Metabolic profile and disordered glycerophospholipid metabolism in recurrent vulvovaginal candidiasis

Recurrent vulvovaginal candidiasis (RVVC) takes a toll not only on women's reproductive system but also on patients' life quality. The pathogenesis is still not fully understood. This study sought to explore metabolic profile of vaginal discharge from RVVC patients using non-targeted metabolomics and investigate potential bioactive functions of metabolites. The metabolic spectrum of RVVC patients was remarkably distinguished from healthy control and VVC patients. 324 metabolites with significant difference were detected in RVVC compared with control group, of which 239 were upregulated and 85 were downregulated. Moreover, compared with VVC, RVVC had a total of 67 significantly different metabolites including 43 upregulated metabolites and 24 downregulated metabolites. KEGG pathway analysis showed that Glycerophospholipid (GPL) metabolic pathway and PPAR signaling pathway were significantly changed in RVVC and the metabolites enriched into GPL metabolic pathway including LysoPC(18:1(11Z)), LysoPC(20:3(5Z,8Z,11Z)), PC(16:0/20:2(11Z,14Z)), PC(18:1(11Z)/18:1(9Z)) and PE(22:2(13Z,16Z)/18:3(9Z,12Z,15Z)) were significantly changed in RVVC patients and of high AUC values. In addition, the highest increased LysoPS(18:1(9Z)/0:0) in RVVC was demonstrated to not only inhibit the proliferation and migration of vaginal epithelial cells but also promote apoptosis. Molecular docking which showed strongly bind between LysoPS(18:1(9Z)/0:0) and PPAR-γ lead to a hypothesis that LysoPS(18:1(9Z)/0:0) may have an influence on RVVC through PPAR signaling pathway. Our findings provide new perspectives in understanding the pathogenesis of RVVC.