Latest Research: Postbiotics Inhibit Helicobacter pylori, Helping White-Collar Workers Combat the "Invisible Overtime" Monster in Their Stomachs! Part 2

Bioyitech's Chief Scientist, Professor Zhang Lanwei and Lecturer Zhang Zhe from the Ocean University of China Team: Postbiotics Inhibit the Adhesion and Survival of Helicobacter pylori through a Co-Aggregation Mechanism.

Research Findings

In this study, Helicobacter pylori was used as the specific pathogen, and in vitro co-aggregation experiments were conducted on 35 strains of postbiotics to evaluate their co-aggregation ability with H. pylori. The results showed that the co-aggregation rates ranged mainly between 10% and 80%, with five strains (Lactobacillus rhamnosus MN45, LactoBacillus fermentum YNM1-1, Lactobacillus acidophilus D-L, Lactobacillus reuteri M07, and Lactobacillus fermentum YNM7-2) exhibiting the highest co-aggregation rates. Compared to the positive control strain DSM17648, the co-aggregation rates of these five strains were significantly higher (P < 0.05).

Figure 3. Scanning electron microscopy (SEM) analysis of postbiotic-Helicobacter pylori co-aggregates. Magnification: 5000× (left) and 10000× (right), with scale bars indicated in the images. (A) H. pylori group; (B) DSM17648 group; (C) MN45 group; (D) YNM1-1 group; (E) D-L group.

Under confocal laser scanning microscopy (CLSM) observation, DAPI-stained cell nuclei appeared blue, while H. pylori labeled with CFDA-SE emitted green fluorescence (Figure 4). After 2 hours of treatment, compared to the untreated control group (Figure 4A), the adhesion amount of H. pylori was significantly reduced in the MN45 group (Figure 4C), YNM1-1 group (Figure 4D), and D-L group (Figure 4E), with the MN45 group exhibiting the most pronounced inhibitory effect (Figure S1B). In contrast, the positive control group treated with DSM17648 showed only a slight reduction in adhesion (Figure 4B).

Figure 4. Confocal laser scanning microscopy (CLSM) analysis of postbiotics inhibiting H. pylori adhesion to AGS cells via co-aggregation. H. pylori was labeled with CFDA-SE (green), and cell nuclei were counterstained with DAPI (blue). (A) H. pylori group, (B) DSM17648 group, (C) MN45 group, (D) YNM1-1 group, (E) D-L group.

To investigate the genetic basis underlying the differences in co-aggregation ability between postbiotics and H. pylori, this study performed whole-genome sequencing and comparative genomic analysis on the strain with the highest co-aggregation rate, MN45, and a homologous strain with lower co-aggregation ability, SLT1. Functional annotation using Clusters of Orthologous Groups (COG) revealed that the core genes of MN45 (Figure 5F) and SLT1 (Figure 5G) are primarily involved in essential cellular functions, such as amino acid transport and metabolism (E), carbohydrate transport and metabolism (G), translation, ribosomal structure and biogenesis (J), transcription (K), cell wall/membrane/envelope biogenesis (M), and general function prediction only (R). To identify differences in gene function, we compared the COG copy numbers between strains and generated a heatmap of genes with higher copy numbers in MN45 (Figure 5H). Significant differences were found in five COG categories: COG1396, COG3293, COG0583, COG2826, and COG1299. Among these, COG1396 (Category K, transcription) was particularly enriched in MN45, with 23 copies, which is three more than in SLT1. According to NCBI annotation, COG1396 encodes a transcriptional regulator containing an XRE family helix-turn-helix (HTH) domain.

Figure 5. Investigation of the co-aggregation mechanism between postbiotics and Helicobacter pylori. (A) CGView circular genome map of MN45; (B) CGView circular genome map of SLT1; (C) Phylogenetic tree based on 16S rRNA; (D) Collinearity analysis of MN45 and SLT1; (E) Venn diagram of shared genes between MN45 and SLT1; (F) COG functional classification and statistics of proteins encoded by the MN45 genome; (G) COG functional classification and statistics of proteins encoded by the SLT1 genome; (H) Heatmap of COGs.

This study utilized a simulated gastric fluid model to screen for postbiotics capable of co-aggregating with Helicobacter pylori, and confirmed the formation of interconnected aggregate structures through Confocal Laser Scanning Microscopy (CLSM) and Scanning Electron Microscopy (SEM). The research found that three strains with strong co-aggregation ability (MN45, YNM1-1, and D-L) significantly inhibited the adhesion of H. pylori in an AGS cell model, with MN45 exhibiting the most pronounced effect. Furthermore, these postbiotics reduced urease activity and related gene expression in cells infected with H. pylori, inhibited the expression of virulence factors, and alleviated the host inflammatory response. Further investigation revealed that co-aggregation efficiency increased rapidly over time before stabilizing and remained stable under gastric acid conditions. Although MN45 and SLT1 are phylogenetically closely related and their genomes exhibit high collinearity, comparative genomic analysis showed that MN45 possesses amplified gene copy numbers in several functional categories, particularly COG1396 related to transcription. This suggests that the amplification of XRE family transcriptional regulators may enhance the co-aggregation ability with H. pylori by upregulating adhesion-related genes.

Compared to previous studies that primarily focused on in vitro co-aggregation and clinical efficacy, this research systematically screened and validated postbiotics with excellent co-aggregation ability, virulence factor inhibition, and anti-inflammatory effects, highlighting their unique mechanism of action and therapeutic potential. These findings provide new insights into postbiotic-based interventions for H. pylori and offer support for microbiota-targeted therapies.