The Influence of Helicobacter pylori on Human Gastric and Gut Microbiota

Abstract

Helicobacter pylori is a Gram-negative bacterium that is able to colonize the human stomach, whose high prevalence has a major impact on human health, due to its association with several gastric and extra-gastric disorders, including gastric cancer. The gastric microenvironment is deeply affected by H. pylori colonization, with consequent effects on the gastrointestinal microbiota, exerted via the regulation of various factors, including gastric acidity, host immune responses, antimicrobial peptides, and virulence factors. The eradication therapy required to treat H. pylori infection can also have detrimental consequences for the gut microbiota, leading to a decreased alpha diversity. Notably, therapy regimens integrated with probiotics have been shown to reduce the negative effects of antibiotic therapy on the gut microbiota. These eradication therapies combined with probiotics have also higher rates of eradication, when compared to standard treatments, and are associated with reduced side effects, improving the patient’s compliance. In light of the deep impact of gut microbiota alterations on human health, the present article aims to provide an overview of the complex interaction between H. pylori and the gastrointestinal microbiota, focusing also on the consequences of eradication therapies and the effects of probiotic supplementation.

Exploring the Link between Helicobacter pylori, Gastric Microbiota and Gastric Cancer

“…H. pylori infection negatively correlates with the alpha diversity of gastric microbiota and effectively clusters groups of infected and uninfected individuals based on the beta diversity [ 39 ]. In particular, H. pylori is accompanied by a lower abundance of Actinobacteria , Bacteroidetes , and Firmicutes and an increase in Proteobacteria [ 40 , 41 , 42 ]. Furthermore, there exists a negative association between H. pylori and some gastric members, such as Acidovorax , Aeromonas , Bacillus , Bradyrhizobium , Halomonas , Cloacibacterium , Meiothermus , Methylobacterium , and Ralstonia , while the interactions of the non- H. pylori members are positively correlated [ 43 ].…”

Therapeutic Approach Targeting Gut Microbiome in Gastrointestinal Infectious Diseases

“…pylori affects the host gastrointestinal environment using various mechanisms. By producing urease and multiple virulence factors such as vacuolating cytotoxin A (VacA) and high-temperature requirement A (HtrA), H. pylori disrupt the host cell junctions and epithelial barrier, damages host cells, and suppresses the host immune system [11,12]. H. pylori brings about significant changes to the gastrointestinal environment (for example, an increase in pH) and predictably influences the gut microbiota extensively [13].…”

Bioactive peptides as alternative treatment for Helicobacter pylori infection

“…Furthermore, the pathogen dynamics with the microbiota of the gastrointestinal tract is highly complex, and eradication not only affects the gastrointestinal tract itself, but also its absence has been associated with dysbiosis and the emergence of a variety of systemic disorders, weight gain or loss, and susceptibility to allergic diseases such as asthma [43,[74][75][76][77][78][79]. In contrast, research over the years has demonstrated that eradicating H. pylori prior to the onset of precancerous histological changes can prevent the development of gastric cancer and dysbiosis can be managed with the integration to the antibiotic treatment of probiotics and other alternatives for microbiota modulation [80][81][82].…”