Efficacy and dose response of Lactiplantibacillus plantarum in diarrhea-predominant irritable bowel syndrome

Bacillus coagulans alleviates intestinal barrier injury induced by Klebsiella pneumoniae in rabbits by regulating the TLR4/MyD88/NF-κB signalling pathway

Probiotics effectively alleviate host diarrhoea, but the specific mechanism is not clear. Therefore, we explored the protective mechanism of Bacillus coagulans (BC) on intestinal barrier injury induced by Klebsiella pneumoniae (K. pneumoniae) in rabbits by HE, immunofluorescence and 16S rRNA. The results showed that BC pretreatment alleviated the changes in average daily gain, average daily feed intake and FCR caused by K. pneumoniae in rabbits. Moreover, BC alleviated the inflammatory cell infiltration, intestinal villus reduction, crypt deepening and goblet cell reduction caused by K. pneumoniae in rabbits. Further research revealed that BC improved the intestinal barrier by improving the mechanical barrier, chemical barrier, immune barrier and microbial barrier. Specifically, BC improved the intestinal mechanical barrier by improving the intestinal structure, increasing the protein expression of PCNA, increasing the number of goblet cells, and altering the expression of occludin, claudin-1 and ZO-1. BC improved the intestinal chemical barrier by regulating the expression of MUC1 and MUC2 and inhibited the TLR4/MyD88/NF-κB signalling pathway by altering the expression levels of the inflammatory factors IL-1β, IL-6 and TNF-α, thus optimizing the intestinal immune barrier. In addition, adding BC to the diet improved the intestinal microbial barrier of rabbits by reducing the abundance of harmful bacteria and increasing the abundance of beneficial bacteria. In summary, BC protects against K. pneumoniae-induced intestinal barrier damage by improving intestinal morphology, mitigating the inflammatory response and regulating the microbial composition. Among the pretreatments, the pretreatment effect of 1 × 106 CFU/g was the best. This study provides a theoretical basis for the use of BC to prevent and treat diarrhoea caused by K. pneumoniae in rabbits.

Dietary Modulation of the Immune System

Recent insights into the influence of nutrition on immune system components have driven the development of dietary strategies targeting the prevention and management of major metabolic-inflammatory diseases. This review summarizes the bidirectional relationship between nutrition and immunocompetence, beginning with an overview of immune system components and their functions. It examines the effects of nutritional status, dietary patterns, and food bioactives on systemic inflammation, immune cell populations, and lymphoid tissues, as well as their associations with infectious and chronic disease pathogenesis. The mechanisms by which key nutrients influence immune constituents are delineated, focusing on vitamins A, D, E, C, and B, as well as minerals including zinc, iron, and selenium. Also highlighted are the immunomodulatory effects of polyunsaturated fatty acids as well as bioactive phenolic compounds and probiotics, given their expanding relevance. Each section addresses the implications of nutritional and nutraceutical interventions involving these nutrients within the broader context of major infectious, metabolic, and inflammatory diseases. This review further underscores that, while targeted nutrient supplementation can effectively restore immune function to optimal levels, caution is necessary in certain cases, as it may increase morbidity in specific diseases. In other instances, dietary counseling should be integrated to ensure that therapeutic goals are achieved safely and effectively.

A Review of Pharmacologic and Non-Pharmacologic Therapies in the Management of Irritable Bowel Syndrome: Current Recommendations and Evidence

Irritable bowel syndrome (IBS) is a highly prevalent and debilitating disorder of gut-brain interaction (DGBI) affecting millions globally. It imposes a significant burden on healthcare systems and is a leading cause of workplace absenteeism. IBS is classified into several subtypes based on predominant presenting symptoms, including IBS with constipation (IBS-C) and IBS with diarrhea (IBS-D), with each requiring targeted approaches to treatment. Some treatments, such as psychotherapy, dietary intervention, and medications like tricyclic antidepressants, are nonspecific and recommended for managing IBS symptoms across all subtypes. In contrast, therapies like secretagogues for IBS-C and eluxadoline or rifaximin for IBS-D are subtype-specific. However, many IBS treatments carry conditional recommendations and are based on low-certainty evidence, emphasizing the need for further research to expand the available treatment options. This review compares the latest IBS management guidelines from the American Gastroenterological Association (AGA), American College of Gastroenterology (ACG), British Society of Gastroenterology (BSG), and European Society for Neurogastroenterology and Motility (ESNM). Pharmacologic and non-pharmacologic therapies, including established and emerging interventions, will be explored to provide a comprehensive guide to management.

Probiotics and Prebiotics for the Treatment of Irritable Bowel Syndrome-A Narrative Review

Background/Objectives: Gastrointestinal functional disorders (GFDs), including irritable bowel syndrome (IBS), are imbalances in the gut-brain axis characterized by persistence of symptoms in the abdominal area. Probiotics are live microorganisms that provide benefits to the health of their hosts when administered in adequate amounts, while prebiotics are a substrate that is selectively used by host microorganisms. This narrative review aimed to evaluate the effectiveness of prebiotics and probiotics mostly in irritable bowel syndrome, particularly on issues such as the interaction between these products and the gut microbiota, the duration of supplementation and long-term effects, the definition of ideal dosages, and the regulation and quality control of these products. Methods: A bibliographic search was carried out in indexed databases and articles published within 10 years before the beginning of the study and publications in English language, which investigated the specific theme of the study were considered. Papers dealing with topics not covered by the research questions, or presenting errors related with the wrong population or the wrong methods, as well as experimental studies and case reviews were excluded. Fifty-five articles were selected, initially in isolation by the authors and, afterward, under consensus. Results: It was possible to observe the effectiveness mainly of probiotics, in improving specific symptoms of the respective disorder; however, the available data remain unclear due to limitations concerning samples and methods of the studies evaluated. Conclusions: Despite evidence suggestive of therapeutic efficacy, additional multicenter randomized controlled trials (RCTs) with better defined protocols are still necessary to fill in the gaps in this subject, define measures to ensure the safe administration of these products, and confirm their therapeutic potential.

Complete genome sequence and anti-obesity potential of Lactiplantibacillus plantarum HOM2217 in 3T3-L1 cells and high-fat diet-fed rats

The global prevalence of obesity is rising year by year, which has become a public health problem worldwide. Many animal and clinical studies have shown that Lactiplantibacillus plantarum is considered an ideal probiotic and potential supplement for the treatment of obesity. In this study, we aimed to complete the genome sequence of L. plantarum HOM2217, which was isolated from human milk, and study its physiological characteristics and anti-obesity effects in 3T3-L1 cells and rats fed a high-fat diet (HFD) to determine its potential as a starter for functional food products. Whole-genome analysis demonstrated that HOM2217 contained a single circular chromosome of 3,267,529 bp with a GC content of 44.5% and one plasmid (62,350 bp) with a GC content of 38.5%. Compared to the reference strains, HOM2217 demonstrated superior tolerance to gastrointestinal conditions, higher adhesion to intestinal epithelial cell lines, potent antimicrobial activity against Enterobacter cloacae ATCC 13047, and effective cholesterol removal ability in vitro. Treatment with heat-killed HOM2217 significantly reduced lipid accumulation and intracellular triglyceride production in 3T3-L1 adipocytes. Daily treatment of HFD-fed rats with HOM2217 for 7 weeks decreased body weight, body weight gain, and body fat without changes in food intake. HOM2217 also significantly increased the serum high-density lipoprotein cholesterol (HDL-C) level, decreased the serum tumor necrosis factor (TNF-α) and increased short-chain fatty acid (SCFA) (formic acid, acetic acid, and butyric acid) levels in the cecum. Thus, HOM2217 could potentially prevent obesity in rats by inhibiting inflammatory responses and regulating lipid metabolism and SCFAs expression. Therefore, HOM2217 has potential as an alternative treatment for obesity.

He who controls Clostridia and Bacteroidia controls the gut microbiome: The concept of targeted probiotics to restore the balance of keystone taxa in irritable bowel syndrome

This article describes the concept of probiotics for patients with irritable bowel syndrome to target functionally active bacteria predominantly belonging to the Clostridia and Bacteroidia, which play a key role in maintaining the balance of the gut microbiota.

Unlocking the potential of probiotic administration in caries management: a systematic review

BACKGROUND

The use of prebiotics and/or probiotic bacteria with the potential to modulate the oral ecosystem may play an important role in the prevention and management of dental caries. To assess the evidence of the potential of pre/probiotics both in the prevention and treatment of dental caries, we focused on the PICO question "In individuals with caries, after probiotic administration, is there an improvement in outcomes directly related to caries risk and development?".

METHODS

An extensive systematic search was conducted in electronic databases PubMed, Web of Science, Scopus and Cochrane, to identify articles with relevant data. This systematic review included trials performed in Humans; published in English; including the observation of patients with caries, with clear indication of the probiotic used and measuring the outcomes directly involved with the cariogenic process, including the quantification of bacteria with cariogenic potential. To evaluate the methodological quality of the studies, the critical assessment tool from the Joanna Briggs Institute was used.

RESULTS

Eight hundred and fifty articles, potentially relevant, were identified. Following PRISMA guidelines 14 articles were included in this systematic review. Outcomes such as reduction of cariogenic microorganism counts, salivary pH, buffer capacity, and caries activity were assessed. The probiotic most often referred with beneficial results in dental caries outcomes is Lacticaseibacillus rhamnosus. Regarding the most used administration vehicle, in studies with positive effects on the caries management, probiotic supplemented milk could be considered the best administration vehicle.

CONCLUSIONS

Evidence suggests a beneficial effect of probiotic supplemented milk (Lacticaseibacillus rhamnosus) as an adjuvant for caries prevention and management. However, comparable evidence is scarce and better designed and comparable studies are needed.