Vulvovaginal candidiasis and vaginal microflora interaction: Microflora changes and probiotic therapy

Vaginal Microbiota Patterns Associated with Yeast Infection in Mexican Women, a Pilot Study

Recurrent vulvovaginal candidiasis (RVVC) is a common condition that affects women of reproductive age. The etiology of RVVC remains largely unknown, but it is believed to be associated with changes in vaginal microbiota composition. This study investigates the vaginal microbiota in 57 women with RVVC and 38 healthy controls. Bacterial DNA was analyzed using high-throughput 16S rRNA gene sequencing, and Candida and Saccharomyces species were determined by PCR. RVVC cases had a higher prevalence of Nakaseomyses glabratus (former Candida glabrata) compared to controls. Alpha diversity metrics were similar between groups, but beta diversity analysis revealed significant differences in vaginal microbiota composition. The Firmicutes abundance was altered in RVVC cases, with genus Bifidobacterium and phylum Actinobacteriota being more abundant than in the controls. At the genus level, Lactobacillus dominated controls using antibiotics, while Bifidobacterium was higher in cases with no antibiotic intake. Our study provides evidence that Nakaseomyses glabratus (former Candida glabrata) is a significant pathogen in RVVC, while Candida albicans was more prevalent in healthy women. The vaginal microbiota composition differs significantly between the two groups, with distinct patterns of bacterial abundance and changes in Firmicutes abundance.

Recent advances in therapeutic probiotics: insights from human trials

SUMMARYRecent advances in therapeutic probiotics have shown promising results across various health conditions, reflecting a growing understanding of the human microbiome's role in health and disease. However, comprehensive reviews integrating the diverse therapeutic effects of probiotics in human subjects have been limited. By analyzing randomized controlled trials (RCTs) and meta-analyses, this review provides a comprehensive overview of key developments in probiotic interventions targeting gut, liver, skin, vaginal, mental, and oral health. Emerging evidence supports the efficacy of specific probiotic strains and combinations in treating a wide range of disorders, from gastrointestinal (GI) and liver diseases to dermatological conditions, bacterial vaginosis, mental disorders, and oral diseases. We discuss the expanding understanding of microbiome-organ connections underlying probiotic mechanisms of action. While many clinical trials demonstrate significant benefits, we acknowledge areas requiring further large-scale studies to establish definitive efficacy and optimal treatment protocols. The review addresses challenges in standardizing probiotic research methodologies and emphasizes the importance of considering individual variations in microbiome composition and host genetics. Additionally, we explore emerging concepts such as the oral-gut-brain axis and future directions, including high-resolution microbiome profiling, host-microbe interaction studies, organoid models, and artificial intelligence applications in probiotic research. Overall, this review offers a comprehensive update on the current state of therapeutic probiotics across multiple domains of human health, providing insights into future directions and the potential for probiotics to revolutionize preventive and therapeutic medicine.

Genome-scale metabolic modeling reveals specific vaginal Lactobacillus strains and their metabolites as key inhibitors of Candida albicans

As the predominant constituents of the vaginal microbiome in healthy women, Lactobacillus species are considered essential in maintaining a homeostatic vaginal microbiome. Specific Lactobacillus species can produce beneficial metabolites to support their persistence within the host environment and inhibit Candida albicans colonization. Due to the extensive diversity of Lactobacillus species and their metabolites, comprehensively investigating all possible interactions remains challenging. This study employed an integrative approach combining genome-scale metabolic modeling, metagenomic sequencing, and in vitro validation to explore Lactobacillus and C. albicans interactions. Pairwise simulations of 159 Lactobacillus strains with C. albicans revealed that most strains exhibit inhibitory effects, altering fungal amino acid and carbohydrate metabolism. Key inhibitory metabolites identified included formate, L-lactate, and L-malate. Metagenomic analysis of vaginal swabs from 20 vulvovaginal candidiasis (VVC) patients and 20 healthy women showed a correlation between Lactobacillus species abundance and reduced C. albicans colonization. In vitro experiments confirmed the inhibitory effects of these metabolites and the selected Lactobacillus strains on C. albicans growth, thereby validating our computational predictions. These findings provide insights into the metabolic interactions within the vaginal microbiome and pave the way for targeted microbial or metabolite-based therapeutic strategies to manage VVC.IMPORTANCEVulvovaginal candidiasis is a prevalent fungal infection with significant implications for women's health, caused primarily by Candida albicans. Although the protective role of a Lactobacillus-dominated vaginal microbiome is well established, the metabolic mechanisms underlying the interactions between Lactobacillus species and C. albicans remain inadequately understood. Specifically, the Lactobacillus species that effectively inhibit C. albicans and the metabolic pathways involved warrant further investigation. This study offers novel insights into the metabolic mechanisms underlying Lactobacillus antagonism against C. albicans. By identifying critical metabolic pathways and inhibitory metabolites, this study enhances our understanding of vaginal microbiome dynamics and host-microbe interactions. The findings suggest that key Lactobacillus strains and their metabolites could significantly reduce harmful levels of C. albicans, paving the way for future therapeutic strategies that leverage these microbial characteristics to promote vaginal health.

In vitro co-culture model of Trichomonas vaginalis, Candida albicans, and Lactobacillus crispatus: a system for assessing antimicrobial activity and microorganism interactions in vaginitis

Trichomonas vaginalis is a flagellated protozoan causing trichomoniasis, the most common non-viral sexually transmitted infection. It is associated with various complications, particularly in asymptomatic carriers. Another major cause of vaginitis is Candida albicans, a normal member of the vaginal microbiota, which causes vulvovaginal candidiasis when immune imbalances occur, leading to recurrent infections. Treatment-resistant strains of these pathogens pose a significant challenge. Lactobacillus crispatus, a dominant species in the vaginal microbiota, produces antimicrobial compounds that help protect the vaginal mucosa. This study establishes an in vitro co-culture of T. vaginalis, C. albicans, and L. crispatus to simulate the vaginal microenvironment at the site of infection. MRS medium was chosen for the co-culture, with initial cell densities determined as follows: T. vaginalis at 1.0 × 106 trophozoites/mL (counted using a hemocytometer), 3.33 × 104 CFU/mL for C. albicans, and either 5.53 × 106 CFU/mL (for co-culture with the ATCC isolate) or 5.53 × 107 CFU/mL (for co-culture with a fresh clinical isolate) for L. crispatus. The cell densities of C. albicans and L. crispatus were quantified as colony-forming units (CFU) on selective agar. The incubation period for co-culture, ensuring optimal growth of all microorganisms, was 24 hours. In co-culture, L. crispatus at both tested densities acidified the medium. The co-culture system demonstrated lower MIC values for metronidazole (50 µM in the ATCC isolate co-culture and 25 µM with the fresh clinical isolate) and lower MFC values for fluconazole (6.25 µM), compared to monocultures of T. vaginalis (100 µM) and C. albicans (12.50 µM). Furthermore, the triple co-culture increased the cytotoxicity to vaginal cell and erythrocytes for the ATCC isolate while significantly inhibited both biofilm formation and metabolic activity of C. albicans (by up to 92% and 90%, respectively), as well as its yeast-to-hyphae transition (by up to 70%). SEM analyses highlighted the morphological differences among T. vaginalis, C. albicans, and L. crispatus, including isolate-specific size variations in the protozoan. These findings suggest that this in vitro co-culture system is a valuable tool for evaluating the antimicrobial efficacy of novel compounds against vaginitis pathogens and for studying interactions within the vaginal microenvironment.

Double-Layer Magnetic Microspheres with Dual Drug Delivery of Antibacterial and Maintenance Agents for the Treatment of Candida albicans Vaginitis

Candida vaginitis (CV) is the most common fungal infection among gynecological diseases, caused by Candida albicans (C. albicans). Traditional treatment for CV has led to increased antibiotic resistance, complicating treatment and indiscriminately killing both pathogens and beneficial bacteria in the vagina. Additionally, the inconvenience of traditional vaginal administration and the short residence time of treatments pose significant challenges. We developed a safe and effective combination drug delivery platform featuring magnetic bilayer gel microspheres to combine antibacterial properties and maintain the balance of the microbial community. This platform was characterized through a series of in vitro tests evaluating its dissolution, adherence, and retention properties, graded slow release, and antimicrobial effects. In vivo studies using CV mice models were conducted to assess antifungal properties, microecological regulation, magnetic residency, safety, and other related aspects. The results demonstrated that the material effectively inhibits the growth of C. albicans. It also increases the drug's residence time in the body and successfully releases probiotics, thereby improving vaginal microecology and promoting the recovery of inflammation to normal levels. These findings suggest a novel therapeutic approach for managing C. albicans vaginitis.

Expert Opinion on the Use of Probiotics in General Gynecological Conditions

Various gynecological conditions, including bacterial vaginosis, urinary tract infection, genitourinary syndrome of menopause, polycystic ovarian syndrome, and vulvovaginal candidiasis, impose a significant global burden, including among the Indian population. This expert opinion emphasizes the importance of oral probiotic supplementation in managing these conditions. A physical meeting with 14 experts was conducted on June 29-30, 2024, during which they highlighted that probiotics, particularly Lactobacillus species, have beneficial effects on restoring and maintaining healthy vaginal microbiota. Probiotics also promote vaginal health and aid in treating conditions such as bacterial vaginosis, vulvovaginal candidiasis, polycystic ovarian syndrome, and genitourinary syndrome of menopause. Probiotics are proven effective in managing bacterial vaginosis by enhancing beneficial bacteria and reducing harmful ones. They help prevent and treat recurrent urinary tract infections by increasing lactobacilli levels, inhibiting Candida growth, and maintaining vaginal pH to prevent vulvovaginal candidiasis. Symptoms of genitourinary syndrome of menopause, such as vaginal dryness, itching, and recurrent urinary tract infections, can be alleviated through a combination of Lactobacillus-based probiotics and estrogen therapy. Experts also recommended probiotic supplementation for women with polycystic ovarian syndrome to improve both chemical and clinical pregnancy rates. Probiotics help modulate gut microbiota; improve blood glucose levels, insulin resistance, cholesterol, and androgen levels; restore the LH/FSH ratio; and enhance reproductive health. This expert opinion underscores the key role of Lactobacillus species in treating and preventing various gynecological disorders such as bacterial vaginosis, vulvovaginal candidiasis, genitourinary syndrome of menopause, urinary tract infection, and polycystic ovarian syndrome by restoring and maintaining vaginal microbiota, thus supporting overall feminine health.

Efficacy and safety of vaginal suppositories containing combination of Natamycin and Lactulose in treatment of vulvovaginal candidiasis: international, randomized, controlled, superiority clinical trial (combination of Natamycin and Lactulose for treatment of vulvovaginal candidiasis)

BACKGROUND

The study aimed to assess the efficacy and safety of Natamycin + Lactulose vaginal suppositories (100 mg natamycin and 300 mg lactulose) (AVVA RUS JSC, Russia) in adult females with vulvovaginal candidiasis.

METHODS AND RESULTS

An international, randomized, controlled, assessor-blinded clinical trial enrolled 218 females randomly distributed into three groups: Natamycin + Lactulose (92 patients), Lactulose (36 patients), and Pimafucin® (90 patients). The study drug and comparator drugs had an identical dosing regimen (one suppository intravaginally once a day at bedtime for six days). The study involved four visits to the study site with examination at Visits 2 and 3. The fixed-dose combination of Natamycin + Lactulose was superior to both comparator drugs in terms of the primary efficacy endpoint defined as the percentage of patients achieving a clinical recovery: the absence of symptoms of vulvovaginal candidiasis. At Visit 2, clinical recovery was reported in 81.6% of females in the Natamycin + Lactulose group compared to 42.9% and 62.3% of patients in the Lactulose and Pimafucin groups, respectively. The difference in proportions was 38.8% and 18.4%. In the Natamycin + Lactulose group, microscopic recovery was observed in 75.9% of patients at Visit 2 and in 90.8% of patients at Visit 3. In the Lactulose group, 45.7% and 74.3% subjects responded positively at Visits 2 and 3. In Pimafucin group, microscopic recovery was reported in 71.3% and 88.5% of patients at Visits 2 and 3, respectively, while no differences were observed between the Natamycin + Lactulose and Pimafucin groups at both visits. At Visit 3, the number of vaginal lactobacilli was significantly higher in the Natamycin + Lactulose group. In females with the low baseline content of vaginal lactobacilli, the combination drug under investigation increased the vaginal lactobacilli content to the reference values in 15.4% and 20.9% of patients at Visit 2 and Visit 3, respectively.

CONCLUSIONS

The fixed-dose combination Natamycin + Lactulose 100 mg + 300 mg vaginal suppositories (AVVA RUS JSC, Russia) demonstrated superior efficacy compared to 1) Pimafucin 100 mg and 2) Lactulose 300 mg vaginal suppositories in adult females with vulvovaginal candidiasis.

TRIAL REGISTRATION

NCT06411314, retrospectively registered on May, the 13th, 2024.

Comparative efficacy of topical commercial Chinese polyherbal preparation for vulvovaginal candidiasis: a network meta-analysis

Objective

To systematically evaluate the differences in the efficacy of commonly used topical commercial Chinese polyherbal preparations (CCPPs) for vulvovaginal candidiasis (VVC), and to provide evidence-based reference for clinical drug regimens.

Methods

Computer searched major Chinese and English literature databases, and collected randomized controlled trials (RCTs) of external use of CCPPs combined with conventional treatment (CT, test group) versus CT alone (control group) in patients with VVC. After screening the literature, the quality of the included studies was assessed using the risk of bias assessment tool recommended in 5.3 of the Cochrane Handbook. Outcome data for each outcome measure were extracted and a network meta-analysis was performed using Stata 15.0.

Results

A total of 74 RCTs with a total of 8,151 patients were included, nine interventions were involved. The results of network meta-analysis showed that, Fufang Shajiziyou suppository combined with CT was more effective in improving the negative conversion rate and controlling the recurrence rate of Candida albicans. Kangfu gel combined with CT had the better effect in relieving pruritus. Baofukang suppository combined with CT was the most effective in reducing leukorrhea. Fufukang spray combined with CT had fewer adverse reactions.

Conclusion

The addition of CCPPs to CT may acquire a better curative effect in patients with VVC and external does not significantly increase the occurrence of adverse reactions. However, due to the low quality of the included literature, larger-scale, higher-quality clinical studies are still needed.

Systematic Review Registration

PROSPERO, NO: CRD42023410244.

Exploring the Potential Use of Probiotics, Prebiotics, Synbiotics, and Postbiotics as Adjuvants for Modulating the Vaginal Microbiome: a Bibliometric Review

Women's health is related to several factors that include physical, mental, and reproductive health. Additionally, the vaginal microbiota modulation performs a fundamental role in the regulation of physiological homeostasis and dysbiosis, which provides us a potential overview of the use of different biotic agents and their implications for female health. The objective of this work was propitiated insights and conception about the influence of probiotics, prebiotics, synbiotics, and postbiotics as adjuvants for prevention/treatment on the main infections that can affect women's health. Therefore, seventy-one studies published in the Web of Science Core Collection database from 1999 to 2024 were evaluated and performed to a bibliometric analysis employing the VOSviewer software for scientific mapping and network analysis. Our results suggest that administration of biotic agents as adjuvants are relevant for the prevention and/or treatment of the main diseases that affect female health, since they contribute to a healthy vaginal microbiota through anti-inflammatory and antimicrobial activities. Most clinical studies have demonstrated the effectiveness of intervention using probiotics to the detriment of other biotic agents in women's health, being bacterial vaginosis, polycystic ovary syndrome, and vulvovaginal candidiasis, the main diseases evaluated. However, preclinical studies have emphasized that the inhibition of pathogens responsible for the process of vaginal dysbiosis may be due to the formation of biofilm and the synthesis of compounds that could prevent the adhesion of these microorganisms. Future perspectives point to the beneficial modulation of the vaginal microbiota by biotic agents as a promising adjuvant approach to improve women's health.

Vaginal Candida albicans infections: host-pathogen-microbiome interactions

Candida albicans is a fungus that colonizes the gut, oral, and vaginal mucosae of most humans without causing disease. However, under certain predisposing conditions this fungus can cause disease. Candida albicans has several factors and attributes that facilitate its commensal and pathogenic lifestyles including the transition from a yeast to a hyphal morphology, which is accompanied by the expression of virulence factors. These factors are central in candidiasis that can range from invasive to superficial. This review focuses on one example of a superficial disease, i.e. vulvovaginal candidiasis (VVC) that affects ~75% of women at least once with some experiencing four or more symptomatic infections per year (RVVC). During VVC, fungal factors trigger inflammation, which is maintained by a dysregulated innate immune response. This in turn leads to immunopathology and symptoms. Another unique characteristic of the vaginal niche, is its Lactobacillus-dominated microbiota with low species diversity that is believed to antagonize C. albicans pathogenicity. The importance of the interactions between C. albicans, the host, and vaginal microbiota during commensalism and (R)VVC is discussed in this review, which also addresses the application of this knowledge to identify novel treatment strategies and to study vaginal C. albicans infections.

Genetic association between human skin microbiota with vaginitis: a two-sample Mendelian randomization study

The human skin microbiome is closely associated with various diseases. We aimed to find the causal association of the human skin microbiome with vaginitis. A two-way two-sample Mendelian randomization study used summary statistics of the human skin microbiota from the largest genome-wide association study meta-analysis. Pooled statistics for vaginitis disease were obtained from the FinnGen consortium R10 release. Inverse variance weighted, MR-Egger, weighted median, weighted model, MR-PRESSO, and STEIGER methods were used to test for causal associations between different parts of the human skin microbiota and vaginitis disease in either dry or moist environments. IVW estimates suggest that phylococcus hominischaracterizes a protective effect against vaginitis lesions at the Antecubitalfossa wet site. Staphylococcus in the dry state at the Dorsalforearm site also demonstrated a protective effect against vaginitis lesions. Micrococcus showed a trend of up-regulation of vaginitis risk under IVW method estimation. In contrast, Anaerococcus and Veillonella were associated with a low risk of vaginitis as estimated by the IVW method: ASV061 and ASV065. In the Class, IVW estimation showed that Bacilli at Antecubitalfossa site had an increased risk effect on vaginitis in the moist skin condition. Similarly in Genus, Staphylococcus at Antecubitalfossa sites had an increased risk effect against vaginitis in the moist skin condition. Based on the results of the inverse MR analysis, no significant causal effect of vaginitis on the human skin microbiota was found. This two-sample bidirectional Mendelian randomization study found a causal relationship between seven human skin microbiota and vaginitis, further enriching our understanding of the value of skin flora in reproductive diseases such as vaginitis.

Vaginal prevention of Candida albicans: synergistic effect of lactobacilli and mannan oligosaccharides (MOS)

Vulvovaginal candidiasis (VVC) affects approximately 30-50% of women at least once during their lifetime, causing uncomfortable symptoms and limitations in their daily quality of life. Antifungal therapy is not very effective, does not prevent recurrencies and usually causes side effects. Therefore, alternative therapies are urgently needed. The goal of this work was to investigate the potential benefits of using mannan oligosaccharides (MOS) extracts together with a Lactobacillus sp. pool, composed by the most significant species present in the vaginal environment, to prevent infections by Candida albicans. Microbial growth of isolated strains of the main vaginal lactobacilli and Candida strains was assessed in the presence of MOS, to screen their impact upon growth. A pool of the lactobacilli was then tested against C. albicans in competition and prophylaxis studies; bacterial and yeast cell numbers were quantified in specific time points, and the above-mentioned studies were assessed in simulated vaginal fluid (SVF). Finally, adhesion to vaginal epithelial cells (HeLa) was also evaluated, once again resorting to simultaneous exposure (competition) or prophylaxis assays, aiming to measure the effect of MOS presence in pathogen adherence. Results demonstrated that MOS extracts have potential to prevent vaginal candidiasis in synergy with vaginal lactobacilli, with improved results than those obtained when using lactobacilli alone. KEY POINTS: Potential benefits of MOS extracts with vaginal lactobacilli to prevent C. albicans infections. MOS impacts on growth of vaginal lactobacilli pool and C. albicans in SVF. MOS extracts in synergy with L. crispatus inhibit C. albicans adhesion in HeLa cells.

The oral-gut microbiome axis in breast cancer: from basic research to therapeutic applications

As a complicated and heterogeneous condition, breast cancer (BC) has posed a tremendous public health challenge across the world. Recent studies have uncovered the crucial effect of human microbiota on various perspectives of health and disease, which include cancer. The oral-gut microbiome axis, particularly, have been implicated in the occurrence and development of colorectal cancer through their intricate interactions with host immune system and modulation of systemic inflammation. However, the research concerning the impact of oral-gut microbiome axis on BC remains scarce. This study focused on comprehensively reviewing and summarizing the latest ideas about the potential bidirectional relation of the gut with oral microbiota in BC, emphasizing their potential impact on tumorigenesis, treatment response, and overall patient outcomes. This review can reveal the prospect of tumor microecology and propose a novel viewpoint that the oral-gut microbiome axis can be a breakthrough point in future BC studies.

Vaginal micro-environment disorder promotes malignant prognosis of low-grade cervical intraepithelial neoplasia: a prospective community cohort study in Shanxi Province, China

PURPOSE

Emerging evidence suggests that vaginal micro-environment disorder is closely related to the development of cervical lesions. Low-grade cervical intraepithelial neoplasia (CIN1), as an early stage of cervical lesions, exhibits a high risk of progressing to high-grade lesions or even cervical cancer. However, the effect of vaginal micro-environment on the malignant prognosis of CIN1 remains uncertain.

METHODS

A total of 504 patients diagnosed with CIN1 by pathology, who were from the population-based cohorts established in Shanxi Province, China, were enrolled and followed up for 2 years. Micro-environmental factors such as vaginal pH, cleanliness, hydrogen peroxide (H2O2), β-glucuronidase (GUSB), leucocyte esterase (LE), and sialidase (SNA) were detected to evaluate their effect on the malignant prognosis of CIN1.

RESULTS

Abnormal vaginal pH (HR = 1.472, 95%CI 1.071-2.022), cleanliness (HR = 1.446, 95%CI 1.067-1.960), H2O2 (HR = 1.525, 95%CI 1.155-2.013), GUSB (HR = 1.739, 95%CI 1.235-2.448), LE (HR = 1.434, 95%CI 1.038-1.981), and SNA (HR = 1.411, 95%CI 1.065-1.870) could promote a higher incidence of CIN1 malignant prognosis, and the combined effects of these micro-environmental factors resulted in a nearly twofold increased risk (HR = 2.492, 95%CI 1.773-3.504) compared to any single factor alone, especially under the high-risk human papillomavirus (HR-HPV) infection. Notably, the cumulative incidence of malignant prognosis for CIN1 gradually increased during the early follow-up period, reaching its peak at approximately 8 months, and then stabilizing.

CONCLUSION

Vaginal micro-environment disorder could promote CIN1 malignant prognosis, particularly in HR-HPV-infected women. Taking micro-environmental factors as the breakthrough, our study provides a feasible vision for preventing early stage cervical lesions.

Efficacy of Limosilactobacillus fermentum in the management of vulvovaginal candidiasis: comparative analysis with topical miconazole in a single-blind randomized clinical trial

Introduction

Vulvovaginal candidiasis (VVC) significantly impacts women's quality of life and often shows a high recurrence rate despite conventional antifungal therapies. This study evaluates the efficacy of Limosilactobacillus fermentum (LF5), a probiotic, as an alternative treatment option to conventional miconazole therapy in managing VVC.

Methods

The randomized, single-blind clinical trial involved 100 premenopausal women diagnosed with VVC. Participants were assigned to either a vaginal capsule containing LF5 probiotic strain or miconazole. Treatments were administered once daily for three consecutive days. Microbiological eradication of Candida spp. and recurrence rates were assessed at 30 days post-treatment. The trial was registered with the Italian Ministry of Health.

Results

Both treatments achieved a high rate of microbiological eradication of Candida spp. within the three-day treatment period (96% for LF5 and 94% for miconazole). Recurrence rates within 2 weeks post-treatment were low and similar between the groups (10% for LF5 and 17% for miconazole). LF5 was found to have a significantly lower incidence of local adverse reactions compared to miconazole (4 vs. 12%).

Discussion

LF5 presents a viable alternative to miconazole for the treatment of VVC, offering comparable efficacy with fewer side effects. The results suggest that probiotic treatments can potentially enhance patient compliance and quality of life by reducing adverse reactions and recurrence rates. Further research is needed to confirm these findings in larger and more diverse populations.

Enhancing Therapeutic Efficacy of Cinnamon Essential Oil by Nanoemulsification for Intravaginal Treatment of Candida Vaginitis

Background

Due to its prevalence, recurrence, and the emergence of drug-resistance, Candida vaginitis significantly impacts the well-being of women. Although cinnamon essential oil (CEO) possesses antifungal activity, its hydrophobic properties limit its clinical application.

Purpose

To overcome this challenge, a nanoemulsification technology was employed to prepare cinnamon essential oil-nanoemulsion (CEO@NE), and its therapeutic efficacy and action mechanism for Candida vaginitis was investigated in vivo and in vitro.

Materials and Methods

CEO@NE, composed of 4% CEO, 78% distilled water, and 18% Tween 80, was prepared by ultrasonic nanoemulsification. The physical properties, anti-Candida activity, cytotoxicity, immunomodulatory potential and storage stability of CEO@NE were explored. Subsequently, the effect of intravaginal CEO@NE treatment on Candida vaginitis was investigated in mice. To comprehend the possible mechanism of CEO@NE, an analysis was conducted to ascertain the production of intracellular reactive oxygen species (ROS) in C. albicans.

Results

CEO@NE, with the droplet size less than 100 nm and robust storage stability for up to 8 weeks, exhibited comparable anti-Candida activity with CEO. CEO@NE at the concentration lower than 400 μg/mL had no cytotoxic and immunomodulatory effects on murine splenocytes. Intravaginal treatment of CEO@NE (400 μg/mL, 20 μL/day/mouse for 5 consecutive days) curbed Candida colonization, ameliorated histopathological changes, and suppressed inflammatory cytokine production in mice intravaginally challenged with C. albicans. Notably, this treatment preserved the density of vaginal lactic acid bacteria (LAB) crucial for vaginal health. Co-culturing C. albicans with CEO@NE revealed concentration-dependent augmentation of intracellular ROS generation and ensuing cell death. In addition, co-culturing LPS-stimulated murine splenocytes with CEO@NE yielded a decrease in the generation of cytokines.

Conclusion

This discovery provides insight into the conceivable antifungal and anti-inflammatory mechanisms of CEO@NE to tackle Candida vaginitis. CEO@NE offers a promising avenue to address the limitations of current treatments, providing novel strategy for treating Candida vaginitis.

Microorganism-derived extracellular vesicles: emerging contributors to female reproductive health

Extracellular vesicles (EVs) are cell-derived nanoparticles that carry small molecules, nucleic acids, and proteins long distances in the body facilitating cell-cell communication. Microorganism-derived EVs mediate communication between parent cells and host cells, with recent evidence supporting their role in biofilm formation, horizontal gene transfer, and suppression of the host immune system. As lipid-bound bacterial byproducts, EVs demonstrate improved cellular uptake and distribution in vivo compared to cell-free nucleic acids, proteins, or small molecules, allowing these biological nanoparticles to recapitulate the effects of parent cells and contribute to a range of human health outcomes. Here, we focus on how EVs derived from vaginal microorganisms contribute to gynecologic and obstetric outcomes. As the composition of the vaginal microbiome significantly impacts women's health, we discuss bacterial EVs from both healthy and dysbiotic vaginal microbiota. We also examine recent work done to evaluate the role of EVs from common vaginal bacterial, fungal, and parasitic pathogens in pathogenesis of female reproductive tract disease. We highlight evidence for the role of EVs in women's health, gaps in current knowledge, and opportunities for future work. Finally, we discuss how leveraging the innate interactions between microorganisms and mammalian cells may establish EVs as a novel therapeutic modality for gynecologic and obstetric indications.

Enhanced Solubility and Bioavailability of Clotrimazole in Aqueous Solutions with Hydrophobized Hyperbranched Polyglycidol for Improved Antifungal Activity

The poor solubility of clotrimazole in the aqueous medium and the uncontrolled removal of the drug-loaded suppository content limit its effectiveness in the treatment of vulvovaginal candidiasis. We present here the aqueous formulations of clotrimazole in the form of non-Newtonian structured fluids, i.e., Bingham plastic or pseudoplastic fluids constructed of hyperbranched polyglycidol, HbPGL, with a hydrophobized core with aryl groups such as phenyl or biphenyl. The amphiphilic constructs were obtained by the modification of linear units containing monohydroxyl groups with benzoyl chloride, phenyl isocyanate, and biphenyl isocyanate, while the terminal 1,2-diol groups in the shell were protected during the modification step, followed by their deprotection. The encapsulation of clotrimazole within internally hydrophobized HbPGLs using a solvent evaporation method followed by water addition resulted in structured fluids formation. Detailed Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses performed for aryl-HbPGLs with clotrimazole revealed the difference in drug compatibility among polymers. Clotrimazole in biphenyl-enriched HbPGL, unlike phenyl derivatives, was molecularly distributed in both the dry and the hydrated states, resulting in transparent formulations. The shear-thinning properties of the obtained fluid formulations make them injectable and thus suitable for the intravaginal application. Permeability tests performed with the usage of the Franz diffusion cell showed a 5-fold increase in the permeability constant of clotrimazole compared to drugs loaded in a commercially available disposable tablet and a 50-fold increase of permeability in comparison to the aqueous suspension of clotrimazole. Furthermore, the biphenyl-modified HbPGL-based drug liquid showed enhanced antifungal activity against both Candida albicans and Candida glabrata that was retained for up to 7 days, in contrast to the phenyl-HbPGL derivatives and the tablet. With their simple formulation, convenient clotrimazole/biphenyl-HbPGL formulation strategy, rheological properties, and enhanced antifungal properties, these systems are potential antifungal therapeutics for gynecological applications. This study points in the synthetic direction of improving the solubility of poorly water-soluble aryl-enriched pharmaceuticals.

Mechanisms of probiotic modulation of ovarian sex hormone production and metabolism: a review

Sex hormones play a pivotal role in the growth and development of the skeletal, neurological, and reproductive systems. In women, the dysregulation of sex hormones can result in various health complications such as acne, hirsutism, and irregular menstruation. One of the most prevalent diseases associated with excess androgens is polycystic ovary syndrome with a hyperandrogenic phenotype. Probiotics have shown the potential to enhance the secretion of ovarian sex hormones. However, the underlying mechanism of action remains unclear. Furthermore, comprehensive reviews detailing how probiotics modulate ovarian sex hormones are scarce. This review seeks to shed light on the potential mechanisms through which probiotics influence the production of ovarian sex hormones. The role of probiotics across various biological axes, including the gut-ovarian, gut-brain-ovarian, gut-liver-ovarian, gut-pancreas-ovarian, and gut-fat-ovarian axes, with a focus on the direct impact of probiotics on the ovaries via the gut and their effects on brain gonadotropins is discussed. It is also proposed herein that probiotics can significantly influence the onset, progression, and complications of ovarian sex hormone abnormalities. In addition, this review provides a theoretical basis for the therapeutic application of probiotics in managing sex hormone-related health conditions.

Enhancing Immunity and Modulating Vaginal Microflora Against Candidal Vaginitis Through Nanoemulsion Supplemented with Porphyra Oligosaccharide as an Intravaginal Vaccine Adjuvant

Background

Intravaginal vaccination is an encouraging approach to prevent infectious vaginitis, with nanoemulsions showing effectiveness as mucosal adjuvants.

Purpose

This study aimed to formulate a nanoemulsion incorporating Porphyra oligosaccharide (PO@NE) and assess its effectiveness as a mucosal adjuvant in intravaginal vaccines against candidal vaginitis.

Materials and Methods

PO@NE was prepared, and the stability, immunomodulatory activity and cytotoxicity were screened in vitro. Further, the preventive effect of PO@NE as adjuvants for heat-killed Candida albicans (HK-CA) vaccines was explored in a murine model of candidal vaginitis, in comparison with those supplemented with polysaccharide (PP@NE). The mice were intravaginally vaccinated with 106 HK-CA cells, suspended in 1% NE without or with either PO or PP at a final concentration of 6.5 μg/mL, in a total volume of 20 μL. This vaccination was intravaginally administered once a week for 3 weeks. One week following the final vaccination, the mice underwent an intravaginal challenge with 107 C. albicans cells. One week after the challenge, the mice were euthanized to isolate serum, spleen, vaginal washes, and vaginal tissues for analysis.

Results

PP@NE and PO@NE, with diameters approximately around 100 nm, exhibited exceptional stability at 4°C and low cytotoxicity when used at a concentration of 1% (v/v). Intravaginal vaccination with HK-CA adjuvanted with PO@NE effectively protected against candidal vaginitis evidenced by less Candida hyphae colonization, milder mucosal damage and cell infiltration. Moreover, enhanced mucosal antibody production, induction of T helper (Th)1 and Th17-related immune responses, enlarged the population of CD8+ cells, and elevated vaginal microflora diversity were observed in vaccinated mice. Interestingly, the potency was rather attenuated when PO@NE was replaced with PP@NE.

Conclusion

These findings indicate PO@NE as a HK-CA vaccine adjuvant for candidal vaginitis prevention via enhancement of both cellular and humoral immunity and modulation of vaginal microflora, emphasizing further intravaginal vaccination development.

Preparation and evaluation of Cordyceps militaris polysaccharide- and sesame oil-loaded nanoemulsion for the treatment of candidal vaginitis in mice

BACKGROUND

Candida albicans is the most prevalent fungal pathogen, affecting over 75% of women who have experienced candidal vaginitis. Given the identification of drug-resistant C. albicans strains, there is an urgent need to develop therapeutic methods for treating vaginal Candida infection. Polysaccharide is the major bioactive component of Cordyceps militaris, known to modulate immune responses and alleviate inflammation. Sesame oil is known with anti-microbial and anti-inflammatory activities.

METHODS

C. militaris polysaccharide was prepared and formulated with sesame oil to prepare emulsion and nanoemulsion, which are ideal mucosal delivery systems for both hydrophobic and hydrophilic compounds concurrently. The physical property and storage stability of these formulations were illustrated, and their effects on ameliorating vaginitis were investigated in a murine model of vaginal Candida infection.

RESULTS

C. militaris polysaccharide-containing nanoemulsion showed smaller particle size, lower polydispersity index, higher zeta-potential and better stability than emulsion. Intravaginal administration of C. militaris polysaccharide-containing nanoemulsion significantly attenuated C. militaris colonization and vaginitis. Notably, these formulations exerted distinct effects on modulating cell infiltration and splenic cytokine production. Moreover, different profile of vaginal microflora was observed among the treatment groups, revealing the potential action mechanisms of these formulations to mitigate vaginal Candida infection.

CONCLUSION

C. militaris polysaccharide- and sesame oil-containing nanoemulsion is potential to be developed as intravaginal therapeutic strategy for C. albicans-induced vaginitis.

Anti-Candida and Anti-Inflammatory Properties of a Vaginal Gel Formulation: Novel Data Concerning Vaginal Infection and Dysbiosis

Vaginal ecosystem is a unique environment where, in physiological conditions, lactobacilli dominate. However, pathogenic microbial species responsible for vaginitis and vaginosis can also harbor vaginal microbiota. To extend our previously published data, we analyzed here both the anti-Candida and anti-inflammatory properties of the vaginal gel formulation, Respecta^® Balance Gel (RBG), commercialized as an adjuvant to treat vaginitis and vaginosis. We evaluated its activity by an in vitro model where a monolayer of A-431 vaginal epithelial cells was infected by Candida albicans in the presence of RBG or the placebo formulation (pRBG). Specifically, we tested the RBG capacity to counteract C. albicans virulence factors and their anti-inflammatory properties. Our results show that, unlike the placebo, RBG reduces C. albicans adhesion, its capacity to form hyphae and C. albicans-induced vaginal cell damage. Interestingly, both RBG and pRBG reduce LPS-induced IL-8 secretion (with RBG being the most effective), demonstrating that also the placebo retains anti-inflammatory properties. From our experimental approach, we highlighted the possible role of farnesol on such effects, but we would like to point out that lactic acid, polydextrose and glycogen too must be relevant in the actual application. In summary, our results show that RBG impairs C. albicans virulence and is able to reduce the inflammation in the vaginal environment, ultimately allowing the establishment of a balanced vaginal ecosystem.

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.

Use of probiotic lactobacilli in the treatment of vaginal infections: In vitro and in vivo investigations

The vaginal microbiome is a distinct component of the human microbiome that is colonized by a wide variety of microorganisms. Lactobacilli are the most frequently identified microorganisms in the healthy human vagina. These Gram-positive bacilli can acidify the vaginal microenvironment, inhibit the proliferation of other pathogenic microorganisms, and promote the maintenance of a eubiotic vaginal microbiome. However, a vaginal flora with a reduced proportion or abundance of lactobacilli is associated with various vaginal infections that have been linked to serious health consequences such as infertility, preterm birth, pelvic inflammatory disease, premature rupture of membranes, and miscarriage. Due to their “Generally Recognized as Safe” classification and critical role in vaginal health, probiotic lactobacilli have been widely used as an alternative or adjunct to traditional antibiotic therapy for the treatment of vaginal infections and restoration of the vaginal microbiome. This review focuses on the significant role of probiotic lactobacilli in the vaginal microenvironment and discusses the use of probiotic lactobacilli in the treatment of female vaginal infections in vitro and in vivo.