Healthy Vaginal Microbiota and Influence of Probiotics Across the Female Life Span

Factors associated with Nugent-bacterial vaginosis in pregnancy and postpartum among women in rural northwestern Bangladesh

Community-based longitudinal data on factors linked to bacterial vaginosis (BV) during and after pregnancy in Bangladesh are limited. Using data from a rural randomized trial of vitamin A and β-carotene supplementation, we examined factors associated with Nugent-score-assessed BV. Self-collected vaginal swabs from 1,812 participants were obtained in early pregnancy, late pregnancy, and 3 months postpartum for Nugent scoring. We analyzed associations between participant factors and Nugent-BV (scores 7-10 vs. 0-6; 4-10 vs. 0-3) at each time point. Bivariate associations were tested using chi-square and t-tests, and multivariable log-binomial regression was used to estimate adjusted prevalence ratios with 95% confidence intervals. In early pregnancy, consistent soap use during bathing (vs. never/sometimes) was associated with a decreased risk of Nugent-BV 7-10 (adjusted prevalence ratio (aPR): 0.64, 95% CI: 0.43, 0.96). In late pregnancy, Hindu religion (vs. Muslim) (aPR: 2.68, 95% CI: 1.52, 4.72) and higher gestational age (aPR: 1.18, 95% CI: 1.04, 1.35) were associated with increased risk of Nugent-BV 7-10 and 4-10. Furthermore, maternal underweight (BMI < 18.5 kg/m² vs. ≥ 18.5) (aPR: 0.62, 95% CI: 0.44, 0.87) and having ≥1 antenatal care visit (vs. none) (aPR: 0.59, 95% CI: 0.38, 0.91) were associated with reduced risk of Nugent-BV 4-10. Among multiparous individuals, a longer pregnancy interval of ≥18 months (vs. < 18 months) was protective against Nugent-BV 7-10 (aPR: 0.34, 95% CI: 0.14, 0.81). At 3-months postpartum, vitamin A supplementation (vs. placebo) was associated with a decreased risk of Nugent-BV 7-10, consistent with prior trial findings. Our findings indicate that Nugent-BV during pregnancy and postpartum is linked to modifiable factors, including hygiene, nutrition, birth spacing, and healthcare access. Rigorous randomized trials are needed to evaluate their ability to reduce BV, promote long-term vaginal health, and lower the risk of adverse pregnancy outcomes.

Vaginal mycobiome characteristics and therapeutic strategies in vulvovaginal candidiasis (VVC): differentiating pathogenic species and microecological features for stratified treatment

SUMMARYVulvovaginal candidiasis (VVC) is a prevalent global health burden, particularly among reproductive-aged women. Recurrent VVC affects a significant proportion of this population, presenting therapeutic challenges. The predominant pathogen, Candida albicans, opportunistically transitions from a commensal organism to a pathogen when microenvironmental conditions become dysregulated. Recently, non-albicans Candida species have gained attention for their reduced antifungal susceptibility and recurrence tendencies. Diagnosis is constrained by the limitations of conventional microbiological techniques, while emerging molecular assays offer enhanced pathogen detection yet lack established thresholds to differentiate between commensal and pathogenic states. Increasing resistance issues are encountered by traditional azole-based antifungals, necessitating innovative approaches that integrate microbiota modulation and precision medicine. Therefore, this review aims to systematically explore the pathogenic diversity, drug resistance mechanisms, and biofilm effects of Candida species. Vaginal microbiota (VMB) alterations associated with VVC were also examined, focusing on the interaction between Lactobacillus spp. and pathogenic fungi, emphasizing the role of microbial dysbiosis in disease progression. Finally, the potential therapeutic approaches for VVC were summarized, with a particular focus on the use of probiotics to modulate the VMB composition and restore a healthy microbial ecosystem as a promising treatment strategy. This review addresses antifungal resistance and adopts a microbiota-centric approach, proposing a comprehensive framework for personalized VVC management to reduce recurrence and improve patient outcomes.

A Comparative Longitudinal Study Analyzing Vaginal Microbiota Differences Between Term and Preterm Pregnancies in Korean Women

Background and Objectives: Preterm birth (PTB), defined as delivery before 37 weeks of gestation, remains a significant public health concern due to its association with neonatal morbidity and mortality. Although studies have suggested that microbial factors in vaginal microbiota (VMB) influence PTB, longitudinal research on Korean women is limited. This study aimed to analyze VMB differences between term and preterm pregnancies in Korean women and their correlation with the cervical length (CL). Materials and Methods: A cohort of 60 pregnant Korean women (40 who had a term birth (TB) and 20 who had a PTB) was recruited. Vaginal samples were collected at five time points (first, second, and third trimester; 1-2 weeks postpartum; 1-2 months postpartum). Microbial DNA was extracted and analyzed using quantitative PCR targeting 12 bacterial species. The CL was measured in the second and third trimesters. Results: Lactobacillus crispatus was consistently dominant in the TB group, whereas PTB cases exhibited greater microbial diversity with elevated levels of Prevotella salivae and Ureaplasma species. The CL was significantly shorter in PTB cases, correlating with shifts in the VMB composition. Conclusions: A stable, Lactobacillus-dominant microbiome is protective in pregnancy, while increased diversity in PTB cases suggests microbial biomarkers for early risk prediction. Combining VMB profiling with CL measurement may enhance early, non-invasive PTB risk assessments.

Roles of probiotics against HPV through the gut-vaginal axis

Human papillomavirus (HPV) is a sexually transmitted virus, whose persistent infection is the main reason for invasive cervical cancer (ICC), which is the fourth most common type of cancer in women, with more than 500 000 new cases every year. After infection, various alterations occur in the host, facilitating the virus's evasion of immune system clearance and promoting its proliferation. Oral probiotic consumption can influence the whole body's immunity, inflammatory reflection, neural, endocrine humoral, metabolic pathways and other organs by adjusting the components of gut microbiota (GM). Some evidence shows there is a tight connection between GM and vaginal microbiota (VM), which is referred to as the gut-vaginal axis. This review investigates the potential role of probiotics in clearing HPV via the gut-vagina axis, emphasizing the effectiveness of Lactobacillus in preventing vaginal diseases and suggesting its potential for HPV clearance. Understanding the role of probiotics in the gut-vagina axis could pave the way for new strategies to reduce and eliminate HPV and related diseases.

Probiotics and Synbiotics: Applications, Benefits, and Mechanisms for the Improvement of Human and Ecological Health

This review explores the multifaceted roles and applications of probiotics, emphasizing their significance in maintaining and enhancing host health through microbial interactions. It includes the concept of holobionts and the symbiotic relationships between hosts and their microbiomes, illustrating how various microbiota can enhance immunity, support growth, and prevent diseases. It delves into the customization of probiotics using molecular and genomic techniques, focusing Enterococcus, Bifidobacterium, and Lactobacillus species. Furthermore, it discusses the symbiotic effects of symbiotics which aids in enhancing the survivability and beneficial effects of probiotics. The role beneficial microbes in gut is emphasized, noting its impact on preventing diseases and maintaining a stable microbial community. The potential therapeutic value of probiotics includes the ability to treat gastrointestinal diseases, as well as to strengthen the immune system and reduce the number of free radicals that are present in the body. Additionally, it explores secondary metabolites produced by bacteria in the gut, such as bacteriocins and exopolysaccharides, and their effect on the health of human, particularly in the gastrointestinal tract. The review concludes by addressing the use of probiotics in traditional medicine and their potential in novel therapeutic applications, including the treatment of endangered wildlife species and various human ailments.

Differences in sexually transmitted infection-associated cervical infections in pelvic inflammatory disease patients between adolescents and adults

OBJECTIVE

Pelvic inflammatory disease (PID) is an infection of female reproductive organs mainly in sexually active patients, which can cause serious complications throughout life. We aimed to analyze the risk factors and differences in sexually transmitted infections (STIs) between adolescents and adult PID patients.

MATERIALS AND METHODS

We conducted a retrospective study based on descriptive and statistical analyses of the clinical records of patients with PID treated with antibiotics between January 2013 and December 2023 at Busan Paik Hospital. In this study, we analyzed the clinical characteristics of patients and the types of cultured bacteria in vaginal discharge, as well as their association with STIs according to age.

RESULTS

Three hundred patients required hospitalization and treatment with antibiotics. Thirty-nine (13.0 %) were adolescent patients, and 261 (87 %) were adult patients. Infections of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, and Trichomonas vaginalis were more prevalent in adolescents than in adult patients (P < 0.001, 0.001, 0.013, <0.001, 0.004 and 0.010, respectively). Although Lactobacillus spp. was predominant among the cultured strains in both adolescents and adults, it was detected in 29.6 % of adolescent patients and 48.4 % of adults; its detection rates were relatively lower among adolescents (P = 0.071). Among adolescents, 30.6 % were smokers, while 13.3 % were smokers among adult patients. Although there was a higher prevalence of smoking among adolescents, the statistical analysis did not show a significant difference in smoking prevalence between adolescents and adults (P = 0.08).

CONCLUSION

In this study, adolescents with PID exhibited a higher prevalence of STIs compared to adults. Additionally, One-third of these adolescents were smokers and did not use barrier protection. PID in adolescents has distinct risk factors, causative bacteria, and clinical features compared to adults. Hence, it is crucial to develop effective strategies for treating and preventing STIs in this population.

Refining Unfavorable Vaginal Microbial Community in Infertile Women Subjected to Precision Probiotic Intervention: An Exploratory Single-Arm, Prospective, Open-Label, Interventional Study

BACKGROUND AND AIMS

Vaginal microbiomes have been classified into five different general categories, termed Community State Type (CSTs), with CST-III and CST-IV often associated with vaginal dysbiosis which makes women more prone to recurrent infections and assisted reproductive technology (ART) failure. Since a healthy microbiome is one of the key steps for successful reproduction, we investigated the impact of modulating the vaginal microbiota through the oral administration of probiotic formula consisting of a consortium of vaginal-specific lactobacilli and prebiotics (Personal Flora 2®).

METHODS

We recruited 32 women who had previous failed IVF cycles and were scheduled to undergo ART. We examined the composition of the vaginal microbiota before and after oral probiotic supplementation using 16S ribosomal RNA (rRNA) sequencing technology.

RESULTS

Our data show a noticeable modulation of the vaginal microbiome upon probiotic supplementation. In particular, precision probiotic intervention lowers the species diversity, favoring the dominance of Lactobacillus (p = 0.015) and Bifidobacterium (p = 0.000) whilst decreasing the percentage of Atopobium (p = 0.003), Gardnerella (p = 0.022), and Prevotella (p = 0.000).

CONCLUSIONS

Although CST-III and CST-IV are generally considered detrimental, gynecologists should not refrain from performing IVF in these women if they have been previously subjected to a consortium of precision probiotics treatments, as the administration of specific probiotics reduces the presence of pathogenic bacteria promoting the increase in lactobacilli associated with a healthy vaginal ecosystem, which could impact pregnancy success.

Cervicovaginal Microbiome: Physiology, Age-Related Changes, and Protective Role Against Human Papillomavirus Infection

Background/Objectives: Persistent high-risk human papillomavirus (HPV) infections are the leading cause of cervical cancer. Developing evidence suggests that the cervicovaginal microbiome plays a significant role in modulating HPV persistence and progression to cervical neoplasia. This review synthesizes the current knowledge on the interplay between the cervicovaginal microbiome and local immunity in HPV infections, emphasizing microbial diversity, immune responses, and potential therapeutic implications. Methods: A thorough review of the literature was performed using Embase, PubMed, Scopus, and Google Scholar, encompassing studies published between 2000 and 2024. Studies examining the composition of the microbiome, immune responses, and HPV-related outcomes were evaluated and synthesized into a comprehensive review. Results: A Lactobacillus-dominant microbiome, particularly with L. crispatus, creates a protective environment through lactic acid production, maintenance of low pH, and anti-inflammatory immune modulation, facilitating HPV clearance. Dysbiosis, often characterized by a dominance of L. iners and overgrowth of anaerobic bacteria, fosters chronic inflammation, cytokine imbalance, and a microenvironment conducive to HPV persistence and progression. Hormonal changes and menopause exacerbate these microbial shifts, increasing the risk of cervical lesions. Studies suggest that cytokine profiles and antimicrobial peptides significantly influence local immune responses, further modulating infection outcomes. Conclusions: The cervicovaginal microbiome is a critical determinant in HPV infection outcomes, with therapeutic potential for modulating the microbiome to enhance immune responses and prevent cervical cancer. Personalized microbiome-targeted therapies may offer a novel avenue for managing HPV and reducing cervical cancer incidence.

The Promising Biological Role of Postbiotics in Treating Human Infertility

Infertility poses a global challenge that impacts a significant proportion of the populace. Presently, there is a substantial emphasis on investigating the potential of probiotics and their derivatives, called postbiotics, as an alternative therapeutic strategy for addressing infertility. The term of "postbiotics" refers to compounds including peptides, enzymes, teichoic acids, and muropeptides derived from peptidoglycans, polysaccharides, proteins, and organic acids that are excreted by living bacteria or released after bacterial lysis. Postbiotics exhibit the capacity to enhance fertility in both men and women, with their impact on male reproductive function (specifically testicular function, semen quality, and prostate health) and female reproductive health (including modulation of vaginal microbiota and restoration thereof) being posited as potential mechanisms by which postbiotics may enhance fertility. This review highlights definitions of postbiotics, as well as their biological role in treatment of infertility.

Metagenomic Composition and Predicted Metabolic Pathway Analyses of the Endometrial and Rectal Microbiota in Dairy Cows Following the Introduction of a Complex Feed Additive

BACKGROUND

The microbiome composition in dairy cows (Bos taurus) directly impacts on health and reproductive performance. This study aimed to determine the metagenomic composition and predicted microbial community functions in the endometrium and rectal chyme of cows fed a complex feed additive (CFA). The latter included the Bacillus mucilaginosus 159 strain, a short-chain fatty acid, plus essential oils.

METHODS

Clinically healthy cows were divided into two groups (n = 15 in each): (I) a control group fed the standard diet, and (II) an experimental group. CFA was introduced into the diet of Group II during the entire transit period at a dose of 50 g per animal per day; moreover, all animals received Pen-Strep 400 antibiotics to prevent endometritis and other pathologies. The microbial community composition from the endometrium and rectal chyme biotopes was assessed using targeted next-generation sequencing.

RESULTS

Significant changes were observed in the composition and predicted metabolic pathways due to the CFA administration, with the endometrial microbiota being more responsive to CFA than the intestinal chyme microbiome. Remarkably, the Actinobacteriota representatives disappeared in the endometrium of Group II animals compared to controls, whose content ranged from 0.34 to 3.3%. The use of CFA also resulted in a less pronounced effect in four predicted metabolic pathways for microbial degradation of catechol in the endometrium compared to controls (p < 0.05).

CONCLUSIONS

Our findings support the concept of a relationship between the gut microbiome and the reproductive system microflora of cows, as we observed changes in the composition and predicted metabolic pathways of the endometrial microbiota after orally administering CFA. This emphasizes the need for an integrated approach combining the correction of microecological disorders in the intestines and the reproductive system simultaneously.

The Hygienic Significance of Microbiota and Probiotics for Human Wellbeing

The human body can be viewed as a combination of ecological niches inhabited by trillions of bacteria, viruses, fungi, and parasites, all united by the microbiota concept. Human health largely depends on the nature of these relationships and how they are built and maintained. However, personal hygiene practices have historically been focused on the wholesale elimination of pathogens and "hygiene-challenging microorganisms" without considering the collateral damage to beneficial and commensal species. The microbiota can vary significantly in terms of the qualitative and quantitative composition both between different people and within one person during life, and the influence of various environmental factors, including age, nutrition, bad habits, genetic factors, physical activity, medication, and hygienic practices, facilitates these changes. Disturbance of the microbiota is a predisposing factor for the development of diseases and also greatly influences the course and severity of potential complications. Therefore, studying the composition of the microbiota of the different body systems and its appropriate correction is an urgent problem in the modern world. The application of personal hygiene products or probiotics must not compromise health through disruption of the healthy microbiota. Where changes in the composition or metabolic functions of the microbiome may occur, they must be carefully evaluated to ensure that essential biological functions are unaffected. As such, the purpose of this review is to consider the microbiota of each of the "ecological niches" of the human body and highlight the importance of the microbiota in maintaining a healthy body as well as the possibility of its modulation through the use of probiotics for the prevention and treatment of certain human diseases.

Insights into Women's health: Exploring the vaginal microbiome, quorum sensing dynamics, and therapeutic potential of quorum sensing quenchers

The vaginal microbiome is an important aspect of women's health that changes dynamically with various stages of the woman's life. Just like the gut microbiome, the vaginal microbiome can also be affected by pathologies that dramatically change the typical composition of native vaginal microorganisms. However, the mechanism as to how both vaginal endemic and gut endemic opportunistic microbes can express pathogenicity in vaginal polymicrobial biofilms is poorly understood. Quorum sensing is the cellular density-dependent bacterial and fungal communication process in which chemical signaling molecules, known as autoinducers, activate expression for genes responsible for virulence and pathogenicity, such as biofilm formation and virulence factor production. Quorum sensing inhibition, or quorum quenching, has been explored as a potential therapeutic route for both bacterial and fungal infections. By applying these quorum quenchers, one can reduce biofilm formation of opportunistic vaginal microbes and combine them with antibiotics for a synergistic effect. This review aims to display the relationship between the vaginal and gut microbiome, the role of quorum sensing in polymicrobial biofilm formation which cause pathology in the vaginal microbiome, and how quorum quenchers can be utilized to attenuate the severity of bacterial and fungal infections.

Vaginal Microbiome: Environmental, Biological, and Racial Influences on Gynecological Health Across the Lifespan

The human vaginal microbiome (VMB) is a complex and unique ecosystem composed of various microorganisms, including bacteria, fungi, archaea, viruses, and candidate phyla radiation. A healthy VMB is often characterized by the presence of Lactobacillus species, which play a crucial role in protecting and maintaining homeostasis within the vaginal environment. When this balance is disrupted, the protection of the vaginal epithelium weakens, leading to a reduction in Lactobacillus species and an increased risk of various gynecological and reproductive health issues. However, this generalized description can lead to misconceptions and an incomplete understanding of vaginal health, as Lactobacillus is not always dominant across all ages and racialized groups. Therefore, this review provides a comprehensive analysis of the environmental, biological, and racial influences on the VMB at each stage of a woman's life, highlighting their implications for gynecological health and offering a holistic understanding of the VMB for all women.

Understanding vaginal biofilms: The first step in harnessing antimicrobial nanomedicine

In spite of multipurpose technologies offering broad-spectrum prevention for sexually transmitted infections (STIs) and contraception, the STIs incidences rise worldwide. The situation is even more alarming considering continuous rise in antimicrobial resistance (AMR) that limits therapy options. In this review we address the specific challenges of efficiently treating vaginal infections locally, at the infection site, by understanding the underlying barriers to efficient treatment such as vaginal biofilms. Knowledge on vaginal biofilms remains, up to now, rather scarce and requires more attention. We therefore propose a 'back to basics' insight that seeks to probe the complexity and role of the vaginal microbiota, its relationship with vaginal biofilms and implications to future therapeutic modalities utilizing advanced nano delivery systems. Our key objective is to highlight the interplay between biofilm, (nano)formulation and therapy outcome rather than provide an overview of all nanoformulations that were challenged against biofilms. We focused on the anatomy of the female reproductive organ and its physiological changes from birth, the unique vaginal microenvironment in premenopausal and postmenopausal women, vaginal biofilm infections and current nanomedicine-based approaches to treat infections in the vaginal site. Finally, we offer our perspectives on the current challenges associated with vaginal delivery and key considerations that can aid in the design and development of safer and potent products against persisting vaginal infections.

Infertility, IL-17, IL-33 and Microbiome Cross-Talk: The Extended ARIA-MeDALL Hypothesis

Infertility, defined as the inability to obtain pregnancy after 12 months of regular unprotected sexual intercourse, has increased in prevalence over the past decades, similarly to chronic, allergic, autoimmune, or neurodegenerative diseases. A recent ARIA-MeDALL hypothesis has proposed that all these diseases are linked to dysbiosis and to some cytokines such as interleukin 17 (IL-17) and interleukin 33 (IL-33). Our paper suggests that endometriosis, a leading cause of infertility, is linked to endometrial dysbiosis and two key cytokines, IL-17 and IL-33, which interact with intestinal dysbiosis. Intestinal dysbiosis contributes to elevated estrogen levels, a primary factor in endometriosis. Estrogens strongly activate IL-17 and IL-33, supporting the existence of a gut-endometrial axis as a significant contributor to infertility.

Vaginal microbiota, menopause, and the use of menopausal hormone therapy: a cross-sectional, pilot study in Chinese women

OBJECTIVE

To compare the vaginal microbiota of premenopausal and postmenopausal women and postmenopausal women undergoing menopausal hormone therapy (MHT) and examine the association between vaginal microbiota and genitourinary syndrome of menopause (GSM).

METHODS

This cross-sectional study classified 94 women aged 40 to 60 years into three groups: premenopausal (Pre, n = 32), postmenopausal (Post, n = 30), and postmenopausal women who received MHT orally (Post + MHT, n = 32). Neither the Pre nor the Post group received hormone therapy within the past 6 months. Postmenopausal women who received vaginal MHT were not included. Vaginal swabs were obtained, and microbial composition was characterized by 16S rRNA gene sequencing targeting the V3 to V4 region. Clinical data were collected and serum sex hormones were measured. The most bothersome symptom approach and vaginal health index were used to evaluate GSM. Mann-Whitney U or Kruskal-Wallis ANOVA followed by multiple comparison tests were performed for comparison between or across groups. The correlations between GSM symptom scores and vaginal microbiota were determined using Spearman's correlation analysis.

RESULTS

The vaginal community of postmenopausal women was characterized by a decreased abundance of Lactobacillus (Post 18% vs Pre 69%); an increased abundance of several anaerobic bacteria, including Prevotella , Escherichia-Shigella , and Bifidobacterium ; and a higher microbial diversity ( P < 0.001 for Shannon and Simpson indexes) than those of premenopausal women. The vaginal community of postmenopausal women who received MHT had an increased abundance of Lactobacillus (54%) and lower microbial diversity ( P < 0.001 for Shannon and Simpson indexes) than the postmenopausal women. The vaginal microbial community composition of the Pre group shared more similarity with that of the Post + MHT group (Adonis P = 0.051) than with that of the Post group (Adonis P < 0.001). A decreased abundance of Lactobacillus and high diversity in the vaginal community were found in women with moderate to severe GSM symptoms.

CONCLUSIONS

Among Chinese postmenopausal women, those receiving MHT had higher Lactobacillus abundance but lower abundance of diverse anaerobes and diversity of the vaginal microbial community compared to non-MHT women. MHT in postmenopausal women may potentially contribute to reestablishing vaginal microbiota homeostasis. Findings in this pilot study, however, need to be examined in larger, prospective studies.

Schistosomiasis-Microbiota Interactions: A Systematic Review and Meta-Analysis

INTRODUCTION

Schistosomiasis, a tropical disease affecting humans and animals, affected 251.4 million people in 2021. Schistosoma mansoni, S. haematobium, S. intercalatum, and S. japonicum are primary human schistosomes, causing tissue damage, granulomas, ulceration, hemorrhage, and opportunistic pathogen entry. The gut and urinary tract microbiota significantly impact a host's susceptibility to schistosomiasis, disrupting microbial balance; however, this relationship is not well understood. This systematic review and meta-analysis explores the intricate relationship between schistosomiasis and the host's microbiota, providing crucial insights into disease pathogenesis and management.

METHODS

This systematic review used PRISMA guidelines to identify peer-reviewed articles on schistosomiasis and its interactions with the host microbiome, using multiple databases and Google Scholar, providing a robust dataset for analysis. The study utilized Meta-Mar v3.5.1; descriptive tests, random-effects models, and subgroups were analyzed for the interaction between Schistosomiasis and the microbiome. Forest plots, Cochran's Q test, and Higgins' inconsistency statistic (I2) were used to assess heterogeneity.

RESULTS

The human Schistosoma species were observed to be associated with various bacterial species isolated from blood, stool, urine, sputum, skin, and vaginal or cervical samples. A meta-analysis of the interaction between schistosomiasis and the host microbiome, based on 31 studies, showed 29,784 observations and 5871 events. The pooled estimates indicated a significant association between schistosomiasis and changes in the microbiome of infected individuals. There was considerable heterogeneity with variance effect sizes (p < 0.0001). Subgroup analysis of Schistosoma species demonstrated that S. haematobium was the most significant contributor to the overall heterogeneity, accounting for 62.1% (p < 0.01). S. mansoni contributed 13.0% (p = 0.02), and the coinfection of S. haematobium and S. mansoni accounted for 16.8% of the heterogeneity (p < 0.01), contributing to the variability seen in the pooled analysis. Similarly, praziquantel treatment (RR = 1.68, 95% CI: 1.07-2.64) showed high heterogeneity (Chi2 = 71.42, df = 11, p < 0.01) and also indicated that Schistosoma infections in males (RR = 1.46, 95% CI: 0.00 to 551.30) and females (RR = 2.09, 95% CI: 0.24 to 18.31) have a higher risk of altering the host microbiome.

CONCLUSIONS

Schistosomiasis significantly disrupts the host microbiota across various bodily sites, leading to increased susceptibility to different bacterial taxa such as E. coli, Klebsiella, Proteus, Pseudomonas, Salmonella, Staphylococcus, Streptococcus, and Mycobacterium species (M. tuberculosis and M. leprae). This disruption enables these bacteria to produce toxic metabolites, which in turn cause inflammation and facilitate the progression of disease. The impact of schistosomiasis on the vaginal microbiome underscores the necessity for gender-specific approaches to treatment and prevention. Effective management of female genital schistosomiasis (FGS) requires addressing both the parasitic infection and the resulting microbiome imbalances. Additionally, praziquantel-treated individuals have different microbiome compositions compared to individuals with no praziquantel treatment. This suggests that combining praziquantel treatment with probiotics could potentially decrease the disease severity caused by an altered microbiome.

Controlled release of microorganisms from engineered living materials

Probiotics offer therapeutic benefits by modulating the local microbiome, the host immune response, and the proliferation of pathogens. Probiotics have the potential to treat complex diseases, but their persistence or colonization is required at the target site for effective treatment. Although probiotic persistence can be achieved by repeated delivery, no biomaterial that releases clinically relevant doses of metabolically active probiotics in a sustained manner has been previously described. Here, we encapsulate stiff probiotic microorganisms within relatively less stiff hydrogels and show a generic mechanism where these microorganisms proliferate and induce hydrogel fracture, resulting in microbial release. Importantly, this fracture-based mechanism leads to microorganism release with zero-order release kinetics. Using this mechanism, small (∼1 μL) engineered living materials (ELMs) release >10 8 colony-forming-units (CFUs) of E. coli in 2 h. This release is sustained for at least 10 days. Cell release can be varied by more than three orders of magnitude by varying initial cell loading and modulating the mechanical properties of encapsulating matrix. As the governing mechanism of microbial release is entirely mechanical, we demonstrate controlled release of model Gram-negative, Gram-positive, and fungal probiotics from multiple hydrogel matrices.

SIGNIFICANCE

Probiotics offer therapeutic benefits and have the potential to treat complex diseases, but their persistence at the target site is often required for effective treatment. Although probiotic persistence can be achieved by repeated delivery, no biomaterial that releases metabolically active probiotics in a sustained manner has been developed yet. This work demonstrates a generic mechanism where stiff probiotics encapsulated within relatively less stiff hydrogels proliferate and induce hydrogel fracture. This allows a zero-order release of probiotics which can be easily controlled by adjusting the properties of the encapsulating matrices. This generic mechanism is applicable for a wide range of probiotics with different synthetic matrices and has the potential to be used in the treatment of a broad range of diseases.

An updated study of the relationship between bacterial infections and women's immune system, focusing on bacterial compositions with successful pregnancy

Genital tract infections can cause a variety of harmful health outcomes, including endometritis, bacterial vaginosis, and pelvic inflammatory disease, in addition to infertility. Anaerobic bacteria, such as Gardnerella vaginalis, Megasphaera spp., and Atopobium vaginae, are more commonly identified in cases of bacterial vaginosis than lactobacilli. It is unknown how the microorganisms that cause pelvic inflammatory diseases and endometritis enter the uterus. Both prospective and retrospective research have connected pelvic inflammatory disorders, chronic endometritis, and bacterial vaginosis to infertility. Similar to bacterial vaginosis, endometritis-related infertility is probably caused by a variety of factors, such as inflammation, immune system recognition of sperm antigens, bacterial toxins, and a higher risk of STDs. Preconception care for symptomatic women may include diagnosing and treating pelvic inflammatory disease, chronic endometritis, and bacterial vaginosis before conception to optimize the results of both natural and assisted reproduction.

Probiotics in the Management of Vulvovaginal Candidosis

Vulvovaginal candidosis (VVC) represents a frequent and cumbersome vaginal infection. Recurrent and/or persistent infections remain common among a significant number of patients despite the use of antifungals. Probiotics offer a promising adjunctive or alternative therapeutic strategy to antifungals in the management of VVC. We aimed to explore and thoroughly examine the various roles and potential applications of probiotics in VVC. A comprehensive literature search was conducted to identify relevant clinical trials and systematic reviews that examine the effectiveness of probiotics in the treatment and prevention of VVC and recurrent VVC (rVVC). Following the initial screening of 4563 articles, a total of 25 clinical studies and seven systematic reviews were finally included in this analysis. The studies reviewed provide a generally positive yet inconsistent view of the efficacy of probiotics in managing VVC, including clinical, mycological response, and prevention perspectives. Nonetheless, fluconazole remains more effective than probiotics in treating VVC, while the combination of the two seems to reduce recurrence and improve symptoms significantly. For prevention, probiotics seem to improve vaginal health and reduce symptoms, while safety and tolerability are consistently reported across the studies, affirming that probiotics represent a low-risk intervention. However, clear conclusions are difficult to establish since relative studies explore different clinical endpoints and follow-up times, variable populations are included, different probiotics are used, and diverse schedules and regimens are administered. We propose that future studies should study the benefit of probiotics in well-defined categories such as (1) treatment with acute probiotics instead of antifungals, (2) adjuvant probiotic therapy together or after antifungals, and (3) VVC recurrence prevention using probiotics.

Draft genome assemblies of one Lactobacillus gasseri strain and two Lactobacillus jensenii strains isolated from voided urine samples

We present the draft genome for three Lactobacillus strains isolated from female urine specimens: Lactobacillus gasseri UMB1673, Lactobacillus jensenii UMB1855, and Lactobacillus jensenii UMB5069. Focusing on strains within the female urinary microbiome can provide a more well-rounded understanding of the microbial community and its influence on health and disease.

Exploring Oral and Vaginal Probiotic Solutions for Women's Health from Puberty to Menopause: A Narrative Review

The vaginal microbiota (VMB) plays a crucial role in women's health from puberty to menopause. Traditional studies have focused on the microorganisms present within the vaginal environment and their roles in disease onset. However, the dynamic relationship between the VMB and its host remains underexplored. Common narratives emphasize the presence of Lactobacilli spp. as an indicator of vaginal health, yet this does not fully explain the occurrence of asymptomatic yet significant dysbiosis. Moreover, a wide array of bacterial types can inhabit the vaginal environment, suggesting that probiotic Lactobacilli could offer a natural, safe solution for balancing vaginal microbiota. This review examines the current literature on VMB, key factors affecting its composition, and the changes it undergoes during different life stages. Given the health-promoting potential of probiotics, we also examine their role in maintaining a healthy VMB and overall women's health throughout life.

Reproductive Tract Microbiota of Mares

The female reproductive tract microbiota is a complex community of microorganisms that might be crucial in maintaining a healthy reproductive environment. Imbalances in the bacterial community (dysbiosis) and the reduction of beneficial organisms and pathogen proliferation are associated with disease. Endometritis is a common cause of fertility problems in mares, and it is still challenging to diagnose and treat based on routine culture results of certain microorganisms. Although high-throughput sequencing studies provide helpful information regarding the composition of the reproductive tract microbiota in mares, there are still challenges in defining a "normal" microbiota. The primary objective of this literature review is to summarize the current knowledge regarding the microbiota present in the reproductive tract of mares, including the vagina, cervix, and uterus. The second objective is to describe the relevant factors that can impact the reproductive microbiota of mares, including the estrous cycle stage, the type of species (genera) investigated, season, and geographic location. The rationality of identifying the normal microbiota in the reproductive tract of a mare will likely aid in understanding the impact of the microbiota on the host's reproductive health and contribute to the treatment and prevention of equine sub and infertility issues.

Vaginal and Uterine Microbiota of Healthy Maiden Mares during Estrus

This descriptive cross-sectional study compared the microbiota of the uterus, vagina, clitoral fossa (CF), and perineal skin in healthy maiden mares during estrus. Twelve synchronized, healthy maiden mares (3-4 years old) from one single recipient mare herd were included. Microbial communities were characterized by amplifying the V3-V4 region of the 16S rRNA gene using the Illumina MiSeq platform. The uterine and vaginal microbiota had significantly lower richness (Chao-1) than the skin (p < 0.05). The uterine and vagina bacterial composition was similar in presence and abundance and could be differentiated from that of the CF and perineal skin. The microbial composition (Jaccard and Bray-Curtis distances) significantly differed across body-site locations (p < 0.05), which explained approximately 14% and 19% of the variation in microbial composition for Jaccard and Bray-Curtis distances, respectively. Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes were the dominant taxa in the uterus and vagina, with higher proportions of Proteobacteria in the vaginal samples compared to the uterine samples. Streptococcaceae and Staphylococcaceae were present in high abundance in the uterine and vaginal samples, while Lactobacillaceae were not (<10%). We demonstrate that the uterine and vaginal microbiota of healthy maiden mares during estrus is similar but both distinct from that of the CF and perineal skin.

Biomarker Identification for Preterm Birth Susceptibility: Vaginal Microbiome Meta-Analysis Using Systems Biology and Machine Learning Approaches

PROBLEM

The vaginal microbiome has a substantial role in the occurrence of preterm birth (PTB), which contributes substantially to neonatal mortality worldwide. However, current bioinformatics approaches mostly concentrate on the taxonomic classification and functional profiling of the microbiome, limiting their abilities to elucidate the complex factors that contribute to PTB.

METHOD OF STUDY

A total of 3757 vaginal microbiome 16S rRNA samples were obtained from five publicly available datasets. The samples were divided into two categories based on pregnancy outcome: preterm birth (PTB) (N = 966) and term birth (N = 2791). Additionally, the samples were further categorized based on the participants' race and trimester. The 16S rRNA reads were subjected to taxonomic classification and functional profiling using the Parallel-META 3 software in Ubuntu environment. The obtained abundances were analyzed using an integrated systems biology and machine learning approach to determine the key microbes, pathways, and genes that contribute to PTB. The resulting features were further subjected to statistical analysis to identify the top nine features with the greatest effect sizes.

RESULTS

We identified nine significant features, namely Shuttleworthia, Megasphaera, Sneathia, proximal tubule bicarbonate reclamation pathway, systemic lupus erythematosus pathway, transcription machinery pathway, lepA gene, pepX gene, and rpoD gene. Their abundance variations were observed through the trimesters.

CONCLUSIONS

Vaginal infections caused by Shuttleworthia, Megasphaera, and Sneathia and altered small metabolite biosynthesis pathways such as lipopolysaccharide folate and retinal may increase the susceptibility to PTB. The identified organisms, genes, pathways, and their networks may be specifically targeted for the treatment of bacterial infections that increase PTB risk.

Does "all disease begin in the gut"? The gut-organ cross talk in the microbiome

The human microbiome, a diverse ecosystem of microorganisms within the body, plays pivotal roles in health and disease. This review explores site-specific microbiomes, their role in maintaining health, and strategies for their upkeep, focusing on oral, lung, vaginal, skin, and gut microbiota, and their systemic connections. Understanding the intricate relationships between these microbial communities is crucial for unraveling mechanisms underlying human health. Recent research highlights bidirectional communication between the gut and distant microbiome sites, influencing immune function, metabolism, and disease susceptibility. Alterations in one microbiome can impact others, emphasizing their interconnectedness and collective influence on human physiology. The therapeutic potential of gut microbiota in modulating distant microbiomes offers promising avenues for interventions targeting various disorders. Through interdisciplinary collaboration and technological advancements, we can harness the power of the microbiome to revolutionize healthcare, emphasizing microbiome-centric approaches to promote holistic well-being while identifying areas for future research.

The Role of Prevotella Species in Female Genital Tract Infections

Female genital tract infections (FGTIs) include vaginal infections (e.g., bacterial vaginosis [BV]), endometritis, pelvic inflammatory disease [PID], and chorioamnionitis [amniotic fluid infection]. They commonly occur in women of reproductive age and are strongly associated with multiple adverse health outcomes including increased risk of HIV/sexually transmitted infection acquisition and transmission, infertility, and adverse birth outcomes such as preterm birth. These FGTIs are characterized by a disruption of the cervicovaginal microbiota which largely affects host immunity through the loss of protective, lactic acid-producing Lactobacillus spp. and the overgrowth of facultative and strict anaerobic bacteria. Prevotella species (spp.), anaerobic Gram-negative rods, are implicated in the pathogenesis of multiple bacterial FGTIs. Specifically, P. bivia, P. amnii, and P. timonensis have unique virulence factors in this setting, including resistance to antibiotics commonly used in treatment. Additionally, evidence suggests that the presence of Prevotella spp. in untreated BV cases can lead to infections of the upper female genital tract by ascension into the uterus. This narrative review aims to explore the most common Prevotella spp. in FGTIs, highlight their important role in the pathogenesis of FGTIs, and propose future research in this area.

Harnessing the power within: engineering the microbiome for enhanced gynecologic health

Abstract

Although numerous studies have demonstrated the impact of microbiome manipulation on human health, research on the microbiome's influence on female health remains relatively limited despite substantial disease burden. In light of this, we present a selected review of clinical trials and preclinical studies targeting both the vaginal and gut microbiomes for the prevention or treatment of various gynecologic conditions. Specifically, we explore studies that leverage microbiota transplants, probiotics, prebiotics, diet modifications, and engineered microbial strains. A healthy vaginal microbiome for females of reproductive age consists of lactic acid-producing bacteria predominantly of the Lactobacillus genus, which serves as a protective barrier against pathogens and maintains a balanced ecosystem. The gut microbiota's production of short-chain fatty acids, metabolism of primary bile acids, and modulation of sex steroid levels have significant implications for the interplay between host and microbes throughout the body, ultimately impacting reproductive health. By harnessing interventions that modulate both the vaginal and gut microbiomes, it becomes possible to not only maintain homeostasis but also mitigate pathological conditions. While the field is still working toward making broad clinical recommendations, the current studies demonstrate that manipulating the microbiome holds great potential for addressing diverse gynecologic conditions.

Lay summary

Manipulating the microbiome has recently entered popular culture, with various diets thought to aid the microbes that live within us. These microbes live in different locations of our body and accordingly help us digest food, modulate our immune system, and influence reproductive health. The role of the microbes living in and influencing the female reproductive tract remains understudied despite known roles in common conditions such as vulvovaginal candidiasis (affecting 75% of females in their lifetime), bacterial vaginosis (25% of females in their lifetime), cervical HPV infection (80% of females in their lifetime), endometriosis (6-10% of females of reproductive age), and polycystic ovary syndrome (10-12% of females of reproductive age). Here, we review four different approaches used to manipulate the female reproductive tract and gastrointestinal system microbiomes: microbiota transplants, probiotics, prebiotics, and dietary interventions, and the use of engineered microbial strains. In doing so, we aim to stimulate discussion on new ways to understand and treat female reproductive health conditions.

A molecular view on the interference established between vaginal Lactobacilli and pathogenic Candida species: Challenges and opportunities for the development of new therapies

Vaginal infectious diseases caused by viruses and bacteria have been linked to the occurrence of dysbiosis, that is, a reduction in the abundance of the normally dominating vaginal Lactobacillus species. Mucosal infections in the vagina and/or vulva caused by Candida species, usually known as vulvovaginal candidiasis (or VVC), are among the leading causes of diseases in the vaginal tract. The existence of a clear link between the occurrence of dysbiosis and the development of VVC is still unclear, although multiple observations point in that direction. Based on the idea that vaginal health is linked to a microbiota dominated by lactobacilli, several probiotics have been used in management of VVC, either alone or in combination with antifungals, having obtained different degrees of success. In most cases, the undertaken trials resorted to lactobacilli species other than those indigenous to the vaginal tract, although in vitro these vaginal species were shown to reduce growth, viability and virulence of Candida. In this paper we overview the role of lactobacilli and Candida in the vaginal micro- and myco-biomes, while discussing the results obtained in what concerns the establishment of interference mechanisms in vivo and the environmental factors that could determine that. We also overview the molecular mechanisms by which lactobacilli species have been shown to inhibit pathophysiology of Candida, including the description of the genes and pathways determining their ability to thrive in the presence of each other. In a time where concerns are increasing with the emergence of antifungal resistance and the slow pace of discovery of new antifungals, a thorough understanding of the molecular mechanisms underneath the anti-Candida effect prompted by vaginal lactobacilli is of utmost importance to assure a knowledge-based design of what can be a new generation of pharmaceuticals, eventually focusing therapeutic targets other than the usual ones.

The Postmenopausal Vaginal Microbiome and Genitourinary Syndrome of Menopause

This review summarizes our current understanding of associations of the postmenopausal vaginal microbiome with genitourinary syndrome of menopause. We review the normal postmenopausal microbiota, examine the association of the microbiome with vulvovaginal symptoms, describe microbial communities associated with physical and laboratory findings, and report the impact of different treatments for genitourinary syndrome of menopause on microbiota and symptom improvement. Postmenopausal vaginal symptoms have an underlying pathophysiology that has not been fully elucidated. Estrogen treatment may not be sufficient to relieve symptoms of vaginal discomfort in all postmenopausal individuals. In addition, other interventions targeted at changing the microbiota or pH do not consistently improve symptom severity.

Analysis of Vaginal Microbiota Variations in the Third Trimester of Pregnancy and Their Correlation with Preterm Birth: A Case-Control Study

This study conducted a detailed analysis of the vaginal microbiota in pregnant women to explore its correlation with preterm birth (PTB) outcomes. The primary objective was to identify microbial variations associated with increased PTB risk. Secondary objectives included investigating how changes in microbial composition relate to the local immune environment and PTB. Utilizing a retrospective case-control design, the study involved pregnant women with liveborn infants between 2019 and 2023. In total, 89 women who delivered preterm and 106 term deliveries were included. Data collection focused on third-trimester vaginal cultures. Statistically significant differences were observed between the preterm and full-term groups in several areas. The median white blood cell count (10.2 × 103/mm3 vs. 7.6 × 103/mm3, p = 0.009) and neutrophil count (7.2 × 103/mm3 vs. 5.1 × 103/mm3, p < 0.001) were higher in the preterm group. Vaginal pH was also elevated in preterm births (5.6 vs. 4.4, p < 0.001), with a higher prevalence of bacterial vaginosis (29.2% vs. 12.3%, p = 0.001) as indicated by the Nugent Score. The study noted a significant association of PTB with the presence of Candida spp. (OR = 1.84, p = 0.018), Gardnerella vaginalis (OR = 2.29, p = 0.003), Mycoplasma hominis (OR = 1.97, p = 0.007), and Ureaplasma urealyticum (OR = 2.43, p = 0.001). Conversely, a reduction in Lactobacillus spp. correlated with a decreased PTB risk (OR = 0.46, p = 0.001). The study provides compelling evidence that specific vaginal microbiota components, particularly certain pathogenic bacteria and an altered Lactobacillus profile, are significantly associated with PTB risk. These findings highlight the potential of targeting microbial factors in strategies aimed at reducing PTB rates. Further research is necessary to fully understand the complex interplay between microbial dynamics, host immunity, and PTB outcomes.

Different Forms of TFF3 in the Human Endocervix, including a Complex with IgG Fc Binding Protein (FCGBP), and Further Aspects of the Cervico-Vaginal Innate Immune Barrier

TFF3 is a typical secretory poplypeptide of mucous epithelia belonging to the trefoil factor family (TFF) of lectins. In the intestine, respiratory tract, and saliva, TFF3 mainly exists as a high-molecular-mass complex with IgG Fc binding protein (FCGBP), which is indicative of a role in mucosal innate immunity. For the first time, we identified different forms of TFF3 in the endocervix, i.e., monomeric and homodimeric TFF3, as well as a high-molecular-mass TFF3-FCGBP complex; the latter also exists in a hardly soluble form. Immunohistochemistry co-localized TFF3 and FCGBP. Expression analyses of endocervical and post-menopausal vaginal specimens revealed a lack of mucin and TFF3 transcripts in the vaginal specimens. In contrast, genes encoding other typical components of the innate immune defense were expressed in both the endocervix and vagina. Of note, FCGBP is possibly fucosylated. Endocervical specimens from transgender individuals after hormonal therapy showed diminished expression, particularly of FCGBP. Furthermore, mucus swabs from the endocervix and vagina were analyzed concerning TFF3, FCGBP, and lysozyme. It was the aim of this study to illuminate several aspects of the cervico-vaginal innate immune barrier, which is clinically relevant as bacterial and viral infections are also linked to infertility, pre-term birth and cervical cancer.

Bacterial Vaginosis (BV) and Vaginal Microbiome Disorders in Women Suffering from Polycystic Ovary Syndrome (PCOS)

Introduction: Polycystic ovary syndrome (PCOS) is a multifactorial, heterogeneous endocrine and metabolic disorder in women. Due to its association with the menstrual cycle and fertility disorders, the importance of this problem is emphasized especially in patients of reproductive age. Based on a number of analyses, the effect of PCOS on altering the diversity of the microbiome (e.g., intestinal or vaginal) is suggested. Vaginal dysbiosis can result in BV (bacterial vaginosis). The purpose of this study was to assess the prevalence of BV in patients with PCOS, as well as to determine the most reliable diagnostic factors. Material and Methods: Retrospective analysis of microbiological findings (2018-2022) of PCOS patients (n = 594) of reproductive age. The present analysis focused on the results of patients with PCOS (n = 380) and vaginal discharge with pH ≥ 4.4 and suspected BV. Biological material was a vaginal swab/vaginal secretion. The most commonly used routine methods for assessing BV were the Amsel analysis and the Nugent scoring system. Results: Patients with PCOS and vaginal fluid pH ≥ 4.4 and suspected BV (n = 380) accounted for 64% of all PCOS patients (n = 594). The relationship between pH and detection of "clue cells" showed significant dependency and increased with leukocytes. The pH measurement also showed dependency on high G. vaginalis counts. In addition, the elimination of lactic acid bacteria (LAB) in vaginal secretions was associated with an increase in the number of leukocytes with increasing pH values. A marked increase in G. vaginalis was found in more than half (56.8%) of PCOS women (n = 380) with suspected BV. No dependency was observed between the absence of LAB and the diagnosis of BV on a positive G. vaginalis culture. Of the n = 380 patients with PCOS, 191 (50%) had a Nugent score ≥ 7 positive for BV. No dependency was observed between the number of patients with Candida sp. in vaginal secretions and pH, BV (with clue cells), or elevated leukocyte levels. The LRM was adjusted and the statistical model represented by the following formula was obtained: log(p/(1 - p)) = -1.18 + 1.24 × Group4.6 + 1.08 × Group4.8 + 1.66 × Group5.4. Conclusions: Based on the present analysis, BV appears to be more common in patients with PCOS than in the non-PCOS population. Chronic inflammation in PCOS patients and abnormalities in the vaginal microbiome may predispose to the development of BV. In women with PCOS, BV may be one of the unrecognized causes of infertility or complications of pregnancy. Despite the potential link between PCOS and the development of BV, the extent to which this syndrome contributes to vaginal dysbiosis and reproductive complications requires further study.

Human vaginal microbiota colonization is regulated by female sex hormones in a mouse model

Introduction

Clinically, a Lactobacillus rich vaginal microbiota (VMB) is considered optimal for reproductive outcomes, while a VMB populated by anaerobes is associated with dysbiosis and the clinical condition bacterial vaginosis (BV), which is linked to increased susceptibility to sexually transmitted infections and adverse reproductive outcomes. Mouse models that mimic eubiotic and dysbiotic VMB are currently lacking but could play a critical role in improving protective interventions.

Methods

In this study, probiotic, eubiotic, and dysbiotic models were developed in C57BL/6 mice, using probiotic strains Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14, eubiotic Lactobacillus crispatus, or dysbiotic Gardnerella vaginalis strains. Endogenous sex hormones were manipulated by either ovariectomizing (OVX) mice or administering 17β-estradiol or progesterone pellets in OVX mice. Hormone-altered mice were inoculated with probiotic Lactobacillus species, L. crispatus, or G. vaginalis, and colonization was tracked using quantitative plating assays. Glycogen and MUC-1 levels in hormone-treated mice were determined with ELISA and MUC-1 staining.

Results

Following a single administration, L. rhamnosus and L. reuteri persisted in the mouse vaginal tract for up to eight days, L. crispatus persisted for up to three days, and G. vaginalis persisted for up to two days, as measured by quantitative plating assays and qPCR. Colonization of G. vaginalis was facilitated by the presence of mucin. The lack of endogenous hormones in OVX mice dramatically decreased VMB bacterial load compared to normal mice. None of the exogenous bacteria including Lactobacilli could colonize OVX mice for more than 24 hours. Treatment with 17β-estradiol but not progesterone restored the endogenous VMB and colonization with Lactobacilli and G. vaginalis. Interestingly, 17β-estradiol treated mice had significantly increased levels of glycogen compared to OVX and progesterone-treated mice.

Discussion

Based on the results, we have shown that estrogen played a significant role in the ability for human VMB species to colonize in our mouse models, potentially through a glycogen mediated mechanism. These results suggest there is a dynamic interaction between sex hormones and the VMB, which can affect bacterial diversity and the ability for a VMB to colonize.

Comparison of databases useful for the analysis of vaginal microbiota in Japanese women using next-generation sequencing data (QIIME 2 software)

AIMS

Approximately 10% of children are born prematurely, and bacterial vaginosis during pregnancy is associated with preterm delivery. Highly accurate species-level vaginal microflora analysis helps control bacteria-induced preterm birth. Therefore, we aimed to conduct a bioinformatic analysis of gene sequences using 16S databases and compare their efficacy in comprehensively identifying potentially pathogenic vaginal microbiota in Japanese women.

METHODS AND RESULTS

The 16 s rRNA databases, Silva, Greengenes, and the basic local alignment search tool (BLAST) were compared to determine whether the classification quality could be improved using the V3-V4 region next-generation sequencing (NGS) sequences. It was found that NGS data were aligned using the BLAST database with the QIIME 2 platform, whose classification quality was higher than that of Silva, and the combined Silva and Greengenes databases based on the mutual complementarity of the two databases.

CONCLUSIONS

The reference database selected during the bioinformatic processing influenced the recognized sequence percentage, taxonomic rankings, and accuracy. This study showed that the BLAST database was the best choice for NGS data analysis of Japanese women's vaginal microbiota.

Validation of vaginal microbiome proxies for in vitro experiments that biomimic Lactobacillus-dominant vaginal cultures

The vaginal microbiome includes diverse microbiota dominated by Lactobacillus [L.] spp. that protect against infections, modulate inflammation, and regulate vaginal homeostasis. Because it is challenging to incorporate vaginal microbiota into in vitro models, including organ-on-a-chip systems, we assessed microbial metabolites as reliable proxies in addition to traditional vaginal epithelial cultures (VECs). Human immortalized VECs cultured on transwells with an air-liquid interface generated stratified cell layers colonized by transplanted healthy microbiomes (L. jensenii- or L. crispatus-dominant) or a community representing bacterial vaginosis (BV). After 48-h, a qPCR array confirmed the expected donor community profiles. Pooled apical and basal supernatants were subjected to metabolomic analysis (untargeted mass spectrometry) followed by ingenuity pathways analysis (IPA). To determine the bacterial metabolites' ability to recreate the vaginal microenvironment in vitro, pooled bacteria-free metabolites were added to traditional VEC cultures. Cell morphology, viability, and cytokine production were assessed. IPA analysis of metabolites from colonized samples contained fatty acids, nucleic acids, and sugar acids that were associated with signaling networks that contribute to secondary metabolism, anti-fungal, and anti-inflammatory functions indicative of a healthy vaginal microbiome compared to sterile VEC transwell metabolites. Pooled metabolites did not affect cell morphology or induce cell death (∼5.5%) of VEC cultures (n = 3) after 72-h. However, metabolites created an anti-inflammatory milieu by increasing IL-10 production (p = .06, T-test) and significantly suppressing pro-inflammatory IL-6 (p = .0001), IL-8 (p = .009), and TNFα (p = .0007) compared to naïve VEC cultures. BV VEC conditioned-medium did not affect cell morphology nor viability; however, it induced a pro-inflammatory environment by elevating levels of IL-6 (p = .023), IL-8 (p = .031), and TNFα (p = .021) when compared to L.-dominate microbiome-conditioned medium. VEC transwells provide a suitable ex vivo system to support the production of bacterial metabolites consistent with the vaginal milieu allowing subsequent in vitro studies with enhanced accuracy and utility.

Enhancing Immunity and Modulating Vaginal Microflora Against Candidal Vaginitis Through Nanoemulsion Supplemented with Porphyra Oligosaccharide as an Intravaginal Vaccine Adjuvant

Background

Intravaginal vaccination is an encouraging approach to prevent infectious vaginitis, with nanoemulsions showing effectiveness as mucosal adjuvants.

Purpose

This study aimed to formulate a nanoemulsion incorporating Porphyra oligosaccharide (PO@NE) and assess its effectiveness as a mucosal adjuvant in intravaginal vaccines against candidal vaginitis.

Materials and Methods

PO@NE was prepared, and the stability, immunomodulatory activity and cytotoxicity were screened in vitro. Further, the preventive effect of PO@NE as adjuvants for heat-killed Candida albicans (HK-CA) vaccines was explored in a murine model of candidal vaginitis, in comparison with those supplemented with polysaccharide (PP@NE). The mice were intravaginally vaccinated with 106 HK-CA cells, suspended in 1% NE without or with either PO or PP at a final concentration of 6.5 μg/mL, in a total volume of 20 μL. This vaccination was intravaginally administered once a week for 3 weeks. One week following the final vaccination, the mice underwent an intravaginal challenge with 107 C. albicans cells. One week after the challenge, the mice were euthanized to isolate serum, spleen, vaginal washes, and vaginal tissues for analysis.

Results

PP@NE and PO@NE, with diameters approximately around 100 nm, exhibited exceptional stability at 4°C and low cytotoxicity when used at a concentration of 1% (v/v). Intravaginal vaccination with HK-CA adjuvanted with PO@NE effectively protected against candidal vaginitis evidenced by less Candida hyphae colonization, milder mucosal damage and cell infiltration. Moreover, enhanced mucosal antibody production, induction of T helper (Th)1 and Th17-related immune responses, enlarged the population of CD8+ cells, and elevated vaginal microflora diversity were observed in vaccinated mice. Interestingly, the potency was rather attenuated when PO@NE was replaced with PP@NE.

Conclusion

These findings indicate PO@NE as a HK-CA vaccine adjuvant for candidal vaginitis prevention via enhancement of both cellular and humoral immunity and modulation of vaginal microflora, emphasizing further intravaginal vaccination development.

Role of the vaginal microbiome in miscarriage: exploring the relationship

Miscarriage is a devastating pregnancy loss that affects many women worldwide. It is characterized as a spontaneous miscarriage that occurs before 20 weeks of gestation which affects more than 25% of pregnancies. While the causes of miscarriage are complex and multifactorial, recent research has suggested a potential role of the vaginal microbiota. The vaginal microbiome is a dynamic ecosystem of microbes that are essential for preserving vaginal health and avoiding infections. Vaginal dysbiosis has been accompanied with numerous adverse pregnancy complications, such as preterm birth. However, the effect of the vaginal microbiome in miscarriage is not fully understood. This review aims to investigate the link between vaginal microbiota and miscarriage. Also, we investigate the various mechanisms through which the vaginal microbiota may affect miscarriage. Additionally, we examine the implications of these research findings, specifically the possibility of vaginal microbiome screening and targeted interventions to prevent miscarriage.

Exploring Immunome and Microbiome Interplay in Reproductive Health: Current Knowledge, Challenges, and Novel Diagnostic Tools

The dynamic interplay between the immunome and microbiome in reproductive health is a complex and rapidly advancing research field, holding tremendously vast possibilities for the development of reproductive medicine. This immunome-microbiome relationship influences the innate and adaptive immune responses, thereby affecting the onset and progression of reproductive disorders. However, the mechanisms governing these interactions remain elusive and require innovative approaches to gather more understanding. This comprehensive review examines the current knowledge on reproductive microbiomes across various parts of female reproductive tract, with special consideration of bidirectional interactions between microbiomes and the immune system. Additionally, it explores innate and adaptive immunity, focusing on immunoglobulin (Ig) A and IgM antibodies, their regulation, self-antigen tolerance mechanisms, and their roles in immune homeostasis. This review also highlights ongoing technological innovations in microbiota research, emphasizing the need for standardized detection and analysis methods. For instance, we evaluate the clinical utility of innovative technologies such as Phage ImmunoPrecipitation Sequencing (PhIP-Seq) and Microbial Flow Cytometry coupled to Next-Generation Sequencing (mFLOW-Seq). Despite ongoing advancements, we emphasize the need for further exploration in this field, as a deeper understanding of immunome-microbiome interactions holds promise for innovative diagnostic and therapeutic strategies for reproductive health, like infertility treatment and management of pregnancy.

Collagen-Based Ovule Therapy Reduces Inflammation and Improve Cervical Epithelialization in Patients with Fungal, Viral, and Bacterial Cervico-Vaginitis

Background and Objectives: Vulvovaginal infections pose significant health challenges for women, necessitating effective treatment approaches. This retrospective observational study aimed at investigating the efficacy of collagen-based vaginal ovules therapy, specifically Plurigin Ovules, in restoring cervical epithelialization and reducing inflammation in mycotic, viral, and bacterial cervico-vaginitis. Materials and Methods: A total of 398 women with cervico-vaginitis were included in the study, categorized into three groups: bacterial cervico-vaginitis (Group A), viral cervico-vaginitis (Group B), and fungal cervico-vaginitis (Group C). Participants received vaginal therapy with Plurigin Ovules for three months. Vaginal health parameters were assessed at baseline (T0) and after six months (T1) using various diagnostic tests and analyzed with appropriate statistical tests. Results: Significant improvement in cervico-vaginitis was observed in all three groups. At T1, 87.7% patients of Group A, 66.7% of Group B, and 71.5% of Group C achieved infection resolution (all p < 0.05). Positive colposcopy results decreased across all groups (p < 0.001). Positive vaginal swabs and altered vaginal pH decreased in group A and C (p < 0.001). Positive HPV tests decreased in Group B (p < 0.001). Positive Pap tests and clinical examinations decreased significantly across all groups (p < 0.001). The odds ratios were calculated to reveal the significant associations between these diagnostic outcomes. The therapy was well-tolerated, and no major adverse events were reported. Conclusion: Plurigin Ovules exhibited promising therapeutic outcomes in the three cervico-vaginitis conditions studied. Bacterial cervico-vaginitis showed the most significant improvement, followed by fungal and viral cervico-vaginitis. These findings emphasize the potential of Plurigin Ovules as an effective therapeutic option for cervico-vaginal inflammation and infection, highlighting its role in promoting re-epithelialization and reducing inflammatory processes in the cervix and vagina.

A Narrative Review Discussing the Obstetric Repercussions Due to Alterations of Personalized Bacterial Sites Developed within the Vagina, Cervix, and Endometrium

BACKGROUND

The reproductive tract microbiota that evolved as an integrative component has been studied intensively in the last decade. As a result, novel research, clinical opportunities, and perspectives have been derived following the close investigation of this microecological environment. This has paved the way for an update to and improvement of the management strategies and therapeutic approaches. However, obscurities, contradictions, and controversies arise regarding the ascension route from the vagina to the endometrium via the cervix, with finality in adverse obstetric outcomes.

METHODS

Starting from these considerations, we aimed to gather all existing data and information from four major academic databases (PubMed, ISI Web of Knowledge, Scopus, and ScienceDirect) published in the last 13 years (2010-2023) using a controlled vocabulary and dedicated terminology to enhance the coverage, identification, and sorting of potentially eligible studies.

RESULTS

Despite the high number of returned entries (n = 804), only a slight percentage (2.73%) of all manuscripts were deemed eligible following two rounds of evaluation. Cumulatively, a low level of Lactobacillus spp. and of other core microbiota members is mandatory, with a possible eubiosis-to-dysbiosis transition leading to an impairment of metabolic and endocrine network homeostasis. This transposes into a change in the pro-inflammatory landscape and activation of signaling pathways due to activity exerted by the bacterial lipopolysaccharides (LPSs)/endotoxins that further reflect a high risk of miscarriage in various stages. While the presence of some pathogenic entities may be suggestive of an adverse obstetric predisposition, there are still pros and cons of the role of specific strains, as only the vagina and cervix have been targeted as opposed to the endometrium, which recently started to be viewed as the key player in the vagina-cervix-endometrium route. Consequently, based on an individual's profile, diet, and regime, antibiotics and probiotics might be practical or not.

CONCLUSIONS

Resident bacteria have a dual facet and are beneficial for women's health, but, at the same time, relaying on the abundance, richness, and evenness that are definitory indexes standing as intermediaries of a miscarriage.

Whole-body microbiota of newborn calves and their response to prenatal vitamin and mineral supplementation

Early life microbial colonization and factors affecting colonization patterns are gaining interest due to recent developments suggesting that early life microbiome may play a role in Developmental Origins of Health and Disease. In cattle, limited information exists on the early microbial colonization of anatomical sites involved in bovine health beyond the gastrointestinal tract. Here, we investigated 1) the initial microbial colonization of seven different anatomical locations in newborn calves and 2) whether these early life microbial communities and 3) serum cytokine profiles are influenced by prenatal vitamin and mineral (VTM) supplementation. Samples were collected from the hoof, liver, lung, nasal cavity, eye, rumen (tissue and fluid), and vagina of beef calves that were born from dams that either received or did not receive VTM supplementation throughout gestation (n = 7/group). Calves were separated from dams immediately after birth and fed commercial colostrum and milk replacer until euthanasia at 30 h post-initial colostrum feeding. The microbiota of all samples was assessed using 16S rRNA gene sequencing and qPCR. Calf serum was subjected to multiplex quantification of 15 bovine cytokines and chemokines. Our results indicated that the hoof, eye, liver, lung, nasal cavity, and vagina of newborn calves were colonized by site-specific microbiota, whose community structure differed from the ruminal-associated communities (0.64 ≥ R² ≥ 0.12, p ≤ 0.003). The ruminal fluid microbial community was the only one that differed by treatment (p < 0.01). However, differences (p < 0.05) by treatment were detected in microbial richness (vagina); diversity (ruminal tissue, fluid, and eye); composition at the phylum and genus level (ruminal tissue, fluid, and vagina); and in total bacterial abundance (eye and vagina). From serum cytokines evaluated, concentration of chemokine IP-10 was greater (p = 0.02) in VTM calves compared to control calves. Overall, our results suggest that upon birth, the whole-body of newborn calves are colonized by relatively rich, diverse, and site-specific bacterial communities. Noticeable differences were observed in ruminal, vaginal, and ocular microbiota of newborn calves in response to prenatal VTM supplementation. These findings can derive future hypotheses regarding the initial microbial colonization of different body sites, and on maternal micronutrient consumption as a factor that may influence early life microbial colonization.

The Female Reproductive Tract Microbiota: Friends and Foe

We do not seem to be the only owner of our body; it houses a large population of microorganisms. Through countless years of coevolution, microbes and hosts have developed complex relationships. In the past few years, the impact of microbial communities on their host has received significant attention. Advanced molecular sequencing techniques have revealed a remarkable diversity of the organ-specific microbiota populations, including in the reproductive tract. Currently, the goal of researchers has shifted to generate and perceive the molecular data of those hidden travelers of our body and harness them for the betterment of human health. Recently, microbial communities of the lower and upper reproductive tract and their correlation with the implication in reproductive health and disease have been extensively studied. Many intrinsic and extrinsic factors influences the female reproductive tract microbiota (FRTM) that directly affects the reproductive health. It is now believed that FRTM dominated by Lactobacilli may play an essential role in obstetric health beyond the woman's intimate comfort and well-being. Women with altered microbiota may face numerous health-related issues. Altered microbiota can be manipulated and restored to their original shape to re-establish normal reproductive health. The aim of the present review is to summarize the FRTM functional aspects that influence reproductive health.

The Impact of the Female Genital Microbiota on the Outcome of Assisted Reproduction Treatments

The vaginal microbiota plays a critical role in the health of the female genital tract, and its composition contributes to gynecological disorders and infertility. Lactobacilli are the dominant species in the female genital tract: their production of lactic acid, hydrogen peroxide, and bacteriocins prevents the invasion and growth of pathogenic microorganisms. Several factors such as hormonal changes, age of reproduction, sexual practices, menstrual cycle, pregnancy, and antimicrobial drugs use can cause imbalance and dysbiosis of the vaginal microbiota. This review aims to highlight the impact of the vaginal microbiota in Assisted Reproductive Technology techniques (ART) and it examines the factors that influence the vaginal microbiota, the consequences of dysbiosis, and potential interventions to restore a healthy female genital tract.

Feeding hempseed cake alters the bovine gut, respiratory and reproductive microbiota

A growing number of studies have investigated the feasibility of utilizing hemp by-products as livestock feedstuffs; however, their impact on livestock microbiomes remains unexplored. Here, we evaluated the effects of feeding hempseed cake on the gastrointestinal, respiratory, and reproductive microbiota in beef heifers. Angus-crossbred heifers (19-months old, initial body weight = 494 ± 10 kg [SE]) were fed a corn-based finishing diet containing 20% hempseed cake as a substitute for 20% corn dried distillers' grains with solubles (DM basis; Control; n = 16/group) for 111 days until slaughter. Ruminal fluid and deep nasopharyngeal swabs (days 0, 7, 42, 70 and 98), and vaginal and uterine swabs (at slaughter) were collected, and the microbiota assessed using 16S rRNA gene sequencing. Diet affected the community structure of the ruminal (d 7-98; 0.06 ≤ R² ≤ 0.12; P < 0.05), nasopharyngeal (d 98; R² = 0.18; P < 0.001), and vaginal (R² = 0.06; P < 0.01) microbiota. Heifers fed hempseed cake had increased microbial diversity in the rumen, reduced microbial richness in the vagina, and greater microbial diversity and richness in the uterus. In addition to the distinct microbial communities in the rumen, nasopharynx, vagina and uterus, we identified 28 core taxa that were shared (≥ 60% of all samples) across these sampling locations. Feeding hempseed cake appeared to alter the bovine gut, respiratory and reproductive microbiota. Our results suggest that future research aiming to evaluate the use of hemp by-products in livestock diet should consider their impact on animal microbiome and microbiome mediated animal health and reproductive efficiency. Our findings also highlight the need for research evaluating the impact of hemp-associated food and personal care products on the human microbiome.

Use of probiotic lactobacilli in the treatment of vaginal infections: In vitro and in vivo investigations

The vaginal microbiome is a distinct component of the human microbiome that is colonized by a wide variety of microorganisms. Lactobacilli are the most frequently identified microorganisms in the healthy human vagina. These Gram-positive bacilli can acidify the vaginal microenvironment, inhibit the proliferation of other pathogenic microorganisms, and promote the maintenance of a eubiotic vaginal microbiome. However, a vaginal flora with a reduced proportion or abundance of lactobacilli is associated with various vaginal infections that have been linked to serious health consequences such as infertility, preterm birth, pelvic inflammatory disease, premature rupture of membranes, and miscarriage. Due to their “Generally Recognized as Safe” classification and critical role in vaginal health, probiotic lactobacilli have been widely used as an alternative or adjunct to traditional antibiotic therapy for the treatment of vaginal infections and restoration of the vaginal microbiome. This review focuses on the significant role of probiotic lactobacilli in the vaginal microenvironment and discusses the use of probiotic lactobacilli in the treatment of female vaginal infections in vitro and in vivo.

Menopausal Changes in the Microbiome-A Review Focused on the Genitourinary Microbiome

A balanced interaction between the host and its microbiome is crucial to health. Research regarding the significance of the gut and vaginal microbiomes in female health is substantial. However, less data regarding the urinary microbiome are available. Interactions between the gut, vaginal, and urinary microbiomes are also currently being researched. Hormone-induced dysbiosis after menopause is believed to have effects on physical changes and health consequences. Postmenopausal changes in the gut microbiome are associated with increased short-chain fatty acids and hydrogen sulfide levels. Increased vaginal pH caused by reduced estrogen alters the vaginal microbiome, resulting in reduced levels of Lactobacillus. Such changes influence the vaginal structure and functions, contributing to the onset of genitourinary syndrome of menopause. A dysbiosis of the urinary microbiome is associated with urgency and urinary incontinence and also related to interstitial cystitis/bladder pain syndrome and neuropathic bladder. As these diseases commonly affect postmenopausal women, hormone-induced changes in the microbiome may play a role. Menopause increases the alpha diversity of the urinary microbiome and lowers the percentage of Lactobacillus in urine, and such changes precede recurrent cystitis. More research regarding the effects of changes in the urinary microbiome due to menopause on urinary tract diseases is needed.

Alterations of Vaginal Microbiota and Chlamydia trachomatis as Crucial Co-Causative Factors in Cervical Cancer Genesis Procured by HPV

Chlamydia trachomatis and human papillomavirus (HPV) are the most common pathogens found in sexually transmitted infections (STIs), and both are known to increase the risk of cervical cancer (CC) and infertility. HPV is extremely common worldwide, and scientists use it to distinguish between low-risk and high-risk genotypes. In addition, HPV transmission can occur via simple contact in the genital area. From 50 to 80% of sexually active individuals become infected with both C. trachomatis and HPV viruses during their lifetime, and up to 50% become infected with an HPV oncogenic genotype. The natural history of this coinfection is strongly conditioned by the balance between the host microbiome and immune condition and the infecting agent. Though the infection often regresses, it tends to persist throughout adult life asymptomatically and silently. The partnership between HPV and C. trachomatis is basically due to their similarities: common transmission routes, reciprocal advantages, and the same risk factors. C. trachomatis is a Gram-negative bacteria, similar to HPV, and an intracellular bacterium, which shows a unique biphasic development that helps the latter continue its steady progression into the host throughout the entire life. Indeed, depending on the individual’s immune condition, the C. trachomatis infection tends to migrate toward the upper genital tract and spread to the uterus, and the fallopian tubes open up a pathway to HPV invasion. In addition, most HPV and C. trachomatis infections related to the female genital tract are facilitated by the decay of the first line of defense in the vaginal environment, which is constituted by a healthy vaginal microbiome that is characterized by a net equilibrium of all its components. Thus, the aim of this paper was to highlight the complexity and fragility of the vaginal microenvironment and accentuate the fundamental role of all elements and systems involved, including the Lactobacillus strains (Lactobacillus gasseri, Lactobacillus jensenii, Lactobacillus crispatus) and the immune–endocrine system, in preserving it from oncogenic mutation. Therefore, age, diet, and genetic predisposition together with an unspecific, persistent low-grade inflammatory state were found to be implicated in a high frequency and severity grade of disease, potentially resulting in pre-cancerous and cancerous cervical lesions.

A Healthy Vaginal Microbiota Remains Stable during Oral Probiotic Supplementation: A Randomised Controlled Trial

The primary objective of this randomised, placebo-controlled, triple-blind study was to assess whether orally consumed Lactobacillus acidophilus La-14 (La-14) and Lacticaseibacillus rhamnosus HN001 (HN001) colonise a healthy human vagina. Furthermore, potential effects on vaginal microbiota and immune markers were explored. Fifty women devoid of vaginal complaints (Nugent score 0-3 and vaginal pH ≤ 4.5) were randomised into a 2-week intervention with either La-14 and HN001 as the verum product or a comparable placebo. Vaginal swab samples were collected at baseline, after one and two weeks of intervention, and after a one-week follow-up, for assessing colonisation of the supplemented lactobacilli, vaginal microbiota, and six specific immune markers. Colonisation of L. acidophilus and L. rhamnosus was not observed above the assay detection limit (5.29 and 5.11 log 10 genomes/swab for L. acidophilus and L. rhamnosus, respectively). Vaginal microbiotas remained stable and predominated by lactobacilli throughout the intervention, and vaginal pH remained optimal (at least 90% of participants in both groups had pH 4.0 or 4.5 throughout the study). Immune markers elafin and human β-defensin 3 (HBD-3) were significantly decreased in the verum group (p = 0.022 and p = 0.028, respectively) but did not correlate with any microbiota changes. Adverse events raised no safety concerns, and no undesired changes in the vaginal microbiota or immune markers were detected.