Yeast-based probiotics: Gnosis by Lesaffre sheds light on Quatreflora mechanisms

20 May 2020 --- Gnosis by Lesaffre is highlighting a new review detailing the potential mechanisms of its Saccharomyces cerevisiae CNCM I-3856 strain, called Quatreflora Biotic, for vaginal infections caused by fungi and bacteria. The explored mechanisms include the inhibition of pathogen growth and adherence to epithelial cells, immunomodulatory activity, inhibition of filamentation and biofilm development, and the reduction of toxin production. This information adds to increasing understanding of novel avenues to fight vaginal infections, which affect a majority of women.

“Vaginal infections affect 70 percent of women during their lifetimes and account for millions of annual doctors’ visits. These infections are predominantly represented by vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV). Although standard antimicrobial agents remain the major strategy for the prevention and treatment of vaginal infections, both VVC and BV are difficult to treat due to high rates of resistance and recurrence, high probability of complications and negative effects on the vaginal microbiota,” the researchers write in their review article.

The review assessed a host of investigations into yeast-based probiotics as a novel therapeutic approach. Gnosis by Lesaffre details that several scientific publications have explained why interest around the use of yeast-based probiotics has increased over the last few years. This type of prebiotic are naturally resistant to antibiotics, so it is not necessary to evaluate their antibiotic resistance profile. This also means that they can be used by patients undergoing antibiotic therapy. “Due to these characteristics, yeast probiotics provide a considerable advantage over bacterial-origin probiotics,” the company states. 

The researchers also used an in vivo imaging system in a mouse model of VVC to explore the effects of daily intravaginal administration of Quatreflora on C. albicans clearance. It was found that the live version – and to a lesser degree the inactivated probiotic – elicited clearance at levels similar to those obtained with fluconazole, which is the conventional drug used to treat the condition.

Potential as an adjuvant therapeutic approach
Additionally, the intravaginal administration of the live strain was found to downregulate the production of interleukin (IL)-8, a neutrophil chemotactic factor, which plays a role in the pathogenesis of human VVC. Notably, the researchers also demonstrated for the first time that vaginal administration of the strain had beneficial effects in a mouse model of G. vaginalis infection.

“Probiotic administration could represent an alternative or adjuvant therapeutic approach for preventing or treating VVC and BV. Despite several preclinical pieces of research and a multitude of clinical trials, to date, few studies have analyzed the effects of yeast-based probiotics on vaginal infections. This is the first overview of the beneficial effects of a probiotic yeast in preventing or treating some vaginal mucosal infections,” state the researchers. 

They concluded that the discovered features open the door to future clinical studies to determine if Quatreflora can reduce the colonization of C. albicans or G. vaginalis on human mucosal surfaces. Further avenues of exploration include seeing if it can attenuate VVC or BV symptoms and enhance the antimicrobial effect of standard therapeutic approaches.

This review is not the first time Quatreflora has come under the microscope. A prior controlled clinical trial in women with vaginal candidiasis confirmed Quatreflora’s positive effects. The mechanism appears to be associated with a direct effect of S. cerevisiae on pathogens, as well as, in the case vulvovaginitis, with its immunobiotic properties. The results of this trial saw Quatreflora decrease the risk of recurrence by 54 percent, as well as confirming its efficacy in accelerating C. albicans clearance after two months.

Gnosis by Lesaffre also presented a randomized pilot clinical poster at Probiota Americas in Canada last summer. It shows the positive results of the migration of Quatreflora Biotic from the intestine to the vagina after oral administration.

Edited by Katherine Durrell