Article Text
Abstract
Introduction Recent studies have reported associations between bacterial vaginosis (BV) and cervicovaginal HPV. To obtain further insight into this relationship, we examined the vaginal microbiota and metabolome of women who were HPV+ and HPV-.
Methods Thirty-nine women self-collected mid-vaginal swabs that were profiled for bacterial composition by 16S rRNA gene amplicon sequencing, metabolites by both GC/MS and LC/MS-based metabolomics and 37 types of HPV DNA with the Roche HPV Linear Array genotyping test. Data were analysed by multiple linear regression controlling for confounding factors, as well as principal components analysis, partial least squares discriminatory analysis and linear discriminant analyses. All reported results have an adjusted p-value (q-value) <0.05.
Results Vaginal microbiota were clustered into community state types CST-I (L. crispatus-dominated), CST-III (L. iners-dominated) and CST-IV (low-Lactobacillus/BV-associated taxa). Overall, HPV+ women had higher polyamine and phospholipid concentrations than HPV- women in a model which controlled for CST and smoking status. Significant differences in metabolomic profiles of HPV+ and HPV- women were also evident in each stratum of CST. Among women who were CST-III, HPV+ women had higher concentrations of biogenic amines and glycogen-related metabolites compared to HPV- women. Within CST-IV, HPV+ women had lower concentrations of glutathione, glycogen, and phospholipid-related metabolites than HPV- women. Women with high-risk HPV strains had lower concentrations of amino acids, lipids and peptides compared to women who were hrHPV-.
Conclusion Detection of HPV was associated with altered vaginal concentrations of biogenic amines, glutathione and lipid-related metabolites. Reduced glutathione and oxidised glutathione have known associations with HPV and may be representative of increased oxidative stress and total glutathione depletion. Elucidating a causal relationship between microbial metabolites associated with increased oxidative stress and HPV infection warrants further investigation.