Thirty Years of Lactobacillus rhamnosus GG: A Review

Advances in research on the intestinal microbiota in the mechanism and prevention of colorectal cancer (Review)

The intestinal microbiota represents a diverse population that serves a key role in colorectal cancer (CRC) and its treatment outcomes. Advancements in sequencing have revealed notable shifts in microbial composition and diversity among individuals with CRC. Concurrently, animal models have elucidated the involvement of specific microbes such as Lactobacillus fragilis, Escherichia coli and Fusobacterium nucleatum in the progression of CRC. The present review aimed to highlight contributions of intestinal microbiota to the pathogenesis of CRC, the effects of traditional treatments on intestinal microbiota and the potential for microbiota modulation as a therapeutic strategy for CRC.

Genetic and phenotypic stability of Lacticaseibacillus paracasei DG (DSM 34154) over 10 years of industrial production

The commercialization of a probiotic microorganism requires genetic and phenotypic consistency across production lots. However, the large-scale industrial production of probiotic microbial biomasses over years poses a risk of genetic drift, potentially affecting the probiotic's ability to confer health benefits. This study assessed the stability of Lacticaseibacillus paracasei DG (DSM 34154), a commercial probiotic. Seven isolates from different commercial lots over 10 years, one 8-year-old laboratory subculture, one isolate from human feces, and the DG strain deposited at DSMZ were analyzed. Shotgun and PacBio sequencing were combined to obtain the complete genome of the 10 isolates. Comparative analysis showed that the seven commercial isolates had identical genomes, differing from the DSMZ isolate by one synonymous transition and one non-synonymous transversion. The laboratory subculture strain had two additional mutations. Phenotypic analyses, including antibiotic resistance, carbohydrate fermentation profile, survival to simulated gastrointestinal transit, immunomodulatory capacity, and radical scavenging ability, found no significant differences among isolates. Overall, this study demonstrates the substantial equivalence of L. paracasei DG over 10 years of industrial production, indicating that the current industrial practices help prevent genome alterations that could compromise probiotic performance. Similar studies should be part of continuous monitoring and quality control measures for the probiotic products on the market.IMPORTANCEThe genetic and functional stability of probiotic strains during years of industrial production is essential but has not been clearly demonstrated for many strains. This study shows that careful industrial practices can maintain the genetic integrity and functionality of probiotics. Using advanced genome sequencing and detailed laboratory tests, we confirmed that the probiotic Lacticaseibacillus paracasei DG (DSM 34154) has remained stable over a decade of production, consistently delivering its health-promoting properties. These findings support the quality and reliability of probiotic products, fostering consumer trust and highlighting the importance of continuous monitoring in probiotic manufacturing to sustain quality assurance.

The insertion of the inverted repeat of an insertion sequence (IS) element from Lacticaseibacillus rhamnosus changes the host range and stability of pGK12, a shuttle vector for lactic acid bacteria

Insertion sequences (ISs) are key components of most bacterial genomes and play a crucial role in bacterial mutagenesis. In this study, we observed the insertion of an IS element, ISLrh, from the Lacticaseibacillus rhamnosus M1 genome into plasmid pGK12, resulting in the generation of a new plasmid, pTRK829. This insertion enabled pTRK829 to replicate in hosts previously incompatible with pGK12, including L. rhamnosus M1, L. rhamnosus GG (LGG), Lacticaseibacillus casei ATCC 393, and Lacticaseibacillus paracasei ATCC 25598. However, the ISLrh-inserted plasmid, pTRK829, was unstable and underwent a spontaneous deletion, resulting in a smaller and more stable variant, pTRK830, which retained ISLrh. Characterization of pTRK829 and pTRK830 across several host strains showed that ISLrh insertion led to a dramatic alteration in host range and impacted plasmid stability and copy number. Sequence and functional analysis of pTRK830 revealed that the terminal inverted repeats (IRs) of the inserted ISLrh and its insertion location were essential for plasmid replication in LGG. Finally, pTRK830 was successfully used as an expression vector for heterologous β-glucuronidase expression in LGG, L. casei ATCC 393, and L. paracasei ATCC 25598. In conclusion, this study demonstrated that the insertion of the IRs from ISLrh at a specific location can directly change the host range and stability of pGK12. Furthermore, we also demonstrated the potential of pTRK830 as a new cloning and expression vector for genetically intractable lactobacilli.

IMPORTANCE

This study highlights the significant impact of insertion sequence (IS) elements on plasmid replication in lactobacilli. The spontaneous integration of an IS element from the Laticaseibacillus rhamnosus genome into plasmid pGK12 not only expands its host range in previously incompatible strains but also changes plasmid stability and copy number. This expansion of the plasmid's host range is crucial for developing versatile genetic tools across diverse lactobacilli species. Additionally, the stable plasmid variant of pGK12 with the IS element insertion offers a valuable tool for cloning and gene expression in lactobacilli. These findings enhance our understanding of plasmid-IS element interactions and may provide insight into a new method to expand the host range of existing plasmids.

Probiotics improve lung function and QOL in participants with exposure to fine particulate matter air pollution: a randomized, double-blind, placebo-controlled clinical trial

Background: Probiotics have been reported to alleviate pulmonary inflammation through the gut-lung axis. However, their effects on PM2.5-induced toxic reactions have not yet been well studied. Objective: This study aims to investigate the effects of probiotics on lung function and quality of life in participants exposed to PM2.5, as well as to explore the potential mechanisms underlying these effects. Methods: 120 volunteers were randomly assigned in a double-blind manner to receive either a placebo or 2.5 × 109 cfu g-1 LGG probiotics once daily for four consecutive weeks, with a follow-up period of 6 months. An analysis of covariance was conducted for data statistics, using PM2.5 exposure and baseline measurements as covariates. Least squares means and their 95% confidence intervals were calculated to explore the effect of PM2.5 exposure on changes in the intestinal microbiota. A mixed linear model analysis was used to construct a model with baseline values and PM2.5 exposure as covariates to analyse the effects of PM2.5 on SF-36, COOP/WONCA charts, and lung function, and the intervention effect of LGG on these parameters. Results: 120 participants were included. Probiotic intervention demonstrated benefits in the Shannon index and β diversity. After the probiotic intervention, the scores of quality-of-life charts increased during the follow-up period. The pulmonary function indicators, including FEV1, FEF50%, and FEF75%, were statistically different from those in the placebo group. Conclusion: Probiotic intervention can reshape the gut microbiota, offering potential benefits for improving the quality of life in participants chronically exposed to PM2.5.

Probiotic effects of Clostridium cellabutyricum YQ-FP-027T on DSS-induced colitis mice via modulating gut microbiota and preventing inflammation

Butyrate-producing Clostridium spp. play fundamental roles in maintaining gut microbiota homeostasis by producing short-chain fatty acids. However, exploration of the strain resources and their probiotic effects remains limited. In previous work, a novel species of butyrate-producing Clostridium, Clostridium cellabutyricum YQ-FP-027T, was isolated from the pit mud of Chinese Baijiu brewing, which possesses antibacterial activities by modulating gut microbiota. The present study investigated the probiotic effects of YQ-FP-027T on mice with dextran sulfate sodium (DSS)-induced colitis and the underlying mechanism. The results showed that the mice treated with YQ-FP-027T exhibited lower disease activity index (DAI), recovered weight loss, and reduced colon shortening. Regarding gut microbial composition, these mice showed increased Shannon and Species richness observed (Sobs) indexes and a rising abundance of beneficial bacteria such as Akkermansia and Alistipes. Additionally, the expression levels of inflammatory factors Interleukin-1 beta (IL-1β), Interleukin-6 (IL-6), and Tumor Necrosis Factor-alpha (TNF-α) were suppressed, while those of anti-inflammatory factor Interleukin-10 (IL-10) and the cathelicidin-related antimicrobial peptide (CRAMP) were enhanced under YQ-FP-027T treatment. These results suggest that YQ-FP-027T holds potential as a promising probiotic against DSS-induced colitis via optimizing gut microbial community structure and modulating gut immune microenvironment.

Lactobacillus rhamnosus GG Combined with Metformin Alleviates Alcohol-Induced Liver Inflammation in Mice by Maintaining the Intestinal Barrier and Regulating Treg/Th1 Cells

Disturbances of the intestinal barrier enabling bacterial translocation exacerbate alcoholic liver disease (ALD). Lactobacillus rhamnosus GG (LGG) has been shown to exert beneficial effects in gut dysbiosis and chronic liver disease. The current study assessed the combined effects of LGG and metformin, which play roles in anti-inflammatory and immunoregulatory processes, in alcohol-induced liver disease mice. A diet comprising 5% alcohol for 4 weeks was employed to develop an alcohol-induced liver injury model. Mice were orally administered LGG, metformin, or their combination on alternate days. Tight junction (TJ) proteins, gut microbiome composition, inflammatory cytokines, Jun N-terminal kinase (JNK), and p38 signals were assessed. When compared with treatment with LGG or metformin alone, combined LGG and metformin treatment substantially lowered the symptoms of inflammation, steatosis, and elevated liver enzymes caused by alcohol administration. Combination treatment significantly improved intestinal microecology, evidenced by the recovery of intestinal flora, TJ proteins, and intestinal villi. Combination treatment reduced hepatic inflammation by blocking p38 and JNK phosphorylation. The combination of LGG and metformin corrected immune-response dysregulation and improved ALD by enhancing the intestinal microbiome, restoring mucosal barrier integrity, modulating immune function, and decreasing liver injury. These results provide information for the development of intestinal microbiota-based preventive and therapeutic agents against ALD.

Harnessing the power of breast milk: how Lactiplantibacillus plantarum FN029 from rural western China mitigates severe atopic dermatitis in mice through retinol metabolism activation

Tongwei and Wuxi represent a rural county in western China and an industrialized city in the east, respectively. The study compared breast milk and the corresponding infant gut microbiota from 35 healthy mothers in Tongwei and 28 in Wuxi, uncovering significant differences in microbial alpha and beta diversity. A unique strain, Lactiplantibacillus plantarum FN029, characteristically transmitted from breast milk to the infant gut in Tongwei, was identified. Oral administration of FN029 to weaned BALB/c mice significantly alleviated atopic dermatitis severity caused by calcipotriol and ovalbumin. This reduction was paralleled by a decrease in mast cells and eosinophils in ear tissue and reduced levels of IL-4, IL-12, IL-33, IFN-γ, the IL-4/IFN-γ ratio, and IgE in plasma, along with an upsurge in regulatory T cells in the spleen. RNA sequencing revealed that FN029 activated the retinol metabolism pathway and the Wnt signaling pathway, enhancing immature dendritic cells and regulatory T cells. Metabolomics analysis indicated an increase in retinyl beta-glucuronide, a biomarker of vitamin A reserves. The mRNA expression of retinol-metabolizing enzymes was inversely related to the IL-4/IFN-γ ratio. FN029 also altered ileum microbiota without a direct link to atopic dermatitis improvement. In conclusion, L. plantarum FN029, a probiotic from Tongwei breast milk, fostered T regulatory cell conversion and immune balance by activating the retinol pathway, thereby improving severe atopic dermatitis in mice.

The Neurobehavioral Impact of Zinc Chloride Exposure in Zebrafish: Evaluating Cognitive Deficits and Probiotic Modulation

Zinc contamination in aquatic environments has become a growing concern due to its potential to bioaccumulate and induce neurotoxic effects in aquatic organisms. As an essential trace element, zinc plays a crucial role in various physiological processes, but excessive exposure can disrupt the gut-brain axis, leading to cognitive and behavioral impairments. Recent studies have suggested that probiotics may offer protective effects against environmental neurotoxins by modulating the gut microbiota and associated neurological functions. The zebrafish (Danio rerio) has emerged as a valuable model organism for studying the biological mechanisms underlying neurotoxicity and potential therapeutic interventions. This study aimed to assess the effects of probiotics on cognitive impairments induced by zinc chloride (ZnCl2) exposure in zebrafish. Specifically, zebrafish were exposed to ZnCl2 at concentrations of 0.5 mg/L and 1.0 mg/L for 96 h, followed by a 7-day post-exposure period to probiotics (Bifidobacterium longum, Bifidobacterium animalis lactis, Lactobacillus rhamnosus). ZnCl2 exposure at these concentrations is already known to induce behavioral and neuromotor deficits resembling Alzheimer's disease-like symptoms in zebrafish models, making it a suitable model for evaluating the neuroprotective potential of probiotics. Behavioral assessments including sociability tests along with short- and long-term memory evaluations were conducted using EthoVision XT 16 software. Memory tests demonstrated that ZnCl2 exposure impaired cognitive functions, while probiotic treatment did not significantly ameliorate these deficits. In the social behavior test, ZnCl2 at 0.5 mg/L resulted in a marked decrease in sociability, whereas exposure to 1.0 mg/L did not induce significant changes. However, post-exposure probiotic administration following ZnCl2 intoxication at 1.0 mg/L exhibited an anxiolytic effect on zebrafish. These findings suggest that probiotics may exhibit partial neurobehavioral benefits following zinc chloride-induced toxicity, particularly in mitigating anxiety-like behaviors rather than cognitive deficits. Further investigations are needed to elucidate the precise mechanisms by which probiotics interact with the gut-brain axis in the context of heavy metal neurotoxicity.

A comprehensive approach, based on the use of Caenorhabditis elegans, mouse, and human models, elucidates the impact of Lactiplantibacillus plantarum TWK10 on exercise performance and longevity

The functionality of probiotics is highly influenced by culture and processing conditions, making batch stability validation through human or mouse trials impractical. Here, we employed a comprehensive approach using Caenorhabditis elegans, mouse and human models to elucidate the beneficial effects of Lactiplantibacillus plantarum TWK10 (TWK10). In C. elegans, TWK10 administration significantly prolonged lifespan by 26.1 ± 11.9 % (p < 0.05), enhanced locomotion (p < 0.01) and muscle mass (p < 0.001), elevated glycogen storage (p < 0.05), and reduced lipid accumulation (p < 0.001), outperforming Lacticaseibacillus rhamnosus GG and L. plantarum type strain ATCC 14917T. We also confirmed the equivalence of laboratory-prepared and mass-produced TWK10 in ergogenic efficacy using C. elegans assay. In mice, oral administration of mass-produced TWK10 significantly enhanced exercise performance and glycogen storage in muscle and liver in a dose-dependent manner. In a clinical study involving healthy male adults, significant improvements in grip strength (1.1-fold, p < 0.01) and exhaustion time (1.27-fold, p < 0.01), and significant reductions in circulating lactate and ammonia levels were observed in the TWK10 group (1 × 1010 colony-forming unit/day) compared to the control group. Both humans and mice receiving mass-produced TWK10 showed improved body composition with increased muscle mass and reduced fat mass. In conclusion, TWK10 demonstrates superior longevous and ergogenic effects in C. elegans compared to reference strains. The consistent ergogenic efficacy of mass-produced TWK10 across C. elegans, mice, and humans, highlights the utility of C. elegans as a reliable model for probiotic research and industrial application.

Gut microbiome and liver diseases

Symbiotic microbiota plays a crucial role in the education, development, and maintenance of the host immune system, significantly contributing to overall health. Through the gut-liver axis, the gut microbiota and liver have a bidirectional relationship that is becoming increasingly evident as more research highlights the translocation of the gut microbiota and its metabolites. The focus of this narrative review is to examine and discuss the importance of the gut-liver axis and the enterohepatic barrier in maintaining overall health. Additionally, we emphasize the crucial role of the gut microbiome in liver diseases and explore potential therapeutic strategies for liver diseases by manipulating the microbiota.

Probiotic-Derived P8 Protein: Promoting Proliferation and Migration in Stem Cells and Keratinocytes

Probiotics exert various effects on the body and provide different health benefits. Previous reports have demonstrated that the P8 protein (P8), isolated from Lactobacillus rhamnosus, has anticancer properties. However, its efficacy in stem cells and normal cells has not been reported. In this study, the effect of P8 on cell proliferation and wound healing was evaluated, investigating its underlying mechanism. Based on scratch assay results, we demonstrated that P8 treatment significantly increases wound healing by activating the cell cycle and promoting stem cell stemness. Cellular mechanisms were further investigated by culturing stem cells in a medium containing Lactobacillus-derived P8 protein, revealing its promotion of cell proliferation and migration. Also, it is found that P8 enhances the expression of stemness markers, such as OCT4 and SOX2, along with activation of the mitogen-activated protein kinase (MAPK) signaling and Hippo pathways. These results indicate that P8 can promote cell growth by increasing stem cell proliferation, migration, and stemness in a manner associated with MAPK and Hippo signaling, which could contribute to the increased wound healing after P8 treatment. Furthermore, P8 could promote wound healing in keratinocytes by activating the MAPK signaling pathways. These results suggest that P8 might be a promising candidate to enhance stem cell culture efficiency by activating cell proliferation, and enhance therapeutic effects in skin diseases.

Lacticaseibacillus rhamnosus: An Overview of the Viability in Fruit and Vegetable Juices and Their Potential Effects on Human Health

Consumer demand for health-enhancing foods is growing, with plant-based probiotic foods gaining prominence. Fruit and vegetable juices offer promising matrices for delivering probiotic strains due to their rich bioactive compound content, which holds nutritional and technological significance. Lacticaseibacillus rhamnosus is commonly employed in viability studies, offering both technological benefits and potential health advantages for consumers. The main databases were searched to bring together a compilation of studies that assessed the feasibility and technological parameters of fruit and vegetable juices enriched with Lacticaseibacillus rhamnosus. In addition, this review aims to analyze promising points, gaps, and challenges in the development of these products, such as the relationship between the technological aspect of manufacturing this type of food and impacts on human health. The strain most used in the studies was Lacticaseibacillus rhamnosus GG. More than half of the formulations maintained viability above 8 log CFU/mL. Low pH, high dissolved oxygen concentrations, and low free amino acid concentrations can all be obstacles to preserving viability in fruit and vegetable juices. Various techniques, including microencapsulation, prebiotic supplementation, and pH adjustments, have been employed by researchers to achieve more favorable results. Despite numerous meta-analyses on supplementation alone, human studies on the consumption of probiotic-enriched juices remain scarce, which highlight the need for more research.

Construction, characterization, and properties of a probiotic delivery system based on oxidized high amylose starch

This study demonstrates the preparation of oxidized high amylose starch (OHAS) and its effect on the survival and release of Lacticaseibacillus rhamnosus GG (LGG) in the gastrointestinal tract when combined with sodium alginate (SA). OHAS with different degrees of oxidation was combined with SA, and through rheological analysis, an SA/OHAS composite with good viscoelasticity, stable structure, and favorable for probiotic colonization was selected as the probiotic carrier. Specifically, SA/OHAS showed a good encapsulation efficiency of 46.21 % and maintained good viability after gastric juice digestion, with a surviving probiotic count of 5.87 × 106 CFU/mL. It exhibits good release efficiency in intestinal fluid, with a release rate reaching 85.67 % within 2 h. In vivo intestinal transit visualization evaluation after feeding mice showed that SA/OHAS could effectively prolong the retention time of probiotics in the intestine. In vitro experiments further proved that SA/OHAS could significantly enhance the resistance of probiotics in gastric juice and provide a targeted release for intestine-specific delivery. These results provide a promising strategy for the delivery system of SA/OHAS encapsulated probiotics in oral food applications.

Genome Mining and Characterization of Two Novel Lacticaseibacillus rhamnosus Probiotic Candidates with Bile Salt Hydrolase Activity

Bile salt hydrolase (BSH; EC 3.5.1.24) is the microbial enzyme that catalyzes the conversion of primary bile acids (BAs) into secondary ones, promoting microbial adaptation and modulating several host's biological functions. Probiotics with BSH activity are supposed to survive harsh intestinal conditions and exert a cholesterol-lowering effect. Here, Lacticaseibacillus rhamnosus strains (VB4 and VB1), isolated from the vaginal ecosystem, were submitted to a genomic survey, in vitro BSH activity, and BAs tolerance assay to unravel their probiotic potential as BAs modulators. The draft genomes of Lcb. rhamnosus VB4 and VB1 strains comprised 2769 and 2704 CDSs, respectively. Gene annotation revealed numerous strain-specific genes involved in metabolism and transport, as well as in DNA recombination. Each strain harbors a single bsh gene, encoding a C-N amide hydrolase, which conserved the essential residues required in the BSH core site. According to the results, compared to VB1, the VB4 strain tolerated better BAs stress and was more active in deconjugating BAs. However, BAs stress increased the bsh gene transcription in the VB1 strain but not in the VB4 strain, suggesting a partially nonlinear relationship between BSH activity and gene expression. In conclusion, despite the complexity of the BSH transcriptional system, the results support the VB4 strain as a promising BAs-deconjugating probiotic candidate.

Review: Gut microbiota: Therapeutic targets of ginseng polysaccharides against multiple disorders

As biological macromolecules, ginseng polysaccharides (GP) are often difficult to be directly absorbed through the intestinal cell membrane. It has been found that it can regulate gut microbiota by acting as a prebiotic, and then play a therapeutic role in some diseases, such as diarrhea, tumour, diabetic, dementia, obesity. With the deepening of research, we found that the role played by GP as a prebiotic cannot be ignored. Not only that, it can also affect the immunity and the metabolism and absorption of ginsenosides to play a synergistic role. Overall, GP can regulate the diversity of gut microbiota, which in turn affects the synthesis of secondary metabolites. GP also promotes the transformation of ginsenosides, leading to improved absorptivity of these compounds. This review aims to provide a deeper understanding of how GP interacts with the gut microbiota in various disorders and the transformation of ginsenosides. By exploring these interactions, we can gain valuable insights into the potential benefits of GP in managing different health conditions and enhancing the bioavailability of ginsenosides.

Impact of a Symbiotic Mixture on Moderate-to-severe Diverticular Disease of the Colon

BACKGROUND

Microbial imbalance is thought to play a role in the pathogenesis of Diverticular Disease (DD).

OBJECTIVE

We aimed to assess the efficacy of a symbiotic mixture (Prolactis GG Plus®) in the treatment of moderate to severe DD, scored according to the Diverticular Inflammation and Complication Assessment (DICA) classification.

METHODS

A retrospective study was conducted enrolling the following patients: at the first diagnosis of DD; in whom DD was diagnosed with colonoscopy and scored according to DICA classification; treated with Prolactis GG Plus® two times/daily for 2 consecutive months; in whom the severity of the abdominal pain was scored with a 10-points visual-analogue scale (VAS) at baseline and the end of follow-up; in whom fecal calprotectin (FC) was assessed at baseline and the end of follow-up as μg/g.

RESULTS

Twenty-four patients were identified (10 males, 14 females; 16 as DICA 2, and 8 as DICA 3). Prolactis GG Plus® decreased the severity of abdominal pain both in DICA 2 (p =0.02) and DICA 3 patients (p =0.01), while FC decreased significantly in DICA 2 (p <0.02) but not in DICA 3 (p =0.123) patients. Acute diverticulitis occurred during the follow-up in two DICA 3 patients but none DICA 2 patients. Add-on therapy was required by eight DICA 2 (50%) and six DICA 3 patients (75%).

CONCLUSION

In newly diagnosed patients with DD, the symbiotic mixture Prolactis GG Plus® can be a potential treatment for moderate (DICA 2) DD as a single treatment.

Valorization of Coffee Cherry By-Products Through Fermentation by Human Intestinal Lactobacilli in Functional Fermented Milk Beverages

During coffee production, the removal and disposal of the coffee bean-surrounding layers pose an environmental problem. In this work, we examined the effects of several aqueous coffee cherry extracts on the growth and metabolism, biofilm formation, antioxidant capacity and antimicrobial activity of six lactobacilli from the INIA collection and a commercial probiotic Lactobacillus rhamnosus GG strain. Growth medium supplementation with different coffee cherry extracts (at 40%) stimulated strain growth and metabolism. The ground cherry pulp extract (CPE) with the highest total polyphenol content was selected for further use. This CPE contained alkaloids, phenolic acids and flavonoids. Upon CPE supplementation, some strains significantly (p < 0.01) increased biofilm formation, while all strains increased antioxidant capacity and antimicrobial activity. After preliminary tests, we developed three bifunctional dairy products, containing 20% CPE and fermented with strains INIA P495, INIA P708 or GG. These strains maintained high levels after manufacture, refrigerated storage, and throughout an in vitro procedure mimicking gastrointestinal tract conditions. Compared to controls, CPE-containing products showed increased levels of total polyphenol compounds, antioxidant capacity and antimicrobial activity, together with positive sensory characteristics. CPE and these selected strains could thus be used to elaborate innovative functional fermented milk products.

Environmental Changes Driving Shifts in the Structure and Functional Properties of the Symbiotic Microbiota of Daphnia

Symbiotic microbiota significantly influence the development, physiology, and behavior of their hosts, and therefore, they are widely studied. However, very few studies have investigated the changes in symbiotic microbiota across generations. Daphnia magna originating from the Qinghai-Tibetan Plateau were cultured through seven generations in our laboratory, and the symbiotic microbiota of D. magna were sequenced using a 16S rRNA amplicon to analyze changes in the structure and functional properties of the symbiotic microbiota of D. magna from a harsh environment to an ideal environment. We detected substantial changes in the symbiotic microbiota of D. magna across generations. For example, the genus Nevskia, a member of the gamma-subclass Proteobacteria, had the highest abundance in the first generation (G1), followed by a decrease in abundance in the fourth (G4) and seventh (G7) generations. The gene functions of the microbiota in different generations of D. magna also changed significantly. The fourth generation was mainly rich in fatty acyl-CoA synthase, acetyl-CoA acyltransferase, phosphoglycerol phosphatase, etc. The seventh generation was mainly rich in osmotic enzyme protein and ATP-binding protein of the ABC transport system. This study confirms that the alterations in the structure and functional properties of the symbiotic microbiota of D. magna under changing environments are typical responses of D. magna to environmental changes.

Lactobacillus reuteri or Lactobacillus rhamnosus GG intervention facilitates gut barrier function, decreases corticosterone and ameliorates social behavior in LPS-exposed offspring

Probiotic therapy with Lactobacillus reuteri and Lactobacillus rhamnosus (LGG) demonstrates potential as an adjunctive treatment for autism spectrum disorder (ASD). In a rat model of ASD induced by lipopolysaccharide (LPS) injection during pregnancy, we evaluated the effects of these probiotics on offspring. Administration of L. reuteri or LGG for three weeks post-birth improved social deficits and reduced anxiety in LPS-exposed rats. Additionally, probiotics significantly modified short-chain fatty acid profiles, increasing butyric acid levels and decreasing propionic acid levels. They also enhanced colonic barrier integrity by upregulating tight junction proteins, including ZO-1, Occludin, and Claudin4. RNA sequencing identified differential gene expression in pathways related to inflammation, the HPA axis, and reactive oxygen species metabolism, with NADPH oxidase 1 (NOX1) emerging as a crucial gene. Validation studies confirmed that Lactobacillus strains reduced inflammatory cytokines, inhibited corticosterone secretion, increased antioxidant levels, and suppressed the NF-κB/NOX1 pathway. In an H2O2-induced oxidative stress model using Caco-2 cells, pre-treatment with L. reuteri, LGG, or NF-κB inhibitors enhanced cellular antioxidants, inhibited NF-κB/NOX1 activation, and improved barrier function. Overall, L. reuteri and LGG administration improved social behavior, bolstered colonic barrier function, and mitigated HPA axis overactivation in LPS-exposed rats, while also alleviating oxidative stress in the colon and Caco-2 cells. These findings suggest that L. reuteri and LGG have substantial clinical potential for ASD treatment by targeting multiple pathophysiological mechanisms, including inflammation, HPA axis dysregulation, and oxidative stress, thereby presenting a promising adjunctive therapeutic strategy for enhancing social behavior and gut health in ASD.

Lactobacillus rhamnosus GG Regulates Host IFN-I Through the RIG-I Signalling Pathway to Inhibit Herpes Simplex Virus Type 2 Infection

Numerous recent studies have demonstrated that the commensal microbiota plays an important role in host immunity against infections. During the infection process, viruses can exhibit substantial and close interactions with the commensal microbiota. However, the associated mechanism remains largely unknown. Therefore, in this study, we explored the specific mechanisms by which the commensal microbiota modulates host immunity against viral infections. We found that the expression levels of type I interferon (IFN-I) and antiviral priming were significantly downregulated following the depletion of the commensal microbiota due to treatment with broad-spectrum antibiotics (ABX). In addition, we confirmed a unique molecular mechanism underlying the induction of IFN-I mediated by the commensal microbiota. In vivo and in vitro experiments confirmed that Lactobacillus rhamnosus GG (LGG) can suppress herpes simplex virus type 2 (HSV-2) infection by inducing IFN-I expression via the retinoic acid-inducible gene-I (RIG-I) signalling pathway. Therefore, the commensal microbiota-induced production of IFN-I provides a potential therapeutic approach to combat viral infections. Altogether, understanding the complexity and the molecular aspects linking the commensal microbiota to health will help provide the basis for novel therapies already being developed.

The Immunomodulatory Effects and Applications of Probiotic Lactiplantibacillus plantarum in Vaccine Development

Lactiplantibacillus plantarum (previously known as Lactobacillus plantarum) is a lactic acid bacterium that exists in various niches. L. plantarum is a food-grade microorganism that is commonly considered a safe and beneficial microorganism. It is widely used in food fermentation, agricultural enhancement, and environmental protection. L. plantarum is also part of the normal flora that can regulate the intestinal microflora and promote intestinal health. Some strains of L. plantarum are powerful probiotics that induce and modulate the innate and adaptive immune responses. Due to its outstanding immunoregulatory capacities, an increasing number of studies have examined the use of probiotic L. plantarum strains as natural immune adjuvants or alternative live vaccine carriers. The present review summarizes the main immunomodulatory characteristics of L. plantarum and discusses the preliminary immunological effects of L. plantarum as a vaccine adjuvant and delivery carrier. Different methods for improving the immune capacities of recombinant vector vaccines are also discussed.

Evaluation of Probiotic Potential and Functional Properties of Lactobacillus Strains Isolated from Dhan, Traditional Algerian Goat Milk Butter

Goat milk butter, locally known as "Dhan", from the Sfisfa region of Algeria, holds significant cultural and economic value. This study investigates the probiotic properties of lactic acid bacteria (LAB) present in Dhan, focusing particularly on Lactobacillus strains. Molecular identification using 16S rRNA revealed a dominance of Levilactobacillus brevis and Lactiplantibacillus plantarum, forming a substantial part of the bacterial profile. Three LAB isolates (DC01-A, DC04, and DC06) were selected from fresh samples, and rigorous analyses were performed to evaluate their probiotic properties. Safety assessments confirmed the absence of gelatinase, DNase, and haemolytic activities in all isolates. The isolates demonstrated high tolerance to bile salts and acidic conditions, along with the ability to survive simulated gastrointestinal digestion. Notably, strain DC06 exhibited exceptional survival at low pH (1.5) and high bile salt concentrations (0.15-0.3%). All isolates showed substantial growth in MRS medium with 2% phenol, although growth was significantly decreased at 5% phenol. Furthermore, our strains exhibited high adhesion rates to various solvents, demonstrating their potential for strong interaction with cell membranes. Specifically, adhesion to chloroform was observed at 98.26% for DC01-A, 99.30% for DC04, and 99.20% for DC06. With xylene, the adhesion rates were 75.94% for DC01-A, 61.13% for DC04, and 76.52% for DC06. The LAB strains demonstrated impressive growth in ethanol concentrations up to 12%, but their tolerance did not exceed this concentration. They also exhibited robust growth across temperatures from 10 °C to 37 °C, with strains DC04 and DC06 able to proliferate at 45 °C, though none survived at 50 °C. Additionally, the isolates showed significant resistance to oxidative stress induced by hydrogen peroxide (H2O2) and displayed medium to high autolytic activity, with rates of 50.86%, 37.53%, and 33.42% for DC01-A, DC04, and DC06, respectively. The cell-free supernatant derived from strain DC04 exhibited significant antimicrobial activity against the tested pathogens, while strain DC06 demonstrated moderate antioxidant activity with the highest DPPH scavenging rate at 68.56%, compared to the probiotic reference strain LGG at 61.28%. These collective findings not only suggest the probiotic viability of LAB strains found in Dhan but also highlight the importance of traditional food practises in contributing to health and nutrition. Consequently, this study supports the potential of traditional Dhan butter as a functional food and encourages further exploration of its health benefits.

Phosphorylation-dependent immunomodulatory properties of B.PAT polysaccharide isolated from Bifidobacterium animalis ssp. animalis CCDM 218

A wide range of articles describe the role of different probiotics in the prevention or treatment of various diseases. However, currently, the focus is shifting from whole microorganisms to their easier-to-define components that can confer similar or stronger benefits on the host. Here, we aimed to describe polysaccharide B.PAT, which is a surface antigen isolated from Bifidobacterium animalis ssp. animalis CCDM 218 and to understand the relationship between its structure and function. For this reason, we determined its glycerol phosphate-substituted structure, which consists of glucose, galactose, and rhamnose residues creating the following repeating unit: To fully understand the role of glycerol phosphate substitution on the B.PAT function, we prepared the dephosphorylated counterpart (B.MAT) and tested their immunomodulatory properties. The results showed that the loss of glycerol phosphate increased the production of IL-6, IL-10, IL-12, and TNF-α in bone marrow dendritic cells alone and after treatment with Lacticaseibacillus rhamnosus GG. Further studies indicated that dephosphorylation can enhance B.PAT properties to suppress IL-1β-induced inflammatory response in Caco-2 and HT-29 cells. Thus, we suggest that further investigation of B.PAT and B.MAT may reveal distinct functionalities that can be exploited in the treatment of various diseases and may constitute an alternative to probiotics.

Akkermansia muciniphila: new insights into resistance to gastrointestinal stress, adhesion, and protein interaction with human mucins through optimised in vitro trials and bioinformatics tools

According to the FAO/WHO guidelines, selection of probiotics requires the assessment of survival under gastrointestinal stress and adhesion to human epithelial cells. These attributes were evaluated on Akkermansia muciniphila ATCC BAA-835 simulating the gastrointestinal transit (GIT) immediately followed by adhesion to human intestinal cell lines (CaCo2, HT-29, and HT-29-MTX) as an alternative approach to in vitro methods performed with fresh cells in each trial. The survival rate after GIT, as determined by plate counts and fluorescent probes, was significantly higher for A. muciniphila (about 8 Log CFU/mL) than for the probiotic Lacticaseibacillus rhamnosus GG ATCC 53103 (about 3 Log CFU/mL). The use of Live/Dead assay highlighted that A. muciniphila forms cell aggregates in the gastric phase as protective mechanism, explaining its high viability in the intestine. The rate of adhesion to human cell lines was always lower for strains tested after simulated GIT than for strains that did not undergo simulated GIT. Akkermansia muciniphila exhibited significantly higher adhesion than Lbs. rhamnosus GG, particularly to the mucus-secreting HT-29-MTX cells across a range of concentrations (2-8 Log CFU/mL). Finally, the bioinformatic analysis of A. muciniphila proteome confirmed the Amuc_1434 as a potential factor in binding to the human MUC2 protein.

Lactobacillus rhamnosus GG attenuates depression-like behaviour and cognitive deficits in chronic ethanol exposure mice by down-regulating systemic inflammatory factors

Ethanol can directly or indirectly lead to cognitive and mental disorders. The long-term intake of alcohol can directly affect the distribution of gut microbiota. Lactobacillus rhamnosus GG (LGG) is a natural bacterium isolated from healthy human intestines that has the function of preventing cytokine-induced cell apoptosis and protecting cell barriers. However, the regulatory effect of LGG on cognitive and mental disorders caused by chronic ethanol exposure (CEE) is still unclear. In this study, we established a CEE mouse model through free alcohol consumption and added LGG or antibiotics in the later stages of the model. Sequencing analysis of the 16S rRNA gene showed that CEE resulted in a decrease in the abundance and diversity of mouse gut microbial communities accompanied by alterations in the relative abundance of multiple enterobacterial genera. The use of LGG and antibiotics alleviated the depression-like behaviour and cognitive impairment of CEE-induced mice, reduced expression of inflammatory factors such as interleukin (IL)-6, IL-1β and tumour necrosis factor (TNF)-α in the ileum, serum and brain and increased the expression of synaptophysin (SYN), postsynaptic density protein-95 (PSD-95) and brain-derived neurotrophic factor (BDNF) in the hippocampus. Together, LGG can alleviate depression-like behaviour caused by CEE in mice while also improving cognitive and memory functions through reducing peripheral and nervous system inflammation factors and balancing gut microbiota.

Limosilactobacillus allomucosae sp. nov., a novel species isolated from wild boar faecal samples as a potential probiotic for domestic pigs

Six strains, WILCCON 0050, WILCCON 0051, WILCCON 0052, WILCCON 0053, WILCCON 0054, WILCCON 0055T, were isolated from four different faecal samples of wild boars on Pulau Ubin, Singapore, Singapore. Based on core genome phylogenetic analysis, the six strains formed a distinct clade within the genus Limosilactobacillus (Lm.), with the most closely related type strain being Lm. mucosae DSM 13345T. The minimum ANI, dDDH, and AAI values within these six strains were 97.8%, 78.8%, and 98.6%, respectively. In contrast, the ANI, dDDH, and AAI values with Lm. mucosae DSM 13345T were lower, ranging between 94.8-95.1%, 57.1-59.0%, and 95.9-97.0%, respectively. While ANI and AAI were close to the thresholds of 95% and 97% for bacterial species delineation, respectively, dDDH was significantly lower than the threshold value of 70%. Based on our phylogenomic, phenotypic and chemotaxonomic analyses, we propose a novel species with the name Limosilactobacillus allomucosae sp. nov., with WILCCON 0055T (DSM 117632T = LMG 33563T) as the designated type strain. In vitro investigations revealed the strains' ability to break down raffinose-family oligosaccharides, and to utilize prebiotics such as xylo-oligosaccharides and galacturonic acid, thereby enhancing fibre digestion and nutrient absorption. Moreover, strong auto-aggregation properties, as well as resistance to low pH and porcine bile were observed, suggesting their potential survival and persistence during passage through the gut. The high bile tolerance of these strains appears to be attributed to their ability to deconjugate a wide range of conjugated bile compounds. In silico analysis indicated a strong potential for mucin-binding activity, which aids their colonization in the gut. These characteristics indicate the potential suitability of strains of Lm. allomucosae as probiotics for domestic pigs.

Utilization of Probiotic-Derived Extracellular Vesicles as Postbiotics and Their Role in Mental Health Therapeutics

As consumers become more interested in healthier lifestyles, the global functional food market is expanding. Probiotics have gained attention because of their numerous health benefits to the host and may even treat various pathological conditions. Probiotics interact with host cells, and particularly, probiotics-derived extracellular vesicles (PEVs) are key factors in the health benefits of probiotics. Additionally, extracellular vesicles are nano-scaled lipid-bilayer particles that carry various biological molecules, indicating potential as new postbiotics that can provide the same health benefits as probiotics while complementing the side effects associated with probiotics. The importance of mental health care is becoming increasingly prominent considering societal conditions, such as the recent aging population and the coronavirus disease 2019 pandemic. However, the response to mental health issues among modern individuals is insufficient, and there is a need for the development of new personalized treatments to overcome the limitations of current mental health therapies. PEVs have various physiological functions, including mediating cellular communication in the central nervous system, which indicates associations among mental disorders. Therefore, we focused on the beneficial effects of PEVs on the brain and mental health. Recent research has shown that PEVs can adjust the expression of brain-derived neurotrophic factors in vitro and in vivo, demonstrating antidepressant and cognitive function improvement effects. This suggests that PEVs have potential as therapeutic agents for improving mental health and treating brain disorders. Based on this, we review these findings and present the beneficial effects of PEVs on mental health and the challenges that need to be addressed.

Probiotic nucleotides increase IL-10 expression in airway macrophages to mitigate airway allergy

BACKGROUND

Dysfunctional immune regulation plays a crucial role in the pathogenesis of airway allergies. Macrophages are one of the components of the immune regulation cells. The aim of this study is to elucidate the role of lysine demethylase 5 A (KDM5A) in maintaining macrophages' immune regulatory ability.

METHODS

DNA was extracted from Lactobacillus rhamnosus GG to be designated as LgDNA. LgDNA was administered to the mice through nasal instillations. M2 macrophages (M2 cells) were isolated from the airway tissues using flow cytometry.

RESULTS

We found that airway M2 cells of mice with airway Th2 polarization had reduced amounts of IL-10 and KDM5A. Mice with Kdm5a deficiency in M2 cells showed the airway Th2 polarization. The expression of Kdm5a in airway M2 cells was enhanced by nasal instillations containing LgDNA. KDM5A mediated the effects of LgDNA on inducing the Il10 expression in airway M2 cells. Administration of LgDNA mitigated experimental airway allergy.

CONCLUSIONS

M2 macrophages in the airway tissues of mice with airway allergy show low levels of KDM5A. By upregulating KDM5A expression, LgDNA can increase Il10 expression and reconcile airway Th2 polarization.

Oral co-administration of Lactiplantibacillus plantarum 16 and Lacticaseibacillus rhamnosus P118 improves host defense against influenza A virus infection

Influenza is an important zoonotic disease that persistently threatens global public health. While it is widely acknowledged that probiotics can modulate the host response to protect the host against infectious disease, the prophylactic efficacy on respiratory viral infection and the detailed mechanism remains elusive. Lactobacillus, the most commonly used probiotic widely applied in food production, has garnered significant attention. In our study utilizing both C57BL/6 and BALB/c mouse models, we explored the protective effect against two strains of influenza virus, A/Mink/China/01/2014(H9N2) and A/California/04/2009(H1N1), through the administration of Lactiplantibacillus plantarum strain 16 (L. plantarum 16) and Lacticaseibacillus rhamnosus strain P118 (L. rhamnosus P118), aiming to identify robust probiotic strains with antiviral properties. Our findings indicate that administering L. plantarum 16 or L. rhamnosus P118 alone does not provide sufficient protection against influenza. However, the co-administration of L. plantarum 16 and L. rhamnosus P118 dramatically reduces viral titers in the respiratory tract and lung, thereby markedly alleviating the clinical symptoms, improving prognosis, and reducing mortality. The mechanisms underlying this effect involve the modulation of host gut microbiota and metabolism through the co-administration of L. plantarum 16 and L. rhamnosus P118, resulting in enrichment of Firmicutes and enhancement of phenylalanine-related metabolism, ultimately leading to an augmentation of the antiviral immune response. Notably, we identified that the circulating metabolic molecule 2-Hydroxycinnamic acid plays a significant role in combating influenza. Our data suggest the potential utility of L. plantarum 16 and L. rhamnosus P118 two-bacterium or 2-Hydroxycinnamic acid in preventing influenza.IMPORTANCEVaccination represents the most optimal strategy to control influenza. Nevertheless, influenza viruses constantly evolve due to antigenic drift and shift, leading to the need for regular updates on influenza vaccines. Additionally, vaccination failure poses significant challenges to influenza prevention. Therefore, it is essential and beneficial to identify novel or universal antiviral measures to protect against influenza. While cumulative data suggest that probiotics offer protection against infectious diseases, the specific mechanisms, such as the effective metabolites or components, remain largely unknown. Our research discovered the capacity of combinational two-bacterium Lactiplantibacillus plantarum 16 and Lacticaseibacillus rhamnosus P118 to fight against influenza infection in a mouse model. The protection may occur through modulating the host's gut microbiota and metabolism, further influencing the host's antiviral immune response. Notably, we have identified a novel metabolic molecule, 2-Hydroxycinnamic acid, capable of enhancing antiviral response and restricting viral replication in vivo.

Intestinal Barrier Impairment, Preservation, and Repair: An Update

BACKGROUND/OBJECTIVES

Our objective was to review published studies of the intestinal barrier and permeability, the deleterious effects of dietary components (particularly fat), the impact of altered intestinal permeability in disease models and human diseases, the role of the microbiome and epigenomics in control of barrier function, and the opportunities to restore normal barrier function with dietary interventions and products of the microbiota.

METHODS

We conducted a literature review including the following keywords alone or in combination: intestinal barrier, permeability, microbiome, epigenomics, diet, irritable bowel syndrome, inflammatory bowel disease, probiotics.

RESULTS

Intestinal permeability is modified by a diet including fat, which increases permeability, and nutrients such as fiber, glutamine, zinc, vitamin D, polyphenols, emulsifiers, and anthocyanins, which decrease permeability. There is significant interaction of the microbiome and barrier function, including the inflammatory of luminal/bacterial antigens, and anti-inflammatory effects of commensals or probiotics and their products, including short-chain fatty acids. Epigenomic modification of barrier functions are best illustrated by effects on junction proteins or inflammation. Detailed documentation of the protective effects of diet, probiotics, prebiotics, and microbiota is provided.

CONCLUSION

intestinal permeability is a critical factor in protection against gastrointestinal diseases and is impacted by nutrients that preserve or heal and repair the barrier and nurture anti-inflammatory effects.

Chimeric Antigen-LgDNA Nanoparticles Attenuate Airway Th2 Polarization

Introduction

The therapeutic efficacy for airway allergies needs to be improved. Th2 polarization is a primary pathological feature of airway allergies. We constructed chimeric antigen-LgDNA (Lactobacillus rhamnosus DNA) nanoparticles (CAP-NPs). The effects of CAP-NPs on reconciling airway Th2 polarization were tested.

Methods

In this study, disulfide bond-linked antigen-major histocompatibility complex II (MHC II)-LgDNA nanoparticles (NPs) were constructed and designated CAP-NPs. An airway Th2 polarization mouse model was established to test the effects of CAP-NPs on suppressing the Th2 response.

Results

The CAP-NP components of ovalbumin (OVA), major histocompatibility complex II (MHC II), and LgDNA were confirmed in a series of laboratory tests. The CAP-NPs remained stable at pH7.2 for at least 96 h. In in vitro experiments, CAP-NPs bound to the surface of OVA-specific CD4+ T cells, which resulted in apoptosis of the antigen-specific CD4+ T cells. Removal of any of the three components from the NPs abolished the induction of apoptosis of antigen specific CD4+ T cells. CAP-NPs increased the expression of lysine-specific demethylase 5A (KDM5A) in CD4+ T cells. Histone H3K9 and the gene promoter of caspase 8 were demethylated by KDM5A, which led to transcription and expression of the caspase 8 gene. Administration of CAP-NPs significantly alleviated experimental airway Th2 polarization through activating the caspase 8-apoptosis signaling pathway.

Discussion

In this paper, we constructed CAP-NPs that could induce antigen-specific CD4+ T cell apoptosis. Administration of CAP-NPs efficiently alleviated experimental airway Th2 polarization.

Effects of inactivated Lactobacillus rhamnosus on growth performance, serum indicators, and colonic microbiota and metabolism of weaned piglets

BACKGROUND

To assess the effects of inactivated Lactobacillus rhamnosus (ILR) on growth performance, serum biochemical indices, colonic microbiota, and metabolomics in weaned piglets, 120 piglets were randomly divided into five groups. Samples in the control group were fed a basal diet, while the experimental ILR1, ILR2, ILR3, and ILR4 groups were fed basal diets supplemented with 0.1%, 0.2%, 0.3%, and 0.4% ILR, respectively. The prefeeding period lasted for 5 days and was followed by a formal period of 28 days.

RESULTS

Compared to the control, the average daily gain increased by 4.38%, 7.98%, 19.32%, and 18.80% for ILR1, ILR2, ILR3, and ILR4, respectively, and the ratio of feed to gain decreased by 0.63%, 3.80%, 12.66%, and 10.76%, respectively. Serum IgA, IgG, IgM, total antioxidant capacity, and glutathione peroxidase levels increased significantly in weaned piglets in the treatment groups. Addition of 0.3% ILR significantly increased the Shannon and Simpson indices of the colonic microbiota in weaned piglets and altered the microbiota composition. Changes in metabolic profiles were observed and were primarily related to the urea cycle, amino acid metabolism, and lipid metabolism.

CONCLUSION

ILR improved growth performance and serum immunological and biochemical indices and optimized the colonic microbiota structure and metabolism of weaned piglets.

Effect of gastrointestinal resistant encapsulate matrix on spray dried microencapsulated Lacticaseibacillus rhamnosus GG powder and its characterization

This study investigated spray drying a method for microencapsulating Lacticaseibacillus rhamnosus GG using a gastrointestinal resistant composite matrix. An encapsulate composite matrix comprising green banana flour (GBF) blended with maltodextrin (MD) and gum arabic (GA). The morphology of resulted microcapsules revealed a near-spherical shape with slight dents and no surface cracks. Encapsulation efficiency and product yield varied significantly among the spray-dried microencapsulated probiotic powder samples (SMPPs). The formulation with the highest GBF concentration (FIV) exhibited maximum post-drying L. rhamnosus GG viability (12.57 ± 0.03 CFU/g) and best survivability during simulated gastrointestinal digestion (9.37 ± 0.05 CFU/g). Additionally, glass transition temperature (Tg) analysis indicated good thermal stability of SMPPs (69.3 - 92.9 ℃), while Fourier Transform infrared (FTIR) spectroscopy confirmed the structural integrity of functional groups within microcapsules. The SMPPs characterization also revealed significant variation in moisture content, water activity, viscosity, and particle size. Moreover, SMPPs exhibited differences in total phenolic and flavonoid, along with antioxidant activity and color values throughout the study. These results suggested that increasing GBF concentration within the encapsulating matrix, while reducing the amount of other composite materials, may offer enhanced protection to L. rhamnosus GG during simulated gastrointestinal conditions, likely due to the gastrointestinal resistance properties of GBF.

Physiological and Technological Properties of Probiotic Lacticaseibacillus rhamnosus GG Encapsulated with Alginate-Chitosan Mixture and Its Incorporation in Whole Milk

This study developed and evaluated chitosan-sodium alginate capsules containing the probiotic Lacticaseibacillus rhamnosus GG using extrusion and emulsification techniques. The encapsulated L. rhamnosus GG cells were also evaluated for technological and probiotic-related physiological functionalities, as well as when incorporated in UHT and powdered milk. Extrusion (86.01 ± 1.26%) and emulsification (74.43 ± 1.41%) encapsulation techniques showed high encapsulation efficiency and high survival rates of L. rhamnosus GG during 28 days of refrigeration and room temperature storage, especially emulsification capsules (> 81%). The encapsulated L. rhamnosus GG cells showed high survival rates during exposure to simulated gastrointestinal conditions (72.65 ± 1.09-114.15 ± 0.44%). L. rhamnosus GG encapsulated by extrusion and emulsification performed satisfactorily in probiotic-related physiological (pH and bile salts tolerance) and technological properties (positive proteolytic activity, diacetyl and exopolysaccharides production, high NaCl tolerance (> 91%), besides having high heat tolerance (> 76%)). L. rhamnosus GG in extrusion and emulsification capsules had high survival rates (> 89%) and did not significantly affect physicochemical parameters in Ultra-High Temperature (UHT) and powdered milk during storage. The results demonstrate that L. rhamnosus GG can be successfully encapsulated with alginate-chitosan as a protective material through extrusion and emulsification techniques. UHT and powdered milk could serve as appropriate delivery systems to increase the intake of this encapsulated probiotic by consumers.

The Antidiabetic Potential of Probiotics: A Review

Diabetes has become one of the most prevalent global epidemics, significantly impacting both the economy and the health of individuals. Diabetes is associated with numerous complications, such as obesity; hyperglycemia; hypercholesterolemia; dyslipidemia; metabolic endotoxemia; intestinal barrier damage; insulin-secretion defects; increased oxidative stress; and low-grade, systemic, and chronic inflammation. Diabetes cannot be completely cured; therefore, current research has focused on developing various methods to control diabetes. A promising strategy is the use of probiotics for diabetes intervention. Probiotics are a class of live, non-toxic microorganisms that can colonize the human intestine and help improve the balance of intestinal microbiota. In this review, we summarize the current clinical studies on using probiotics to control diabetes in humans, along with mechanistic studies conducted in animal models. The primary mechanism by which probiotics regulate diabetes is improved intestinal barrier integrity, alleviated oxidative stress, enhanced immune response, increased short-chain fatty acid production, etc. Therefore, probiotic supplementation holds great potential for the prevention and management of diabetes.

Delphi Consensus Statement on the Role of Probiotics in the Treatment of Atopic Dermatitis

Background Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by intense itching and recurrent eczematous lesions. Important factors in the etiopathogenesis of AD include genetic predisposition, epidermal barrier dysfunction, immune dysregulation, and gut and skin dysbiosis. Probiotics could be a potential preventive strategy for allergies including AD through immune system modulation as well as enhancement of the epithelial barrier integrity. To further understand the role of probiotics in the management of AD, a Knowledge, Attitude, and Practices (KAP) survey was conducted. Materials and methods A steering committee comprising nine experts formulated consensus recommendations on the role of probiotics in the management of AD and associated flare-ups through the use of the Knowledge, Attitude, and Practices questionnaire while analyzing literature reviews and responses from a national panel consisting of 175 members. The evidence strength and quality were evaluated based on the Agency for Healthcare Research and Quality (AHRQ) criteria. The acceptance of expert opinions as recommendations was considered upon receiving an endorsement from ≥70% of the panelists, as indicated by a Likert scale. Results The national panel emphasized that the improvement in nutritional status, immunomodulatory properties, and beneficial effects on the gastrointestinal (GI) tract and skin support the use of probiotics in AD. The panel agreed that probiotics should be a part of the complementary therapy in the management of AD and associated flare-ups. Mostly, a probiotics supplementation duration of eight to 12 weeks is preferred by dermatologists. Probiotics, when used as an adjuvant therapy, may serve as a strategy to reduce steroid usage or maintenance therapy in high-risk cases with flares. Conclusion A Delphi-mediated KAP response provides a real-life approach to the use of probiotics in the management of AD. It suggests that probiotics could be useful as an adjuvant therapy in the management of AD and associated flare-ups when used along with traditional treatment.

Exploring the Regulatory Effect of LPJZ-658 on Copper Deficiency Combined with Sugar-Induced MASLD in Middle-Aged Mice Based on Multi-Omics Analysis

Globally, metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed nonalcoholic fatty liver disease (NAFLD), is one of the most common liver disorders and is strongly associated with copper deficiency. To explore the potential effects and mechanisms of Lactiplantibacillus plantarum LPJZ-658, copper deficiency combined with a high-sugar diet-induced MASLD mouse model was utilized in this study. We fed 40-week-old (middle-aged) male C57BL/6 mice a copper-deficient and high-sugar diet for 16 weeks (CuDS), with supplementary LPJZ-658 for the last 6 weeks (CuDS + LPJZ-658). In this study, we measured body weight, liver weight, and serum biochemical markers. Lipid accumulation, histology, lipidomics, and sphingolipid metabolism-related enzyme expression were investigated to analyze liver function. Untargeted metabolomics was used to analyze the serum and the composition and abundance of intestinal flora. In addition, the correlation between differential liver lipid profiles, serum metabolites, and gut flora at the genus level was measured. The results show that LPJZ-658 significantly improves abnormal liver function and hepatic steatosis. The lipidomics analyses and metabolic pathway analysis identified sphingolipid, retinol, and glycerophospholipid metabolism as the most relevant metabolic pathways that characterized liver lipid dysregulation in the CuDS group. Consistently, RT-qPCR analyses revealed that the enzymes catalyzing sphingolipid metabolism that were significantly upregulated in the CuDS group were downregulated by the LPJZ-658 treatment. In addition, the serum metabolomics results indicated that the linoleic acid, taurine and hypotaurine, and ascorbate and aldarate metabolism pathways were associated with CuDS-induced MASLD. Notably, we found that treatment with LPJZ-658 partially reversed the changes in the differential serum metabolites. Finally, LPJZ-658 effectively regulated intestinal flora abnormalities and was significantly correlated with differential hepatic lipid species and serum metabolites. In conclusion, we elucidated the function and potential mechanisms of LPJZ-658 in alleviating copper deficiency combined with sugar-induced middle-aged MASLD and hope this will provide possible treatment strategies for improving MASLD.

Black Goji Berry (Lycium ruthenicum) Juice Fermented with Lactobacillus rhamnosus GG Enhances Inhibitory Activity against Dipeptidyl Peptidase-IV and Key Steps of Lipid Digestion and Absorption

With the global increase in hyperglycemia and hyperlipidemia, there is an urgent need to explore dietary interventions targeting the inhibition of dipeptidyl peptidase-IV (DPP-IV) and lipid digestion and absorption. This study investigated how Lactobacillus rhamnosus GG (LGG) affects various aspects of black goji berry (BGB) (Lycium ruthenicum Murr.) juice, including changes in physicochemical and functional properties, as well as microbiological and sensory attributes. Throughout the fermentation process with 2.5-10% (w/v) BGB, significantly improved probiotic viability, lactic acid production, and decreased sugar content. While total flavonoids increase, anthocyanins decrease, with no discernible change in antioxidant activities. Metabolite profiling reveals elevated phenolic compounds post-fermentation. Regarding the inhibition of lipid digestion and absorption, fermented BGB exhibits improved bile acid binding, and disrupted cholesterol micellization by approximately threefold compared to non-fermented BGB, while also increasing pancreatic lipase inhibitory activity. Furthermore, a decrease in cholesterol uptake was observed in Caco-2 cells treated with fermented BGB (0.5 mg/mL), with a maximum reduction of 16.94%. Fermented BGB also shows more potent DPP-IV inhibition. Sensory attributes are significantly improved in fermented BGB samples. These findings highlight the potential of BGB as a bioactive resource and a promising non-dairy carrier for LGG, enhancing its anti-hyperglycemic and anti-hyperlipidemic properties.

Lactobacillus rhamnosus GG improves cognitive impairments in mice with sepsis

Background

Survivors of sepsis may encounter cognitive impairment following their recovery from critical condition. At present, there is no standardized treatment for addressing sepsis-associated encephalopathy. Lactobacillus rhamnosus GG (LGG) is a prevalent bacterium found in the gut microbiota and is an active component of probiotic supplements. LGG has demonstrated to be associated with cognitive improvement. This study explored whether LGG administration prior to and following induced sepsis could ameliorate cognitive deficits, and explored potential mechanisms.

Methods

Female C57BL/6 mice were randomly divided into three groups: sham surgery, cecal ligation and puncture (CLP), and CLP+LGG. Cognitive behavior was assessed longitudinally at 7-9d, 14-16d, and 21-23d after surgery using an open field test and novel object recognition test. The impact of LGG treatment on pathological changes, the expression level of brain-derived neurotrophic factor (BDNF), and the phosphorylation level of the TrkB receptor (p-TrkB) in the hippocampus of mice at two weeks post-CLP (16d) were evaluated using histological, immunofluorescence, immunohistochemistry, and western blot analyses.

Results

The CLP surgery induced and sustained cognitive impairment in mice with sepsis for a minimum of three weeks following the surgery. Compared to mice subjected to CLP alone, the administration of LGG improved the survival of mice with sepsis and notably enhanced their cognitive functioning. Moreover, LGG supplementation significantly alleviated the decrease in hippocampal BDNF expression and p-TrkB phosphorylation levels caused by sepsis, preserving neuronal survival and mitigating the pathological changes within the hippocampus of mice with sepsis. LGG supplementation mitigates sepsis-related cognitive impairment in mice and preserves BDNF expression and p-TrkB levels in the hippocampus.

Lactic Acid Bacteria-Derived Postbiotics as Adjunctive Agents in Breast Cancer Treatment to Boost the Antineoplastic Effect of a Conventional Therapeutic Comprising Tamoxifen and a New Drug Candidate: An Aziridine-Hydrazide Hydrazone Derivative

Breast cancer is associated with high mortality and morbidity rates. As about 20-30% of patients exhibiting ER-positive phenotype are resistant to hormonal treatment with the standard drug tamoxifen, finding new therapies is a necessity. Postbiotics, metabolites, and macromolecules isolated from probiotic bacteria cultures have been proven to have sufficient bioactivity to exert prohealth and anticancer effects, making them viable adjunctive agents for the treatment of various neoplasms, including breast cancer. In the current study, postbiotics derived from L. plantarum and L. rhamnosus cultures were assessed on an in vitro breast cancer model as potential adjunctive agents to therapy utilizing tamoxifen and a candidate aziridine-hydrazide hydrazone derivative drug. Cell viability and cell death processes, including apoptosis, were analyzed for neoplastic MCF-7 cells treated with postbiotics and synthetic compounds. Cell cycle progression and proliferation were analyzed by PI-based flow cytometry and Ki-67 immunostaining. Postbiotics decreased viability and triggered apoptosis in MCF-7, modestly affecting the cell cycle and showing a lack of negative impact on normal cell viability. Moreover, they enhanced the cytotoxic effect of tamoxifen and the new candidate drug toward MCF-7, accelerating apoptosis and the inhibition of proliferation. This illustrates postbiotics' potential as natural adjunctive agents supporting anticancer therapy based on synthetic drugs.

Lactobacillus rhamnosus GG Stimulates Dietary Tryptophan-Dependent Production of Barrier-Protecting Methylnicotinamide

BACKGROUND & AIMS

Lacticaseibacillus rhamnosus GG (LGG) is the world's most consumed probiotic but its mechanism of action on intestinal permeability and differentiation along with its interactions with an essential source of signaling metabolites, dietary tryptophan (trp), are unclear.

METHODS

Untargeted metabolomic and transcriptomic analyses were performed in LGG monocolonized germ-free mice fed trp-free or -sufficient diets. LGG-derived metabolites were profiled in vitro under anaerobic and aerobic conditions. Multiomic correlations using a newly developed algorithm discovered novel metabolites tightly linked to tight junction and cell differentiation genes whose abundances were regulated by LGG and dietary trp. Barrier-modulation by these metabolites were functionally tested in Caco2 cells, mouse enteroids, and dextran sulfate sodium experimental colitis. The contribution of these metabolites to barrier protection is delineated at specific tight junction proteins and enterocyte-promoting factors with gain and loss of function approaches.

RESULTS

LGG, strictly with dietary trp, promotes the enterocyte program and expression of tight junction genes, particularly Ocln. Functional evaluations of fecal and serum metabolites synergistically stimulated by LGG and trp revealed a novel vitamin B3 metabolism pathway, with methylnicotinamide (MNA) unexpectedly being the most robust barrier-protective metabolite in vitro and in vivo. Reduced serum MNA is significantly associated with increased disease activity in patients with inflammatory bowel disease. Exogenous MNA enhances gut barrier in homeostasis and robustly promotes colonic healing in dextran sulfate sodium colitis. MNA is sufficient to promote intestinal epithelial Ocln and RNF43, a master inhibitor of Wnt. Blocking trp or vitamin B3 absorption abolishes barrier recovery in vivo.

CONCLUSIONS

Our study uncovers a novel LGG-regulated dietary trp-dependent production of MNA that protects the gut barrier against colitis.

Molecular Mechanisms of Lacticaseibacillus rhamnosus, LGG® Probiotic Function

To advance probiotic research, a comprehensive understanding of bacterial interactions with human physiology at the molecular and cellular levels is fundamental. Lacticaseibacillus rhamnosus LGG® is a bacterial strain that has long been recognized for its beneficial effects on human health. Probiotic effector molecules derived from LGG®, including secreted proteins, surface-anchored proteins, polysaccharides, and lipoteichoic acids, which interact with host physiological processes have been identified. In vitro and animal studies have revealed that specific LGG® effector molecules stimulate epithelial cell survival, preserve intestinal barrier integrity, reduce oxidative stress, mitigate excessive mucosal inflammation, enhance IgA secretion, and provide long-term protection through epigenetic imprinting. Pili on the cell surface of LGG® promote adhesion to the intestinal mucosa and ensure close contact to host cells. Extracellular vesicles produced by LGG® recapitulate many of these effects through their cargo of effector molecules. Collectively, the effector molecules of LGG® exert a significant influence on both the gut mucosa and immune system, which promotes intestinal homeostasis and immune tolerance.

Recent progresses in gut microbiome mediates obstructive sleep apnea-induced cardiovascular diseases

Obstructive sleep apnea (OSA) is a multifactorial sleep disorder with a high prevalence in the general population. OSA is associated with an increased risk of developing cardiovascular diseases (CVDs), particularly hypertension, and is linked to worse outcomes. Although the correlation between OSA and CVDs is firmly established, the mechanisms are poorly understood. Continuous positive airway pressure is primary treatment for OSA reducing cardiovascular risk effectively, while is limited by inadequate compliance. Moreover, alternative treatments for cardiovascular complications in OSA are currently not available. Recently, there has been considerable attention on the significant correlation between gut microbiome and pathophysiological changes in OSA. Furthermore, gut microbiome has a significant impact on the cardiovascular complications that arise from OSA. Nevertheless, a detailed understanding of this association is lacking. This review examines recent advancements to clarify the link between the gut microbiome, OSA, and OSA-related CVDs, with a specific focus on hypertension, and also explores potential health advantages of adjuvant therapy that targets the gut microbiome in OSA.

Metabolomic and Transcriptomic Correlative Analyses in Germ-Free Mice Link Lacticaseibacillus rhamnosus GG-Associated Metabolites to Host Intestinal Fatty Acid Metabolism and β-Oxidation

Intestinal microbiota confers susceptibility to diet-induced obesity, yet many probiotic species that synthesize tryptophan (trp) actually attenuate this effect, although the underlying mechanisms are unclear. We monocolonized germ-free mice with a widely consumed probiotic Lacticaseibacillus rhamnosus GG (LGG) under trp-free or -sufficient dietary conditions. We obtained untargeted metabolomics from the mouse feces and serum using liquid chromatography-mass spectrometry and obtained intestinal transcriptomic profiles via bulk-RNA sequencing. When comparing LGG-monocolonized mice with germ-free mice, we found a synergy between LGG and dietary trp in markedly promoting the transcriptome of fatty acid metabolism and β-oxidation. Upregulation was specific and was not observed in transcriptomes of trp-fed conventional mice and mice monocolonized with Ruminococcus gnavus. Metabolomics showed that fecal and serum metabolites were also modified by LGG-host-trp interaction. We developed an R-Script-based MEtabolome-TRanscriptome Correlation Analysis algorithm and uncovered LGG- and trp-dependent metabolites that were positively or negatively correlated with fatty acid metabolism and β-oxidation gene networks. This high-throughput metabolome-transcriptome correlation strategy can be used in similar investigations to reveal potential interactions between specific metabolites and functional or disease-related transcriptomic networks.

Characterization of an exopolysaccharide synthesized by Lacticaseibacillus rhamnosus B6 and its immunomodulatory activity in vitro

An exopolysaccharide, designated F1, was purified from the fermented milk by Lacticaseibacillus rhamnosus strain B6 (CGMCC No. 13310). F1, with the weight average molecular weight of 1.577 × 106 Da, is consisted of rhamnose, glucose and galactose in a molar ratio of 3.7:1.5: 1. The backbone included 1,3-linked Rha, 1,2,3-linked Rha, 1,2-linked Glc and 1,3-linked Glc residues, with the branching point located at O2 position of 1,2,3-linked Rha residue, and the branch chain composed of terminal linked galactose residue with a pyruvate substituent. F1 could significantly stimulate the phagocytic activity and TNF-α expression in RAW 264.7 macrophages in a dose-dependent manner, and the release of NO at 200 μg/mL as well. F1 at 200 μg/mL could stimulate the expression of the pro-inflammatory cytokine encoding genes including TNF-α and iNOS, but with a negligible upregulating effect on the mRNA expression of IL-10. F1 could up-regulate the expression of NF-κBp65 and skew macrophage polarization towards M1 phenotype. These results suggest F1 elicit an immunomodulatory effect through the NF-κB signaling pathway.

In vitro and in vivo genome-based safety evaluation of Lacticaseibacillus rhamnosus LRa05

The aim of this study was to comprehensively evaluate the safety of Lacticaseibacillus rhamnosus LRa05 (hereinafter "LRa05") to determine its suitability for use as a probiotic in the food industry. First, we sequenced the genome of LRa05 and then determined whether it contained genes associated with antibiotic resistance, virulence, or pathogenicity. Second, we evaluated the safety of LRa05 in vitro by performing a hemolysis assay and examining its ability to produce biogenic amines, its antimicrobial susceptibility, its capacity to transfer antibiotic resistance genes, its genomic stability, and whether it contained potential virulence factors. Third, we investigated the pathogenicity of LRa05 in mice by oral gavage and intraperitoneal injection. A bioinformatics analysis revealed no evidence that the genome of LRa05 contains genes associated with virulence or antibiotic resistance. In addition, the results of in vitro experiments showed that LRa05 does not produce d-lactic acid or exhibit hemolytic activity and is sensitive to clinically relevant antibiotics. Furthermore, a pathogenicity test revealed that LRa05 exhibits no lethality or toxicity in mice. Taken together, these findings indicate that LRa05 is sufficiently safe to be explored as a potential probiotic for use in the food industry.