Vulvovaginal candidiasis: Epidemiology, microbiology and risk factors

Effect of the Pulsatilla decoction n-butanol extract on vulvovaginal candidiasis caused by Candida glabrata and on its virulence factors

Vulvovaginal candidiasis (VVC) caused by Candida glabrata (C. glabrata) is more persistent and resistant to treatment than when caused by Candida albicans (C. albicans) and has been on the rise in recent years. The n-butanol extract of Pulsatilla Decoction (BEPD) has been shown to be effective in treating VVC caused by C. glabrata, but the underlying mechanism of action remains unclear. In this study, the experimenter conducted in vitro and in vivo experiments to explore the effects of BEPD on the virulence factors of C. glabrata, as well as its efficacy, with a focus on possible immunological mechanism in VVC caused by C. glabrata. The contents of Anemoside B4, Epiberberine, Berberine, Aesculin, Aesculetin, Phellodendrine and Jatrorrhizine in BEPD, detected by high-performance liquid chromatography, were 31,736.64, 13,529.66, 105,143.72, 19,406.20, 4952.67, 10,317.03, 2489.93 μg/g, respectively. In vitro experiments indicated that BEPD moderately inhibited the growth of C. glabrata, its adhesion, and biofilm formation, and affected the expression of efflux transporters in the biofilm state. In vivo experiments demonstrated that BEPD significantly reduced vaginal inflammatory manifestation and the release of proinflammatory cytokines and LDH in mice with VVC caused by C. glabrata. Moreover, it inhibited the Phosphorylation of EGFR, ERK, P38, P65, and C-Fos proteins. The results suggested that although BEPD moderately inhibits the growth and virulence factors of C. glabrata in vitro, it can significantly reduce vaginal inflammation by down-regulating the EGFR/MAPK signaling pathway in mice with VVC infected by C. glabrata.

Candida albicans Infection Disrupts the Metabolism of Vaginal Epithelial Cells and Inhibits Cellular Glycolysis

Vulvovaginal candidiasis (VVC) is a common gynecologic disorder caused by fungal infections of the vaginal mucosa, with the most common pathogen being Candida albicans (C. albicans). Exploring metabolite changes in the disease process facilitates further discovery of targets for disease treatment. However, studies on the metabolic changes caused by C. albicans are still lacking. In this study, we used C. albicans-infected vaginal epithelial cells to construct an in vitro model of VVC, analyzed the metabolites by UHPLC-Q-Exactive MS, and screened the potential metabolites based on metabolomics. The results showed that C. albicans infection resulted in significant up-regulation of D-arabitol, palmitic acid, adenosine, etc.; significant down-regulation of lactic acid, nicotinamide (NAM), nicotinate (NA), etc.; and disruption of amino acid metabolism, and that these significantly altered metabolites might be potential therapeutic targets of VVC. Further experiments showed that C. albicans infection led to a decrease in glycolytic enzymes in damaged cells, inhibiting glycolysis and leading to significant alterations in glycolytic metabolites. The present study explored the potential metabolites of VVC induced by C. albicans infection based on metabolomics and verified the inhibitory effect of C. albicans on vaginal epithelial cell glycolysis, which is valuable for the diagnosis and treatment of VVC.

The effect of the female genital tract and gut microbiome on reproductive dysfunction

Microorganisms are ubiquitous in the human body; they are present in various areas including the gut, mouth, skin, respiratory tract, and reproductive tract. The interaction between the microbiome and reproductive health has become an increasingly compelling area of study. Disruption of the female genital tract microbiome can significantly impact the metabolism of amino acids, carbohydrates, and lipids, increasing susceptibility to reproductive tract diseases such as vaginitis, chronic endometritis, endometrial polyps, endometriosis, and polycystic ovary syndrome. The gut microbiome, considered an endocrine organ, plays a crucial role in the reproductive endocrine system by interacting with hormones like estrogen and androgens. Imbalances in the gut microbiome composition can lead to various diseases and conditions, including polycystic ovary syndrome, endometriosis, and cancer, although research on their mechanisms remains limited. This review highlights the latest advancements in understanding the female genital tract and gut microbiomes in gynecological diseases. It also explores the potential of microbial communities in the treatment of reproductive diseases. Future research should focus on identifying the molecular mechanisms underlying the association between the microbiome and reproductive diseases to develop new and effective strategies for disease prevention, diagnosis, and treatment related to female reproductive organs.

Pluronic F-127 Enhances the Antifungal Activity of Fluconazole against Resistant Candida Strains

Candida strains as the most frequent causes of infections, along with their increased drug resistance, pose significant clinical and financial challenges to the healthcare system. Some polymeric excipients were reported to interfere with the multidrug resistance mechanism. Bearing in mind that there are a limited number of marketed products with fluconazole (FLU) for the topical route of administration, Pluronic F-127 (PLX)/FLU formulations were investigated in this work. The aims of this study were to investigate (i) whether PLX-based formulations can increase the susceptibility of resistant Candida strains to FLU, (ii) whether there is a correlation between block polymer concentration and the antifungal efficacy of the FLU-loaded PLX formulations, and (iii) what the potential mode of action of PLX assisting FLU is. The yeast growth inhibition upon incubation with PLX formulations loaded with FLU was statistically significant. The highest efficacy of the azole agent was observed in the presence of 5.0 and 10.0% w/v of PLX. The upregulation of the CDR1/CDR2 genes was detected in the investigated Candida strains, indicating that the efflux of the drug from the fungal cell was the main mechanism of the resistance.

Longdan Xiegan decoction ameliorates vulvovaginal candidiasis by inhibiting the NLRP3 inflammasome via the Toll-like receptor /MyD88 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Longdan Xiegan decoction (LXD) is a standardized herbal prescription originally documented in the "Medical Formula Collection" by the eminent physician Wang Ang during the Qing dynasty. It has been used extensively to treat vulvovaginal candidiasis (VVC). However, despite its effectiveness, the mechanism of action remains unknown.

AIM OF THE STUDY

To elucidate the mechanism by which LXD relieves VVC via the Toll-like receptor/MyD88 pathway and activation of the NLRP3 inflammasome.

MATERIALS AND METHODS

Female Kunming mice (n = 96) were randomly divided into six groups: control, VVC model, LXD (10/20/40 mL/kg), and positive drug fluconazole. Mice were vaginally administered Candida albicans (C. albicans) solution (20 μL; 1 × 108 colony-forming units/mL), suspended for 5 min, and observed daily for changes in their condition. Continuous dilution was used to determine the number of colony-forming units. Gram, periodic acid-Schiff, Papanicolaou, and hematoxylin and eosin staining were used to determine the extent of infection. Enzyme-linked immunosorbent assay(ELISA) was used to determine the levels of proinflammatory cytokines IL-1β and IL-18. TLR2, TLR4, MyD88, NF-κB, NLRP3, ASC, and caspase-1 protein expression were determined using western blotting.

RESULTS

C. albicans infection destroyed the integrity of the vaginal mucosa, increased fungal burden and the influx of neutrophils into the vaginal cavity, and promoted the secretion of proinflammatory cytokines. C. albicans stimulated the expression of TLR2, TLR4, MyD88, NF-κB, NLRP3, ASC, and caspase-1 in vaginal tissue. Fungal burden, hyphal formation, and C. albicans adhesion were reduced in the 20 and 40 mL/kg LXD groups. Hematoxylin and eosin staining showed that inflammation was reduced and the stratum corneum had recovered in the 20 and 40 mL/kg LXD groups. LXD (20 and 40 mL/kg) significantly reduced IL-1β, IL-18 levels and the number of neutrophils in vaginal lavage and decreased TLR2, TLR4, MyD88, NF-κB, NLRP3, ASC, and caspase-1 expression.

CONCLUSIONS

This study systematically demonstrated the therapeutic effect of LXD on protein expression and pathological conditions in VVC mice. The results showed that LXD could eliminate the invasion of vaginal hyphae in mice, reduce the recruitment of neutrophils, and reduce the expression of TLR/MyD88 pathway-related proteins and NLRP3 inflammasome. The above results clearly indicate that LXD may profoundly regulate NLRP3 inflammasome through the TLR/MyD88 pathway and play a therapeutic role in VVC.

Oteseconazole versus fluconazole for the treatment of severe vulvovaginal candidiasis: a multicenter, randomized, double-blinded, phase 3 trial

Vulvovaginal candidiasis (VVC) is a common condition among women. Fluconazole remains the dominant treatment option for VVC. Oteseconazole is a highly selective inhibitor of fungal CYP51. This randomized, double-blinded, phase 3 trial was conducted to evaluate the efficacy and safety of oteseconazole compared with fluconazole in treating severe VVC. Female subjects presenting with vulvovaginal signs and symptoms score of ≥7 and positive Candida infection determined by potassium hydroxide test or Gram staining were randomly assigned to receive oteseconazole (600 mg on D1 and 450 mg on D2) or fluconazole (150 mg on D1 and D4) in a 1:1 ratio. The primary endpoint was the proportion of subjects achieving therapeutic cure [defined as achieving both clinical cure (absence of signs and symptoms of VVC) and mycological cure (negative culture of Candida species)] at D28. A total of 322 subjects were randomized and 321 subjects were treated. At D28, a statistically significantly higher proportion of subjects achieved therapeutic cure in the oteseconazole group than in the fluconazole group (66.88% vs 45.91%; P = 0.0002). Oteseconazole treatment resulted in an increased proportion of subjects achieving mycological cure (82.50% vs 59.12%; P < 0.0001) and clinical cure (71.25% vs 55.97%; P = 0.0046) compared with fluconazole. The incidence of treatment-emergent adverse events was similar between the two groups. No subjects discontinued study treatment or withdrew study due to adverse events. Oteseconazole showed statistically significant and clinically meaningful superiority over fluconazole for the treatment of severe VVC and was generally tolerated.

The role of probiotics in women's health: An update narrative review

Probiotics, live microorganisms that confer health benefits to the host when administered in adequate amounts, have gained considerable attention for their potential role in maintaining women's health. This overview summarizes key clinical findings on the beneficial effects of probiotics in various aspects of women's health. Probiotics, particularly Lactobacillus species, contribute to vaginal health by promoting a balanced vaginal microbiome to prevent infections and maintain an acidic environment. In gynecologic conditions, probiotics show potential in preventing and managing bacterial vaginosis, vulvovaginal candidiasis, and sexually transmitted infections. Probiotic supplementation has also been associated with improvements in metabolic parameters and menstrual irregularities in polycystic ovary syndrome patients. During pregnancy, probiotics may be helpful in reducing the risk of gestational diabetes, maternal group B streptococcal colonization, obstetric anemia, and postpartum mastitis. In recent years, the potential role of probiotics in the prevention and management of gynecologic cancer has gained attention. Further research is needed to better understand the specific mechanisms and determine the optimal Lactobacillus strains and dosages regimens for gynecologic cancer prevention and therapy. In conclusion, probiotics offer a non-invasive and cost-effective approach to support women's health and prevent obstetric and gynecologic complications.

Abnormal M1 polarization of placental macrophage induced by IL-15/STAT5 activation in VVC may lead to adverse pregnancy outcomes

Pregnant women with vulvovaginal candidiasis (VVC) may experience adverse pregnancy outcomes such as premature delivery, intrauterine infection, abortion, and neonatal infection. Therefore, finding new treatments for VVC in pregnancy is a public health priority. We aimed to study the adverse consequences of Candida albicans (C. albicans) vaginal infection in pregnant mice and explore the mechanisms by which C. albicans affects macrophages. Our findings contribute to the development of new approaches to treat VVC during pregnancy. We established an animal model of vaginal infection by C. albicans in pregnant mice and observed adverse pregnancy outcomes such as decreased body weight, reduced implantation number, and increased abortion rates. Additionally, we infected mouse macrophage line RAW264.7 cells with C. albicans and established a cell model. We employed RT-qPCR, Western blot, and immunofluorescence staining to verify the changes in the IL-15/STAT5 signaling pathway and the role it played on the M1 polarization of C. albicans-infected macrophages at both the gene and protein levels. Our results indicate that the adverse pregnancy outcomes in VVC may be linked to changes in the IL-15/STAT5 pathway induced by C. albicans, which could impact macrophage M1 polarization.

Loop-Mediated Isothermal Amplification (LAMP): Potential Point-of-Care Testing for Vulvovaginal Candidiasis

PURPOSE

The aim of this study is to establish a loop-mediated isothermal amplification (LAMP) method for the rapid detection of vulvovaginal candidiasis (VVC).

METHODS

We developed and validated a loop-mediated isothermal amplification (LAMP) method for detecting the most common Candida species associated with VVC, including C. albicans, N. glabratus, C. tropicalis, and C. parapsilosis. We evaluated the specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), and Kappa value of the LAMP method to detect different Candida species, using the conventional culture method and internal transcribed spacer (ITS) sequencing as gold standards and smear Gram staining and real-time Rolymerase Chain Reaction (PCR) as controls.

RESULTS

A total of 202 cases were enrolled, of which 88 were VVC-positive and 114 were negative. Among the 88 positive patients, the fungal culture and ITS sequencing results showed that 67 cases (76.14%) were associated with C. albicans, 13 (14.77%) with N. glabratus, 5 (5.68%) with C. tropicalis, and 3 (3.41%) with other species. Regarding the overall detection rate, the LAMP method presented sensitivity, specificity, PPV, NPV, and Kappa values of 90.91%, 100%, 100%, 93.4%, and 0.919, respectively. Moreover, the LAMP had a specificity of 100% for C. albicans, N. glabratus, and C. tropicalis, with a sensitivity of 94.03%, 100%, and 80%, respectively. Moreover, the microscopy evaluation had the highest sensitivity, while the real-time PCR was less specific for C. albicans than LAMP. In addition, CHROMagar Candida was inferior to LAMP in detecting non-albicans Candida (NAC) species.

CONCLUSIONS

Based on the cost-effective, rapid, and inexpensive characteristics of LAMP, coupled with the high sensitivity and specificity of our VVC-associated Candida detection method, we provided a possibility for the point-of-care testing (POCT) of VVC, especially in developing countries and some laboratories with limited resources.

Phenotypic characterization and antifungal susceptibility profile of Candida isolates from women with vulvovaginal candidiasis at a community health center linked to a teaching institution in the Sub-Himalayan region of North India

Introduction

Vulvovaginal candidiasis (VVC) is considered a common gynecological problem among females of reproductive age group. 70-75% of women report having had candidal vulvovaginitis at some point in their lifetimes and 40-50% suffer recurrent candidal vulvovaginitis.

Objectives

This study aims to identify the Candida species involved in VVC and to determine their antifungal susceptibility pattern.

Materials and Methods

The present study was a cross-sectional study conducted on 257 females (18-55 yr) with complaints of abnormal vaginal discharge. For detection of Candida, the swab samples were subjected to Gram stain, 10% KOH mount, and culture on Sabouraud dextrose agar (SDA). Candida species identification was done by subculturing Candida isolates onto CHROMagar, corn meal agar (Himedia), and further confirmation was done by MALDI-TOF MS. Antifungal testing was done using the disk diffusion method.

Results

A total of 257 females with complaints of abnormal discharge were enrolled in this study. Out of 257, C. albicans 37 (58.7%) and 26 (41.3%) isolates were identified as non-albicans Candida. Out of 63 positive cases, a maximum number of study subject belongs to the age group 26-35 years (50.8%). Along with vaginal discharge, itching (65.37%) is the most common complaint. VVC was found to be most predominant in patients with prolonged antibiotic therapy (38.1%), and in pregnant females (15.9%).

Conclusion

Understanding the emerging fungal pathogens and their drug susceptibility patterns is essential for the effective management of infections. Drug resistance can lead to treatment failure and highlights the need for alternative treatment options or strategies.

Antifungal Activity of Bulgarian Rose Damascena Oil against Vaginitis-Causing Opportunistic Fungi

Since Bulgarian rose damascena oil is known for its anti-inflammatory, antioxidant, and antimicrobial properties, we investigated its antifungal activity against the species of Candida, which are among the most common opportunistic fungal pathogens. Our disk-diffusion assay revealed that Bulgarian rose damascena oil effectively inhibited the growth of Candida albicans along with various bacteria. The minimum inhibitory and fungicidal concentrations against Candida albicans and Candida glabrata were all 0.25%. Under our experimental conditions, Bulgarian rose damascena oil showed better inhibitory effects on Candida glabrata and Candida albicans than several popular essential oils reported to have antifungal activity other than Origanum vulgare oil. Interestingly, Bulgarian rose damascena oil showed better antifungal activity against Candida species at acidic pH and induced cell death of Candida species in the culture medium, with cell death seen in 25-35% of the cells exposed to 0.05% Bulgarian rose damascena oil. Furthermore, Bulgarian rose damascena oil inhibited the hyphal growth of Candida albicans cultured in the RPMI medium with fetal bovine serum. These findings collectively suggest that Bulgarian rose damascena oil has antifungal activity against Candida species and thus could potentially be developed in novel therapies for vaginitis-causing pathogenic fungi.

Limosilactobacillus reuteri 29A Cell-Free Supernatant Antibiofilm and Antagonistic Effects in Murine Model of Vulvovaginal Candidiasis

Vaginal dysbiosis advocates burgeoning of devious human vaginal pathobionts like Candida species that possess multiple virulence properties and metabolic flexibility to cause infections. Inevitably, antifungal resistance may emerge due to their innate nature (e.g., biofilm formation), which assists in their virulence as well as the formation of persister cells after dispersal. In consequence, the phenomenon of biofilm involvement in vulvovaginal candidiasis (VVC) and its recurrence is becoming paramount. Lactic acid bacteria and their derivatives have proven to be hostile to Candida species. Here, we throw more light on the potency of the derivatives, i.e., cell-free supernatant (CFS) produced by an indigenously isolated vaginal Lactobacillus strain, Limosilactobacillus reuteri 29A. In the present study, we investigated the antibiofilm and antagonistic effects of L. reuteri 29A CFS, against biofilms of Candida species and in murine model of vulvovaginal candidiasis. In our in vitro biofilm study, the CFS disrupted and inhibited preformed biofilms of C. albicans and C. glabrata. Scanning electron microscopy displayed the destruction of preformed biofilms and impediment of C. albicans morphogenesis by the CFS. Gas chromatography-mass spectrometry analysis showed multiple key compounds that may act singly or synergistically. In vivo, the CFS showed no collateral damage to uninfected mice; the integrity of infected vaginal tissues was restored by the administration of the CFS as seen from the cytological, histopathological, and electron microscopical analyses. The results of this study document the potential use of CFS as an adjuvant or prophylactic option in addressing vaginal fungal infections.

Antifungal Activity and Type of Interaction of Melissa officinalis Essential Oil with Antimycotics against Biofilms of Multidrug-Resistant Candida Isolates from Vulvovaginal Mucosa

(1) Background: Vulvovaginal candidosis (VVC) is a major therapy issue due to its high resistance rate and virulence factors such as the ability to form biofilms. The possibility of combining commonly used antifungals with natural products might greatly improve therapeutic success. (2) Methods: A total of 49 vulvovaginal isolates, causative agents of recurrent VVC, were tested for their susceptibility to fluconazole, nystatin, and Melissa officinalis essential oil (MOEO). This examination included testing the antibiofilm potential of antifungals and MOEO and the determination of their types of interaction with mature biofilms. (3) Results: Antimicrobial testing showed that 94.4% of the Candida albicans isolates and all the Candida krusei isolates were resistant to fluconazole, while all strains showed resistance to nystatin. The same strains were susceptible to MOEO in 0.156-2.5 mg/mL concentrations. Additionally, the results revealed very limited action of fluconazole, while nystatin and MOEO reduced the amount of biofilm formed by as much as 17.7% and 4.6%, respectively. Testing of the combined effect showed strain-specific synergistic action. Furthermore, the lower concentrations exhibited antagonistic effects even in cases where synergism was detected. (4) Conclusions: This study showed that MOEO had a very good antibiofilm effect. However, combining MOEO with antimycotics demonstrated that the type of action depended on the choice of antifungal drugs as well as the applied concentration.

Species identification, antifungal susceptibility patterns, and vitamin D3 level in women with vaginal candidiasis: a case-control study in Iran

Vulvovaginal candidiasis (VVC) is a fungal infection that is a global issue of women's health due to its association with morbidity, infertility, and economic costs. This study aimed to compare the vitamin D3 levels between women with VVC to healthy controls and determine the species distribution and susceptibility pattern of isolates. Species identification was performed using sequencing of the ITS-rDNA regions and amplification of the HWP1 gene. Antifungal susceptibility testing was determined by the disk diffusion method. Moreover, serum vitamin D3 levels were measured using a commercial ELISA (enzyme-linked immunosorbent assay) kit. Our results indicated that vitamin D3 level in women with VVC was lower than those of healthy women (p-value < .001). Candida albicans complex (62.8 percent) was the most common species, and most species were susceptible to fluconazole, itraconazole, ketoconazole, and nystatin. In conclusion, our study revealed a potential link between vitamin D3 deficiency and VVC in women. Although our findings showed significantly lower vitamin D3 levels in women with VVC, further research is needed to establish a definitive causative relationship between vitamin D3 deficiency and VVC. Nonetheless, our study highlights the potential importance of maintaining adequate levels of vitamin D3 and the need for further exploration in this area.

Molecular association of Candida albicans and vulvovaginal candidiasis: focusing on a solution

Candida albicans-mediated vulvovaginal candidiasis (VVC) is a significant challenge in clinical settings, owing to the inefficacy of current antifungals in modulating virulence, development of resistance, and poor penetration into the biofilm matrix. Various predisposition factors are molecular drivers that lead to the dysbiosis of normal microflora of the vagina, upregulation of central metabolic pathways, morphogenesis, hyphal extension, adhesion, invasion, and biofilm formation leading to chronic infection and recurrence. Hence, it is crucial to understand the molecular mechanism behind the virulence pathways driven by those drivers to decode the drug targets. Finding innovative solutions targeting fungal virulence/biofilm may potentiate the antifungals at low concentrations without affecting the recurrence of resistance. With this background, the present review details the critical molecular drivers and associated network of virulence pathways, possible drug targets, target-specific inhibitors, and probable mode of drug delivery to cross the preclinical phase by appropriate in vivo models.

Comparing the Effect of Probiotic and Fluconazole on Treatment and Recurrence of Vulvovaginal Candidiasis: a Triple-Blinded Randomized Controlled Trial

Vaginitis is a common problem in women. Candida albicans is responsible for more than 85% of vaginal fungal infections. The aim of this study was to compare the effects of probiotic and fluconazole on the treatment and recurrence of vulvovaginal candidiasis (VVC). This triple-blinded randomized controlled trial was conducted on 80 married women, aged 18-49 years, with VVC, as confirmed by clinical and laboratory diagnosis. The participants were allocated into two groups using blocked randomization method. The fluconazole-treated group received a single dose of fluconazole (150 mg) supplemented with 30 placebo capsules of probiotic, and the probiotic-treated group got 30 probiotic capsules containing 1 × 109 CFU/g LA-5 with 1 fluconazole placebo capsule. The samples were taken from patients to evaluate the vaginal pH and microbiological tests before, 30-35 days, and 60-65 days after starting the treatment. The signs and symptoms were assessed before the intervention and the first and second follow-ups. Chi-square, Fisher's exact, independent t, and ANCOVA tests were then used for data analysis. There was no statistically significant difference between the two groups (p = 0.127) in the frequency of negative culture 30-35 days after starting the treatment, but the frequency of negative culture 60-65 days after starting treatment in the fluconazole group was significantly higher than that of the probiotic group (p = 0.016). The abnormal discharge and vulvovaginal erythema in the first and second follow-ups and also pruritus in the second follow-up in the fluconazole group were significantly lower than those in the probiotic group (p < 0.05). There was, however, no statistically significant difference in burning, frequent urination, dysuria, and dyspareunia between the groups (p > 0.05). Lactobacillus acidophilus supplementation had an effect similar to that of fluconazole in treating most symptoms of VVC, but it was less effective than the latter in preventing recurrence. Trial Registration: Iranian Registry of Clinical Trials (IRCT): IRCT20110826007418N5. Date of registration: 3 March 2021; URL: https://en.irct.ir/trial/50819 ; Date of first registration: 10 March 2021.

Characterization of endoplasmic reticulum-associated degradation in the human fungal pathogen Candida albicans

Background

Candida albicans is the most prevalent human fungal pathogen. In immunocompromised individuals, C. albicans can cause serious systemic disease, and patients infected with drug-resistant isolates have few treatment options. The ubiquitin-proteasome system has not been thoroughly characterized in C. albicans. Research from other organisms has shown ubiquitination is important for protein quality control and regulated protein degradation at the endoplasmic reticulum (ER) via ER-associated protein degradation (ERAD).

Methods

Here we perform the first characterization, to our knowledge, of ERAD in a human fungal pathogen. We generated functional knockouts of C. albicans genes encoding three proteins predicted to play roles in ERAD, the ubiquitin ligases Hrd1 and Doa10 and the ubiquitin-conjugating enzyme Ubc7. We assessed the fitness of each mutant in the presence of proteotoxic stress, and we used quantitative tandem mass tag mass spectrometry to characterize proteomic alterations in yeast lacking each gene.

Results

Consistent with a role in protein quality control, yeast lacking proteins thought to contribute to ERAD displayed hypersensitivity to proteotoxic stress. Furthermore, each mutant displayed distinct proteomic profiles, revealing potential physiological ERAD substrates, co-factors, and compensatory stress response factors. Among candidate ERAD substrates are enzymes contributing to ergosterol synthesis, a known therapeutic vulnerability of C. albicans. Together, our results provide the first description of ERAD function in C. albicans, and, to our knowledge, any pathogenic fungus.

Biofilm Formation and Aspartyl Proteinase Activity and Their Association with Azole Resistance Among Candida albicans Causing Vulvovaginal Candidiasis, Egypt

Background

Candida albicans (C. albicans) is a major cause of vulvovaginal candidiasis (VVC), a condition that is commonly treated with azole agents. Biofilm formation and aspartyl proteinase production are important virulence factors that could be linked to azole resistance in C. albicans impeding therapy.

Aim

To find out the association of both factors with azole resistance among C. albicans isolated from VVC cases in Egyptian nonpregnant women of childbearing age.

Patients and Methods

In a cross-sectional study, C. albicans was isolated from nonpregnant females diagnosed clinically as having VVC during a 1-year study period. Susceptibility to azole agents was tested using the disc diffusion method. Biofilm formation and aspartyl proteinase production were assessed phenotypically. Additionally, two biofilm-related genes (ALS1 and HWP1) and three proteinase genes (SAP2, SAP4, and SAP6) were screened for using polymerase chain reaction (PCR).

Results

Among 204 C. albicans isolates, azole resistance ratios were as follows: voriconazole (30.4%), itraconazole (17.6%), fluconazole (11.3%) and econazole (6.4%). Biofilm-producing capacity was detected in 63.2% of isolates, and 63.2% were proteinase producers. The frequencies of ALS1 and HWP1 were 69.6% and 74.5%, respectively, while SAP2, SAP4, and SAP6 were 69.2%, 88.7%, and 64.7%, respectively. Biofilm formation was significantly associated with azole resistance (P < 0.001 for each tested azole agent) as was proteinase production (P < 0.001 for fluconazole, voriconazole, and econazole resistance and P = 0.047 for itraconazole).

Conclusion

Among nonpregnant Egyptian women of childbearing age, azole resistance in C. albicans causing VVC is significantly associated with biofilm formation and proteinase production. The development of new therapeutic agents that can target these factors is warranted.

Vaginal homeostasis features of Vulvovaginal Candidiasis through vaginal metabolic profiling

Vulvovaginal candidiasis (VVC) is an inflammatory disease primarily infected by Candida albicans. The condition has good short-term treatment effects, high recurrence, and seriously affects the quality of life of women. Metabolomics has been applied to research a variety of inflammatory diseases. In the present study, the vaginal metabolic profiles of VVC patients and healthy populations (Cnotrol (CTL)) were explored by a non-targeted metabolomics approach. In total, 211 differential metabolites were identified, with the VVC group having 128 over-expressed and 83 under-expressed metabolites compared with healthy individuals. Functional analysis showed that these metabolites were mainly involved in amino acid metabolism and lipid metabolism. In addition, network software analysis indicated that the differential metabolites were associated with mitogen-activated protein kinase (MAPK) signaling and NF-κB signaling. Further molecular docking suggested that linoleic acid can bind to the acyl-CoA synthetase 1 (ACSL1) protein, which has been shown to be associated with multiple inflammatory diseases and is an upstream regulator of the MAPK and NF-κB signaling pathways that mediate inflammation. Therefore, our preliminary analysis results suggest that VVC has a unique metabolic profile. Linoleic acid, a significantly elevated unsaturated fatty acid in the VVC group, may promote VVC development through the ACSL1/MAPK and ACSL1/NF-κB signaling pathways. This study's findings contribute to further exploring the mechanism of VVC infection and providing new perspectives for the treatment of Candida albicans vaginal infection.

β-Estradiol and progesterone enhance biofilm development and persister cell formation in monospecies and microcosms biofilms derived from vulvovaginal candidiasis

The present study aimed to: (1) evaluate the influence of the steroid hormones (SH) on biofilm development; (2) investigate the formation of persister cells (PC) in biofilms; and (3) investigate the influence of SH on PC formation. Biofilms were derived from vulvovaginal candidiasis (VVC) samples and evaluated by three models: microcosm biofilms grown in Vaginal Fluid Simulator Medium (MiB-VFSM); monospecies biofilms grown in VFSM (MoB-VFSM) and RPMI media (MoB-RPMI). SH altered cell counting and biomass of biofilms grown in VSFM; MoB-RPMI were negatively affected by SH. SH stimulated the formation of PC in MiB-VFSM but not MoB-VFSM; MoB-RPMI showed a lower number of PC in the presence of SH. The results showed that SH altered the dynamics of biofilm formation and development, depending on the study model. The data suggest the influence of hormones on the physiology of Candida biofilms and reinforce the importance of PC in the pathogenesis of VVC.

The Association between Gestational Diabetes Mellitus and Infections in Pregnancy-Systematic Review and Meta-Analysis

We conducted a systematic review and meta-analysis to evaluate the association between gestational diabetes mellitus and infections during pregnancy. We included cross-sectional, case-control, cohort studies and clinical trials, evaluating the frequency of infections in women with and without gestational diabetes mellitus. A search was conducted in Embase, PubMed, and Web of Science electronic databases and by manually searching references, until 23 March 2022, resulting in 16 studies being selected for review, with 111,649 women in the gestational diabetes mellitus group, and 1,429,659 in the controls. Cochrane's Q test of heterogeneity and I² were used to assess heterogeneity. Pooled odds ratio (OR) was calculated. Funnel plots and Egger test were used for assessment of publication bias. The results showed a significant association between gestational diabetes mellitus and infections (pooled-OR 1.3 95% CI [1.2-1.5]). Sub-analyses showed a significant association for urinary tract infections (pooled-OR of 1.2 95% CI [1.1-1.3]), bacterial infections (pooled-OR were 1.2 95% CI [1.1-1.4]), and SARS-CoV-2 (pooled-OR 1.5 95% CI [1.2-2.0]) but not to gingivitis or vaginal candidiasis. The results underscore the significance of acknowledging gestational diabetes mellitus as a risk factor for infections.

Clinical Evaluation of Polymerase Chain Reaction Coupled with Quantum Dot Fluorescence Analysis for Diagnosis of Candida Infection in Vulvovaginal Candidiasis Practice

Purpose

Time-consuming culture methods and wet-mount microscopy (WMM) with low sensitivity have difficulties in diagnosing Vulvovaginal candidiasis (VVC). Rapid and highly sensitive polymerase chain reaction coupled with quantum dot fluorescence analysis (PCR-QDFA) for the diagnosis of VVC has not been reported to date. This study was the first to evaluate the performance of PCR-QDFA for diagnosis of Candida strains in the leukorrhea samples from patients with suspected VVC.

Patients and Methods

Leukorrhea samples from all visited patients were taken from the vagina using vaginal swabs by clinicians. We evaluated patients admitted with suspected VVC who completed WMM for diagnosis and reported the diagnostic effectiveness of PCR-QDFA and Candida culture (gold standard) when testing leucorrhea samples.

Results

A total of 720 leukorrhea samples from 387 VVC-positive patients and 333 VVC-negative patients were included in this study. Of the 387 leukorrhea samples from the VVC-positive patients, 391 Candida strains were identified by culture. 99.23% (388/391) Candida strains were included in the PCR-QDFA list. The 388 Candida strains belonged to four different species of Candida, including C. albicans (n = 273, 70.36%), C. glabrata (n = 85, 21.91%), C. tropicalis (n = 16, 4.12%), and C. krusei (n = 14, 3.61%). PCR-QDFA diagnosed Candida strains in 340/384 (88.54%) of the leucorrhea samples with Candida strains infection. The sensitivity of PCR-QDFA for C. albicans, C. glabrata, C. tropicalis, and C. krusei was 89.01%, 85.88%, 81.25% and 92.86%, respectively. The specificity of PCR-QDFA for C. albicans, C. glabrata, C. tropicalis and C. krusei was 93.69%, 99.37%, 99.71%, and 99.57%, respectively.

Conclusion

The highly sensitive and specific PCR-QDFA technique can be exploited as a rapid (approximately 4 h) diagnostic tool for common Candida strains of leucorrhea samples from patients with suspected VVC.

Gut fungal mycobiome: A significant factor of tumor occurrence and development

A variety of bacteria, viruses, fungi, protists, archaea and protozoa coexists within the mammalian gastrointestinal (GI) tract such as that fungi are detectable in all intestinal and colon segments in almost all healthy adults. Although fungi can cause infectious diseases, they are also related to gut and systemic homeostasis. Importantly, through transformation of different forms such as from yeast to hyphae, interaction among gut microbiota such as fungal and bacterial interaction, host factors such as immune and host derived factors, and fungus genetic and epigenetic factors, fungi can be transformed from commensal into pathogenic lifestyles. Recent studies have shown that fungi play a significant role in the occurrence and development of tumors such as colorectal cancer. Indeed, evidences have shown that multiple species of different fungi exist in different tumors. Studies have also demonstrated that fungi are related to the occurrence and development of tumors, and also survival of patients. Here we summarize recent advances in the transformation of fungi from commensal into pathogenic lifestyles, and the effects of gut pathogenic fungi on the occurrence and development of tumors such as colorectal and pancreatic cancers.

Vaginal Epithelial Cell Membrane-Based Phototherapeutic Decoy Confers a "Three-in-One" Strategy to Treat against Intravaginal Infection of Candida albicans

Phototherapy is an effective strategy to control Candida albicans (C. albicans) infection without raising the concern of drug resistance. Despite its effectiveness, a higher dose of phototherapeutic power is required for C. albicans elimination compared to bacteria that have to be used, which is readily accompanied by off-target heat and toxic singlet oxygen to damage normal cells, thus limiting its usefulness for antifungal applications. Here to overcome this, we develop a "three-in-one" biomimetic nanoplatform consisting of an oxygen-dissolved perfluorocarbon camouflaged by a photosensitizer-loaded vaginal epithelial cell membrane. With a cell membrane coating, the nanoplatform is capable of specifically binding with C. albicans at the superficial or deep vaginal epithelium, thereby centering the phototherapeutic agents on C. albicans. Meanwhile, the cell membrane coating endows the nanoplatform to competitively protect healthy cells from candidalysin-medicated cytotoxicity. Upon candidalysin sequestration, pore-forming on the surface of the nanoplatform accelerates release of the preloaded photosensitizer and oxygen, resulting in enhanced phototherapeutic power for improved anti-C. albicans efficacy under near-infrared irradiation. In an intravaginal C. albicans-infected murine model, treatment with the nanoplatform leads to a significantly decreased C. albicans burden, particularly when leveraging candidalysin for further elevated phototherapy and C. albicans inhibition. Also, the same trends hold true when using the nanoplatform to treat the clinical C. albicans isolates. Overall, this biomimetic nanoplatform can target and bind with C. albicans and simultaneously neutralize the candidalysin and then transform such toxins that are always considered a positive part in driving C. albicans infection with the power of enhancing phototherapy for improved anti-C. albicans efficacy.

Mycobiome Study Reveals Different Pathogens of Vulvovaginal Candidiasis Shape Characteristic Vaginal Bacteriome

Vulvovaginal candidiasis (VVC) can alter the vaginal microbiome composition and structure, and this may be correlated with its variable treatment efficacy. Integrated analysis of the mycobiome and bacteriome in VVC could facilitate accurate diagnosis of infected patients and further decipher the characterized bacteriome in different types of VVC. Our mycobiome analysis determined two common types of VVC, which were clustered into two community state types (CSTs) featured by Candida glabrata (CST I) and Candida albicans (CST II). Subsequently, we compared the vaginal bacteriome in two CSTs of VVC and two other types of reproductive tract infections (RTIs), bacterial vaginosis (BV) and Ureaplasma urealyticum (UU) infection. The vaginal bacteriome in VVC patients was between the healthy and other RTIs (BV and UU) status, it bore the greatest resemblance to that of healthy subjects. While BV and UU patients have the unique vaginal microbiota community structure, which very different with healthy women. Compared with CST II, the vaginal bacteriome of CST I VVC was characterized by Prevotella, a key signature in BV. In comparison, CST II was featured by Ureaplasma, the pathogen of UU. The findings of our study highlight the need for co-analysis and simultaneous consideration of vaginal mycobiome and bacteriome in the diagnosis and treatment of VVC to solve common clinical problems, such as unsatisfactory cure rates and recurrent symptoms. IMPORTANCE Fungi headed by C. albicans play a critical role in VVC but are not sufficient for its occurrence, indicating the involvement of other factors, such as the vaginal bacteriome. We found that different CST correspond to different bacterial composition in patients with VVC, and this could underlie the alteration of vaginal microorganism environment in VVC patients. We believe that this correlation should not be ignored, and it may be related to the unsatisfactory treatment outcomes and high recurrence rate of VVC. Here, we provided evidence for associations between vaginal bacteriome patterns and fungal infection. Screening specific biomarkers for three common RTIs paves a theoretical basis for further development of personalized precision treatment.

An Integrated and Multi-Target Nucleic Acid Isothermal Analysis System for Rapid Diagnosis of Vulvovaginal Candidiasis

Rapid identification of Candida species is significant for the diagnosis of vulvovaginal candidiasis (VVC). An integrated and multi-target system for the rapid, high-specificity, and high-sensitivity detection of four Candida species was developed. The system consists of a rapid sample processing cassette and a rapid nucleic acid analysis device. The cassette could process the Candida species to release nucleic acids in 15 min. The released nucleic acids were analyzed by the device as fast as within 30 min, using the loop-mediated isothermal amplification method. The four Candida species could be simultaneously identified, with each reaction using only 1.41 µL of reaction mixture, which was low cost. The RPT (rapid sample processing and testing) system could detect the four Candida species with high sensitivity (<2 CFU/reaction) and high specificity. The system also processed and analyzed 32 clinical samples, giving the results with high clinical sensitivity and specificity. Hence, the system was a significant and effective platform for the diagnosis of VVC. Furthermore, the period of validity of the reagents and chips used in the system was >90 days, and the system could also be used for the detection of bacteria.

Gardnerella Revisited: Species Heterogeneity, Virulence Factors, Mucosal Immune Responses, and Contributions to Bacterial Vaginosis

Gardnerella species are associated with bacterial vaginosis (BV) and have been investigated as etiological agents of the condition. Nonetheless, the isolation of this taxon from healthy individuals has raised important questions regarding its etiological role. Recently, using advanced molecular approaches, the Gardnerella genus was expanded to include several different species that exhibit differences in virulence potential. Understanding the significance of these different species with respect to mucosal immunity and the pathogenesis and complications of BV could be crucial to solving the BV enigma. Here, we review key findings regarding the unique genetic and phenotypic diversity within this genus, virulence factors, and effects on mucosal immunity as they stand. We also comment on the relevance of these findings to the proposed role of Gardnerella in BV pathogenesis and in reproductive health and identify key gaps in knowledge that should be explored in the future.

The Interplay between Candida albicans, Vaginal Mucosa, Host Immunity and Resident Microbiota in Health and Disease: An Overview and Future Perspectives

Vulvovaginal candidiasis (VVC), which is primarily caused by Candida albicans, is an infection that affects up to 75% of all reproductive-age women worldwide. Recurrent VVC (RVVC) is defined as >3 episodes per year and affects nearly 8% of women globally. At mucosal sites of the vagina, a delicate and complex balance exists between Candida spp., host immunity and local microbial communities. In fact, both immune response and microbiota composition play a central role in counteracting overgrowth of the fungus and maintaining homeostasis in the host. If this balance is perturbed, the conditions may favor C. albicans overgrowth and the yeast-to-hyphal transition, predisposing the host to VVC. To date, the factors that affect the equilibrium between Candida spp. and the host and drive the transition from C. albicans commensalism to pathogenicity are not yet fully understood. Understanding the host- and fungus-related factors that drive VVC pathogenesis is of paramount importance for the development of adequate therapeutic interventions to combat this common genital infection. This review focuses on the latest advances in the pathogenic mechanisms implicated in the onset of VVC and also discusses novel potential strategies, with a special focus on the use of probiotics and vaginal microbiota transplantation in the treatment and/or prevention of recurrent VVC.

A New Phenotype in Candida-Epithelial Cell Interaction Distinguishes Colonization- versus Vulvovaginal Candidiasis-Associated Strains

Vulvovaginal candidiasis (VVC) affects nearly 3/4 of women during their lifetime, and its symptoms seriously reduce quality of life. Although Candida albicans is a common commensal, it is unknown if VVC results from a switch from a commensal to pathogenic state, if only some strains can cause VVC, and/or if there is displacement of commensal strains with more pathogenic strains. We studied a set of VVC and colonizing C. albicans strains to identify consistent in vitro phenotypes associated with one group or the other. We find that the strains do not differ in overall genetic profile or behavior in culture media (i.e., multilocus sequence type [MLST] profile, rate of growth, and filamentation), but they show strikingly different behaviors during their interactions with vaginal epithelial cells. Epithelial infections with VVC-derived strains yielded stronger fungal proliferation and shedding of fungi and epithelial cells. Transcriptome sequencing (RNA-seq) analysis of representative epithelial cell infections with selected pathogenic or commensal isolates identified several differentially activated epithelial signaling pathways, including the integrin, ferroptosis, and type I interferon pathways; the latter has been implicated in damage protection. Strikingly, inhibition of type I interferon signaling selectively increases fungal shedding of strains in the colonizing cohort, suggesting that increased shedding correlates with lower interferon pathway activation. These data suggest that VVC strains may intrinsically have enhanced pathogenic potential via differential elicitation of epithelial responses, including the type I interferon pathway. Therefore, it may eventually be possible to evaluate pathogenic potential in vitro to refine VVC diagnosis. IMPORTANCE Despite a high incidence of VVC, we still have a poor understanding of this female-specific disease whose negative impact on women's quality of life has become a public health issue. It is not yet possible to determine by genotype or laboratory phenotype if a given Candida albicans strain is more or less likely to cause VVC. Here, we show that Candida strains causing VVC induce more fungal shedding from epithelial cells than strains from healthy women. This effect is also accompanied by increased epithelial cell detachment and differential activation of the type I interferon pathway. These distinguishing phenotypes suggest it may be possible to evaluate the VVC pathogenic potential of fungal isolates. This would permit more targeted antifungal treatments to spare commensals and could allow for displacement of pathogenic strains with nonpathogenic colonizers. We expect these new assays to provide a more targeted tool for identifying fungal virulence factors and epithelial responses that control fungal vaginitis.

Glycogen Metabolism in Candida albicans Impacts Fitness and Virulence during Vulvovaginal and Invasive Candidiasis

The polymorphic fungus Candida albicans remains a leading cause of both invasive and superficial mycoses, including vulvovaginal candidiasis (VVC). Metabolic plasticity, including carbohydrate catabolism, confers fitness advantages at anatomical site-specific host niches. C. albicans possesses the capacity to accumulate and store carbohydrates as glycogen and can consume intracellular glycogen stores when nutrients become limited. In the vaginal environment, estrogen promotes epithelial glycogen accumulation and C. albicans colonization. However, whether these factors are mechanistically linked is unexplored. Here, we characterized the glycogen metabolism pathways in C. albicans and investigated whether these impact the long-term survival of C. albicans, both in vitro and in vivo during murine VVC, or virulence during systemic infection. SC5314 and 6 clinical isolates demonstrated impaired growth when glycogen was used as the sole carbon source, suggesting that environmental glycogen acquisition is limited. The genetic deletion and complementation of key genes involved in glycogen metabolism in Saccharomyces cerevisiae confirmed that GSY1 and GLC3, as well as GPH1 and GDB1, are essential for glycogen synthesis and catabolism in C. albicans, respectively. Potential compensatory roles for a glucoamylase encoded by SGA1 were also explored. Competitive survival assays revealed that gsy1Δ/Δ, gph1Δ/Δ, and gph1Δ/Δ sga1Δ/Δ mutants exhibited long-term survival defects in vitro under starvation conditions and in vivo during vaginal colonization. A complete inability to catabolize glycogen (gph1Δ/Δ sga1Δ/Δ) also rendered C. albicans significantly less virulent during disseminated infections. This is the first study fully validating the glycogen metabolism pathways in C. albicans, and the results further suggest that intracellular glycogen catabolism positively impacts the long-term fitness of C. albicans in nutrient deficient environments and is important for full virulence. IMPORTANCE Glycogen is a highly branched polymer of glucose and is used across the tree of life as an efficient and compact form of energy storage. Whereas glycogen metabolism pathways have been studied in model yeasts, they have not been extensively explored in pathogenic fungi. Using a combination of microbiologic, molecular genetic, and biochemical approaches, we reveal orthologous functions of glycogen metabolism genes in the fungal pathogen Candida albicans. We also provide evidence that extracellular glycogen poorly supports growth across the Candida species and clinical isolates. Competitive fitness assays reveal that the loss of glycogen synthesis or catabolism significantly impacts survival during both in vitro starvation and the colonization of the mouse vagina. Moreover, a global glycogen catabolism mutant is rendered less virulent during murine invasive candidiasis. Therefore, this work demonstrates that glycogen metabolism in C. albicans contributes to survival and virulence in the mammalian host and may be a novel antifungal target.

Uncovering the Yeast Diversity in the Female Genital Tract: An Exploration of Spatial Distribution and Antifungal Resistance

Candida albicans is the leading cause of vulvovaginal yeast infections; however, other species are becoming relevant in this niche. The spatial distribution of these fungi in the female genital tract remains poorly understood. In this study, swab samples were collected from 33 patients, first from the anterior vulva and then from the upper third and right lateral wall of the vagina: 16 were with symptoms of vulvovaginal candidiasis and 17 were without characteristic symptoms; furthermore, the genus and species of each isolate were identified. In vitro susceptibility testing for fluconazole and clotrimazole was performed for all isolates. Candida albicans was the most common species (63.6%), followed by Rhodotorula spp. (51.5%), and then Candida parapsilosis (15.2%). Rhodotorula spp. and C. parapsilosis were more commonly associated with colonization, and C. albicans with infection. Rhodotorula spp. isolates presented a low susceptibility to fluconazole, with the MIC ranging from 32 to >64 µg/mL. Differences in susceptibility to fluconazole and clotrimazole between the pairs of vaginal and vulvar isolates were found for Candida albicans, Rhodotorula spp., and Nakaseomyces glabratus. The results suggest that different niches may impact the susceptibility profiles of the isolates, as well as their different clinical behaviors.

One population, multiple lifestyles: Commensalism and pathogenesis in the human mycobiome

Candida auris and Candida albicans can result in invasive fungal diseases. And yet, these species can stably and asymptomatically colonize human skin and gastrointestinal tracts. To consider these disparate microbial lifestyles, we first review factors shown to influence the underlying microbiome. Structured by the damage response framework, we then consider the molecular mechanisms deployed by C. albicans to switch between commensal and pathogenic lifestyles. Next, we explore this framework with C. auris to highlight how host physiology, immunity, and/or antibiotic receipt are associated with progression from colonization to infection. While treatment with antibiotics increases the risk that an individual will succumb to invasive candidiasis, the underlying mechanisms remain unclear. Here, we describe several hypotheses that may explain this phenomenon. We conclude by highlighting future directions integrating genomics with immunology to advance our understanding of invasive candidiasis and human fungal disease.

Acetate modulates the inhibitory effect of Lactobacillus gasseri against the pathogenic yeasts Candida albicans and Candida glabrata

The exploration of the interference prompted by commensal bacteria over fungal pathogens is an interesting alternative to develop new therapies. In this work we scrutinized how the presence of the poorly studied vaginal species Lactobacillus gasseri affects relevant pathophysiological traits of Candida albicans and Candida glabrata. L. gasseri was found to form mixed biofilms with C. albicans and C. glabrata resulting in pronounced death of the yeast cells, while bacterial viability was not affected. Reduced viability of the two yeasts was also observed upon co-cultivation with L. gasseri under planktonic conditions. Either in planktonic cultures or in biofilms, the anti-Candida effect of L. gasseri was augmented by acetate in a concentration-dependent manner. During planktonic co-cultivation the two Candida species counteracted the acidification prompted by L. gasseri thus impacting the balance between dissociated and undissociated organic acids. This feature couldn't be phenocopied in single-cultures of L. gasseri resulting in a broth enriched in acetic acid, while in the co-culture the non-toxic acetate prevailed. Altogether the results herein described advance the design of new anti-Candida therapies based on probiotics, in particular, those based on vaginal lactobacilli species, helping to reduce the significant burden that infections caused by Candida have today in human health.

Microbiome and Vulvovaginitis

Vulvovaginitis occurs in mostly reproductive aged women. Recurrent vaginitis affects overall quality of life, with a large financial burden on the patient, family, and health system. This review discusses a clinician's approach to vulvovaginitis with specific attention to the 2021 updated Center for Disease Control and Prevention guidelines. The authors discuss the role of the microbiome in vaginitis and evidence-based approaches for diagnosis and treatment of vaginitis. This review also provides updates on new considerations, diagnosis, management, and treatment of vaginitis. Desquamative inflammatory vaginitis and genitourinary syndrome of menopause are discussed as differential diagnosis of vaginitis symptoms.

Effects of n-butanol extract of Pulsatilla decoction on the NLRP3 inflammasome in macrophages infected with Candida albicans

ETHNOPHARMACOLOGICAL RELEVANCE

Pulsatilla decoction is a traditional Chinese medicine from Shang Han Lun that has been reported to have therapeutic efficacy in vulvovaginal candidiasis (VVC), and is a growth inhibitor of Candida albicans (C. albicans) in vitro, the causative agent of VVC.

AIM OF THE STUDY

In previous studies, Pulsatilla decoction has shown therapeutic benefits for VVC. With further chemical extraction of the decoction, the n-butanol extract (of Pulsatilla decoction; BEPD) was most effective against C. albicans and therapeutic for VVC. The mechanism, however, has not been elucidated. The regulation of NOD-like receptor protein 3 (NLRP3) inflammasome has recently been demonstrated as a critical component of the inflammasome complex that initiates the vaginal inflammatory response. Therefore, the effect of BEPD on NLRP3 associated with VVC was investigated.

MATERIALS AND METHODS

Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used for detecting the principal compounds of BEPD (Anemoside B4, Esculin, esculetin, Epiberberine, Berberine, Jatrorrhizine and Phellodendrine). BEPD-containing serum is prepared by intragastric administration of BEPD (4.6875 g/kg for seven days) in rats. PMA-induced THP-1 cells were challenged with C. albicans. The expression of CD68 to identify macrophages was examined by flow cytometry, the viability of THP-1 cells were assessed by CCK8 assay, the release of lactate dehydrogenase (LDH) was detected by LDH kit, and the secretion levels of IL-1β and IL-18 were evaluated through enzyme-linked immunosorbent assay (ELISA), the levels of NLRP3 were quantified by immunofluorescence, the levels of reactive oxygen species (ROS) were measured by ROS kit, and the expression of Dectin-1, Syk, TLR2, TLR4, MyD88, NF-κB, NLRP3, Caspase-1, and ASC proteins were detected by Western blot.

RESULTS

After administration of BEPD-containing serum, the levels of IL-1β, IL-18 and LDH released from macrophages were reduced in the BEPD-containing serum group compared to the model group. In addition, BEPD-containing serum inhibited the expression of ROS in macrophages, suppressed the expression of NLRP3 and inhibited the expression of TLRs/MyD88 and Dectin-1/Syk signaling pathway-related proteins.

CONCLUSIONS

BEPD suppressed the NLRP3 inflammasome and related signaling pathways in macrophages infected with C. albicans in vitro, thereby providing insight into the mechanism of BEPD action on VVC.

The effect of herbal medicine in innate immunity to Candida albicans

Candida albicans (C. albicans) is an opportunistic pathogenic fungus that often causes mucosal and systemic infections. Several pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs) and C-type lectin receptors (CLRs), have been implicated in the host recognition of C. albicans. These PRRs recognize the pathogen-associated molecular patterns (PAMPs) of C. albicans to activate innate immune cells, thereby rapidly inducing various inflammatory responses by activating intracellular signaling cascades. Herbal medicine and its active components deserve priority development due to their low toxicity and high antibacterial, antiviral and antifungal activities. This review discussed the activities of herbal compounds against C. albicans and their related mechanisms, especially their regulatory role on innate immune cells such as neutrophils, macrophages, and dendritic cells (DCs) implicated in C. albicans infections. Our work aims to find new therapeutic drugs and targets to prevent and treat diseases caused by C. albicans infection with the mechanisms by which this fungus interacts with the innate immune response.

Candidiasis profile at the outpatient department of the university of cape coast hospital in the central region of Ghana: a retrospective study

INTRODUCTION

Vulvovaginal candidiasis (VVC) is a public health problem with an estimated 138 million women globally experiencing recurrent VVC annually. The microscopic diagnosis of VVC has low sensitivity, but it remains an essential tool for diagnosis as the microbiological culture methods are limited to advanced clinical microbiology laboratories in developing countries. The study retrospectively analyzed the presence of red blood cells (RBCs), epithelial cells (ECs), pus cells (PCs) and Candida albicans positive in wet mount preparation of urine or high vaginal swabs (HVS) samples to test for their sensitivity and specificity for the diagnosis of candidiasis.

METHODS

The study is a retrospective analysis at the Outpatient Department of the University of Cape Coast between 2013 and 2020. All urine and high vagina swabs (HVS) cultures samples using Sabourauds dextrose agar with wet mount data were analyzed. 2 × 2 contingency diagnostic test was used to ascertain the diagnostic accuracy of red blood cells (RBCs), epithelial cells (ECs), pus cells (PCs), and Candida albicans positive in wet mount preparation of urine or high vaginal swabs (HVS) samples for the diagnosis of candidiasis. The association of candidiasis among patients' demographics was analyzed using relative risk (RR) analysis.

RESULTS

The high prevalence of candida infection was among female subjects 97.1% (831/856) compared to males 2.9% (25/856). The microscopic profiles which characterized candida infection were pus cells 96.4% (825/856), epithelial cells 98.7% (845/856), red blood cells (RBCs) 7.6% (65/856) and Candida albicans positive 63.2% (541/856). There was a lower risk of Candida infections among male patients compared to female patients RR (95% CI) = 0.061 (0.041-0.088). The sensitivity (95%) for detecting Candida albicans positive and red blood cells (0.62 (0.59-0.65)), Candida albicans positive and pus cells (0.75 (0.72-0.78)) and Candida albicans positive and epithelial cells (0.95 (0.92-0.96)) with corresponding specificity (95% CI) of 0.63 (0.60-0.67), 0.69 (0.66-0.72) and 0.74 (0.71-0.76) were detected among the high vaginal swab samples.

CONCLUSION

In conclusion, the study has shown that the presence of PCs, ECs, RBCs or ratio of RBCs/ECs and RBCs/PCs in the wet mount preparation from urine or HVS can enhance microscopic diagnosis of VVC cases.

Menthol-based deep eutectic systems as antimicrobial and anti-inflammatory agents for wound healing

Effective antimicrobial treatment has been identified as a serious and unmet medical need. Herein, we present a strategy based on deep eutectic systems (DES) to overcome current limitations, answering the need not only to effectively kill bacterial agents but also to avoid their adhesion and proliferation, which is associated with biofilm formation and have a crucial impact on bacterial virulence. To achieve such a goal, natural deep eutectic systems (NADES) based on menthol (Me) and saturated free fatty acids (FFA) were produced, fully physicochemical characterized, and its bioactive properties were described. The antimicrobial potential of menthol-based NADES with FFA, namely, myristic acid (MA), lauric acid (LA), and stearic acid (SA) were investigated towards a broad panel of microorganisms. The obtained data indicates that NADES possess effective antimicrobial properties towards the Gram-positive bacterial and fungal strains tested. Among the tested formulations, Me:LA at a molar ratio of 4:1 molar was used to carry out a biofilm detachment/removal assay due to is superior microbiological properties. This formulation was able to effectively lead to biofilm removal/dispersion of not only methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans, but also Escherichia coli, without the need of any additional physical force or antibiotic. Furthermore, since microbial invasion and biofilm formation is highly undesired in wound healing, namely in chronic wound healing, the wound healing properties of these eutectic formulations was also investigated. The results suggest that these NADES can cope with microbial invasion and biofilm detachment while not compromising normal keratinocyte proliferation and migration verified in wound healing and epidermis repair, while also contributing to the reduction of cell stress and inflammation via the control of ROS production. In conclusion, these results provide the indication that NADES based on Me and FFA holds great interest as antimicrobial agents for preventive and therapeutic applications in various clinical settings, including wound healing.

Impact of Lactobacillus crispatus-containing oral and vaginal probiotics on vaginal health: a randomised double-blind placebo controlled clinical trial

Health of reproductive tract is tightly associated with balance of microbial communities in this area. Bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC) represent common disturbances of vaginal communities. Vaginal discharge due to BV or VVC is a very frequent reason for visiting gynaecologist. We aimed to evaluate the impact of the novel evidence-based probiotics on BV and VVC patients. The study group included 89 BV and 93 VVC patients (aged 18-50 years) who were recruited into randomised double-blind placebo-controlled two-arm parallel trial. The patients of each diagnosis group received oral or vaginal probiotic capsules, or placebo capsules during 3 months. A probiotic capsule contained two (DSM32717 and DSM32720, in case of BV) or three (DSM32720, DSM32718 and DSM32716, in case of VVC) Lactobacillus crispatus strains. Vaginal, intestinal and general health was monitored weekly by questionnaire. Blood analyses were done in the beginning and at the end of trial. Vaginal samples were collected monthly, microscopic and molecular analyses were performed. The study revealed that both oral and vaginal capsules reduced the signs and symptoms in BV patients. Remarkable improvement was noted in Nugent score, amount and smell of discharge, but also in itching/irritation. Consumption of vaginal probiotics significantly increased the lactobacilli counts in their vagina while mean proportion of some BV-related bacteria decreased. In VVC patients, both oral and vaginal capsules lowered the combined score of two most important symptoms, amount of discharge and itching/irritation. In conclusion, the novel formulations of evidence-based well-focused probiotic L. crispatus strains are effective against BV and VVC being suitable for both vaginal and oral administration. Clinical trial registration: ISRCTN34840624, BioMed Central.

Simulated vaginal fluid: Candida resistant strains' biofilm characterization and vapor phase of essential oil effect

INTRODUCTION

Vulvovaginal candidiasis is a disease that affects millions of women worldwide. Oral formulations, topical creams or ointments are the conventional dosage forms, with an increase in drug administration through vaginal via. The use of simulated biological fluids (e.g. vaginal fluid) in the evaluation of antifungal therapies may better mimic the real biological environments and therefore provide a better understanding of the behavior of the antifungal.

METHODS

The main objective of this work was to compare planktonic growth and biofilm formation of Candida species, on common growth medium, Sabouraud Dextrose Broth (SDB) and on vaginal simulation conditions, Simulated Vaginal Fluid (SVF), through the optical density determination, colony-forming units and scanning electron microscopy. In addition, under the same conditions this study also evaluated the ability of vapor phase of oregano and white thyme essential oils (VP-EOs), potential alternative treatment, to inhibit biofilm formation and to destroy mature biofilms of vaginal isolates, through the colony-forming units determination.

RESULTS

Candida isolates maintained the same biofilm formation capacity and morphology in both media (SVF and SDB). Furthermore, the results obtained in this work related with VP-EOs effect agree with results acquired, previously, with SDB. This means that the effect of VP-EOs is not affected by the SVF medium, and that this fluid allows the dissolution of the volatile and bioactive compounds.

CONCLUSIONS

These results can predict the in vivo behavior, suggesting a potential effective application of VP-EOs as prophylactic or therapeutic treatment for biofilm-related vulvovaginal candidiasis.

α-Cyclodextrin-based poly(pseudo)rotaxane for antifungal drug delivery to the vaginal mucosa

This work aimed to evaluate poly(pseudo)rotaxanes (PPRs) potential for vaginal antifungal delivery. For this, PPRs containing terbinafine (TB) 2 % were obtained using two small surfactants, Kolliphor® RH40 and Gelucire® 48/16, and different α-cyclodextrin (α-CD) concentrations (5 and 10 %). PPRs were characterized by their physicochemical characteristics, irritation, and mucoadhesion capabilities. Formulations' performance was assessed in a vertical penetration model, which uses ex vivo entire porcine vagina. Conventional penetration experiments with excised vaginal tissue were performed as a control. Results showed all formulations were non-irritant according to the HET-CAM test. Furthermore, PPRs with 10 % αCD showed superior mucoadhesion (p < 0.05). Conventional horizontal penetration studies could not differentiate formulations (p > 0.05). However, PPRs with 10 % αCD presented a better performance in vertical ex vivo studies, achieving higher drug penetration into the vaginal mucosa (p < 0.05), which is probably related to the formulation's prolonged residence time. In addition, the antifungal activity of the formulations was maintained against Candida albicans and C. glabrata cultures. More importantly, the formulation's viscosity and drug delivery control had no negative impact on the antifungal activity. In conclusion, the best performance in a more realistic model evidenced the remarkable potential of PPRs for vaginal drug delivery.

Low intensity ultrasound-mediated drug-loaded nanoparticles intravaginal drug delivery: an effective synergistic therapy scheme for treatment of vulvovaginal candidiasis

PURPOSE

Vulvovaginal candidiasis (VVC) is a mucosal infection of the female lower genital tract for which treatment using conventional antifungal drugs shows limited effectiveness. Herein, amphotericin B-loaded poly(lactic-co-glycolic acid)-polyethylene glycol (PLGA-PEG) nanoparticles (AmB-NPs) were fabricated and combined with low intensity ultrasound (US) to mediate AmB-NPs intravaginal drug delivery to achieve productive synergistic antifungal activity in a rabbit model of VVC.

METHODS

Polymeric AmB-NPs were fabricated by a double emulsion method and the physical characteristics and biosafety of nanoparticles were analyzed. The distribution and tissue permeability of nanoparticles after intravaginal ultrasound irradiation (1.0 MHz, 1.0 W/cm², 5 min, 50% duty ratio) were observed in the vagina. The synergistic therapeutic activity of US-mediated AmB-NPs treatment was evaluated using an experimental rabbit model of VVC. Vaginal C. albicans colony counts, the pathological structure of the vagina epithelium, and Th1/Th2/Th17-type cytokine and oxidative stress levels were analyzed to investigate the therapeutic effect in vivo.

RESULTS

The prepared AmB-NPs showed an obvious shell and core structure with uniform size and good dispersion and displayed high biosafety and US-sensitive slow drug release. Ultrasound significantly enhanced nanoparticle transport through the mucus and promoted permeability in the vaginal tissue. US-mediated AmB-NPs treatment effectively increased drug sensitivity, even in the presence of the vaginal mucus barrier in vitro. On the seventh day after treatment in vivo, the combination treatment of AmB-NPs and US significantly reduced the fungal load in the vagina, achieving over 95% clearance rates, and also improved the pathological epithelium structural damage and glycogen secretion function. The expression of Th1 (IFN-γ, IL-2) and Th17 (IL-17) cytokines were significantly increased and Th2 (IL-6, IL-10) cytokines significantly decreased in the US + AmB-NP group. Furthermore, US-mediated AmB-NPs treatment effectively increased C. albicans intracellular reactive oxygen species (ROS) levels and promoted vaginal oxidation and antioxidants to normal levels.

CONCLUSION

US-mediated drug-loaded nanoparticles with intravaginal drug delivery exhibited a productive synergistic antifungal effect, which may provide a new non-invasive, safe, and effective therapy for acute or recurrent fungal vaginitis.

Oral Ibrexafungerp for Vulvovaginal Candidiasis Treatment: An Analysis of VANISH 303 and VANISH 306

Background: Ibrexafungerp is a novel antifungal treatment for acute vulvovaginal candidiasis (VVC). Using pooled data from two phase three studies (VANISH 303 and 306) in the treatment of acute VVC, this analysis sought to determine the effectiveness of ibrexafungerp in various patient subgroups that may impact outcomes. Materials and Methods: Data from VANISH 303 (NCT03734991) and VANISH 306 (NCT03987620) evaluating ibrexafungerp 300 mg twice daily (BID) for 1 day versus placebo, were pooled and analyzed to determine clinical cure rate, clinical improvement, and mycological cure at the test-of-cure visit (day 11 ± 3) and symptom resolution at the follow-up visit (day 25 ± 4) in the overall population. Patient subgroups analyzed included race, body mass index (BMI), baseline vulvovaginal signs and symptoms (VSS) score, and Candida species. Results: At the test-of-cure visit, patients receiving ibrexafungerp, compared with those who received placebo, had significantly higher rates of clinical cure (56.9% [214/376 patients] vs. 35.7% [65/182 patients]), clinical improvement (68.4% [257/376 patients] vs. 45.1% [82/182 patients]), and mycological cure (54.0% [203/376 patients] vs. 24.2% [44/182 patients]; all p < 0.0001). At the follow-up visit, patients receiving ibrexafungerp had sustained responses with higher symptom resolution rates (66.8% [251/376 patients]) versus placebo (48.4% [88/182 patients]; p < 0.0001). Race, BMI, baseline VSS score (including VSS severity score 13-18), and Candida species infection did not adversely affect clinical cure rates. Safety analysis results were consistent with the individual studies. Conclusions: Ibrexafungerp provides a safe and well-tolerated first-in-class fungicidal, 1-day oral treatment for patients with acute VVC, the first new therapy in >20 years. Clinical Trial Registration Number: NCT03734991.

The role of the genital microbiota in the acquisition and pathogenesis of sexually transmitted infections

PURPOSE OF REVIEW

There are an estimated 374 million new sexually transmitted infections (STIs) worldwide every year. Our review article examines the current evidence of how STI acquisition, transmission, and pathogenesis is impacted upon by the genital microbiota, with a focus on epidemiological, biochemical, and immunological features.

RECENT FINDINGS

At least in women, a genital microbiota dominated by lactobacilli has long been considered optimal for reproductive health, while depletion of lactobacilli may lead to a genital microenvironment dominated by anaerobic pathogens, which can manifest clinically as bacterial vaginosis. Recent research efforts have characterized genital microbiota composition in greater resolution, sometimes at species-level, using proteomics, metabolomics, and deep sequencing. This has enhanced our understanding of how specific microbiota members influence acquisition or clinical manifestation of STI pathogen infection. Other advances include a steady, though still slow, increase in the number of studies that sought to determine the genital (penile or urethral) microbiota of males and how it may impact that of their female partners' genital microbiota and risk of STI acquisition. Altogether, these data enabled us to explore the concept that genital microbiota may be sexually transmitted and influence pathogenesis and clinical presentation of other STI.

SUMMARY

With STI infection rates increasing worldwide, it is important now more than ever to find novel STI prevention strategies. Understanding if and how the genital microbiota is a modifiable risk factor for STI transmission, acquisition, and clinical manifestation may prove to be an important strategy in our efforts to curb morbidity in at risk populations.

Advanced Solid Formulations For Vulvovaginal Candidiasis

Vulvovaginal candidiasis (VVC) is an opportunistic and endogenous infection caused by a fungus of the Candida genus, which can cause pruritus, dysuria, vulvar edema, fissures and maceration of the vulva. The treatment of vaginal candidiasis is carried out mainly by antifungal agents of azole and polyene classes; however, fungal resistance cases have been often observed. For this reason, new therapeutic agents such as essential oils, probiotics and antimicrobial peptides are being investigated, which can be combined with conventional drugs. Local administration of antimicrobials has also been considered to allow greater control of drug delivery and reduce or avoid undesirable systemic adverse effects. Conventional dosage forms such as creams and ointments result in reduced residence time in the mucosa and non-sustained and variable drug delivery. Therefore, advanced solid formulations such as intravaginal rings, vaginal films, sponges and nanofibers have been purposed. In these systems, polymers in different ratios are combined aiming to achieve a specific drug release profile and high mucoadhesion. Overall, a more porous matrix structure leads to a higher rate of drug release and mucoadhesion. The advantages, limitations and technological aspects of each dosage form are discussed in detail in this review.

Vulvovaginal yeast infections, gestational diabetes and pregnancy outcome

BACKGROUND

The primary aim was to evaluate the association between gestational diabetes and blood glucose levels and vulvovaginal yeast infections in pregnancy. Secondly, we clarified the possible associations between maternal and prenatal factors, and birth outcomes and yeast infections.

METHODS

Three thousand nine hundred sixty-five pregnant women of the Kuopio Birth Cohort Study (KuBiCo) reported vulvovaginal yeast infections during pregnancy, via electronic questionnaires. Maternal and prenatal data, as well as clinical obstetric and early neonatal outcomes were registered during and after birth. The oral glucose tolerance test was performed on 3,079 women during pregnancy. Logistic regression analysis evaluated the possible multivariable associations between yeast infections, gestational diabetes and other prenatal and maternal factors.

RESULTS

No association was detected between gestational diabetes or blood glucose levels and vulvovaginal yeast infections during pregnancy. In multivariable analysis, women with yeast infections were more often multiparous, with higher education and had used more often antibiotics during pregnancy compared to others. No significant associations were detected in multivariable analysis between infections, the mode of delivery, preterm birth, birth weight or Apgar scores.

CONCLUSIONS

Women with reported vulvovaginal yeast infections managed generally well during pregnancy. They had no more gestational diabetes or higher blood glucose levels and their newborns managed equally well during early neonatal period.