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Cell Host & Microbe May 2023Acetaminophen (APAP) overdose is a leading cause of drug-induced liver injury (DILI). The impact of the gut microbiota and associated metabolites on APAP and liver...
Acetaminophen (APAP) overdose is a leading cause of drug-induced liver injury (DILI). The impact of the gut microbiota and associated metabolites on APAP and liver function remains unclear. We show that APAP disturbance is associated with a distinct gut microbial community, with notable decreases in Lactobacillus vaginalis. Mice receiving L. vaginalis showed resistance to APAP hepatotoxicity due to the liberation of the isoflavone daidzein from the diet by bacterial β-galactosidase. The hepatoprotective effects of L. vaginalis in APAP-exposed germ-free mice were abolished with a β-galactosidase inhibitor. Similarly, β-galactosidase-deficient L. vaginalis produced poorer outcomes in APAP-treated mice than the wild-type strain, but these differences were overcome with daidzein administration. Mechanistically, daidzein prevented ferroptotic death, which was linked to decreased expression of farnesyl diphosphate synthase (Fdps) that activated a key ferroptosis pathway involving AKT-GSK3β-Nrf2. Thus, liberation of daidzein by L. vaginalis β-galactosidase inhibits Fdps-mediated hepatocyte ferroptosis, providing promising therapeutic approaches for DILI.
Topics: Animals; Mice; Acetaminophen; beta-Galactosidase; Chemical and Drug Induced Liver Injury; Gastrointestinal Microbiome; Isoflavones; Liver; Mice, Inbred C57BL; NF-E2-Related Factor 2
PubMed: 37100057
DOI: 10.1016/j.chom.2023.04.002 -
Frontiers in Microbiology 2021Lactobacilli are the dominant members of the healthy human vaginal microbiota and represent the first defense line from pathogen infection, including vulvovaginal...
Lactobacilli are the dominant members of the healthy human vaginal microbiota and represent the first defense line from pathogen infection, including vulvovaginal candidiasis. Biofilm is the predominant microbial growth form in nature, and the formation of biofilms inside the human body has important implications in health and disease. In particular, the formation of biofilm by members of the human resident microbiota is desirable, as it can improve microbial persistence and influence functionality. In the present study, we investigated the capability of 16 vaginal strains (belonging to , , and species) to form biofilms, and we correlated their mode of growth to anti- activity. strains were the best biofilm producers, and high variability was registered in the level of biofilm formation among and strains. Culture supernatants derived from biofilm and planktonic growth were tested toward a panel of clinical isolates (, , , and ) and their metabolome assessed by H-NMR. and strains exhibited the best fungistatic profile, and biofilms enhanced their anti- activity; on the contrary, strains were more effective when grown in a planktonic mode. Biofilm/planktonic mode of growth also affects metabolism, mainly influencing nitrogen and amino acid pathways, and anti- activity is instead strictly related to carbohydrate metabolism. The present study underlined the strict interdependence between microbial mode of growth, metabolism, and functional properties. Biofilm formation by members of the healthy human microbiota represents a crucial issue in the field of microbial physiology and host-microbiota interactions, beyond supporting the development of new antimycotic strategies based on probiotics grown in adherence.
PubMed: 34777300
DOI: 10.3389/fmicb.2021.750368 -
Frontiers in Immunology 2022Food allergy is a serious public health problem because of its high incidence and risk. Probiotics can induce immune regulation in patients with allergic diseases, but...
Food allergy is a serious public health problem because of its high incidence and risk. Probiotics can induce immune regulation in patients with allergic diseases, but its mechanism is not fully clear. In this paper, β-lactoglobulin (β-LG)-sensitized mice were used as models to explore the mechanism of KV9 (KV9) and FN3 (FN3) on reducing allergic reactions and regulating immune cell function. The results showed that oral administration of KV9 and FN3 significantly reduced the scores of allergic symptoms, hypothermia symptoms, and serum levels of β-LG-specific immunoglobulins E (β-LG-sIgE), histamine, and mast cell protease in allergic mice. Flow cytometry analysis of intestinal dendritic cells (DCs) showed that the proportion of CD11c+major histocompatibility complex (MHC)-II+DCs, CD11c+CD80+DCs, and CD11c+ CD86+DCs increased after KV9 and FN3 intervention, indicating that the strains induced immature DCs and decreased the antigen-presenting capacity of DCs. Meanwhile, the toll-like receptor 4 (TLR4)-NF-κB signaling pathway was activated in DCs. The secretion of interleukin-12 (IL-12) was significantly increased, while interleukin-4 (IL-4) was decreased by DCs after KV9 and FN3 intervention, indicating that DCs have the potential to promote T-cell differentiation into T helper type 1 (Th1) cells. Furthermore, the proportion of CD3+CD8-IFN-γ+ T cells in the spleen increased, while CD3+CD8-IL-4+T cells decreased after oral administration of KV9 and FN3, correcting the T helper type 2 (Th2)-skewed immune responses. These results indicate that KV9 and FN3 reduce β-LG-induced allergic symptoms in mice, and suggest that the two potential probiotics might be used as an alternative therapeutic agent for mitigating food allergy.
Topics: Animals; Bifidobacterium animalis; Dendritic Cells; Food Hypersensitivity; Histamine; Immunoglobulin E; Interleukin-12; Interleukin-4; Lactobacillus; Lactoglobulins; Mice; NF-kappa B; Peptide Hydrolases; Toll-Like Receptor 4
PubMed: 36238281
DOI: 10.3389/fimmu.2022.992605 -
Journal of Medical Microbiology Aug 2012The objectives of the present study were to evaluate in vitro the production of antagonistic compounds against Gardnerella vaginalis by Lactobacillus strains isolated...
The objectives of the present study were to evaluate in vitro the production of antagonistic compounds against Gardnerella vaginalis by Lactobacillus strains isolated from women with or without bacterial vaginosis (BV), and to select one of the better Lactobacillus producers of such a substance to be tested in vivo using a gnotobiotic animal model challenged with one of the more sensitive G. vaginalis isolates. A total of 24 isolates from women with and without BV were identified as G. vaginalis. A higher frequency (P<0.05) of this bacterium was observed in women with BV (56.7%) when compared to healthy women (17.6%). A total of 86 strains of Lactobacillus were obtained from healthy women and women with BV. Lactobacillus strains were more frequently present (P<0.05) in healthy women (97.5%) than in women with BV (76.7%). Lactobacillus crispatus was the predominating strain in both healthy women and women with BV. Lactobacillus jensenii, Lactobacillus johnsonii, Lactobacillus gasseri and Lactobacillus vaginalis were isolated with an intermediate frequency in the two groups. In vitro antagonism assays were performed using as indicators 17 reference strains and the G. vaginalis strains isolated from women with BV and from healthy women. Lactobacillus isolated from healthy women showed the higher antagonistic activity against all the indicator strains when compared with isolates from women with BV. Concerning the indicator strains, G. vaginalis found in women with BV was more resistant to the antagonism, particularly when Lactobacillus isolates from women with BV were used as producer strains. A high vaginal population level of G. vaginalis was obtained by intravaginal inoculation of germ-free mice, and this colonization was accompanied by vaginal histopathological lesions. A tenfold decrease in vaginal population level of G. vaginalis and a reduction of histological lesions were observed when the pathogenic challenge was performed in mice previously monoassociated with an L. johnsonii strain. Concluding, results of the present study suggest that progression of G. vaginalis-associated BV depends in part on a simultaneous presence of Lactobacillus populations with a low antagonistic capacity and of a G. vaginalis strain with a high resistance to this antagonism. The results could also explain why G. vaginalis is frequently found in the vaginal ecosystem of healthy women.
Topics: Adolescent; Adult; Animals; Antibiosis; Bacterial Load; Female; Gardnerella vaginalis; Germ-Free Life; Human Experimentation; Humans; Lactobacillus; Mice; Middle Aged; Vagina; Vaginosis, Bacterial; Young Adult
PubMed: 22539000
DOI: 10.1099/jmm.0.041962-0 -
International Journal of Food... May 2020Histamine, one of the most toxic and commonly encountered biogenic amines (BA) in food, is produced by the microbial decarboxylation of histidine. It may accumulate at...
Histamine, one of the most toxic and commonly encountered biogenic amines (BA) in food, is produced by the microbial decarboxylation of histidine. It may accumulate at high concentrations in fish and fermented food. Cheese has some of the highest histamine concentrations, the result of the histidine-decarboxylase activity of certain lactic acid bacteria (LAB). The present work describes the nucleotide sequence and transcriptional organization of the gene cluster responsible for histamine biosynthesis (the HDC cluster) in Lactobacillus vaginalis IPLA 11064 isolated from cheese. The influence of histidine availability and pH on histamine production and the expression of the HDC cluster genes is also examined. As expected, the results suggest that the production of histamine under acidic conditions improves cell survival by maintaining the cytosol at an appropriate pH. However, the transcriptional regulation of the HDC cluster is quite different from that described in other dairy histamine-producing LAB, probably due to the lack of a termination-antitermination system in the histidyl-tRNA synthetase gene (hisS).
Topics: Animals; Cheese; Cytosol; Gene Expression Regulation, Bacterial; Histamine; Histidine; Histidine Decarboxylase; Hydrogen-Ion Concentration; Lactobacillus; Microbial Viability
PubMed: 32050139
DOI: 10.1016/j.ijfoodmicro.2020.108548 -
Microbiology Resource Announcements Feb 2019The Lactobacillus vaginalis LMG S-26419 strain, also named CBA-L88 (BV2), was isolated at the AAT-Advanced Analytical Technologies laboratories from a vaginal swab...
The Lactobacillus vaginalis LMG S-26419 strain, also named CBA-L88 (BV2), was isolated at the AAT-Advanced Analytical Technologies laboratories from a vaginal swab obtained from a healthy woman. The total genome size is 1,806,242 bp with a G+C content of 40.6%.
PubMed: 30834369
DOI: 10.1128/MRA.01534-18 -
Annals of Palliative Medicine Jan 2022To detect the correlation between Lactobacillus vaginalis and the expression of epithelial-mesenchymal transition (EMT)-related factors, E-cadherin, β-catenin,...
BACKGROUND
To detect the correlation between Lactobacillus vaginalis and the expression of epithelial-mesenchymal transition (EMT)-related factors, E-cadherin, β-catenin, N-cadherin, and Vimentin, in postmenopausal cervical squamous intraepithelial lesions (SILs) and cervical squamous cell carcinoma (SCC), and to explore the possible mechanism.
METHODS
From January 2016 to January 2020, 30 postmenopausal patients with low-grade SIL (LSIL), 18 patients with high-grade SIL (HSIL), and 30 patients with SCC who underwent colposcopy biopsy in the Outpatient Department of the First Affiliated Hospital of Inner Mongolia Medical University were selected as the experimental group, and 30 postmenopausal normal women were selected as the control group. The expression of 16SrRNA of Lactobacillus vaginalis in each group was determined by the 16S third-generation full-length amplification sequencing technique. The mRNA expression levels of E-cadherin, β-catenin, N-cadherin, and Vimentin were detected by quantitative real-time polymerase chain reaction (qPCR). The correlation between the 16SrRNA expression level of Lactobacillus vaginalis and the mRNA expression level of the EMT-related proteins was compared among all groups.
RESULTS
(I) The progression of postmenopausal cervical SILs to cervical SCC was significantly positively correlated with age, number of pregnancies, smoking, pH value, positive rate of HPV16, and negatively correlated with total Lactobacillus 16SrRNA expression (P<0.0001). (II) The level of vaginal microbiota in postmenopausal women showed that Lactobacillus iners was dominant. With the progression of the disease, the expression levels of 16SrRNA in Lactobacillus iners and Lactobacillus total vagina decreased gradually, and the differences were statistically significant (P<0.05). (III) With the disease progresses. The expression of total Lactobacillus 16SrRNA was positively correlated with the mRNA expression of β-catenin and E-cadherin (r>0; P<0.05), and negatively correlated with the mRNA expression of Vimentin and N-cadherin (r<0; P<0.05).
CONCLUSIONS
In postmenopausal women, Lactobacillus vaginalis interacts with HPV and is associated with the occurrence of EMT, promoting the development of cervical lesions.
Topics: Alphapapillomavirus; Cadherins; Epithelial-Mesenchymal Transition; Female; Humans; Lactobacillus; Postmenopause; Pregnancy; Uterine Cervical Diseases; Vimentin; beta Catenin
PubMed: 35144405
DOI: 10.21037/apm-21-3581 -
British Journal of Pharmacology Jan 2024Membranous nephropathy (MN) is an immune-mediated glomerular disease in adults. Antibody- and antigen-bonding mechanisms have been largely clarified, but the...
BACKGROUND AND PURPOSE
Membranous nephropathy (MN) is an immune-mediated glomerular disease in adults. Antibody- and antigen-bonding mechanisms have been largely clarified, but the subepithelium immune complex deposition-mediated downstream molecular mechanisms are currently unresolved. Increasing evidence has suggested that gut microbiota contribute to MN pathogenesis.
EXPERIMENTAL APPROACH
In this study, we identified alterations in faecal gut microbiota and serum metabolites that mediate an aryl hydrocarbon receptor (AhR) mechanism in cationic bovine serum albumin (CBSA)-induced MN rats and in patients with idiopathic MN (IMN).
KEY RESULTS
Impaired renal function correlated with the relative abundance of reduced faecal probiotics, Lactobacillus and Bifidobacterium, and altered serum levels of tryptophan-produced indole derivatives (TPIDs) in MN rats. Further results showed that reduced relative abundance of five probiotics, namely Lactobacillus johnsonii, Lactobacillus murinus, Lactobacillus vaginalis, Lactobacillus reuteri and Bifidobacterium animalis, positively correlated with decreased levels of indole-3-pyruvic acid, indole-3-aldehyde and tryptamine and negatively correlated with increased levels of indole-3-lactic acid and indole-3-acetic acid in serum of MN rats. Altered five probiotics and five TPIDs also were observed in patients with IMN. Further studies showed that MN rats exhibited a significant increase in intrarenal mRNA expression of AhR and its target genes CYP1A1, CYP1A2 and CYP1B1, which were accompanied by protein expression of down-regulated cytoplasmic AhR, but up-regulated nuclear AhR, in MN rats and IMN patients.
CONCLUSION AND IMPLICATIONS
Activation of the intrarenal AhR signalling pathway may involve five TPIDs. These data suggest that gut microbiota could influence MN through TPIDs that engage host receptors.
Topics: Lactobacillus; Glomerulonephritis, Membranous; Tryptophan; Indoles; Receptors, Aryl Hydrocarbon; Humans; Animals; Rats; Male; Rats, Sprague-Dawley; Gastrointestinal Microbiome; Signal Transduction
PubMed: 37594378
DOI: 10.1111/bph.16219 -
International Journal of Food... Dec 2015In food, the biogenic amine (BA) histamine is mainly produced by histidine decarboxylation catalysed by microbial histidine decarboxylase. The consumption of foods...
In food, the biogenic amine (BA) histamine is mainly produced by histidine decarboxylation catalysed by microbial histidine decarboxylase. The consumption of foods containing high concentrations of histamine can trigger adverse neurological, gastrointestinal and respiratory reactions. Indeed, histamine is one of the most toxic of all BAs, and is often detected in high concentration in cheese. However, little is known about the microorganisms responsible for its accumulation in this food. In the present work, 25 histamine-producing Lactobacillus vaginalis strains were isolated from a blue-veined cheese (the first time that histamine-producing strains of this species have been isolated from any food). The restriction profiles of their genomes were analysed by PFGE, and seven lineages identified. The presence of the histidine decarboxylase gene (hdcA) was confirmed by PCR. The nucleotide sequence and genetic organisation of the histamine biosynthesis gene cluster (HDC) and its flanking regions are described for a representative strain (L. vaginalis IPLA11050).
Topics: Bacterial Typing Techniques; Base Sequence; Cheese; DNA, Bacterial; Electrophoresis, Gel, Pulsed-Field; Food Microbiology; Histamine; Histidine Decarboxylase; Lactobacillus; Multigene Family; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 26394683
DOI: 10.1016/j.ijfoodmicro.2015.08.026 -
The American Journal of Tropical... 2000D2A21, a novel peptide antibiotic has in vitro activity against a wide spectrum of sexually transmitted diseases (STD). In this study we tested the hypothesis that...
D2A21, a novel peptide antibiotic has in vitro activity against a wide spectrum of sexually transmitted diseases (STD). In this study we tested the hypothesis that intravaginal D2A21 would interfere with acquisition of Trichomonas vaginalis infection in a modified mouse model. T. vaginalis infections of estrogenized young mice pretreated with Lactobacillus vaginalis or Lactobacillus rhamnosus were more frequent and persistent than those in mice pre-treated with Lactobacillus gasseri or Lactobacillus acidophilus. One hundred percent T. vaginalis infection was achieved for 2-4 days post-challenge when intravaginal L. rhamnosus pre-treatments were given to estrogenized mice 48 hr prior to a single T. vaginalis challenge. Estrogenized mice pre-treated with L. rhamnosus were pre-medicated with intravaginal placebo gel, 0.5% or 2% D2A21 gel, or 500 microg/mL metronidazole gel prior to T. vaginalis challenge. Both 2% D2A21 and metronidazole gels were significantly more efficacious (10% or none infected) than placebo gel (53% infected) in preventing vaginal T. vaginalis infections in mice.
Topics: Administration, Intravaginal; Animals; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Disease Models, Animal; Estrogens; Female; Gels; Lactobacillus; Metronidazole; Mice; Mice, Inbred BALB C; Peptides; Trichomonas Vaginitis; Trichomonas vaginalis
PubMed: 11421379
DOI: No ID Found