Lactobacillus gasseri CP2305 (L. gasseri CP2305) has been reported to exert intestinal regulatory, anti-stress, and sleep-improving effects in healthy adults. This study aimed to evaluate the safety of an excessive intake of L. gasseri CP2305 in a randomized, double-blind, placebo-controlled, parallel-group trial. Among 95 participants who provided written informed consent, 44 who met the eligibility criteria were randomly assigned to either the L. gasseri CP2305 group (n = 22) or the placebo group (n = 22). All participants ingested 20 tablets of either L. gasseri CP2305 or placebo daily for 4 weeks. The L. gasseri CP2305 group consumed 1.0 × 10 ¹ ¹ cells of L. gasseri CP2305 cells per day. To assess the safety of CP2305 tablets, physical examinations, hematological and biochemical blood tests, urinalysis, recording of subjective symptoms, and physician interviews were conducted. One participant was excluded from the analysis; thus, the final analysis included data from 22 participants in the L. gasseri CP2305 group and 21 participants in the placebo group. No adverse clinical findings were observed in either group. The results of this study demonstrate that no safety concerns were identified in the physical examinations, hematology, blood biochemistry, urinalysis, or subjective symptoms. These findings support the safety of L. gasseri CP2305 tablets even at high-dose intake (1.0 ×10 ¹¹ cells/day).

Understanding the probiotic potential of a healthy human vaginal flora, Lactobacillus gasseri K9: genomic and in vitro aspects

To date, various probiotic lactobacilli have been tested against Helicobacter pylori. However, a detailed molecular analysis of the various signaling pathways and their associated anti-proliferative activity remains poorly understood. In our previously published research, a disintegrin and metalloprotease 17 (ADAM17) was proposed as a key target for anti-inflammatory activity in H. pylori-infected host macrophages. Therefore, in this study, the anti-H. pylori activity of selected lactobacilli was assessed based on expression of ADAM17 and two of its targets, heparin-binding EGF-like growth factor (HBEGF) and transforming growth factor-alpha (TGF-α), which were measured in gastric epithelial cells. For this purpose, lactobacilli and H. pylori were either added together to the AGS cells (coincubation), or the cells were first exposed to lactobacilli before H. pylori infection (preincubation). In coincubation assays, lactobacilli had no effect on H. pylori-mediated ADAM17, HBEGF, and TGF-α upregulation at the protein level. However, in preincubation assays, L. gasseri downregulated the expression of ADAM17 and its substrates. Furthermore, the proliferation data demonstrated that L. gasseri suppressed H. pylori-induced cellular progression. Using an in vivo mouse model, the anti-inflammatory activity of selected lactobacilli was tested by measuring blood cytokine profiles and tissue staining. L. gasseri significantly decreased the levels of the pro-inflammatory cytokine TNF and reduced immune cell infiltration in stained gastric tissues. Together, these findings suggest that certain lactobacilli can counteract the H. pylori-mediated induction of HBEGF and TGF-α expression, and indicate that ADAM17 could be targeted to inhibit the cancer-related effects of H. pylori.

Lysate-based cell-free systems (CFS) mimic cellular functions in a controllable environment, making them versatile synthetic biology tools used from fundamental research to protein production and synthetic circuit prototyping. Here, we establish a streamlined and robust Bacillus subtilis CFS by systematically re-evaluating the traditional extract preparation and reaction environment. We show that the conventionally required runoff incubation and labor-intensive dialysis steps can be omitted without compromising performance. A key advance is the reformulation of the reaction buffer: increasing ionic strength with potassium glutamate concentration to 400 mM and adding the osmoprotectant betaine significantly enhanced translational capacity, yielding 2-3 μM sfGFP. Benchmarking against established in vivo promoter library data sets revealed that the relative hierarchy of promoter strengths is preserved, validating the platform as a predictive proxy for bacterial physiology. We further reconstituted complex genetic regulations by demonstrating functional repression of a cre-box-containing promoter by the catabolite repressor CcpA in complex with HPr, activated through a phosphorylation cascade within the CFS. Finally, we show that this high-glutamate framework is beneficial for another Gram-positive bacterium, Lactobacillus gasseri, suggesting a broad-host compatibility. Together, the simplified preparation and optimized buffer composition provide a versatile toolkit for developing CFS in diverse, nonmodel bacterial species.

To describe both host gene expression and microbiome composition in a single sample, parallel experimental and computational workflows (mRNA-sequencing and either 16S rRNA gene or metagenomics) have been traditionally applied. The vulvar milieu represents an area of emerging research for its role in health and disease. Located at the interface between the vagina and the perineum, the vulvar microbiome displays an intermediate signature, with influx from both ecosystems. Following validation of the reliability of poly(A)-enriched mRNA-sequencing in reconstructing the microbiota composition using both a quantitative microbial standard (mock) and metagenomic analysis, we analyze a full cohort of 30 healthy vulvar samples. Crucially, the analysis of the entire cohort relies solely on mRNA-sequencing without the use of parallel DNA metagenomics. This unified approach allows us to analyze not only the vulvar cell transcriptome, but also the composition and dynamics of microbial communities, including the microbial gene expression signatures. This three-level analysis (host-mRNA, individual bacterial species, bacterial gene pathways) on the very same specimens further enables a gene-level exploration of host-microbe molecular crosstalk. Using this unified framework, we reveal marked heterogeneity and high inter-individual variability in the vulvar microbiota, identifying community state types that mirror those described in the vagina. Importantly, we show that distinct microbial configurations are associated with specific host transcriptional programs: Lactobacillus crispatus correlates with epithelial differentiation and barrier integrity, whereas communities enriched in Gardnerella vaginalis, or other taxa associated with dysbiosis, exhibit transcriptional signatures linked to inflammation. Interestingly, Lactobacillus gasseri, which has been associated with lower protection, shows an intermediate effect on vulvar cells. Beyond providing new biological insights into an understudied anatomical niche, our study introduces a broadly applicable strategy with substantial impact for the field. With tens of thousands of human RNA-seq datasets already available in public repositories, our approach enables retrospective extraction of microbiome information and host-microbe interaction signals from existing transcriptomic data, without the need for additional sequencing or specialized microbiome protocols. This unlocks a powerful and cost-effective opportunity to revisit archived RNA-seq studies across tissues, diseases, and low-biomass environments, revealing previously inaccessible layers of host-microbiome crosstalk and maximizing the scientific value of published data. Video Abstract.

Glycoside hydrolase-mediated utilization of Poria cocos polysaccharide enriches Lactobacillus gasseri and activates the AhR-IL-22 axis to attenuate DSS-induced colitis.

Urinary tract infection (UTI) is one of the most common bacterial infections, contributing to increased antibiotic consumption and high healthcare costs. Clinical studies suggest that probiotics can be effective dietary supplements reducing the risk factors for the development of infections in the intestine and vagina. In this study, we investigate the effect of the orally ingested probiotic combination ASTARTE™ on the composition of bacteria in vaginal and fecal samples, as well as on the occurrence of bacteriologically confirmed UTIs in women of reproductive age. A randomized, placebo-controlled, double-blind study evaluating the effect of the probiotic combination ASTARTE™ (Chr. Hansen A/S, Part of Novonesis Group, Denmark) on reducing the number of recurrent urinary tract infections (rUTIs) in women aged 18-40years. Participants are randomized (1:1) to receive one daily probiotic capsule (5 × 109 CFU) containing Lactobacillus crispatus LBV 88™ (DSM22566), Lacticaseibacillus rhamnosus LBV 96™ (DSM22560), Lactobacillus jensenii LBV 116™ (DSM22567), and Lactobacillus gasseri LBV 150N™ (DSM22583), or placebo, for 6 months. Assessments, including symptom questionnaires, urine culturing and microbiome analysis of vaginal and rectal samples by shotgun sequencing, are conducted at baseline, 2, 4, and 6months. Compliance is tracked by unused capsule counts. Follow-up visits occur at 8, 10, and 12months. The primary outcome is the incidence of symptomatic bacteriologically confirmed UTIs during the 6months intervention period. The secondary objective is the effect of ASTARTE™ on changes in vaginal and gut microbiome. This randomized, placebo-controlled, double-blind study investigates the effectiveness of ASTARTE™ in restoring beneficial microbiomes and reducing UTI recurrence. The findings will provide valuable evidence on the effectiveness of a non-antibiotic strategy for the prevention of rUTI as well as insights into the complex interactions between the vaginal and gut microbiome and the risk of rUTI. ClinicalTrials.gov Identifier: NCT05553652. Registered 21 September 2022.

The increasing prevalence of obesity worldwide has highlighted the need for adjunct strategies targeting metabolic dysfunction beyond simple weight reduction. This review aimed to evaluate the hypothesis that the anti-obesity effects of probiotics are mediated through modifications in fat distribution, metabolic inflammation, and appetite regulation rather than reductions in body weight or body mass index (BMI). A critical appraisal of recent randomized, double-blind, placebo-controlled human clinical trials was conducted, focusing on the effects of probiotic supplementation on adiposity, fat distribution, metabolic parameters, and eating behaviors. The evidence indicates that probiotic strains, particularly Lactobacillus gasseri and Bifidobacterium breve, are consistently associated with reductions in visceral fat, total body fat, waist circumference (WC), and body fat percentage, while effects on body weight and BMI remain modest. Strains of Lacticaseibacillus rhamnosus showed improvements in satiety. Probiotic supplementation with B. breve, B. pseudocatenulatum, L. plantarum Inducia were also linked to improvements in lipid metabolism, glucose homeostasis, inflammatory markers, and appetite regulation. Notably, several studies reported more pronounced effects in female participants. Overall, these findings suggest that probiotics exert anti-obesity effects primarily through metabolic and compositional changes rather than direct weight loss, supporting their role as a complementary strategy in obesity management.

Recent research has highlighted the gut-brain axis as a critical modulator of mental health, positioning probiotics as promising psychobiotic interventions for anxiety, stress, depression, and cognitive function. Clinical trials investigating strains such as Lactobacillus rhamnosus, Bifidobacterium longum, Lactobacillus gasseri, and multi-strain formulations have demonstrated strain- and context-specific effects on psychological and physiological outcomes. While some studies reported improvements in mood, anxiety, sleep quality, and cognitive performance, others showed limited effects, particularly in healthy populations with low baseline stress levels, reflecting the challenges of translating preclinical findings into clinical applications in humans. Mechanistic evidence suggests that psychobiotics may influence neuroactive metabolites, short-chain fatty acids, γ-aminobutyric acid, serotonin, and anti-inflammatory pathways, thereby modulating cognitive and emotional processes. The effects happen dependent on factors such as dosage, strain specificity, delivery method, baseline stress or symptom levels, and co-administration with conventional treatments. Collectively, these findings underscore the potential of targeted psychobiotics to enhance mental well-being and support stress resilience, while highlighting the need for carefully designed clinical trials to clarify efficacy and mechanisms.

Lactobacillus gasseri TF08-1 Alleviates DSS-Induced Acute Colitis by Protecting Intestinal Epithelial Barrier.

Modulation of the gut microbiome-adipose tissue AXIS by maqui supplementation improved insulin resistance and lipid metabolism in mice under a high-fat diet

The healthy vaginal microbiota is typically dominated by Lactobacillus species, while the dominance of different taxa often signals dysbiosis. Vaginal probiotics offer a promising therapeutic avenue to restore microbial balance and prevent recurrent infections. Using probiogenomics, this study investigated 19 novel strains belonging to four Lactobacillus species (Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus paragasseri, Limosilactobacillus fermentum) isolated from the vaginal environment of fertile and menopausal women. Through genomic screening and comparative genomics, we identified complementary roles between these species in activities crucial to women’s health. Our results indicate that vaginal Lactobacillus strains are genomically adapted to this niche, promoting persistence and pathogen-fighting. Furthermore, we demonstrated the potential ability of vaginal lactobacilli to survive the gastrointestinal transit and to explicate beneficial activities at the intestinal level, suggestion the possibility to be used through oral supplementation when topical application is not feasible. Although we confirmed L. crispatus as the most specialized to the vaginal niche, L. gasseri showed equivalent and complementary genetic traits, highlighting its previously underestimated role. L. paragasseri showed an interesting dichotomy, with beneficial traits alongside potentially unfavorable ones, while Lm. fermentum of vaginal origin may potentially have a role in the gut-vagina axis. In conclusion, our results strongly support the development of multispecies and multistrain probiotic blends, as the combined metabolic cooperation of vaginal lactobacilli may offer greater efficacy for vaginal health compared to single-strain supplements.

Background and aimsAntibiotic use in early life is increasingly being scrutinized for its potential effects on health, particularly its association with inflammatory bowel disease (IBD). The weaning period is a critical developmental window for maturation of the intestinal barrier, immune system and gut microbiota. However, it remains unknown how administering antibiotics to male mice starting at weaning affects the susceptibility of their future offspring to IBD.MethodsThree-week-old weaned male mice were used to investigate the effects of short-term (1 week) and long-term (6 weeks) administration with ampicillin and cefixime on colitis susceptibility in adulthood and in the subsequent F1 generation. Paternal and F1 offspring were administered dextran sodium sulfate (DSS) to induce colitis. Quantitative real-time polymerase chain reaction, immunoblotting, immunofluorescence staining, and histological examination were used to assess mRNA and protein expression and morphological changes. Full 16S rRNA and miRNA sequencing was used to assess changes in the gut microbiota compositions and the mechanisms of intergenerational transmission of intestinal phenotypes. A dual-luciferase reporter assay was used to decipher the direct regulation of miR-10b-5p and miR-200b-3p on Occludin 3′ UTR.ResultsBoth short- and long-term antibiotic administration during the weaning period significantly alleviated DSS-induced colitis in male paternal mice, with long-term administration conferring a more pronounced protective effect. Interestingly, the protective effect against DSS-induced colitis was observed in LONG_F1 offspring, which was more pronounced in F1 males than in F1 females. Mechanistically, the protective effect was associated with increased expression of Occludin in epithelial cells, which was negatively modulated by miR-10b-5p and miR-200b-3p. This effect was inherited via the sperm. Furthermore, long-term antibiotic administration significantly altered the gut microbiota of paternal males, increasing the abundance of certain beneficial bacteria, such as Lactobacillus gasseri and Parabacteroides merdae, while promoting the enrichment of antibiotic-resistant strains.ConclusionsLong-term antibiotic administration initiated at the weaning stage in male mice improves colitis in adulthood and in their offspring that associates with decreasing miR-10b-5p and miR-200b-3p expression, thus providing a theoretical basis for optimizing the use of antibiotics and prevention of IBD.

Background: Many probiotic strains have been studied in relation to irritable bowel syndrome (IBS). The aim of this study was to identify probiotic strains demonstrating efficacy in the management of IBS based on meta-analyses of randomized placebo-controlled trials (RPCTs). Methods: This systematic review was registered in the PROSPERO database (CRD420251047092). Searches were conducted in PubMed and Scopus on 8 April 2025. Additional completed studies with available results were identified through ClinicalTrials.gov. An additional search of the Cochrane Central Register of Controlled Trials (CENTRAL), including records indexed in EMBASE, was conducted in December 2025 and did not identify any additional studies. RPCTs were included if they evaluated single-strain probiotics without additional active components compared with a placebo in patients with IBS. Studies whose results could not be meta-analyzed were excluded. Results: A total of 2643 records were identified; 32 articles evaluating 10 probiotic strains were included in the meta-analyses. Meta-analyses demonstrated the efficacy of Bifidobacterium longum (formerly Bifidobacterium infantis) 35624, Lactobacillus rhamnosus GG, Lactiplantibacillus plantarum 299v (DSM 9843), Saccharomyces cerevisiae CNCM I-3856, and Bacillus coagulans Unique IS2 (MTCC 5260) in improving key IBS symptoms. Meta-analyses also demonstrated that Bacillus coagulans MTCC 5856 improved quality of life for those with IBS. Conflicting results were observed for Saccharomyces boulardii CNCM I-745. Meta-analyses did not demonstrate the efficacy of Escherichia coli Nissle 1917, Lactobacillus gasseri BNR17, or Lactobacillus casei Shirota. Conclusions: Several probiotic strains demonstrated efficacy in the treatment of IBS in meta-analyses of RPCTs.

Chronic neuroinflammation is a key contributor to cognitive decline in neurodegenerative disorders, and improving gut health with probiotics has been proposed as a potential therapeutic strategy. This study investigated the neuroprotective efficacy of Lactobacillus gasseri MG4247 and Lacticaseibacillus rhamnosus MG4644 in a lipopolysaccharide (LPS)-induced mouse model of neuroinflammation-induced cognitive impairment. Compared to mice receiving LPS alone, mice cotreated with LPS and probiotics demonstrated significantly improved spatial memory as measured in the Morris water maze, working memory in the Y-maze, and associative fear learning in the passive avoidance test. These improvements were comparable to LPS model mice cotreated with the clinical acetylcholinesterase inhibitor donepezil. Enzyme-linked immunosorbent assays analysis revealed marked reductions in proinflammatory cytokines (TNF-α, IL-6) in both serum and hippocampus, while histological examination showed reduced neuronal degeneration in the hippocampal CA1 region of LPS model mice cotreated with probiotics. Both probiotics also enhanced gut production of the butyrate, which is known to improve the gut microbial profile and barrier function. Notably, both probiotics also significantly increased brain-derived neurotrophic factor (BDNF) expression and restored phosphorylation of protein kinase B (Akt) and cAMP-response element binding protein (CREB), components of signaling cascade essential for synaptic plasticity, memory formation, and neuronal survival under neuroinflammatory stress. These findings suggest that L. gasseri MG4247 and L. rhamnosus MG4644 mitigate LPS-induced cognitive deficits through anti-inflammatory effects and activation of the Akt/CREB/BDNF pathway. This study supports the potential of probiotics for suppressing neuroinflammation and enhancing cognitive function via neural, immune, and endocrine pathways of the gut-brain axis.

Ulcerative colitis (UC) is a chronic inflammatory disorder marked by epithelial barrier disruption and persistent intestinal inflammation. Despite extensive research, its complex etiology continues to pose therapeutic challenges. Ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation, has recently been implicated in UC pathogenesis. Additionally, the gut microbiota and its metabolites play a pivotal role in maintaining intestinal homeostasis and barrier integrity. This study aimed to investigate the therapeutic potential of a phytotherapeutic agent QCHS to alleviate UC by modulating ferroptosis and the microbiota-metabolome axis, with a particular focus on the role of Lactobacillus gasseri (L. gasseri). A DSS-induced UC mouse model was used to evaluate QCHS efficacy. Gut microbial composition and metabolomic alterations were analyzed via 16S rDNA sequencing and UHPLC-MS/MS. L. gasseri was cultured in vitro to assess the impact of QCHS on its growth. RSL3-induced cell death was modeled in NCM-460 cells and ferroptosis-related changes were examined using transmission electron microscopy, immunohistochemistry, quantitative PCR, and Western blotting. QCHS significantly mitigated DSS-induced ferroptosis in colonic tissues, with L. gasseri identified as a key mediator. Notably, L. gasseri was found to act as a novel ferroptosis inhibitor. In vitro studies confirmed that L. gasseri suppressed RSL3-induced ferroptosis in NCM-460 cells via activation of the GSH/GPX4 pathway. This study provides compelling evidence for the regulatory role of QCHS on the microbiota-metabolome axis and ferroptosis in UC. It also uncovers a novel function of L. gasseri as a ferroptosis inhibitor, offering promising insights into microbiota-targeted and ferroptosis-modulating therapeutic strategies for UC.

Integrated proteomics and metabolomics revealed the influence of ultrasonic cavitation effects on the physicochemical properties and metabolic components during Lactobacillus gasseri JM1 fermentation in soymilk

IntroductionHindlimb immobilization rapidly induces skeletal muscle atrophy by reducing mechanical loading and accelerating proteolytic activity. This atrophy is further exacerbated by inflammatory signaling, which amplifies FOXO3a-driven expression of Atrogin-1 and MuRF1 and suppresses myogenic capacity. Emerging evidence suggests that specific probiotic strains may counteract these catabolic and inflammatory responses, prompting the evaluation of Lactobacillus gasseri CBT LGA2 (LGA2) in this study.MethodsIn the present study, five probiotic strains were screened in C2C12 myotubes and RAW264.7 macrophages to assess anti-proteolytic and anti-inflammatory activities. Whole-genome sequencing was conducted to determine genetic safety and functional gene profiles. In vivo efficacy was evaluated using a hindlimb immobilization mouse model administered with LGA2 (1 × 10⁸ CFU/kg/day, 3 weeks), followed by assessments of muscle mass, grip strength, fiber morphology, and molecular markers.ResultsLGA2 showed the strongest suppression of dexamethasone-induced muscle protein degradation and lipopolysaccharides-induced inflammatory responses among the screened strains. Genomic analysis identified genes related to antioxidant defense, immune modulation, and muscle protection. In immobilized mice, LGA2 significantly improved grip strength, preserved muscle mass, and restored muscle fiber cross-sectional area. Mechanistically, LGA2 maintained FOXO3a phosphorylation, reduced Atrogin-1 and MuRF1 expression, and recovered myogenin and MyHC isoforms (IIa, IIx, IIb). Additionally, LGA2 lowered TNF-α, IL-6, iNOS, and COX-2 levels while restoring IL-10 in muscle and serum.DiscussionThese findings demonstrate that LGA2 mitigates disuse-induced muscle atrophy through coordinated anti-inflammatory, anti-proteolytic, and pro-myogenic mechanisms. Its genomic safety and multifunctional efficacy support LGA2 as a promising probiotic intervention for muscle health.

Assessment of the pathogenic potential (virulence and toxicity) in non-pathogenic bacterial species is a challenge as it relies on methods developed for assessment of species known to be pathogenic. Here, we have applied and evaluated some of these methods on industrially relevant bacteria to differentiate between 'true' virulence factors applying only to pathogens and niche factors being defined as promoting colonization and survival rather than pathogenicity and as being present also in non-pathogenic bacteria. We examined the pathogenicity of 49 strains from 9 industrially relevant bacterial species (Lactobacillus gasseri, Lactobacillus jensenii, Lactobacillus delbrueckii, Lacticaseibacillus rhamnosus, Limosilactobacillus fermentum, Latilactobacillus curvatus, Ligilactobacillus salivarius, Staphylococcus carnosus and Staphylococcus xylosus), including 14 clinical isolates of the same species, through genomic screening and phenotypically through assays established for pathogenic bacteria. The genomes were screened against the Virulence Factor Database (VFDB), and thresholds (>80% nucleotide or protein identity, >70% coverage) provided by the European Food Safety Authority (EFSA) were adopted to differentiate between genes of potential concern and genes of no concern. Core genome analysis was performed to determine whether the clinical isolates were phylogenetically related to the industrial isolates. The genotypic assessment did not reveal the presence of true virulence factors in the examined strains, and in the core genome analysis, the clinical isolates could not be distinguished from the industrial strains. Furthermore, cytotoxicity toward Vero cells, negative impact on Caco-2 cell viability and haemolytic activity on blood agar plates were examined, and none of the tested strains exhibited any activity in these assays. Overall, the results suggest that VFDB screening with the EFSA thresholds can be used to differentiate between true virulence factors and niche factors. Furthermore, the use of phenotypic assays supports the genotypic assessment, albeit expert knowledge is required to interpret the results.

In this study, we evaluated the effects of Lactobacillus gasseri BNR17 supplementation on muscle function, muscle mass, and fat mass in older adults (Average age: 69.1; 23 men and 23 women).A total of 46 participants were administered L. gasseri BNR17 (1 10 10 colonyforming unit/day) once daily for 8 weeks.The following parameters were assessed and compared with baseline values.The total Short Physical Performance Battery score, which consists of standing balance, walking speed, and repeated chair stand tests, increased significantly after supplementation.Handgrip strength also increased, although the change was not statistically significant.In addition, muscle mass-related parameters, including lean body mass, soft lean mass, and leg muscle mass, showed significant increases.At the same time, adiposity-related parameters, including body weight, body fat mass, body mass index, and obesity level, were significantly reduced.These findings suggest that supplementation with the probiotic BNR17 improves physical function and increases muscle mass while reducing body fat and visceral fat in older adults.Therefore, this probiotic may provide potential benefits in the management of sarcopenia and sarcopenic obesity in the elderly by preserving muscle mass and reducing fat mass during weight loss.