Gene polymorphisms of NOD1 and interleukin-8 influence the susceptibility to erosive esophagitis in Helicobacter pylori infected Japanese population

Risk factors and 26-years worldwide prevalence of endoscopic erosive esophagitis from 1997 to 2022: a meta-analysis

Erosive esophagitis (EE) is the part of gastroesophageal reflux disease (GERD) spectrum and may progress to esophageal adenocarcinoma. Due to its progressivity and unclear prevalence, we aim to identify the factors contributing in EE to decide the need for further examination. We performed a PRISMA 2020-based systematic search through PubMed and other resources up to June 2, 2022. Study quality was assessed using the Newcastle-Ottawa Scale (NOS). The odds ratio (OR) of each factor and worldwide prevalence of EE were measured. There are 114 observational studies included with a total of 759,100 participants. Out of 29 factors, the significant risk factors are age ≥ 60 y.o. (OR 2.03 [1.81-2.28]), White/Caucasian (OR 1.67 [1.40-1.99]), unmarried (OR 1.08 [1.03-1.14]), having GERD ≥ 5 years (OR 1.27 [1.14-1.42]), general obesity (OR 1.78 [1.61-1.98]), central obesity (OR 1.29 [1.18-1.42]), diabetes mellitus (DM) (OR 1.24 [1.17-1.32]), hypertension (OR 1.16 [1.09-1.23]), dyslipidemia (OR 1.15 [1.06-1.24]), hypertriglyceridemia (OR 1.42 [1.29-1.57]), hiatal hernia (HH) (OR 4.07 [3.21-5.17]), and non-alcoholic fatty liver disease (NAFLD) (OR 1.26 [1.18-1.34]). However, H. pylori infection (OR 0.56 [0.48-0.66]) and atrophic gastritis (OR 0.51 [0.31-0.86]) are protective towards EE. This study demonstrates that age, ethnicity, unmarried, long-term GERD, metabolic diseases, HH, and NAFLD act as risk factors for EE, whereas H. pylori infection and atrophic gastritis act as protective factors. These findings may enable a better understanding of EE and increase greater awareness to address its growing burden.

Dabigatran-induced esophagitis: A case report

RATIONALE

Dabigatran is an anticoagulant medication that has been widely used to prevent strokes caused by atrial fibrillation, deep vein thrombosis, and pulmonary embolism. However, the potential adverse effect of dabigatran of gastrointestinal mucosal injury is often neglected, and even induces esophagitis.

PATIENT CONCERNS

A 77-year-old woman was admitted to the hospital with symptoms of progressive retrosternal pain, upper abdominal discomfort, and dysphagia.

DIAGNOSIS

Esophagogastroduodenoscopy showed longitudinal sloughing mucosal casts in the distal esophagus. Histological examination showed squamous epithelium with neutrophil infiltration, partial epithelial degeneration, and Helicobacter pylori. Based on a literature review, medical history, and imaging examination, the patient was diagnosed with dabigatran-induced esophagitis.

INTERVENTIONS

The patient recovered with standard H. pylori eradication therapy and proton pump inhibitor without discontinuing dabigatran.

OUTCOMES

After 2 weeks, the retrosternal pain and dysphagia were relieved and upper abdominal discomfort was attenuated.

LESSONS

Our case highlights the importance of physicians' awareness of the clinical and endoscopic characteristics of dabigatran-induced esophagitis and the importance of H. pylori-associated tests and eradication if necessary for patients with long-term dabigatran treatment.

Cdx2 Expression and Intestinal Metaplasia Induced by H. pylori Infection of Gastric Cells Is Regulated by NOD1-Mediated Innate Immune Responses

Chronic infection with the bacterial Helicobacter pylori is a major cause of gastric and duodenal ulcer disease, gastric mucosal atrophy, and cancer. H. pylori-induced expression of the intestinal epithelial-specific transcription factor caudal-related homeobox 2 (Cdx2) contributes to intestinal metaplasia, a precursor event to gastric cancer. Given a role for the bacterial pattern recognition molecule nucleotide-binding oligomerization domain 1 (NOD1) in the innate immune response to bacterial infection, we investigated mechanisms used by NOD1 to regulate H. pylori infection and its propensity towards the development of intestinal metaplasia. We found that Cdx2 was induced by H. pylori infection in both normal and neoplastic gastric epithelial cells in a manner that was inversely related to NOD1 signaling. Mechanistic investigations revealed that Cdx2 induction relied upon activation of NF-κB but was suppressed by NOD1-mediated activation of TRAF3, a negative regulator of NF-κB. In vivo, prolonged infection of NOD1-deficient mice with H. pylori led to increased Cdx2 expression and intestinal metaplasia. Furthermore, gastric epithelial cells from these mice exhibited increased nuclear expression of the NF-κB p65 subunit and decreased expression of TRAF3. Overall, our findings illuminated a role for NOD1 signaling in attenuating H. pylori-induced Cdx2 expression in gastric epithelial cells, suggesting a rationale to augment NOD1 signaling in H. pylori-infected patients to limit their risks of accumulating precancerous gastric lesions.

Nucleotide Binding Oligomerization Domain 1 Is an Essential Signal Transducer in Human Epithelial Cells Infected with Helicobacter pylori That Induces the Transepithelial Migration of Neutrophils

Background/Aims

The cytosolic host protein nucleotide binding oligomerization domain 1 (Nod1) has emerged as a key pathogen recognition molecule for innate immune responses in epithelial cells. The purpose of the study was to elucidate the mechanism by which Helicobacter pylori infection leads to transepithelial neutrophil migration in a Nod1-mediated manner.

Methods

Human epithelial cell lines AGS and Caco-2 were grown and infected with H. pylori. Interleukin (IL)-8 mRNA expression and IL-8 secretion were assessed, and nuclear factor κB (NF-κB) activation was determined. Stable transfections of AGS and Caco-2 cells with dominant negative Nod1 were generated. Neutrophil migration across the monolayer was quantified.

Results

Cytotoxin-associated gene pathogenicity island (cagPAI)(+) H. pylori infection upregulated IL-8 mRNA expression and IL-8 secretion in AGS and Caco-2 cells compared with controls. NF-κB activation, IL-8 mRNA expression and IL-8 secretion by cagPAI knockdown strains were reduced compared with those infected with the wild-type strain. NF-κB activation, IL-8 mRNA expression and IL-8 secretion in dominant-negative (DN)-Nod1 stably transfected cells were reduced compared with the controls. The transepithelial migration of neutrophils in DN-Nod1 stably transfected cells was reduced compared with that in controls.

Conclusions

Signaling through Nod1 plays an essential role in neutrophil migration induced by the upregulated NF-κB activation and IL-8 expression in H. pylori-infected human epithelial cells.

NOD1 in contrast to NOD2 functional polymorphism influence Chlamydia trachomatis infection and the risk of tubal factor infertility

Intracellular pattern-recognition receptors NOD1 and NOD2 are capable of sensing common structural units of bacterial walls. Recognition triggers specific immune signalling pathways and leads to pro-inflammatory cytokine upregulation and adequate immune response. We investigated whether two functional polymorphisms in NOD1 and NOD2 exert an effect on susceptibility to (STD patients) and severity of (female patients visiting the fertility clinic) Chlamydia trachomatis infection in 807 Dutch Caucasian women. A significant association of the NOD1 +32656 GG insertion variant with protection against infection with C. trachomatis has been detected [p: 0.0057; OR: 0.52]. When comparing C. trachomatis-positive women without symptoms to C. trachomatis-positive women with symptoms, and to C. trachomatis-positive women with TFI, we observed an increasing trend in carriage of the GG allele [Ptrend: 0.0003]. NOD2 1007fs failed to reveal an association. We hypothesize that the underlying mechanism might be a functional effect of the GG insertion on IFN-beta-dependent regulation of immune response in the genital tract. The research is part of an ongoing effort of identifying key polymorphisms that determine the risk of TFI and effectively translating them into the clinical setting for the purpose of optimizing diagnostic management of women at risk for developing TFI.

Association between interleukin 8 -251 A/T and +781 C/T polymorphisms and osteoarthritis risk

PURPOSE

Interleukin 8 (IL-8), as a member of the CXC chemokine family, has a regulatory role in joint inflammation and cartilage degradation, and contribute to the pathophysiology of osteoarthritis. The aim of the current study was to examine the influence of the IL-8 gene polymorphisms at positions -251 (rs4073) and +781 (rs2227306) on the risk of osteoarthritis.

METHODS

This hospital-based case-control study comprised 150 patients with osteoarthritis and 150 age- and gender-matched controls. IL-8 251 A/T and +781 C/T polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Patients with osteoarthritis had a significantly higher frequency of IL-8 -251 TT genotype [odds ratio (OR)=2.16, 95% confidence interval (CI)=1.09, 4.26; P=0.03], IL-8 -251 T allele (OR=1.41, 95% CI=1.02, 1.94; P=0.04), IL-8 +781 TT genotype (OR=2.79, 95% CI=1.10, 7.08; P=0.03) and IL-8 +781 T allele (OR=1.48, 95% CI=1.02, 2.14; P=0.04) than controls. But the findings are less emphatic by the Bonferroni correction. When stratifying by body mass index, type, articular involvement, and Kellgren-Lawrence grade, no significant differences were found in any groups.

CONCLUSIONS

For the first time, the current data suggested that the TT genotype and T allele of the IL-8 gene polymorphisms at positions -251 and +781 might confer a high risk of osteoarthritis. In the future, additional well-designed large studies were required for the validation of our results.

Helicobacter pylori infection--a boon or a bane: lessons from studies in a low-prevalence population

Helicobacter pylori (H. pylori) infection is etiologically associated with gastric cancer and peptic ulcer diseases which are both important public health burdens which could be largely eliminated by H. pylori eradication. However, some investigators urge caution based on the hypothesis that eradication of H. pylori may result in an increase in the incidence of gastroesophageal reflux disease, esophageal adenocarcinoma, and childhood asthma. The ethnic Malays of northeastern Peninsular Malaysia have long had a low prevalence of H. pylori infection and, as expected, the incidence of gastric cancer and its precursor lesions is exceptionally low. The availability of a population with a low H. pylori prevalence and generally poor sanitation allows separation of H. pylori from the hygiene hypothesis and direct testing of whether absence of H. pylori is associated with untoward consequence. Contrary to predictions, in Malays, erosive esophagitis, Barrett's esophagus, distal esophageal cancers, and childhood asthma are all of low incidence. This suggests that H. pylori is not protective rather the presence of H. pylori infection is likely a surrogate for poor hygiene and not an important source of antigens involved in the hygiene hypothesis. Helicobacter pylori in Malays is related to transmission from H. pylori-infected non-Malay immigrants. The factors responsible for low H. pylori acquisition, transmission, and burden of H. pylori infection in Malays remain unclear and likely involves a combination of environmental, host (gene polymorphisms), and strain virulence factors. Based on evidence from this population, absence of H. pylori infection is more likely to be boon than a bane.