Progress in lactic acid-mediated maintenance of healthy vaginal microecology

Lactic acid is the main substance produced by Lactobacillus and plays an important role in maintaining a healthy vaginal microecology. Recent studies indicates that both L- and D-chiral isomers of lactic acid can be protonated and destroy the cell membranes of pathogens, thereby inhibiting bacterial vaginosis- and aerobic vaginitis-related pathogens. Lactic acid also can inhibit the pathogens of sexually transmitted diseases such as Chlamydia trachomatis and human immunodeficiency virus. Moreover, lactic acid acts as an immunomodulator to inhibit the inflammatory responses caused by pathogenic microorganisms and as an epigenetic regulator regulating gene expression in vaginal epithelial cells. In this paper, we reviewed the progress in lactic acid-mediated maintenance of a healthy vaginal microbiology in recent years for providing reference for further research. Key words: Lactobacillus; Lactic acid; Pathogen; Immunomodulator; Vaginal microecology