Vaginal microbiome and metabolome highlight specific signatures of bacterial vaginosis

Abstract

In this study, we sought to find novel bacterial and metabolic hallmarks for bacterial vaginosis (BV). We studied the vaginal microbiome and metabolome of vaginal fluids from BV-affected patients (n = 43) and healthy controls (n = 37) by means of an integrated approach based on quantitative polymerase chain reaction (qPCR) and proton nuclear magnetic resonance ((1)H-NMR). The correlations between the clinical condition and vaginal bacterial communities were investigated by principal component analysis (PCA). To define the metabolomics signatures of BV, 100 discriminant analysis by projection on latent structure (PLS-DA) models were calculated. Bacterial signatures distinguishing the health condition and BV were identified by qPCR. Lactobacillus crispatus strongly featured the healthy vagina, while increased concentrations of Prevotella, Atopobium and Mycoplasma hominis specifically marked the infection. (1)H-NMR analysis has led to the identification and quantification of 17 previously unreported molecules. BV was associated with changes in the concentration of metabolites belonging to the families of amines, organic acids, short chain fatty acids, amino acids, nitrogenous bases and monosaccharides. In particular, maltose, kynurenine and NAD(+) primarily characterised the healthy status, while nicotinate, malonate and acetate were the best metabolic hallmarks of BV. This study helps to better understand the role of the vaginal microbiota and metabolome in the development of BV infection. We propose a molecular approach for the diagnosis of BV based on quantitative detection in the vaginal fluids of Atopobium, Prevotella and M. hominis, and nicotinate, malonate and acetate by combining qPCR and (1)H-NMR.

The genital tract and rectal microbiomes: their role in HIV susceptibility and prevention in women

“…The human microbiome, including the vaginal ecosystem, executes a wide range of metabolic activities, producing a plethora of metabolites in the process, which may underlie important microbe‐host driven mechanisms distinguishing phenotypic traits. Advancements in both targeted and comprehensive untargeted metabolomics have already provided evidence for divergent metabolic activity associated with vaginal dysbiotic states, including abnormalities in sugar compound, short chain fatty acid, lipid, biogenic amine and amino acid metabolism . However, little is known about vaginal metabolic profile disturbances in the context of STIs or metabolite biomarkers that may be associated with infection risk .…”

Metabolomics as a clinical testing method for the diagnosis of vaginal dysbiosis

“…The increasing availability of new analytical tools, providing a highly specific detection of various biomarkers, contributes to the development of genomics, proteomics, metabolomics, and transcriptomics . Through production of a molecular catalog and comparing metabolic data from healthy and non‐healthy individuals, a statistically significant difference in specific biomarkers between groups can lead to the detection of certain conditions …”

“…Vitali et al correlated vaginal colonization with metabolic profiles to determine possible biomarkers of BV. They identified 17 unreported small molecules associated with BV, including various amines, amino acids, and monosaccharides.…”

Accurate measurement of female genital tract fluid dilution in cervicovaginal lavage samples

“…CVL samples from women volunteers have been analyzed to determine whether topical zinc deficiency is a risk factor in recurrent vulvovaginal candidiasis [21] and if dissolved nitric oxide gas is associated with bacterial vaginosis (BV) [22]. CVL samples even have been used to isolate bacterial DNA in culture-independent vaginal microbiome studies [23, 24] and metabolomics studies [25, 26]. The concentration of antiviral agents is measured in CVL samples as part of pharmacokinetic studies aimed at developing regimens for the prevention of vaginal HIV-1 [27-32] and HSV-2 [29, 33] infection.…”