Disruption of urogenital biofilms by lactobacilli

Antibiofilm Agents for the Treatment and Prevention of Bacterial Vaginosis: A Systematic Narrative Review

BACKGROUND

Bacterial vaginosis (BV) is difficult to eradicate due to BV biofilms protecting BV bacteria (Gardnerella, Prevotella, and other genera). With the growing understanding of biofilms, we systematically reviewed the current knowledge on the efficacy of anti-BV biofilm agents.

METHODS

We searched literature in the Scopus, Medline, and Embase databases for empirical studies investigating substances for the treatment of BV biofilms or prevention of their recurrence and their efficacy and/or safety.

RESULTS

Of 201 unique titles, 35 satisfied the inclusion criteria. Most studies (89%) reported on preclinical laboratory research on the efficacy of experimental antibiofilm agents (80%) rather than their safety. Over 50% were published within the past 5 years. Agents were classified into 7 groups: antibiotics, antiseptics, cationic peptides, enzymes, plant extracts, probiotics, and surfactants/surfactant components. Enzymes and probiotics were most commonly investigated. Earlier reports of antibiotics having anti-BV biofilm activity have not been confirmed. Some compounds from other classes demonstrated promising anti-BV biofilm efficacy in early studies.

CONCLUSIONS

Further research is anticipated on successful antibiofilm agents. If confirmed as effective and safe in human clinical trials, they may offer a breakthrough in BV treatment. With rising antibiotic resistance, antibiofilm agents will significantly improve the current standard of care for BV management.

Altered microbial diversity and composition of multiple mucosal organs in cervical cancer patients

OBJECTIVES

The aim of this study was to characterize the microbiome of multiple mucosal organs in cervical cancer (CC) patients.

METHODS

We collected oral, gut, urinary tract, and vaginal samples from enrolled study participants, as well as tumor tissue from CC patients. The microbiota of different mucosal organs was identified by 16S rDNA sequencing and correlated with clinical-pathological characteristics of cervical cancer cases.

RESULTS

Compared with controls, CC patients had reduced α-diversity of oral and gut microbiota (pOral_Sob < 0.001, pOral_Shannon = 0.049, pOral_Simpson = 0.013 pFecal_Sob = 0.030), although there was an opposite trend in the vaginal microbiota (pVaginal_Pielou = 0.028, pVaginal_Simpson = 0.006). There were also significant differences in the β-diversity of the microbiota at each site between cases and controls (pOral = 0.002, pFecal = 0.037, pUrine = 0.001, pVaginal = 0.001). The uniformity of urine microbiota was lower in patients with cervical squamous cell carcinoma (pUrine = 0.036) and lymph node metastasis (pUrine_Sob = 0.027, pUrine_Pielou = 0.028, pUrine_Simpson = 0.021, pUrine_Shannon = 0.047). The composition of bacteria in urine also varied among patients with different ages (p = 0.002), tumor stages (p = 0.001) and lymph node metastasis (p = 0.002). In CC cases, Pseudomonas were significantly enriched in the oral, gut, and urinary tract samples. In addition, Gardnerella, Anaerococcus, and Prevotella were biomarkers of urinary tract microbiota; Abiotrophia and Lautropia were obviously enriched in the oral microbiota. The microbiota of tumor tissue correlated with other mucosal organs (except the gut), with a shift in the microflora between mucosal organs and tumors.

CONCLUSIONS

Our study not only revealed differences in the composition and diversity of the vaginal and gut microflora between CC cases and controls, but also showed dysbiosis of the oral cavity and urethra in cervical cancer cases.

It Is All about Probiotics to Control Cervical Cancer

Cervical cancer (CC) is the fourth most common malignancy in female patients. "Human papillomavirus" (HPV) contamination is a leading cause of all forms of cervical cancer, accounting for an expected 570,000 reported incidents in 2018. Two HPV strains (16 and 18) are responsible for 70% of CC and pre-cancerous cervical abnormalities. CC is one of the foremost reasons for the malignancy death rate in India among women ranging from 30 to 69 years of age in India, responsible for 17% of all cancer deaths. Currently approved cervical cancer treatments are associated with adverse reactions that might harm the lives of women affected by this disease. Consequently, probiotics can play a vital role in the treatment of CC. It is reflected from various studies regarding the role of probiotics in the diagnosis, prevention or treatment of cancer. In this review article, we have discussed the rationale of probiotics for treatment of CC, the role of probiotics as effective adjuvants in anti-cancer therapy and the combined effect of the anti-cancer drug along with probiotics to minimize the side effects due to chemotherapy.

Leveraging existing 16S rRNA gene surveys to decipher microbial signatures and dysbiosis in cervical carcinogenesis

The presence of dysbiotic cervicovaginal microbiota has been observed to be linked to the persistent development of cervical carcinogenesis mediated by the human papillomavirus (HPV). Nevertheless, the characteristics of the cervical microbiome in individuals diagnosed with cervical cancer (CC) are still not well understood. Comprehensive analysis was conducted by re-analyzing the cervical 16S rRNA sequencing datasets of a total of 507 samples from six previously published studies. We observed significant alpha and beta diversity differences in between CC, cervical intraepithelial neoplasia (CIN) and normal controls (NC), but not between HPV and NC in the combined dataset. Meta-analysis revealed that opportunistic pernicious microbes Streptococcus, Fusobacterium, Pseudomonas and Anaerococcus were enriched in CC, while Lactobacillus was depleted compared to NC. Members of Gardnerella, Sneathia, Pseudomonas, and Fannyhessea have significantly increased relative abundance compared to other bacteria in the CIN group. Five newly identified bacterial genera were found to differentiate CC from NC, with an area under the curve (AUC) of 0.8947. Moreover, co-occurrence network analysis showed that the most commonly encountered Lactobacillus was strongly negatively correlated with Prevotella. Overall, our study identified a set of potential biomarkers for CC from samples across different geographic regions. Our meta-analysis provided significant insights into the characteristics of dysbiotic cervicovaginal microbiota undergoing CC, which may lead to the development of noninvasive CC diagnostic tools and therapeutic interventions.

The role of probiotics as adjunct treatment in the prevention and management of gynecological infections: An updated meta-analysis of 35 RCT studies

OBJECTIVE

The present study aims to conduct a comprehensive meta-analysis of randomized controlled trials (RCTs) investigating the efficacy of probiotics as an adjunct treatment for preventing and treating gynecological infections.

MATERIALS AND METHODS

The study adopted a systematic review of scientific databases including PubMed, Cochrane, and EMBASE, using defined MeSH terms. The inclusion and exclusion criteria were set to refine the search, with the data extraction and quality assessment being conducted by two independent investigators.

RESULTS

A total of 35 articles, comprising 3751 patients, were included in the meta-analysis. The application of probiotics demonstrated a notable increase in the cure rates of bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC) as compared to control groups. A significant BV cure rate (OR: 5.972; 95% CI: 2.62-13.59; p-value: 0.01) was noted with probiotic use, which was even more pronounced when used as an adjunctive treatment with antibiotics (OR: 2.504; 95% CI: 1.03-6.06; p-value: 0.04). Additionally, probiotic use significantly reduced the recurrence rates of BV (OR: 0.34; 95% CI: 0.167-0.71; p-value: 0.004). For VVC, a significant increase in the cure rate was observed in the probiotic group (OR: 3.425; 95% CI: 2.404-4.879; p-value: 0.01), along with a lower recurrence rate (OR: 0.325; 95% CI: 0.175-0.606; p-value: 0.01).

CONCLUSION

Our findings underscore the potential role of probiotics as a beneficial adjunctive treatment for gynecological infections, indicating an improved cure rate and decreased recurrence. However, additional well-designed studies are necessary to corroborate these findings.

Molecular Aspects of the Functioning of Pathogenic Bacteria Biofilm Based on Quorum Sensing (QS) Signal-Response System and Innovative Non-Antibiotic Strategies for Their Elimination

One of the key mechanisms enabling bacterial cells to create biofilms and regulate crucial life functions in a global and highly synchronized way is a bacterial communication system called quorum sensing (QS). QS is a bacterial cell-to-cell communication process that depends on the bacterial population density and is mediated by small signalling molecules called autoinducers (AIs). In bacteria, QS controls the biofilm formation through the global regulation of gene expression involved in the extracellular polymeric matrix (EPS) synthesis, virulence factor production, stress tolerance and metabolic adaptation. Forming biofilm is one of the crucial mechanisms of bacterial antimicrobial resistance (AMR). A common feature of human pathogens is the ability to form biofilm, which poses a serious medical issue due to their high susceptibility to traditional antibiotics. Because QS is associated with virulence and biofilm formation, there is a belief that inhibition of QS activity called quorum quenching (QQ) may provide alternative therapeutic methods for treating microbial infections. This review summarises recent progress in biofilm research, focusing on the mechanisms by which biofilms, especially those formed by pathogenic bacteria, become resistant to antibiotic treatment. Subsequently, a potential alternative approach to QS inhibition highlighting innovative non-antibiotic strategies to control AMR and biofilm formation of pathogenic bacteria has been discussed.

Lactobacilli and Klebsiella: Two Opposites in the Fight for Human Health

The problem of antibiotic resistance is currently very acute. Numerous research and development of new antibacterial drugs are being carried out that could help cope with various infectious agents. One of the promising directions for the search for new antibacterial drugs is the search among the probiotic strains present in the human gastrointestinal tract. This review is devoted to characteristics of one of these probiotic strains that have been studied to date: Limosilactobacillus reuteri. The review discusses its properties, synthesis of various compounds, as well as role of this strain in modulating various systems of the human body. The review also examines key characteristics of one of the most harmful among the currently known pathogenic organisms, Klebsiella, which is significantly resistant to antibiotics existing in medical practice, and also poses a great threat of nosocomial infections. Discussion of characteristics of the two strains, which have opposite effects on human health, may help in creation of new effective antibacterial drugs without significant side effects.

ESKAPEE Pathogen Biofilm Control on Surfaces with Probiotic Lactobacillaceae and Bacillus species

Combatting the rapidly growing threat of antimicrobial resistance and reducing prevalence and transmission of ESKAPEE pathogens in healthcare settings requires innovative strategies, one of which is displacing these pathogens using beneficial microorganisms. Our review comprehensively examines the evidence of probiotic bacteria displacing ESKAPEE pathogens, with a focus on inanimate surfaces. A systematic search was conducted using the PubMed and Web of Science databases on 21 December 2021, and 143 studies were identified examining the effects of Lactobacillaceae and Bacillus spp. cells and products on the growth, colonization, and survival of ESKAPEE pathogens. While the diversity of study methods limits evidence analysis, results presented by narrative synthesis demonstrate that several species have the potential as cells or their products or supernatants to displace nosocomial infection-causing organisms in a variety of in vitro and in vivo settings. Our review aims to aid the development of new promising approaches to control pathogen biofilms in medical settings by informing researchers and policymakers about the potential of probiotics to combat nosocomial infections. More targeted studies are needed to assess safety and efficacy of different probiotic formulations, followed by large-scale studies to assess utility in infection control and medical practice.

Impact of cervicovaginal microbiome on the risk of cervical abnormalities development

The vaginal microbiome has emerged as potentially influencing the natural history of Human Papillomavirus (HPV) infections and their clinical impact. We aimed to characterize the vaginal microbiome in samples from 807 high-risk HPVs (Hr-HPV) positive women with a mean age of 41.45 ± 10.79 years who participated in the Regional Cervical Cancer Screening Program from the Northern Region of Portugal. Microbiome analysis was performed with commercial kits for the detection of 21 microorganisms. The most frequent microorganisms were Ureaplasma parvum (52.5%), Gardnerella vaginalis (GV) (34.5%), Atopobium vaginae (AV) (32.6%), Lacto (30.7%), and Mycoplasma hominis (MH) (23.5%). The distribution according to age reveals that MH, Mega1, GV, BVab2, AV, and Mob were more prevalent in women older than 41 years of age (p < 0.050), while Lacto is significantly decreased in this group (23.5% vs. 39.4%, p < 0.001; RR = 0.47). The risk analysis showed that Hr-HPV-16/-18 and Hr-HPV-9val genotypes are associated with an increased risk of developing cervical abnormalities, while Lacto (p < 0.001; odd ratio [OR] = 0.33), GV (p = 0.0111; OR = 0.41), AV (p = 0.033; OR = 0.53) and Mob (p = 0.022; OR = 0.29) are associated with protection. Similar results were found for the risk of development atypical squamous cells cannot exclude HSIL/high-grade squamous intraepithelial lesion. Overall, the multivariate analysis confirmed that lactobacillus and bacteria associated with bacterial vaginosis (GV, AV, and Mob) are associated with protection against the development of cervical abnormalities. This study provides important data to be included in the future management of risk stratification for Hr-HPV-positive women.

Vaginal microbiome and cervical cancer

The female reproductive tract, similar to other mucosal sites, harbors a specific microbiome commonly dominated by Lactobacillus species (spp.), which has an essential role in maintaining health and homeostasis. Increasing evidence shows that genital tract dysbiosis and/or specific bacteria and cytokines might have an active role in the development and/or progression of HPV infection and cervical intra-epithelial neoplasia (CIN) and as a result cervical cancer. Cross-sectional and longitudinal studies reported that Lactobacillus spp. depletion increases with severity of CIN and that this may negatively affect disease regression rates. It is plausible that Lactobacillus deplete microbiome composition may lead to a pro-inflammatory environment that can increase malignant cell proliferation and HPV E6 and E7 oncogene expression. Future longitudinal cohorts and mechanistic experiments on HPV transfected cells models will further permit exploration of the impact of Lactobacillus spp. on HPV infection.

Lactic Acid Bacteria: A Promising Tool for Menopausal Health Management in Women

Menopause is a period during which women undergo dramatic hormonal changes. These changes lead to physical and mental discomfort, are greatly afflictive, and critically affect women's lives. However, the current safe and effective management measures for women undergoing menopause are insufficient. Several probiotic functions of lactic acid bacteria (LAB) have been recognized, including alleviation of lactose intolerance, protection of digestive tract health, activation of the immune system, protection against infections, improvement of nutrient uptake, and improvement of the microbiota. In this review, we highlight the currently available knowledge of the potential protective effects of LAB on preventing or mitigating menopausal symptoms, particularly in terms of maintaining balance in the vaginal microbiota, reducing bone loss, and regulating the nervous system and lipid metabolism. Given the increasing number of women entering menopause and the emphasis on the management of menopausal symptoms, LAB are likely to soon become an indispensable part of clinical/daily care for menopausal women. Herein, we do not intend to provide a comprehensive analysis of each menopausal disorder or to specifically judge the reliability and safety of complementary therapies; rather, we aim to highlight the potential roles of LAB in individualized treatment strategies for the clinical management of menopause.

Observation of the cervical microbiome in the progression of cervical intraepithelial neoplasia

OBJECTIVE

Cervical microbial community in the cervical intraepithelial neoplasia and cervical cancer patients was analysed to study its composition, diversity and signalling pathways by high-throughput 16S rDNA sequencing,and the candidate genes associated with occurrence and progression of cervical intraepithelial neoplasia were screened out and the model was established to predict the evolution of cervical intraepithelial neoplasia malignant transformation from the cervical microbial genes aspect.

METHODS

Cervical tissues of normal, cervical intraepithelial neoplasia and cervical cancer patients without receiving any treatment were collected. The correlation between candidate genes and cervical intraepithelial neoplasia progression was initially determined by analyzing the microbial flora. Real-time fluorescence quantitative PCR was used to detect the expression of candidate genes in different cervical tissues, ROC curve and logistic regression was used to analyse and predict the risk factors related to the occurrence and progression of cervical intraepithelial neoplasia. Finally, the early warning model of cervical intraepithelial neoplasia occurrence and progression is established.

RESULTS

Cervical tissues from normal, cervical intraepithelial neoplasia and cervical cancer patients were collected for microbial community high-throughput 16S rDNA sequencing. The analysis revealed five different pathways related to cervical intraepithelial neoplasia. 10 candidate genes were selected by further bioinformatics analysis and preliminary screening. Real time PCR, ROC curve and Logistic regression analysis showed that human papillomavirus infection, TCT severity, ABCG2, TDG, PCNA were independent risk factors for cervical intraepithelial neoplasia. We used these indicators to establish a random forest model. Seven models were built through different combinations. The model 4 (ABCG2 + PCNA + TDG) was the best early warning model for the occurrence and progression of CIN.

CONCLUSIONS

A total of 5 differential pathways and 10 candidate genes related to occurrence and progression of cervical intraepithelial neoplasia were found in cervical microbial community. This study firstly identified the genes from cervical microbial community that play an important role in the occurrence and progression of cervical intraepithelial neoplasia. At the same time, the early warning model including ABCG2 + PCNA+TDG genes provided a new idea and target for clinical prediction and blocking the evolution of cervical intraepithelial neoplasia malignant transformation from the aspect of cervical microbiological related genes.

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

Background

The goal of this study was to investigate the effects of treatment with Saccharomyces boulardii and Lactobacillus reuteri on the eradication of Helicobacter pylori and Adverse effects (AEs) of the treatment.

Results

This study was a double-blind, randomized, placebo-controlled trial. And, eradication of H. pylori was reported comparing quadruple therapy include of PPI (proton pomp inhibitor), bismuth subcitrate, clarithromycin, and amoxicillin versus quadruple therapy supplemented with S. boulardii and L. reuteri DSMZ 17648. For this aim, a total of 156 patients were included in the current study; and patients positive for H. pylori infection (n = 156) were randomly assigned to 3 groups: 52 patients (Group P) received conventional quadruple therapy plus L. reuteri, 52 patients (Group S) received conventional quadruple therapy plus S. boulardii daily, for 2 weeks, and 52 patients were in the control group (Group C). At the end of the treatment period, all the subjects continued to take proton pump inhibitor (PPI) alone for 14 days, and then, no medication was given for 2 weeks again. During follow-up, gastrointestinal symptoms were assessed using an evaluation scale (Glasgow dyspepsia questionnaire [GDQ]), and AEs were assessed at 7, 14, 21, and 28 days. As a result, all patients completed the treatment protocol in all groups by the end of the study. Additionally, eradication therapy was effective for 94.2% of subjects in Group S, 92.3% of subjects in Group P, and 86.5% of subjects in the control group, with no differences between treatment arms. In Group S, the chance of developing symptoms of nausea (OR = 2.74), diarrhea (OR = 3.01), headache (OR = 10.51), abdominal pain (OR = 3.21), and anxiety (OR = 3.58) was significantly lower than in the control group (p < 0.05).

Conclusion

S. boulardii could significantly reduce some AEs of H. pylori eradication therapy, but effectiveness of Lactobacillus reuteri on these cases was not significant. It is recommended to conduct the future research with larger sample size in order to investigate the effect.

Trial registration: IRCT20200106046021N1, this trial was registered on Jan 14, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02187-z.

Characteristics of Gut Microbiota in Female Patients with Diabetic Microvascular Complications

OBJECTIVE

To explore the characteristics and analyze the gut microbiota in female patients with diabetic microvascular complications (DMC).

METHODS

Thirty-seven female patients with type 2 diabetes mellitus (T2DM) were included in the study. These patients were divided into DM group with microvascular complications (T2DM-MC, n = 17) and no microvascular complications group (T2DM-0, n = 20). Patients in the microvascular group presented with the involvement of at least one of the following: kidney, retinal, or peripheral nerves. Using real-time fluorescence quantitative polymerase chain reaction, fecal samples from the two groups were tested for Bacteroides, Prevotella, Bifidobacterium spp, Lactobacillus, Faecalibacterium prausnitzii, Enterococcus spp, Eubacterium rectale, Veillonellaceae, Clostridium leptum, and Roseburia inulinivorans. Levels of fasting and 2 h postprandial blood glucose, glycosylated hemoglobin (HbA1c), lipids, and creatinine were determined to explore the correlation between gut microbiota and blood sugar. Mann-Whitney U test was used to analyze the differences between the two groups. Spearman correlation analysis was used to determine the correlation between gut microbiota and blood glucose. Multifactor logistic regression was used to analyze the risk factors for DMC.

RESULTS

The HbA1c levels in the T2DM-MC group were higher than those in the T2DM-0 group. The abundances of Bacteroides and Enterococcus spp in the T2DM-MC group were higher than that in the T2DM-0 group. The abundances of Bacteroides and Enterococcus spp in the T2DM-MC group were lower than that in the T2DM-0 group. Spearman's correlation analysis showed that Bacteroides, Prevotella, Lactobacillus, C. leptum, and R. inulinivorans were related to the levels of HbA1c or blood glucose (p < 0.05). Logistic regression analysis showed that after adjusting for confounding factors such as age, body mass index, family history, HbA1c, hypertension, dyslipidemia, and creatinine, Bacteroides remained an independent risk factor in female patients with DMC.

CONCLUSION

Gut microbiota is related to blood glucose levels. Female patients with DMC experience gut microbiota disorders. The abundances of Bacteroidesare related to DMC, and the abundances of intestinal flora may affect the blood sugar levels of the body.

Correlation between vaginal microbiota and different progression stages of cervical cancer

The process from high-risk human papillomavirus (HR-HPV) infection to cervical cancer is a continuous and long-term process, but the pathogenesis of the whole process is not completely clear. Here, 59 Chinese women were engaged in this study, and divided into five groups: normal healthy group, HR-HPV infections group, low-grade intraepithelial neoplasia (LSIL) group, high-SIL(HSIL) group, and cervical cancer group. With the occurrence of HR-HPV infection and the development of cervical lesions, the diversity of vaginal microbiota species was increased, and the relative abundance of Lactobacillus (L.), the dominant bacteria in maintaining vaginal microecological balance, was decreased gradually. In contrast, the abundance of Actinobacteria in the four disease groups was significantly higher than that in normal group. Furthermore L. iners may be related to the serious progression of cervical cancer. After analyzing the whole process, we found that Gardnerella(G.), Atopobium(A.) and Dialister(D.) have important effects on both persistent HR-HPV infection and the pathogenesis of cervical cancer. In addition, PICRUSt2 and KEGG results showed that the KEGG pathways enriched by the predicted genes of vaginal microbiota in cancer group included metabolic diseases, endocrine system and immune systems when compared with that in normal group. These findings may provide insights into the pathogenesis of cervical cancer, and help to improve the early detection and prevention of cervical precancerous lesions.

Using Lactobacilli to Fight Escherichia coli and Staphylococcus aureus Biofilms on Urinary Tract Devices

The low efficacy of conventional treatments and the interest in finding natural-based approaches to counteract biofilm development on urinary tract devices have promoted the research on probiotics. This work evaluated the ability of two probiotic strains, Lactobacillus plantarum and Lactobacillus rhamnosus, in displacing pre-formed biofilms of Escherichia coli and Staphylococcus aureus from medical-grade silicone. Single-species biofilms of 24 h were placed in contact with each probiotic suspension for 6 h and 24 h, and the reductions in biofilm cell culturability and total biomass were monitored by counting colony-forming units and crystal violet assay, respectively. Both probiotics significantly reduced the culturability of E. coli and S. aureus biofilms, mainly after 24 h of exposure, with reduction percentages of 70% and 77% for L. plantarum and 76% and 63% for L. rhamnosus, respectively. Additionally, the amount of E. coli biofilm determined by CV staining was maintained approximately constant after 6 h of probiotic contact and significantly reduced up to 67% after 24 h. For S. aureus, only L. rhamnosus caused a significant effect on biofilm amount after 6 h of treatment. Hence, this study demonstrated the potential of lactobacilli to control the development of pre-established uropathogenic biofilms.

Finding a Balance in the Vaginal Microbiome: How Do We Treat and Prevent the Occurrence of Bacterial Vaginosis?

Bacterial vaginosis (BV) has been reported in one-third of women worldwide at different life stages, due to the complex balance in the ecology of the vaginal microbiota. It is a common cause of abnormal vaginal discharge and is associated with other health issues. Since the first description of anaerobic microbes associated with BV like Gardnerella vaginalis in the 1950s, researchers have stepped up the game by incorporating advanced molecular tools to monitor and evaluate the extent of dysbiosis within the vaginal microbiome, particularly on how specific microbial population changes compared to a healthy state. Moreover, treatment failure and BV recurrence rate remain high despite the standard antibiotic treatment. Consequently, researchers have been probing into alternative or adjunct treatments, including probiotics or even vaginal microbiota transplants, to ensure successful treatment outcomes and reduce the colonization by pathogenic microbes of the female reproductive tract. The current review summarizes the latest findings in probiotics use for BV and explores the potential of vaginal microbiota transplants in restoring vaginal health.

The Complex Link between the Female Genital Microbiota, Genital Infections, and Inflammation

The female genital tract microbiota is part of a complex ecosystem influenced by several physiological, genetic, and behavioral factors. It is uniquely linked to a woman's mucosal immunity and plays a critical role in the regulation of genital inflammation. A vaginal microbiota characterized by a high abundance of lactobacilli and low overall bacterial diversity is associated with lower inflammation. On the other hand, a more diverse microbiota is linked to high mucosal inflammation levels, a compromised genital epithelial barrier, and an increased risk of sexually transmitted infections and other conditions. Several bacterial taxa such as Gardnerella spp., Prevotella spp., Sneathia spp., and Atopobium spp. are well known to have adverse effects; however, the definitive cause of this microbial dysbiosis is yet to be fully elucidated. The aim of this review is to discuss the multiple ways in which the microbiota influences the overall genital inflammatory milieu and to explore the causes and consequences of this inflammatory response. While there is abundant evidence linking a diverse genital microbiota to elevated inflammation, understanding the risk factors and mechanisms through which it affects genital health is essential. A robust appreciation of these factors is important for identifying effective prevention and treatment strategies.

Lacticaseibacillus rhamnosus GR-1, a.k.a. Lactobacillus rhamnosus GR-1: Past and Future Perspectives

Lacticaseibacillus rhamnosus GR-1 (LGR-1) (previously classified as Lactobacillus rhamnosus GR-1) is the most researched probiotic strain for women's health. Its various urogenital health effects, including a reduction in the recurrence of bacterial vaginosis and urinary-tract infection, are well documented. The strain has also been safely used by HIV-positive subjects, a portion of whom have reported reduced diarrhea and increased CD4 counts. Unlike most probiotic strains used for urogenital health, LGR-1 has been extensively studied for its properties, including its genomic and metabolic traits and its surface properties. This review aims to highlight the totality of research performed with LGR-1, to act as a rigorous scientific benchmark for probiotic microbes, especially for application to women's health.

Probiotic Lactobacillus sp. Strains Inhibit Growth, Adhesion, Biofilm Formation, and Gene Expression of Bacterial Vaginosis-Inducing Gardnerella vaginalis

Gardnerella vaginalis contributes significantly to bacterial vaginosis, which causes an ecological imbalance in vaginal microbiota and presents with the depletion of Lactobacillus sp. Lactobacillus supplementation was reported to be an approach to treat bacterial vaginosis. We investigated the applicability of three Lactobacillus sp. strains (Lactobacillus delbrueckii DM8909, Lactiplantibacillus plantarum ATCC14917, and Lactiplantibacillus plantarum ZX27) based on their probiotic abilities in vitro. The three candidate Lactobacillus sp. strains for bacterial vaginosis therapy showed distinct properties in auto-aggregation ability, hydrophobicity, adhesion to cervical epithelial cells, and survivability in 0.01% hydrogen peroxide. Lpb. plantarum ZX27 showed a higher yield in producing short-chain fatty acids and lactic acid among the three candidate strains, and all three Lactobacillus sp. strains inhibited the growth and adhesion of G. vaginalis. Furthermore, we discovered that the culture supernatant of Lactobacillus sp. exhibited anti-biofilm activity against G. vaginalis. In particular, the Lpb. plantarum ZX27 supernatant treatment decreased the expression of genes related to virulence factors, adhesion, biofilm formation, metabolism, and antimicrobial resistance in biofilm-forming cells and suspended cells. Moreover, Lactobacillus sp. decreased the upregulated expression of interleukin-8 in HeLa cells induced by G. vaginalis or hydrogen peroxide. These results demonstrate the efficacy of Lactobacillus sp. application for treating bacterial vaginosis by limiting the growth, adhesion, biofilm formation, and virulence properties of G. vaginalis.

Lactobacillus cell-free supernatant as a novel bioagent and biosurfactant against Pseudomonas aeruginosa in the prevention and treatment of orthopedic implant infection

The hypothesis was that probiotic Lactobacillus species (spp.) or their cell-free supernatant (CFS) are effective in inhibiting (a) planktonic growth of Pseudomonas aeruginosa (PA), (b) its adhesion to a Ti6Al4V-alloy surface, and (c) in dispersing biofilm once formed. (a) A planktonic co-culture containing PA(10⁴  colony-forming unit [CFU]/ml) was combined with either Lactobacillus acidophilus, Lactobacillus plantarum (LP), or Lactobacillus fermentum (LF) at a suspension of 10⁴ (1:1) or 10⁸  CFU/ml (1:2). Lactobacillus and PA CFUs were then quantified. (b) Ti-6Al-4V discs were inoculated with PA followed by supplementation with CFS and adherent PA quantified. (c) Biofilm covered discs were supplemented with Lactobacillus CFS and remaining PA activity quantified. Results showed that whole-cell cultures were ineffective in preventing PA growth; however, the addition of CFS resulted in a 99.99 ± 0.003% reduction in adherent PA in all Lactobacillus groups (p < .05 in all groups) with no viable PA growth measured in the LF and LP groups. Following PA biofilm formation, CFS resulted in a significant reduction in PA activity in all Lactobacillus groups (p ≤ .05 in all groups) with a 29.75 ± 15.98% increase measured in control samples. Supplementation with CFS demonstrated antiadhesive, antibiofilm, and toxic properties to PA.

The Use of Probiotics to Fight Biofilms in Medical Devices: A Systematic Review and Meta-Analysis

Medical device-associated infections (MDAI) are a critical problem due to the increasing usage of medical devices in the aging population. The inhibition of biofilm formation through the use of probiotics has received attention from the medical field in the last years. However, this sparse knowledge has not been properly reviewed, so that successful strategies for biofilm management can be developed. This study aims to summarize the relevant literature about the effect of probiotics and their metabolites on biofilm formation in medical devices using a PRISMA-oriented (Preferred Reporting Items for Systematic reviews and Meta-Analyses) systematic search and meta-analysis. This approach revealed that the use of probiotics and their products is a promising strategy to hinder biofilm growth by a broad spectrum of pathogenic microorganisms. The meta-analysis showed a pooled effect estimate for the proportion of biofilm reduction of 70% for biosurfactants, 76% for cell-free supernatants (CFS), 77% for probiotic cells and 88% for exopolysaccharides (EPS). This review also highlights the need to properly analyze and report data, as well as the importance of standardizing the in vitro culture conditions to facilitate the comparison between studies. This is essential to increase the predictive value of the studies and translate their findings into clinical applications.

Understanding the potential of lactobacilli in recurrent UTI prevention

Urinary tract infections (UTIs) are one of the most common infections in women. The only proven preventive strategy for recurrent UTIs is prophylactic antibiotics. Given growing antibiotic resistance, the use of probiotics has been proposed as an alternative to antibiotics. Herein, we discuss the current evidence to support the possibility that exogenous lactobacilli may limit the pathogenicity of uropathogens such as E. coli. Probiotics appear to have a significant potential in prevention of recurrent UTI, however, additional data are needed to understand how they can be effectively used in clinical practice.

Efficacy of an orally administered combination of Lactobacillus paracasei LC11, cranberry and D-mannose for the prevention of uncomplicated, recurrent urinary tract infections in women

BACKGROUND

Most women experience a urinary tract infection (UTI) at least once in their lifetime. The present study determined the efficacy and safety of a combination of Lactobacillus paracasei LC11, cranberry and D-mannose (Lactoflorene Cist^®) in the prophylaxis of recurrent uncomplicated UTIs in premenopausal women.

METHODS

This single-centre study enrolled premenopausal women aged 18-50 years with an acute UTI and a history of recurrent uncomplicated UTIs. Patients were first treated with fosfomycin (3 g once a day for 2 days) to eliminate any underlying infection, followed by treatment with Lactoflorene Cist^® once a day for 10 days/month for 90 days (Group 1), Lactoflorene Cist^® once daily for 90 days (Group 2) or no treatment (Group 3; control). The main study endpoint was the rate of UTI recurrence during the study period. Any adverse events with treatment were also recorded.

RESULTS

A total of 55 women (mean age 39.3 years; range: 20-46) were enrolled in the study. A significantly higher proportion of patients in the control group experienced UTIs during the study period compared with the two treatment groups (52.9% vs 16.0% in Group 1 and 15.5% in group 2; p < 0.01). Similarly, a higher proportion of patients in Group 1 (65.8%) and Group 2 (68.7%) remained UTI-free during the study versus the control group. No adverse events were reported in the treated patients.

CONCLUSION

Prophylactic treatment with Lactoflorene Cist^® was effective and safe in the management of recurrent uncomplicated UTIs in premenopausal women.

Gardnerella and vaginal health: the truth is out there

The human vagina is a dynamic ecosystem in which homeostasis depends on mutually beneficial interactions between the host and their microorganisms. However, the vaginal ecosystem can be thrown off balance by a wide variety of factors. Bacterial vaginosis (BV) is the most common vaginal infection in women of childbearing age but its etiology is not yet fully understood, with different controversial theories being raised over the years. What is generally accepted is that BV is often characterized by a shift in the composition of the normal vaginal microbiota, from a Lactobacillus species dominated microbiota to a mixture of anaerobic and facultative anaerobic bacteria. During BV, a polymicrobial biofilm develops in the vaginal microenvironment, being mainly composed of Gardnerella species. The interactions between vaginal microorganisms are thought to play a pivotal role in the shift from health to disease and might also increase the risk of sexually transmitted infections acquisition. Here, we review the current knowledge regarding the specific interactions that occur in the vaginal niche and discuss mechanisms by which these interactions might be mediated. Furthermore, we discuss the importance of novel strategies to fight chronic vaginal infections.

Anti-Biofilm Properties of Saccharomyces cerevisiae CNCM I-3856 and Lacticaseibacillus rhamnosus ATCC 53103 Probiotics against G. vaginalis

Bacterial vaginosis (BV) is characterized by the presence of a polymicrobial biofilm where Gardnerella vaginalis plays a key role. Previously, we demonstrated that Saccharomyces cerevisiae CNCM (French National Collection of Cultures of Microorganisms) I-3856 is helpful in resolving experimental simulated BV in mice. In this study, we analyzed its capacity to affect G. vaginalis biofilms and to potentiate the activity of standard antimicrobial agents. We also investigated the anti-biofilm activity of Lacticaseibacillus rhamnosus GG (ATCC 53103), a well-known strain for its intestinal healthy benefits. Biofilm biomass was assessed by crystal violet staining, and G. vaginalis viability was assessed by a colony forming unit (CFU) assay. Here, for the first time, we demonstrated that S. cerevisiae CNCM I-3856 as well as L. rhamnosus GG were able (i) to significantly inhibit G. vaginalis biofilm formation, (ii) to markedly reduce G. vaginalis viability among the biomass constituting the biofilm, (iii) to induce disaggregation of preformed biofilm, and (iv) to kill a consistent amount of bacterial cells in a G. vaginalis preformed biofilm. Furthermore, S. cerevisiae CNCM I-3856 strongly potentiates the metronidazole effect on G. vaginalis biofilm viability. These results suggest that S. cerevisiae CNCM I-3856 as well as L. rhamnosus GG could be potential novel therapeutic agents against bacterial vaginosis.

Effects of Intravesical Lactobacillus Rhamnosus GG on Urinary Symptom Burden in People with Neurogenic Lower Urinary Tract Dysfunction

OBJECTIVE

To test the effectiveness of intravesical Lactobacillus rhamnosus GG (LGG) to reduce the burden of urinary symptoms for individuals with spinal cord injury and disease (SCI/D) with neurogenic lower urinary tract dysfunction (NLUTD) who manage their bladders with intermittent catheterization (IC).

DESIGN

A three-phase study (6 months each in baseline, intervention, and washout). Participants self-managed following the Self-Management Protocol using Probiotics (SMP-Pro), completing the online Urinary Symptom Questionnaire for Neurogenic Bladder-IC version (USQNB-IC) weekly.

SETTING

Nationwide (United States).

PARTICIPANTS

Ninety-six adults and seven children with SCI/D.

INTERVENTIONS

In response to one or both of the SMP-Pro trigger urinary symptoms, "cloudier" or "foul smelling" urine, participants self-administered using a clean urinary catheter an LGG+ Normal Saline instillate once or twice in a 30-hour period.

MAIN OUTCOME MEASURES

Change in USQNB-IC burden was adjusted individually according to the previous phase for four symptom types. Adjusted changes in burden between the intervention and washout phases were analyzed using one-sample t-tests. Holm correction was applied for the four types of symptoms: A, clinically actionable; B1, bladder function; B2, urine quality; and C, other.

RESULTS

During the intervention phase, participants met SMP-Pro instillation criteria 3.83 times on average (range 1-20). An average of 5.6 doses of LGG were instilled. For those who instilled at least once, burdens of type A and B2 symptoms were significantly improved at washout (both adjusted P < .05).

CONCLUSIONS

Self-instilled LGG seemed to improve "clinically actionable" (A) and "urine quality" (B2) symptom burden. No changes were observed for those who did not instill. This first-in-human clinical trial supports ongoing research of intravesical LGG, and the SMP-Pro for urinary symptoms.

Research of the potential biomarkers in vaginal microbiome for persistent high-risk human papillomavirus infection

Background

Vaginal dysbiosis may paly role in increased risk of human papillomavirus (HPV) infection. This study aims to explore potential vaginal microbiome biomarkers, to predict persistent high-risk HPV (HR-HPV) infection and cervical intraepithelial neoplasia (CIN) 2+, and to find novel treatment targets for HPV infection.

Methods

A total of 329 women aged 20-69 were enrolled in this study, including 59 with cervical persistent HPV infection irrespective of cytology status (group A), 139 with incident HPV infection (group B), and 131 without HPV infection (group C). Vaginal microbiome composition was determined by sequencing of barcoded 16S rDNA gene fragments (V4) on Illumina HiSeq2500.

Results

In genus level, the relative abundance of Prevotella, Porphyromonas and Enterococcus were significantly the highest in group A, while Bacteroides was the lowest in group A. In species level, we found the relative abundance of Prevotella bivia, Enterococcus durans and Porphyromonas uenonis were the highest in group A while Lactobacillus iners was significantly under-represented in group A than the other two, and Prevotella disiens was over-represented in group C than the other two groups.

Conclusions

A predominance of Prevotella bivia, Enterococcus durans and Porphyromonas uenonis with a concomitant paucity of Lactobacillus iners and Prevotella disiens may relate to HPV persistent infection. Furthermore, the relative abundance of Prevotella bivia being over 0.05554% with Prevotella disiens being under 0.02196% may be a good predictor for appearance CIN2+ for those diagnosed with the other 12 types of HR-HPV persistent infection but normal ThinPrep cytology test (TCT) testing. The exact molecular mechanism of the vaginal microbiome in the course of persistent HR-HPV infection and cervical neoplasia should be further explored. Future research should include intervention of vaginal microbiome composition to reverse the course of HR-HPV infection and the natural history of cervical neoplasia.

Mechanistic insights into the action of probiotics against bacterial vaginosis and its mediated preterm birth: An overview

The human body is a reservoir of numerous micro-creatures; whose role is substantial and indispensable in the overall development of human beings. The advances in omic approaches have offered powerful means to decipher the core microbiome and metabolome diversities in a specific organ system. The establishment of lactobacilli in the female reproductive tract is thought to be a paramount prerequisite that maintains homeostatic conditions for a sustainable and healthy pregnancy. Nevertheless, a plethora of such Lactobacillus strains of vaginal source revealed probiotic phenotypes. The plummeting in the occurrence of lactobacilli in the vaginal ecosystem is associated with several adverse pregnancy outcomes (APOs). One such pathological condition is "Bacterial Vaginosis" (BV), a pathogen dominated gynecological threat. In this scenario, the ascending traffic of notorious Gram-negative/variable BV pathogens to the uterus is one of the proposed pathways that give rise to inflammation-related APOs like preterm birth. Since antibiotic resistance is aggravating among urogenital pathogens, the probiotics intervention remains one of the alternative biotherapeutic strategies to overcome BV and its associated APOs. Perhaps, the increased inclination towards the safer and natural biotherapeutic strategies rather than pharmaceutical drugs for maintaining gestational and reproductive health resulted in the use of probiotics in pregnancy diets. In this context, the current review is an attempt to highlight the microbiome and metabolites signatures of BV and non-BV vaginal ecosystem, inflammation or infection-related preterm birth, host-microbial interactions, role and effectiveness of probiotics to fight against aforesaid diseased conditions.

The Need to Focus on Therapy Instead of Associations

Molecular analyses of the vaginal microbiota have uncovered a vast array of organisms in this niche, but not so far changed what has been known for a long time: lactobacilli are dominant in health, and the diagnosis and treatment of symptomatic bacterial vaginosis is sub-optimal, and has not changed for over 40 years. While the lowering cost of DNA sequencing has attracted more researchers to the field, and bioinformatics, and statistical tools have made it possible to produce large datasets, it is functional and actionable studies that are more urgently needed, not more microbial abundance, and health or disease-associative data. The triggers of dysbiosis remain to be identified, but ultimately treatment will require disrupting biofilms of primarily anaerobic bacteria and replacing them with the host's own lactobacilli, or health-promoting organisms. The options of using probiotic strains to displace the biofilms and for prebiotics to encourage resurgence of the indigenous lactobacilli hold great promise, but more researchers need to develop, and test these concepts in humans. The enormity of the problem of vaginal dysbiosis cannot be understated. It should not take another 40 years to offer better management options.

Patients With LR-HPV Infection Have a Distinct Vaginal Microbiota in Comparison With Healthy Controls

Condyloma acuminatum (CA) is a benign epithelium hyperplasia mainly caused by human papillomavirus (HPV), which is now the second most common viral sexually transmitted infection (STI) in China. In total, 90% of CA patients are caused by the low-risk HPV 6 and 11. Aside from low-risk HPV infection there are likely other factors within the local microenvironment that contribute to CA and there has been related research before. In this study, 62 vaginal specimens were analyzed using 16S rRNA gene sequencing. The diversity of the vaginal microbiota was higher and the composition was different with LR-HPV infection. While the relative abundance of dominant Firmicutes was lower, Actinobacteria, Proteobacteria, and Fusobacteria phyla were significantly higher; at the genus level Gardnerella, Bifidobacterium, Sneathia, Hydrogenophilus, Burkholderia, and Atopobium were higher. This study firstly confirmed a more accurate and comprehensive understanding of the relationship between low-risk HPV infection and vaginal microbiota, in order to provide a theoretical basis for further research on the occurrence and development of CA.

An update on the role of Atopobium vaginae in bacterial vaginosis: what to consider when choosing a treatment? A mini review

INTRODUCTION

Bacterial vaginosis (BV) is the most common vaginal disorder in reproductive-age women. The condition is characterised by the replacement of a healthy, lactobacilli-dominated vaginal microbiota by anaerobic and facultative anaerobic bacteria. BV increases the risk of acquisition of STIs and is associated with pregnancy complications. Although the composition of the bacteria in BV varies between individuals, there are some species such as Gardnerella, Atopobium, Mycoplasma, Snethia, Megasphera, Dialister, etc., that are found most frequently.

MATERIAL AND METHODS

Literature research to the importance of Atopobium vaginae in BV and treatment options.

RESULTS

Atopobium (A.) vaginae is an important component of the complex abnormal vaginal flora in BV; even though A. vaginae, like Gardnerella vaginalis, has also been detected in the normal flora, it is much more common in BV patients. A. vaginae has been shown to play an important role in the pathophysiology of BV and is thought to be at least a partial cause of the known negative sequelae. The presence of A. vaginae in the BV-associated biofilms and its resistance to some antimicrobial substances has been described - this seems to have a major impact on treatment outcome.

CONCLUSION

Current scientific data demonstrate that dequalinium chloride (Fluomycin®) is one of the valid therapeutic options for BV treatment, since it displays a broad antimicrobial spectrum against relevant vaginal pathogens, especially against G. vaginalis and A. vaginae, without having safety concerns.

Perceived stress and incident sexually transmitted infections in a prospective cohort

PURPOSE

Psychosocial stress has been associated with susceptibility to many infectious pathogens. We evaluated the association between perceived stress and incident sexually transmitted infections (STIs; Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis genital infections) in a prospective study of women. Stress may increase vulnerability to STIs by suppressing immune function and altering the protective vaginal microbiota.

METHODS

Using the 1999 Longitudinal Study of Vaginal Flora (n = 2439), a primarily African American cohort of women, we fitted Cox proportional hazards models to examine the association between perceived stress and incident STIs. We tested bacterial vaginosis (measured by Nugent Score) and sexual behaviors (condom use, number of partners, and partner concurrence) as mediators using VanderWeele's difference method.

RESULTS

Baseline perceived stress was associated with incident STIs both before and after adjusting for confounders (adjusted hazard ratio = 1.015; 95% confidence interval, 1.005-1.026). Nugent score and sexual behaviors significantly mediated 21% and 65% of this adjusted association, respectively, and 78% when included together in the adjusted model.

CONCLUSIONS

This study advances understanding of the relationship between perceived stress and STIs and identifies high-risk sexual behaviors and development of bacterial vaginosis-both known risk factors for STIs-as mechanisms underlying this association.

Engineering Lactobacillus rhamnosus GG and GR-1 to express HIV-inhibiting griffithsin

Probiotic bacteria are being explored for the in situ delivery of various therapeutic agents. In this study, we aimed to express two HIV-inhibiting lectins, actinohivin (AH) and griffithsin (GRFT), in the probiotic strains Lactobacillus rhamnosus GG and L. rhamnosus GR-1 for gastrointestinal and vaginal mucosal delivery, respectively. Constructs were generated for the intracellular and extracellular production of AH and GRFT under the control of the promoter of their Major Secreted Protein Msp1. Also, intracellular expression of GRFT was investigated under the control of the nisA promoter from the inducible nisin-controlled expression (NICE) system. For the extracellular localization, the signal leader peptide of Msp1/p75 from L. rhamnosus GG was translationally fused with the genes encoding AH and GRFT. Construction of recombinant strains expressing the AH monomer and dimer was unsuccessful, probably due to the intracellular toxicity of AH for the lactobacilli. On the other hand, recombinant strains for intra- and extracellular production of GRFT by L. rhamnosus GG and GR-1 were successfully constructed. The highest expression levels of recombinant GRFT were observed for the constructs under the control of the inducible nisA promoter and we demonstrated anti-HIV activity against an M-tropic and a T-tropic HIV-1 strain. We can conclude that recombinant Lactobacillus expressing anti-HIV lectins could contribute to the development of enhanced probiotic strains that are able to inhibit HIV transmission and subsequent replication, although further research and development are required.

Comparative Genomic and Phenotypic Analysis of the Vaginal Probiotic Lactobacillus rhamnosus GR-1

Lactobacillus represents a versatile bacterial genus, which can adapt to a wide variety of ecological niches, including human body sites such as the intestinal and urogenital tract. In this study, the complete genome sequence of the vaginal probiotic Lactobacillus rhamnosus GR-1 was determined and compared to other L. rhamnosus strains at genomic and phenotypic level. The strain GR-1 was originally isolated from a female urethra, and was assessed with L. rhamnosus GG from a feces sample of a healthy male, and L. rhamnosus LC705 from a dairy product. A key difference is the absence in GR-1 and LC705 of the spaCBA locus required for pili-mediated intestinal epithelial adhesion. In addition, the L. rhamnosus GR-1 genome contains a unique cluster for exopolysaccharide production, which is postulated to synthesize glucose-rich, rhamnose-lacking exopolysaccharide molecules that are different from the galactose-rich extracellular polysaccharide of L. rhamnosus GG. Compared to L. rhamnosus GG, L. rhamnosus GR-1 was also genetically predicted and experimentally shown to better metabolize lactose and maltose, and to better withstand oxidative stress, which is of relevance in the vagina. This study could thus provide a molecular framework for the selection of the optimal probiotic strain for each targeted niche and condition, but further substantiation of niche adaptation mechanisms of lactobacilli is warranted.

Antitumor mechanisms of bifidobacteria

Cancer remains one of the most common causes of mortality globally. Chemotherapy, one of the major treatment strategies for cancer, primarily functions by targeting the cancer cells and affecting them physiologically, but also affects normal cells, which is a major concern at present. Therefore, adverse effects of chemotherapy drugs, including myelosuppression and liver and kidney damage, are of concern. Now, microbial products have attracted attention in cancer treatment research. Notably, carcinogenesis is considered to be associated with microbial dysbiosis, particularly the positive antitumor effects of bifidobacteria. Although there remains a substantial amount to be understood about the regulation of bifidobacteria, bifidobacteria remain an attractive and novel source of cancer therapeutics. The present review focuses on introducing the latest information on the antitumor effects of bifidobacteria and to propose future strategies for using bifidobacteria in the development of cancer therapeutics.

Role of Lactobacillus reuteri in Human Health and Diseases

Lactobacillus reuteri (L. reuteri) is a well-studied probiotic bacterium that can colonize a large number of mammals. In humans, L. reuteri is found in different body sites, including the gastrointestinal tract, urinary tract, skin, and breast milk. The abundance of L. reuteri varies among different individuals. Several beneficial effects of L. reuteri have been noted. First, L. reuteri can produce antimicrobial molecules, such as organic acids, ethanol, and reuterin. Due to its antimicrobial activity, L. reuteri is able to inhibit the colonization of pathogenic microbes and remodel the commensal microbiota composition in the host. Second, L. reuteri can benefit the host immune system. For instance, some L. reuteri strains can reduce the production of pro-inflammatory cytokines while promoting regulatory T cell development and function. Third, bearing the ability to strengthen the intestinal barrier, the colonization of L. reuteri may decrease the microbial translocation from the gut lumen to the tissues. Microbial translocation across the intestinal epithelium has been hypothesized as an initiator of inflammation. Therefore, inflammatory diseases, including those located in the gut as well as in remote tissues, may be ameliorated by increasing the colonization of L. reuteri. Notably, the decrease in the abundance of L. reuteri in humans in the past decades is correlated with an increase in the incidences of inflammatory diseases over the same period of time. Direct supplementation or prebiotic modulation of L. reuteri may be an attractive preventive and/or therapeutic avenue against inflammatory diseases.

Has knowledge of the vaginal microbiome altered approaches to health and disease?

Sixteen years ago, when we published the first molecular characterization of the vaginal microbiota, little did we know the vast numbers of species that would be detected in this niche. As exciting as these discoveries have been, what have they and more recent advances contributed to how vaginal health and disease are managed? This review provides a brief discussion of the potential, but so far limited, applications that have arisen from microbiome research. Calls for innovation have been made before but to little avail.

The Role of the Genitourinary Microbiome in Pediatric Urology: a Review

PURPOSE OF REVIEW

In this review, we highlight the effects of the microbiome on urologic diseases that affect the pediatric patient.

RECENT FINDINGS

Perturbations in the urinary microbiome have been shown to be associated with a number of urologic diseases affecting children, namely urinary tract infection, overactive bladder/urge urinary incontinence, and urolithiasis. Recently, improved cultivation and sequencing technologies have allowed for the discovery of a significant and diverse microbiome in the bladder, previously assumed to be sterile. Early studies aimed to identify the resident bacterial species and demonstrate the efficacy of sequencing and enhanced quantitative urine culture. More recently, research has sought to elucidate the association between the microbiome and urologic disease, as well as to demonstrate effects of manipulation of the microbiome on various urologic pathologies. With an improved appreciation for the impact of the urinary microbiome on urologic disease, researchers have begun to explore the impact of these resident bacteria in pediatric urology.

Strain-specific inhibition of the adherence of uropathogenic bacteria to bladder cells by probiotic Lactobacillus spp

Urinary tract infections (UTIs), one of most common infections worldwide, face high recurrence rates and increasing antimicrobial resistance. Probiotic bacteria, especially of the genus Lactobacillus, are considered a promising preventive and/or treatment therapy against UTIs. In order to elucidate the mechanisms involved in these beneficial effects, we studied the impact of different Lactobacillus strains (Lactobacillus salivarius UCM572, L. plantarum CLC17 and L. acidophilus 01) in the adherence of reference and clinical uropathogenic strains (Escherichia coli ATCC® 53503, E. coli 10791, Enterococcus faecalis 04-1, En. faecalis 08-1 and Staphylococcus epidermidis 08-3) to T24 epithelial bladder cells. In general, the Lactobacillus strains with previous in vivo evidence of beneficial effects against UTIs (L. salivarius UCM572 and L. acidophilus 01) significantly inhibited the adherence of the five uropathogens to T24 cells, displaying percentages of inhibition ranging between 22.2% and 43.9%, and between 16.5% and 53.7%, respectively. On the other hand, L. plantarum CLC17, a strain with no expected effects on UTIs, showed almost negligible anti-adherence effects.Therefore, these in vitro results suggest that inhibition of the adherence of uropathogens to epithelial bladder cells may be one of the mechanisms involved in the potential beneficial effects of probiotics against UTIs in vivo.

Opposing effect of Lactobacillus on in vitro Klebsiella pneumoniae in biofilm and in an in vivo intestinal colonisation model

Beneficial bacteria represent potential sources of therapy, particularly in the battle against antibiotic-resistant pathogens. The Gram-negative bacillus Klebsiella pneumoniae is not only a paradigm of multi-resistant opportunistic pathogen, but it is also able to colonise the human intestine and displays a high capacity to form biofilm. In this study, the anti-biofilm activity of 140 neutralised Lactobacillus supernatants was assessed against K. pneumoniae. Among the 13 strains whose supernatant significantly impaired biofilm formation, Lactobacillus plantarum CIRM653 was selected because it was also able to impair K. pneumoniae preformed biofilm, independently of a bactericidal effect. Mixed K. pneumoniae/L. plantarum CIRM653 biofilms had reduced tridimensional structures associated with a significant decrease in K. pneumoniae biomass. Further investigation showed that L. plantarum CIRM653 supernatant induced transcriptional modifications of K. pneumoniae biofilm-related genes, including down-regulation of the quorum sensing-related lsr operons and over-expression of type 3 pili structure genes. Increased production of type 3 pili was validated by Western-blot, hemagglutination and adhesion assays. L. plantarum CIRM653 activity against K. pneumoniae was also assessed in a murine intestinal colonisation model: a constant faecal pathogen burden was observed, as against a gradual decrease in the control group. These results reveal that an in vitro a priori attracting anti-biofilm activity of Lactobacillus might be counterbalanced by an in vivo behaviour in a complex microbiota environment with potential deleterious dispersal of highly adherent K. pneumoniae cells, raising the question of the accuracy of in vitro assays in screening of beneficial microbes.

Effects of metronidazole combined probiotics over metronidazole alone for the treatment of bacterial vaginosis: a meta-analysis of randomized clinical trials

OBJECT

To evaluate the curative effect of metronidazole combined probiotics over metronidazole alone in the treatment of BV.

METHODS

We are searching randomized controlled trials on major online databases including PubMed, Science Direct, and Cochrane Database between 1990 and 2015. The primary outcome measure was the cure rate of BV. Cochran's Chi-square test (Q test) was used to test for heterogeneity among trials, and the I ² index. We used mixed-effects modeling for parameters of the summary hazard ratios (HRs), odds ratios (ORs), and their 95% confidence intervals (CIs).

RESULTS

Analysis suggests the cure rate of BV [RR = 1.12, 95% CI (0.94-1.32), p = 0.20], and the I ² index was 83%. The value of I ² index decreased to 16% after removing the study of Anukam et al., and Amsel 1.04 (95% CI 0.96-1.13) (p = 0.35), Nugent 1.02 (95% CI 0.94-1.11), short-term 1.01 (95% CI 0.93-1.10) (p = 0.79), long-term 1.06 (95% CI 0.98-1.14) (p = 0.13), Europe 1.06 (95% CI 0.95-1.19) (p = 0.32), Non-Europe 0.99 (95% CI 0.94-1.05) (p = 0.83). When the two same groups data were combined, respectively, the RRs for all studies were the same as 1.03 (95% CI 0.96-1.09) (p = 0.42) showing that there is not statistically significant in relevant stratums.

CONCLUSION

The result has showed an overall little significance for the efficacy of metronidazole combined probiotics over metronidazole alone for the treatment of BV. We need more further studies to provide enough evidence to confirm the benefits of probiotics in the treatment of BV.

The development of probiotics for women’s health

The idea you could use lactic acid bacteria to treat and prevent recurrence of vaginal infections was ridiculed in the early 1980s. Bacteria were the bad guys to be eradicated by current and emerging antibiotic classes. Thirty years later, probiotic administration of microbes is widespread worldwide, including for vaginal and bladder health in women, and the scientific basis and clinical efficacy data for this and multiple other applications prove the viability of this concept. The development of this approach, the creation of a definition for probiotics, and the expansion to other areas of women’s health form the basis of this review.

Etiology of bacterial vaginosis and polymicrobial biofilm formation

Microorganisms in nature rarely exist in a planktonic form, but in the form of biofilms. Biofilms have been identified as the cause of many chronic and persistent infections and have been implicated in the etiology of bacterial vaginosis (BV). Bacterial vaginosis is the most common form of vaginal infection in women of reproductive age. Similar to other biofilm infections, BV biofilms protect the BV-related bacteria against antibiotics and cause recurrent BV. In this review, an overview of BV-related bacteria, conceptual models and the stages involved in the polymicrobial BV biofilm formation will be discussed.

Bacterial biofilms in the vagina

A bacterial biofilm is a structured community of bacteria in a self-produced extracellular matrix, adherent to an inert surface or biological tissue. The involvement of biofilm in a bacterial infection implies that the infection is difficult to treat and that the patient will probably experience relapses of the condition. In bacterial vaginosis (BV), the lactobacilli concentration decreases, while the bacterial load of other (facultative) anaerobic bacteria increases. A hallmark of BV is the presence of clue cells, now known as the result of a polymicrobial biofilm formed in vaginal epithelial cells. Current knowledge of the individual roles of bacterial species involved in polymicrobial BV biofilms or interactions between these species are not fully known. In addition, knowledge of the composition matrix and triggers of biofilm formation is still lacking. Bacteria are able to attach to the surface of indwelling medical devices and cover these surfaces with biofilm. Vaginally inserted devices, such as tampons, intra-uterine devices and vaginal rings, can also be colonized by bacteria and be subjected to biofilm formation. This might hamper release of active product in case of drug-releasing devices such as vaginal rings, or promote the presence of unfavorable bacteria in the vagina. This paper reviews current knowledge of biofilms in the vaginal environment.

Does the vaginal microbiota play a role in the development of cervical cancer?

Persistent infection with oncogenic human papillomavirus (HPV) is necessary but not sufficient for the development of cervical cancer. The factors promoting persistence as well those triggering carcinogenetic pathways are incompletely understood. Rapidly evolving evidence indicates that the vaginal microbiome (VM) may play a functional role (both protective and harmful) in the acquisition and persistence of HPV, and subsequent development of cervical cancer. The first studies examining the VM and the presence of an HPV infection using next-generation sequencing techniques identified higher microbial diversity in HPV-positive as opposed to HPV-negative women. Furthermore, there appears to be a temporal relationship between the VM and HPV infection in that specific community state types may be correlated with a higher chance of progression or regression of the infection. Studies describing the VM in women with preinvasive disease (squamous intraepithelial neoplasia [SIL]) consistently demonstrate a dysbiosis in women with the more severe disease. Although it is plausible that the composition of the VM may influence the host's innate immune response, susceptibility to infection, and the development of cervical disease, the studies to date do not prove causality. Future studies should explore the causal link between the VM and the clinical outcome in longitudinal samples from existing biobanks.