Progress in elucidating the relationship between Helicobacter pylori infection and intestinal diseases

Abstract

Helicobacter pylori ( H. pylori ) infection causes changes to the intestinal flora, such as small intestinal bacterial overgrowth, and increases gastric acid secretion-stimulating gastrointestinal hormones, mainly gastrin, due to a decrease in gastric acid caused by atrophic gastritis. In addition, the cellular components of H. pylori travel through the intestinal tract, so the bacterial infection affects the immune system. Therefore, the effects of H. pylori infection are observed not only in the stomach and the proximal duodenum but also in the small and large intestines. In particular, meta-analyses reported that H. pylori -infected individuals had an increased risk of colorectal adenoma and colorectal cancer. Moreover, a recent study reported that the risk of developing colorectal cancer was increased in subjects carrying H. pylori vacuolating cytotoxin A antibody. In addition, it has been reported that H. pylori infection exacerbates the symptoms of Fabry’s disease and familial Mediterranean fever attack and is involved in irritable bowel syndrome and small intestinal ulcers. On the other hand, some studies have reported that the frequency of ulcerative colitis, Crohn’s disease, and celiac disease is low in H. pylori -infected individuals. Thus, H. pylori infection is considered to have various effects on the small and large intestines. However, few studies have reported on these issues, and the details of their effects have not been well elucidated. Therefore, additional studies are needed.

Helicobacter pylori and Alzheimer’s Disease-Related Metabolic Dysfunction: Activation of TLR4/Myd88 Inflammation Pathway from p53 Perspective and a Case Study of Low-Dose Radiation Intervention

“…Although H. pylori is commonly found in the gastric area with acid environment, a recent study has demonstrated that H. pylori may participate in the development of inflammatory disease through regulating of the intestinal microbiota . For instance, H. pylori infection causes small intestinal bacterial overgrowth and increases gastric acid secretion; meanwhile, H. pylori infection is observed in the stomach and the proximal duodenum and the small and large intestines . It has been found that H. pylori infection is a risk factor for small intestinal ulcerative lesions .…”

“…55 For instance, H. pylori infection causes small intestinal bacterial overgrowth and increases gastric acid secretion; meanwhile, H. pylori infection is observed in the stomach and the proximal duodenum and the small and large intestines. 56 It has been found that H. pylori infection is a risk factor for small intestinal ulcerative lesions. 57 In this study, we observed IRS-1 and Akt expression not changed in the AD + LDR group vs AD + MD + LDR group.…”

Epidemiological, clinical, and histological presentation of celiac disease in Northwest China

“…This finding is similar to that of Gungor et al [ 40 ]. However, it has been reported that in individuals without CD, H. pylori infection itself can cause duodenal mucosal damage[ 41 ]. In a study by Konturek et al [ 42 ], the prevalence of H. pylori infection was higher in patients with CD than in controls[ 42 ].…”

Relationship between Helicobacter pylori infection and gastrointestinal microecology

“…Studies have shown that H. pylori infection can not only affect the gastric microecology but also change the intestinal flora. The relationship between H. pylori infection and intestinal microecology is still not clear, and the conclusions in the literature are controversial ( Fujimori, 2021 ). A study on children showed that the abundance and diversity of gastrointestinal flora were higher in children without H. pylori infection, among which Proteobacteria, Bacteroides, Clostridium, etc., w ere more abundant ( Llorca et al., 2017 ).…”

“…An imbalance in H. pylori -related intestinal flora can lead to the occurrence of nonalcoholic fatty liver disease (NAFLD), colorectal adenoma, irritable bowel syndrome and small intestinal ulcer, and the mechanism may be that H. pylori invades the intestinal mucosa to increase intestinal permeability and leads to an imbalance of intestinal flora, which facilitates the entry of bacterial endotoxins into the liver through the portal vein, thereby promoting intestinal inflammation ( Santos et al., 2020 ; Fujimori, 2021 ). It also affects the absorption of iron and vitamin B12 in the intestinal tract and the metabolic process of carbohydrates and amino acids in the host ( Santos et al., 2020 ).…”