the potential immunomodulatory effects of commercial oral probiotic supplements on equine gastrointestinal tract barrier function

Background

Oral probiotic dietary supplements are widely used in veterinary medicine, including in horses. It is hypothesized that the presence of probiotic strains can both modulate the intestinal microbiota and affect mucosal immunity parameters. Such a study has not yet been conducted in horses.

Methods

This study involved 12 healthy horses, which were randomly divided into a control group and a group that received a commercial oral probiotic formula containing Lactobacillus rhamnosus, Pedioccus acidilactici or Enterococcus faecium for 84 days. Fecal samples were collected from all horses on day 0 (D0), 28 days after starting the probiotic (D28), 56 days (D56), 84 days (D84) and 28 days after stopping the probiotic (DX) treatment. The samples were subjected to microbiome analysis via next-generation sequencing of hypervariable regions V3-V4 and V7-V9 of the 16S rRNA gene for analysis of short-chain fatty acids via HPLC analysis and fecal secretory immunoglobulin A (SIgA) quantification via ELISA.

Results

Microbiome analysis revealed no significant differences in either alpha or beta diversity parameters between the groups. No probiotic strains were detected in the samples. Significant changes were detected in three taxa: the family Bacteroidales RF16 group, the genus Erysipelotrichaceae UCG-004, and the genus Fibrobacter during the study in both groups. In all the cases, there was a gradual decrease in relative abundance over time. The concentrations of SCFAs, specifically acetic and propionic acids, significantly increased over time in both groups according to the generalized linear mixed effects (GLME) model. There were no significant differences in fecal SIgA secretion.

Conclusion

The present study revealed no effect of the use of a commercial probiotic dietary supplement on either mucosal immunity or the composition of the intestinal microbiota.

Advances in characterization of probiotics and challenges in industrial application

An unbalanced diet and poor lifestyle are common reasons for numerous health complications in humans. Probiotics are known to provide substantial benefits to human health by producing several bioactive compounds, vitamins, short-chain fatty acids and short peptides. Diets that contain probiotics are limited to curd, yoghurt, kefir, kimchi, etc. However, exploring the identification of more potential probiotics and enhancing their commercial application to improve the nutritional quality would be a significant step to utilizing the maximum benefits. The complex evolution patterns among the probiotics are the hurdles in their characterization and adequate application in the industries and dairy products. This article has mainly discussed the molecular methods of characterization that are based on the analysis of ribosomal RNA, whole genome, and protein markers and profiles. It also has critically emphasized the emerging challenges in industrial applications of probiotics.

The Efficacy of Probiotics as Antiviral Agents for the Treatment of Rotavirus Gastrointestinal Infections in Children: An Updated Overview of Literature

Enteric viruses, including the rotavirus, norovirus, and adenoviruses, are the most common cause of acute gastroenteritis. The rotavirus disease is especially prevalent among children, and studies over the past decade have revealed complex interactions between rotaviruses and the gut microbiota. One way to treat and prevent dysbiosis is the use of probiotics as an antiviral agent. This review focuses on the latest scientific evidence on the antiviral properties of probiotics against rotavirus gastroenteric infections in children. A total of 19 studies exhibited a statistically significant antiviral effect of probiotics. The main probiotics that were effective were Saccharomyces cerevisiae var. boulardii, Lacticaseibacillus rhamnosus GG, and various multi-strain probiotics. The underlying mechanism of the probiotics against rotavirus gastroenteric infections in children included immune enhancement and modulation of intestinal microbiota leading to shortening of diarrhoea. However, several clinical studies also found no significant difference in the probiotic group compared to the placebo group even though well-known strains were used, thus showing the importance of correct dosage, duration of treatment, quality of probiotics and the possible influence of other factors, such as the production process of probiotics and the influence of immunisation on the effect of probiotics. Therefore, more robust, well-designed clinical studies addressing all factors are warranted.

Pathogen-Specific Effects of Probiotics in Children With Acute Gastroenteritis Seeking Emergency Care: A Randomized Trial

BACKGROUND

It is unknown if probiotics exert pathogen-specific effects in children with diarrhea secondary to acute gastroenteritis.

METHODS

Analysis of patient-level data from 2 multicenter randomized, placebo controlled trials conducted in pediatric emergency departments in Canada and the United States. Participants were 3-48 months with >3 diarrheal episodes in the preceding 24 hours and were symptomatic for <72 hours and <7 days in the Canadian and US studies, respectively. Participants received either placebo or a probiotic preparation (Canada-Lactobacillus rhamnosus R0011/Lactobacillus helveticus R0052; US-L. rhamnosus GG). The primary outcome was post-intervention moderate-to-severe disease (ie, ≥9 on the Modified Vesikari Scale [MVS] score).

RESULTS

Pathogens were identified in specimens from 59.3% of children (928/1565). No pathogen groups were less likely to experience an MVS score ≥9 based on treatment allocation (test for interaction = 0.35). No differences between groups were identified for adenovirus (adjusted relative risk [aRR]: 1.42; 95% confidence interval [CI]: .62, 3.23), norovirus (aRR: 0.98; 95% CI: .56, 1.74), rotavirus (aRR: 0.86; 95% CI: .43, 1.71) or bacteria (aRR: 1.19; 95% CI: .41, 3.43). At pathogen-group and among individual pathogens there were no differences in diarrhea duration or the total number of diarrheal stools between treatment groups, regardless of intervention allocation or among probiotic sub-groups. Among adenovirus-infected children, those administered the L. rhamnosus R0011/L. helveticus R0052 product experienced fewer diarrheal episodes (aRR: 0.65; 95% CI: .47, .90).

CONCLUSIONS

Neither probiotic product resulted in less severe disease compared to placebo across a range of the most common etiologic pathogens. The preponderance of evidence does not support the notion that there are pathogen specific benefits associated with probiotic use in children with acute gastroenteritis.

CLINICAL TRIALS REGISTRATION

NCT01773967 and NCT01853124.

Intestinal Microbial Composition of Children in a Randomized Controlled Trial of Probiotics to Treat Acute Gastroenteritis

Compositional analysis of the intestinal microbiome in pre-schoolers is understudied. Effects of probiotics on the gut microbiota were evaluated in children under 4-years-old presenting to an emergency department with acute gastroenteritis. Included were 70 study participants (n=32 placebo, n=38 probiotics) with stool specimens at baseline (day 0), day 5, and after a washout period (day 28). Microbiota composition and deduced functions were profiled using 16S ribosomal RNA sequencing and predictive metagenomics, respectively. Probiotics were detected at day 5 of administration but otherwise had no discernable effects, whereas detection of bacterial infection (P<0.001) and participant age (P<0.001) had the largest effects on microbiota composition, microbial diversity, and deduced bacterial functions. Participants under 1 year had lower bacterial diversity than older aged pre-schoolers; compositional changes of individual bacterial taxa were associated with maturation of the gut microbiota. Advances in age were associated with differences in gut microbiota composition and deduced microbial functions, which have the potential to impact health later in life.