Dietary tryptophan metabolite released by intratumoral Lactobacillus reuteri facilitates immune checkpoint inhibitor treatment.

The use of probiotics by cancer patients is increasing, including among those undergoing immune checkpoint inhibitor (ICI) treatment. Here, we elucidate a critical microbial-host crosstalk between probiotic-released aryl hydrocarbon receptor (AhR) agonist indole-3-aldehyde (I3A) and CD8 T cells within the tumor microenvironment that potently enhances antitumor immunity and facilitates ICI in preclinical melanoma. Our study reveals that probiotic Lactobacillus reuteri (Lr) translocates to, colonizes, and persists within melanoma, where via its released dietary tryptophan catabolite I3A, it locally promotes interferon-γ-producing CD8 T cells, thereby bolstering ICI. Moreover, Lr-secreted I3A was both necessary and sufficient to drive antitumor immunity, and loss of AhR signaling within CD8 T cells abrogated Lr's antitumor effects. Further, a tryptophan-enriched diet potentiated both Lr- and ICI-induced antitumor immunity, dependent on CD8 T cell AhR signaling. Finally, we provide evidence for a potential role of I3A in promoting ICI efficacy and survival in advanced melanoma patients.

Lactobacillus reuteri derived from horse alleviates Escherichia coli-induced diarrhea by modulating gut microbiota.

Diarrhea is a prevalent health issue in farm animals and poses a significant challenge to the progress of animal husbandry. Recent evidence suggested that probiotics can alleviate diarrhea by maintaining gut microbial balance and enhancing the integrity of the intestinal barrier. However, there is a scarcity of studies investigating the efficacy of equine Lactobacillus reuteri in relieving E. coli-induced diarrhea. Hence, this study aimed to examine the potential of equine-derived Lactobacillus reuteri in alleviating E. coli diarrhea from the perspective of gut microbiota. Results demonstrated that supplementation of Lactobacillus reuteri had the potential to alleviate diarrhea induced by E. coli infection and restore the decline of tight junction genes, such as Claudin-1 and ZO-1. Additionally, Lactobacillus reuteri supplementation can restore the expression of inflammatory factors (IL-6, IL-10, TNF-α, and IFN-γ) and reduce colon inflammatory damage. Diversity analysis, based on amplicon sequencing, revealed a significant reduction in the diversity of gut microbiota during E. coli-induced diarrhea. Moreover, there were notable statistical differences in the composition and structure of gut microbiota among the different treatment groups. E. coli could induce gut microbial dysbiosis by decreasing the abundance of beneficial bacteria, including Lactobacillus, Bifidobacterium, Ligilactobacillus, Enterorhabdus, and Lachnospiraceae_UCG_001, in comparison to the control group. Conversely, supplementation with Lactobacillus reuteri could restore the abundance of beneficial bacteria and increase the diversity of the gut microbiota, thereby reshaping gut microbiota. Additionally, we also observed that supplementation with Lactobacillus reuteri alone improved the gut microbial composition and structure. In summary, the findings suggest that Lactobacillus reuteri can alleviate E. coli-induced diarrhea by preserving the integrity of the intestinal barrier and modulating the composition of the gut microbiota. These results not only contribute to understanding of the mechanism underlying the beneficial effects of Lactobacillus reuteri in relieving diarrhea, but also provide valuable insights for the development of probiotic products aimed at alleviating diarrheal diseases.

IL-6 expression-suppressing Lactobacillus reuteri strains alleviate gut microbiota-induced anxiety and depression in mice.

Fecal microbiota transplantation from patients with depression/inflammatory bowel disease (PDI) causes depression with gut inflammation in mice. Here, we investigated the effects of six Lactobacillus reuteri strains on brain-derived neurotropic factor (BDNF), serotonin, and interleukin (IL)-6 expression in neuronal or macrophage cells and PDI fecal microbiota-cultured microbiota (PcM)-induced depression in mice. Of these strains, L6 most potently increased BDNF and serotonin levels in corticosterone-stimulated SH-SY5Y and PC12 cells, followed by L3. L6 most potently decreased IL-6 expression in lipopolysaccharide (LPS)-stimulated macrophages. When L1 (weakest in vitro), L3, and L6 were orally administered in mice with PcM-induced depression, L6 most potently suppressed depression-like behaviors and hippocampal TNF-α and IL-6 expression and increased hippocampal serotonin, BDNF, 5HT7, GABAARα1, and GABABR1b expression, followed by L3 and L1. L6 also suppressed TNF-α and IL-6 expression in the colon. BDNF or serotonin levels in corticosterone-stimulated neuronal cells were negatively correlated with depression-related biomarkers in PcM-transplanted mice, while IL-6 levels in LPS-stimulated macrophage were positively correlated. These findings suggest that IL-6 expression-suppressing and BDNF/serotonin expression-inducing LBPs in vitro, particularly L6, may alleviate gut microbiota-involved depression with colitis in vivo.

Regulation of neonatal IgA production by the maternal microbiota.

Infants are prone to enteric infections due to an underdeveloped immune system. The maternal microbiota, through shaping the neonatal microbiota, helps establish a strong immune system in infants. We and others have observed the phenomenon of enhanced early neonatal immunoglobulin A (IgA) production in preweaning immunocompetent mice nursed by immunodeficient dams. Here, we show that this enhancement of IgA in neonates results from maternally derived microbiota. In addition, we have found that the neonatal IgA production can be induced by Lactobacillus reuteri, which is enriched in the milk of immunodeficient dams. Moreover, we show that while the production of neonatal IgA is dependent on neonatal T cells, the immunodeficient maternal microbiota-mediated enhancement of neonatal IgA has a T cell-independent component. Indeed, this enhancement may be dependent on type 3 innate lymphoid cells in the neonatal small intestinal lamina propria. Interestingly, maternal microbiota-induced neonatal IgA does not cross-react with common enteric pathogens. Future investigations will determine the functional consequences of having this extra IgA.

The effect of Lactobacillus reuteri on pulmonary function test and growth of cystic fibrosis patients.

INTRODUCTION: Cystic fibrosis (CF) patients frequently experience gut microbiota dysbiosis. Probiotic supplementation is a potential therapeutic approach to modify gut microbiota and improve CF management through the gut-lung axis. The aim of this study was to investigate the effect of Lactobacillus reuteri supplementation on pulmonary function test, respiratory symptoms and growth in CF patients. METHODS: A randomized, placebo-controlled clinical trial was carried out on 40 children with CF aged from 6 to 20 years. Participants were designated to receive either L. reuteri or placebo daily for 4 months. Pulmonary function tests, weight, height and body mass index (BMI) z-scores were measured pre and post treatment. RESULTS: The median baseline BMI of the patients was 16.28 kg m-2. A significant change in the probiotic group's BMI z-score after the study period was observed (P = 0.034) but not for weight and height z-scores (P > 0.05). After treatment, Pseudomonas aeruginosa grew in sputum cultures of seven in the placebo and one patient in the intervention group (P = 0.03) while at baseline it grew in the sputum of four patients in each group. There was no significant difference in forced expiratory volume in the first second, forced expiratory flow at 25-75% or forced vital capacity change between the two groups after the treatment period (P > 0.05). Additionally, no significant differences were found in pulmonary exacerbations, hospitalization frequencies or COVID-19 infection between the two groups during the study (P > 0.05). CONCLUSION: The results suggest that L. reuteri supplementation may impact the growth of severely malnourished CF patients. Furthermore, it may be concluded that this strain might reduce P. aeruginosa in the sputum culture of CF patients. © 2024 Society of Chemical Industry.

Lactobacillus casei combined with Lactobacillus reuteri alleviate pancreatic cancer by inhibiting TLR4 to promote macrophage M1 polarization and regulate gut microbial homeostasis.

BACKGROUND: Pancreatic cancer is a highly lethal disease with no effective treatments. Lactobacillus casei (L. casei) and Lactobacillus reuteri (L. reuteri) exhibited therapeutic effects on several cancers, but their roles in pancreatic cancer are unknown. This study aims to explore how L. casei & L. reuteri influence pancreatic cancer and the underlying mechanisms. METHODS: Pancreatic cancer cells were treated with L. casei & L. reuteri and co-cultured with macrophages in a transwell system in vitro. Pancreatic cancer xenograft model was established and L. casei & L. reuteri was used to treat mice in vivo. MTT, CCK-8 assay or immunohistochemical staining were used to determine the proliferation of pancreatic cancer cells or tumor tissues. Transwell assay was applied to test the migration and invasion of pancreatic cells. RT-qPCR was utilized to assess TLR4 and MyD88 expressions in pancreatic cells or tumor tissues. WB, immunofluorescence staining, or flow cytometry was used to evaluate the M1/M2 polarization of macrophages. Besides, the composition of gut microbiota of tumor-bearing mice was determined by 16 S rRNA sequencing, and ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) untargeted metabolomics was used to evaluate the metabolic profiles of feces. RESULTS: L. casei & L. reuteri inhibited the proliferation, migration, invasion of pancreatic cancer cells and pancreatic cancer cell-induced M2 polarization of macrophages by suppressing TLR4. Meanwhile, L. casei & L. reuteri repressed pancreatic cancer growth and promoted M1 macrophage polarization. Besides, L. casei & L. reuteri reduced fecal Alloprevotella and increased fecal azelate and glutamate in nude mice, while TLR4 inhibitor TAK-242 increased Clostridia UCG-014, azelate, uridine, methionine sulfoxide, oxypurinol, and decreased glyceryl monoester in the feces of pancreatic tumor-bearing mice. Fecal oxypurinol and glyceryl monoester levels were positively or negatively associated with gut Clostridia UCG-014 abundance, respectively. CONCLUSION: L. casei & L. reuteri alleviate pancreatic cancer by inhibiting TLR4 to promote macrophage M1 polarization and regulate gut microbial homeostasis.

Antimicrobial and immunoregulatory effects of Lactobacillus delbrueckii 45E against genitourinary pathogens.

BACKGROUND: Lactobacilli are essential microbiota that maintain a healthy, balanced vaginal environment. Vaginitis is a common infection in women during their reproductive years. Many factors are associated with vaginitis; one of them is the imbalance of microbiota in the vaginal environment. This study aimed to evaluate the antimicrobial properties of Lactobacillus delbrueckii 45E (Ld45E) against several species of bacteria, namely, Group B Streptococcus (GBS), Escherichia coli, Klebsiella spp., and Candida parapsilosis, as well as to determine the concentration of interleukin-17 (IL-17) in the presence of Ld45E. METHODS: The probiotic characteristics of Ld45E were evaluated by examining its morphology, pH tolerance, adhesive ability onto HeLa cells, hemolytic activity, antibiotic susceptibility, and autoaggregation ability. Then, the antimicrobial activity of Ld45E was determined using Ld45E culture, cell-free supernatant, and crude bacteriocin solution. Co-aggregation and competition ability assays against various pathogens were conducted. The immunoregulatory effects of Ld45E were analyzed by measuring the proinflammatory cytokine IL-17. A p-value less than 0.05 was considered statistical significance. RESULTS: Ld45E is 3-5 mm in diameter and round with a flat-shaped colony. pH 4 and 4.5 were the most favorable range for Ld45E growth within 12 h of incubation. Ld45E showed a strong adhesion ability onto HeLa cells (86%) and negative hemolytic activities. Ld45E was also sensitive to ceftriaxone, cefuroxime, ciprofloxacin, and doxycycline. We found that it had a good autoaggregation ability of 80%. Regarding antagonistic properties, Ld45E culture showed strong antimicrobial activity against GBS, E. coli, and Klebsiella spp. but only a moderate effect on C. parapsilosis. Cell-free supernatant of Ld45E exerted the most potent inhibitory effects at 40 °C against all genital pathogens, whereas bacteriocin showed a robust inhibition at 37 °C and 40 °C. The highest co-aggregation affinity was observed with GBS (81%) and E. coli (40%). Competition ability against the adhesion of GBS (80%), E. coli (76%), Klebsiella (72%), and C. parapsilosis (58%) was found. Ld45E was able to reduce the induction of the proinflammatory protein IL-17. CONCLUSIONS: Ld45E possessed antimicrobial and immunoregulatory properties, with better cell-on-cell activity than supernatant activity. Thus, Ld45E is a potential probiotic candidate for adjunct therapy to address vaginal infections.

Probiotic containing Lactobacillus reuteri DSM 17648 as an adjunct treatment for Helicobacter pylori infection: A randomized, double-blind, placebo-controlled trial.

BACKGROUND: Despite multiple therapy regimens, the decline in the Helicobacter pylori eradication rate poses a significant challenge to the medical community. Adding Lactobacillus reuteri probiotic as an adjunct treatment has shown some promising results. This study aims to investigate the efficacy of Lactobacillus reuteri DSM 17648 in H. pylori eradication and its effect in ameliorating gastrointestinal symptoms and adverse treatment effects. MATERIALS AND METHODS: This randomized, double-blinded, placebo-controlled trial involved treatment-naïve H. pylori-positive patients. Ninety patients received standard triple therapy for 2 weeks before receiving either a probiotic or placebo for 4 weeks. The posttreatment eradication rate was assessed via a 14 C urea breath test in Week 8. The Gastrointestinal Symptom Rating Scale (GSRS) questionnaire and an interview on treatment adverse effects were conducted during this study. RESULTS: The eradication rate was higher in the probiotic group than in the placebo group, with a 22.2% difference in the intention-to-treat analysis (91.1% vs. 68.9%; p = 0.007) and 24.3% difference in the per-protocol analysis (93.2% vs. 68.9%; p = 0.007). The probiotic group showed significant pre- to post-treatment reductions in indigestion, constipation, abdominal pain, and total GSRS scores. The probiotic group showed significantly greater reductions in GSRS scores than the placebo group: indigestion (4.34 ± 5.00 vs. 1.78 ± 5.64; p = 0.026), abdominal pain (2.64 ± 2.88 vs. 0.89 ± 3.11; p = 0.007), constipation (2.34 ± 3.91 vs. 0.64 ± 2.92; p = 0.023), and total score (12.41 ± 12.19 vs. 4.24 ± 13.72; p = 0.004). The probiotic group reported significantly fewer adverse headache (0% vs. 15.6%; p = 0.012) and abdominal pain (0% vs. 13.3%; p = 0.026) effects. CONCLUSIONS: There was a significant increase in H. pylori eradication rate and attenuation of symptoms and adverse treatment effects when L. reuteri was given as an adjunct treatment.

A systematic review and meta-analysis: the therapeutic and preventive effect of Lactobacillus reuteri DSM 17,938 addition in children with diarrhea.

OBJECTIVE: To summarize the effect of adding Lactobacillus reuteri in the treatment plan for diarrheal disease in children, and analyze the potential of probiotics in preventing the occurrence of diarrheal disease. METHODS: Search for randomized controlled trials of Lactobacillus reuteri for the treatment and prevention of diarrhea in the Pubmed, Web of science, Medline, and Cochrane databases. Data such as the number of diarrhea patients, time, length of stay, clinical symptoms and effect of diarrhea prevention were extracted for meta-analysis. Relative risk and confidence interval (RR and 95% CI) were used as outcome indicators. RESULTS: 963 participants in the 9 RCTs came from multiple countries/regions. Compared with placebo/no intervention, the number of diarrhea patients in the Lactobacillus reuteri group was significantly reduced on the day 1 (RR = 0.87, 95%CI: 0.78-0.97) and day 2 (RR = 0.61, 95%CI: 0.44-0.83). Cumulative statistics analysis showed that the effect was stable and significant starting on the 4th day after treatment. A few studies have shown that Lactobacillus reuteri can reduce the time of diarrhea, the number of days with watery stools, and days of hospital stay. However, it has no effect on the occurrence of nosocomial diarrhea (RR = 1.11, 95%CI: 0.68-1.83), rotavirus diarrhea (RR = 1.46, 95%CI: 0.78-2.72), antibiotic-related diarrhea (RR = 1.76, 95%CI: 0.77-4.05), and diarrhea (RR = 1.35, 95%CI: 0.95-1.92). CONCLUSION: Addition of Lactobacillus reuteri in the treatment plan has a significant effect on reducing the number of diarrhea and reducing the symptoms of diarrhea, but has no obvious effect on the prevention of diarrhea. Combining probiotics and improving the ability of probiotics to respond is the focus of attention.

Fecal miR-142a-3p from dextran sulfate sodium-challenge recovered mice prevents colitis by promoting the growth of Lactobacillus reuteri.

Feces are enriched with microRNAs (miRNAs) that shape the gut microbiota. These miRNAs are differentially expressed in the feces of healthy and diseased subjects. However, whether fecal miRNAs in subjects with inflammatory bowel diseases are involved in regulating microbiota composition and whether they have any beneficial effects remains unknown. Here, we studied the fecal microbiome composition and miRNA abundance in mice with dextran sulfate sodium (DSS)-induced colitis and mice at the recovery phase to explore different miRNAs expressed, their relations with microbial abundance, and their effects on colitis. We found that miR-142a-3p expression was significantly increased in the feces of mice recovered from colitis and that it could alleviate disease symptoms in mice treated with DSS in a microbiome-dependent manner. Specifically, miR-142a-3p promoted the growth of Lactobacillus reuteri, which had a high abundance in the feces of mice recovered from colitis, by regulating transcripts of polA and locus tag LREU_RS03575. Moreover, L. reuteri, as well as its metabolite reuterin, could alleviate DSS-induced disease symptoms. These results highlight the role of fecal miR-142a-3p in the prevention of colitis. We propose that the feces of subjects who have recovered from diseases might be enriched with miRNAs with preventive effects against those diseases.

Edible exosome-like nanoparticles from portulaca oleracea L mitigate DSS-induced colitis via facilitating double-positive CD4+CD8+T cells expansion.

Plant-derived exosome-like nanoparticles (PDENs) have been paid great attention in the treatment of ulcerative colitis (UC). As a proof of concept, we isolated and identified Portulaca oleracea L-derived exosome-like nanoparticles (PELNs) from edible Portulaca oleracea L, which exhibited desirable nano-size (~ 160 nm) and a negative zeta potential value (-31.4 mV). Oral administration of PELNs effectively suppressed the expressions of pro-inflammatory cytokines (TNF-α, IL-6, IL-12, and IL-1ß) and myeloperoxidase (MPO), increased levels of the anti-inflammatory cytokine (IL-10), and alleviated acute colitis in dextran sulfate sodium (DSS)-induced C57 mice and IL-10-/- mice. Notably, PELNs exhibited excellent stability and safety within the gastrointestinal tract and displayed specific targeting to inflamed sites in the colons of mice. Mechanistically, oral administration of PELNs played a crucial role in maintaining the diversity and balance of gut microbiota. Furthermore, PELNs treatment enhanced Lactobacillus reuteri growth and elevated indole derivative levels, which might activate the aryl-hydrocarbon receptor (AhR) in conventional CD4+ T cells. This activation downregulated Zbtb7b expression, leading to the reprogramming of conventional CD4+ T cells into double-positive CD4+CD8+T cells (DP CD4+CD8+ T cells). In conclusion, our findings highlighted the potential of orally administered PELNs as a novel, natural, and colon-targeted agent, offering a promising therapeutic approach for managing UC. Schematic illustration of therapeutic effects of oral Portulaca oleracea L -derived natural exosome-like nanoparticles (PELNs) on UC. PELNs treatment enhanced Lactobacillus reuteri growth and elevated indole derivative levels, which activate the aryl-hydrocarbon receptor (AhR) in conventional CD4+ T cells leading to downregulate the expression of Zbtb7b, reprogram of conventional CD4+ T cells into double-positive CD4+CD8+T cells (DP CD4+CD8+ T cells), and decrease the levels of pro-inflammatory cytokines.

Mechanistic study of copper oxide, zinc oxide, cadmium oxide, and silver nanoparticles-mediated toxicity on the probiotic Lactobacillus reuteri.

The use of metal/metal oxide nanoparticles (NPs) in consumer products has increased dramatically. Accordingly, human exposure to these NPs has increased. Lactobacillus reuteri, a member of the beneficial gut microbiota, is essential for human health. In the present study, the toxic effect of three metal oxides (CuO, ZnO, and CdO) and one metal (Ag) NPs on L. reuteri were investigated in vitro. L. reuteri was susceptible to all the prepared NPs in a dose-dependent manner, visualized as an increase in the zones of inhibition and a significant reduction in the maximum specific growth rates (µmax). The minimal inhibitory concentrations were 5.8, 26, 560, and 560 µg/mL for CdO-, Ag-, ZnO-, and CuO-NPs, respectively, and the respective minimal bactericidal concentrations were 60, 70, 1500, and 1500 µg/mL. Electron microscopic examinations revealed the adsorption of the prepared NPs on L. reuteri cell surface, causing cell wall disruption and morphological changes. These changes were accompanied by significant leakage of cellular protein content by 214%, 191%, 112%, and 101% versus the untreated control when L. reuteri was treated with CdO-, Ag-, CuO-, and ZnO-NPs, respectively. NPs also induced oxidative damage, where the malondialdehyde level was significantly increased, and glutathione content was significantly decreased. Quantifying the DNA damage using comet assay showed that CuONPs had the maximum DNA tail length (8.2 px vs. 2.1 px for the control). While CdONPs showed the maximum percentage of DNA in tail (15.5% vs. 3.1%). This study provides a mechanistic evaluation of the NPs-mediated toxicity to a beneficial microorganism.

Mutanolysin-Digested Peptidoglycan of Lactobacillus reuteri Promotes the Inhibition of Porphyromonas gingivalis Lipopolysaccharide-Induced Inflammatory Responses through the Regulation of Signaling Cascades via TLR4 Suppression.

Periodontitis is an oral infectious disease caused by various pathogenic bacteria, such as Porphyromonas gingivalis. Although probiotics and their cellular components have demonstrated positive effects on periodontitis, the beneficial impact of peptidoglycan (PGN) from probiotic Lactobacillus remains unclear. Therefore, our study sought to investigate the inhibitory effect of PGN isolated from L. reuteri (LrPGN) on P. gingivalis-induced inflammatory responses. Pretreatment with LrPGN significantly inhibited the production of interleukin (IL)-1ß, IL-6, and CCL20 in RAW 264.7 cells induced by P. gingivalis lipopolysaccharide (LPS). LrPGN reduced the phosphorylation of PI3K/Akt and MAPKs, as well as NF-κB activation, which were induced by P. gingivalis LPS. Furthermore, LrPGN dose-dependently reduced the expression of Toll-like receptor 4 (TLR4), indicating that LrPGN inhibits periodontal inflammation by regulating cellular signaling cascades through TLR4 suppression. Notably, LrPGN exhibited stronger inhibition of P. gingivalis LPS-induced production of inflammatory mediators compared to insoluble LrPGN and proteinase K-treated LrPGN. Moreover, MDP, a minimal bioactive PGN motif, also dose-dependently inhibited P. gingivalis LPS-induced inflammatory mediators, suggesting that MDP-like molecules present in the LrPGN structure may play a crucial role in the inhibition of inflammatory responses. Collectively, these findings suggest that LrPGN can mitigate periodontal inflammation and could be a useful agent for the prevention and treatment of periodontitis.

Characterization of a novel theta-type replicon of indigenous plasmid pTE15 from Lactobacillus reuteri N16.

BACKGROUND: pTE15 is a ~ 15-kb narrow-host-range indigenous plasmid from Lactobacillus reuteri N16 that does not replicate in selected Bacillus spp., Staphylococcus spp., and other Lactobacillus spp. METHODS: Combined deletion analysis the minireplicon essential of pTE15 with replicon-probe vector pUE80 (-) to confirmed sufficient for replication and from the ssDNA intermediate detection, plasmid amplification tested by chloramphenicol treatment, and replication origin sequence analysis to delineated the novel theta-type replication of pTE15. RESULTS: Single-stranded intermediate of pTE15 DNA was not detected in L. reuteri, indicating that this plasmid does not replicate via a rolling circle mechanism. The replicon of pTE15 did not display the structural organization typical of rolling-circle plasmids, nor were they similar to known rolling-circle plasmids. We further provided evidence that this plasmid applied a new mode of theta-type replication mechanism: (1) the size of this plasmid was > 10-kb; (2) the minireplicon consisted of AT-rich (directed repeat, iteron) and DnaA sequences; (3) the minireplicon did not contain double-strand origin (DSO) and essential rep genes, and it also showed no single-strand origin (SSO) structure; (4) the intermediate single-stranded DNA products were not observed for pTE15 replication; (5) the minireplicon did not contain a typical essential replication protein, Rep, (6) its copy number was decreased by chloramphenicol treatment, and (7) genes in pTE15 replication region encoded truncated RepA (TRepA), RepB and RepC, which were replication-associated proteins, but they were not essential for pTE15 replication. CONCLUSIONS: Collectively, our results strongly suggested that the indigenous plasmid pTE15 of L. reuteri N16 belongs to a new class of theta replicons.

Investigating the effect of quadruple therapy with Saccharomyces boulardii or Lactobacillus reuteri strain (DSMZ 17648) supplements on eradication of Helicobacter pylori and treatments adverse effects: a double-blind placebo-controlled randomized clinical trial.

BACKGROUND: The goal of this study was to investigate the effects of treatment with Saccharomyces boulardii and Lactobacillus reuteri on the eradication of Helicobacter pylori and Adverse effects (AEs) of the treatment. RESULTS: This study was a double-blind, randomized, placebo-controlled trial. And, eradication of H. pylori was reported comparing quadruple therapy include of PPI (proton pomp inhibitor), bismuth subcitrate, clarithromycin, and amoxicillin versus quadruple therapy supplemented with S. boulardii and L. reuteri DSMZ 17648. For this aim, a total of 156 patients were included in the current study; and patients positive for H. pylori infection (n = 156) were randomly assigned to 3 groups: 52 patients (Group P) received conventional quadruple therapy plus L. reuteri, 52 patients (Group S) received conventional quadruple therapy plus S. boulardii daily, for 2 weeks, and 52 patients were in the control group (Group C). At the end of the treatment period, all the subjects continued to take proton pump inhibitor (PPI) alone for 14 days, and then, no medication was given for 2 weeks again. During follow-up, gastrointestinal symptoms were assessed using an evaluation scale (Glasgow dyspepsia questionnaire [GDQ]), and AEs were assessed at 7, 14, 21, and 28 days. As a result, all patients completed the treatment protocol in all groups by the end of the study. Additionally, eradication therapy was effective for 94.2% of subjects in Group S, 92.3% of subjects in Group P, and 86.5% of subjects in the control group, with no differences between treatment arms. In Group S, the chance of developing symptoms of nausea (OR = 2.74), diarrhea (OR = 3.01), headache (OR = 10.51), abdominal pain (OR = 3.21), and anxiety (OR = 3.58) was significantly lower than in the control group (p < 0.05). CONCLUSION: S. boulardii could significantly reduce some AEs of H. pylori eradication therapy, but effectiveness of Lactobacillus reuteri on these cases was not significant. It is recommended to conduct the future research with larger sample size in order to investigate the effect. TRIAL REGISTRATION: IRCT20200106046021N1, this trial was registered on Jan 14, 2020.

Anti-inflammatory potential of Lactobacillus reuteri LM1071 via eicosanoid regulation in LPS-stimulated RAW264.7 cells.

AIMS: To investigate anti-inflammatory effects of Lactobacillus reuteri LM1071 in lipopolysaccharides (LPS)-induced inflammation RAW264.7 cells. METHODS AND RESULTS: To evaluate anti-inflammatory activities of L. reuteri LM1071, LPS-stimulated RAW264.7 cells were used. Gene expression levels of eight immune-associated genes including IL-1ß, IL-6 and TNF-α and protein production levels of COX-1 and COX-2 were analysed. Moreover, the production of eicosanoids as important biomarkers for anti-inflammation was determined. CONCLUSIONS: The current study demonstrates that L. reuteri LM1071 has anti-inflammatory potential by inhibiting the production of inflammation mediators such as NO, eicosanoids such as PGE1 & PGE2, pro-inflammatory cytokines and COX proteins. It can also enhance the production of inflammatory associated genes such as IL-11, BMP4, LEFTY2 and EET metabolite. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus reuteri is one of the crucial bacteria for food fermentation. It can be found in the gastrointestinal system of human and animals. Several studies have shown that L. reuteri has valuable effects on host health. The current study firstly demonstrated that L. reuteri has a beneficial effect on the inflammation containing the variation of eicosanoids (PGE1 and PGE2) which are one of the most important biomarkers and moreover eicosanoid-associated genes as well as proteins (COX-2).

Effects of sucrose, carnosine, and their mixture on the glass transition behavior and storage stability of freeze-dried lactic acid bacteria at various water activities.

Effects of sucrose, carnosine, and their mixture on the glass transition behavior and storage stability of freeze-dried Lactobacillus reuteri at various water activities (aw) were investigated. At aw = 0.328, the control (non-additive sample) showed viable cells as uncountable after storage at 25 °C for 4 weeks. The sucrose and sucrose-carnosine samples showed clear glass transition at a slightly lower temperature than the storage temperature, and maintained a large number of viable cells after storage. The carnosine sample crystalized during the storage, and a large reduction in viable cells was observed. At aw = 0.576, the samples showed a small endothermic shift due to glass transition, suggesting partial crystallization. The Tg decreased with increase in aw because of the water plasticizing effect. After storage, the sucrose-carnosine sample showed much higher viable cell numbers than the other samples. At aw = 0.753, the sucrose and sucrose-carnosine samples showed clear glass transition. The carnosine sample showed freeze-concentrated glass transition and subsequent ice melting. After storage, the sucrose and carnosine samples showed an uncountable and a low number of viable cells, respectively, but sucrose-carnosine maintained relatively high viable cell numbers. In addition, carnosine strongly supported the stabilizing effect of sucrose (even at low additive levels) depending on the aw. These results suggest that sucrose-carnosine shows a synergistic stabilizing effect.

Intestinal Radiation Protection and Mitigation by Second-Generation Probiotic Lactobacillus-reuteri Engineered to Deliver Interleukin-22.

(1) Background: The systemic administration of therapeutic agents to the intestine including cytokines, such as Interleukin-22 (IL-22), is compromised by damage to the microvasculature 24 hrs after total body irradiation (TBI). At that time, there is significant death of intestinal microvascular endothelial cells and destruction of the lamina propria, which limits drug delivery through the circulation, thus reducing the capacity of therapeutics to stabilize the numbers of Lgr5+ intestinal crypt stem cells and their progeny, and improve survival. By its direct action on intestinal stem cells and their villus regeneration capacity, IL-22 is both an ionizing irradiation protector and mitigator. (2) Methods: To improve delivery of IL-22 to the irradiated intestine, we gavaged Lactobacillus-reuteri as a platform for the second-generation probiotic Lactobacillus-reuteri-Interleukin-22 (LR-IL-22). (3) Results: There was effective radiation mitigation by gavage of LR-IL-22 at 24 h after intestinal irradiation. Multiple biomarkers of radiation damage to the intestine, immune system and bone marrow were improved by LR-IL-22 compared to the gavage of control LR or intraperitoneal injection of IL-22 protein. (4) Conclusions: Oral administration of LR-IL-22 is an effective protector and mitigator of intestinal irradiation damage.

Influence of probiotics on the periodontium, the oral microbiota and the immune response during orthodontic treatment in adolescent and adult patients (ProMB Trial): study protocol for a prospective, double-blind, controlled, randomized clinical trial.

BACKGROUND: Orthodontic treatment with fixed appliances is often necessary to correct malocclusions in adolescence or adulthood. However, oral hygiene is complicated by appliances, and prior studies indicate that they may trigger oral inflammation and dysbiosis of the oral microbiota, especially during the first 3 months after insertion, and, thus, may present a risk for inflammatory oral diseases. In recent periodontal therapeutic studies, probiotics have been applied to improve clinical parameters and reduce local inflammation. However, limited knowledge exists concerning the effects of probiotics in orthodontics. Therefore, the aim of our study is to evaluate the impact of probiotics during orthodontic treatment. METHODS: This study is a monocentric, randomized, double blind, controlled clinical study to investigate the effectiveness of daily adjuvant use of Limosilactobacillus reuteri (Prodentis®-lozenges, DSM 17938, ATCC PTA 5289) versus control lozenges during the first three months of orthodontic treatment with fixed appliances. Following power analysis, a total of 34 adolescent patients (age 12-17) and 34 adult patients (18 years and older) undergoing orthodontic treatment at the University Hospital Erlangen will be assigned into 2 parallel groups using a randomization plan for each age group. The primary outcome measure is the change of the gingival index after 4 weeks. Secondary outcomes include the probing pocket depth, the modified plaque index, the composition of the oral microbiota, the local cytokine expression and-only for adults-serum cytokine levels and the frequencies of cells of the innate and adaptive immune system in peripheral blood. DISCUSSION: Preventive strategies in everyday orthodontic practice include oral hygiene instructions and regular dental cleaning. Innovative methods, like adjuvant use of oral probiotics, are missing. The aim of this study is to analyse, whether probiotics can improve clinical parameters, reduce inflammation and prevent dysbiosis of the oral microbiota during orthodontic treatment. If successful, this study will provide the basis for a new strategy of prophylaxis of oral dysbiosis-related diseases during treatment with fixed appliances. TRIAL REGISTRATION: This trial is registered at ClinicalTrials.gov in two parts under the number NCT04598633 (Adolescents, registration date 10/22/2020), and NCT04606186 (Adults, registration date 10/28/2020).

Adhesion Characteristics and Dual Transcriptomic and Proteomic Analysis of Lactobacillus reuteri SH23 upon Gastrointestinal Fluid Stress.

The ability to survive in the harsh gastrointestinal tract (GIT) environment is essential for Lactobacillus reuteri (L. reuteri) exhibiting beneficial effects. In this study, we found that the hydrophobicity and auto-aggregation of L. reuteri SH23 were significantly decreased and biofilm production was also significantly decreased when L. reuteri SH23 passes through the simulated GIT. Furthermore, according to the comparative transcriptome analysis, gene expression involved in the cell envelope, metabolic processes, common stress response, regulatory systems, and transporters were also affected. Meanwhile, label-free quantitative proteomics was used to identify the differential expression of surface proteins of L. reuteri in response to simulated gastrointestinal fluid. Proteins related to the ABC transporters (Lreu_0517, Lreu_0098, and Lreu_0296) and LPxTG anchor domain proteins were upregulated in the cell surface after gastrointestinal fluid treatment, which is useful for adherence and colonization of L. reuteri in the GIT. Additionally, the recombinant Mub protein could also enhance the survival ability of L. reuteri SH23 in GIT stress environment. This study provides a comprehensive understanding of the adaptation and adhesion mechanisms of L. reuteri SH23 under the gastrointestinal tract by the transcriptomics and proteomics analysis, and mucus-binding proteins were involved in the adhesion and GIT tolerance process.