Search Results (282)

As the critical component of the gastrointestinal tract, which lives in trillions of gut microorganisms, in a healthy state, the host interacts with the gut microbiota and is symbiotic. The species Limosilactobacillus reuteri, Ligilactobacillus salivarius, and Lactobacillus johnsonii are indigenous gut commensal bacteria that are mainly found in the digestive tracts. These three bacteria possess a variety of characteristics that reflect their ability to adapt to the gastrointestinal environment. Herein, we summarize the current progress of research on the probiotic properties of these strains in terms of their ability to protect against harmful pathogens, maintain intestinal health, and improve disease outcomes. These bacteria can impact the intestinal barrier function and enhance intestinal immunity through various mechanisms, such as upregulating the tight-junction protein expression and mucin secretion of intestinal epithelial cells, adjusting and balancing the gut microbiota, and blocking pro-inflammatory cytokine production. They have been shown to ameliorate intestinal inflammation in animal models and provide protective effects against various healthy issues in humans, including diarrhea, constipation, colorectal cancer, obesity, and liver diseases. However, the detailed mechanisms of certain strains remain unclear. Full article

Background: Early childhood caries is closely associated with oral dysbiosis and the proliferation of Streptococcus mutans. Oral probiotics, particularly Lactobacillus reuteri and Lactobacillus rhamnosus, have been proposed as ecological modulators capable of reducing cariogenic microorganisms. Objective: To evaluate the efficacy of orally administered L. reuteri and L. rhamnosus in reducing salivary S. mutans levels in children aged 6 months to 12 years through a systematic review and meta-analysis. Methods: This review followed the PRISMA 2020 guidelines and was prospectively registered in PROSPERO (CRD420251086304). Searches were conducted in MEDLINE/PubMed, CENTRAL, Embase, Scopus and LILACS without language or date restrictions. Randomized controlled trials administering the target probiotic strains for ≥30 days were included. Risk of bias was assessed using RoB 2, and certainty of evidence using GRADE. Random-effects meta-analyses were performed for continuous and dichotomous outcomes. Results: Six randomized controlled trials were included (N = 1362). Only two trials reported continuous outcomes in comparable log₁₀ CFU/mL format and could therefore be pooled for the continuous meta-analysis. This analysis showed a significant reduction in salivary S. mutans levels (MD = −0.65 log₁₀ CFU/mL; 95% CI: −0.97 to −0.34; p < 0.0001; I² = 19%), although the pooled estimate was largely driven by one study and should be interpreted cautiously. Four trials contributed to the dichotomous meta-analysis, which showed a non-significant trend toward risk reduction (OR = 0.73; 95% CI: 0.51–1.06; p = 0.10; I² = 35%). Short-term interventions using high oral-retention formulations demonstrated the most consistent microbiological effects. Conclusions: Oral probiotics may significantly reduce salivary S. mutans in the short-term, especially when delivered through slow-dissolving formulations. However, their effects vary according to strain, vehicle, and intervention duration. Larger, standardized, and longer-term clinical trials are needed to determine the sustainability and clinical relevance of these effects. Full article

The close connections between the intestine and distal systems, known as axes, are a growing focus of scientific research; however, the gut–vascular axis, particularly as a target of microbial metabolites, remains underexplored. In this study, three supernatants derived from probiotic formulations composed of Lactobacillus and Bifidobacterium strains (MIX-1, MIX-2, and MIX-3) were evaluated in counteracting vascular alterations associated with dysbiosis. Human aortic smooth muscle (HASMCs) and endothelial (HAECs) cells were exposed to pro-oxidative (H₂O₂) and pro-inflammatory (TMAO) stimuli. Concentrations up to 5–10% (v/v) were tolerated in both cell lines, with MIX-1 and MIX-3 showing the greatest protective efficacy. These formulations exerted antioxidant effects by reducing H₂O₂-induced ROS production and cell viability loss, and anti-inflammatory effects by limiting TMAO-induced IL-1β release. MIX-1 also attenuated TMAO-induced IL-6 release. Further analyses indicated a partial involvement of the SIRT1-pathway in its vascular antioxidant effects. Chromatographic profiling revealed comparable qualitative metabolites among the probiotic supernatants, while quantitative differences were observed, with higher lactate levels in MIX-1 and MIX-3 compared to MIX-2. Finally, we have determined that Limosilactobacillus reuteri-PBS072 is mainly responsible for the antioxidant effect of MIX-1 and MIX-3. Overall, these findings highlight the potential of probiotic-derived metabolites in modulating the gut–vascular axis and promoting vascular protection. Full article

Dental caries is a multifactorial chronic infectious disease that impacts healthcare costs globally, caused by alterations of the plaque microbiome and proliferation of cariogenic Streptococcus mutans. Treatments targeting S. mutans, such as alternative strategies using probiotics, might be effective in preventing the development of dental caries. In this study, the probiotic formulation of Lactobacillus reuteri SGL01, vitamin C, and acerola was tested against S. mutans DSM20523. Antimicrobial activity was assessed by deferred antagonism and spot-on-lawn assays for L. reuteri SGL01. MIC and MBC of L. reuteri SGL01 cell-free supernatant (CFS), vitamin C, and acerola were determined with the microdilution method. Time–kill assays determined the bactericidal kinetics for each compound. The checkerboard method was used to evaluate the potential synergistic activity of CFS–vitamin C or CFS–acerola at scalar dilutions from 1 to 8X MIC. Lastly, antibiofilm activity was tested for each compound. Antimicrobial activity of L. reuteri SGL01 was first assessed by classic methods. MIC and MBC values differed for one dilution for all compounds, with values of 25% and 50% for CFS, 9.3 mg/mL and 18.7 mg/mL for vitamin C, and 18.7 mg/mL and 37.5 mg/mL for acerola, respectively. Moreover, time–kill assays confirmed the bactericidal activity at different timepoints: 4 h for CFS, 6 h for vitamin C, and 24 h for acerola. The fractional inhibitory concentration index (FICI) showed indifference for all combinations, and for associations tested at 2, 4, and 8XMIC. S. mutans biofilm production was impaired for all components, with stronger activity by vitamin C and acerola at lower concentrations. The probiotic formulation containing L. reuteri SGl01, vitamin C, and acerola extract exerts a bactericidal effect, especially strong for the CFS, as well as antibiofilm activity. Thus, the combination of these three components could be advantageous for their complementary effects, with use as a novel treatment against the development of dental caries by S. mutans. Full article

The immunoregulatory effects of probiotics have been widely studied, particularly in maintaining immune balance. Conventional in vitro functional screening of probiotics relies on fresh donor-derived primary immune cells, which often exhibit significant inter-individual and temporal variability, limiting reproducibility and interpretation. As an alternative, human-induced pluripotent stem cell (iPSC)-derived dendritic cells were co-cultured with five probiotic strains in the current study to evaluate their immunomodulatory interactions. To assess whether cytokines produced by probiotic-stimulated dendritic cells can influence T cell differentiation, human CD4⁺ T cells were exposed to the conditioned medium derived from co-cultures. Enzyme-linked immunosorbent assay results demonstrated that iPSC-derived dendritic cells secreted cytokines at distinct concentrations in response to different probiotic strains, suggesting that these cells can distinguish between different microbial stimuli, and supporting their use in functional probiotic screening. Among the five strains tested, Lactiplantibacillus plantarum LPA-56, Limosilactobacillus reuteri RU-23, and Lactobacillus fermentum Fem-99 induced cytokine production levels that promoted the differentiation of the human CD4⁺ T cells into regulatory T cells. These findings demonstrate that iPSC-derived dendritic cells have immunomodulatory potential, are reliable for in vitro screening of probiotics, and offer a promising strategy for selecting potent immunoregulatory probiotic candidates. Full article

Avian pathogenic Escherichia coli (E. coli) impairs poultry production and causes substantial economic losses. This study investigated the effects of Lactobacillus reuteri postbiotics (LR) on growth performance and intestinal health of broiler chickens challenged with E. coli. A total of 180 one-day-old Arbor Acres+ broilers were allocated into three groups (six replicates per group and 10 chicks each replicate): CTR, control group; E. coli-infected group, orally challenged with a mixture of E. coli O₁, O₂, and O₇₈ at a dose of 10⁹ CFU/mL; LR + E. coli-infected group, challenged with E. coli and fed a basal diet supplemented with 100 mg/kg LR. The results showed that dietary LR significantly improved the average daily gain (ADG) in the LR + E. coli group compared to the E. coli-infected group from days 1 to 18 (p < 0.05). However, no significant differences in average daily feed intake (ADFI) or feed conversion ratio (FCR) were observed among the CTR, E. coli, and LR + E. coli groups. Infection with E. coli led to lower total antioxidant capacity in jejunum and activity of total superoxide dismutase in ileum. Moreover, dietary LR significantly alleviated the down-regulation of Mucin2 and Aquaporin-3 gene expression in jejunum and ileum caused by E. coli infection and up-regulated the gene expression of Claudin-1 and Zonula occludens 1 in the ileum. In addition, dietary LR treatment led to the up-regulation of interleukin-10 mRNA transcripts in the jejunum. Further analysis demonstrated that dietary supplementation with LR reshaped the ileal flora of birds challenged with E. coli via elevating the relative abundance of Romboutsia and Bacteroidota, while reducing the abundance of Candidatus_Arthromitus and Escherichia-Shigella. In conclusion, dietary LR supplementation improved the expression of intestinal barrier and anti-inflammatory genes and reshaped the intestinal flora in E. coli-infected broilers. Full article

Oral candidiasis, mainly from Candida albicans, affects immunocompromised individuals, the elderly, and denture wearers. Probiotics offer immunomodulatory and microbiota-balancing benefits as potential antifungal alternatives. However, the comparative impact of different probiotic delivery methods remains inadequately explored. This systematic review evaluated the effectiveness of various probiotic delivery methods in reducing Candida colonization and clinical symptoms in oral candidiasis. Following PRISMA 2020 guidelines, a systematic review search across multiple databases included human clinical studies based (Medline, Web of Science, ScienceDirect, and ProQuest) on PICO criteria across all age groups. Outcomes assessed included Candida load, oral microbiota changes, symptom improvement, and disease recurrence. Of 297 articles screened, 10 met inclusion criteria. Delivery methods investigated included lozenges, capsules, yogurt, and cheese. Most studies reported reductions in Candida colony-forming units (CFUs) or prevalence, mainly for C. albicans and for non-albicans species, with probiotics such as Lactobacillus reuteri, L. rhamnosus, L. acidophilus, and Bifidobacterium strains. Some studies reported improved immunological markers, while symptom relief, especially when probiotics were combined with antifungals. Probiotics reduce Candida colonization and symptoms, with potential prolonged effects. They show promise as adjunctive therapies, but standardized, large-scale trials are needed for optimization. Full article

Avian coccidiosis is an intestinal disease caused by Eimeria spp. infection. A deeper understanding of the interaction between host gut microbiota and the Eimeria parasite is crucial for developing alternative therapies to control avian coccidiosis. Here, we used full-length sequencing of 16S ribosomal RNA amplicons to compare changes in the gut microbiota of chickens infected with Eimeria tenella, Eimeria maxima, and Eimeria necatrix, aiming to identify both species-specific and common alterations in gut microbiota at 4 and 10 days post-infection. The result revealed that infection with all three Eimeria species led to a decrease in the abundance of the microbial genera Limosilactobacillus, Streptococcus, Alistipes, Lactobacillus and Phocaeicola, while the abundance of Bacteroides, Escherichia and Ligilactobacillus increased. Escherichia and Enterococcus were most abundant in the jejunum of the E. necatrix-infected group and in the cecum of the E. tenella-infected group, whereas Megamonas abundance was highest in the E. maxima-infected group. LEfSe analysis showed that infection with all three Eimeria species significantly reduced the abundance of 13 bacterial species, including Acetilactobacillus jinshanensis, Bacteroides ndongoniae, Barnesiella viscericola, Christensenella minuta, Enterocloster clostridioformis, Gemella haemolysans_A, Granulicatella adiacens, Lawsonibacter sp000177015, Limosilactobacillus reuteri, Limosilactobacillus reuteri_D, Limosilactobacillus vaginalis_A, Limosilactobacillus caviae, Limosilactobacillus vaginalis. Infection with E. tenella significantly increased the abundance of five bacterial species, including Bacteroides fragilis, Enterococcus cecorum, Helicobacter pylori, Methylovirgula ligni, and Phocaeicola sp900066445. Infection with E. maxima significantly increased the abundance of seven bacterial species, including Clostridioides difficile, Faecalibacterium prausnitzii, Mediterraneibacter torques, Muribaculum intestinale, Mediterraneibacter massiliensis, Phascolarctobacterium faecium, and Phocaeicola plebeius. Infection with E. necatrix significantly increased the abundance of seven bacterial species, including Alistipes sp900290115, Anaerotignum faecicola, Bacteroides fragilis_A, Escherichia coli, Harryflintia acetispora, Pseudoclostridium thermosuccinogenes, and Tidjanibacter inops_A. The results showed that Eimeria infection causes significant species- and time-dependent changes in the gut microbiota of chickens. These findings enhance our understanding of coccidiosis pathogenesis and offer potential targets for developing probiotics. Full article

Chronic exposure to short-wavelength blue light induces oxidative stress, inflammation, and apoptosis in retinal tissues, contributing to vision loss. This study investigated the protective effects of Lactobacillus reuteri Y7, a human-derived probiotic, against blue light–induced retinal damage in mice. Male C57BL/6 mice were exposed to 400 lux blue light for 35 days and received either low- or high-dose Y7, lutein, or no intervention. Retinal morphology, inflammatory gene expression, gut barrier integrity, and gut microbiota composition were assessed. Low-dose Y7 promoted microbial diversity and enrichment of short-chain fatty acid–producing taxa, while high-dose Y7 favored enrichment of Akkermansia, Parasutterella, and Bacteroides, enhancing mucosal barrier function and metabolic regulation. Both doses attenuated retinal inflammation, preserved retinal layers, and improved gut barrier integrity, with high-dose Y7 matching or exceeding lutein’s protective effects. Mechanistic insights suggest a gut–retina axis whereby microbial metabolites modulate oxidative stress, inflammation, and vascular homeostasis. These findings highlight L. reuteri Y7 as a potential non-invasive strategy for retinal degeneration prevention, with efficacy comparable to dietary antioxidants. Future studies should explore long-term safety, metabolite-mediated mechanisms, and comparative efficacy with other antioxidants. Full article

The cage-free rearing of laying hens combined with probiotics promotes intestinal health. The aim of this study was to evaluate the effect of adding probiotics on the intestinal microbiota of Isa Brown laying hens raised in a cage-free system. A total of 450 Isa Brown hens, 19 weeks old, were used in a cage-free system over three 28-day cycles in a completely randomized design with five treatments and six replicates, containing 15 birds per pen. The Isa Brown hens were fed a basal ration based on corn and soybean meal; a basal ration plus a single strain of Bacillus subtilis (500 g/t); a basal ration plus a single strain, Bacillus subtilis (1000 g/t); a basal ration plus a probiotic blend (Bacillus subtilis, Enterococcus faecium, Lactobacillus acidophilus, Lactobacillus delbrueckii, Lactobacillus plantarum, Lactobacillus reuteri, Lactobacillus salivarius, Pediococcus acidilactici) at a dosage of 200 g/t; and a basal ration plus the blend at 400 g/t. From one hen per replicate, contents from the small intestine, including the duodenum, jejunum, and ileum, were collected for DNA extraction and bacterial species identification. There was an increase in Helicobacter brantae, which was quantified at 86% in the diet containing 1000 g/t of the probiotic single strain of Bacillus subtilis and 87% in the diet containing 500 g/t dosage, in comparison to the basal ration. With the probiotic blend at 200 g/t, 37% Lactobacillus crispatus and 21% Lactobacillus aviarius were observed, while the dosage of 400 g/t of the probiotic blend increased the level of Lactobacillus kitasatonis to 68% compared to the basal ration. The inclusion of 200 g/t of the probiotic blend proved to be more beneficial to the small intestinal microbiota of laying hens. Full article

Background: Many literature studies have reported the beneficial effects of probiotics on human health, but few articles have evaluated their “real effects” on the modulation of microbiota after their use. Lactobacillus reuteri (L. reuteri) is one of the most studied probiotics with the best effects on gut microbiota. Aims: The primary aim of our study was the evaluation of the intestinal colonization by L. reuteri-LMG P 27481 and its effects on the modification of the gut bacterial flora. The secondary aim was the evaluation of side effects through the validated Gastrointestinal Symptom Rating Scale (GSRS). Patients and Methods: This is an interventional, open-label study conducted on 20 healthy adults (10 men and 10 women M/F; mean age 34 ±15 years) who received a probiotic Reuterin^® LMG (L. reuteri LMG P 27481) for 28 consecutive days in drops at a concentration of 1 × 10⁹ (five drops per day). Microbiota analysis was performed at enrollment (T0), at the end of probiotic supplementation (T1) and after a 14-day follow-up period (T2). Results: In our study we observed interesting quantitative and functional variations as regards the Firmicutes/Bacterioidetes ratio, intestinal permeability, and the production of short-chain fatty acids (SCFA). This probiotic was safe and was able to improve patients’ symptoms. Conclusions: The intake of L. reuteri LMG-P 27481 in healthy subjects showed transitory variations in some functional and metabolic gut functions, especially an improvement in the barrier effect and intestinal permeability, y and an increase in SCFA. Future studies should include target populations to have a greater range for modulation of the gut microbiota. Full article

This study investigated the inhibitory effect of Lactobacillus reuteri with glycerol inoculated at different production stages of white-brined cheese (WBC) immersed in different concentrations of brine solutions under different storage temperatures as a bio-preservative against Listeria monocytogenes. Additionally, the physicochemical properties of WBC and brine solution were evaluated. A cocktail of five L. reuteri strains (~6 log CFU/g) with the addition of 100 mM glycerol was inoculated at either (1) water used to make the brine, (2) directly to the brine solution, or (3) pasteurized milk used to prepare cheese. The effect of L. reuteri against a cocktail of five L. monocytogenes strains (~5 log CFU/g) in WBC and stored in 10% or 15% brine at 4, 10, or 24 °C for 91 days was investigated. The salt content, pH, and water activity (a_w) of WBC were also evaluated. L. reuteri inoculated in brine solution reduced the numbers of L. monocytogenes by 0.7–1.4 and 0.4–1.6 log CFU/g, in WBC and brines (10–15%), respectively, stored at different storage temperatures for 91 days compared to L. monocytogenes numbers in the absence of L. reuteri (control). When L. reuteri and glycerol were added to pasteurized milk during the production of WBC, the L. monocytogenes counts decreased by 1.2–2.9 and 1.4–2.5 log CFU/g in cheese and brines, respectively. However, the addition of L. reuteri and glycerol to water used in the preparation of brines reduced L. monocytogenes by 1.2–2.6 and 1.2–2.2 log CFU/g in cheese and brines, respectively. The highest inhibitory effect of L. reuteri was observed against L. monocytogenes in both cheese and brine with 10% NaCl and high temperatures (10–24 °C). The addition of L. reuteri with glycerol has the potential to reduce the risk of L. monocytogenes without negatively affecting the physicochemical characteristics of the cheese. Full article

Background: Limosilactobacillus reuteri (L. reuteri), present in the oral and intestinal microbiota, can colonize the oral cavity through breastfeeding and dairy intake, promoting oral health by balancing the microbiota, inhibiting pathogens, and modulating immune responses. This study aimed to evaluate the preventive role and therapeutic potential of L. reuteri in pediatric oral health. Methods: A literature review was conducted using PubMed, Wiley Library, and the Cochrane Library, supplemented by manual screening, according to PRISMA guidelines and covering the period from January 2011 to 31 December 2024. Results: From 835 records identified, 12 studies met the inclusion criteria. Data shows that L. reuteri strains produce antimicrobial substances that disrupt biofilms and inhibit Streptococcus mutans and other lactobacilli, leading to increased oral pH and improved periodontal indices. The effectiveness of probiotics was found to be strain-specific and transient, with continuous intake and adequate oral hygiene enhancing their ability to colonize the oral cavity. Conclusions: Probiotics show significant potential as therapeutic interventions for controlling cariogenic bacteria and supporting gum health in children. Through mechanisms including bacterial co-aggregation, competitive exclusion, antimicrobial compound synthesis, and immune modulation, probiotics may effectively reduce the risk of tooth decay and gum disease. Their effectiveness depends on the strain, regular intake, proper dosing, good oral hygiene, and suitable delivery, which enhance oral colonization and clinical benefits. Full article

Hyperuricemia (HUA), a metabolic disorder characterized by elevated serum uric acid resulting from imbalanced production and excretion, is associated with gout and other serious health issues. This study aimed to screen out the potential probiotics with HUA-alleviating properties among 20 Lactobacillus strains. The results showed that L. reuteri Urob-7 exhibited the highest degradation rates for inosine and guanosine (82.10% and 88.78%, respectively) and strong xanthine oxidase (XOD) inhibitory activity (62.86%). In a HUA mouse model induced by inosine, guanosine, and potassium oxonate, L. reuteri Urob-7 intervention significantly reduced serum uric acid levels by 46.54%, restoring them to levels similar to control groups, and improved kidney function indicators. Moreover, Urob-7 reduced hepatic XOD activity by 37.6% and downregulated XOD expression in the intestines, decreasing excessive uric acid synthesis. It also significantly inhibited the NF-κB/NLRP3 inflammatory pathway, reducing the expression levels of NF-κB and NLRP3 in the kidneys by 39.3% and 47.6%, respectively. Furthermore, L. reuteri Urob-7 increased the abundance of short-chain fatty acid-producing bacteria (e.g., Ruminococcus and Intestinimonas) while reducing the proportion of pathogenic bacteria (e.g., Bacteroides and Anaerovorax), thus ameliorating gut microbiota dysbiosis and intestinal barrier dysfunction. In summary, L. reuteri Urob-7 effectively relieved HUA by modulating uric acid metabolism, suppressing inflammation, and improving gut microbiota balance. These results highlighted its potential as a promising candidate for HUA. Full article

The gut microbiota plays a crucial role in maintaining swine health and understanding its stage-specific variations provides a scientific basis for health assessment. This study investigated the structural changes in intestinal microbiota during the development of Sichuan–Tibetan black pigs (n = 15) by collecting fecal samples at three growth stages: the nursery period (1 month), growing period (3 months), and finishing period (10 months). Microbial profiling was performed using 16S rRNA sequencing. Results showed no significant difference in the Shannon index between the nursery and growing periods, while the finishing period exhibited distinct ACE and Chao 1 indices compared to other stages. PCoA and NMDS analyses revealed significant structural divergence in the finishing period microbiota, with greater intra-group variability observed in the nursery and growing periods. At the phylum level, Firmicutes abundance increased progressively with growth, becoming the absolute dominant phylum, whereas Bacteroidota showed a declining trend. These characteristics are particularly prominent during the finishing period. At the family level, Lactobacillaceae abundance increased continuously. Oscillospiraceae remained stable during the early stages but decreased significantly in the finishing period. Genus-level analysis shows that Lactobacillus, especially L. amylovorus and L. reuteri, become dominant bacterial species during the finishing period. A total of 84 differentially abundant core microbiota were identified, with the finishing period containing the highest number. Functional annotation revealed 19 significantly different metabolic pathways across the three stages. The most significant is the enhanced activity of microorganisms during the finishing period in pathogen-related metabolism and exogenous degradation, reflecting their adaptability to complex feed. These findings demonstrate stage-dependent variations in the gut microbiota of Sichuan–Tibetan black pigs, providing valuable references for nutritional regulation and feeding management practices. Full article