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The Journal of Infectious Diseases Sep 2019Bacterial vaginosis (BV) is the most common cause of vaginal discharge. It is associated with an increased risk of preterm delivery, pelvic inflammatory disease, and an... (Review)
Review
Bacterial vaginosis (BV) is the most common cause of vaginal discharge. It is associated with an increased risk of preterm delivery, pelvic inflammatory disease, and an increased risk of acquisition of sexually transmitted infections including human immunodeficiency virus (HIV). The epidemiology of BV supports sexual transmission. However, its etiology remains unknown. At the center of the debate is whether BV is caused by a primary pathogen or a polymicrobial consortium of microorganisms that are sexually transmitted. We previously published a conceptual model hypothesizing that BV is initiated by sexual transmission of Gardnerella vaginalis. Critics of this model have iterated that G. vaginalis is found in virginal women and in sexually active women with a normal vaginal microbiota. In addition, colonization does not always lead to BV. However, recent advances in BV pathogenesis research have determined the existence of 13 different species within the genus Gardnerella. It may be that healthy women are colonized by nonpathogenic Gardnerella species, whereas virulent strains are involved in BV development. Based on our results from a recent prospective study, in addition to an extensive literature review, we present an updated conceptual model for the pathogenesis of BV that centers on the roles of virulent strains of G. vaginalis, as well as Prevotella bivia and Atopobium vaginae.
Topics: Actinobacteria; Female; Gardnerella vaginalis; Humans; Models, Biological; Prevotella; Vagina; Vaginosis, Bacterial; Virulence
PubMed: 31369673
DOI: 10.1093/infdis/jiz342 -
Revista Internacional de Andrologia Mar 2024It is estimated that microorganisms colonize 90% of the body surface. In some tracts, such as the genitourinary tract, the microbiota varies throughout life, influenced...
It is estimated that microorganisms colonize 90% of the body surface. In some tracts, such as the genitourinary tract, the microbiota varies throughout life, influenced by hormonal stimulation and sexual practices. This study evaluated the semen differences and presence of , , and in semen samples from patients with symptoms of chronic prostatitis and men asymptomatic for urogenital infections. Fifty-three semen samples were included: 22 samples from men with symptoms of chronic prostatitis and 31 asymptomatic men (control group). In addition to the presence of , , and , semen parameters, total antioxidant capacity of seminal plasma, prostatic antigen and some proinflammatory cytokines were evaluated in each semen sample. Volunteers with symptoms of chronic prostatitis presented a lower percentage of sperm morphology (4.3% control group 6.0%, = 0.004); in the semen samples of volunteers in the group asymptomatic for urogenital infections, microorganisms associated with the vaginal microbiota were detected more frequently. The presence of bacteria in the vaginal microbiota can also benefit male reproductive health, which undergoes various modifications related to lifestyle habits that are susceptible to modification. Microorganisms associated with the vaginal microbiota, such as , , and , may have a protective role against the development of male genitourinary diseases such as prostatitis.
Topics: Humans; Male; Prostatitis; Semen; Adult; Microbiota; Coitus; Gardnerella vaginalis; Lactobacillus; Vagina; Middle Aged; Actinobacteria; Female; Young Adult; Chronic Disease; Case-Control Studies; Semen Analysis; Cytokines
PubMed: 38735876
DOI: 10.22514/j.androl.2024.006 -
MSphere Jun 2022Bacterial vaginosis (BV) is a dysbiosis of the vaginal microbiome, characterized by low levels of lactobacilli and overgrowth of a diverse group of bacteria, associated...
Bacterial vaginosis (BV) is a dysbiosis of the vaginal microbiome, characterized by low levels of lactobacilli and overgrowth of a diverse group of bacteria, associated with higher risk of a variety of infections, surgical complications, cancer, and preterm birth (PTB). Despite the lack of a consistently applicable etiology, spp. are often associated with both BV and PTB, and has known symbiotic relationships with both Peptostreptococcus anaerobius and Gardnerella vaginalis. Higher risk of PTB can also be predicted by a composite of metabolites linked to bacterial metabolism, but their specific bacterial source remains poorly understood. Here, we characterize diversity of metabolic strategies among BV-associated bacteria and lactobacilli and the symbiotic metabolic relationships between and its partners and show how these influence the availability of metabolites associated with BV/PTB and/or pro- or anti-inflammatory immune responses. We confirm a commensal relationship between and , refining its mechanism, which sustains a substantial increase in acetate production. In contrast, the relationship between and strains, with sequence variant G2, is mutualistic, with outcome dependent on the metabolic strategy of the strain. Taken together, our data show how knowledge of inter- and intraspecies metabolic diversity and the effects of symbiosis may refine our understanding of the mechanism and approach to risk prediction in BV and/or PTB. Bacterial vaginosis (BV) is the most common vaginal infection for women of childbearing age. Although 50% of women with BV do not have any symptoms, it approximately doubles the risk of catching a sexually transmitted infection and also increases the risk of preterm delivery in pregnant women. Recent studies of the vaginal microbiota have suggested that variation between species in the same genus or between strains of the same species explain better or poorer outcomes or at least some coexistence patterns for bacteria of concern. We tested whether such variation is manifested in how vaginal bacteria grow in the laboratory and whether and how they may share nutrients. We then showed that this affected the overall cocktail of chemicals they produce, including bacterially derived chemicals that we have previously shown are linked to a higher risk of preterm delivery.
Topics: Bacteria; Female; Humans; Infant, Newborn; Lactobacillus; Magnetic Resonance Spectroscopy; Pregnancy; Premature Birth; Symbiosis; Vaginosis, Bacterial
PubMed: 35491843
DOI: 10.1128/msphere.00166-22 -
Clinical Nutrition (Edinburgh, Scotland) Mar 2022Malnutrition has been confirmed to play an important role in colorectal cancer (CRC) progression via the gut microenvironment. However, the characteristics of the gut...
BACKGROUD
Malnutrition has been confirmed to play an important role in colorectal cancer (CRC) progression via the gut microenvironment. However, the characteristics of the gut microbiota or its potential biological mechanism in CRC remain inconclusive.
METHODS
In this work, Patient-Generated Subjective Global Assessment (PG-SGA) tool and 16sRNA sequencing were prepared to detect the variation in gut microbiota and the association between nutrition status and gut microbiota. RDA/CCA analysis was used to evaluate the relationship between faecal microbiota from malnourished CRC and clinical nutrition indicators. To investigate the mechanism of the gut microbiota in CRC, faecal samples from malnourished CRC patients were transplanted into C57BL/6J and DSS/AOM mouse models. Moreover, FACS and IHC were prepared to detect the infiltration of B cells and macrophages. qPCR and Elisa assays were performed to explore the expression of cytokines.
RESULT
We found dramatic variation in the faecal microbiota among patients with different nutritional statuses, discovering that specific microbiota species, namely, Atopobium vaginae, Selenomonas sputigena and Faecalibacterium prausnitzii, may be considered diagnostic biomarkers in malnutrition and indicate poor prognosis. High expression level of A. vaginae in CRC tissues revealed the poorer overall survival compared with low expression level (Mean survival: 23.0 months vs 29.0 months). Faecal from malnourished colorectal cancer were found to be protumorigenic. More importantly, our evidence suggests that after faecal microbiota transplantation, B cells and macrophages are recruited to activate specific tumour immunity in CRC. Depletion of B cells significantly suppressed faecal microbiota-induced M2b polarization as well as the protumorigenic activity of tumour-associated macrophages in vivo.
CONCLUSION
Faecal microbiota in CRC under malnutrition conditions exhibits specific characteristics that accelerate CRC progression and regulate B cells and macrophages. The use of specific faecal microbial species could be a feasible approach for identifying the malnutrition status of patients and demonstrating the poor prognosis of CRC.
Topics: Animals; Colorectal Neoplasms; Feces; Gastrointestinal Microbiome; Humans; Malnutrition; Mice; Mice, Inbred C57BL; Tumor Microenvironment
PubMed: 35124471
DOI: 10.1016/j.clnu.2022.01.001 -
Danish Medical Journal Apr 2014Bacterial vaginosis (BV) is an imbalance of the vaginal bacterial microbiota and its aetiology is still unknown. Our aims were to investigate the diagnostic potential of... (Review)
Review
BACKGROUND
Bacterial vaginosis (BV) is an imbalance of the vaginal bacterial microbiota and its aetiology is still unknown. Our aims were to investigate the diagnostic potential of species/genus specific quantitative PCR (qPCR) for bacteria present in swabs and first-void urine (FVU) samples using Nugent's and Claeys' criteria and 454 sequencing of the vaginal microbiome as reference.
METHODS
Self-collected swabs, vaginal smears and FVU were obtained from 177 women from Greenland (Study I and III) and physician-collected vaginal swabs and smears were obtained from 163 Swedish women (Study II). BV was diagnosed by Nugent's criteria in Study I and III and by Amsel's criteria in Study II. The vaginal swabs and FVU samples were analysed by qPCR for selected vaginal bacteria in all three studies and for four sexually transmitted infections (STIs) in Study I.
RESULTS
Study I: STIs were common in women from Greenland and BV was found in 45% of these women but was not associated with individual STIs. In multivariate logistic analysis, Atopobium vaginae and Prevotella spp. were both independently associated with BV in swabs. BV could be subdivided into clusters dominated by a single or a few species together. Seven vaginal bacteria (A. vaginae, Prevotella spp. Gardnerella vaginalis, Bacterial vaginosis associated bacterium (BVAB) 2, Eggerthella-like bacterium, Leptotrichia amnionii and Megasphaera type 1) had areas under the receiver operating characteristic (ROC) curve > 85% in swabs, suggesting that they were good predictors of BV according to Nugent. Study II: For the majority of species/genera, the kappa values indicated fair to good agreement when their presence was determined by 454 pyrosequencing versus real-time PCR. The same seven vaginal bacteria as found in Study I, had areas under the ROC-curve > 85% in swabs from Swedish women, demonstrating a good diagnostic accuracy for BV according to Amsel. Study III: In a multivariate model, Megasphaera type 1 and Prevotella spp. remained significantly associated with BV in FVU samples. A linear regression analysis showed good agreement between bacterial load from swabs and FVU, but Prevotella spp. could be detected in high numbers in a few FVU samples without being present in swabs. After applying ROC curve analysis, the same seven vaginal bacteria as previously mentioned showed good prediction for BV according to Nugent in FVU. BV could be detected with comparable sensitivity in FVU and vaginal swabs.
CONCLUSION
BV can be diagnosed by molecular methods performed either on swabs or urine but it is important to apply thresholds in order to improve the accuracy of the diagnosis. Furthers it was possible to identify clusters of BV dominated by single or paired bacteria, and these clusters could classify BV into subgroups, providing a more detailed understanding of the condition. Seven vaginal bacteria were highly accurate for BV diagnosis both in swabs and FVU. Finally a good agreement between Nugent and Claeys was found.
Topics: Biofilms; DNA, Bacterial; Female; Gardnerella vaginalis; Humans; Immunity, Innate; Lactobacillus; Risk Factors; Vagina; Vaginal Smears; Vaginosis, Bacterial
PubMed: 24814599
DOI: No ID Found -
Microbes and Infection Apr 2008Bacterial vaginosis is the most common vaginal disorder among women of reproductive age. The pathogenesis of bacterial vaginosis is poorly understood, but is defined by...
Bacterial vaginosis is the most common vaginal disorder among women of reproductive age. The pathogenesis of bacterial vaginosis is poorly understood, but is defined by a transition in the vaginal flora from the predominant Lactobacillus species to other bacterial species such as Atopobium vaginae and Gardnerella vaginalis. This change is associated with an increase in vaginal cytokine secretion. We hypothesize that vaginal epithelial cells respond to bacterial vaginosis-associated bacteria by triggering an innate immune response. We observed that vaginal epithelial cells secreted interleukin-6 and interleukin-8 in response to Atopobium vaginae and Gardnerella vaginalis, but not to Lactobacillus crispatus. Atopobium vaginae induced increased levels of interleukin-6 and interleukin-8 transcripts, as well as increased transcripts for the antimicrobial peptide beta-defensin 4. This innate immune response required live bacteria capable of protein synthesis in direct contact with vaginal epithelial cells. The response of vaginal epithelial cells was mediated by Toll-like receptor 2, required the adaptor protein MyD88, and involved activation of the NFkappaB signaling pathway. These results suggest that Atopobium vaginae stimulates an innate immune response from vaginal epithelial cells, leading to localized cytokine and defensin production, and possibly contributes to the pathogenesis of bacterial vaginosis.
Topics: Actinobacteria; Cell Line; Epithelial Cells; Female; Gardnerella vaginalis; Gene Expression Profiling; Humans; Immunity, Innate; Interleukin-6; Interleukin-8; Lactobacillus; Myeloid Differentiation Factor 88; NF-kappa B; RNA, Messenger; Toll-Like Receptor 2; Vaginosis, Bacterial; beta-Defensins
PubMed: 18403235
DOI: 10.1016/j.micinf.2008.01.004 -
Frontiers in Cellular and Infection... 2020The aetiology of bacterial vaginosis (BV) is not well-understood, and prevalence appears to be higher among women living in sub-Saharan Africa. A recent conceptual model...
The aetiology of bacterial vaginosis (BV) is not well-understood, and prevalence appears to be higher among women living in sub-Saharan Africa. A recent conceptual model implicates three main bacteria ( and ), sexual activity, sialidase activity, and biofilm formation in the pathogenesis of BV. We describe the vaginal microbiota, presence of the putative sialidase A gene of , and biofilm among 386 adolescent girls aged 17 and 18 years in a cross-sectional study in Mwanza, Tanzania around the time of expected sexual debut. Vaginal swabs were collected and tested by quantitative polymerase chain reaction (qPCR) for five species, , the sialidase A gene of , and by fluorescence hybridisation (FISH) for evidence of and biofilm. We conducted a risk factor analysis of and , and explored the associations between biofilm, the presence of the sialidase A gene, and non-optimal vaginal microbiota (Nugent 4-7) and were detected in 69 and 82% of girls, respectively. The prevalence of was higher than previously reported in earlier studies among East and Southern African women. were independently associated with reported penile-vaginal sex. Samples with all three BV-associated bacteria made up the highest proportion of samples with Nugent-BV compared to samples with each bacterium alone or together in pairs. Of the 238 girls with , 63% had the sialidase A gene detected, though there was no difference by reported sexual activity ( = 0.197). Of the 191 girls with results for sialidase A gene and FISH, there was strong evidence for an increased presence of sialidase A gene among those with evidence of a biofilm ( < 0.001). There was a strong association between biofilm and non-optimal microbiota (aOR67.00; 95% CI 26.72-190.53). These results support several of the steps outlined in the conceptual model, although the role of sexual activity is less clear. We recommend longitudinal studies to better understand changes in vaginal microbiota and biofilm formation around the time of sexual debut.
Topics: Actinobacteria; Adolescent; Cross-Sectional Studies; Female; Humans; Microbiota; Prevotella; Sexual Behavior; Tanzania; Vagina
PubMed: 32670894
DOI: 10.3389/fcimb.2020.00305 -
American Journal of Obstetrics and... Jun 2018Data evaluating the impact of contraceptives on the vaginal microbiome are limited and inconsistent.
BACKGROUND
Data evaluating the impact of contraceptives on the vaginal microbiome are limited and inconsistent.
OBJECTIVE
We hypothesized that women initiating copper intrauterine device use would have increased bacterial vaginosis and bacterial vaginosis-associated microbes with use compared to women initiating and using hormonal contraceptive methods.
STUDY DESIGN
Vaginal swabs (N = 1047 from 266 participants seeking contraception) for Nugent score determination of bacterial vaginosis and quantitative polymerase chain reaction analyses for assessment of specific microbiota were collected from asymptomatic, healthy women aged 18-35 years in Harare, Zimbabwe, who were confirmed to be free of nonstudy hormones by mass spectrometry at each visit. Contraception was initiated with an injectable (depot medroxyprogesterone acetate [n = 41], norethisterone enanthate [n = 44], or medroxyprogesterone acetate and ethinyl estradiol [n = 40]), implant (levonorgestrel [n = 45] or etonogestrel [n = 48]), or copper intrauterine device (n = 48) and repeat vaginal swabs were collected after 30, 90, and 180 days of continuous use. Self-reported condom use was similar across all arms at baseline. Quantitative polymerase chain reaction was used to detect Lactobacillus crispatus, L jensenii, L gasseri/johnsonii group, L vaginalis, L iners, Gardnerella vaginalis, Atopobium vaginae, and Megasphaera-like bacterium phylotype I from swabs. Modified Poisson regression and mixed effects linear models were used to compare marginal prevalence and mean difference in quantity (expressed as gene copies/swab) prior to and during contraceptive use.
RESULTS
Bacterial vaginosis prevalence increased in women initiating copper intrauterine devices from 27% at baseline, 35% at 30 days, 40% at 90 days, and 49% at 180 days (P = .005 compared to marginal prevalence at enrollment). Women initiating hormonal methods had no change in bacterial vaginosis prevalence over 180 days. The mean increase in Nugent score was 1.2 (95% confidence interval, 0.5-2.0; P = .001) in women using copper intrauterine devices. Although the frequency and density of beneficial lactobacilli did not change among intrauterine device users over 6 months, there was an increase in the log concentration of G vaginalis (4.7, 5.2, 5.8, 5.9; P = .046) and A vaginae (3.0, 3.8, 4.6, 5.1; P = .002) between baseline and 30, 90, and 180 days after initiation. Among other contraceptive groups, women using depot medroxyprogesterone acetate had decreased L iners (mean decrease log concentration = 0.8; 95% confidence interval, 0.3-1.5; P = .004) and there were no significant changes in beneficial Lactobacillus species over 180 days regardless of contraceptive method used.
CONCLUSION
Copper intrauterine device use may increase colonization by bacterial vaginosis-associated microbiota, resulting in increased prevalence of bacterial vaginosis. Use of most hormonal contraception does not alter vaginal microbiota.
Topics: Adult; Contraceptive Agents, Female; DNA, Bacterial; Desogestrel; Drug Implants; Ethinyl Estradiol; Female; Gardnerella vaginalis; Humans; Intrauterine Devices, Copper; Lactobacillus crispatus; Lactobacillus gasseri; Levonorgestrel; Medroxyprogesterone Acetate; Megasphaera; Microbiota; Norethindrone; Polymerase Chain Reaction; Protective Factors; Risk Factors; Vagina; Vaginosis, Bacterial; Young Adult
PubMed: 29505773
DOI: 10.1016/j.ajog.2018.02.017 -
Frontiers in Microbiology 2015Bacterial vaginosis (BV) is the most common genital tract infection in women during their reproductive years and it has been associated with serious health... (Review)
Review
Bacterial vaginosis (BV) is the most common genital tract infection in women during their reproductive years and it has been associated with serious health complications, such as preterm delivery and acquisition or transmission of several sexually transmitted agents. BV is characterized by a reduction of beneficial lactobacilli and a significant increase in number of anaerobic bacteria, including Gardnerella vaginalis, Atopobium vaginae, Mobiluncus spp., Bacteroides spp. and Prevotella spp.. Being polymicrobial in nature, BV etiology remains unclear. However, it is certain that BV involves the presence of a thick vaginal multi-species biofilm, where G. vaginalis is the predominant species. Similar to what happens in many other biofilm-related infections, standard antibiotics, like metronidazole, are unable to fully eradicate the vaginal biofilm, which can explain the high recurrence rates of BV. Furthermore, antibiotic therapy can also cause a negative impact on the healthy vaginal microflora. These issues sparked the interest in developing alternative therapeutic strategies. This review provides a quick synopsis of the currently approved and available antibiotics for BV treatment while presenting an overview of novel strategies that are being explored for the treatment of this disorder, with special focus on natural compounds that are able to overcome biofilm-associated antibiotic resistance.
PubMed: 26834706
DOI: 10.3389/fmicb.2015.01528 -
Nutrients Jan 2023Bacterial vaginosis (BV) is the most common disease in women of childbearing age and is caused by the growth of abnormal microbiota in the vagina. Probiotic consumption... (Randomized Controlled Trial)
Randomized Controlled Trial
Bacterial vaginosis (BV) is the most common disease in women of childbearing age and is caused by the growth of abnormal microbiota in the vagina. Probiotic consumption can be an effective alternative treatment to preserve or improve vaginal health. In the present study, MED-01, a complex of five strains of probiotic candidates isolated from the vagina of Korean women, was used. This study was designed as a 12-week, randomized, multicenter, double-blind, placebo-controlled clinical trial to evaluate the efficacy and safety of MED-01 on vaginal health. A total of 101 reproductive-aged women with a Nugent score of 4-6 took MED-01 (5.0 × 10 CFU) or a placebo once a day, and 76 participants completed the procedure. MED-01 significantly reduced the Nugent score compared with the placebo. Quantitative PCR analysis confirmed that was significantly increased in the vagina, whereas harmful bacteria such as spp., and were suppressed after 12 weeks of MED-01 ingestion. No adverse events to the test food supplements were observed in the participants. These results confirmed that MED-01 can be used as a probiotic for treating BV, as it improves the vaginal microbiota.
Topics: Female; Humans; Adult; Vagina; Vaginosis, Bacterial; Probiotics; Gardnerella vaginalis; Dietary Supplements
PubMed: 36678202
DOI: 10.3390/nu15020331