The Lactobacillus flora in vagina and rectum of fertile and postmenopausal healthy Swedish women

Directional and Strain-Specific Interaction Between Lactobacillus plantarum and Staphylococcus aureus

The interaction between Lactobacillus plantarum and Staphylococcus aureus strains FRI-1169 and MN8, two original isolated strains from menstrual toxic shock syndrome (mTSS) cases, is a key focus for developing non-antibiotic strategies to control S. aureus-related infections. While the antagonistic effects of Lactobacilli species on S. aureus through mechanisms like organic acid and bacteriocin production are known, the molecular dynamics of these interactions remain underexplored. This study employs a proteomic approach to analyze the interactions between L. plantarum WCFS1 and S. aureus strains, FRI-1169 and MN8, during co-culture. We profiled differentially expressed proteins (DEPs) found in the spent media and cytosols of both bacteria, revealing distinct directional and strain-specific responses. The findings demonstrate that L. plantarum exerts a more pronounced effect on S. aureus, with more DEPs and upregulated proteins, while S. aureus showed fewer DEPs and more downregulated proteins. These strain-specific interactions highlight the complex metabolic and regulatory adjustments between these bacterial species. This research provides valuable insights into the molecular mechanisms of Lactobacillus-S. aureus antagonism and underscores the potential of proteomic analysis as a powerful tool for studying bacterial dynamics in co-culture systems.

Importance of Lactobacilli for Human Health

As an extraordinarily diverse group of bacteria, lactobacilli are now classified into several genera, many of which still include "Lactobacillus" in their names. Despite their names, this group of lactic acid bacteria comprises microorganisms that are crucial for human health, especially during the early development of the human microbiota and immune system. The interactions between lactobacilli and components of the mucosal immunity lead to its shaping and development, which is possibly considered a prime mover in the advancement of the human immune system. Although much of the evidence backing the pivotal role of lactobacilli in maintaining human health comes from studies on probiotics aiming to elucidate the mechanisms of their functional activities and studies on mucosal immunity in germ-free mice, it is justifiable to extend observations on the properties of the individual probiotic Lactobacillus that are related to health benefits onto other strains sharing common characteristics of the species. In this review, we will discuss the acquisition, presence, and functions of lactobacilli in different human microbiota throughout their whole life, including those arising in the amnion and their interactions with mucosal and immune cells. Examples of immune system modulation by probiotic lactobacilli include their colonic competition for available nutrients, interference with colonization sites, competition for binding sites on gut epithelial cells, bacteriocin production, reduction of colonic pH, and nonspecific stimulation of the immune system.

Vaginal microbiomes of breast cancer survivors treated with aromatase inhibitors with and without vulvovaginal symptoms

Genitourinary syndrome of menopause (GSM) is the leading cause of vaginal symptoms in breast cancer survivors treated with aromatase inhibitors. However, there are currently no effective treatment options available for women with a history of breast cancer. Recent research has established that changes in the vaginal microbiome may be linked to GSM. Most studies have assessed the microbiome without accounting for the estrogen status. It remains unknown whether the vaginal microbiome differ among patients with a low estrogenic state with and without vulvovaginal symptoms. To address such research questions, our study compares the vaginal microbiomes among breast cancer survivors treated with aromatase inhibitors with and without vulvovaginal symptoms. A total of 50 breast cancer survivors treated with aromatase inhibitors were recruited, among whom 25 had vulvovaginal symptoms and 25 had no vulvovaginal symptoms. Vaginal swabs were collected. DNA extraction, followed by sequencing of the V3-V4 regions of the 16S ribosomal RNA gene, were performed. Differential abundance analysis was conducted by linear discriminant analysis effect size. Taxonomy assignment, alpha diversity and beta diversity were examined. The relative abundance of genus Sneathia and genus Gardnerella was significantly increased in vulvovaginal symptoms group with no differences in bacterial diversity and richness.

Menopausal status induces vaginal dysbiosis in women with human papillomavirus infection

In this study, we examined the difference in the vaginal microbiota of women infected with human papillomavirus (HPV), according to menopausal status. A total of 75 cervicovaginal swab samples from 38 pre- and 37 postmenopausal women with HPV infection were obtained from the Korean HPV cohort. Vaginal microbiota analysis, including microbial diversity and specific bacterial abundances, was performed using 16S rRNA gene sequencing. The mean age of the pre- and postmenopausal women were 29.5 and 55.8 years, respectively (p < 0.0001). Lactobacillus spp. were predominant in both groups; however, a marked decrease was observed in postmenopausal women compared to premenopausal women (44.3% vs. 74.2%). Various anaerobic bacteria also showed a relatively high abundance in the postmenopausal group; Atopobium vagina and Gardnerella vaginalis significantly increased in postmenopausal women. Interestingly, no significant differences in bacterial richness were observed between the two groups. However, significant differences in beta-diversity were observed using the Bray-Curtis (p = 0.001), Generalized UniFrac (p = 0.002), Jensen-Shannon (p = 0.001), and UniFrac algorithms (p = 0.002). Theres results indicate that postmenopausal women with HPV infection exhibited a higher degree of vaginal dysbiosis than premenopausal women. Further, HPV-infected postmenopausal women had increased vaginal microbial diversity, characterized by an increase in anaerobic bacteria and concomitant depletion of Lactobacillus spp.

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.

Microbiota dynamics, metabolic and immune interactions in the cervicovaginal environment and their role in spontaneous preterm birth

Differences in the cervicovaginal microbiota are associated with spontaneous preterm birth (sPTB), a significant cause of infant morbidity and mortality. Although establishing a direct causal link between cervicovaginal microbiota and sPTB remains challenging, recent advancements in sequencing technologies have facilitated the identification of microbial markers potentially linked to sPTB. Despite variations in findings, a recurring observation suggests that sPTB is associated with a more diverse and less stable vaginal microbiota across pregnancy trimesters. It is hypothesized that sPTB risk is likely to be modified via an intricate host-microbe interactions rather than due to the presence of a single microbial taxon or broad community state. Nonetheless, lactobacilli dominance is generally associated with term outcomes and contributes to a healthy vaginal environment through the production of lactic acid/maintenance of a low pH that excludes other pathogenic microorganisms. Additionally, the innate immunity of the host and metabolic interactions between cervicovaginal microbiota, such as the production of bacteriocins and the use of proteolytic enzymes, exerts a profound influence on microbial populations, activities, and host immune responses. These interplays collectively impact pregnancy outcomes. This review aims to summarize the complexity of cervicovaginal environment and microbiota dynamics, and associations with bacterial vaginosis and sPTB. There is also consideration on how probiotics may mitigate the risk of sPTB and bacterial vaginosis.

Single-Molecule Approach to 16S rRNA for Vaginal Microbiome Signatures in Response to Metronidazole Treatment

Bacterial vaginosis (BV) is the most common infection of the lower reproductive tract among women of reproductive age, characterized by a depletion of health-associated Lactobacillus and an overgrowth of anaerobes. Metronidazole has been recommended as a first-line therapy for treating BV for decades. Although most cases are cured by the treatment, recurrent infections of BV seriously affect women's reproductive health. Until now, limited information on the vaginal microbiota has been explored at the species level. Here, we adopted a single molecular sequencing approach for the 16S rRNA gene, named FLAST (full-length assembly sequencing technology), to analyze the human vaginal microbiota that improved species-level resolution for taxonomy and identified microbiota alterations in the vaginal tract in response to treatment with metronidazole. Appling high-throughput sequencing, we identified 96 and 189 novel full-length 16S rRNA gene sequences in Lactobacillus and Prevotella, respectively, which had not previously been reported in vaginal samples. Moreover, we found that Lactobacillus iners was significantly enriched in the cured group before metronidazole treatment, and that was maintained in a high frequency after the treatment, suggesting an important role for this species in response to metronidazole treatment. Our research also highlights the importance of the single-molecule paradigm for progressing the field of microbiology and applying these insights to better understand the dynamic microbiota during BV treatment. Subsequent novel treatment approaches should be proposed to improve BV treatment outcomes, optimize the vaginal microbiome, and reduce gynecological and obstetric sequelae. IMPORTANCE Bacterial vaginosis (BV) is a common infectious disease of the reproductive tract. Metronidazole treatment, as the first line of treatment, frequently fails at recovery of the microbiome. However, the precise types of Lactobacillus and other bacteria involved in BV remain unclear, and this has resulted in a failure to identify potential markers to predict clinic outcomes. In this study, we adopted a 16S rRNA gene full-length assembly sequencing technology for the taxonomy analysis and evaluation of vaginal microbiota before and after treatment with metronidazole. We additionally identified 96 and 189 novel 16S rRNA gene sequences in Lactobacillus and Prevotella species, respectively, in vaginal samples, which improves our understanding of the vaginal microbiota. Moreover, we found that the abundance of Lactobacillus iners and Prevotella bivia before treatment was associated with a lack of cure. These potential biomarkers will help to facilitate future studies aimed at improving BV treatment outcomes, optimize the vaginal microbiome, and reduce adverse sexual and reproductive outcomes.

The effects of hormone replacement therapy on the microbiomes of postmenopausal women

The sex steroid hormone estrogen plays a number of regulatory roles in female development. During menopause, estrogen synthesis in the ovaries decreases, which results in adverse physiological remodeling and increased risk of disease. Reduced bone density, changes in the community composition profiles of the gut and vaginal microbiome, mood swings and changes in the vaginal environment are to be expected during this time. To alleviate these changes, postmenopausal women can be prescribed hormone replacement therapy (HRT) through the use of exogenous estradiol, often in conjunction with progestin treatment, which re-induces estrogenic action throughout the body. The microbiome and estrogen have a bidirectional, regulatory relationship in the gut, while in the vaginal environment estrogen works indirectly on the microbiome through restoring the vaginal tissue environment that leads to microbial homeostasis. This review discusses what is known about how the gut and vaginal microbiomes of postmenopausal women are responding to HRT, and the potential future of microbe-based therapeutics for symptoms of menopause.

Vaginal microbiota networks as a mechanistic predictor of aerobic vaginitis

Aerobic vaginitis (AV) is a complex vaginal dysbiosis that is thought to be caused by the micro-ecological change of the vaginal microbiota. While most studies have focused on how changes in the abundance of individual microbes are associated with the emergence of AV, we still do not have a complete mechanistic atlas of the microbe-AV link. Network modeling is central to understanding the structure and function of any microbial community assembly. By encapsulating the abundance of microbes as nodes and ecological interactions among microbes as edges, microbial networks can reveal how each microbe functions and how one microbe cooperate or compete with other microbes to mediate the dynamics of microbial communities. However, existing approaches can only estimate either the strength of microbe-microbe link or the direction of this link, failing to capture full topological characteristics of a network, especially from high-dimensional microbial data. We combine allometry scaling law and evolutionary game theory to derive a functional graph theory that can characterize bidirectional, signed, and weighted interaction networks from any data domain. We apply our theory to characterize the causal interdependence between microbial interactions and AV. From functional networks arising from different functional modules, we find that, as the only favorable genus from Firmicutes among all identified genera, the role of Lactobacillus in maintaining vaginal microbial symbiosis is enabled by upregulation from other microbes, rather than through any intrinsic capacity. Among Lactobacillus species, the proportion of L. crispatus to L. iners is positively associated with more healthy acid vaginal ecosystems. In a less healthy alkaline ecosystem, L. crispatus establishes a contradictory relationship with other microbes, leading to population decrease relative to L. iners. We identify topological changes of vaginal microbiota networks when the menstrual cycle of women changes from the follicular to luteal phases. Our network tool provides a mechanistic approach to disentangle the internal workings of the microbiota assembly and predict its causal relationships with human diseases including AV.

Systematic Review and Meta-analysis: Changes of Gut Microbiota before and after Menopause

Objective. To systematically evaluate the differences in intestinal flora before and after menopause. To provide a possible mechanism for perimenopausal syndrome and provide a basis for probiotics as adjuvant therapy. Methods. MEDLINE, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), CNKI, Wanfang, and VIP databases were searched. The included studies were case-control studies. Results. Three case-control studies were included, with a total of 156 people. At the phylum level, there were no differences between premenopausal and postmenopausal women. At the genus level, the relative abundances of A. odoratum and B. cholerae were higher in postmenopausal women than in premenopausal women, with no differences among other genera. The Shannon diversity index increased after menopause, but no differences were found. Only one study found a positive association of estradiol with Gammaproteobacteria and Myxococcales and a negative association with Prevotellaceae. Conclusions. On the basis of previous studies, it was found that there was no significant difference at the phylum level between postmenopausal women and premenopausal women, but Odoribacter and Bilophila increased at the genus level in postmenopausal women. The class of Gammaproteobacteria may be positively correlated with estradiol. Limited by the number of included studies, more high-quality clinical studies are needed for validation.

Semen microbiota in normal and leukocytospermic males

Large numbers of microbes can be present in seminal fluid, and there are differences in the semen microbiota between normal and abnormal semen samples. To evaluate the semen microbiota in patients with leukocytospermia, 87 seminal fluid samples, including 33 samples with a normal seminal leukocyte count and 54 samples with leukocytospermia, were obtained for a cross-sectional analysis. Twenty samples with a normal seminal leukocyte count had normal sperm parameters (Control group), and 13 samples with a normal seminal leukocyte count were from asthenozoospermia patients (Ast group). However, 32 samples with leukocytospermia were from asthenozoospermia patients (LA group), and only 22 samples with leukocytospermia had normal sperm parameters (Leu group). The 16S ribosomal RNA (rRNA) gene sequencing method was used to sequence the microbiota in the seminal fluid, and multiple bioinformatics methods were utilized to analyze the data. Finally, the results showed that the worse sperm parameters were observed in the leukocytospermia-related groups. Semen microbiota analysis found that there was increased alpha diversity in the leukocytospermia-related groups. Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes were the primary phyla in the seminal fluid. Two microbiota profiles, namely, Lactobacillus-enriched and Streptococcus-enriched groups, were identified in this study. The majority of the samples in the groups with a normal seminal leukocyte count could be categorized as Lactobacillus-enriched, whereas the majority of the leukocytospermia samples could be categorized as Streptococcus-enriched. Our study indicated that males with leukocytospermia have worse sperm parameters and a different semen microbiota composition compared to males with a normal seminal leukocyte count.

Changes in the Microbiome of Vaginal Fluid after Menopause in Korean Women

Various microorganisms reside in the human vagina; the vaginal microbiome is closely linked to both vaginal and general health, and for this reason, microbiome studies of the vagina are an area of research. In this study, we analyzed the vaginal microbiome of women before and after menopause to further increase our understanding of the vaginal microbiome and its contribution to general health. We did a 16s rRNA gene-based metagenomic analysis on the vaginal fluids of 11 premenopausal and 19 postmenopausal women in Korea. We confirmed that the taxonomic composition was significantly different between the two groups. In postmenopausal women, species richness was significantly decreased, but species diversity was significantly increased. In particular, among the taxonomic components corresponding to all taxon ranks of the vaginal microbiome, a reduction in Lactobacillus taxa after menopause contributed the most to the difference between the two groups. In addition, we confirmed through metabolic analysis that the lactic-acid concentration was also decreased in the vaginal fluid of women after menopause. Our findings on the correlation between menopause and the microbiome could help diagnose menopause and enhance the prevention and treatment diseases related to menopause.

Microbiomes other than the gut: inflammaging and age-related diseases

During the course of evolution, bacteria have developed an intimate relationship with humans colonizing specific body sites at the interface with the body exterior and invaginations such as nose, mouth, lung, gut, vagina, genito-urinary tract, and skin and thus constituting an integrated meta-organism. The final result has been a mutual adaptation and functional integration which confers significant advantages to humans and bacteria. The immune system of the host co-evolved with the microbiota to develop complex mechanisms to recognize and destroy invading microbes, while preserving its own bacteria. Composition and diversity of the microbiota change according to development and aging and contribute to humans' health and fitness by modulating the immune system response and inflammaging and vice versa. In the last decades, we experienced an explosion of studies on the role of gut microbiota in aging, age-related diseases, and longevity; however, less reports are present on the role of the microbiota at different body sites. In this review, we describe the key steps of the co-evolution between Homo sapiens and microbiome and how this adaptation can impact on immunosenescence and inflammaging. We briefly summarized the role of gut microbiota in aging and longevity while bringing out the involvement of the other microbiota.

Variation of the Vaginal Lactobacillus Microbiome in Cytolytic Vaginosis

OBJECTIVE

This pilot study aimed to evaluate whether different microbial compositions cause symptoms in patients with Lactobacillus overgrowth and to investigate the variation in Lactobacillus microbiome in cytolytic vaginosis (CV).

MATERIALS AND METHODS

Lactobacillus species were identified from the vaginal fluid of 70 healthy women and 79 patients with CV using molecular analysis of the 16S rRNA gene. χ and Fisher exact tests were used to compare the isolated rates of Lactobacillus species between the 2 groups. The capabilities of dominant Lactobacillus strain to produce acid in the 2 groups were analyzed by repeated measures analysis of variance.

RESULTS

The isolation of 2 or more Lactobacillus species per vaginal sampling was significantly less common in the CV group (1.3%) compared with the healthy control (HC) group 12.2% (p = .013). Significant differences in Lactobacillus species were observed between the 2 groups (p < .001). Lactobacillus crispatus was more often found in the CV group (88.7%) than in the HC group (56.4%, p < .001). Compared with that in the HC group, the dominant L. crispatus strain in the CV group tended to produce more acid.

CONCLUSIONS

The CV group carried a less diverse Lactobacillus species, vaginally. Lactobacillus crispatus was common to both CV and HC groups but demonstrated enhanced acid-producing capability in the CV group. The pathogenesis of CV may be based, in part, on an overgrowth of L. crispatus with enhanced acid-producing capability.

The etiology and management of recurrent urinary tract infections in postmenopausal women

Urinary tract infections (UTIs) are one of the most common infections and affect up to 50% of women in their lifetime, with almost half of these women experiencing a recurrence in 6-12 months. Menopause predisposes women to recurrent UTI (rUTI), as normally lower levels of estrogen lead to changes in the urogenital epithelium and subsequently urogenital microbiome. The recently discovered urobiome is now known to have different compositions in both healthy and unhealthy bladders, including a role in the pathophysiology of rUTI, and may be a therapeutic target for prevention and treatment options for rUTI. In postmenopausal women with frequent UTI, the diagnosis of acute UTI should be made using a combination of the symptom assessment and urine diagnostic studies. The choice of UTI antibiotic should include consideration of efficacy, collateral effects, and side-effects. Some women may be candidates for self-start therapy, in which the patient accurately recognizes her UTI symptoms and then starts previously prescribed antibiotics. A large component of the management of women with rUTI is prevention. Urobiome research for bladder health and disease is a young field of investigation with significant potential to improve care for postmenopausal women affected by rUTI through novel, evidence-based prevention and treatment strategies.

Comparison of the Vaginal Microbiomes of Premenopausal and Postmenopausal Women

For decades hormone therapy (HT) has been prescribed to treat the symptoms of menopause, such as vaginal dryness, itching and burning. Here we sought to compare the vaginal microbiomes of postmenopausal women who received low dose estrogen therapy to those of premenopausal and postmenopausal women, and to do so in conjunction with assessing the alleviation of symptoms associated with vaginal atrophy. In this study vaginal swab samples were obtained from 45 women who were classified as either premenopausal, postmenopausal, or postmenopausal and undergoing HT. The vaginal microbiomes of these women were characterized by 16S rRNA gene sequencing and bacterial abundances were quantified by qPCR. We found that the vaginal communities from our cohort could be divided into six clusters (A-F) based on differences in the composition and relative abundances of bacterial taxa. Communities in cluster A were dominated by Lactobacillus crispatus, and those of cluster B were dominated by Gardnerella vaginalis. Communities in cluster C had high proportions of L. iners, while those in cluster D were more even and included several co-dominant taxa. Communities in clusters E and F were dominated by Bifidobacterium and L. gasseri, respectively. The vaginal communities of most postmenopausal women receiving HT (10/15) were dominated by species of lactobacilli and belonged to clusters A, C, and F (P < 0.001). This sharply contrasts with vaginal communities of postmenopausal women without HT, most of which (10/15) were in cluster D, depleted of lactobacilli, and had about 10-fold fewer total bacteria (P < 0.05). The vaginal communities of women in each study group differed in terms of the dominant bacterial species composition and relative abundance. Those of postmenopausal women receiving HT significantly differed from those of postmenopausal women without HT and were most often dominated by species of Lactobacillus. Noteworthy, HT greatly improved vaginal atrophy scores, decreased vaginal pH, and significantly increased bacterial numbers in comparison to postmenopausal women not receiving HT.

Female radical cystectomy patients have a higher risk of surgical site infections

INTRODUCTION

Surgical site infections (SSI) are common after radical cystectomy. The objectives of this study were to evaluate if female sex is associated with postoperative SSI and if experiencing an SSI was associated with subsequent adverse events.

METHODS

This was a historical cohort study of radical cystectomy patients from the American College of Surgeons' National Surgical Quality Improvement Program database between 2006 and 2016. The primary outcome was development of a SSI (superficial, deep, or organ/abdominal space) within 30 days of surgery. Multivariable logistic regression analyses were performed to determine the association between sex and other patient/procedural factors with SSI. Female patients with SSI were also compared to those without SSI to determine risk of subsequent adverse events.

RESULTS

A total of 9,275 radical cystectomy patients met the inclusion criteria. SSI occurred in 1,277(13.7%) patients, 308 (16.4%) females and 969 (13.1%) males (odds ratio = 1.27; 95% confidence interval 1.10-1.47; P = 0.009). Infections were superficial in 150 (8.0%) females versus 410 (5.5%) males (P < 0.0001), deep in 40 (2.1%) females versus 114 (1.5%) males (P = 0.07), and organ/abdominal space in 118 (6.2%) females versus 445 (6.0%) males (P = 0.66). On multivariable analysis, female sex was independently associated with SSI (odds ratio = 1.21 confidence interval 1.01-1.43 P = 0.03). Females who experience SSI had higher probability of developing other complications including wound dehiscence, septic shock, and need for reoperation (all P < 0.05).

CONCLUSIONS

Female sex is an independent risk factor for SSI following radical cystectomy. More detailed study of patient factors, pathogenic microbes, and treatment factors are needed to prescribe the best measures for infection prophylaxis.

Vaginal microbiota and genitourinary menopausal symptoms: a cross-sectional analysis

OBJECTIVE

To examine associations between the composition of the vaginal microbiota and genitourinary menopausal symptoms, serum estrogen, and vaginal glycogen.

METHODS

For this cross-sectional study, 88 women aged 40 to 62 years, enrolled in a hot flash treatment trial, provided vaginal swabs and a blood sample at enrollment. Bacterial communities were characterized using 16S rRNA PCR and deep sequencing targeting the V3-V4 region. Quantities of Lactobacillus crispatus and Lactobacillus iners were measured using qPCR. Self-reported genitourinary symptoms included: presence and severity of individual symptoms and identification of most bothersome symptom. Glycogen was measured fluorometrically in swab eluate. Serum estradiol (E2) and estrone (E1) were measured by liquid chromatography/mass spectrometry. Associations between bacteria, symptoms, glycogen, and serum estrogens were tested by linear regression or Wilcoxon signed-rank test, adjusted for multiple comparisons. Comparisons between groups used Kruskall-Wallis or Fisher's exact test.

RESULTS

Of the 88 women, 33 (38%) had a majority of Lactobacillus species, whereas 58 (66%) had any Lactobacillus detected. Over half (53%) reported at least one vulvovaginal symptom (most commonly dryness), but symptoms were not associated with the presence of Lactobacillus species. Women with Lactobacillus-dominant communities had higher unconjugated serum estrone, but no difference in vaginal glycogen levels, compared with those with non-Lactobacillus-dominant communities. Higher serum E2 and E1 were not associated with either higher vaginal glycogen or detection of individual genera.

CONCLUSIONS

Presence of Lactobacillus-dominant vaginal microbiota was not associated with fewer vulvovaginal symptoms. Serum estrone was higher in women with Lactobacillus dominance, but vaginal-free glycogen was not associated with composition of the vaginal microbiota.

Characterization of vaginal Lactobacillus species by rplK -based multiplex qPCR in Russian women

We describe a multiplex qPCR assay for identification and quantitative assessment of a set of vaginal Lactobacillus species, including L. acidophilus, L. crispatus, L. gasseri, L. helveticus, L. iners, and L. jensenii. The assay extends the previously developed qPCR method for Lactobacillus detection and total quantification based on targeting the rplK gene. Both assays use only single pair of primers and a set of probes combined in three reactions, comprising a vaginal Lactobacillus diagnostic assay panel. The utility of the diagnostic panel was evaluated by analyzing of vaginal swab specimens from 145 patients with different status of vaginal health. Most frequently, only one Lactobacillus species was dominant (68,9%), mostly L. crispatus (18,6%) or L. iners (33,1%), but two or three Lactobacillus species were also being simultaneously detected (24,9%). The diagnostic panel will facilitate investigations of the role of Lactobacillus species in the health of the female reproductive system and promote studies of variability of the vaginal microbiota.

Effects of low dose estrogen therapy on the vaginal microbiomes of women with atrophic vaginitis

Atrophic vaginitis (AV) is common in postmenopausal women, but its causes are not well understood. The symptoms, which include vaginal itching, burning, dryness, irritation, and dyspareunia, can usually be alleviated by low doses of estrogen given orally or locally. Regrettably, the composition of vaginal bacterial communities in women with AV have not been fully characterized and little is known as to how these communities change over time in response to hormonal therapy. In the present intervention study we determined the response of vaginal bacterial communities in postmenopausal women with AV to low-dose estrogen therapy. The changes in community composition in response to hormonal therapy were rapid and typified by significant increases in the relative abundance of Lactobacillus spp. that were mirrored by a decreased relative abundance of Gardnerella. These changes were paralleled by a significant four-fold increase in serum estradiol levels and decreased vaginal pH, as well as nearly a two-fold increase in the Vaginal Maturation Index (VMI). The results suggest that after menopause a vaginal microbiota dominated by species of Lactobacillus may have a beneficial role in the maintenance of health and these findings that could lead to new strategies to protect postmenopausal women from AV.

The vaginal microbiota: what have we learned after a decade of molecular characterization?

We conducted a systematic review of the Medline database (U.S. National Library of Medicine, National Institutes of Health, Bethesda, MD, U.S.A) to determine if consistent molecular vaginal microbiota (VMB) composition patterns can be discerned after a decade of molecular testing, and to evaluate demographic, behavioral and clinical determinants of VMB compositions. Studies were eligible when published between 1 January 2008 and 15 November 2013, and if at least one molecular technique (sequencing, PCR, DNA fingerprinting, or DNA hybridization) was used to characterize the VMB. Sixty three eligible studies were identified. These studies have now conclusively shown that lactobacilli-dominated VMB are associated with a healthy vaginal micro-environment and that bacterial vaginosis (BV) is best described as a polybacterial dysbiosis. The extent of dysbiosis correlates well with Nugent score and vaginal pH but not with the other Amsel criteria. Lactobacillus crispatus is more beneficial than L. iners. Longitudinal studies have shown that a L. crispatus-dominated VMB is more likely to shift to a L. iners-dominated or mixed lactobacilli VMB than to full dysbiosis. Data on VMB determinants are scarce and inconsistent, but dysbiosis is consistently associated with HIV, human papillomavirus (HPV), and Trichomonas vaginalis infection. In contrast, vaginal colonization with Candida spp. is more common in women with a lactobacilli-dominated VMB than in women with dysbiosis. Cervicovaginal mucosal immune responses to molecular VMB compositions have not yet been properly characterized. Molecular techniques have now become more affordable, and we make a case for incorporating them into larger epidemiological studies to address knowledge gaps in etiology and pathogenesis of dysbiosis, associations of different dysbiotic states with clinical outcomes, and to evaluate interventions aimed at restoring and maintaining a lactobacilli-dominated VMB.

Lactobacilli with probiotic potential in the prairie vole (Microtus ochrogaster)

Background

Recent research suggests integration of the intestinal microbiota in gut-brain communication which could lead to new approaches to treat neurological disorders. The highly social prairie voles are an excellent model system to study the effects of environmental factors on social behavior. For future studies on the role of probiotics in ameliorating disorders with social withdrawal symptoms, we report the characterization of intestinal Lactobacillus isolates with probiotic potential from voles.

Methods and results

30 bacterial strains were isolated from the vole intestine and found to be distinct but closely related to Lactobacillus johnsonii using 16S rRNA gene sequencing and Random Amplification of Polymorphic DNA fingerprinting. In vitro characterizations including acid and bile tolerance, antimicrobial effects, antibiotic susceptibility, and adherence to intestinal epithelial cells were performed to assess the probiotic potential of selected strains. Since previous studies revealed that mercury ingestion triggers social deficits in voles, mercury resistance of the probiotic candidates was evaluated which could be an important factor in preventing/treating these behavioral changes.

Conclusions

This study demonstrates that lactobacilli with probiotic potential are present in the vole intestine. The Lactobacillus isolates identified in this study will provide a basis for the investigation of probiotic effects in the vole behavioral model system.

Electronic supplementary material

The online version of this article (doi:10.1186/s13099-015-0082-0) contains supplementary material, which is available to authorized users.

Lactobacillus species as biomarkers and agents that can promote various aspects of vaginal health

The human body is colonized by a vast number of microorganisms collectively referred to as the human microbiota. One of the main microbiota body sites is the female genital tract, commonly dominated by Lactobacillus spp., in approximately 70% of women. Each individual species can constitute approximately 99% of the ribotypes observed in any individual woman. The most frequently isolated species are Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus jensenii and Lactobacillus iners. Residing at the port of entry of bacterial and viral pathogens, the vaginal Lactobacillus species can create a barrier against pathogen invasion since mainly products of their metabolism secreted in the cervicovaginal fluid can play an important role in the inhibition of bacterial and viral infections. Therefore, a Lactobacillus-dominated microbiota appears to be a good biomarker for a healthy vaginal ecosystem. This balance can be rapidly altered during processes such as menstruation, sexual activity, pregnancy and various infections. An abnormal vaginal microbiota is characterized by an increased diversity of microbial species, leading to a condition known as bacterial vaginosis. Information on the vaginal microbiota can be gathered from the analysis of cervicovaginal fluid, by using the Nugent scoring or the Amsel's criteria, or at the molecular level by investigating the number and type of Lactobacillus species. However, when translating this to the clinical setting, it should be noted that the absence of a Lactobacillus-dominated microbiota does not appear to directly imply a diseased condition or dysbiosis. Nevertheless, the widely documented beneficial role of vaginal Lactobacillus species demonstrates the potential of data on the composition and activity of lactobacilli as biomarkers for vaginal health. The substantiation and further validation of such biomarkers will allow the design of better targeted probiotic strategies.

The significance of Lactobacillus crispatus and L. vaginalis for vaginal health and the negative effect of recent sex: a cross-sectional descriptive study across groups of African women

BACKGROUND

Women in sub-Saharan Africa are vulnerable to acquiring HIV infection and reproductive tract infections. Bacterial vaginosis (BV), a disruption of the vaginal microbiota, has been shown to be strongly associated with HIV infection. Risk factors related to potentially protective or harmful microbiota species are not known.

METHODS

We present cross-sectional quantitative polymerase chain reaction data of the Lactobacillus genus, five Lactobacillus species, and three BV-related bacteria (Gardnerella vaginalis, Atopobium vaginae, and Prevotella bivia) together with Escherichia coli and Candida albicans in 426 African women across different groups at risk for HIV. We selected a reference group of adult HIV-negative women at average risk for HIV acquisition and compared species variations in subgroups of adolescents, HIV-negative pregnant women, women engaging in traditional vaginal practices, sex workers and a group of HIV-positive women on combination antiretroviral therapy. We explored the associations between presence and quantity of the bacteria with BV by Nugent score, in relation to several factors of known or theoretical importance.

RESULTS

The presence of species across Kenyan, South African and Rwandan women was remarkably similar and few differences were seen between the two groups of reference women in Kenya and South Africa. The Rwandan sex workers and HIV-positive women had the highest G. vaginalis presence (p = 0.006). Pregnant women had a higher Lactobacillus genus mean log (7.01 genome equivalents (geq)/ml) compared to the reference women (6.08 geq/ml). L. vaginalis (43%) was second to L. iners (81.9%) highly present in women with a normal Nugent score. Recent sexual exposure negatively affected the presence of L. crispatus (<0.001), L. vaginalis (p = 0.001), and Lactobacillus genus (p < 0.001). Having more than one sexual partner in the last three months was associated with an increased prevalence of G. vaginalis (p = 0.044) and L. iners (p = 0.001).

CONCLUSIONS

Although the composition of species across the studied African countries was similar, the presence of protective species i.e. L. crispatus and L. vaginalis in women with a normal Nugent score appeared lower compared to non-African studies. Furthermore, Lactobacillus species were negatively affected by sexual behavioural. Strategies to support protective Lactobacillus species are urgently needed.

TRIAL REGISTRATION

The study is registered at the Trial Registration at the National Health Research Ethics Council South Africa with the number DOH2709103223.

Draft Genome Sequence of Lactobacillus plantarum CMPG5300, a Human Vaginal Isolate

The draft genome of a highly auto-aggregating Lactobacillus plantarum strain isolated from a human vagina is reported. The peculiar phenotype also provides an adhesive and co-aggregative potential with various pathogens, which could be of significance in the vaginal niche. Detailed genome analysis could aid in identifying the adhesins of the strain.

Development of polyether urethane intravaginal rings for the sustained delivery of hydroxychloroquine

Hydroxychloroquine (HCQ) has been shown to demonstrate anti-inflammatory properties and direct anti-HIV activity. In this study, we describe for the first time the fabrication and in vitro evaluation of two types of intravaginal ring (IVR) devices (a surfaced-modified matrix IVR and a reservoir segmental IVR) for achieving sustained delivery (>14 days) of HCQ as a strategy for preventing male-to-female transmission of HIV. Both IVRs were fabricated by hot-melt injection molding. Surface-modified matrix IVRs with polyvinylpyrrolidone or poly(vinyl alcohol) coatings exhibited significantly reduced burst release on the first day (6.45% and 15.72% reduction, respectively). Reservoir IVR segments designed to release lower amounts of HCQ displayed near-zero-order release kinetics with an average release rate of 28.38 μg/mL per day for IVRs loaded with aqueous HCQ and 32.23 μg/mL per day for IVRs loaded with HCQ mixed with a rate-controlling excipient. Stability studies demonstrated that HCQ was stable in coated or noncoated IVRs for 30 days. The IVR segments had no significant effect on cell viability, pro-inflammatory cytokine production, or colony formation of vaginal and ectocervical epithelial cells. Both IVR systems may be suitable for the prevention of HIV transmission and other sexually transmitted infections.

The vaginal microbiota: what have we learned after a decade of molecular characterization?

We conducted a systematic review of the Medline database (U.S. National Library of Medicine, National Institutes of Health, Bethesda, MD, U.S.A) to determine if consistent molecular vaginal microbiota (VMB) composition patterns can be discerned after a decade of molecular testing, and to evaluate demographic, behavioral and clinical determinants of VMB compositions. Studies were eligible when published between 1 January 2008 and 15 November 2013, and if at least one molecular technique (sequencing, PCR, DNA fingerprinting, or DNA hybridization) was used to characterize the VMB. Sixty three eligible studies were identified. These studies have now conclusively shown that lactobacilli-dominated VMB are associated with a healthy vaginal micro-environment and that bacterial vaginosis (BV) is best described as a polybacterial dysbiosis. The extent of dysbiosis correlates well with Nugent score and vaginal pH but not with the other Amsel criteria. Lactobacillus crispatus is more beneficial than L. iners. Longitudinal studies have shown that a L. crispatus-dominated VMB is more likely to shift to a L. iners-dominated or mixed lactobacilli VMB than to full dysbiosis. Data on VMB determinants are scarce and inconsistent, but dysbiosis is consistently associated with HIV, human papillomavirus (HPV), and Trichomonas vaginalis infection. In contrast, vaginal colonization with Candida spp. is more common in women with a lactobacilli-dominated VMB than in women with dysbiosis. Cervicovaginal mucosal immune responses to molecular VMB compositions have not yet been properly characterized. Molecular techniques have now become more affordable, and we make a case for incorporating them into larger epidemiological studies to address knowledge gaps in etiology and pathogenesis of dysbiosis, associations of different dysbiotic states with clinical outcomes, and to evaluate interventions aimed at restoring and maintaining a lactobacilli-dominated VMB.

Rectal Lactobacillus species and their influence on the vaginal microflora: a model of male-to-female transsexual women

INTRODUCTION

Based on Lactobacillus species co-colonizing the vagina and rectum, it has been hypothesized that the rectum may be an important reservoir for vaginal colonization by lactobacilli. There are no data on this issue in male-to-female transsexual women.

AIM

We undertook this observational study to characterize the Lactobacillus species present in the neovagina and rectum of male-to-female transsexual women and to determine the degree of neovaginal-rectal co-colonization in order to gain a better understanding of the potential role of the gut as a reservoir for genital lactobacilli.

METHODS

Sixty-one male-to-female transsexual women with penile skin lined neovagina without clinical signs of infection were recruited on an ongoing basis from among male-to-female transsexual outpatients. Neovaginal and rectal smears were taken for molecular Lactobacillus species profiling by denaturing gradient gel electrophoresis (PCR-DGGE).

MAIN OUTCOME MEASURES

Matching Lactobacillus species between neovagina and rectum.

RESULTS

Forty-three of the 61 male-to-female transsexual women (70.5%) simultaneously harbored the same lactobacilli in both the neovagina and rectum. We found 276 neovaginal and 258 rectal DGGE bands representing 11 Lactobacillus species, with 201 matches of the same Lactobacillus species in neovagina and rectum. 37 of the 61 women (61%) had two or more matching Lactobacillus species.

CONCLUSION

These data support the hypothesis that the rectum may play an important role as source of Lactobacillus species that colonies neovagina of male-to-female transsexual women. In view of the specific anatomical circumstances of the study population, these findings may be extended to the general population of women.

The effects of chronic binge alcohol on the genital microenvironment of simian immunodeficiency virus-infected female rhesus macaques

Alcohol abuse is a widespread problem among those at risk for and living with HIV and can impact transmission and disease progression. In this study we sought to use the simian immunodeficiency virus (SIV)-macaque model to evaluate the immunological and virological changes in the genital microenvironment of females exposed to chronic alcohol. Female rhesus macaques were treated with alcohol (n=6) or isocaloric sucrose (n=6) for 3 months and then inoculated with SIVmac251. To assess the effects of chronic alcohol on SIV disease and the genital microenvironment, we quantified plasma and genital SIV levels, measured inflammatory cells in genital fluids, and characterized microbial flora by gram stains over 10 weeks post-SIV infection. Following 3 months of alcohol/sucrose treatment, significant differences were observed in the vaginal microenvironment of alcohol-treated animals as compared to controls. Microbial flora of alcohol-treated animals had decreased levels of lactobacillus morphotypes and increased levels of gram-positive cocci relative to sucrose controls. Alcohol-treated animals were also more likely to have white blood cells in vaginal fluids prior to SIV inoculation, which persisted through viral set point. Similar levels of cell-free SIV were observed in plasma and vaginal fluids of both groups, but alcohol-treated animals had a higher incidence and levels of cell-associated SIV shed in vaginal secretions. Chronic alcohol treatment negatively impacts the genital microenvironment prior to and over the course of SIV infection and may increase the risk of genital virus shedding and transmission.

Hormonal contraception decreases bacterial vaginosis but oral contraception may increase candidiasis: implications for HIV transmission

OBJECTIVE

A 2012 WHO consultation concluded that combined oral contraception (COC) does not increase HIV acquisition in women, but the evidence for depot medroxyprogesterone acetate (DMPA) is conflicting. We evaluated the effect of COC and DMPA use on the vaginal microbiome because current evidence suggests that any deviation from a 'healthy' vaginal microbiome increases women's susceptibility to HIV.

METHODS

We conducted a systematic review and reanalysed the Hormonal Contraception and HIV Acquisition (HC-HIV) study. Vaginal microbiome outcomes included bacterial vaginosis by Nugent scoring, vaginal candidiasis by culture or KOH wet mount and microbiome compositions as characterized by molecular techniques.

RESULTS

Our review of 36 eligible studies found that COC and DMPA use reduce bacterial vaginosis by 10-20 and 18-30%, respectively. The HC-HIV data showed that COC and DMPA use also reduce intermediate microbiota (Nugent score of 4-6) by 11% each. In contrast, COC use (but not DMPA use) may increase vaginal candidiasis. Molecular vaginal microbiome studies (n=4) confirm that high oestrogen levels favour a vaginal microbiome composition dominated by 'healthy' Lactobacillus species; the effects of progesterone are less clear and not well studied.

CONCLUSION

DMPA use does not increase HIV risk by increasing bacterial vaginosis or vaginal candidiasis. COC use may predispose for vaginal candidiasis, but is not believed to be associated with increased HIV acquisition. However, the potential role of Candida species, and vaginal microbiome imbalances other than bacterial vaginosis or Candida species, in HIV transmission cannot yet be ruled out. Further in-depth molecular studies are needed.

The highly autoaggregative and adhesive phenotype of the vaginal Lactobacillus plantarum strain CMPG5300 is sortase dependent

Lactobacilli are important for the maintenance of a healthy ecosystem in the human vagina. Various mechanisms are postulated but so far are poorly substantiated by molecular studies, such as mutant analysis. Bacterial autoaggregation is an interesting phenomenon that can promote adhesion to host cells and displacement of pathogens. In this study, we report on the identification of a human vaginal isolate, Lactobacillus plantarum strain CMPG5300, which shows high autoaggregative and adhesive capacity. To investigate the importance of sortase-dependent proteins (SDPs) in these phenotypes, a gene deletion mutant was constructed for srtA, the gene encoding the housekeeping sortase that covalently anchors these SDPs to the cell surface. This mutant lost the capacity to autoaggregate, showed a decrease in adhesion to vaginal epithelial cells, and lost biofilm-forming capacity under the conditions tested. These results indicate that the housekeeping sortase SrtA of CMPG5300 is a key determinant of the peculiar surface properties of this vaginal Lactobacillus strain.

Differences in the vaginal lactobacilli of postmenopausal women and influence of rectal lactobacilli

OBJECTIVE

This study was undertaken to characterize the Lactobacillus spp. dominating the vaginal microbiota of healthy postmenopausal women and to determine the possible influence of rectal lactobacilli.

METHODS

Sixty postmenopausal women aged 55-65 years without clinical signs of vaginal infection not receiving hormone replacement therapy were included in this cross-sectional observational study. Based on Gram-stained smears, 30 women with a normal vaginal flora (Nugent score 0) were included in Group 1, and 30 women with an intermediate vaginal flora characterized by an absence of vaginal lactobacilli (Nugent score 4) were included in Group 2. Vaginal and rectal smears were taken for molecular lactobacillus profiling using polymerase chain reaction and denaturing gradient gel electrophoresis. Diversity of vaginal and rectal lactobacilli in postmenopausal women was the main outcome measure.

RESULTS

We noticed a minor interference of gut lactic acid bacteria on a normal vaginal microflora dominated by lactobacilli strains of the L. delbrueckii group. When the normal vaginal microflora is disturbed by depletion of lactobacilli, the gut may function as a reservoir for lactobacilli of the L. casei group, which then colonize the vagina.

CONCLUSION

Our data indicate that rectal lactobacilli may affect the vaginal flora of postmenopausal women in the case of lactobacillary absence and help to maintain a normal vaginal microbiota.

Testing of viscous anti-HIV microbicides using Lactobacillus

The development of topical microbicides for intravaginal use to prevent HIV infection requires that the drugs and formulated products be nontoxic to the endogenous vaginal Lactobacillus. In 30min exposure tests we found dapivirine, tenofovir and UC781 (reverse transcriptase inhibitor anti-HIV drugs) as pure drugs or formulated as film or gel products were not deleterious to Lactobacillus species; however, PSC-RANTES (a synthetic CCR5 antagonist) killed 2 strains of Lactobacillus jensenii. To demonstrate the toxicity of formulated products a new assay was developed for use with viscous and non-viscous samples that we have termed the Lactobacillus toxicity test. We found that the vortex mixing of vaginal Lactobacillus species can lead to reductions in bacterial viability. Lactobacillus can survive briefly, about 2s, but viability declines with increased vortex mixing. The addition of heat inactivated serum or bovine serum albumin, but not glycerol, prevented the decrease in bacterial viability. Bacillus atrophaeus spores also demonstrated loss of viability upon extended mixing. We observed that many of the excipients used in film formulation and the films themselves also afford protection from the killing during vortex mixing. This method is of relevance for toxicity for cidal activities of viscous products.

Characterization of vaginal lactobacilli in women after kidney transplantation

Limited number of publications described vaginal microflora after kidney transplantation. Our PubMed search revealed only 18 publications including words "vaginal bacteria & kidney transplant" in the period of 1978-2011. The aim of this study was to characterize lactobacilli isolated from vaginal swabs of women after kidney transplantation, compared with healthy women. Eighteen renal transplant recipients (mean age 36.1) and 20 healthy women (mean age 36.0) were evaluated. Lactobacilli were cultured on MRS and Columbia blood agars. Biochemical identification with API 50 CHL (bioMerieux, Marcy L'Etoile, France) and multiplex PCR according to Song et al. was performed. Lactobacilli were tested for production of H(2)O(2). Minimal inhibitory concentrations (MICs) of selected antimicrobial agents were determined with E-tests (bioMerieux, Marcy L'Etoile, France) and interpreted with CLSI and EUCAST criteria. No bacterial vaginosis was found among studied women. Two strains of group I were identified as Lactobacillus delbrueckii; 18 strains as Lactobacillus gasseri and 15 strains as Lactobacillus crispatus. Only 3 strains from group II were not identified by species-specific mPCR. Group IV was represented with 2 unidentified strains. Vaginal lactobacilli isolated from healthy women represented more homogenous group compared with heterogenous renal transplant recipients. Biochemical identification of lactobacilli by API 50 CHL kits was concordant with mPCR results only in 7 cases (17.5%), all 7 strains were identified as L. crispatus. Majority (93%) of lactobacilli were H(2)O(2) producers. All isolated lactobacilli (100%) demonstrated high resistance to metronidazole (MIC > 256 μg/ml). Only 2 strains resistant to vancomycin (MICs: 32 and 256 μg/ml respectively), in the study and control group, and one to moxifloxacin (MIC = 32 μg/ml), were found. Resistance to metronidazole and vancomycin was concordant in CLSI and EUCAST (2010) criteria. Although significant differences between lactobacilli isolated from vaginas of kidney transplant and healthy women were not demonstrated, we demonstrated strains resistant to metronidazole, vancomycin and moxifloxacin in groups of examined women. Our study was performed on a small group of kidney transplant recipients and further more detailed molecular studies on a larger group of patients are required to confirm our results.