Novel virulence factor <i>dupA</i> of <i>Helicobacter pylori</i> as an important risk determinant for disease manifestation: An overview

Liu

Front. Cell. Infect. Microbiol.

et al. 2023

Helicobacter pylori is believed to induce gastropathy; however, the exact pathogenic molecules involved in this process have not been elucidated. Duodenal ulcer promoting gene A (DupA) is a virulence factor with a controversial role in gastric inflammation and carcinogenesis. To explore and confirm the function of DupA in gastropathy from the perspective of the microbiome, we investigated the microbial characteristics of 48 gastritis patients through 16S rRNA amplicon sequencing. In addition, we isolated 21 H. pylori strains from these patients and confirmed the expression of dupA using PCR and qRT-PCR. Bioinformatics analysis identified diversity loss and compositional changes as the key features of precancerous lesions in the stomach, and H. pylori was a characteristic microbe present in the stomach of the gastritis patients. Co-occurrence analysis revealed that H. pylori infection inhibits growth of other gastric inhabiting microbes, which weakened the degradation of xenobiotics. Further analysis showed that dupA+ H. pylori were absent in precancerous lesions and were more likely to appear in erosive gastritis, whereas dupA− H. pylori was highly abundant in precancerous lesions. The presence of dupA in H. pylori caused less disturbance to the gastric microbiome, maintaining the relatively richness of gastric microbiome. Overall, our findings suggest that high dupA expression in H. pylori is correlated with a high risk of erosive gastritis and a lower level of disturbance to the gastric microbiome, indicating that DupA should be considered a risk factor of erosive gastritis rather than gastric cancer.

Section: Discussionsupporting

confidence: 91%

dupA+H. pylori reduces diversity of gastric microbiome and increases risk of erosive gastritis

Liu

Front. Cell. Infect. Microbiol.

et al. 2023

“…H. pylori , a Gram-negative bacterium infecting 50% of the world population, possesses multiple virulence factors, such as proteins CagA, VacA and DupA [ 1 , 2 , 3 , 4 ], making it a primary pathogen associated to various gastric pathologies including peptic ulcer, mucosa-associated gastric lymphoma and gastric cancer [ 5 ]. This pathogen has also been associated to extra-gastric pathologies, such as hyperemesis gravidarum, ischemic stroke, Alzheimer’s disease, rosacea and iron deficiency anemia, Non-alcoholic fatty liver disease and open-angle glaucoma [ 6 , 7 , 8 , 9 , 10 , 11 ].…”

Section: Introductionmentioning

confidence: 99%

Intracellular Presence of Helicobacter pylori and Its Virulence-Associated Genotypes within the Vaginal Yeast of Term Pregnant Women

et al. 2021

Background: Helicobacter pylori transmission routes are not entirely elucidated. Since yeasts are postulated to transmit this pathogen, this study aimed to detect and genotype intracellular H. pylori harbored within vaginal yeast cells. Methods: A questionnaire was used to determine risk factors of H. pylori infection. Samples were seeded on Sabouraud Dextrose Agar and horse blood-supplemented Columbia agar. Isolated yeasts were identified using and observed by optical microscopy searching for intra-yeast H. pylori. Total yeast DNA, from one random sample, was extracted to search for H. pylori virulence genes by PCR and bacterial identification by sequencing. Results: 43% of samples contained yeasts, mainly Candida albicans (91%). Microscopy detected bacteria such as bodies and anti-H. pylori antibodies binding particles in 50% of the isolated yeasts. Total DNA extracted showed that 50% of the isolated yeasts were positive for H. pylori 16S rDNA and the sequence showed 99.8% similarity with H. pylori. In total, 32% of H. pylori DNA positive samples were cagA+ vacAs1a vacAm1 dupA−. No relationship was observed between possible H. pylori infection risk factors and vaginal yeasts harboring this bacterium. Conclusion: H. pylori having virulent genotypes were detected within vaginal yeasts constituting a risk for vertical transmission of this pathogen.

“…DupA is a H. pylori virulence factor with multifunctional biological activities, and it can be considered an essential biomarker in duodenal ulcer (DU) (Alam et al 2020 ). The prevalence of the DupA gene in strains was higher in patients with duodenal ulcers than in patients with gastritis or gastric cancer (Ansari and Yamaoka 2017 ).…”

Section: Status Pathogenesis and Treatment Of H Pylori ...mentioning

confidence: 99%

The impacts of probiotics in eradication therapy of Helicobacter pylori

Bai

Zhu

et al. 2022

Arch Microbiol

Helicobacter pylori (H. pylori) is a well-known pathogen that infects approximately half of the world’s population. It is a pathogenic agent with potential health hazards related to diverse diseases, especially digestive diseases, such as chronic gastritis, peptic ulcer, and gastric carcinoma. In clinical, antibiotics are commonly applied in eradication therapy of H. pylori. However, the increase in antibiotic resistance and side effects has induced the failure of eradication therapy. Recent studies have shown that probiotic supplementation has promising application prospects. It can restore the gastrointestinal microbiota balance and prevent dysbacteriosis caused by antibiotics. Furthermore, it has been reported to have direct or indirect inhibitory effects on H. pylori. Probiotics may have a beneficial effect on H. pylori eradication. However, the strain, dosages, duration times, and safety of probiotic supplementation need further study before clinical applications.