Inhibitory effect of Lactobacillus gasseri CCFM1201 on Gardnerella vaginalis in mice with bacterial vaginosis

Methanol Extract of Pueraria lobata (Willd.) Root and Its Active Ingredient, Puerarin, Induce Apoptosis in HeLa Cells and Attenuates Bacterial Vaginosis in Gardnerella vaginalis-Infected Mice

Pueraria lobata (Willd.) has been used as food since ancient times, and its roots have been used mainly as a traditional herbal medicine to treat various diseases in East Asia. Puerarin is one of the major active ingredients in the roots of P. lobata. The purpose of this study was to examine the effects of the methanol extract of P. lobata roots (PRME) and puerarin on apoptosis in cervical cancer and inflammation-relieving effects in vaginitis. First, we prepared the PRME and confirmed the puerarin content of PRME through HPLC analysis. We performed a TUNEL assay, Hoechst 33342 staining, and western blotting using HeLa cells, a human cervical cancer cell line. Both the PRME and puerarin exhibited antiproliferative effects in HeLa cells by inducing apoptosis through the activation of the extrinsic death receptor and intrinsic mitochondrial pathways, thereby demonstrating their anticancer efficacy against human cervical cancer. Next, a mouse model of vaginitis induced by Gardnerella vaginalis (GV) infection was established by inoculating C57BL/6 mice with β-estradiol-3-benzoate and GV (1 × 108 CFU). Histological analysis and PCR confirmed that the administration of PRME or puerarin to GV-infected mice alleviated reproductive tract vaginitis symptoms. Additionally, we confirmed that PRME or puerarin treatment decreased myeloperoxidase activity and reduced inflammation by regulating cytokines through the secretion of inflammatory mediators in mouse vaginal tissue. These results demonstrate that PRME and puerarin can be used as potential adjuvants or therapeutic agents with anticancer and anti-inflammatory properties to inhibit the progression of human cervical cancer and alleviate vaginitis.

Vaginal colonization of Lactobacilli: Mechanism and function

Traditional antibiotics exhibit numerous limitations in addressing female reproductive tract infections associated with vaginal microbiota disturbances. In recent years, the application of vaginal probiotics, notably lactobacilli, has demonstrated significant therapeutic benefits. In this article, we summarize the adhesion and colonization mechanisms of female vaginal lactobacilli, influencing factors, functions, and the current status of lactobacillus applications. Meanwhile, in this review, the diverse antagonistic pathogens of vaginal lactobacilli and their characteristics of adhesion and colonization on the vaginal mucosal surface were enumerated and examined. Some probiotic strains with potential clinical relevance that have been identified were also summarized, aiming to offer novel insights for the development of probiotic formulations and the treatment of female reproductive tract infections.

Antibiofilm Agents for the Treatment and Prevention of Bacterial Vaginosis: A Systematic Narrative Review

BACKGROUND

Bacterial vaginosis (BV) is difficult to eradicate due to BV biofilms protecting BV bacteria (Gardnerella, Prevotella, and other genera). With the growing understanding of biofilms, we systematically reviewed the current knowledge on the efficacy of anti-BV biofilm agents.

METHODS

We searched literature in the Scopus, Medline, and Embase databases for empirical studies investigating substances for the treatment of BV biofilms or prevention of their recurrence and their efficacy and/or safety.

RESULTS

Of 201 unique titles, 35 satisfied the inclusion criteria. Most studies (89%) reported on preclinical laboratory research on the efficacy of experimental antibiofilm agents (80%) rather than their safety. Over 50% were published within the past 5 years. Agents were classified into 7 groups: antibiotics, antiseptics, cationic peptides, enzymes, plant extracts, probiotics, and surfactants/surfactant components. Enzymes and probiotics were most commonly investigated. Earlier reports of antibiotics having anti-BV biofilm activity have not been confirmed. Some compounds from other classes demonstrated promising anti-BV biofilm efficacy in early studies.

CONCLUSIONS

Further research is anticipated on successful antibiofilm agents. If confirmed as effective and safe in human clinical trials, they may offer a breakthrough in BV treatment. With rising antibiotic resistance, antibiofilm agents will significantly improve the current standard of care for BV management.

Lactobacillus plantarum LPYC225 mixture partially modulates the vaginal bacterial community of Gardnerella vaginalis-infected bacterial vaginosis in mice

Bacterial vaginosis (BV) is defined as dysbiosis of the vaginal microbiome associated with the depletion of Lactobacilli and excessive growth of commensal or pathogenic bacteria. This study investigated the effects of lactic acid bacteria (LAB) mixture (LM; InoRexyne™) on the vaginal bacterial community of Gardnerella vaginalis (G. vaginalis)-infected BV mice. Single LAB and LM exhibited antibacterial and anti-inflammatory effects by inhibiting G. vaginalis growth and pro-inflammatory markers in RAW 264.7 cells. Administering LM did not significantly alter the vaginal architecture or fecal short-chain fatty acids but did significantly inhibit the vaginal interleukin-6 levels in the high LM group compared to the GV group. LM administration decreased the relative abundances of Enterobacter, Escherichia coli, and Bacteroides vulgatus in vaginal flushing fluids compared to the GV group. LM partially alleviated BV by inhibiting G. vaginalis growth and modulating the vaginal bacterial community, providing new insights into its modulatory effects on the vaginal microbiome in BV.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-024-01641-w.

Metronidazole loaded chitosan-phytic acid polyelectrolyte complex nanoparticles as mucoadhesive vaginal delivery system for bacterial vaginosis

Bacterial vaginosis (BV) is a recurring infection that is difficult to treat due to the limited bioavailability of antimicrobials. In this study, Metronidazole (MTZ)-loaded chitosan nanoparticles (MCSNP) were synthesized employing phytic acid (PA) as a crosslinking agent for treating bacterial vaginosis. The prepared MCSNPs were characterized for size, shape, surface charge, compatibility, cytotoxicity, biofilm inhibition, and in-vitro/in-vivo antimicrobial activities. Morphological examination revealed that nanoparticles generated from 0.535 % w/v chitosan and 0.112 % w/v PA were non-spherical, discontinuous, and irregular, with zeta potential ranging from 25.00 ± 0.45 to 39 ± 0.7. The results of DSC and XRD demonstrated no change in the physical state of the drug in the finished formulation. The optimized formulation demonstrates a cumulative drug release of about 98 ± 1.5 % within 8 h. Antimicrobial studies demonstrated that the optimized formulation had enhanced efficacy against acid-adapted BV pathogens, with a MIC value of 0.9 ± 0.1 μg/mL. Compared to the MTZ alone, the in-vivo antibacterial results of in the case of developed nanoparticles showed a four-fold reduction in bacterial count in female Swiss albino mice. Based on the experimental findings, it was concluded that MCSNPs, due to their excellent physiochemical and antibacterial properties, could serve as a potential topical alternative for treating BV.

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.

Synthetic bacterial consortia transplantation for the treatment of Gardnerella vaginalis-induced bacterial vaginosis in mice

Bacterial vaginosis (BV) is a disease caused by vaginal microbiota dysbiosis. Here, we propose the use of synthetic bacterial consortia transplantation (SBCT) for the treatment of Gardnerella vaginalis-induced BV mice. The results showed that SBCT significantly reduced vaginal tissue damage and restored the vaginal microbiota, decreased the secretion of pro-inflammatory cytokines (IL-1β and IL-8), and suppressed NF-κB activation. IL-17, iNOS, and COX-2 expression in vaginal tissue were also down-regulated. However, IL-10 and Foxp3 showed up-regulated expression in mice. Compared with vaginal microbiota transplantation (VMT), results indicated that VMT was more effective than SBCT in suppressing G. vaginalis-induced inflammation. The obtained results suggest that synthetic bacterial consortia might be used as a potential biotherapeutic agent for the treatment of G. vaginalis-induced bacterial vaginosis. Video Abstract.

Assessing the Cervicovaginal Microbiota in the Context of hrHPV Infections: Temporal Dynamics and Therapeutic Strategies

Cervical cancer is the third leading cause of female cancers globally, resulting in more than 300,000 deaths every year. The majority of all cervical cancers are caused by persistent infections with high-risk human papillomaviruses (hrHPV) that can progress to cancer via a series of premalignant lesions. Most women, however, clear this infection within a year, concomitant with disease regression. Both hrHPV clearance and disease regression have been associated with the composition of the cervicovaginal microenvironment, which is defined by the host immune system and the cervicovaginal microbiome (CVM). A healthy microbiome is generally characterized by a high abundance of Lactobacillus species, and a change in the composition may cause bacterial vaginosis (BV), which is associated with an increased susceptibility to persistent hrHPV infections and disease. In this review, the composition of the CVM is discussed, with emphasis on the possible causes that drive changes in the cervicovaginal microbiota in relation to hrHPV infections, disease progression, and disease regression. The literature search focused on the composition of the CVM and its correlation with hrHPV infections and neoplastic lesions as well as the current efforts to adjust the microbiome against adverse viral outcomes.