Artemisia princeps Pamp. Essential Oil and Its Constituents Eucalyptol and α-terpineol Ameliorate Bacterial Vaginosis and Vulvovaginal Candidiasis in Mice by Inhibiting Bacterial Growth and NF-κB Activation

To investigate the inhibitory effects of Artemisia princeps Pamp. (family Asteraceae) essential oil (APEO) and its main constituents against bacterial vaginosis and vulvovaginal candidiasis, their antimicrobial activities against Gardnerella vaginalis and Candida albicans in vitro and their anti-inflammatory effects against G. vaginalis-induced vaginosis and vulvovaginal candidiasis were examined in mice. APEO and its constituents eucalyptol and alpha-terpineol were found to inhibit microbe growths. alpha-Terpineol most potently inhibited the growths of G. vaginalis and C. albicans with MIC values of 0.06 and 0.125% (v/v), respectively. The antimicrobial activity of alpha-terpineol was found to be comparable to that of clotrimazole. Intravaginal treatment with APEO, eucalyptol, or alpha-terpineol significantly decreased viable G. vaginalis and C. albicans numbers in the vaginal cavity and myeloperoxidase activity in mouse vaginal tissues compared with controls. These agents also inhibited the expressions of proinflammatory cytokines (IL-1 beta, IL-6, TNF-alpha), COX-2, iNOS, and the activation of NF-kappa B and increased expression of the anti-inflammatory cytokine IL-10. In addition, they inhibited the expressions of proinflammatory cytokines and the activation of NF-kappa B in lipopolysaccharide-stimulated peritoneal macrophages, and alpha-terpineol most potently inhibited the expressions of proinflammatory cytokines and NF-kappa B activation. Based on these findings, APEO and its constituents, particularly alpha-terpineol, ameliorate bacterial vaginosis and vulvovaginal candidiasis by inhibiting the growths of vaginal pathogens and the activation of NF-kappa B.