Without MC1R RNAi. LPS:5 ng/ml, IFN-c:10 ng/ml, a-MSH: 10 mM, and (CKPV)2 (0.1, 1 and 5 mM) (B ). The supernatant of the above macrophages were collected and added to L929 cells, after 20 hours, cell viability was measured by MTT assay, the inhibitory rate was calculated by 100 -cell viability OD of treatment group/cell viability OD of untreated control group (A). *p,0.01 (ANOVA). Experiments in this figure were repeated three times and similar results were obtained. doi:10.1371/journal.pone.0056004.g(CKPV)2 Inhibits Candida albicans Vaginitisarginase activity and the secretion of IL-10 to favor a macrophage M1 to M2 polarization.Anti-acute Inflammatory Effects of (CKPV)Above results confirmed the potential anti-fungal effects of CKPV)2, we also tested (CKPV)2’s potential role in other inflammation models including mouse ear edema, rat paw edema and rat foot itching (see protocol in text S1). Results were included in Fig. S1. The mice right ears became evident swelling and flare after xylene administration. Dexamethasone, a-MSH and (CKPV)2 significantly suppressed these inflammation reactions (Fig. S1-A). Subcutaneous injection of albumen into right paw caused immediate and persistent edema with the peak at 0.5 h?1 h. Dexamethasone, a-MSH and (CKPV)2 (high and middle doses) relieved paw edema (Fig. S1-B). Phosphate-induced itching was also blocked by dexamethasone, a-MSH and (CKPV)2 (high and middle doses) (Fig. S1-C), these results together suggest that (CKPV)2 could effectively prevent above acute inflammations.Discussion and ConclusionsOur results showed that (CKPV)2 dose-dependently inhibited Candida albicans colonies formation. In a rat Candida albicans vaginitis model, (CKPV)2 administration significantly inhibited vaginal Candida albicans survival and induced macrophage M2 polarization. (CKPV)2 inhibited Candida albicans phagocytosis by primary cultured macrophages. Further, (CKPV)2 promoted macrophages cAMP production through activating MC1R. In macrophages, (CKPV)2 administration inhibited the production of pro-inflammatory cytokines including TNF-a, IL-1b and IL-6, while increasing arginase activity and the secretion of antiinflammatory cytokines (IL-10), favoring a M1 to M2 polarization. These effects by (CKPV)2 on macrophages were almost reversed by MC1R siRNA knockdown. Our evidence suggest that the synthetic melanocortin (CKPV)2 exerts both anti-fungal and antiinflammatory activities 18325633 against Candida albicans vaginitis, probably through regulating macrophages M1 to M2 polarization. Local immunity plays a decisive role in the vaginal mucous Candida infections. Studies confirmed that the mice vaginal mucosa contained a large number of epithelial cells, dendritic cells, langerhans cells, neutrophils, macrophages and T cells [41]. Neutrophils are recognized as the dominant ones in I-BRD9 get Licochalcone-A innate immune cells of vagina. However, studies have indicated that neutrophils were not main ones to clear the yeast burden during the infection, although they have shown abilities of yeast phagocytosis [42]. Other innate immune cells such as monocytes and NK cells were also found in infected vaginal cavity [42]. Mononuclear cells can further differentiate into macrophages which play an important role in innate and adaptive immunity against microbial of host defense [40]. Monocytes/macrophages are able to “eat” extraneous pathogen, eliminate the aging and injured cells, destroy tumor cells and participate in immune responses [40]. Macrophages have.Without MC1R RNAi. LPS:5 ng/ml, IFN-c:10 ng/ml, a-MSH: 10 mM, and (CKPV)2 (0.1, 1 and 5 mM) (B ). The supernatant of the above macrophages were collected and added to L929 cells, after 20 hours, cell viability was measured by MTT assay, the inhibitory rate was calculated by 100 -cell viability OD of treatment group/cell viability OD of untreated control group (A). *p,0.01 (ANOVA). Experiments in this figure were repeated three times and similar results were obtained. doi:10.1371/journal.pone.0056004.g(CKPV)2 Inhibits Candida albicans Vaginitisarginase activity and the secretion of IL-10 to favor a macrophage M1 to M2 polarization.Anti-acute Inflammatory Effects of (CKPV)Above results confirmed the potential anti-fungal effects of CKPV)2, we also tested (CKPV)2’s potential role in other inflammation models including mouse ear edema, rat paw edema and rat foot itching (see protocol in text S1). Results were included in Fig. S1. The mice right ears became evident swelling and flare after xylene administration. Dexamethasone, a-MSH and (CKPV)2 significantly suppressed these inflammation reactions (Fig. S1-A). Subcutaneous injection of albumen into right paw caused immediate and persistent edema with the peak at 0.5 h?1 h. Dexamethasone, a-MSH and (CKPV)2 (high and middle doses) relieved paw edema (Fig. S1-B). Phosphate-induced itching was also blocked by dexamethasone, a-MSH and (CKPV)2 (high and middle doses) (Fig. S1-C), these results together suggest that (CKPV)2 could effectively prevent above acute inflammations.Discussion and ConclusionsOur results showed that (CKPV)2 dose-dependently inhibited Candida albicans colonies formation. In a rat Candida albicans vaginitis model, (CKPV)2 administration significantly inhibited vaginal Candida albicans survival and induced macrophage M2 polarization. (CKPV)2 inhibited Candida albicans phagocytosis by primary cultured macrophages. Further, (CKPV)2 promoted macrophages cAMP production through activating MC1R. In macrophages, (CKPV)2 administration inhibited the production of pro-inflammatory cytokines including TNF-a, IL-1b and IL-6, while increasing arginase activity and the secretion of antiinflammatory cytokines (IL-10), favoring a M1 to M2 polarization. These effects by (CKPV)2 on macrophages were almost reversed by MC1R siRNA knockdown. Our evidence suggest that the synthetic melanocortin (CKPV)2 exerts both anti-fungal and antiinflammatory activities 18325633 against Candida albicans vaginitis, probably through regulating macrophages M1 to M2 polarization. Local immunity plays a decisive role in the vaginal mucous Candida infections. Studies confirmed that the mice vaginal mucosa contained a large number of epithelial cells, dendritic cells, langerhans cells, neutrophils, macrophages and T cells [41]. Neutrophils are recognized as the dominant ones in innate immune cells of vagina. However, studies have indicated that neutrophils were not main ones to clear the yeast burden during the infection, although they have shown abilities of yeast phagocytosis [42]. Other innate immune cells such as monocytes and NK cells were also found in infected vaginal cavity [42]. Mononuclear cells can further differentiate into macrophages which play an important role in innate and adaptive immunity against microbial of host defense [40]. Monocytes/macrophages are able to “eat” extraneous pathogen, eliminate the aging and injured cells, destroy tumor cells and participate in immune responses [40]. Macrophages have.