Probiotic Lactobacillus rhamnosus modulates MCLR-induced oogenesis disorders in zebrafish: Evidence from the transcriptome.

Microcystin-LR (MCLR) produced by cyanobacterial blooms have received global attention. MCLR has been recognized as a reproductive toxin to fish and poses a threat to ecosystem stability. It has been proven that probiotic dietary management can improve reproductive performance of fish. It is worth paying attention to exploring whether probiotic management can alleviate the reproductive toxicity caused by MCLR. In this investigation, adult zebrafish were exposed to different doses of MCLR solution (0, 2.2, and 22 µg/L) with or without the Lactobacillus rhamnosus GG supplementation for a duration of 28 days. The results showed that female zebrafish spawning was reduced after exposure to MCLR, but this reduction was reversed when L. rhamnosus GG was added. To elucidate how L. rhamnosus GG mitigates reproductive toxicity caused by MCLR, we examined a series of indicators of MCLR accumulation, ovarian histology, hormones, and transcriptome levels. Our study showed that L. rhamnosus GG could alleviate oogenesis disorders and ultimately attenuate MCLR-induced reproductive toxicity by reducing MCLR accumulation in the gonads, modulating the expression of endocrine system and auto/paracrine factors. The transcriptome results revealed that single or combined exposure of MCLR and L. rhamnosus GG mainly affected the endocrine system, energy metabolism, and RNA degradation and translation. Overall, our results provide new insights for alleviating MCLR-induced reproductive toxicity and help promote healthy aquaculture.

Lacticaseibacillus rhamnosus GG alleviates sleep deprivation-induced intestinal barrier dysfunction and neuroinflammation in mice.

Consuming probiotic products is a solution that people are willing to choose to augment health. As a global health hazard, sleep deprivation (SD) can cause both physical and mental diseases. The present study investigated the protective effects of Lacticaseibacillus rhamnosus GG (LGG), a widely used probiotic, on a SD mouse model. Here, it has been shown that SD induced intestinal damage in mice, while LGG supplementation attenuated disruption of the intestinal barrier and enhanced the antioxidant capacity. Microbiome analysis revealed that SD caused dysbiosis in the gut microbiota, characterized by increased levels of Clostridium XlVa, Alistipes, and Desulfovibrio, as well as decreased levels of Ruminococcus, which were partially ameliorated by LGG. Moreover, SD resulted in elevated pro-inflammatory cytokine concentrations in both the intestine and the brain, while LGG provided protection in both organs. LGG supplementation significantly improved locomotor activity in SD mice. Although heat-killed LGG showed some protective effects in SD mice, its overall efficacy was inferior to that of live LGG. In terms of mechanism, it was found that AG1478, an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, could diminish the protective effects of LGG. In conclusion, LGG demonstrated the ability to alleviate SD-induced intestinal barrier dysfunction through EGFR activation and alleviate neuroinflammation.

Anti-Persisters Activity of Lacticaseibacillus rhamnosus Culture Filtrates against Pseudomonas aeruginosa in Artificial Sputum Medium.

Persisters are antibiotic-tolerant bacteria, playing a role in the recalcitrance and relapse of many bacterial infections, including P. aeruginosa pulmonary infections in Cystic Fibrosis (CF) patients. Among novel antimicrobial strategies, the use of probiotics and their products is emerging as a particularly promising approach. The aim of this study was to evaluate the anti-persisters activity of culture filtrate supernatants of Lacticaseibacillus rhamnosus (LRM-CFS) against P. aeruginosa in artificial sputum medium (ASM), which resembles the CF lung environment. Planktonic persisters of two clinical strains of P. aeruginosa (PaCF1 and PaCF4) were obtained following two different procedures: (i) exposing stationary-phase cultures to cyanide m-chlorophenylhydrazone (CCCP) in LB medium; (ii) incubating stationary-phase cultures with high doses of tobramycin (128-fold MIC) in ASM. In addition, persisters from biofilm were obtained by exposing 48 h old biofilm of P. aeruginosa to 128 x MIC of ciprofloxacin. LRM-CFS at dilutions of 1:6 and 1:4 resulted in being bactericidal in ASM against both PaCF1 and PaCF4 persisters obtained after CCCP or tobramycin treatment. Moreover, LRM-CFS at dilution 1:4 caused a reduction of antibiotic-tolerant bacteria in the biofilm of both P. aeruginosa strains. Overall, LRM-CFS represents a promising adjuvant therapeutic strategy against P. aeruginosa recalcitrant infections in CF patients.

A neurotherapeutic approach with Lacticaseibacillus rhamnosus E9 on gut microbiota and intestinal barrier in MPTP-induced mouse model of Parkinson's disease.

The gut microbiota plays a crucial role in neural development and progression of neural disorders like Parkinson's disease (PD). Probiotics have been suggested to impact neurodegenerative diseases via gut-brain axis. This study aims to investigate the therapeutic potential of Lacticaseibacillus rhamnosus E9, a high exopolysaccharide producer, on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced mouse model of PD. C57BL/6 mice subjected to MPTP were fed L. rhamnosus E9 for fifteen days and sacrificed after the last administration. Motor functions were determined by open-field, catalepsy, and wire-hanging tests. The ileum and the brain tissues were collected for ELISA, qPCR, and immunohistochemistry analyses. The cecum content was obtained for microbiota analysis. E9 supplementation alleviated MPTP-induced motor dysfunctions accompanied by decreased levels of striatal TH and dopamine. E9 also reduced the level of ROS in the striatum and decreased the DAT expression while increasing the DR1. Furthermore, E9 improved intestinal integrity by enhancing ZO-1 and Occludin levels and reversed the dysbiosis of the gut microbiota induced by MPTP. In conclusion, E9 supplementation improved the MPTP-induced motor deficits and neural damage as well as intestinal barrier by modulating the gut microbiota in PD mice. These findings suggest that E9 supplementation holds therapeutic potential in managing PD through the gut-brain axis.

Exploring the potential of Lactocaseibacillus rhamnosus PMC203 in inducing autophagy to reduce the burden of Mycobacterium tuberculosis.

Mycobacterium tuberculosis, a lethal pathogen in human history, causes millions of deaths annually, which demands the development of new concepts of drugs. Considering this fact, earlier research has explored the anti-tuberculosis potential of a probiotic strain, Lactocaseibacillus rhamnosus PMC203, leading to a subsequent focus on the molecular mechanism involved in its effect, particularly on autophagy. In this current study, immunoblotting-based assay exhibited a remarkable expression of autophagy marker LC3-II in the PMC203 treated group compared to an untreated group. A remarkable degradation of p62 was also noticed within treated cells compared to control. Furthermore, the immunofluorescence-based assay showed significant fold change in fluorescence intensity for alexa-647-LC3 and alexa-488-LC3, whereas p62 was degraded noticeably. Moreover, lysosomal biogenesis generation was elevated significantly in terms of LAMP1 and acidic vesicular organelles. As a result, PMC203-induced autophagy played a vital role in reducing M. tuberculosis burden within the macrophages in treated groups compared to untreated group. A colony -forming unit assay also revealed a significant reduction in M. tuberculosis in the treated cells over time. Additionally, the candidate strain significantly upregulated the expression of autophagy induction and lysosomal biogenesis genes. Together, these results could enrich our current knowledge of probiotics-mediated autophagy in tuberculosis and suggest its implications for innovatively managing tuberculosis.

Effect of Lactobacillus gasseri BIO6369 and Lacticaseibacillus rhamnosus BIO5326 on Gastric Carcinogenesis Induced by Helicobacter pylori Infection.

BACKGROUND: Helicobacter pylori infection-associated gastric adenocarcinoma is influenced by various factors, including the digestive microbiota. Lactic acid bacteria role in digestive carcinogenesis has been discussed, and some Lactobacillaceae family species have been shown to act against H. pylori-induced inflammation and colonization. However, their effects on H. pylori-related carcinogenesis have not yet been studied. Lactobacillaceae family effects on the epithelial-to-mesenchymal transition (EMT), emergence of cells with cancer stem cell (CSC) properties and the pro-inflammatory response of gastric epithelial cells to H. pylori infection were investigated. MATERIALS AND METHODS: A co-culture model of AGS gastric epithelial cells infected with a carcinogenic strain of H. pylori associated with 18 different probiotic strains candidates were used. Different EMT indicators and CSC properties were studied, including quantification of the mesenchymal phenotype, tumorsphere formation, EMT marker expression, and tight junction evaluation with immunofluorescence microscopy. The effect of the strains on the pro-inflammatory response to H. pylori was also evaluated by quantifying interleukin-8 (IL-8) production using ELISA. RESULTS: Among the strains tested, Lactobacillus gasseri BIO6369 and Lacticaseibacillus rhamnosus BIO5326 induced a 30.6% and 38.4% reduction in the mesenchymal phenotype, respectively, caused a significant decrease in Snail and Zeb1 EMT marker expression and prevented the loss of tight junctions induced by H. pylori infection. A separate co-culture with a Boyden chamber maintained the effects induced by the two strains. H. pylori-induced IL-8 production was also significantly reduced in the presence of L. gasseri BIO6369 and L. rhamnosus BIO5326. CONCLUSION: Lactobacillus gasseri BIO6369 and L. rhamnosus BIO5326 strains decreased epithelial-to-mesenchymal transition and inflammation induced by H. pylori infection, suggesting that these species may have a protective effect against H. pylori-induced gastric carcinogenesis.

Lactobacillus rhamnosus GG and Tannic Acid Synergistically Promote the Gut Barrier Integrity in a Rat Model of Experimental Diarrhea via Selective Immunomodulatory Cytokine Targeting.

SCOPE: Diarrhea is a common health issue that contributes to a significant annual death rate among children and the elderly worldwide. The anti-diarrheal activity of Lactobacillus rhamnosus GG (LGG) and tannic acid (TA), alone or combined, is examined, in addition to their effect on intestinal barrier integrity. METHODS AND RESULTS: Fifty-six adult male Wistar rats are randomly assigned into seven groups: control, LGG alone, TA alone, diarrhea model, diarrhea+LGG, diarrhea+TA, and diarrhea+LGG+TA-treated groups. Diarrhea is induced by high-lactose diet (HLD) consumption. LGG (1x109 CFU/rat) and TA (100 mg Kg-1 d-1) were given orally 4 days after HLD feeding and continued for 10 days. Ileum specimens are processed for biochemical analysis of the local intestinal cytokines, polymerase chain reaction (PCR), and histological study. Also, immunohistochemistry-based identification of Proliferating Cell Nuclear Antigen (PCNA) and zonula occludens 1 (ZO-1) is performed. Compared to the diarrhea model group, both treatments maintain the intestinal mucosal structure and proliferative activity and preserve ZO-1 expression, with the combination group showing the maximal effect. However, LGG-treated diarrheic rats show a remarkable decrease in the intestinal tissue concentrations of tumor necrosis factor-alpha (TNF-α) and nuclear factor Kappa beta (NF-κB); meanwhile, TA treatment leads to a selective decrease of interferon-gamma (INF-γ) and transforming growth factor-beta (TGF-ß1). CONCLUSION: Individual LGG and TA treatments significantly alleviate diarrhea, probably through a selective immunomodulatory cytokine-dependent mechanism, while the combination of both synergistically maintains the intestinal mucosa by keeping the intestinal epithelial barrier function and regenerative capability.

Lacticaseibacillus rhamnosus LRa05 alleviated liver injury in mice with alcoholic fatty liver disease by improving intestinal permeability and balancing gut microbiota.

This study investigated the effect of Lacticaseibacillus rhamnosus LRa05 on alcoholic fatty liver disease (ALD) and its mechanism for liver protection. Mice were randomly divided into three groups: a control (CLT) group, an ALD group, and a LRa05 intervention group. The ALD mouse model was established by Lieber-DeCarli chronic alcohol feeding. Tissues staining, enzyme-linked immunosorbent assay (ELISA) was performed to detect changes in histopathology and inflammatory cytokines, respectively. Moreover, intestinal permeability was evaluated by the level of dextran-fluorescein isothiocyanate (Dx-FITC) in serum and tight junction protein in the colon. Changes in the composition of the gut microbiota were assessed by 16S rRNA sequencing. Alcohol consumption induced liver damage in mice with significantly increased levels of triglycerides (TG), aspartate aminotransferase (AST), alanine transaminase (ALT), and inflammatory cytokines. Moreover, alcohol further induced the increase of intestinal permeability and disruption of gut microbiota in mice, with an increase in the relative abundance of potentially pathogenic bacteria Enterococcus, Parabacteroides, and Alistipes. LRa05 intervention significantly attenuated alcohol-induced liver injury by reducing the contents of TG, ALT, and AST, and suppressing the inflammatory responses. Meanwhile, by stimulating the expression of ZO-1, Occludin, and Claudin in the colon tissue, LRa05 additionally strengthened the intestine barrier function. Furthermore, gut microbiota analysis suggested that LRa05 partially ameliorated gut microbiota disorders in ALD mice and up-regulated the abundance of Desulfovibrio and Akkermansia, which were negatively correlated with the indicators of ALD progression. The reconstructive effects of LRa05 on the gut microbiota might be related to the efficacy of LRa05 in improving gut permeability and further protecting against ALD.

The inhibition mechanism of co-cultured probiotics on biofilm formation of Klebsiella pneumoniae.

AIMS: Klebsiella pneumoniae, an important opportunistic pathogen of nosocomial inflection, is known for its ability to form biofilm. The purpose of the current study is to assess how co- or mono-cultured probiotics affect K. pneumoniae's ability to produce biofilms and investigate the potential mechanisms by using a polyester nonwoven chemostat and a Caco-2 cell line. METHODS AND RESULTS: Compared with pure cultures of Lactobacillus rhamnosus and Lactobacillus sake, the formation of K. pneumoniae biofilm was remarkably inhibited by the mixture of L. rhamnosus, L. sake, and Bacillus subtilis at a ratio of 5:5:1 by means of qPCR and FISH assays. In addition, Lactobacillus in combination with B. subtilis could considerably reduce the adherence of K. pneumoniae to Caco-2 cells by using inhibition, competition, and displacement assays. According to the RT-PCR assay, the adsorption of K. pneumoniae to Caco-2 cells was effectively inhibited by the co-cultured probiotics, leading to significant reduction in the expression of proinflammatory cytokines induced by K. pneumoniae. Furthermore, the HPLC and RT-PCR analyses showed that the co-cultured probiotics were able to successfully prevent the expression of the biofilm-related genes of K. pneumoniae by secreting plenty of organic acids as well as the second signal molecule (c-di-GMP), resulting in inhibition on biofilm formation. CONCLUSION: Co-culture of L. sake, L. rhamnosus, and B. subtilis at a ratio of 5:5:1 could exert an antagonistic effect on the colonization of pathogenic K. pneumoniae by down-regulating the expression of biofilm-related genes. At the same time, the co-cultured probiotics could effectively inhibit the adhesion of K. pneumoniae to Caco-2 cells and block the expression of proinflammatory cytokines induced by K. pneumoniae.

Effect of Postbiotics Derived from Lactobacillus rhamnosus PB01 (DSM 14870) on Sperm Quality: A Prospective In Vitro Study.

Vaginally administered postbiotics derived from Lactobacillus were recently demonstrated to be effective in alleviating bacterial vaginosis and increasing pregnancy rates. However, their potential effect on sperm quality has not been well investigated. This controlled in vitro study aimed to assess the dose- and time-dependent effects of postbiotics derived from Lactobacillus rhamnosus PB01 (DSM 14870) on sperm quality parameters. The experiment was conducted in vitro to eliminate potential confounding factors from the female reproductive tract and vaginal microbiota. Sperm samples from 18 healthy donors were subjected to analysis using Computer-Aided Sperm Analysis (CASA) in various concentrations of postbiotics and control mediums at baseline, 60 min, and 90 min of incubation. Results indicated that lower postbiotic concentration (PB5) did not adversely affect sperm motility, kinematic parameters, sperm DNA fragmentation, and normal morphology at any time. However, concentrations exceeding 15% demonstrated a reduction in progressively motile sperm and a negative correlation with non-progressively motile sperm at all time points. These findings underscore the importance of balancing postbiotic dosage to preserve sperm motility while realizing the postbiotics' vaginal health benefits. Further research is warranted to understand the underlying mechanisms and refine practical applications in reproductive health.

Lactobacilli decrease the susceptibility of Salmonella Typhimurium to azithromycin.

Bacteria are involved in numerous interactions during infection and among host-associated microbial populations. Salmonella enterica serovar Typhimurium is a foodborne pathogen of great importance as well as a model organism to study interactions within a microbial community. In this study, we found that S. Typhimurium becomes tolerant to azithromycin when co-cultured with lactobacilli strains. Similarly, acidified media, from cell-free supernatant of lactobacilli cultures for instance, also induced the tolerance of S. Typhimurium to azithromycin. The addition of membrane disruptors restored the normal sensitivity to azithromycin in acidified media, but not when lactobacilli were present. These results suggested that the acidification of the media led to modification in envelope homeostasis, but that a different mechanism promoted the tolerance to azithromycin in the presence of lactobacilli strains. To further understand how lactobacilli strains modify the sensitivity of S. Typhimurium to azithromycin, a high-throughput assay was performed using the single-gene deletion collection of the S. Typhimurium (1) in co-culture with Lacticaseibacillus rhamnosus and (2) in sterile acidic conditions (pH 5.5 media only). As expected, both screens identified genes involved in envelope homeostasis and membrane permeability. Our results also suggest that changes in the metabolism of S. Typhimurium induce the tolerance observed in the presence of L. rhamnosus. Our results thus highlight two different mechanisms by which lactobacilli induce the tolerance of S. Typhimurium to azithromycin.IMPORTANCEThis study provides valuable insights into the intricate interactions between bacteria during infections and within host-associated microbial communities. Specifically, it sheds light on the significant role of lactobacilli in inducing antibiotic tolerance in Salmonella enterica serovar Typhimurium, a critical foodborne pathogen and model organism for microbial community studies. The findings not only uncover the mechanisms underlying this antibiotic tolerance but also reveal two distinct pathways through which strains of lactobacilli might influence Salmonella's response to antibiotics. Understanding these mechanisms has the potential to enhance our knowledge of bacterial infections and may have implications for the development of strategies to combat antibiotic resistance in pathogens, such as Salmonella. Furthermore, our results underscore the necessity to explore beyond the direct antimicrobial effects of antibiotics, emphasizing the broader microbial community context.

How xylitol, gluten, and lactose change human gut microbiota Escherichia coli and Lactobacillus rhamnosus GG biofilm.

OBJECTIVE: The human gut microbiota is composed of many viruses, bacteria, and fungi. Escherichia coli representatives are facultative anaerobic bacteria in the colon that play a crucial role in the metabolism of lactose, vitamin synthesis, and immune system modulation. E. coli forms a biofilm on the epithelial cell surface of the intestine that can be modified by diet compounds, i.e., gluten, xylitol, lactose, and probiotics. METHODS: In the present study, the impact of probiotic-derived Lactobacillus rhamnosus GG strain on non-pathogenic E. coli biofilm was examined. The mono- and multispecies biofilm was also treated with gluten, xylitol, and lactose. We used 96-well plates to obtain biofilm growth. Biofilm was stained using crystal violet. To evaluate the type of interaction in mono- and multispecies biofilm, a new formula was introduced: biofilm interaction ratio index (BIRI). To describe the impact of nutrients on biofilm formation, the biofilm formation impact ratio (BFIR) was calculated. RESULTS: The biofilms formed by both examined species are stronger than in monocultures. All the BIRI values were above 3.0. It was found that the monospecies biofilm of L. rhamnosus is strongly inhibited by gluten (84.5%) and the monospecies biofilm of E. coli by xylitol (85.5%). The mixed biofilm is inhibited by lactose (78.8%) and gluten (90.6%). CONCLUSION: The relations between bacteria in the mixed biofilm led to changes in biofilm formation by E. coli and L. rhamnosus GG. Probiotics might be helpful in rebuilding the gut microbiota after broad spectrum antibiotic therapy, but only if gluten and lactose are excluded from diet.

Screening of probiotic strains to improve visceral hypersensitivity in irritable bowel syndrome by using in vitro and in vivo approaches.

Oral administration of probiotics has been proposed as a promising biotherapy to prevent and treat different diseases related to gastrointestinal disorders, such as irritable bowel syndrome (IBS). Due to the increasing research area on the characterisation of new probiotic bacterial strains, it is necessary to perform suitable in vitro experiments, using pertinent cellular models, in order to establish appropriate readout profiles based on IBS symptoms and subtypes. In this work, a collection of 30 candidate strains, belonging mainly to the Lactobacillus and Bifidobacterium genera, were screened using three different sets of in vitro experiments with different readouts to identify promising probiotic strains with: (1) the ability to inhibit the synthesis of IL-8 production by TNF-α stimulated HT-29 cells, (2) immunomodulatory properties quantified as increased IL-10 levels in peripheral blood mononuclear cell (PBMCs), and (3) the ability to maintain epithelial barrier integrity by increasing the trans-epithelial/endothelial electrical resistance (TEER) values in Caco-2 cells. Based on these criteria, three strains were selected: Lactobacillus gasseri PI41, Lacticaseibacillus rhamnosus PI48 and Bifidobacterium animalis subsp. lactis PI50, and tested in a murine model of low-grade inflammation induced by dinitrobenzene sulfonic acid (DNBS), which mimics some of the symptoms of IBS. Among the three strains, L. gasseri PI41 improved overall host well-being by preventing body weight loss in DNBS-treated mice and restored gut homeostasis by normalising the intestinal permeability and reducing pro-inflammatory markers. Therefore, the potential of this strain was confirmed in a second murine model known to reproduce IBS symptoms: the neonatal maternal separation (NMS) model. The PI41 strain was effective in preventing intestinal permeability and reducing colonic hypersensitivity. In conclusion, the set of in vitro experiments combined with in vivo assessments allowed us to identify a promising probiotic candidate strain, L. gasseri PI41, in the context of IBS.

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.

In ovo probiotic supplementation supports hatchability and improves hatchling quality in broilers.

In modern broilers, the period of embryonic development constitutes a greater proportion of a broiler's productive life. Hence, optimum embryonic development can exert a significant influence not only on chick hatchability and hatchling quality but also on overall broiler growth and performance. Further healthy and active hatchlings are correlated with improved posthatch performance. In this regard, probiotics are good candidates to mediate early-life programming. Therefore, we evaluated the effect of In ovo probiotic spray application on broiler hatchability and hatchling quality. The experiment was set out as a completely randomized study with 2 independent trials. In each trial, 540 eggs (Ross 308) were either sprayed with phosphate buffered saline (PBS; control) or probiotics [∼9 log CFU/egg of Lactobacillus rhamnosus NRRL B-442(LR) or Lactobacillus paracasei DUP 13076 (LP)] during incubation. On day 18, eggs were transferred to the hatcher and set up for hatching. Starting on day 19, eggs were observed for hatching to determine the spread of hatch and hatchability. Hatched chicks were then assessed for quality using the Tona and Pasgar score and morphometric measurements including hatchling weight, yolk-free-body-mass and hatchling length were measured. Further, chicks were reared in floor pens for 3 wk to assess posthatch growth. Overall, In ovo probiotic supplementation improved hatchability and hatchling quality. Specifically, the spray application of LP improved hatchability by ∼ 5% without affecting the spread of hatch. Further, both LR and LP significantly improved Pasgar and Tona score, indicating an improvement in hatchling quality. Also, LP and LR significantly improved hatchling weight, yolk-free-body-mass, and posthatch growth in chicks. LR significantly improved hatchling weight and hatchling length (P < 0.05). Moreover, this increase in posthatch growth was positively correlated with hatchling weight in the probiotic groups. Overall, our study demonstrates that In ovo probiotic application exerts a positive effect on hatchability, hatchling quality, and subsequent posthatch growth.

Multi-strain probiotic improves subjective sleep quality with no impact on body composition, hemodynamics, and physical activity.

The objective of the study was to examine the impact of a multi-strain probiotic (MSP) on sleep, physical activity, and body composition changes. We used a randomised, double-blind, placebo-controlled approach with 70 healthy men and women (31.0 ± 9.5 years, 173.0 ± 10.4 cm, 73.9 ± 13.8 kg, 24.6 ± 3.5 kg/m2) supplemented daily with MSP (4 × 109 live cells Limosilactobacillus fermentum LF16, Lacticaseibacillus rhamnosus LR06, Lactiplantibacillus plantarum LP01, and Bifidobacterium longum 04; Probiotical S.p.A., Novara, Italy) or placebo (PLA). In response to supplementation (after 0, 2, 4, and 6 weeks of supplementation) and 3 weeks after stopping supplementation, participants had subjective (Pittsburgh Sleep Quality Index, PSQI) and objective sleep indicators, body composition, daily physical activity and resting hemodynamics assessed. Subjective sleep quality indicators using the PSQI (sleep latency, sleep disturbance, and global PSQI score) improved ( P < 0.05) at various time points with MSP supplementation. Systolic blood pressure in PLA increased ( P < 0.05) after 6 weeks of supplementation with no change in MSP. No changes ( P > 0.05) in sleep (hours asleep, minutes awake, number of times awake) or physical activity (step count, minutes of sedentary activity, total active minutes) metrics assessed by the wearable device were observed. Additionally, no changes in resting heart rate, diastolic blood pressure, and body composition were discerned. In conclusion, MSP supplementation improved the subjective ability to fall asleep faster and disturbances experienced during sleep, which resulted in improved overall sleep quality as assessed by the PSQI. No differences in other sleep indicators, physical activity, hemodynamics, and body composition were observed during or following MSP supplementation. Registered at clinicaltrials.gov: NCT05343533.

The effect of Lactobacillus rhamnosus B10 on alcoholic liver injury and intestinal microbiota in alcohol-induced mice model.

Lactobacillus rhamnosus B10 (L. rhamnosus B10) isolated from the baby feces was given to an alcohol mice model, aiming to investigate the effects of L. rhamnosus B10 on alcoholic liver injury by regulating intestinal microbiota. C57BL/6N mice were fed with liquid diet Lieber-DeCarli with or without 5% (v/v) ethanol for 8 weeks, and treated with L. rhamnosus B10 at the last 2 weeks. The results showed that L. rhamnosus B10 decreased the serum total cholesterol (1.48 mmol/L), triglycerides (0.97 mmol/L), alanine aminotransferase (26.4 U/L), aspartate aminotransferase (14.2 U/L), lipopolysaccharide (0.23 EU/mL), and tumor necrosis factor-α (138 pg/mL). In addition, L. rhamnosus B10 also reduced the liver triglycerides (1.02 mmol/g prot), alanine aminotransferase (17.8 mmol/g prot) and aspartate aminotransferase (12.5 mmol/g prot) in alcohol mice, thereby ameliorating alcohol-induced liver injury. The changes of intestinal microbiota composition on class, family and genus level in cecum were analyzed. The intestinal symbiotic abundance of Firmicutes was elevated while gram-negative bacteria Proteobacteria and Deferribacteres was decreased in alcohol mice treated with L. rhamnosus B10 for 2 weeks. In summary, this study provided evidence for the therapeutic effects of probiotics on alcoholic liver injury by regulating intestinal flora.

A randomized trial of probiotic supplementation in nurses to reduce stress and viral illness.

Animal studies demonstrate how the gut microbiota influence psychological health and immunity to viral infections through their actions along multiple dynamic pathways in the body. Considerable interest exists in probiotics to reduce stress and illness symptoms through beneficial effects in the gut, but translating pre-clinical evidence from animal models into humans remains challenging. We conducted a large trial in nurses working during the 2020 COVID19 pandemic year to establish whether daily ingestion of the probiotic Lactobacillus rhamnosus HN001 reduced perceived stress and the number of days participants reported symptoms of a viral illness. Our results showed no significant difference in perceived stress or the average number of illness days between probiotic supplemented nurses and the placebo group. Stress and viral illness symptoms reduced during the study for all participants, a trajectory likely influenced by societal-level factors. The powerful effect of a well-managed public health response to the COVID19 pandemic and the elimination of COVID19 from the community in 2020 may have altered the trajectory of stress levels and reduced circulating viral infections making it difficult to detect any effect of probiotic supplementation. Our study highlights the challenge in controlling environmental factors in human trials.

The effects of ultraviolet, gamma- and X-ray irradiation on the growth, antibacterial activity and radio-protective of Lactobacillus rhamnosus.

Ionizing radiation is widely applied in food production as preservation technology and for correction of the gut microbiome of cancer patients, rescuers, astronauts etc. Lactic acid bacteria (LAB) can be used for the same reason. The main goal of this study was to investigate the effect of irradiation on some activities of Lactobacillus rhamnosus MDC 9661 and its effect on the survival of irradiated rats. The results indicate that both ultraviolet (during 45 min) and X-ray irradiations (with 2 Sv) decreased the CFU and the antibacterial activity of the strain. Higher than 700 Sv dose of X-ray irradiation resulted in the total inhibition of antibacterial activity with the total reduction of colony forming units less than 10 cells ml-1 , while irradiated with 1000 Sv dose L. rhamnosus MDC 9661 did not lose its proteolytic activity. It was also shown that L. rhamnosus MDC 9661 was not immunogenic in the organism of the rats and cannot lead to the development of autoimmune responses. L. rhamnosus MDC 9661 demonstrated the necessary properties for probiotics and can be effectively used for the correction of the gut microbiome of all target groups. The co-aggregation of the cells is one of the mechanisms for resistance of LAB to irradiation.

Probiotics for Reduction of Examination Stress in Students (PRESS) study: A randomized, double-blind, placebo-controlled trial of the probiotic Lacticaseibacillus rhamnosus HN001.

BACKGROUND: Studies suggest that bioactive compounds such as probiotics may positively influence psychological health. This study aimed to determine whether supplementation with the probiotic Lacticaseibacillus rhamnosus HN001 reduced stress and improve psychological wellbeing in university students sitting examinations. METHODS: In this randomized, double-blind, placebo-controlled study, 483 undergraduate students received either the probiotic L. rhamnosus HN001, or placebo, daily during a university semester. Students completed measures of stress, anxiety, and psychological wellbeing at baseline and post-intervention before examinations. Mann Whitney U tests compared the change in psychological outcomes between groups. RESULTS: Of the 483 students, 391 (81.0%) completed the post-intervention questions. There was no significant difference between the probiotic and placebo supplemented groups in psychological health outcomes. The COVID19 pandemic restrictions may have influenced the typical trajectory of stress leading up to examinations. CONCLUSION: We found no evidence of significant benefit of probiotics on the psychological health of university students. These findings highlight the challenges of conducting probiotic trials in human populations where the potential for contextual factors such as COVID19 response, and participant adherence to the intervention may influence results.