Role of Acid Suppression in Acid-related Diseases: Proton Pump Inhibitor and Potassium-competitive Acid Blocker

The effect of Channa striata extract and standard eradication regimen on asymmetric dimethylarginine in Helicobacter pylori gastritis rat model

BACKGROUND AND AIM

The presence of gastric mucosa or submucosa inflammation due to Helicobacter pylori leads to histological changes. Gastric injury, pro-inflammatory factors, and oxidative stress in H. pylori infection produce asymmetric dimethylarginine (ADMA), which are a competitive inhibitor of nitric oxide synthase. Investigations were carried out aimed at finding new drugs derived from natural products for the treatment of H. pylori. Channa striata is known to have in vitro anti-inflammatory and antimicrobial properties. This study aimed to investigate the effect of C. striata extract and a standard eradication regimen on ADMA levels and histological changes in the H. pylori gastritis rat model.

MATERIALS AND METHODS

Thirty-five male rats were randomly and equally divided into five groups. Group-1 was the negative control group and Groups-2 to 5 were H. pylori-infected groups. Groups-3 to 5 were administered C. striata extract, a standard eradication regimen, and a combination of standard eradication regimen and C. striata extract, respectively. Histological examination and serum ADMA levels were analyzed. The difference between groups was analyzed using the Kruskal-Wallis and one-way analysis of variance tests. The significance was p<0.05.

RESULTS

Serum ADMA levels and severity of gastritis were higher in infected groups compared to the negative control group (p<0.05). The severity of gastritis and mean ADMA levels in the group that received a single administration of the C. striata extract was higher than the others (p<0.05). Serum ADMA levels and severity of gastritis were significantly reduced in the group that received a combination of standard eradication regimen and C. striata extract (p<0.05).

CONCLUSION

Single administration of C. striata extract worsens the severity of gastritis and increased serum ADMA levels in the H. pylori gastritis rat model. The administration of a combination of standard eradication regimen and C. striata extract reduces serum ADMA levels and significantly improves the severity of H. pylori gastritis rat model.

Antimicrobial and Antibiofilm Activities of New Synthesized Silver Ultra-NanoClusters (SUNCs) Against Helicobacter pylori

Helicobacter pylori colonizes approximately 50% of the world's population, and it is the cause of chronic gastritis, peptic ulcer disease, and gastric cancer. The increase of antibiotic resistance is one of the biggest challenges of our century due to its constant increase. In order to identify an alternative or adjuvant strategy to the standard antibiotic therapy, the in vitro activity of newly synthesized Silver Ultra-NanoClusters (SUNCs), characterized by an average size inferior to 5 nm, against clinical strains of H. pylori, with different antibiotic susceptibilities, was evaluated in this study. MICs and MBCs were determined by the broth microdilution method, whereas the effect of drug combinations was determined by the checkerboard assay. The Minimum Biofilm Eradication Concentration (MBEC) was measured using AlamarBlue (AB) assay and colony-forming unit (CFU) counts. The cytotoxicity was evaluated by performing the MTT assay on the AGS cell line. The inhibitory activity was expressed in terms of bacteriostatic and bactericidal potential, with MIC50, MIC90, and MBC50 of 0.33 mg/L against planktonic H. pylori strains. Using the fractional inhibitory concentration index (FICI), SUNCs showed potential synergism with metronidazole and clarithromycin. The biofilm eradication was obtained after treatment with 2×, 3×, and 4× MIC values. Moreover, SUNCs showed low toxicity on human cells and were effective in eradicating a mature biofilm produced by H. pylori. The data presented in this study demonstrate that SUNCs could represent a novel strategy for the treatment of H. pylori infections either alone or in combination with metronidazole.

The effect of snakehead fish extract supplementation to first-line eradication regimen on macrophage migration inhibitory factor (MIF) expression in rats induced by Helicobacter pylori infection

Objective:

This work was organized to assess macrophage migration inhibitory factor (MIF) expression in snakehead fish extract supplementation to first-line eradication regimen in rats induced by Helicobacter pylori infection.

Materials and methods:

A total of 28 manly rats were haphazardly isolated equally into four groups. Group-1 was the control negative, and groups-2–4 were H. pylori-infected groups. Group-2 was the control positive. Groups-3 and 4 were treated with first-line eradication regimen and first-line eradication regimen supplemented with snakehead fish extract, respectively. Immunoreactive scores (IRS) of MIF expression and eradication testing procedure were carried out. The comparison and difference between groups were analyzed by Kruskal–Wallis and post hoc Mann–Whitney U-test. A value of p < 0.05 was considered to be a limit of significance.

Results:

The average IRS of MIF expression in group-2 was the highest among other groups (p < 0.05). Group-4 (supplemented by snakehead fish extract) had a lower median value IRS of MIF expression compared to group-3 [1.0 (0.0–2.0) vs. 3.5 (2.0–6.0), p = 0.004].

Conclusion:

MIF expression was higher in rats induced by H. pylori infection. Snakehead fish extract supplementation to first-line eradication regimen significantly reduces more MIF expression compared to a single administration of first-line eradication regimen in rats induced by H. pylori infection.

Vonoprazan Fumarate for the Treatment of Gastric Ulcers: A Short Review on Emerging Data

Potassium-competitive acid blockers (P-CABs), such as vonoprazan, represent a novel and heterogeneous class of drugs that competitively block the potassium binding site of gastric H+/K+ ATPase, thus potentially overcoming the limitations of proton-pump inhibitors. Different studies evaluated the efficacy of vonoprazan versus proton-pump inhibitors (PPIs) for the treatment of acid-related disorders, and, therefore, P-CABs present the same indications of PPIs: gastroesophageal reflux disease, gastric and duodenal ulcer healing, management of upper gastrointestinal bleeding, non-steroidal anti-inflammatory drug (NSAID)-associated ulcers and Helicobacter pylori eradication therapy. The aim of this review was to evaluate the role of vonoprazan for the treatment of peptic ulcer disease (PUD) and the management of gastric ulcer occurring after endoscopic submucosal dissection (ESD). Indeed, vonoprazan (at the dose of both 10 and 20mg) showed similar results to PPIs in patients taking long-term NSAIDs, in the absence of severe adverse effects, and provided a more rapid and effective treatment of ulcers induced by ESD. However, studies in medical literature are heterogeneous, mainly performed with a retrospective design, and often carried out in Japan only. For these reasons, further prospective, randomized studies are warranted in order to help physicians, patients, and policymakers regarding the use of vonoprazan in clinical practice.

Changes of gastric ulcer bleeding in the metropolitan area of Japan

BACKGROUND

The two main causes of gastric ulcer bleeding are Helicobacter pylori (H. pylori) infection and ulcerogenic medicines, although the number of cases caused by each may vary with age. In Japan, the rate of H. pylori infection has fallen over the last decade and the number of prescriptions for non-steroidal anti-inflammatory drugs (NSAIDs) and antithrombotic drugs is increasing as the population ages. Methods of treatment for gastric ulcer bleeding have advanced with the advent of hemostatic forceps and potassium-competitive acid blocker (P-CAB). Thus, causes and treatments for gastric ulcer bleeding have changed over the last decade.

AIM

To examine the trends of gastric ulcer bleeding over 10 years in the metropolitan area of Japan.

METHODS

This is a single-center retrospective study. A total of 564 patients were enrolled from inpatients admitted to our hospital with gastric ulcer bleeding between 2006 and 2016. Age, medication history, H. pylori infection, method of treatment, rate of rebleeding, and the length of hospitalization were analyzed. Factors associated with gastric ulcer bleeding were evaluated using Fisher's exact test, Pearson's Chi-squared test or Student's t-test as appropriate. The Jonckheere-Terpstra test was used to evaluate trends. A per-protocol analysis was used to examine the rate of H. pylori infection.

RESULTS

There was a significant increase in the mean age over time (P < 0.01). The rate of H. pylori infection tended to decrease over the study period (P = 0.10), whereas the proportion of patients taking antithrombotic agents or NSAIDs tended to increase (P = 0.07). Over time, the use of NSAIDs and antithrombotic drugs increased with age. By contrast, the rate of H. pylori infection during the study period fell with age. H. pylori-induced ulcers accounted for the majority of cases in younger patients (< 70 years old); however, the rate decreased with age (P < 0.01). The method of treatment trend has changed significantly over time. The main method of endoscopic hemostasis has changed from clipping and injection to forceps coagulation (P < 0.01), and frequently prescribed medicines have changed from proton pump inhibitor to P-CAB (P < 0.01). The rate of rebleeding during the latter half of the study was significantly lower than that in the first half.

CONCLUSION

These trends, gastric ulcers caused by ulcerogenic drugs were increasing with age and H. pylori-induced ulcers were more common in younger patients, were observed.

A comparison between dexlansoprazole modified release-based and lansoprazole-based nonbismuth quadruple (concomitant) therapy for first-line Helicobacter pylori eradication: a prospective randomized trial

Purpose

Steadily maintaining high intra-gastric PH is the major factor for successful Helicobacter pylori (H.pylori) eradication. It is important to search for a stronger PPI. Dexlansoprazole MR is a dual delayed release formulation PPI taken once daily which is capable of maintaining longer duration of high intra-gastric PH. It is very effective in treating gastroesophageal disease but reports on H, pylori eradication is very rare. This study sought to compare dexlansoprazole MR-based concomitant treatment and lansoprazole-based concomitant treatment in H. pylori infection and to investigate the factors that affect the eradication rates.

Methods

Two hundred two participants with H. pylori infection were included and randomly assigned to seven days of dexlansoprazole MR-based concomitant therapy (dexlansoprazole MR 60 mg once daily, clarithromycin 500 mg twice daily, amoxicillin 1 g twice daily and metronidazole 500 mg twice daily; DACM group) or a seven days of lansoprazole-based concomitant therapy (lansoprazole 30 mg twice daily, clarithromycin 500 mg twice daily, amoxicillin 1 g twice daily, and metronidazole 500 mg twice daily; LACM group). The participants were asked to perform urea breath tests eight weeks later.

Results

The eradication rates in the DACM group were 86.1% [95% confidence interval (CI): 77.8%–92.2%] in the ITT analysis and 90.6% (95% CI: 82.9%–95.6%) in the PP analysis, respectively, as compared with 90.1% (95% CI: 82.6%–95.2%) and 92.6% (95% CI: 85.5%–96.9%) (p=0.384 and p=0.572, respectively) in the LACM group for the same analyses. The adverse event rates were 11.5% in the DACM group and 10.2% in the LACM group (p=0.779).

Conclusion

As a first-line H. pylori treatment regimen, dexlansoprazole MR-based concomitant therapy attained a successful eradication rate of 90%, which was non inferior to that of lansoprazole-based concomitant treatment.

ClinicalTrials.gov identifier

NCT03829150.

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Optimizing proton pump inhibitors in Helicobacter pylori treatment: Old and new tricks to improve effectiveness

The survival and replication cycle of Helicobacter pylori (H. pylori) is strictly dependant on intragastric pH, since H. pylori enters replicative phase at an almost neutral pH (6-7), while at acid pH (3-6) it turns into its coccoid form, which is resistant to antibiotics. On these bases, it is crucial to increase intragastric pH by proton pump inhibitors (PPIs) when an antibiotic-based eradicating therapy needs to be administered. Therefore, several tricks need to be used to optimize eradication rate of different regimens. The administration of the highest dose as possible of PPI, by doubling or increasing the number of pills/day, has shown to be able to improve therapeutic outcome and has often proposed in rescue therapies, even if specific trials have not been performed. A pre-treatment with PPI before starting antibiotics does not seem to be effective, therefore it is discouraged. However, the choice of PPI molecule could have a certain weight, since second-generation substances (esomeprazole, rabeprazole) are likely more effective than those of first generation (omeprazole, lansoprazole). A possible explanation is due to their metabolism, which has been proven to be less dependent on cytochrome P450 (CYP) 2C19 genetic variables. Finally, vonoprazan, a competitive inhibitor of H+/K+-ATPase present on luminal membrane of gastric parietal cells has shown the highest efficacy, due to both its highest acid inhibition power and rapid pharmacologic effect. However current data come only from Eastern Asia, therefore its strong power needs to be confirmed outside this geographic area in Western countries as well as related to the local different antibiotic resistance rates.