# The effects of postbiotics and glycyrrhetinic acid on immune response and inflammation-related genes during H. pylori eradication therapy

## TL;DR

This study shows that postbiotics and glycyrrhetinic acid can reduce inflammation and H. pylori bacterial load in gastric cells and rat models.

## Contribution

The study introduces a novel combination of postbiotics and glycyrrhetinic acid as potential adjuncts for H. pylori eradication therapy.

## Key findings

- Postbiotics from S. thermophilus and L. casei reduced NF-κB and TNF-α expression by up to 10-fold in AGS cells.
- The quaternary treatment group achieved complete H. pylori eradication with zero detectable bacterial load in rat models.
- Combination treatments showed significant reductions in proinflammatory cytokines like IL-1β, IL-6, and IL-8.

## Abstract

This study aims to test the effectiveness of postbiotics from Streptococcus thermophilus and Lactobacillus casei, along with Glycyrrhetinic acid, against H. pylori in both AGS cells (a human gastric adenocarcinoma cell line) and an experimental rat gastritis model.

The effectiveness of the compounds (postbiotics and G. acid) against H. pylori was evaluated by measuring the expression levels of various genes, including NF-κB, IL-1β, IL-6, IL-8, IL-10, TNF-α, COX-2, FOX-M1, and IL-33 in AGS cells using the Real-Time PCR method. Additionally, bacterial loads in gastric tissue were quantified using culture-based colony-forming unit (CFU) analysis and expressed as log₁₀ CFU/g. The study also evaluated the effectiveness of combinations of these components in the rat gastritis model through microbiological and histopathological analyses.

The postbiotics of S. thermophilus and L. casei have shown a significant reduction in the expression level of NF-κB when compared to the control group. The S. thermophilus plus L. casei treatment group showed a 10-fold decrease in NF-κB expression, while the G. acid plus L. casei treatment group showed a 5-fold decrease. TNF-α expression levels were also lower in the S. thermophilus and L. casei treatment groups with 10-fold and 5-fold reductions, respectively. The expression of IL-1β was significantly reduced in all treatment groups compared to the control group, with a 10-fold decrease in expression. The S. thermophilus plus L. casei treatment group exhibited a 10-fold reduction in IL-6 release, a proinflammatory cytokine. Similarly, the expression of IL-8 was reduced by 10-fold and 2-fold in the S. thermophilus and L. casei treatment groups, respectively. Additionally, bacterial loads in gastric tissue were quantified using culture-based colony-forming unit (CFU) analysis and expressed as log₁₀ CFU/g. The mean bacterial load in the infected control group was 6.14 ± 0.18 log₁₀ CFU/g, while the quaternary treatment group (S. thermophilus + L. casei + G. acid + antibiotic) achieved complete eradication with no detectable colonies (0.00 ± 0.00 log₁₀ CFU/g). Ternary and binary treatment groups exhibited intermediate bacterial loads, ranging from approximately 1.63 ± 0.09 to 3.24 ± 0.17 log₁₀ CFU/g, indicating partial efficacy compared to the control group.

These promising findings can pave the way for the development of novel therapeutic approaches for treating H. pylori-associated gastritis. The combination of molecular (gene expression) and microbiological (CFU) data demonstrates the multi-dimensional efficacy of postbiotics and glycyrrhetinic acid as potential adjunctive agents.

The online version contains supplementary material available at 10.1186/s12866-025-04191-1.