Vaginal microbiota and the potential of Lactobacillus derivatives in maintaining vaginal health

Moderate concentration of Lactobacillus metabolites does not adversely affect mouse sperm

Many couples in contemporary societies suffer from infertility of unexplained origins (idiopathic). A promising treatment strategy within this context involves the administration to women of preparations containing lactic acid bacteria (Lactobacillus) and/or their metabolites. Recent investigations underscore the role of lactobacilli in sustaining female fertility and enhancing the effectiveness of assisted reproductive techniques. There have also been reports describing the effect of lactobacilli on sperm functions, but our knowledge in this domain remains uncertain. In this study, the effect of supernatant from Lactobacillus rhamnosus culture on mouse sperm viability and motility was tested. The protective properties of lactobacilli metabolites against hydrogen peroxide-induced DNA damage were also verified. It was shown that the metabolites have no effect on viability, motility, and genome integrity of spermatozoa, but in excessive concentrations they become toxic. The obtained results imply that probiotic and/or postbiotic preparations taken by women should not adversely affect the sperm of their partners, provided the dose is correctly selected.

Role and mechanism of Lactobacillus casei in the modulation of alcohol preference in mice

BACKGROUND

Prolonged alcohol consumption may lead to gastrointestinal tract dysfunction and cause abnormalities in the associated nervous system activity, thereby increasing the body's craving for alcohol. Lactobacillus casei is a probiotic that has been shown to reduce the incidence of alcohol-related diseases. However, it is unclear whether Lactobacillus casei can delay the development of alcohol dependence.

METHODS

The chronic intermittent active drinking method was used to establish a mouse alcohol dependence model. The mice were randomly divided into 4 treatment groups, as follows: (1) Control group: two bottles of distilled water alternately, 0.2 mL/d saline gavage. (2) Alcohol group: alternating water and alcohol, 0.2 mL/d saline gavage. (3) Low group: alternating water and alcohol, 0.2 mL/d 1 × 108CFU of Lactobacillus casei by gavage. (4) High group: alternating water and alcohol, 0.2 mL/d 1 × 109CFU of Lactobacillus casei by gavage. The daily water consumption (mL), alcohol consumption (mL) and body weight of each mouse were recorded. After that, pathological changes in the intestines, brain tissues and serum of the experimental animals were detected, while changes in the intestinal flora of the mice were analysed by 16S rRNA sequencing.

RESULTS

The Lactobacillus casei intervention did not produce a significant effect on body weight in alcohol-exposed mice (P>0.05), but significantly reduced alcohol preference in alcohol-exposed mice (P<0.05). Subsequent analyses showed that Lactobacillus casei significantly ameliorated intestinal, brain tissue, and systemic inflammatory responses in alcohol-exposed mice (P<0.05). 16S rRNA sequencing showed that alcohol-exposed mice treated with Lactobacillus casei exhibited a richer composition of intestinal microorganisms, such as f__Rikenellaceae, g__Alistipes_A_871400, and g__Bacteroides_H genera showed relative enrichment in the High group.

CONCLUSION

By showing that Lactobacillus casei slows down alcohol preference and alleviates gut and brain tissue inflammation in alcohol-exposed mice, our findings provide a possible strategy: Lactobacillus casei may be able to serve as a potential target for the prevention and treatment of alcohol dependence.

Camptothecin multifunctional nanoparticles effectively achieve a balance between the efficacy of breast cancer treatment and the preservation of intestinal homeostasis

Camptothecin (CPT) exhibits potent antitumor activity; however, its clinical application is limited by significant gastrointestinal adverse effects (GAEs). Although the severity of GAEs associated with CPT derivatives has decreased, the incidence rate of these adverse effects has remained high. CPT multifunctional nanoparticles (PCRHNs) have the potential to increase the efficacy of CPT while reducing side effects in major target organs; however, the impact of PCRHNs on the GAEs from CPT remains uncertain. Here, we investigated the therapeutic effects of PCRHNs and different doses of CPT and examined their impacts on the intestinal barrier and the intestinal microbiota. We found that the therapeutic efficacy of PCRHNs + Laser treatment was superior to that of high-dose CPT, and PCRHNs + Laser treatment also provided greater benefits by helping maintain intestinal barrier integrity, intestinal microbiota diversity, and intestinal microbiota abundance. In summary, compared to high-dose CPT treatment, PCRHNs + Laser treatment can effectively balance therapeutic effects and GAEs. A high dose of CPT promotes the enrichment of the pathogenic bacteria Escherichia-Shigella, which may be attributed to diarrhea caused by CPT, thus leading to a reduction in microbial burden; additionally, Escherichia-Shigella rapidly grows and occupies niches previously occupied by other bacteria that are lost due to diarrhea. PCRHNs + Laser treatment increased the abundance of Lactobacillus (probiotics), possibly due to the photothermal effect of the PCRHNs. This effect increased catalase activity, thus facilitating the conversion of hydrogen peroxide into oxygen within tumors and increasing oxygen levels in the body, which is conducive to the growth of facultative anaerobic bacteria.

Cervicovaginal microbiome, high-risk HPV infection and cervical cancer: Mechanisms and therapeutic potential

The microbiota in the female genital tract is an intricate assembly of diverse aerobic, anaerobic, and microaerophilic microorganisms, which share the space within the reproductive tract and engage in complex interactions. Microbiome dysbiosis may disrupt the symbiotic relationship between the host and microorganisms and play a pivotal role in the pathogenesis of various diseases, including its involvement in the establishment of human papillomavirus (HPV)-associated cervical cancer (CC). Interventions to restore microbiota homeostasis (e.g., probiotics) and bacterial-vector HPV therapeutic vaccines have been reported to be potentially effective in clearing HPV infection and ameliorating cytological abnormalities. In this review, we place emphasis on elucidating the alterations within the cervical-vaginal microbiota as well as the intratumoral microbiota in the context of high-risk HPV (HR-HPV) infection and its subsequent progression to cervical intraepithelial neoplasia/CC. Furthermore, we explore the mechanisms by which these microbial communities exert potential pathogenic or protective effects, including modulating genital inflammation and immune responses, affecting HR-HPV oncogene expression and oncoprotein production, regulating oxidative stress and deoxyribonucleic acid (DNA) damage, and inducing metabolic rewiring. Lastly, we summarize the latest evidence in human trials regarding the efficacy of probiotics, prebiotics and probiotic-vector HPV therapeutic vaccines. This review aims to foster a deeper understanding of the role of the microbiota in HR-HPV infection-related cervix cancer development, and further provide a theoretical basis for the development of preventive and therapeutic strategies based on microbial modulation.

The association between lifestyle factors and the composition of the vaginal microbiota: a review

PURPOSE

The vaginal microbiota offers valuable insights into women's sexual health and the risk of developing sexually transmitted infections (STIs) and bacterial vaginosis. Despite the public health implications of changes in the vaginal environment, existing data on this topic remain sparse.

METHODS

Following the PRISMA statement guidelines, we consulted five bibliographic databases, focusing on five main daily habits and behaviors. We included only studies published up to October 2023, investigating the influence of personal hygiene, sexual behaviors, hormonal contraception, smoking, alcohol consumption, and psychosocial stress on the vaginal microbiota using next-generation sequencing.

RESULTS

Based on our inclusion criteria, we incorporated 37 studies into this review. Hormonal contraception and personal hygiene were found to promote eubiosis of the vaginal microbiota. In contrast, sexual behaviors, smoking, alcohol consumption, and psychosocial stress were associated with an increased susceptibility to bacterial vaginosis, STIs, and severe pelvic inflammatory diseases due to a modified vaginal microbiota. Black ethnicity emerged as a confounding factor, with this population showing unstable vaginal microbiota. Oral contraception and a stable male sexual partner were found to favor Lactobacillus colonization, acting as a protective factor. Conversely, non-hormonal contraception and unprotected or non-penile/vaginal sexual activity increased the incidence of vaginal inflammation and bacterial vaginosis by disturbing the vaginal microbiota and reducing Lactobacillus abundance.

CONCLUSION

Daily habits and lifestyle can influence the composition of the vaginal microbiota, thereby affecting vaginal health. Disturbances in the vaginal microbiota could be associated factors for STIs and vaginosis. Therefore, prioritizing more appropriate management of the vaginal microbiota is crucial.

Exploring nature's battlefield: organismic interactions in the discovery of bioactive natural products

Covering: up to March 2024.Microbial natural products have historically been a cornerstone for the discovery of therapeutic agents. Advanced (meta)genome sequencing technologies have revealed that microbes harbor far greater biosynthetic capabilities than previously anticipated. However, despite the application of CRISPR/Cas-based gene editing and high-throughput technologies to activate silent biosynthetic gene clusters, the rapid identification of new natural products has not led to a proportional increase in the discovery rate of lead compounds or drugs. A crucial issue in this gap may be insufficient knowledge about the inherent biological and physiological functions of microbial natural products. Addressing this gap necessitates recognizing that the generation of functional natural products is deeply rooted in the interactions between the producing microbes and other (micro)organisms within their ecological contexts, an understanding that is essential for harnessing their potential therapeutic benefits. In this review, we highlight the discovery of functional microbial natural products from diverse niches, including those associated with humans, nematodes, insects, fungi, protozoa, plants, and marine animals. Many of these findings result from an organismic-interaction-guided strategy using multi-omic approaches. The current importance of this topic lies in its potential to advance drug discovery in an era marked by increasing antimicrobial resistance.

Prevotella timonensis degrades the vaginal epithelial glycocalyx through high fucosidase and sialidase activities

Bacterial vaginosis (BV) is a polymicrobial infection of the female reproductive tract. BV is characterized by replacement of health-associated Lactobacillus species by diverse anerobic bacteria, including the well-known Gardnerella vaginalis. Prevotella timonensis, and Prevotella bivia are anerobes that are found in a significant number of BV patients, but their contributions to the disease process remain to be determined. Defining characteristics of anerobic overgrowth in BV are adherence to the mucosal surface and the increased activity of mucin-degrading enzymes such as sialidases in vaginal secretions. We demonstrate that P. timonensis, but not P. bivia, strongly adheres to vaginal and endocervical cells to a similar level as G. vaginalis but did not elicit a comparable proinflammatory epithelial response. The P. timonensis genome uniquely encodes a large set of mucus-degrading enzymes, including four putative fucosidases and two putative sialidases, PtNanH1 and PtNanH2. Enzyme assays demonstrated that fucosidase and sialidase activities in P. timonensis cell-bound and secreted fractions were significantly higher than for other vaginal anerobes. In infection assays, P. timonensis efficiently removed fucose and α2,3- and α2,6-linked sialic acid moieties from the epithelial glycocalyx. Recombinantly expressed P. timonensis NanH1 and NanH2 cleaved α2,3 and α2,6-linked sialic acids from the epithelial surface, and sialic acid removal by P. timonensis could be blocked using inhibitors. This study demonstrates that P. timonensis has distinct virulence-related properties that include initial adhesion and a high capacity for mucin degradation at the vaginal epithelial mucosal surface. Our results underline the importance of understanding the role of different anerobic bacteria in BV.

IMPORTANCE

Bacterial vaginosis (BV) is a common vaginal infection that affects a significant proportion of women and is associated with reduced fertility and increased risk of secondary infections. Gardnerella vaginalis is the most well-known BV-associated bacterium, but Prevotella species including P. timonensis and P. bivia may also play an important role. We showed that, similar to G. vaginalis, P. timonensis adhered well to the vaginal epithelium, suggesting that both bacteria could be important in the first stage of infection. Compared to the other bacteria, P. timonensis was unique in efficiently removing the protective mucin sugars that cover the vaginal epithelium. These results underscore that vaginal bacteria play different roles in the initiation and development of BV.

Population-specific differences in the human microbiome: Factors defining the diversity

Differences in microbial communities at different body habitats define the microbiome composition of the human body. The gut, oral, skin vaginal fluid and tissue microbiome, are pivotal for human development and immune response and cross talk between these microbiomes is evident. Population studies reveal that various factors, such as host genetics, diet, lifestyle, aging, and geographical location are strongly associated with population-specific microbiome differences. The present review discusses the factors that shape microbiome diversity in humans, and microbiome differences in African, Asian and Caucasian populations. Gut microbiome studies show that microbial species Bacteroides is commonly found in individuals living in Western countries (Caucasian populations), while Prevotella is prevalent in non-Western countries (African and Asian populations). This association is mainly due to the high carbohydrate, high fat diet in western countries in contrast to high fibre, low fat diets in African/ Asian regions. Majority of the microbiome studies focus on the bacteriome component; however, interesting findings reveal that increased bacteriophage richness, which makes up the virome component, correlates with decreased bacterial diversity, and causes microbiome dysbiosis. An increase of Caudovirales (bacteriophages) is associated with a decrease in enteric bacteria in inflammatory bowel diseases. Future microbiome studies should evaluate the interrelation between bacteriome and virome to fully understand their significance in the pathogenesis and progression of human diseases. With ethnic health disparities becoming increasingly apparent, studies need to emphasize on the association of population-specific microbiome differences and human diseases, to develop microbiome-based therapeutics. Additionally, targeted phage therapy is emerging as an attractive alternative to antibiotics for bacterial infections. With rapid rise in microbiome research, focus should be on standardizing protocols, advanced bioinformatics tools, and reducing sequencing platform related biases. Ultimately, integration of multi-omics data (genomics, transcriptomics, proteomics and metabolomics) will lead to precision models for personalized microbiome therapeutics advancement.

Linking reproductive tract microbiota to premature ovarian insufficiency: Pathophysiological mechanisms and therapies

Over the past decade, research on the human microbiota has become a hot topic. Among them, the female reproductive tract (FRT) also has a specific microbiota that maintains the body's health and dynamic balance, especially in the reproductive aspect. When the FRT ecosystem is dysregulated, changes in immune and metabolic signals can lead to pathological and physiological changes such as chronic inflammation, epithelial barrier disruption, changes in cell proliferation and apoptosis, and dysregulation of angiogenesis and metabolism, thereby causing disruption of the female endocrine system. Premature ovarian insufficiency (POI), a clinical syndrome of ovarian dysfunction, is primarily influenced by immune, genetic, and environmental factors. New evidence suggests that dysbiosis of the FRT microbiota and/or the presence of specific bacteria may contribute to the occurrence and progression of POI. This influence occurs through both direct and indirect mechanisms, including the regulation of estrogen metabolism. The use of probiotics or microbiota transplantation to regulate the microbiome has also been proven to be beneficial in improving ovarian function and the quality of life in women with premature aging. This article provides an overview of the interrelationships and roles between the FRT microbiome and POI in recent years, to fully understand the risk factors affecting female reproductive health, and to offer insights for the future diagnosis, treatment, and application of the FRT microbiome in POI patients.

Microbiome-Mucosal Immunity Nexus: Driving Forces in Respiratory Disease Progression

The importance of the complex interplay between the microbiome and mucosal immunity, particularly within the respiratory tract, has gained significant attention due to its potential implications for the severity and progression of lung diseases. Therefore, this review summarizes the specific interactions through which the respiratory tract-specific microbiome influences mucosal immunity and ultimately impacts respiratory health. Furthermore, we discuss how the microbiome affects mucosal immunity, considering tissue-specific variations, and its capacity in respiratory diseases containing asthma, chronic obstructive pulmonary disease, and lung cancer. Additionally, we investigate the external factors which affect the relationship between respiratory microbiome and mucosal immune responses. By exploring these intricate interactions, this review provides valuable insights into the potential for microbiome-based interventions to modulate mucosal immunity and alleviate the severity of respiratory 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.

Heat-Killed Lactobacillus acidophilus Promotes Growth by Modulating the Gut Microbiota Composition and Fecal Metabolites of Piglets

Probiotics can improve animal growth performance and intestinal health. However, understanding the effects of paraprobiotics on the growth performance and gut microbiota of piglets and how the paraprobiotics exert their impact are still limited. The present study was conducted to investigate the effects of heat-killed Lactobacillus acidophilus IFFI 6005 supplementation on the growth performance, intestinal microbiota, and fecal metabolites of piglets. First, a feed-additive sample of heat-killed Lactobacillus acidophilus IFFI 6005 was prepared by culture. Second, 96 (initial BW = 14.38 ± 0.67 kg, weaning age of 40 days) healthy piglets were selected and randomized into four treatment groups. Each treatment group consisted of three replicates (n = 8). Pigs were fed a basal diet (NC), basal diet plus antibiotics (PC), basal diet plus Lactobacillus acidophilus IFFI 6005 at 600 g/t (LA, 1.0 × 1010 cfu/g), and basal diet plus heat-killed Lactobacillus acidophilus IFFI 6005 at 600 g/t (HKLA), respectively; the trial lasted for 30 days. The results showed that the ratios of feed to gain (F:G) and diarrhea rate of both the HKLA and PC groups were significantly lower compared with the NC and LA groups (p < 0.05); however, there was no significant difference between the HKLA and PC group (p > 0.05). In addition, the average daily weight gain (ADG) of the HKLA group was significantly higher (p < 0.05) than that of the other three groups in terms of growth performance. Finally, 16S rRNA sequencing and metabolome analysis based on fecal samples further elaborated that the addition of heat-killed Lactobacillus acidophilus IFFI 6005 to the feed improved the intestinal microbial diversity and abundance (p < 0.05) and reduced the abundance of pathogenic bacteria (p < 0.05), but it did not affect the abundance of Lactobacillus (p > 0.05). Through the comparison of microbial abundance and metabolite content between the two groups (NC_vs_HKLA), the largest differences were found in six microorganisms and 10 metabolites in the intestine (p < 0.05). These differential metabolites were involved in the digestion, absorption and utilization of protein and starch, as well as in oxidative stress. In summary, addition of heat-killed Lactobacillus acidophilus IFFI 6005 as a new feed additive in piglets has beneficial effects on the growth performance, intestinal bacteria and metabolites, and can be used as an alternative to antibiotics.

Protective Mechanisms of Vaginal Lactobacilli against Sexually Transmitted Viral Infections

The healthy cervicovaginal microbiota is dominated by various Lactobacillus species, which support a condition of eubiosis. Among their many functions, vaginal lactobacilli contribute to the maintenance of an acidic pH, produce antimicrobial compounds, and modulate the host immune response to protect against vaginal bacterial and fungal infections. Increasing evidence suggests that these beneficial bacteria may also confer protection against sexually transmitted infections (STIs) caused by viruses such as human papillomavirus (HPV), human immunodeficiency virus (HIV) and herpes simplex virus (HSV). Viral STIs pose a substantial public health burden globally, causing a range of infectious diseases with potentially severe consequences. Understanding the molecular mechanisms by which lactobacilli exert their protective effects against viral STIs is paramount for the development of novel preventive and therapeutic strategies. This review aims to provide more recent insights into the intricate interactions between lactobacilli and viral STIs, exploring their impact on the vaginal microenvironment, host immune response, viral infectivity and pathogenesis, and highlighting their potential implications for public health interventions and clinical management strategies.

Characterization of bovine vaginal microbiota using 16S rRNA sequencing: associations with host fertility, longevity, health, and production

Due to their potential impact on the host's phenotype, organ-specific microbiotas are receiving increasing attention in several animal species, including cattle. Specifically, the vaginal microbiota of ruminants is attracting growing interest, due to its predicted critical role on cows' reproductive functions in livestock contexts. Notably, fertility disorders represent a leading cause for culling, and additional research would help to fill relevant knowledge gaps. In the present study, we aimed to characterize the vaginal microbiota of a large cohort of 1171 female dairy cattle from 19 commercial herds in Northern France. Vaginal samples were collected using a swab and the composition of the microbiota was determined through 16S rRNA sequencing targeting the V3-V4 hypervariable regions. Initial analyses allowed us to define the core bacterial vaginal microbiota, comprising all the taxa observed in more than 90% of the animals. Consequently, four phyla, 16 families, 14 genera and a single amplicon sequence variant (ASV) met the criteria, suggesting a high diversity of bacterial vaginal microbiota within the studied population. This variability was partially attributed to various environmental factors such as the herd, sampling season, parity, and lactation stage. Next, we identified numerous significant associations between the diversity and composition of the vaginal microbiota and several traits related to host's production and reproduction performance, as well as reproductive tract health. Specifically, 169 genera were associated with at least one trait, with 69% of them significantly associated with multiple traits. Among these, the abundances of Negativibacillus and Ruminobacter were positively correlated with the cows' performances (i.e., longevity, production performances). Other genera showed mixed relationships with the phenotypes, such as Leptotrichia being overabundant in cows with improved fertility records and reproductive tract health, but also in cows with lower production levels. Overall, the numerous associations underscored the complex interactions between the vaginal microbiota and its host. Given the large number of samples collected from commercial farms and the diversity of the phenotypes considered, this study marks an initial step towards a better understanding of the intimate relationship between the vaginal microbiota and the dairy cow's phenotypes.

The microbiome effect on the female reproductive performance

The female reproductive function is coordinated by the endocrine system driven by the hypothalamic-pituitary-gonadal (HPG) axis. While not directly part of the female reproductive system, the gut microbiome plays a crucial role in overall health, including reproductive health. The gut microbiome communicates bidirectionally with the brain via the gut-brain axis, influencing stress levels, mood, and hormonal balance, which can impact reproductive health and fertility. In addition to that, the vaginal and uterine microbiome are directly involved with the reproductive success of farm animals, including female fertility and offspring development. In this paper, we summarize some of the effects of bacterial contamination in the female reproductive tract and their association with reproductive performance in farm animals.

Antitumorigenic potential of Lactobacillus-derived extracellular vesicles: p53 succinylation and glycolytic reprogramming in intestinal epithelial cells via SIRT5 modulation

OBJECTIVE

Colorectal cancer progression involves complex cellular mechanisms. This study examines the effects of Lactobacillus plantarum-derived extracellular vesicles (LEVs) on the SIRT5/p53 axis, focusing on glycolytic metabolic reprogramming and abnormal proliferation in intestinal epithelial cells.

METHODS

LEVs were isolated from Lactobacillus plantarum and incubated with Caco-2 cells. Differential gene expression was analyzed through RNA sequencing and compared with TCGA-COAD data. Key target genes and pathways were identified using PPI network and pathway enrichment analysis. Various assays, including RT-qPCR, EdU staining, colony formation, flow cytometry, and Western blotting, were used to assess gene expression, cell proliferation, and metabolic changes. Co-immunoprecipitation confirmed the interaction between SIRT5 and p53, and animal models were employed to validate in vivo effects.

RESULTS

Bioinformatics analysis indicated the SIRT5/p53 axis as a critical pathway in LEVs' modulation of colorectal cancer. LEVs were found to inhibit colorectal cancer cell proliferation and glycolytic metabolism by downregulating SIRT5, influencing p53 desuccinylation. In vivo, LEVs regulated this axis, reducing tumor formation in mice. Clinical sample analysis showed that SIRT5 and p53 succinylation levels correlated with patient prognosis.

CONCLUSION

Lactobacillus-derived extracellular vesicles play a pivotal role in suppressing colonic tumor formation by modulating the SIRT5/p53 axis. This results in decreased glycolytic metabolic reprogramming and reduced proliferation in intestinal epithelial cells.

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.

A multi-kingdom collection of 33,804 reference genomes for the human vaginal microbiome

The human vagina harbours diverse microorganisms-bacteria, viruses and fungi-with profound implications for women's health. Genome-level analysis of the vaginal microbiome across multiple kingdoms remains limited. Here we utilize metagenomic sequencing data and fungal cultivation to establish the Vaginal Microbial Genome Collection (VMGC), comprising 33,804 microbial genomes spanning 786 prokaryotic species, 11 fungal species and 4,263 viral operational taxonomic units. Notably, over 25% of prokaryotic species and 85% of viral operational taxonomic units remain uncultured. This collection significantly enriches genomic diversity, especially for prevalent vaginal pathogens such as BVAB1 (an uncultured bacterial vaginosis-associated bacterium) and Amygdalobacter spp. (BVAB2 and related species). Leveraging VMGC, we characterize functional traits of prokaryotes, notably Saccharofermentanales (an underexplored yet prevalent order), along with prokaryotic and eukaryotic viruses, offering insights into their niche adaptation and potential roles in the vagina. VMGC serves as a valuable resource for studying vaginal microbiota and its impact on vaginal health.

Navigating the Microbial Landscape: Understanding Dysbiosis in Human Genital Tracts and Its Impact on Fertility

Dysbiosis, an imbalance in microbial communities, significantly impacts the health and functionality of the human genital tract, with profound implications for fertility and reproductive health. This review explores the intricate relationship between genital tract microbiota and reproductive outcomes, highlighting the composition and dynamics of these microbial communities in both females and males. In females, the vaginal microbiota, primarily dominated by Lactobacillus species, is essential for maintaining a healthy vaginal environment, preventing infections, and supporting reproductive functions. In males, the genital microbiota influences sperm quality and reproductive health. Dysbiosis in the genital tract, manifesting as bacterial vaginosis, yeast infections, urethritis, or prostatitis, disrupts these microbial communities, leading to adverse reproductive outcomes such as infertility, pregnancy, and increased susceptibility to sexually transmitted infections. This review delves into the mechanisms through which dysbiosis affects fertility, including alterations in vaginal pH, mucosal immunity, inflammation, sperm viability, and motility. It also evaluates diagnostic methods, clinical implications, and management strategies, including probiotics, prebiotics, antibiotics, antifungal treatments, lifestyle interventions, and emerging therapeutic approaches. By understanding the microbial landscape of the genital tract and its impact on fertility, this review aims to inform targeted interventions that restore microbial balance and enhance reproductive health, ultimately improving fertility outcomes and the potential for healthy pregnancies.

Anti-inflammatory effects of extracellular vesicles and cell-free supernatant derived from Lactobacillus crispatus strain RIGLD-1 on Helicobacter pylori-induced inflammatory response in gastric epithelial cells in vitro

Helicobacter pylori infection is the major risk factor associated with the development of gastric cancer. Currently, administration of standard antibiotic therapy combined with probiotics and postbiotics has gained significant attention in the management of H. pylori infection. In this work, the immunomodulatory effects of Lactobacillus crispatus-derived extracellular vesicles (EVs) and cell-free supernatant (CFS) were investigated on H. pylori-induced inflammatory response in human gastric adenocarcinoma (AGS) cells. L. crispatus-derived EVs were isolated by ultracentrifugation and physically characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Furthermore, the protein content of L. crispatus-derived EVs was also evaluated by SDS-PAGE. Cell viability of AGS cells exposed to varying concentrations of EVs and CFS was assessed by MTT assay. The mRNA expression of IL-1β, IL-6, IL-8, TNF-α, IL-10, and TGF-ß genes was determined by RT-qPCR. ELISA was used for the measurement of IL-8 production in AGS cells. In addition, EVs (50 μg/mL) and CFS modulated the H. pylori-induced inflammation by downregulating the mRNA expression of IL-1β, IL-6, IL-8, and TNF-α, and upregulating the expression of IL-10, and TGF-ß genes in AGS cells. Furthermore, H. pylori-induced IL-8 production was dramatically decreased after treatment with L. crispatus-derived EVs and CFS. In conclusion, our observation suggests for the first time that EVs released by L. crispatus strain RIGLD-1 and its CFS could be recommended as potential therapeutic agents against H. pylori-triggered inflammation.

Effectiveness of vaginal probiotics Lactobacillus crispatus chen-01 in women with high-risk HPV infection: a prospective controlled pilot study

Female genital tract infection with high-risk human papilloma virus (HR-HPV) has the risk of developing into cervical cancer, and there is still a lack of effective therapeutic strategies. Probiotic intervention is considered as a potential intervention for HR-HPV, while exploration into living probiotic preparations for specific diseases remains limited and insufficient. This prospective controlled pilot study was conducted to observe the effect of intravaginal transplantation of a vaginal isolated natural probiotic strain, Lactobacillus crispatus chen-01, on the clearance of high-risk HPV infection. 100 women with high-risk HPV infection were enrolled and randomly divided into placebo group and probiotic treatment group, which received intravaginal transplantation of L. crispatus chen-01. Cervical exfoliated cells were collected 6 months later for detecting DNA load, typing of HPV, and cytological analysis. Our results showed that vaginal transplantation with L. crispatus chen-01 significantly reduced viral load of HPV, ameliorated HPV clearance rate, and improved vaginal inflammation state without causing obvious adverse reactions. Analysis of 16S rRNA sequencing revealed that L. crispatus chen-01 could effectively reconstitute the vaginal microbiota in women with high-risk HPV, which might be one of the underlying mechanisms of the beneficial effect of L. crispatus chen-01 transplantation. Our results suggested that vaginal transplantation of L. crispatus chen-01 might be a promising treatment for patients with high-risk HPV infection.

Metagenomic profiling uncovers microbiota and antibiotic resistance patterns across human, chicken, pig fecal, and soil environments

The ongoing and progressive evolution of antibiotic resistance presents escalating challenges for the clinical management and prevention of bacterial infections. Understanding the makeup of resistance genomes and accurately quantifying the current abundance of antibiotic resistance genes (ARGs) are crucial for assessing the threat of antimicrobial resistance (AMR) to public health. This comprehensive study investigated the distribution and diversity of bacterial community composition, ARGs, and virulence factors (VFs) across human, chicken, pig fecal, and soil microbiomes in various provinces of China. As a result, multidrug resistance was identified across all samples. Core ARGs primarily related to multidrug, MLS (Macrolides-Lincosamide-Streptogramins), and tetracycline resistance were characterized. A significant correlation between ARGs and bacterial taxa was observed, especially in soil samples. Probiotic strains such as Lactobacillus harbored ARGs, potentially contributing to the dissemination of antibiotic resistance. We screened subsets of ARGs from samples from different sources as indicators to assess the level of ARGs contamination in samples, with high accuracy. These results underline the complex relationship between microbial communities, resistance mechanisms, and environmental factors, emphasizing the importance of continued research and monitoring to better understand these dynamics.

The influence of the vaginal ecosystem on vaginitis, bacterial vaginosis, and sexually transmitted diseases: an epidemiological study and literature review

PURPOSE

This study aimed to demonstrate the correlation between altered balance of the vaginal ecosystem and increased risk of vaginitis, bacterial vaginosis, and sexually transmitted diseases and the association between specific alterations found in fresh bacterioscopic examinations (FBE) and the risk of certain infections.

METHODS

A retrospective, monocentric study was conducted from January 2013 to December 2023. Patients who underwent FBE and vaginal swabs following reported symptoms or suspected syndromic pictures of vulvovaginal infections were included.

RESULTS

Two thousand one hundred ten patients were included and divided into a control group (n = 811, 38.4%) and a pathological group (n = 1299 patients, 61.6%), based on the presence of alterations at the FBE. In the pathological group, 1185 women (91% of positive FBE) had vaginal infections detected through vaginal swabs. The presence of lactobacilli and typical inflammatory cells was detected in 111 (8%) women with pathological FBE and correlated with higher rates of positive swabs for common germs (n = 104, 94%), often leading to co-infections (n = 30, 29%). Conversely, Döderlein's cytolysis (n = 56, 4.3% of positive FBE) indicated a predominance of positive human papillomavirus (HPV) swabs (n = 33, 59%). The presence of fungal elements (n = 208, 16% of positive FBE) suggested a higher prevalence of co-infections (n = 62, 30%). Similarly, mixed bacterial flora (n = 470, 36% of positive FBE) and Trichomonas vaginalis (n = 11, 0.8% of positive FBE) correlated with positive swabs for other pathogens, except for Mycoplasma (n = 0). Bacterial vaginosis (n = 443, 34% of positive FBE) was linked to co-infections (n = 142, 32%) and HPV (n = 123, 28%).

CONCLUSION

The importance of conducting FBE in patients with vulvovaginal symptoms is emphasized. This approach aids in determining the need for further diagnostic tests like vaginal swabs, guided by microscopic findings. A strong correlation emerges between the presence of specific alterations in the FBE and an increased prevalence of certain infections.

An insight into the vaginal microbiome of infertile women in Bangladesh using metagenomic approach

Introduction

The dysbiosis of vaginal microbiota is recognized as a potential underlying factor contributing to infertility in women. This study aimed to compare the vaginal microbiomes of infertile and fertile women to investigate their relationship with infertility.

Methods

Metagenomic analysis was conducted on samples from 5 infertile and 5 fertile individuals using both amplicon 16S and metagenomics shotgun sequencing methods.

Results and discussion

In the infertile group, the bacterial community was primarily represented by three major bacterial genera: Lactobacillus (79.42%), Gardnerella (12.56%) and Prevotella (3.33%), whereas, the fertile group exhibited a more diverse composition with over 8 major bacterial genera, accompanied by significantly reduced abundance of Lactobacillus (48.79%) and Gardnerella (6.98%). At the species level, higher abundances of L. iners, L. gasseri and G. vaginalis were observed in the infertile group. Regarding the microbiome composition, only one fertile and two infertile subjects exhibited the healthiest Community State Types, CST-1, while CST-3 was observed among two infertile and one fertile subject, and CST-4 in three other fertile and one infertile subject. Overall, alpha diversity metrics indicated greater diversity and lower species richness in the control (fertile) group, while the infertile group displayed the opposite trend. However, beta-diversity analysis did not show distinct clustering of samples associated with any specific group; instead, it demonstrated CST-type specific clustering. Shotgun metagenomics further confirmed the dominance of Firmicutes, with a greater abundance of Lactobacillus species in the infertile group. Specifically, L. iners and G. vaginalis were identified as the most dominant and highly abundant in the infertile group. Fungi were only identified in the control group, dominated by Penicillium citrinum (62.5%). Metagenome-assembled genomes (MAGs) corroborated read-based taxonomic profiling, with the taxon L. johnsonii identified exclusively in disease samples. MAG identities shared by both groups include Shamonda orthobunyavirus, L. crispatus, Human endogenous retrovirus K113, L. iners, and G. vaginalis. Interestingly, the healthy microbiomes sequenced in this study contained two clusters, Penicillium and Staphylococcus haemolyticus, not found in the public dataset. In conclusion, this study suggests that lower species diversity with a higher abundance of L. iners, L. gasseri and G. vaginalis, may contribute to female infertility in our study datasets. However, larger sample sizes are necessary to further evaluate such association.

Comparative analysis of endometrial, vaginal, and gut microbiota in patients with and without adenomyosis

INTRODUCTION

Alterations in microbiota composition have been implicated in a variety of human diseases. Patients with adenomyosis present immune dysregulation leading to a persistent chronic inflammatory response. In this context, the hypothesis that alterations in the microbiota may be involved in the pathogenesis of adenomyosis, by affecting the epigenetic, immunologic, and biochemical functions of the host, has recently been postulated. The aim of the present study was to compare the microbiota composition in the vagina, endometrium, and gut of individuals with and without adenomyosis.

MATERIAL AND METHODS

Cross-sectional study including 38 adenomyosis patients and 46 controls, performed between September 2021 and October 2022 in a university hospital-based research center. The diagnosis of adenomyosis was based on sonographic criteria. Fecal, vaginal, and endometrial samples were collected. Study of the microbiota using 16S rRNA gene sequencing.

RESULTS

Patients with adenomyosis exhibited a significant reduction in the gut microbial alpha diversity compared with healthy controls (Chao1 p = 0.012, Fisher p = 0.005, Observed species p = 0.005). Beta-diversity analysis showed significant differences in the compositions of both gut and vaginal microbiota between adenomyosis patients and the control group (Adonis p-value = 0.001; R2 = 0.03 and Adonis p-value = 0.034; R2 = 0.04 respectively). Specific bacterial taxa were found to be either overrepresented (Rhodospirillales, Ruminococcus gauvreauii group, Ruminococcaceae, and Actinomyces) or underrepresented in the gut and endometrial microbiota of adenomyosis patients compared with controls. Distinct microbiota profiles were identified among patients with internal and external adenomyosis phenotypes.

CONCLUSIONS

The study revealed reduced gut microbiota diversity in adenomyosis patients, accompanied by distinct compositions in gut and vaginal microbiota compared with controls. Overrepresented or underrepresented bacterial taxa were noted in the gut and endometrial microbiota of adenomyosis patients, with variations in microbiota profiles among those with internal and external adenomyosis phenotypes. These findings suggest a potential association between microbiota and adenomyosis, indicating the need for further research to comprehensively understand the implications of these differences.

Developmental validation of an mRNA kit: A 5-dye multiplex assay designed for body-fluid identification

Identifying the sources of biosamples found at crime scenes is crucial for forensic investigations. Among the markers used for body fluid identification (BFI), mRNA has emerged as a well-studied marker because of its high specificity and remarkable stability. Despite this potential, commercially available mRNA kits specifically designed for BFI are lacking. Therefore, we developed an mRNA kit that includes 21 specific mRNA markers of body fluids, along with three housekeeping genes for BFI, to identify four forensic-relevant fluids (blood, semen, saliva, and vaginal fluids). In this study, we tested 451 single-body-fluid samples, validated the universality of the mRNA kit, and obtained a gene expression profile. We performed the validation studies in triplicates and determined the sensitivity, specificity, stability, precision, and repeatability of the mRNA kit. The sensitivity of the kit was found to be 0.1 ng. Our validation process involved the examination of 59 RNA mixtures, 60 body fluids mixtures, and 20 casework samples, which further established the reliability of the kit. Furthermore, we constructed five classifiers that can handle single-body fluids and mixtures using this kit. The classifiers output possibility values and identify the specific body fluids of interest. Our results showed the reliability and suitability of the BFI kit, and the Random Forest classifier performed the best, with 94% precision. In conclusion, we developed an mRNA kit for BFI which can be a promising tool for forensic practice.

Evidence of Lactobacillus strains shared between the female urinary and vaginal microbiota

Lactobacillus species are common inhabitants of the 'healthy' female urinary and vaginal communities, often associated with a lack of symptoms in both anatomical sites. Given identification by prior studies of similar bacterial species in both communities, it has been hypothesized that the two microbiotas are in fact connected. Here, we carried out whole-genome sequencing of 49 Lactobacillus strains, including 16 paired urogenital samples from the same participant. These strains represent five different Lactobacillus species: L. crispatus, L. gasseri, L. iners, L. jensenii, and L. paragasseri. Average nucleotide identity (ANI), alignment, single-nucleotide polymorphism (SNP), and CRISPR comparisons between strains from the same participant were performed. We conducted simulations of genome assemblies and ANI comparisons and present a statistical method to distinguish between unrelated, related, and identical strains. We found that 50 % of the paired samples have identical strains, evidence that the urinary and vaginal communities are connected. Additionally, we found evidence of strains sharing a common ancestor. These results establish that microbial sharing between the urinary tract and vagina is not limited to uropathogens. Knowledge that these two anatomical sites can share lactobacilli in females can inform future clinical approaches.

Molecular characterization of vaginal microbiota using a new 22-species qRT-PCR test to achieve a relative-abundance and species-based diagnosis of bacterial vaginosis

Background

Numerous bacteria are involved in the etiology of bacterial vaginosis (BV). Yet, current tests only focus on a select few. We therefore designed a new test targeting 22 BV-relevant species.

Methods

Using 946 stored vaginal samples, a new qPCR test that quantitatively identifies 22 bacterial species was designed. The distribution and relative abundance of each species, α- and β-diversities, correlation, and species co-existence were determined per sample. A diagnostic index was modeled from the data, trained, and tested to classify samples into BV-positive, BV-negative, or transitional BV.

Results

The qPCR test identified all 22 targeted species with 95 - 100% sensitivity and specificity within 8 hours (from sample reception). Across most samples, Lactobacillus iners, Lactobacillus crispatus, Lactobacillus jensenii, Gardnerella vaginalis, Fannyhessea (Atopobium) vaginae, Prevotella bivia, and Megasphaera sp. type 1 were relatively abundant. BVAB-1 was more abundant and distributed than BVAB-2 and BVAB-3. No Mycoplasma genitalium was found. The inter-sample similarity was very low, and correlations existed between key species, which were used to model, train, and test a diagnostic index: MDL-BV index. The MDL-BV index, using both species and relative abundance markers, classified samples into three vaginal microbiome states. Testing this index on our samples, 491 were BV-positive, 318 were BV-negative, and 137 were transitional BV. Although important differences in BV status were observed between different age groups, races, and pregnancy status, they were statistically insignificant.

Conclusion

Using a diverse and large number of vaginal samples from different races and age groups, including pregnant women, the new qRT-PCR test and MDL-BV index efficiently diagnosed BV within 8 hours (from sample reception), using 22 BV-associated species.

The Conservation Implications of the Gut Microbiome for Protecting the Critically Endangered Gray Snub-Nosed Monkey (Rhinopithecus brelichi)

The gut microbiota plays a crucial role in regulating energy metabolism, facilitating nutrient absorption, and supporting immune function, thereby assisting the host in adapting to seasonal dietary changes. Here, we compare the gut microbiome composition of wild gray snub-nosed monkeys during winter (from October to December) and spring (from January to March) to understand differences in seasonal nutrient intake patterns. Snub-nosed monkeys are foregut fermenters and consume difficult-to-digest carbohydrates and lichen. To examine the digestive adaptations of gray snub-nosed monkeys, we collected 14 fresh fecal samples for DNA analysis during the winter and spring. Based on 16S rRNA sequencing, metagenomic sequencing, and functional metagenomic analyses, we identified that Firmicutes, Actinobacteria, Verrucomicrobia, and Bacteroidetes constitute a keystone bacterial group in the gut microbiota during winter and spring and are responsible for degrading cellulose. Moreover, the transition in dietary composition from winter to spring was accompanied by changes in gut microbiota composition, demonstrating adaptive responses to varying food sources and availability. In winter, the bacterial species of the genera Streptococcus were found in higher abundance. At the functional level, these bacteria are involved in fructose and mannose metabolism and galactose metabolism c-related pathways, which facilitate the breakdown of glycogen, starch, and fiber found in fruits, seeds, and mature leaves. During spring, there was an increased abundance of bacteria species from the Prevotella and Lactobacillus genera, which aid the digestion of protein-rich buds. Combined, these findings reveal how the gut microbiota adjusts to fluctuations in energy balance and nutrient intake across different seasons in this critically endangered species. Moreover, we also identified Pseudomonas in two samples; the presence of potential pathogens within the gut could pose a risk to other troop members. Our findings highlight the necessity of a conservation plan that focuses on protecting vegetation and implementing measures to prevent disease transmission for this critically endangered species.

Bacteria/Nanozyme Composites: New Therapeutics for Disease Treatment

Bacterial therapy is recognized as a cost-effective treatment for several diseases. However, its development is hindered by limited functionality, weak inherent therapeutic effects, and vulnerability to harsh microenvironmental conditions, leading to suboptimal treatment activity. Enhancing bacterial activity and therapeutic outcomes emerges as a pivotal challenge. Nanozymes have garnered significant attention due to their enzyme-mimic activities and high stability. They enable bacteria to mimic the functions of gene-edited bacteria expressing the same functional enzymes, thereby improving bacterial activity and therapeutic efficacy. This review delineates the therapeutic mechanisms of bacteria and nanozymes, followed by a summary of strategies for preparing bacteria/nanozyme composites. Additionally, the synergistic effects of such composites in biomedical applications such as gastrointestinal diseases and tumors are highlighted. Finally, the challenges of bacteria/nanozyme composites are discussed and propose potential solutions. This study aims to provide valuable insights to offer theoretical guidance for the advancement of nanomaterial-assisted bacterial therapy.

Strong evidence supports the use of estradiol therapy for the treatment of vaginal inflammation: a two-way Mendelian randomization study

OBJECTIVE

Nowadays, there has been limited Mendelian randomization (MR) research focusing on the causal relationship between estradiol and vaginitis. Therefore, this study conducted a two-way MR study to clarify the causal effect and related influencing factors between them.

METHODS

All genetic datasets were obtained using publicly available summary statistics based on individuals of European ancestry from the IEU GWAS database. MR analysis was performed using MR-Egger, weighted median (WM) and inverse variance weighted (IVW) methods to assess the causal relationship between exposure and outcome and to validate the findings by comprehensively evaluating the effects of pleiotropic effects and outliers.

RESULTS

MR analysis revealed no significant causal relationship between estradiol and vaginitis risk. There was a negative correlation between estradiol and age at menarche (IVW, OR: 0.9996, 95% CI: 0.9992-1.0000, P = 0.0295; WM, OR: 0.9995, 95% CI: 0.9993-0.9998, P = 0.0003), and there was a positive correlation between age at menarche and vaginitis (IVW, OR: 1.5108, 95% CI: 1.1474-2.0930, P = 0.0043; MR-Egger, OR: 2.5575, 95% CI: 1.7664-9.6580, P = 0.0013). Estradiol was negatively correlated with age at menopause (IVW, OR: 0.9872, 95% CI: 0.9786-0.9959, P = 0.0041). However, there was no causal relationship between age at menopause and vaginitis (P > 0.05). In addition, HPV E7 Type 16, HPV E7 Type 18, and Lactobacillus had no direct causal effects on estradiol and vaginitis (P > 0.05). Sensitivity analyses revealed no heterogeneity and horizontal pleiotropy.

CONCLUSION

When estrogen levels drop, it will lead to a later age of menarche, and a later age of menarche may increase the risk of vaginitis, highlighting that the longer the female reproductive tract receives estrogen stimulation, the stronger the defense ability is formed, and the prevalence of vaginitis is reduced. In conclusion, this study indirectly supports an association between reduced level of estrogen or short time of estrogen stimulation and increased risk of vaginitis.

Vaginal microbial profile of cervical cancer patients receiving chemoradiotherapy: the potential involvement of Lactobacillus iners in recurrence

The vaginal microbiome is an immune defense against reproductive diseases and can serve as an important biomarker for cervical cancer. However, the intrinsic relationship between the recurrence and the vaginal microbiome in patients with cervical cancer before and after concurrent chemoradiotherapy is poorly understood. Here, we analyzed 125 vaginal microbial profiles from a patient cohort of stage IB-IVB cervical cancer using 16S metagenomic sequencing and deciphered the microbial composition and functional characteristics of the recurrent and non-recurrent both before and after chemoradiotherapy. We demonstrated that the abundance of beneficial bacteria and stability of the microbial community in the vagina decreased in the recurrence group, implying the unique characteristics of the vaginal microbiome for recurrent cervical cancer. Moreover, using machine learning, we identified Lactobacillus iners as the most important biomarker, combined with age and other biomarkers (such as Ndongobacter massiliensis, Corynebacterium pyruviciproducens ATCC BAA-1742, and Prevotella buccalis), and could predict cancer recurrence phenotype before chemoradiotherapy. This study prospectively employed rigorous bioinformatics analysis and highlights the critical role of vaginal microbiota in post-treatment cervical cancer recurrence, identifying promising biomarkers with prognostic significance in the context of concurrent chemoradiotherapy for cervical cancer. The role of L. iners in determining chemoradiation resistance in cervical cancer warrants further detailed investigation. Our results expand our understanding of cervical cancer recurrence and help develop better strategies for prognosis prediction and personalized therapy.

The evolving facets of vaginal microbiota transplantation: reinvigorating the unexplored frontier amid complex challenges

In an age of cutting-edge sequencing methods and worldwide endeavors such as The Human Microbiome Project and MetaHIT, the human microbiome stands as a complex and diverse community of microorganisms. A central theme in current scientific inquiry revolves around reinstating a balanced microbial composition, referred to as "eubiosis," as a targeted approach for treating vast array of diseases. Vaginal Microbiota Transplantation (VMT), inspired by the success of fecal microbiota transplantation, emerges as an innovative therapy addressing vaginal dysbacteriosis by transferring the complete microbiota from a healthy donor. Antibiotics, while effective, pose challenges with adverse effects, high recurrence rates, and potential harm to beneficial Lactobacillus strains. Continued antibiotic usage also sparks worries regarding the development of resistant strains. Probiotics, though showing promise, exhibit inconsistency in treating multifactorial diseases, and concerns linger about their suitability for diverse genetic backgrounds. Given the recurrent challenges associated with antibiotic and probiotic treatments, VMT emerges as an imperative alternative, offering a unique and promising avenue for efficiently and reliably managing vaginal dysbiosis among a majority of women. This review critically evaluates findings from both animal and human studies, offering nuanced insights into the efficacy and challenges of VMT. An extensive analysis of clinical trials, provides a current overview of ongoing and completed trials, shedding light on the evolving clinical landscape and therapeutic potential of VMT. Delving into the origins, mechanisms, and optimized protocols of VMT, the review underscores the imperative for sustained research efforts to advance this groundbreaking gynecological therapy.

Vaginal microbiota and gynecological cancers: a complex and evolving relationship

The vagina hosts a community of microorganisms known as the vaginal microbiota. This community is relatively stable and straightforward, with Lactobacillus species being the most dominant members. The vaginal microbiota has various functions that are essential for maintaining human health and balance. For example, it can metabolise dietary nutrients, produce growth factors, communicate with other bacteria, modulate the immune system, and prevent the invasion of harmful pathogens. When the vaginal microbiota is disrupted, it can lead to diseases and infections. The observed disturbance is distinguished by a reduction in the prevalence of Lactobacillus and a concurrent rise in the number of other bacterial species that exhibit a higher tolerance to low oxygen levels. Gynecologic cancers are a group of cancers that affect the female reproductive organs and tissues, such as the ovaries, uterus, cervix, vagina, vulva, and endometrium. These cancers are a major global health problem for women. Understanding the complex interactions between the host and the vaginal microorganisms may provide new insights into the prevention and treatment of gynecologic cancers. This could improve the quality of life and health outcomes for women.

The vaginal microbial signatures of preterm birth woman

To explore the differences of vaginal microbes in women with preterm birth (PTB), and to construct prediction model. We searched for articles related to vaginal microbiology in preterm women and obtained four 16S rRNA-sequence datasets. We analyzed that for species diversity and differences, and constructed a random forest model with 20 differential genera. We introduce an independent whole genome-sequencing (WGS) data for validation. In addition, we collected vaginal and cervical swabs from 33 pregnant women who delivered spontaneously full-term and preterm infants, performed WGS in our lab to further validate the model. Compared to term birth (TB) samples, PTB women vagina were characterized by a decrease in Firmicutes, Lactobacillus, and an increase in diversity accompanied by the colonization of pathogenic bacteria such as Gardnerella, Atopobium and Prevotella. Twenty genus markers, including Lactobacillus, Prevotella, Streptococcus, and Gardnerella performed well in predicting PTB, with study-to-study transfer validation and LODO validation, different gestation validation showing good results, and in two independent cohorts (external WGS cohorts and woman samples WGS cohorts) in which the accuracy was maintained. PTB women have unique vaginal microbiota characteristics. A predictive model of PTB was constructed and its value validated from multiple perspectives.

Characterization of Vaginal Lactobacilli with Potential Probiotic Properties Isolated from Healthy Women in Northern Iran

Vaginal lactobacilli protect against bacterial vaginosis and vaginal candidiasis. They may have probiotic properties and help maintain the balance and health of the vaginal ecosystem while the loss of these bacteria predisposes females to urinary and genital infections. The aim of this study was to investigate the probiotic potential of vaginal Lactobacillus among healthy females in northern Iran. The Lactobacillus strains were isolated from vaginal samples and were identified by sequencing of the 16S rRNA fragment. Functional properties such as tolerance to low pH, H2O2 production, adherence ability to Hela cells and antagonistic activity against Candida albicans was examined. A total of 38 vaginal lactobacilli strains from five species, including Lactobacillus crispatus (n = 13), Lactobacillus gasseri (n = 10), Lactobacillus acidophilus (n = 6), Lactobacillus jensenii (n = 5) and Lactobacillus johnsonii (n = 4), were identified. All of the species showed significant tolerance to low pH over 24 h (p < 0.001). The best adherence ability to Hela cells was seen in Lactobacillus gasseri strains. Nearly 17 of the strains had higher anti-candida activity compared to the other strains. According to the findings, four lactobacilli strains isolated in the vaginal samples of healthy Iranian women had the best probiotic potential.

Modified Hongteng Baijiang decoction enema improves sequelae of pelvic inflammatory disease by regulating the LIF/JAK2/STAT3 pathway and gut microbiota

OBJECTIVE

The sequelae of pelvic inflammatory disease (SPID) are major causes of secondary infertility. Modified Hongteng Baijiang decoction (MHTBD) has produced positive results in the treatment of patients with chronic pelvic inflammatory disease; however, its role in SPID remains elusive. Therefore, this study clarified the role of MHTBD in SPID pathogenesis.

METHODS

The main components in MHTBD were analyzed by using liquid chromatography‒mass spectrometry (LC/MS). An SPID rat model was established, and the rats were treated with different doses of MHTBD (0.504 g of raw drug/kg, 1.008 g of raw drug/kg, and 2.016 g of raw drug/kg). Endometrial pinopodes were observed via scanning electron microscopy, endometrial thickness and inflammatory cell infiltration were assessed via HE staining, and the expression of estrogen receptor (ER), progesterone receptor (PR), integrin β3 (ITGB3), and CD31 in the endometrium was detected by using immunohistochemistry. Western blot analysis was used to detect the protein expression of LIF, JAK2, p-JAK2, STAT3, and p-STAT3 in the endometrium. Moreover, the changes in the gut microbiota were analyzed via 16S rRNA sequencing.

RESULTS

MHTBD improved endometrial receptivity, attenuated endometrial pathologic damage, reduced inflammatory cell infiltration, decreased ER and PR expression in the endometrium, and promoted the expression of LIF, p-JAK2, and p-STAT3 in the endometrium (p < .05) in SPID rats. Additionally, MHTBD treatment affected the composition of the gut microbiota in SPID rats. Furthermore, MHTBD attenuated endometrial receptivity and pathological damage in SPID rats by promoting the LIF/JAK2/STAT3 pathway.

CONCLUSION

MHTBD attenuates SPID in rats by promoting the LIF/JAK2/STAT3 pathway and improving the composition of the gut microbiota. MHTBD may be a valuable drug for SPID therapy.

Enhancing Therapeutic Efficacy of Cinnamon Essential Oil by Nanoemulsification for Intravaginal Treatment of Candida Vaginitis

Background

Due to its prevalence, recurrence, and the emergence of drug-resistance, Candida vaginitis significantly impacts the well-being of women. Although cinnamon essential oil (CEO) possesses antifungal activity, its hydrophobic properties limit its clinical application.

Purpose

To overcome this challenge, a nanoemulsification technology was employed to prepare cinnamon essential oil-nanoemulsion (CEO@NE), and its therapeutic efficacy and action mechanism for Candida vaginitis was investigated in vivo and in vitro.

Materials and Methods

CEO@NE, composed of 4% CEO, 78% distilled water, and 18% Tween 80, was prepared by ultrasonic nanoemulsification. The physical properties, anti-Candida activity, cytotoxicity, immunomodulatory potential and storage stability of CEO@NE were explored. Subsequently, the effect of intravaginal CEO@NE treatment on Candida vaginitis was investigated in mice. To comprehend the possible mechanism of CEO@NE, an analysis was conducted to ascertain the production of intracellular reactive oxygen species (ROS) in C. albicans.

Results

CEO@NE, with the droplet size less than 100 nm and robust storage stability for up to 8 weeks, exhibited comparable anti-Candida activity with CEO. CEO@NE at the concentration lower than 400 μg/mL had no cytotoxic and immunomodulatory effects on murine splenocytes. Intravaginal treatment of CEO@NE (400 μg/mL, 20 μL/day/mouse for 5 consecutive days) curbed Candida colonization, ameliorated histopathological changes, and suppressed inflammatory cytokine production in mice intravaginally challenged with C. albicans. Notably, this treatment preserved the density of vaginal lactic acid bacteria (LAB) crucial for vaginal health. Co-culturing C. albicans with CEO@NE revealed concentration-dependent augmentation of intracellular ROS generation and ensuing cell death. In addition, co-culturing LPS-stimulated murine splenocytes with CEO@NE yielded a decrease in the generation of cytokines.

Conclusion

This discovery provides insight into the conceivable antifungal and anti-inflammatory mechanisms of CEO@NE to tackle Candida vaginitis. CEO@NE offers a promising avenue to address the limitations of current treatments, providing novel strategy for treating Candida vaginitis.

A non-antibiotic antimicrobial drug, a biological bacteriostatic agent, is useful for treating aerobic vaginitis, bacterial vaginosis, and vulvovaginal candidiasis

Background

Vaginitis is a common infection in women, with approximately 75% of women experiencing at least one episode during their lifetime. Although antimicrobial agents are widely used to treat vaginitis, recurrent vaginitis occurs in some patients. Resistance to these agents is the major cause of recurrent vaginitis. Therefore, there is an urgent need to develop novel drugs.

Methods

We investigated the efficacy of a new biological bacteriostatic agent (BBA), composed of lysozyme, phytoalexin, chitosan oligosaccharide, sinensetin, 18β/20α-glycyrrhizin, and betaine, against vaginitis using in vitro and in vivo studies. First, we evaluated the antibacterial effects of BBA against 13 microbial strains commonly present in aerobic vaginitis, bacterial vaginosis, vulvovaginal candidiasis, and healthy vaginas. Second, we assessed the safety of various doses of BBA administered orally for 4 weeks in female mice. Third, we examined the in vivo anti-proliferative and anti-inflammatory effects of BBA in Candida albicans-, Candida glabrata-, and Gardnerella-induced vaginitis models. Finally, we evaluated the anti-vaginitis effect of a BBA gel prepared with 0.5% (w/v) ammonium acryloyldimethyltaurate/Vp copolymer.

Results

BBA effectively suppressed the growth of the main causative pathogens of vaginitis in vitro. BBA, either undiluted or diluted two-fold, inhibited all microorganisms cultured for 8 h. No obvious organ damage was detected when BBA was administered to mice. Both BBA alone and 70% BBA in a gel formulation effectively inhibited the proliferation of C. albicans, C. glabrata, and Gardnerella in vaginal lavage samples and alleviated tissue inflammation in mice with vaginitis. The 70% BBA gel performed better than BBA alone at treating vaginitis in mice infected with Gardnerella vaginalis.

Conclusion

BBA alone and a 70% BBA gel inhibited the growth of pathogens and effectively alleviated inflammation caused by C. albicans, C. glabrata, and G. vaginalis.

Invasive lactobacillus infection in pediatric patients in a tertiary center in Taiwan - 16 years' experience and literature review

BACKGROUND

Lactobacilli are common microorganisms in the human body. Some species were used as probiotics supplement for many purposes such as preventing necrotizing enterocolitis, or improving allergic diseases or diarrhea. Previously, Lactobacillus infection was thought of as contamination due to its low pathogenicity. However, there have been reports of invasive Lactobacillus infection in immunocompromised patients or patients with comorbidities. The purpose of this study was to analyze the clinical characteristics, antibiotic treatment and outcomes of pediatric patients with invasive Lactobacillus infection.

METHODS

We retrospectively reviewed pediatric patients diagnosed with invasive Lactobacillus infection between 2004 and 2020. Invasive Lactobacillus infection was diagnosed if sterile sites yielded Lactobacillus spp. Clinical manifestations, chronic diseases, potential predisposing factors, medical treatments, antimicrobial susceptibility tests and outcomes were recorded.

RESULTS

Fifteen pediatric patients were diagnosed with invasive Lactobacillus infection, accounting for 2.4% of total invasive Lactobacillus infections during the 16-year period. Eleven infections were bacteremia, two were intra-abdominal infections, and two were biliary tract infections. Fever was the most common symptom. Potential predisposing factors were immunocompromised status, central venous device, prolonged antibiotics use and receiving supplemented probiotics for at least one week. All patients survived with favorable outcomes. Most pathogens were identified as Lactobacillus spp, and two were Lactobacillus rhamnosus, which were related to supplemented probiotics. The antimicrobial susceptibility tests showed that Lactobacilli were all sensitive to ampicillin but resistant to glycopeptides.

CONCLUSION

Invasive Lactobacillus infections in pediatric patients were rare. Despite its low pathogenicity, Lactobacillus could cause invasive infection in those immunocompromised patients.

Role of vaginal microbiota in idiopathic infertility: a prospective study

OBJECTIVE

The causes of idiopathic infertility are still not known; however, it may be associated with microbial etiologies. The present study examines the vaginal microbiota of infertile as well as fertile women longitudinally.

METHODOLOGY

The study was presented and accepted by the Institutional Ethical Committee of Shri Mata Vaishno Devi University, Katra, Jammu and Kashmir (India). An observational, prospective, multicenteric investigation was conducted at the Department of Obstetrics and Gynecology, Government Medical College Jammu, and its affiliated hospitals in Jammu and Kashmir (India). In order to examine the microbial composition, a cohort of 80 female individuals were involved in the screening process. The investigation involved sequencing of the V3-V4 region of 16S rRNA gene, which was subsequently analyzed using the Mothur pipeline.

RESULTS

The study revealed that the vaginal microbiota of infertile women differed from that of healthy women who had previously given birth without any complications. Both populations have variations in their alpha as well as beta diversity and taxonomical composition. The microbial profiles in the cases of infertility are characterized by elevated levels of Gardnerella, Prevotella, Atopobium, and Enterococcus whereas a higher level of Lactobacillus iners was observed in case of fertile women.

CONCLUSION

In conclusion, it can be inferred that the composition of the vaginal microbiome potentially exerts a significant influence on females afflicted with idiopathic infertility.

Microbiota insights into pet ownership and human health

The relationship between pet and owner has already been studied in several studies. Reviewing and summarizing studies on human and pet microbiota and their effects due to keeping pets is the purpose of the current study. Microbiota of the gut, oral cavity, and skin are unique to each individual, and this is also true of their pets (cats and dogs). Microbiota homeostasis is essential for the health of pets and their owners. Dysbiosis or imbalances in the microbiota can increase the risk of disorder progressions such as IBD or Clostridium difficile infections, among others. The microbial communities of humans change as a result of various factors, such as keeping pets. Pet owners frequently contact domestic dogs and cats, which affects their microbiota. As a result of keeping pets, the microbiota of different areas of the human body has changed, which has been associated with a decrease in pathogenic bacteria and an increase in beneficial bacteria.

Lacticaseibacillus rhamnosus TOM 22.8 (DSM 33500) is an effective strategy for managing vaginal dysbiosis, rising the lactobacilli population

AIM

The present study is a single-centre, randomized, controlled clinical trial aimed to evaluate the effectiveness of the probiotic Lacticaseibacillus rhamnosus TOM 22.8 (DSM 33500) strain, orally administrated, to treat vaginal dysbiosis.

METHODS AND RESULTS

Overall, 80 women, with signs and symptoms of vaginal dysbiosis, were enrolled and allocated to the treatment group (A, n=60), who took 1 capsule of the probiotic strain for 10 consecutive days, or the non-treatment group (B, n=20), who did not receive any treatment. Clinical (vaginal signs and symptoms; pH of the vaginal fluid; Amsel criteria; Nugent score; Lactobacillary grade) and microbiological examinations were performed at baseline (T0), 10 days (T1), and 30 (T2) days after the oral administration of the probiotic TOM 22.8 strain. The latter resulted in a restoration of the physiological pH, accompanied by remission or attenuation of clinical signs and symptoms as well as the improvement of the quality of life (QoL). Microbiological data revealed a significant reduction of potentially pathogenic bacteria.

CONCLUSION

The administration of the L. rhamnosus TOM 22.8 probiotic strain could be proposed as an effective strategy for the treatment of vaginal dysbiosis.

Cervical microbiota dysbiosis associated with high-risk Human Papillomavirus infection

High-risk Human Papillomavirus (HR-HPV) genotypes, specifically HPV16 and HPV18, pose a significant risk for the development of cervical intraepithelial neoplasia and cervical cancer. In the multifaceted cervical microenvironment, consisting of immune cells and diverse microbiota, Lactobacillus emerges as a pivotal factor, wielding significant influence in both stabilizing and disrupting the microbiome of the reproductive tract. To analyze the distinction between the cervical microbiota and Lactobacillus-dominant/non-dominant status of HR-HPV and non-infected healthy women, sixty-nine cervical swab samples were analyzed, included 44 with HR-HPV infection and healthy controls. All samples were recruited from Human Papillomavirus-based cervical cancer screening program and subjected to 16s rRNA sequencing analysis. Alpha and beta diversity analyses reveal no significant differences in the cervical microbiota of HR-HPV-infected women, including 16 and 18 HPV genotypes, and those with squamous intraepithelial lesion (SIL), compared to a control group. In this study we identified significantly lower abundance of Lactobacillus mucosae in women with HR-HPV infection compared to the control group. Furthermore, changes in bacterial diversity were noted in Lactobacillus non-dominant (LND) samples compared to Lactobacillus-dominant (LD) in both HR-HPV-infected and control groups. LND samples in HR-HPV-infected women exhibited a cervical dysbiotic state, characterized by Lactobacillus deficiency. In turn, the LD HR-HPV group showed an overrepresentation of Lactobacillus helveticus. In summary, our study highlighted the distinctive roles of L. mucosae and L. helveticus in HR-HPV infections, signaling a need for further research to demonstrate potential clinical implications of cervical microbiota dysbiosis.

Microbiome-derived acidity protects against microbial invasion in Drosophila

Microbial invasions underlie host-microbe interactions resulting in pathogenesis and probiotic colonization. In this study, we explore the effects of the microbiome on microbial invasion in Drosophila melanogaster. We demonstrate that gut microbes Lactiplantibacillus plantarum and Acetobacter tropicalis improve survival and lead to a reduction in microbial burden during infection. Using a microbial interaction assay, we report that L. plantarum inhibits the growth of invasive bacteria, while A. tropicalis reduces this inhibition. We further show that inhibition by L. plantarum is linked to its ability to acidify its environment via lactic acid production by lactate dehydrogenase, while A. tropicalis diminishes the inhibition by quenching acids. We propose that acid from the microbiome is a gatekeeper to microbial invasions, as only microbes capable of tolerating acidic environments can colonize the host. The methods and findings described herein will add to the growing breadth of tools to study microbe-microbe interactions in broad contexts.

Unveiling the gastric microbiota: implications for gastric carcinogenesis, immune responses, and clinical prospects

High-throughput sequencing has ushered in a paradigm shift in gastric microbiota, breaking the stereotype that the stomach is hostile to microorganisms beyond H. pylori. Recent attention directed toward the composition and functionality of this 'community' has shed light on its potential relevance in cancer. The microbial composition in the stomach of health displays host specificity which changes throughout a person's lifespan and is subject to both external and internal factors. Distinctive alterations in gastric microbiome signature are discernible at different stages of gastric precancerous lesions and malignancy. The robust microbes that dominate in gastric malignant tissue are intricately implicated in gastric cancer susceptibility, carcinogenesis, and the modulation of immunosurveillance and immune escape. These revelations offer fresh avenues for utilizing gastric microbiota as predictive biomarkers in clinical settings. Furthermore, inter-individual microbiota variations partially account for differential responses to cancer immunotherapy. In this review, we summarize current literature on the influence of the gastric microbiota on gastric carcinogenesis, anti-tumor immunity and immunotherapy, providing insights into potential clinical applications.

Cervicovaginal microbiota: a promising direction for prevention and treatment in cervical cancer

Cervical cancer is a common malignancy in women, with high incidence rate and mortality. Persistent infection of high-risk human papillomavirus (HPV) is the most important risk factor for cervical cancer and precancerous lesions. Cervicovaginal microbiota (CVM) plays an essential role in the defense of HPV infections and prevention of subsequent lesions. Dominance of Lactobacillus is the key of CVM homeostasis, which can be regulated by host, exogenous and endogenous factors. Dysbiosis of CVM, including altered microbial, metabolic, and immune signatures, can contribute to persist HPV infection, leading to cervical cancer. However, there is no evidence of the causality between CVM and cervical cancer, and the underlying mechanism remains unexplored. Considering the close correlation between CVM dysbiosis and persistent HPV infection, this review will overview CVM, its role in cervical cancer development and related mechanisms, and the prospects for therapeutic applications.

Vaginal and Rectal microbiome changes following administration of a multi-species antenatal probiotic: A randomized control trial

The gut and vaginal microbiome undergo changes during pregnancy which may be protective or harmful to the birthing person. Probiotics have been found to cause protective changes to the gut and vaginal microbiomes, with the potential to improve perinatal outcomes. This randomized control trial compares the vaginal and rectal microbiomes before and after an antenatal probiotic or placebo intervention, with a diverse group of pregnant people and a special focus on racial disparities. The vaginal and rectal microbiomes reveal non-significant increased Lactobacillus in the probiotics group, with a greater increase in participants who identified as Black. Potential implications and future study are discussed.

Medical-Grade Honey as a Potential New Therapy for Bacterial Vaginosis

The prevalence of bacterial vaginosis (BV) among women of reproductive age is 29%. BV arises from a vaginal imbalance marked by reduced levels of lactic acid-producing lactobacilli and an overgrowth of pathogenic anaerobes. The multifactorial nature of BV's pathogenesis complicates its treatment. Current antibiotic therapy exhibits a recurrence rate of about 60% within a year. Recurrence can be caused by antibiotic treatment failure (e.g., due to antimicrobial resistance), the persistence of residual infections (e.g., due to biofilm formation), and re-infection. Because of the high recurrence rates, alternative therapies are required. Medical-grade honey (MGH), known for its antimicrobial and wound healing properties in wound care, emerges as a potential novel therapy for BV. MGH exerts broad-spectrum antimicrobial activity, employing multiple mechanisms to eliminate the risk of resistance. For example, the low pH of MGH and the production of hydrogen peroxide benefit the microbiota and helps restore the natural vaginal balance. This is supported by in vitro studies demonstrating that MGH has an antibacterial effect on several pathogenic bacteria involved in the pathophysiology of BV, while lactobacilli and the vaginal microenvironment can be positively affected. In contrast to antibiotics, MGH exerts anti-biofilm activity, affects the microbiome as pre- and probiotic, and modulates the vaginal microenvironment through its anti-inflammatory, anti-oxidative, physicochemical, and immunomodulatory properties. More clinical research is required to confirm the positive effect of MGH on BV and to investigate the long-term cure rate.

Metagenomic Analysis Reveals A Gut Microbiota Structure and Function Alteration between Healthy and Diarrheic Juvenile Yaks

Diarrhea-induced mortality among juvenile yaks is highly prevalent in the pastoral areas of the Qinghai-Tibet plateau. Although numerous diseases have been linked to the gut microbial community, little is known about how diarrhea affects the gut microbiota in yaks. In this work, we investigated and compared changes in the gut microbiota of juvenile yaks with diarrhea. The results demonstrated a considerable drop in the alpha diversity of the gut microbiota in diarrheic yaks, accompanied by Eysipelatoclostridium, Parabacteroides, and Escherichia-Shigella, which significantly increased during diarrhea. Furthermore, a PICRust analysis verified the elevation of the gut-microbial metabolic pathways in diarrhea groups, including glycine, serine, and threonine metabolism, alanine, aspartate, oxidative phosphorylation, glutamate metabolism, antibiotic biosynthesis, and secondary metabolite biosynthesis. Taken together, our study showed that the harmful bacteria increased, and beneficial bacteria decreased significantly in the gut microbiota of yaks with diarrhea. Moreover, these results also indicated that the dysbiosis of the gut microbiota may be a significant driving factor of diarrhea in yaks.