(Left) Microbiota of recurrent cystitis is significantly different from that of uncomplicated cystitis and healthy vaginal microbiota. (Right) But, the microbiota of recurrent cystitis is similar to that of the prevention group, which used vaginal suppositories containing Lactobacilli.
Newswise — A team of researchers from Okayama University in Japan conducted a study to investigate the relationship between vaginal microbiota and recurrent cystitis (RC) in postmenopausal women. RC is a common urinary tract and bladder infection that affects many women after menopause. The study aimed to understand the changes in the vaginal microbiota that contribute to RC and to evaluate the therapeutic effect of Lactobacillus-containing vaginal suppositories in this specific group of women.
Previous research has shown that alterations in the vaginal microbiota play a crucial role in the development of urinary tract infections (UTIs). In UTIs, there is a decrease in the beneficial bacteria, such as Lactobacilli, and an increase in pathogenic bacteria like Escherichia coli (E. coli). Some clinical trials have demonstrated the effectiveness of Lactobacillus-containing vaginal suppositories in preventing RC. However, it remains unknown whether postmenopausal women, whose vaginal microbiota undergoes changes due to menopause, can also benefit from these suppositories. Additionally, there is a lack of studies comparing the vaginal microbiota in postmenopausal women with RC and uncomplicated cystitis to that of healthy postmenopausal women. Furthermore, no studies have examined the changes in the vaginal microbiota during the intervention with Lactobacillus-containing vaginal suppositories in women with RC.
To address these gaps, the team of scientists, led by Mr. Takanori Sekito and supported by Dr. Takuya Sadahira, Dr. Motoo Araki from the Department of Urology, and Dr. Shuta Tomida from the Center for Comprehensive Genomic Medicine at Okayama University, compared the vaginal microbiota of postmenopausal women with and without RC. They also examined the relative abundance of different bacterial species in the vagina before and after the administration of Lactobacillus crispatus-containing vaginal suppositories, which had been previously developed by the team. This allowed them to assess the therapeutic effect of Lactobacillus in this specific group of women.
The results of the study were published in Volume 14 of the journal Frontiers in Microbiology on 18 May 2023.
The researchers employed 16S ribosomal ribonucleic acid (rRNA)-based gene sequencing to analyze the bacterial community in vaginal samples obtained from different groups: healthy postmenopausal women, postmenopausal women with RC, postmenopausal women with uncomplicated cystitis, and postmenopausal women receiving Lactobacillus crispatus-containing vaginal suppositories for RC prevention. Their findings revealed significant differences in bacterial species between the healthy group and the uncomplicated cystitis group, despite some apparent similarities in their respective bacterial communities. Moreover, both the uncomplicated cystitis group and the healthy group exhibited distinctly different microbiomes compared to the RC group.
Comparing the vaginal microbiomes of the RC group and the prevention group, the researchers noted similarities in bacterial species diversity but observed variations in their relative abundance. Interestingly, no Lactobacilli were detected in the vaginal samples of postmenopausal women with RC. Instead, the dominant species belonged to the Enterobacteriaceae family, which includes numerous uropathogenic bacteria. This is in stark contrast to the healthy vaginal microbiota, which is characterized by an abundance of beneficial bacteria like Lactobacilli. Notably, the relative abundance of Lactobacilli in the RC prevention group was significantly higher (19%) than in the RC group, thanks to the administration of suppositories.
Mr. Sekito remarks, "We discovered that the vaginal microbiota in postmenopausal women with recurrent cystitis differs significantly from that in postmenopausal women with uncomplicated cystitis or healthy women." The study demonstrates that RC occurs when Lactobacilli, crucial members of a healthy vaginal microbiota, are depleted and replaced by pathogenic bacteria like E. coli. The current treatment approach for RC involves antimicrobial agents, which are susceptible to antibiotic resistance. This research suggests an alternative therapeutic avenue through the use of vaginal suppositories containing Lactobacilli, which can help restore balance to the vaginal microbiota and, consequently, reduce the occurrence of RC.
Furthermore, frequent use of antimicrobials in cases of recurring infections can even lead to more severe forms of cystitis that are challenging to treat. Mr. Sekito concludes, "Lactobacillus vaginal suppositories have the potential to serve as a novel preventive method for the numerous individuals suffering from recurrent cystitis, a condition that cannot be adequately cured by taking antimicrobials."
RSS