Lower Relative Abundance Of Lactobacillus Research Articles

Fndc5/irisin deficiency leads to dysbiosis of gut microbiota contributing to the depressive-like behaviors in mice

BackgroundDepression is one of the most common mental diseases and the leading cause of disability worldwide. A dysfunctional gut microbiota-brain axis is one of the main pathological bases of depression. Irisin, an exercise-related myokine, reduces depression-like behaviors and may guide the relief of depressive symptoms by exercise. However, its underlying mechanism remains unclear. MethodsFibronectin type III domain containing 5 (Fndc5)/Irisin was knocked out in male wide-type C57BL/6N mice using CRISPR-cas9. The depression and anxiety symptoms were examined in irisin knockout and control mice with or without chronic unpredictable mild stress by sucrose preference test (SPT), forced swimming test (FST), and tail suspension test (TST). Fecal microbiota was assessed by 16S rRNA sequencing and microbiota-related metabolites using liquid chromatography with tandem mass spectrometry. Differential metabolites were analyzed with the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. ResultsThe knockout mice showed anxiety- and depression-like behaviors and altered diversity and richness of gut microbiota. At the phylum level, these mice had decreased Firmicutes and increased Bacteroidota populations, while at the genus level, they exhibited a low relative abundance of Lactobacillus and Bifidobacterium. Moreover, knocking out of Irisin gene in these mice significantly reduced N-desmethyl-mifepristone (RU 42633) and elevated (-)-stercobilin levels. The KEGG results showed that the microbiota-related metabolites affected by irisin mainly clustered into arginine and proline metabolism and affected the mechanistic target of rapamycin kinase (mTOR) signaling pathway. ConclusionOur findings show that Fndc5/irisin deficiency causes depression in mice by inducing dysbiosis of gut microbiota and changes in microbiota-related metabolites.

Effect of inoculated Daqu on the spontaneous fermentation of Chinese liquor

Inoculated fermentation is widely used to improve the efficiency and quality of food production. However, it is still unclear how the inoculated multi-species starters influence food fermentation. Here we prepared two different types of Daqu, with/without the inoculation of Bacillus licheniformis in spontaneous Daqu fermentation, and studied their effects on liquor fermentation. These two types of Daqu were different in microbial community, and the inoculated Daqu had significantly higher relative abundance of Bacillus (69.2%) and lower relative abundance of Lactobacillus (3.2%) than those of Daqu without inoculation (Bacillus, 13.5%; Lactobacillus, 14.0%). After using with these two types of Daqu, metatranscriptomic analysis revealed that Kazachstania, Naumovozyma, Saccharomyces, Nakaseomyces and Lactobacillus were the transcriptional active genera during liquor fermentation. The transcription of Lactobacillus decreased on days 10 and 20 in liquor fermentation with the inoculated Daqu. The transcription of Kazachstania, Naumovozyma and Saccharomyces decreased on day 10 but increased on day 20 with the inoculated Daqu. Although lactate dehydrogenase decreased in Lactobacillus, alcohol dehydrogenase, aldehyde dehydrogenase and lactate dehydrogenase increased in Saccharomyces on day 20 in fermentation with inoculated Daqu, it indicated an extended succession of Saccharomyces in liquor fermentation. This would facilitate the increase of ethanol, acetic acid and lactic acid contents in liquor fermentation with inoculated Daqu. This work would be beneficial for improving Chinese liquor fermentation.

O-261 The relationship of abnormal vaginal microbiome (dysbiosis of vaginal microbiome) and proinflammatory cytokines in recurrent implantation failure patients

Abstract Study question Is there any correlation between serum cytokine levels and the composition of the vaginal microbiome in recurrent implantation failure (RIF) patients? Summary answer The levels of IFN-γ/IL-10 and TNF-α/IL-6 ratios are higher in patients with dysbiotic microbiome which associates with an imbalance towards inflammation between Th1/Th2 lymphocytes. What is known already In recent years, the development of sequencing-based technologies has enabled the evaluation of the vaginal microbiome. Studies have shown that a vaginal microbiota with less than 90% of Lactobacillus is predictive of IVF treatment outcome and suggests that dysbiosis in the reproductive tract negatively affects the reproductive outcome compared to women with a Lactobacillus-dominated microbiome. Furthermore, it is known that pregnancy is characterized by a Th2-dominant cytokine pattern, and, in contrast, an altered Th1/Th2 ratio, and altered NK cell and macrophage numbers are more prevalent in women with RIF. Study design, size, duration Twenty patients were included in a retrospective study between December 2018 and May 2022. Thirteen had normal microbiome and seven had dysbiotic microbiome. In all of them, a vaginal microbiome sample was analyzed and the levels of cytokines IL-2, IL-4, IL- 6, IL-8, IL-10, VEGF, IFNγ, TNFα, IL-1α, IL-1β, MCP-1 and EGF in serum were measured. Patients with uterine malformations, uterine surgery or other known factors which may influence RIF were excluded from the analysis. Participants/materials, setting, methods To measure the levels of the different cytokines, a sandwich immunoassay with specific antibodies for the cytokines IL-2, IL-4, IL-6, IL-8, IL-10, VEGF, IFNγ, TNFα, IL -1α, IL-1β, MCP-1 and EGF were used. Vaginal microbiome was analyzed by mass sequencing of the V3V4 region of 16S rRNA. The statistical analysis was performed with R Statistical Software, version 4.0.3 and the bioinformatic analysis of vaginal microbiome was performed using QIIME2 and MicrobiomeAnalyst packages. Main results and the role of chance For the ratios between cytokines produced by Th1 lymphocytes and Th2 lymphocytes, we observe that levels of IFN-γ/IL-10 (p = 0,043) and TNF-α/IL-6 (p = 0,021) ratios are higher in patients with dysbiotic microbiome, which have an imbalance towards inflammation. Comparing levels of cytokines with respect to alpha diversity, no differences are observed either individually or in the ratios between Th1/Th2 cytokines. However, the multivariate model that predicts alpha diversity (p = 0.037; AIC=20.734) does consider the IFN-γ/IL-10 and TNF-α/IL-6 aforementioned ratios. Alpha diversity, in turn, is higher in vaginal samples from patients with dysbiotic microbiome (p = 0.003). Regarding beta diversity, it is also higher in patients with altered microbiome (p = 0.007). Considering the relative abundance of each bacteria, we can predict the levels of the aforementioned ratios: for TNF-α/IL-6 ratio, the multivariate model reaches 91.37% of prediction including the relative abundance of Burkholderia, Chryseobacterium, Enterococcus, Escherichia, Gemella, Herbaspirillum, Negativicoccus and Staphylococcus. For IFN-γ/IL-10 ratio, the multivariate model reaches 87,65% of prediction including Aerococcus, Burkholderia, Escherichia, Herbaspirillum, Megasphera, Pseudomonas, Ralstonia and Staphylococcus. It is worth noting the absence of Lactobacillus in these models, which suggests that the relative abundance of some pathogenic bacteria is what alter the production of cytokines, not the lower relative abundance of Lactobacillus. Limitations, reasons for caution The inherent limitations of a retrospective study design and a limited sample size. In addition, cytokine levels were measured in serum and not in vaginal fluid. Additional studies including a metagenomic approach might be able to determine functional groups of bacteria for analysis. Wider implications of the findings These results indicate that pathogenic bacteria, such as Burkholderia and Staphilococcus, which modify cytokine levels and cause inflammation, may also induce an imbalance in the Th1/Th2 ratio. When the vaginal microbiome is altered, the administration of antibiotics or probiotics may improve the immunologic environment, thus, avoiding the use of immunosuppressants. Trial registration number -

Microbiome and metabolome analysis to clarify the interaction between the urine microbiota and serum metabolites in Chinese patients with immunoglobulin A nephropathy

The bacterial and metabolic networks in immunoglobin A nephropathy (IgAN), the most common type of primary chronic glomerulonephritis worldwide, have not been extensively studied. To help develop better methods for the diagnosis, treatment, and prognosis of IgAN, we characterized the alterations of the urinary microbiome and serum metabolome in patients with IgAN. We analyzed serum and urine samples from Chinese patients with IgAN and healthy controls (HCs) using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and 16S ribosomal RNA gene sequencing. Patients with IgAN had a higher relative abundance of Actinomyces and a lower relative abundance of Lactobacillus. The elements of metabolism have been affected, including free amino acids, polyunsaturated fatty acids, and oligopeptides. We also identified the 9 metabolites that might be the core metabolites, including guanidinoacetic acid, apo-[3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming)], and diethanolamine, which linked the metabolic networks between the urinary tract (UT) and blood. Other core metabolites, such as homocitrulline, apo-[3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming)], butyrylcarnitine, formiminoglutamic acid (FIGLU), diethanolamine, and prolylhydroxyproline, were positively correlated with urinary mili-total protein (MTP). Conversely, Lactobacillus was negatively correlated with MTP. We verified the connection between the disruption of the microbiota and serum metabolites, along with the clinical parameters, in patients with IgAN, which may help provide a tool for IgAN interventions.

Mammary tumors alter the fecal bacteriome and permit enteric bacterial translocation

BackgroundCancer patients experience gastrointestinal and behavioral symptoms, and are at increased risk of systemic infection and inflammation. These conditions are a major source of morbidity and decreased quality of life prior to cancer treatment, but poorly defined etiologies impede successful treatment. The gastrointestinal microbiota shape inflammation, influence cancer progression and treatment, and colonize tumors. However, research has not directly determined if peripheral tumors influence the microbiome and intestinal physiology, thus influencing gastrointestinal and behavioral symptoms. Therefore, the purpose of this study was to examine consequences of orthotopic, syngeneic mammary tumor implantation, growth, and resection on fecal bacteriome composition and intestinal barrier function in relation to systemic inflammation and enteric bacterial translocation in mice.MethodsFemale mice were randomized to 3 experimental groups: sham surgical control, tumor recipients, and tumor recipients later receiving tumor-resection. Mice were sacrificed three weeks after tumor implantation or resection for collection of stool, colon, spleen, and brain tissue and analysis.ResultsTumor-bearing mice exhibited several markers of colonic barrier disruption, including dampened expression of tight junction proteins (Cldn1 and Ocln) and elevated circulating lipopolysaccharide binding protein (LBP). Compromised colonic barrier integrity was associated with altered fecal bacterial profiles in tumor-mice, including lower relative abundance of Lactobacillus, but higher Bacteroides. Consistent with colonic barrier disruption and altered microbiomes, tumor-mice displayed markers of systemic inflammation including splenomegaly, higher splenic bacterial load, and elevated splenic and brain pro-inflammatory cytokines. Several bacteria cultured from spleens had 16S rRNA gene amplicons matching those in fecal samples, suggesting they were of intestinal origin. Fecal Lactobacillus was highly-interrelated to physiological parameters disrupted by tumors via correlation network analysis. Tumor resection ameliorated circulating LBP, splenomegaly, and splenic cytokines, but not other parameters associated with loss of colonic barrier integrity and bacterial translocation.ConclusionsOrthotopic mammary tumors alter the microbiome, reduce intestinal barrier function, increase translocation of enteric bacteria, and alter systemic inflammation. This provides insight into how tumors commence gastrointestinal and behavioral symptoms prior to treatment, and identify targets for future therapeutics, such as probiotic Lactobacillus supplementation.

The feature of cervical microbiota associated with the progression of cervical cancer among reproductive females

ObjectivesThe aim of this study was to characterize cervical microbiome feature of reproductive-age women in the progression of squamous intraepithelial lesions (SIL) to cervical cancer. MethodsWe characterized the 16S rDNA cervical mucus microbiome in 94 participants (age from 18 to 52), including 13 cervical cancer (CA), 31 high-grade SIL (HSIL), 10 low-grade SIL (LSIL), 12 HPV-infected (NH) patients and 28 healthy controls (NN). Alpha (within sample) diversity was examined by Shannon and Simpson index, while Beta (between sample) diversity by principle coordinate analysis (PCoA) of weighted Unifrac distances. Relative abundance of microbial taxa was compared using Linear Discriminant Analysis Effect Size (LEfSe). Co-occurrence analysis was performed to identify correlation among marker genera, and Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) to explore functional features and pathways of cervical microbiota. ResultsAlpha diversity(p < 0.05) was higher in severer cervical pathology with lower relative abundance of Lactobacillus as well as higher of anaerobes. Beta diversity (p < 0.01) was significantly different. Marker genera were identified including Porphyromonas, Prevotella and Campylobacter of CA and Sneathia of HSIL. The correlation of differential functional pathways with Prevotella was opposite to that with Lactobacillus. ConclusionOur study suggests differences in cervical microbiota diversity and relative abundance of reproductive-age females in different stages of cervical carcinogenesis. Marker genera might participate in the lesion progression and will be helpful for diagnosis, prevention and treatment. These findings may lead the way to further study of the cervical microbiome in development of cervical cancer.

Shengmai Yin formula modulates the gut microbiota of spleen-deficiency rats

BackgroundSpleen-deficiency syndrome, an important pathological change in traditional Chinese medicine, has been proven to attribute to intestinal dysbacteriosis. Shengmai Yin (SMY), a classic formula for replenishing qi and restoring pulse, is a common medicine for critical emergencies in traditional Chinese Medicine. Interestingly, our previous study established a spleen-deficiency rat model and verified the potency of SMY formula in curing spleen-deficiency rats. Our goal herein was to explore whether SMY can modulate the composition of intestinal flora and alleviate spleen-deficiency in rats.MethodsThis experiment was randomly divided into three groups, namely the normal control group (NC), model control group (MC), and the Shengmai Yin group (SMY). After the treatment, the weight and symptom indexes of the rats were recorded, histological changes in the colon were observed, levels of serum D-xylose, gastrin (GAS), and vasoactive intestinal peptide (VIP) were measured, and gut microbiota profiling was conducted by 16S rRNA sequencing.ResultsThe body mass of the spleen-deficiency model rats significantly decreased compared with that of the NC group, and SMY treatment significantly increased body mass compared with the MC group (P < 0.01). Colon histopathology revealed that SMY treatment alleviated colonic mucosal damage in spleen-deficiency rats. The serum levels of D-xylose and gastrin (GAS) were significant increased by SMY (P < 0.05, P < 0.01), and vasoactive intestinal peptide (VIP) was reduced by SMY (P < 0.01) compared with MC. Furthermore, alpha diversity was significantly decreased in the model rats compared to the normal rats (P < 0.05) and increased with SMY treatment (P < 0.01). The most abundant phyla were Firmicutes and Bacteroidetes, followed by Proteobacteria, Verrucomicrobia, and Actinobacteria. At the genus level, there was a lower relative abundance of Lactobacillus, Bacteroides, Akkermasia, and Allobaculum, and a higher relative abundance of Lachnospiraceae NK4A 136 group, Ruminococcaceae UCG-014, and Sphingomonas in the MC group. The relative abundance of Actinobacteria, Alistipes, Bifidobacterium, Bifidobacterium, Bifidobacteriaceae, Lachnospiraceae NK4A136group, Lactobacillus, Lactobacillaceae, Bacilli, Verrucomicrobiae, and Akkermansia were significantly abundant in the treatment groups, and thus may be singled out as potential biomarkers for SMY in the treatment of spleen deficiency. In addition, analysis on the correlation between species and physicochemical indexes showed that the abundance of Parasutterella was negatively correlated with the change in GAS, and positively correlated with the change in VIP (P < 0.01).ConclusionOur findings have provided preliminary evidence that modulating the gut microbiota may play a role in the treatment of spleen deficiency with SMY. However, further studies are needed to clarify the mechanism by which SMY regulation of related gut microbiota occurs.

A cross-sectional pilot study of birth mode and vaginal microbiota in reproductive-age women.

Recent studies suggest that birth mode (Cesarean section [C-section] or vaginal delivery) is an important event in the initial colonization of the human microbiome and may be associated with long-term health outcomes. We sought to determine the association between a woman's birth mode and her vaginal microbiota in adulthood. We re-contacted 144 adult women from two U.S. studies and administered a brief survey. Vaginal microbiota was characterized on a single sample by amplicon sequencing of the V3-V4 hypervariable regions of the 16S rRNA gene and clustered into community state types (CSTs). We evaluated the association between birth mode and a CST with low relative abundance of Lactobacillus spp. ("molecular bacterial vaginosis" [Molecular-BV]) compared to Lactobacillus-dominated CSTs in logistic regression modeling which adjusted for body mass index, a confounder in this analysis. Twenty-seven women (19%) reported C-section. Overall, C-section showed a non-significant trend towards increased odds of Molecular-BV (aOR = 1.22, 95% CI: 0.45, 3.32), and Prevotella bivia was the strongest single taxa associated with C-section. However, because the two archived studies had different inclusion criteria (interaction p = 0.048), we stratified the analysis by study site. In the study with a larger sample size (n = 88), women born by C-section had 3-fold higher odds of Molecular-BV compared to vaginally-delivered women (aOR = 3.55, p = 0.06, 95% CI: 0.97-13.02). No association was found in the smaller study (n = 56, aOR = 0.19, p = 0.14, 95% CI: 0.02-1.71). This pilot cross-sectional study suggests a possible association between C-section and Molecular-BV in adulthood. However, the analysis is limited by small sample size and lack of comparability in participant age and other characteristics between the study sites. Future longitudinal studies could recruit larger samples of women, address the temporal dynamics of vaginal microbiota, and explore other confounders, including maternal factors, breastfeeding history, and socioeconomic status, which may affect the relationship between birth mode and vaginal microbiota.

Differences in gut microbiota composition of laying hen lines divergently selected on feather pecking

ABSTRACTFeather pecking (FP), a damaging behavior where laying hens peck and pull at feathers of conspecifics, is multifactorial and has been linked to numerous behavioral and physiological characteristics. The gut microbiota has been shown to influence host behavior and physiology in many species, and could therefore affect the development of damaging behaviors, such as FP. Yet, it is unknown whether FP genotypes (high FP [HFP] and low FP [LFP] lines) or FP phenotypes (i.e., individuals differing in FP, feather peckers and neutrals) differ in their gut microbiota composition. Therefore, we identified mucosa-associated microbiota composition of the ileum and cecum at 10 and 30 wk of age. At 30 wk of age, we further identified luminal microbiota composition from combined content of the ileum, ceca, and colon. FP phenotypes could not be distinguished from each other in mucosa-associated or luminal microbiota composition. However, HFP neutrals were characterized by a higher relative abundance of genera of Clostridiales, but lower relative abundance of Lactobacillus for the luminal microbiota composition compared to LFP phenotypes. Furthermore, HFP neutrals had a higher diversity and evenness for the luminal microbiota compared to LFP phenotypes. FP genotypes could not be distinguished from each other in mucosa-associated microbiota composition. Yet, FP genotypes could be distinguished from each other in luminal microbiota composition. HFP birds were characterized by a higher relative abundance of genera of Clostridiales, but lower relative abundance of Staphylococcus and Lactobacillus compared to LFP birds. Furthermore, HFP birds had a higher diversity and evenness for both cecal mucosa-associated and luminal microbiota compared to LFP birds at adult age. In conclusion, we here show that divergent selection on FP can (in)directly affect luminal microbiota composition. Whether differences in microbiota composition are causal to FP or a consequence of FP remains to be elucidated.

The use of inulin and wheat bran only during the starter period or during the entire rearing life of broilers: effects on growth performance, small intestinal maturation, and cecal microbial colonization until slaughter age.

Inulin and wheat bran were added to broiler diets during the starter period or during the entire rearing period to investigate whether the effects of using these ingredients remained until slaughter age. Diets containing no inulin and no wheat bran (CON), 2% inulin (IN), 10% wheat bran (WB), or 2% inulin + 10% wheat bran (IN+WB) were provided until day 11. Thereafter, each dietary treatment was further divided into a continued diet with supplementation or a control diet, resulting in 7 groups (CON, IN/IN, IN/CON, WB/WB, WB/CON, IN+WB/IN+WB, or IN+WB/CON). On day 40, 12 chickens per group were euthanized. The IN/IN group increased the cecal molar ratio of butyrate but had a lower relative abundance of Lactobacillus (P < 0.05). Additionally, the cecal molar ratio of propionate was higher in the IN/CON group compared to the IN/IN group (P = 0.034). The WB/CON group had the best results on BW and feed conversion ratio (FCR) (P < 0.05). Only the cecal molar ratio of iso-butyrate was higher in the WB/WB group (P = 0.013). Moreover, compared to the CON group, both WB/WB and WB/CON groups reduced the relative abundances of Bifidobacterium and Escherichia coli, and only the WB/WB group reduced the relative abundance of Enterobacteriaceae (P < 0.05). Both IN+WB/IN+WB and IN+WB/CON groups increased BW until day 21 and lowered the relative abundance of Bifidobacterium (P < 0.05). The IN+WB/IN+WB group increased the cecal molar ratio of butyrate but reduced the molar ratio of propionate with a higher relative abundance of Enterobacteriaceae (P < 0.05). In conclusion, the lack of positive effects induced by inulin might be explained by the dose being too high. The beneficial effects on BW, FCR, and microbiota induced by wheat bran during the starter period were lasting when supplementation was stopped, suggesting that wheat bran could be a favorable ingredient during the starter period.

Effect of Fortified Daqu on the Microbial Community and Flavor in Chinese Strong-Flavor Liquor Brewing Process.

Daqu, an important fermentation starter for the production of Chinese liquor, as used in the current study included traditional Daqu and fortified Daqu inoculated with Bacillus velezensis and Bacillus subtilis. To evaluate the effect of fortified Daqu on strong-flavor liquor production, the differences of microbial communities among three inoculation patterns of fermented grains (FG) were analyzed by the Illumina MiSeq platform. A higher relative abundance of dominant genera including Bacillus, Lactococcus, Aspergillus, and Candida, and lower relative abundance of Lactobacillus, were observed in FG50, in which mixed Daqu (traditional: fortified Daqu = 1: 1, w/w, 50% fortified Daqu) was used as the starter. Then, volatile compounds of their distillations were also examined by HS-SPME-GC-MS. The results showed that the contents of skeleton flavor components, mainly including important esters and aromatic compounds, were higher in the corresponding liquor L50, which distillated from FG50. Moreover, most esters mainly positively correlated with Lactobacillus and Candida in the bottom layer of FG fermented with 50% fortified Daqu (FG50-B). Aromatic compounds were strongly positively correlated with Bacillus and Aspergillus in the middle layer of FG with 50% fortified Daqu used (FG50-M). In particular, hexyl hexanoate showed a positive correlation with higher abundances of Ruminococcus in the FG with addition of 100% fortified Daqu (FG100). This study observed microbial compositions in the FG with fortified Daqu addition, and it further revealed the correlations between pivotal microbes and main flavor compounds. These results may help to develop effective strategies to regulate microbes for the brewing process and further improve the flavors of Chinese liquor.

Comparison of the gut microbiota of obese individuals from different geographic origins.

Few studies have examined the interaction of human geography, microbial community structure and obesity. We tested obese adult volunteers from France, Saudi Arabia, French Polynesia and from a traditional population in the village of Trois-Sauts in French Guiana by sequencing the V3-V4 region. We also sequenced homemade fermented cachiri beers that were obtained from the traditional Amazonian population and are highly consumed by this population. We found that French and Saudis had significantly less richness and biodiversity in their gut microbiota than Amazonians and Polynesians (p <0.05). Principle coordinate analysis of the overall composition of the genera communities revealed that the microbiomes of Amazonians clustered independently from the other obese individuals. Moreover, we found that Amazonians presented significantly stricter anaerobic genera than the Saudis, French and Polynesians (p < 0.001). Polynesians presented significantly lower relative abundance of Lactobacillus sp. than French (p 0.01) and Saudis (p 0.05). Treponema berlinense and Treponema succinifaciens were only present in the gut microbiome of Amazonians. The cachiri beers presented significantly more bacterial species in common with the gut microbiome of Amazonians (p < 0.005). Obese individuals with different origins present modifications in their gut microbiota, and we provide evidence that the cachiri beers influenced the gut microbiome of Amazonians.

Association between the vaginal microbiota, menopause status, and signs of vulvovaginal atrophy.

The vaginal microbiota helps protect the female genital tract from disease. We sought to describe the composition of the vaginal microbiota in premenopausal, perimenopausal, and postmenopausal women and to explore the association between the microbiota and vulvovaginal atrophy (VVA). Eighty-seven women (aged 35-60 y) were classified as premenopausal (n = 30), perimenopausal (n = 29), or postmenopausal (n = 28) according to Stages of Reproductive Aging Workshop guidelines. Midvaginal bacterial community composition was characterized by 16S ribosomal RNA gene analysis. Bacterial communities clustered into six community state types (CSTs), of which four were dominated by Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners, or Lactobacillus jensenii, and two (CST IV-A and CST IV-B) had low relative abundance of Lactobacillus. CST IV-A was characterized by Streptococcus and Prevotella, whereas CST IV-B was characterized by Atopobium. There were significant associations between menopause stage and CST (P = 0.004) and between VVA and CST (P = 0.002). Perimenopausal women were more likely to be classified as CST IV-A or L. gasseri CST, whereas postmenopausal women were often classified as CST IV-A. CSTs dominated by L. crispatus and L. iners were more prevalent in premenopausal women. Nineteen participants had signs of mild or moderate VVA. Compared with women with no VVA, the vaginal microbiota of women with mild or moderate atrophy had 25-fold greater odds of being classified as CST IV-A versus L. crispatus CST (adjusted odds ratio, 25.89; 95% credible interval, 2.98-406.79). A distinct bacterial community state (CST IV-A) with a low relative abundance of Lactobacillus is associated with VVA. Future studies recruiting a larger number of women are needed to replicate the findings. This study provides an impetus for future longitudinal studies designed to manage, modulate, and restore vaginal microbiota homeostasis, which would provide stronger evidence for a causal relationship with VVA and ultimately improve the treatment and prevention of atrophic vaginitis in menopause.

O13.5 Association between dietary intake and dysbiotic vaginal microbiota

Background Suboptimal nutrition has been associated with an increased risk of bacterial vaginosis (BV). In this study, we examined the association between dietary intake and BV-associated vaginal microbiota. Methods We analysed the baseline visit of the Hormonal Contraception Longitudinal Study, a cohort of reproductive-aged women who reported at enrollment intentions to initiate or cease hormonal contraception (HC). Dietary intake was estimated using the Block Brief 2000 Food Frequency Questionnaire. Vaginal microbiota composition was assessed using 16S rRNA gene analysis and categorised based on the types and relative abundance of bacteria (termed community state types (CSTs)). Nutrients were categorised into quartiles and the associations between nutrients and CST-IV, a low- Lactobacillus CST, were evaluated by logistic regression. Separate models were built for each nutrient controlling for demographics, tobacco use, behavioural factors, HC and dietary variables (total energy intake, and where appropriate, percent of calories from fat, protein, carbohydrates). Results A total of 98 women were included in this analysis. The mean age of the women was 25.9, mean body mass index was 27.9, 29.6% were African American and 47.9% were on HC at enrollment. 26.5% of women had a low relative abundance of Lactobacillus spp. (CST-IV). In adjusted multivariate analyses, the highest quartile of vitamin E (OR: 0.01, 95% CI: 0.001–0.26), zinc (OR: 0.03, 95% CI: 0.18–0.03) and magnesium (OR: 0.06, 95% CI: 0.004–0.75) intake were associated with reduced risk of carrying a low- Lactobacillus CST-IV state. Conclusion Higher intakes of vitamin E, zinc, and magnesium were associated with a decreased risk of having a dysbiotic vaginal microbiota. These findings concur with prior studies that have reported magnesium and zinc deficiencies associated with recurrent bacterial infections and inflammation, and vitamin E (an antioxidant) with anti-inflammatory properties. Dietary interventions targeted at improving intake of select micronutrients may decrease the risk of bacterial vaginosis and its sequelae. Disclosure of interest statement Funding for this study was provided by the National Institutes of Allergy and Infectious Diseases. No pharmaceutical grants were received in the development of this study.

O13.2 Hormonal contraception is associated with stability andlactobacillus-dominance of the vaginal microbiota in a two-year observational study

Introduction Hormonal contraception (HC) has been associated with a reduced risk of bacterial vaginosis (BV). We conducted a prospective study to evaluate the relationship between vaginal microbiota and several HC methods. Methods During 2-years of follow-up, 108 women provided 2,662 mid-vaginal samples. Participants reported three HC methods [oral contraceptive pill (OCP), vaginal ring, implanon]. Controls not taking HC were also followed. Visits were scheduled at baseline, 2 weeks, 4 weeks, 3 months, 6 months, 12 months, 18 months, and 24 months. Additionally, participants self-collected mid-vaginal swabs twice-weekly in the two weeks before each visit. Vaginal microbiota composition was characterised on all samples by 16S rRNA gene analysis of the V3-V4 hypervariable regions. We identified four community state types (CSTs) which were dominated by Lactobacillus species. CST-IV-B was characterised by a low relative abundance of Lactobacillus spp. and higher proportions of BV-associated bacteria (Gardnerella and Atopobium). A multinomial model for dependence of proportions was used to evaluate the association between CST and HC. Jensen-Shannon distances between all pairs of samples were analysed to assess stability of the microbiota longitudinally. Results Women on OCPs had more stable bacterial communities than controls during the 2-year follow-up (p = 0.04). HC (overall) also tended toward greater stability (p = 0.10). The low- Lactobacillus CST-IV-B had an 83% lower probability among OCP users and a 55% lower probability among implanon users. CST-II (L. gasseri-dominated) was significantly higher in all HC types compared to controls. Additionally, OCP users were more likely to be CST-III-A ( L. iners -dominated) and CST-V (L. jensenni-dominated), while CST-III-A was also high among ring users. CST-I (L. crispatus-dominated) was associated with implanon. All reported findings were statistically significant (p Conclusion Women on HC experienced greater stability of the vaginal microbiota over time compared to controls. OCPs and the vaginal ring were protective against transition to a Lactobacillus -depleted state. Disclosure of interest statement The study was funded by the US National Institute of Allergy and Infectious Diseases (NIAID) R01-AI089878. No pharmaceutical grants were received in the development of this study.

Association between the vaginal microbiota, menopause status, and signs of vulvovaginal atrophy

The vaginal microbiota helps protect the female genital tract from disease. We sought to describe the composition of the vaginal microbiota in premenopausal, perimenopausal, and postmenopausal women and to explore the association between the microbiota and vulvovaginal atrophy (VVA). Eighty-seven women (aged 35-60 y) were classified as premenopausal (n = 30), perimenopausal (n = 29), or postmenopausal (n = 28) according to Stages of Reproductive Aging Workshop guidelines. Midvaginal bacterial community composition was characterized by 16S ribosomal RNA gene analysis. Bacterial communities clustered into six community state types (CSTs), of which four were dominated by Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners, or Lactobacillus jensenii, and two (CST IV-A and CST IV-B) had low relative abundance of Lactobacillus. CST IV-A was characterized by Streptococcus and Prevotella, whereas CST IV-B was characterized by Atopobium. There were significant associations between menopause stage and CST (P = 0.004) and between VVA and CST (P = 0.002). Perimenopausal women were more likely to be classified as CST IV-A or L. gasseri CST, whereas postmenopausal women were often classified as CST IV-A. CSTs dominated by L. crispatus and L. iners were more prevalent in premenopausal women. Nineteen participants had signs of mild or moderate VVA. Compared with women with no VVA, the vaginal microbiota of women with mild or moderate atrophy had 25-fold greater odds of being classified as CST IV-A versus L. crispatus CST (adjusted odds ratio, 25.89; 95% credible interval, 2.98-406.79). A distinct bacterial community state (CST IV-A) with a low relative abundance of Lactobacillus is associated with VVA. Future studies recruiting a larger number of women are needed to replicate the findings. This study provides an impetus for future longitudinal studies designed to manage, modulate, and restore vaginal microbiota homeostasis, which would provide stronger evidence for a causal relationship with VVA and ultimately improve the treatment and prevention of atrophic vaginitis in menopause.