Development of a New Biomarker Model for Predicting Preterm Birth in Cervicovaginal Fluid

Abstract

Preterm birth (PTB) is a social problem that adversely affects not only the survival rate of the fetus, but also the premature babies and families, so there is an urgent need to find accurate biomarkers. We noted that among causes, eubiosis of the vaginal microbial community to dysbiosis leads to changes in metabolite composition. In this study, short chain fatty acids (SCFAs) representing dysbiosis were derivatized using (N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide, MTBSTFA) and targeted analysis was conducted in extracted organic phases of cervicovaginal fluid (CVF). In residual aqueous CVF, polar metabolites produced biochemistry process were derivatized using methoxyamine and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), and non-targeted analysis were conducted. Nine SCFAs were quantified, and 58 polar metabolites were detected in 90 clinical samples using gas chromatography/mass spectrometry (GC/MS). The criteria of statistical analysis and detection rate of clinical sample for development of PTB biomarkers were presented, and 19 biomarkers were selected based on it, consisting of 1 SCFA, 2 organic acids, 4 amine compounds, and 12 amino acids. In addition, the model was evaluated as a suitable indicator for predicting PTB without distinction between sample collection time. We hope that the developed biomarkers based on microbiota-derived metabolites could provide useful diagnostic biomarkers for actual patients and pre-pregnancy.

Lipidomic Analysis of Cervicovaginal Fluid for Elucidating Prognostic Biomarkers and Relevant Phospholipid and Sphingolipid Pathways in Preterm Birth

“…The selected lipid biomarkers were significantly reduced in PTB conditions ( Figure 6 ). According to the results of previous research in our laboratory, polar metabolites increase in PTB [ 28 ], but most of the lipid biomarkers tend to decrease in PTB. Among the phospholipids selected as biomarkers, not only PCs and PEs, but also PlsPCs and PlsPEs, were decreased in preterm birth.…”

“…Internal standards solution of diacylglycerol (DG, 10:0/10:0), triacylglycerol (TG, 17:0/17:0/17:0), phosphatidylcholine (PC, 10:0/10:0), phosphatidylethanolamine (PE, 10:0/10:0), sphingomyelin (SM, 18:1d/17:0), and ceramide (CER, C17) were diluted with isopropyl alcohol (5 mg/L) and spiked in 30 µL of each CVF sample. The mixed samples were extracted by modified Folch’s method, as described in a previous study [ 28 , 29 , 30 , 31 ]. 300 µL of cold MeOH/CHCl 3 (1:2, v / v ) was added to the CVF sample, and the mixture was sonicated (Daihan Scientific, Seoul, Republic of Korea) for 30 min.…”

Identification of Short-Chain Fatty Acids for Predicting Preterm Birth in Cervicovaginal Fluid Using Mass Spectrometry

“…Ten microliters of N - tert -butyldimethylsilyl- N -methyltrifluoroacetamide (MTBSTFA) along with 1% tert- butyldimethylchlorosilane reagent was added to the vial, derivatized at 80 °C for 30 min, and then cooled at room temperature for 20 min. The final solution was then injected into the GC–MS instrument ( Figure 4 ) [ 30 ].…”

Profiling of vaginal Lactobacillus jensenii isolated from preterm and full-term pregnancies reveals strain-specific factors relating to host interaction

“…This makes it challenging to develop biomarkers for preterm/dysbiotic conditions. Recent studies have shown vaginal metabolites and microbiome profiles could be useful in predicting preterm [55,56]. However, the mechanistic understanding of vaginal microbial genomic factors is needed to develop standard molecular based biomarkers that could aid in early PTB detection.…”