16S rDNA Full-Length Assembly Sequencing Technology Analysis of Intestinal Microbiome in Polycystic Ovary Syndrome

Gut Microbiome Composition in Polycystic Ovary Syndrome Adult Women: A Systematic Review and Meta-analysis of Observational Studies

Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder that is frequently linked to anovulation in women who are experiencing infertility. Intestinal flora, also known as the "second genome" of the host, is closely associated with chronic metabolic diseases. Recently, there has been increasing attention on the connection between PCOS and the gut microbiome, and experiments have been conducted. However, the results were unsatisfactory and inconsistent. This review aims to provide a comprehensive overview of the literature investigating the associations between the gut microbiome and PCOS in adults. The goal is to identify whether there are changes in the composition of the gut microbiome in individuals with PCOS. This is the first systematic review to focus on functional alterations in the gut microbiome, which could provide insights into potential mechanisms of microbial involvement in the development of PCOS. We found that there was no significant change in gut microbiome biodiversity in PCOS. Meta-analyses of three studies revealed a significantly higher abundance of Proteobacteria (1.12, 95% CI, 0.21, 2.02, I2 = 0%) in adults with PCOS. At the genus level, Bacteroides, Enterococcus, and Escherichia-Shigella were found to be enriched in patients with PCOS. Species such as Ruminococcus gnavus group, Parabacteroides distasonis, and Bacteroides fragilis showed an increase in PCOS. Metabolic pathways associated with glucose, lipid metabolism, bile acid metabolism, and protein absorption were found to be enriched in individuals with PCOS. The gut microbiome in PCOS is not characterized by lower diversity, but the composition is altered at the phylum, family, genus, or species level. Consequently, the metabolic pathway differs according to the phenotype of PCOS.

Comparative analysis of gut microbiota in children with obstructive sleep apnea: assessing the efficacy of 16S rRNA gene sequencing in metabolic function prediction based on weight status

Background

Analyzing bacterial microbiomes consistently using next-generation sequencing (NGS) is challenging due to the diversity of synthetic platforms for 16S rRNA genes and their analytical pipelines. This study compares the efficacy of full-length (V1-V9 hypervariable regions) and partial-length (V3-V4 hypervariable regions) sequencing of synthetic 16S rRNA genes from human gut microbiomes, with a focus on childhood obesity.

Methods

In this observational and comparative study, we explored the differences between these two sequencing methods in taxonomic categorization and weight status prediction among twelve children with obstructive sleep apnea.

Results

The full-length NGS method by Pacbio® identified 118 genera and 248 species in the V1-V9 regions, all with a 0% unclassified rate. In contrast, the partial-length NGS method by Illumina® detected 142 genera (with a 39% unclassified rate) and 6 species (with a 99% unclassified rate) in the V3-V4 regions. These approaches showed marked differences in gut microbiome composition and functional predictions. The full-length method distinguished between obese and non-obese children using the Firmicutes/Bacteroidetes ratio, a known obesity marker (p = 0.046), whereas the partial-length method was less conclusive (p = 0.075). Additionally, out of 73 metabolic pathways identified through full-length sequencing, 35 (48%) were associated with level 1 metabolism, compared to 28 of 61 pathways (46%) identified through the partial-length method. The full-length NGS also highlighted complex associations between body mass index z-score, three bacterial species (Bacteroides ovatus, Bifidobacterium pseudocatenulatum, and Streptococcus parasanguinis ATCC 15912), and 17 metabolic pathways. Both sequencing techniques revealed relationships between gut microbiota composition and OSA-related parameters, with full-length sequencing offering more comprehensive insights into associated metabolic pathways than the V3-V4 technique.

Conclusion

These findings highlight disparities in NGS-based assessments, emphasizing the value of full-length NGS with amplicon sequence variant analysis for clinical gut microbiome research. They underscore the importance of considering methodological differences in future meta-analyses.

Spatiotemporal patterns of the pregnancy microbiome and links to reproductive disorders

The microbiome of females undergoes extensive remodeling during pregnancy, which is likely to have an impact on the health of both mothers and offspring. Nevertheless, large-scale integrated investigations characterizing microbiome dynamics across key body habitats are lacking. Here, we performed an extensive meta-analysis that compiles and analyzes microbiome profiles from  >10,000 samples across the gut, vagina, and oral cavity of pregnant women from diverse geographical regions. We have unveiled unexpected variations in the taxonomic, functional, and ecological characteristics of microbial communities throughout the course of pregnancy. The gut microbiota showed distinct trajectories between Western and non-Western populations. The vagina microbiota exhibited fluctuating transitions at the genus level across gestation, while the oral microbiota remained relatively stable. We also identified distinctive microbial signatures associated with prevalent pregnancy-related disorders, including opposite variations in the oral and gut microbiota of patients with gestational diabetes and disrupted microbial networks in preterm birth. This study establishes a comprehensive atlas of the pregnancy microbiome by integrating multidimensional datasets and offers foundational insights into the intricate interplay between microbes and host factors that underlie reproductive health.

Microbiome in Female Reproductive Health: Implications for Fertility and Assisted Reproductive Technologies

The microbiome plays a critical role in the process of conception and the outcomes of pregnancy. Disruptions in microbiome homeostasis in women of reproductive age can lead to various pregnancy complications, which significantly impact maternal and fetal health. Recent studies have associated the microbiome in the female reproductive tract (FRT) with assisted reproductive technology (ART) outcomes, and restoring microbiome balance has been shown to improve fertility in infertile couples. This review provides an overview of the role of the microbiome in female reproductive health, including its implications for pregnancy outcomes and ARTs. Additionally, recent advances in the use of microbial biomarkers as indicators of pregnancy disorders are summarized. A comprehensive understanding of the characteristics of the microbiome before and during pregnancy and its impact on reproductive health will greatly promote maternal and fetal health. Such knowledge can also contribute to the development of ARTs and microbiome-based interventions.

Beyond the reproductive tract: gut microbiome and its influence on gynecological health

PURPOSE OF REVIEW

The analysis of microbiome in association with female health is today a "hot topic" with the main focus on microbes in the female reproductive tract. Nevertheless, recent studies are providing novel information of the possible influence of the gut microbiome on gynecological health outcomes, especially as we start to understand that the gut microbiome is an extended endocrine organ influencing female hormonal levels. This review summarizes the current knowledge of the gut microbes in association with gynecological health.

RECENT FINDINGS

The gut microbiome has been associated with endometriosis, polycystic ovary syndrome, gynecological cancers, and infertility, although there is a lack of consistency and consensus among studies due to different study designs and protocols used, and the studies in general are underpowered.

SUMMARY

The interconnection between the gut microbiome and reproductive health is complex and further research is warranted. The current knowledge in the field emphasizes the link between the microbiome and gynecological health outcomes, with high potential for novel diagnostic and treatment tools via modulation of the microenvironment.

Association between gut microbiota and menstrual disorders: a two-sample Mendelian randomization study

Background

Evidence from observational studies and clinical trials suggests that the gut microbiota is associated with gynecological diseases. However, the causal relationship between gut microbiota and menstrual disorders remains to be determined.

Methods

We obtained summary data of gut microbiota from the global consortium MiBio-Gen's genome-wide association study (GWAS) dataset and data on menstrual disorders from the IEU Open GWAS project. MR-Egger, weighted median, inverse variance weighted, simple mode, and weighted mode were used to examine the causal association between gut microbiota and menstrual disorders. Thorough sensitivity studies were performed to confirm the data's horizontal pleiotropy, heterogeneity, and robustness.

Results

Through MR analysis of 119 kinds of gut microbiota and 4 kinds of clinical phenotypes, it was discovered that 23 different kinds of gut microbiota were loosely connected to menstrual disorders. After FDR correction, the results showed that only Escherichia/Shigella (p = 0.00032, PFDR = 0.0382, OR = 1.004, 95%CI = 1.002-1.006) is related to menstrual disorders.

Conclusion

According to our MR Analysis, there are indications of a causal relationship between menstrual disorders and gut microbiota. This finding could lead to new discoveries into the mechanisms behind menstrual disorders and clinical research involving the microbiota.

Effects of Glucagon-Like Peptide-1 Receptor Agonists on Gut Microbiota in Dehydroepiandrosterone-Induced Polycystic Ovary Syndrome Mice: Compared Evaluation of Liraglutide and Semaglutide Intervention

Purpose

Polycystic ovary syndrome (PCOS) is a frequent cause of infertility in reproductive-age women. Our work aims to evaluate the effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on gut microbiota, with metabolic parameters including body weight and the hormone profile in PCOS.

Patients and Methods

Dehydroepiandrosterone (DHEA)-induced PCOS mice were established and then treated with two GLP-1RAs: liraglutide and novel form semaglutide for four weeks. Changes in body weight and metabolic parameters were measured. Fecal samples were collected and analyzed using metagenomic sequencing.

Results

Liraglutide and semaglutide modulated both alpha and beta diversity of the gut microbiota in PCOS. Liraglutide increased the Bacillota-to-Bacteroidota ratio through up-regulating the abundance of butyrate-producing members of Bacillota like Lachnospiraceae. Moreover, liraglutide showed the ability to reverse the altered microbial composition and the disrupted microbiota functions caused by PCOS. Semaglutide increased the abundance of Helicobacter in PCOS mice (p < 0.01) which was the only bacteria found negatively correlated with body weight. Moreover, pathways involving porphyrin and flavonoids were increased after semaglutide intervention.

Conclusion

Liraglutide and semaglutide improved reproductive and metabolic disorders by modulating the whole structure of gut microbiota in PCOS. The greater efficacy in weight loss compared with liraglutide observed after semaglutide intervention was positively related with Helicobacter. The study may provide new ideas in the treatment and the underlying mechanisms of GLP-1RAs to improve PCOS.

Causal relationship between gut microbiota and polycystic ovary syndrome: a literature review and Mendelian randomization study

Introduction

Numerous studies have suggested an association between gut microbiota and polycystic ovarian syndrome (PCOS). However, the causal relationship between these two factors remains unclear.

Methods

A review of observational studies was conducted to compare changes in gut microbiota between PCOS patients and controls. The analysis focused on four levels of classification, namely, phylum, family, genus, and species/genus subgroups. To further investigate the causal relationship, Mendelian randomization (MR) was employed using genome-wide association study (GWAS) data on gut microbiota from the MiBioGen consortium, as well as GWAS data from a large meta-analysis of PCOS. Additionally, a reverse MR was performed, and the results were verified through sensitivity analyses.

Results

The present review included 18 observational studies that met the inclusion and exclusion criteria. The abundance of 64 gut microbiota taxa significantly differed between PCOS patients and controls. Using the MR method, eight bacteria were identified as causally associated with PCOS. The protective effects of the genus Sellimonas on PCOS remained significant after applying Bonferroni correction. No significant heterogeneity or horizontal pleiotropy was found in the instrumental variables (IVs). Reverse MR analyses did not reveal a significant causal effect of PCOS on gut microbiota.

Conclusion

The differences in gut microbiota between PCOS patients and controls vary across observational studies. However, MR analyses identified specific gut microbiota taxa that are causally related to PCOS. Future studies should investigate the gut microbiota that showed significant results in the MR analyses, as well as the underlying mechanisms of this causal relationship and its potential clinical significance.

Alterations in gut and genital microbiota associated with gynecological diseases: a systematic review and meta-analysis

BACKGROUND

Increasing number of studies have demonstrated certain patterns of microbial changes in gynecological diseases; however, the interaction between them remains unclear. To evaluate the consistency or specificity across multiple studies on different gynecological diseases and microbial alterations at different sites of the body (gut and genital tract), we conducted a systematic review and meta-analysis.

METHODS

We searched PubMed, Embase, Web of Science, and Cochrane Library up to December 5, 2022(PROSPERO: CRD42023400205). Eligible studies focused on gynecological diseases in adult women, applied next-generation sequencing on microbiome, and reported outcomes including alpha or beta diversity or relative abundance. The random-effects model on standardized mean difference (SMD) was conducted using the inverse-variance method for alpha diversity indices.

RESULTS

Of 3327 unique articles, 87 eligible studies were included. Significant decreases were found in gut microbiome of patients versus controls (observed species SMD=-0.35; 95%CI, -0.62 to -0.09; Shannon index SMD=-0.23; 95%CI, -0.40 to -0.06), whereas significant increases were observed in vaginal microbiome (Chao1 SMD = 1.15; 95%CI, 0.74 to 1.56; Shannon index SMD = 0.51; 95%CI, 0.16 to 0.86). Most studies of different diagnostic categories showed no significant differences in beta diversity. Disease specificity was observed, but almost all the changes were only replicated in three studies, except for the increased Aerococcus in bacterial vaginosis (BV). Patients with major gynecological diseases shared the enrichment of Prevotella and depletion of Lactobacillus, and an overlap in microbes was implied between BV, cervical intraepithelial neoplasia, and cervical cancer.

CONCLUSIONS

These findings demonstrated an association between alterations in gut and genital microbiota and gynecological diseases. The most observed results were shared alterations across diseases rather than disease-specific alterations. Therefore, further investigation is required to identify specific biomarkers for diagnosis and treatment in the future.

Christensenella minuta, a new candidate next-generation probiotic: current evidence and future trajectories

Background

As the field of probiotic research continues to expand, new beneficial strains are being discovered. The Christensenellaceae family and its newly described member, Christensenella minuta, have been shown to offer great health benefits. We aimed to extensively review the existing literature on these microorganisms to highlight the advantages of their use as probiotics and address some of the most challenging aspects of their commercial production and potential solutions.

Methods

We applied a simple search algorithm using the key words "Christensenellaceae" and "Christensenella minuta" to find all articles reporting the biotherapeutic effects of these microorganisms. Only articles reporting evidence-based results were reviewed.

Results

The review showed that Christensenella minuta has demonstrated numerous beneficial properties and a wider range of uses than previously thought. Moreover, it has been shown to be oxygen-tolerant, which is an immense advantage in the manufacturing and production of Christensenella minuta-based biotherapeutics. The results suggest that Christensenellaceae and Christensenella munita specifically can play a crucial role in maintaining a healthy gut microbiome. Furthermore, Christensenellaceae have been associated with weight management. Preliminary studies suggest that this probiotic strain could have a positive impact on metabolic disorders like diabetes and obesity, as well as inflammatory bowel disease.

Conclusion

Christensenellaceae and Christensenella munita specifically offer immense health benefits and could be used in the management and therapy of a wide range of health conditions. In addition to the impressive biotherapeutic effect, Christensenella munita is oxygen-tolerant, which facilitates commercial production and storage.

Network Pharmacology and Intestinal Microbiota Analysis Revealing the Mechanism of Punicalagin Improving Bacterial Enteritis

BACKGROUND

The Chinese medicine punicalagin (Pun), the most important active ingredient in pomegranate peel, has significant bacteriostatic and anti-inflammatory properties. The potential mechanisms of Pun for bacterial enteritis, however, are unknown.

OBJECTIVE

The goal of our research is to investigate the mechanism of Pun in the treatment of bacterial enteritis using computer-aided drug technology, as well as to investigate the intervention effect of Pun on mice with bacterial enteritis using intestinal flora sequencing.

METHODS

The targets of Pun and Bacterial enteritis were obtained by using the specific database, and cross-targets were screened among these targets, followed by PPI and enrichment analysis of the targets. Furthermore, the degree of binding between Pun and key targets was predicted through molecular docking. After successfully establishing the bacterial enteritis model in vivo, mice were randomly assigned to groups. They were treated for 7 days, the symptoms were observed daily, and the daily DAI and body weight change rate were calculated. Following administration, the intestinal tissue was removed, and the contents were separated. The tight junction protein expression was detected in the small intestine by the immunohistochemical method; ELISA and Western Blot (WB) were performed to detect the expressions of tumor necrosis factor-α (TNF-α) and interleukin- 6 (IL-6) in the serum and intestinal wall of mice. The 16S rRNA sequence was used to determine the composition and diversity of the intestinal flora of mice.

RESULTS

In total, 130 intersection targets of Pun and disease were screened by network pharmacology. The enrichment analysis showed cross genes were closely related and enriched in the cancer regulation and the TNF signal pathway. The active components of Pun could specifically bind to the core targets TNF, IL-6, etc., determined from molecular docking results. In vivo experiment results showed that the symptoms in the PUN group mice were alleviated, and the expression levels of TNF-α and IL-6 were significantly reduced. A Pun can cause substantial changes in the intestinal flora of mice in terms of structure and function.

CONCLUSION

Pun plays a multi-target role in alleviating bacterial enteritis by regulating intestinal flora.

Microbiota Alters and Its Correlation with Molecular Regulation Underlying Depression in PCOS Patients

Depression is one of the complications in patients with polycystic ovary syndrome (PCOS) that leads to considerable mental health. Accumulating evidence suggests that human gut microbiomes are associated with the progression of PCOS and depression. However, whether microbiota influences depression development in PCOS patients is still uncharacterized. In this study, we employed metagenomic sequencing and transcriptome sequencing (RNA-seq) to profile the composition of the fecal microbiota and gene expression of peripheral blood mononuclear cells in depressed women with PCOS (PCOS-DP, n = 27) in comparison to mentally healthy women with PCOS (PCOS, n = 18) and compared with healthy control (HC, n = 27) and patients with major depressive disorder (MDD, n = 29). Gut microbiota assessment revealed distinct patterns in the relative abundance in the PCOS-DP compared to HC, MDD, and PCOS groups. Several gut microbes exhibited uniquely and significantly higher abundance in the PCOS-DP compared to PCOS patients, inducing EC Ruminococcus torques, Coprococcus comes, Megasphaera elsdenii, Acidaminococcus intestini, and Barnesiella viscericola. Bacteroides eggerthii was a potential gut microbial biomarker for the PCOS-DP. RNA-seq profiling identified that 35 and 37 genes were significantly elevated and downregulated in the PCOS-DP, respectively. The enhanced differential expressed genes (DEGs) in the PCOS-DP were enriched in pathways involved in signal transduction and endocrine and metabolic diseases, whereas several lipid metabolism pathways were downregulated. Intriguingly, genes correlated with the gut microbiota were found to be significantly enriched in pathways of neurodegenerative diseases and the immune system, suggesting that changes in the microbiota may have a systemic impact on the expression of neurodegenerative diseases and immune genes. Gut microbe-related DEGs of CREB3L3 and CCDC173 were possible molecular biomarkers and therapeutic targets of women with PCOS-DP. Our multi-omics data indicate shifts in the gut microbiome and host gene regulation in PCOS patients with depression, which is of possible etiological and diagnostic importance.

Berberine interacts with gut microbiota and its potential therapy for polycystic ovary syndrome

Berberine (BBR) is an isoquinoline alkaloid extracted from Chinese medicinal plants showing a tight correlation with gut microbiota. Polycystic ovary syndrome (PCOS) is a prevalent reproductive and endocrine disorder syndrome among women of childbearing age. Dysbiosis, the imbalance of intestinal microorganisms, is a potential factor that takes part in the pathogenesis of PCOS. Recent evidence indicates that berberine offers promise for treating PCOS. Here, we review the recent research on the interaction between berberine and intestinal microorganisms, including the changes in the structure of gut bacteria, the intestinal metabolites after BBR treatment, and the effect of gut microbiota on the bioavailability of BBR. We also discuss the therapeutic effect of BBR on PCOS in terms of gut microbiota and its potential mechanisms.

Alterations of gut microbiota biodiversity and relative abundance in women with PCOS: A systematic review and meta-analysis

BACKGROUND

Numerous studies have implicated that the gut microbiota is associated with polycystic ovary syndrome (PCOS). However, a comprehensive data-based summary shown that the effects of the PCOS on the gut microbiota is minimal. We aim to assess the alterations of gut microbiota in women with PCOS.

METHODS

An electronic search of PubMed, Web of Science, Embase, Cochrane Library and Ovid was conducted for eligible studies published from inception to 28 March 2023, without any language or regional restrictions. We used Newcastle-Ottawa Quality Assessment Scale (NOS) to complete the assessment of the risk of bias and Stata 15.1 software to performed meta-analysis.

RESULTS

There were 19 human observational studies in total with 617 women with PCOS and 439 healthy individuals were identified. Compared to the control group, the Chao index (WMD -28.88, 95% CI -45.78 to -11.98, I2 = 100%), Shannon index (WMD -0.11, 95% CI -0.18 to 0.00, I2 = 92.2%); and observed operational taxonomic units (OTUs) counts (WMD - 23.48, 95% CI -34.44 to -12. 53, I2 = 99.6%) were significantly lower in women with PCOS. The relative abundance of Bacteroidaceae was significantly higher (WMD 0.12, 95% CI 0.02 to 0.22, I2 = 9.2%), however there were no statistical differences in Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, Alcaligenaceae, Bifidobacteriaceae, Clostridiaceae, Enterobacteriaceae, Lachnospiraceae, Prevotellaceae, Ruminococcaceae, Veillonellaceae, Bacteroides, Bifidobacterium, Blautia, Dialister, Escherichia-Shigella, Faecalibacterium, Lachnoclostridium, Lachnospira, Megamonas, Phascolarctobacterium, Prevotella, Roseburia, and Subdoligranulum.

CONCLUSION

We demonstrated the alpha diversity of gut microbiota and the relative abundance of Bacteroidaceae in women with PCOS are altered. The results indicates that dysbiosis may be a potential pathogenetic factor in PCOS and provided reliable information to investigate the role of gut microbiota in the development and progression of PCOS.

The Upper Reproductive System Microbiome: Evidence beyond the Uterus

The microbiome of the female upper reproductive system has garnered increasing recognition and has become an area of interest in the study of women's health. This intricate ecosystem encompasses a diverse consortium of microorganisms (i.e., microbiota) and their genomes (i.e., microbiome) residing in the female upper reproductive system, including the uterus, the fallopian tubes, and ovaries. In recent years, remarkable advancements have been witnessed in sequencing technologies and microbiome research, indicating the potential importance of the microbial composition within these anatomical sites and its impact in women's reproductive health and overall well-being. Understanding the composition, dynamics, and functions of the microbiome of the female upper reproductive system opens up exciting avenues for improving fertility, treating gynecological conditions, and advancing our comprehension of the intricate interplay between the microbiome and the female reproductive system. The aim of this study is to compile currently available information on the microbial composition of the female upper reproductive system in humans, with a focus beyond the uterus, which has received more attention in recent microbiome studies compared with the fallopian tubes and ovaries. In conclusion, this review underscores the potential role of this microbiome in women's physiology, both in health and disease.

Perturbations in gut microbiota composition in patients with polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND

The results of human observational studies on the correlation between gut microbiota perturbations and polycystic ovary syndrome (PCOS) have been contradictory. This study aimed to perform the first systematic review and meta-analysis to evaluate the specificity of the gut microbiota in PCOS patients compared to healthy women.

METHODS

Literature through May 22, 2023, was searched on PubMed, Web of Science, Medline, Embase, Cochrane Library, and Wiley Online Library databases. Unreported data in diversity indices were filled by downloading and processing raw sequencing data. Systematic review inclusion: original studies were eligible if they applied an observational case-control design, performed gut microbiota analysis and reported diversity or abundance measures, sampled general pre-menopausal women with PCOS, and are longitudinal studies with baseline comparison between PCOS patients and healthy females. Systematic review exclusion: studies that conducted interventional or longitudinal comparisons in the absence of a control group. Two researchers made abstract, full-text, and data extraction decisions, independently. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodologic quality. Hedge's g standardized mean difference (SMD), confidence intervals (CIs), and heterogeneity (I2) for alpha diversity were calculated. Qualitative syntheses of beta-diversity and microbe alterations were performed.

RESULTS

Twenty-eight studies (n = 1022 patients, n = 928 control) that investigated gut microbiota by collecting stool samples were included, with 26 and 27 studies having provided alpha-diversity and beta-diversity results respectively. A significant decrease in microbial evenness and phylogenetic diversity was observed in PCOS patients when compared with control participants (Shannon index: SMD = - 0.27; 95% CI, - 0.37 to - 0.16; phylogenetic diversity: SMD = - 0.39; 95% CI, -- 0.74 to - 0.03). We also found that reported beta-diversity was inconsistent between studies. Despite heterogeneity in bacterial relative abundance, we observed depletion of Lachnospira and Prevotella and enrichment of Bacteroides, Parabacteroides, Lactobacillus, Fusobacterium, and Escherichia/Shigella in PCOS. Gut dysbiosis in PCOS, which might be characterized by the reduction of short-chain fatty acid (SCFA)-producing and bile-acid-metabolizing bacteria, suggests a shift in balance to favor pro-inflammatory rather than anti-inflammatory bacteria.

CONCLUSIONS

Gut dysbiosis in PCOS is associated with decreased diversity and alterations in bacteria involved in microbiota-host crosstalk.

TRIAL REGISTRATION

PROSPERO registration: CRD42021285206, May 22, 2023.

The association between gut microbiome and PCOS: evidence from meta-analysis and two-sample mendelian randomization

BACKGROUND

Increasing evidence from observational studies and clinical experimentation has indicated a link between the gut microbiotas (GMs) and polycystic ovary syndrome (PCOS), however, the causality and direction of causality between gut microbiome and PCOS remains to be established.

METHODS

We conducted a comprehensive search of four databases-PubMed, Cochrane Library, Web of Science, and Embase up until June 1, 2023, and subjected the results to a meta-analysis. In this study, a bidirectional two-sample Mendelian randomization (MR) analysis was employed to investigate the impact of gut microbiota on polycystic ovary syndrome (PCOS). The genome-wide association study (GWAS) data for PCOS comprised 113,238 samples, while the GWAS data for gut microbiota were derived from the MiBioGen consortium, encompassing a total sample size of 18,340 individuals. As the largest dataset of its kind, this study represents the most comprehensive genome-wide meta-analysis concerning gut microbiota composition to date. Single nucleotide polymorphisms (SNPs) were selected as instrumental variables at various taxonomic levels, including Phylum, Class, Order, Family, and Genus. The causal associations between exposures and outcomes were assessed using four established MR methods. To correct for multiple testing, the false discovery rate (FDR) method was applied. The reliability and potential biases of the results were evaluated through sensitivity analysis and F-statistics.

RESULTS

The meta-analysis incorporated a total of 20 studies that met the criteria, revealing a close association between PCOS and specific gut microbiota species. As per the results from our MR analysis, we identified six causal associations between the gut microbiome and polycystic ovary syndrome (PCOS). At the genus level, Actinomyces (ORIVW = 1.369, FDR = 0.040), Streptococcus (ORIVW = 1.548, FDR = 0.027), and Ruminococcaceae UCG-005 (ORIVW = 1.488, FDR = 0.028) were identified as risk factors for PCOS. Conversely, Candidatus Soleaferrea (ORIVW = 0.723, FDR = 0.040), Dorea (ORIVW = 0.580, FDR = 0.032), and Ruminococcaceae UCG-011 (ORIVW = 0.732, FDR = 0.030) were found to be protective factors against PCOS. Furthermore, the MR-PRESSO global test and MR-Egger regression indicated that our study results were not affected by horizontal pleiotropy (p > 0.05). Finally, the leave-one-out analysis corroborated the robustness of the MR findings.

CONCLUSION

Both our meta-analysis and MR study indicates that there is a causal relationship between the gut microbiome and PCOS, which may contribute to providing novel insights for the development of new preventive and therapeutic strategies for PCOS.

Microbial composition across body sites in polycystic ovary syndrome: a systematic review and meta-analysis

Polycystic ovary syndrome (PCOS) is an endocrine disorder affecting reproductive-aged women, but the cause remains unclear. Recent evidence has linked microbial composition with PCOS; however, the results are inconsistent. The aim of this systematic review was to gather current knowledge of the microbes across body sites (oral cavity, blood, vagina/cervix, gut) in women with PCOS, and meta-analyse the microbial diversity in PCOS. For this purpose, a systematic search using PubMed, Web of Science, Cochrane and Scopus was carried out. After selection, 34 studies met the inclusion criteria. Most of the studies associated changes in the microbiome with PCOS, whereas heterogeneity of the studies in terms of ethnicity, body mass index (BMI) and methodology, among other confounders, made it difficult to corroborate this relationship. In fact, 19 out of 34 of the studies were categorised as having high risk of bias when the quality assessment was conducted. Our meta-analysis on the gut microbiome of 14 studies demonstrated that women with PCOS possess significantly lower microbial alpha diversity compared with controls (SMD = -0.204; 95% CI -0.360 to -0.048; P = 0.010; I2 = 5.508, by Shannon Index), which may contribute to the development of PCOS. Nevertheless, future studies should specifically overcome the shortcomings of the current studies by through well planned and conducted studies with larger sample sizes, proper negative and positive controls and adequate case-control matching.

Characterization of bacterial communities in ticks parasitizing cattle in a touristic location in southwestern China

The purpose of this study was to investigate tick species around Mount Fanjing and analyze bacterial communities in two species - Rhipicephalus microplus and Haemaphysalis longicornis - parasitizing cattle in Tongren, Guizhou province, Southwest China, using high-throughput sequencing methods. In April 2019, ticks were collected from five sites in Jiangkou County, Yinjiang County, and Songtao County. In total, 296 ticks were collected, comprising two genera and three species: H. longicornis, Haemaphysalis flava, and R. microplus. Rhipicephalus microplus was the most representative species (57.4%) within the collected group, being the dominant species in Tongren City, followed by H. longicornis (39.5%) and H. flava (3.0%). Beta-diversity analysis revealed differences in bacterial community composition among the tick species. The bacterial community structure of R. microplus collected in the three counties was highly similar. Chlorella and Bacillus were highly abundant in H. longicornis. Rickettsia was detected at high relative abundance in R. microplus but in low relative abundance in H. longicornis, suggesting that Rickettsia is more associated with R. microplus than with H. longicornis. More in-depth investigations are needed to determine the pathogenic risk of Rickettsia and its relationship with the host. This is the first survey on tick-borne bacterial communities in this area, which is of great significance for the prevention and control of tick-borne diseases locally.

Impact of a Lactobacillus dominant cervical microbiome, based on 16S-FAST profiling, on the reproductive outcomes of IVF patients

Objective

This study assessed the impact of the cervical microbiome on reproductive outcomes in frozen embryo transfer (FET) patients.

Study design

This cross-sectional study included 120 women (aged 20-40 years) undergoing FET. A cervical sample obtained before embryo transfer was analyzed using 16S full-length assembly sequencing technology (16S-FAST), which detects full length 16S rDNA.

Results

We found that >48% of the identified Lactobacillus species were novel. The cervical microbiome was clustered into three cervical microbiome types (CMT): CMT1, dominated by L. crispatus; CMT2, dominated by L. iners; and CMT3, dominated by other bacteria. CMT1 had a significantly higher biochemical pregnancy rate (P=0.008) and clinical pregnancy rate (P=0.006) than CMT2 and CMT3. Logistic analysis showed that compared to CMT1, CMT2 and CMT3 were independent risk factors for biochemical pregnancy failure (odds ratio [OR]: 6.315, 95% confidence interval [CI]: 2.047-19.476, P=0.001; OR: 3.635, 95% CI: 1.084-12.189, P=0.037) and clinical pregnancy failure (OR: 4.883, 95% CI: 1.847-12.908, P=0.001; OR: 3.478, 95% CI: 1.221-9.911, P=0.020). A L. crispatus-dominated group as a diagnostic indicator of biochemical and clinical pregnancy positive had area under the curve (AUC) values of 0.651(P=0.008) and 0.645(P=0.007), respectively. Combining the cervical microbiome with embryonic stage optimized the diagnostic performance for biochemical and clinical pregnancy failure with AUC values of 0.743(P<0.001) and 0.702(P<0.001), respectively. Additionally, relative abundance of L. crispatus predicted biochemical pregnancy positive with AUC values of 0.679(P=0.002) and clinical pregnancy positive with AUC values of 0.659(P=0.003).

Conclusion

Cervical microbiome profiling using 16S-FAST enables stratification of the chance of becoming pregnant prior to FET. Knowledge of the cervical microbiota may enable couples to make more balanced decisions regarding the timing and continuation of FET treatment cycles.

Effects of Yulin Tong Bu formula on modulating gut microbiota and fecal metabolite interactions in mice with polycystic ovary syndrome

BACKGROUND

Polycystic ovarian syndrome (PCOS) is a common endocrine disorder characterized by hyperandrogenism, ovarian dysfunction and polycystic ovarian morphology. Gut microbiota dysbiosis and metabolite are associated with PCOS clinical parameters. Yulin Tong Bu formula (YLTB), a traditional Chinese medicine formula, has been recently indicated to be capable of ameliorating polycystic ovary symptoms and correcting abnormal glucose metabolism. However, the therapeutic mechanism of YLTB on PCOS has not been fully elucidated.

METHODS

A pseudo sterile mouse model was established during this four-day acclimatization phase by giving the animals an antibiotic cocktail to remove the gut microbiota. Here, the therapeutic effects of YLTB on PCOS were investigated using dehydroepiandrosterone plus high-fat diet-induced PCOS mice model. Female prepuberal mice were randomly divided into three groups; namely, the control group, PCOS group and YLTB (38.68 g·kg^-1·day^-1) group. To test whether this effect is associated with the gut microbiota, we performed 16S rRNA sequencing studies to analyze the fecal microbiota of mice. The relationships among metabolites, gut microbiota, and PCOS phenotypes were further explored by using Spearman correlation analysis. Then, the effect of metabolite ferulic acid was then validated in PCOS mice.

RESULTS

Our results showed that YLTB treatment ameliorated PCOS features (ovarian dysfunction, delayed glucose clearance, decreased insulin sensitivity, deregulation of glucolipid metabolism and hormones, etc.) and significantly attenuated PCOS gut microbiota dysbiosis. Spearman correlation analysis showed that metabolites such as ferulic acid and folic acid are negatively correlated with PCOS clinical parameters. The effect of ferulic acid was similar to that of YLTB. In addition, the bacterial species such as Bacteroides dorei and Bacteroides fragilis were found to be positively related to PCOS clinical parameters, using the association study analysis.

CONCLUSION

These results suggest that YLTB treatment systematically regulates the interaction between the gut microbiota and the associated metabolites to ameliorate PCOS, providing a solid theoretical basis for further validation of YLTB effect on human PCOS trials.

Polycystic Ovary Syndrome and Gut Microbiota: Phenotype Matters

Abnormalities in gut microbiota diversity are considered important mechanisms in metabolic disorders in polycystic ovarian syndrome (PCOS). However, the data on the association of these disorders with the PCOS phenotype remain controversial. The objectives of this study were to estimate the alpha diversity of the gut microbiota of healthy women and PCOS patients depending on phenotype. The study participants (184 premenopausal women: 63 with PCOS, 121 without PCOS) were recruited during the annual employment assessment in the Irkutsk Region and the Buryat Republic (Russia) in 2016-2019. For PCOS diagnosis, we used the Rotterdam (2003) criteria and definitions of PCOS phenotypes. Five indexes of alpha diversity (ASV, Shannon, Simpson, Chao, and ACE) were estimated for the gut microbiota in all participants using amplicon metasequencing. As a result, two out of five alpha diversity indexes showed a statistical difference between the non-PCOS and PCOS groups. We did not find a significant difference in the alpha diversity of gut microbiota in the subgroups of women with hyperandrogenic PCOS phenotypes vs non-androgenic phenotype D and the group of women with the presence of only one of the PCOS criteria. Nevertheless, "classic" PCOS phenotypes demonstrated the most significant decrease in alpha diversity compared with healthy women without any signs of PCOS.

The Gut Microbiome and Female Health

The possession of two X chromosomes may come with the risk of various illnesses, females are more likely to be affected by osteoarthritis, heart disease, and anxiety. Given the reported correlations between gut microbiome dysbiosis and various illnesses, the female gut microbiome is worthy of exploration. Herein, we discuss the composition of the female gut microbiota and its dysbiosis in pathologies affecting the female population. Using PubMed, we performed a literature search, using key terms, namely: "gut microbiome", "estrogen", "menopause", "polycystic ovarian syndrome", "pregnancy", and "menstruation". In polycystic ovarian syndrome (PCOS), the abundance of Bacteroides vulgatus, Firmicutes, Streptococcus, and the ratio of Escherichia/Shigella was found to be increased while that of Tenericutes ML615J-28, Tenericutes 124-7, Akkermansia, Ruminococcaceae, and Bacteroidetes S24-7 was reduced. In breast cancer, the abundance of Clostridiales was enhanced, while in cervical cancer, Prevotella, Porphyromonas, and Dialister were enhanced but Bacteroides, Alistipes, and members of Lachnospiracea, were decreased. In ovarian cancer, Prevotella abundance was increased. Interestingly, the administration of Lactobacillus acidophilus, Bifidobacterium bifidum, Lactobacillus reuteri, and Lactobacillus fermentum ameliorated PCOS symptoms while that of a mix of Bifidobacterium lactis W51, Bifidobacterium bifidum W23, Lactobacillus brevis W63, Bifidobacterium lactis W52, Lactobacillus salivarius W24, Lactobacillus acidophilus W37, Lactococcus lactis W19, Lactobacillus casei W56, and Lactococcus lactis W58 alleviated vascular malfunction and arterial stiffness in obese postmenopausal women, and finally, while further research is needed, Prevotella maybe protective against postmenopausal bone mass loss. As several studies report the therapeutic potential of probiotics and since the gut microbiota of certain female pathological states has been relatively characterized, we speculate that the administration of certain bacterial species as probiotics is warranted, as novel independent or adjunct therapies for various female pathologies.

Multi-omics analyses reveal the specific changes in gut metagenome and serum metabolome of patients with polycystic ovary syndrome

Objective

The purpose of this study was to investigate the specific alterations in gut microbiome and serum metabolome and their interactions in patients with polycystic ovary syndrome (PCOS).

Methods

The stool samples from 32 PCOS patients and 18 healthy controls underwent the intestinal microbiome analysis using shotgun metagenomics sequencing approach. Serum metabolome was analyzed by ultrahigh performance liquid chromatography quadrupole time-of-flight mass spectrometry. An integrative network by combining metagenomics and metabolomics datasets was constructed to explore the possible interactions between gut microbiota and circulating metabolites in PCOS, which was further assessed by fecal microbiota transplantation (FMT) in a rat trial.

Results

Fecal metagenomics identified 64 microbial strains significantly differing between PCOS and healthy subjects, half of which were enriched in patients. These changed species showed an ability to perturb host metabolic homeostasis (including insulin resistance and fatty acid metabolism) and inflammatory levels (such as PI3K/Akt/mTOR signaling pathways) by expressing sterol regulatory element-binding transcription factor-1, serine/threonine-protein kinase mTOR, and 3-oxoacyl-[acyl-cattier-protein] synthase III, possibly suggesting the potential mechanisms of gut microbiota underlying PCOS. By integrating multi-omics datasets, the panel comprising seven strains (Achromobacter xylosoxidans, Pseudomonas sp. M1, Aquitalea pelogenes, Porphyrobacter sp. HL-46, Vibrio fortis, Leisingera sp. ANG-Vp, and Sinorhizobium meliloti) and three metabolites [ganglioside GM3 (d18:0/16:0), ceramide (d16:2/22:0), and 3Z,6Z,9Z-pentacosatriene] showed the highest predictivity of PCOS (AUC: 1.0) with sensitivity of 0.97 and specificity of 1.0. Moreover, the intestinal microbiome modifications by FMT were demonstrated to regulate PCOS phenotypes including metabolic variables and reproductive hormones.

Conclusion

Our findings revealed key microbial and metabolite features and their interactions underlying PCOS by integrating multi-omics approaches, which may provide novel insights into discovering clinical diagnostic biomarkers and developing efficient therapeutic strategies for PCOS.

Polycystic Ovary Syndrome and Endometrial Cancer: A Scoping Review of the Literature on Gut Microbiota

Gut dysbiosis has been associated with polycystic ovary syndrome (PCOS) and endometrial cancer (EC) but no studies have investigated whether gut dysbiosis may explain the increased endometrial cancer risk in polycystic ovary syndrome. The aim of this scoping review is to evaluate the extent and nature of published studies on the gut microbiota in polycystic ovary syndrome and endometrial cancer and attempt to find any similarities between the composition of the microbiota. We searched for publications ranging from the years 2016 to 2022, due to the completion date of the ‘Human Microbiome Project’ in 2016. We obtained 200 articles by inputting keywords such as ‘gut microbiome’, ‘gut microbiota’, ‘gut dysbiosis’, ‘PCOS’, and ‘endometrial cancer’ into search engines such as PubMed and Scopus. Of the 200 identified in our initial search, we included 25 articles in our final review after applying the exclusion and inclusion criteria. Although the literature is growing in this field, we did not identify enough published studies to investigate whether gut dysbiosis may explain the increased EC risk in PCOS. Within the studies identified, we were unable to identify any consistent patterns of the microbiome similarly present in studies on women with PCOS compared with women with EC. Although we found that the phylum Firmicutes was similarly decreased in women with PCOS and studies on women with EC, there was however significant variability within the studies identified making it highly likely that this may have arisen by chance. Further research pertaining to molecular and microbiological mechanisms in relation to the gut microbiome is needed to elucidate a greater understanding of its contribution to the pathophysiology of endometrial cancer in patients with polycystic ovarian syndrome.

16S-FASAS: an integrated pipeline for synthetic full-length 16S rRNA gene sequencing data analysis

Background

The full-length 16S rRNA sequencing can better improve the taxonomic and phylogenetic resolution compared to the partial 16S rRNA gene sequencing. The 16S-FAS-NGS (16S rRNA full-length amplicon sequencing based on a next-generation sequencing platform) technology can generate high-quality, full-length 16S rRNA gene sequences using short-read sequencers, together with assembly procedures. However there is a lack of a data analysis suite that can help process and analyze the synthetic long read data.

Results

Herein, we developed software named 16S-FASAS (16S full-length amplicon sequencing data analysis software) for 16S-FAS-NGS data analysis, which provided high-fidelity species-level microbiome data. 16S-FASAS consists of data quality control, de novo assembly, annotation, and visualization modules. We verified the performance of 16S-FASAS on both mock and fecal samples. In mock communities, we proved that taxonomy assignment by MegaBLAST had fewer misclassifications and tended to find more low abundance species than the USEARCH-UNOISE3-based classifier, resulting in species-level classification of 85.71% (6/7), 85.71% (6/7), 72.72% (8/11), and 70% (7/10) of the target bacteria. When applied to fecal samples, we found that the 16S-FAS-NGS datasets generated contigs grouped into 60 and 56 species, from which 71.62% (43/60) and 76.79% (43/56) were shared with the Pacbio datasets.

Conclusions

16S-FASAS is a valuable tool that helps researchers process and interpret the results of full-length 16S rRNA gene sequencing. Depending on the full-length amplicon sequencing technology, the 16S-FASAS pipeline enables a more accurate report on the bacterial complexity of microbiome samples. 16S-FASAS is freely available for use at https://github.com/capitalbio-bioinfo/FASAS.

The double-edged sword of probiotic supplementation on gut microbiota structure in Helicobacter pylori management

As Helicobacter pylori management has become more challenging and less efficient over the last decade, the interest in innovative interventions is growing by the day. Probiotic co-supplementation to antibiotic therapies is reported in several studies, presenting a moderate reduction in drug-related side effects and a promotion in positive treatment outcomes. However, the significance of gut microbiota involvement in the competence of probiotic co-supplementation is emphasized by a few researchers, indicating the alteration in the host gastrointestinal microbiota following probiotic and drug uptake. Due to the lack of long-term follow-up studies to determine the efficiency of probiotic intervention in H. pylori eradication, and the delicate interaction of the gut microbiota with the host wellness, this review aims to discuss the gut microbiota alteration by probiotic co-supplementation in H. pylori management to predict the comprehensive effectiveness of probiotic oral administration.Abbreviations: acyl-CoA- acyl-coenzyme A; AMP- antimicrobial peptide; AMPK- AMP-activated protein kinase; AP-1- activator protein 1; BA- bile acid; BAR- bile acid receptor; BCAA- branched-chain amino acid; C2- acetate; C3- propionate; C4- butyrate; C5- valeric acid; CagA- Cytotoxin-associated gene A; cAMP- cyclic adenosine monophosphate; CD- Crohn's disease; CDI- C. difficile infection; COX-2- cyclooxygenase-2; DC- dendritic cell; EMT- epithelial-mesenchymal transition; FMO- flavin monooxygenases; FXR- farnesoid X receptor; GPBAR1- G-protein-coupled bile acid receptor 1; GPR4- G protein-coupled receptor 4; H2O2- hydrogen peroxide; HCC- hepatocellular carcinoma; HSC- hepatic stellate cell; IBD- inflammatory bowel disease; IBS- irritable bowel syndrome; IFN-γ- interferon-gamma; IgA immunoglobulin A; IL- interleukin; iNOS- induced nitric oxide synthase; JAK1- janus kinase 1; JAM-A- junctional adhesion molecule A; LAB- lactic acid bacteria; LPS- lipopolysaccharide; MALT- mucosa-associated lymphoid tissue; MAMP- microbe-associated molecular pattern; MCP-1- monocyte chemoattractant protein-1; MDR- multiple drug resistance; mTOR- mammalian target of rapamycin; MUC- mucin; NAFLD- nonalcoholic fatty liver disease; NF-κB- nuclear factor kappa B; NK- natural killer; NLRP3- NLR family pyrin domain containing 3; NOC- N-nitroso compounds; NOD- nucleotide-binding oligomerization domain; PICRUSt- phylogenetic investigation of communities by reconstruction of unobserved states; PRR- pattern recognition receptor; RA- retinoic acid; RNS- reactive nitrogen species; ROS- reactive oxygen species; rRNA- ribosomal RNA; SCFA- short-chain fatty acids; SDR- single drug resistance; SIgA- secretory immunoglobulin A; STAT3- signal transducer and activator of transcription 3; T1D- type 1 diabetes; T2D- type 2 diabetes; Th17- T helper 17; TLR- toll-like receptor; TMAO- trimethylamine N-oxide; TML- trimethyllysine; TNF-α- tumor necrosis factor-alpha; Tr1- type 1 regulatory T cell; Treg- regulatory T cell; UC- ulcerative colitis; VacA- Vacuolating toxin A.

Oral-Gut Microbiome Analysis in Patients With Metabolic-Associated Fatty Liver Disease Having Different Tongue Image Feature

Objective

The objective of this study was to identify the biological correlation between the tongue coating color and oral and gut micro-characteristics in metabolic-associated fatty liver disease (MAFLD) patients.

Method

The characteristics of the tongue coating were examined using an automatic tongue diagnosis system. Tongue coating and stool samples were collected from 38 MAFLD patients, and 16S rDNA full-length assembly sequencing technology (16S-FAST) was used for bioinformatic analysis.

Results

Twenty-two and 16 subjects were included in two distinct clusters according to the white/yellow color of the tongue coating, which was assessed by the L*a*b* values of the image. Upon analyzing the microorganisms in the tongue coating, 66 and 62 pathognomonic bacterial genera were found in the White and Yellow Coating Groups, respectively. The abundance of Stomatobaculumis positively correlated with the a* values of the tongue coating in the White Coating Group, while Fusobacterium, Leptotrichia, and Tannerella abundance was significantly correlated with the b* values in the Yellow Coating Group. Function prediction mainly showed the involvement of protein families related to BRITE hierarchies and metabolism. The MHR (MONO%/high-density lipoprotein cholesterol) of the Yellow Coating Group was higher than that of the White Coating Group.

Conclusion

In MAFLD patients, lower a* values and higher b* values are indicators of a yellow tongue coating. There were also significant differences in the flora of different tongue coatings, with corresponding changes in the intestinal flora, indicating a correlation between carbohydrate metabolism disorders and inflammation in the oral microbiome.

Interplay between PCOS and microbiome: The road less travelled

Polycystic ovarian syndrome (PCOS) is a complicated neuro-endocrinal, reproductive, and metabolic condition. It encompasses patterns such as hyperandrogenism, recurrent cysts triggered by steroidogenic functional aberrations in the ovaries, overweight, chronic inflammation, and more. The underlying cause of this heterogeneous illness is obscure, although it is suspected to be driven by a blend of environmental and hereditary factors. In recent years, the connection between the microbiome and PCOS has been acknowledged and is thought to be involved in the genesis of the syndrome's emergence. Microbiota vary in different pathological features of PCOS, and fundamental pathways linked to their involvement in the commencement of diverse clinical presentations in PCOS open up a new avenue for its management. Prebiotic, probiotic, synbiotic, and fecal-microbiota-transplant, by promoting eubiosis and nullifying the effect caused by the altered microbial profile in PCOS women, can aid in management of diverse phenotypes associated with the syndrome. These microbiota-mediated treatments improve PCOS women's metabolic, inflammatory, and hormonal profiles. However, more studies are needed to elucidate the mechanisms that drive this positive effect.

Gut and Vaginal Microbiomes in PCOS: Implications for Women's Health

PCOS is defined as a kind of endocrine and metabolic disorder which affects females at reproductive ages, is becoming much more common, nowadays. Microbiomes are known as microorganisms that inhabit the body to play a vital role in human health. In recent years, several basic and clinical studies have tried to investigate the correlation between the reproductive health/disorder and microbiomes (gut microbiomes and vaginal microbiomes). However, the mechanism is still unclear. In this review, we reviewed the relationship between PCOS and microbiomes, including gut/vaginal microbiomes compositions in PCOS, mechanism of microbiomes and PCOS, and then collectively focused on the recent findings on the influence of microbiomes on the novel insight regarding the therapeutic strategies for PCOS in the future clinical practice.