# Probiotic Modulation of the Gut–Ovary and Gut–Myometrium Axes: An In Vitro Study

## TL;DR

This study shows that a combination of probiotics can improve gut and reproductive health by enhancing cell function and reducing inflammation.

## Contribution

The novel contribution is demonstrating synergistic effects of a multi-strain probiotic on gut-reproductive axis interactions in vitro.

## Key findings

- The combined probiotic improved myometrial proliferation by up to ~78% and decreased ROS and TNF-α levels significantly.
- The probiotic mixture activated ERK/MAPK and PI3K/AKT pathways in ovarian cells and increased LH and FSH secretion.
- The probiotic blend enhanced butyrate production by ~23–51% and improved intestinal cell viability and barrier function.

## Abstract

Emerging evidence suggests that gut microbiota significantly influence female reproductive health by affecting hormonal, immune and metabolic processes. This research explored how a probiotic blend comprising Lactobacillus crispatus novaLCR6, Limosilactobacillus fermentum novaLF58 and Bifidobacterium bifidum novaBBF9 affects the gut–myometrium and gut–ovary axes. Intestinal epithelial cells were exposed to individual probiotics or their combination using a Transwell® setup; their effects on barrier integrity, probiotic activity and short-chain fatty acid production were measured. Subsequently, basolateral metabolites were applied to myometrial and ovarian cells to assess viability, proliferation, oxidative stress, inflammation, signalling pathways and hormone production. All probiotics enhanced intestinal cell viability and barrier function. The combined probiotic showed synergistic effects, enhancing butyrate production by ~23–51%, improving myometrial proliferation by up to ~78%, decreasing ROS and TNF-α levels by ~49% and ~74% and modulating oxytocin signalling. In ovarian cells, the probiotic mixture activated ERK/MAPK and PI3K/AKT pathways, normalised PAK1, ERβ and PAX8 expressions and significantly increased LH and FSH secretion compared to single strains. These findings suggest that a multi-strain probiotic may modulate pathways involved in reproductive tissue homeostasis through gut–reproductive axis interactions, providing mechanistic insight from an in vitro study.