Vitamin-C as anti-Helicobacter pylori agent: More prophylactic than curative- Critical review

Association between dietary antioxidant index and risk of Helicobacter pylori infection among adults: a case-control study

Backgrounds and aims

One of the most important risk factors for Helicobacter pylori (H. pylori) infection is nutrition. Balanced diets with high antioxidant properties may have protective effects against the consequences of this infection. In the current study, we aimed to investigate the association between the dietary antioxidant index and the risk of H. pylori infection among adults.

Methods

In a case–control study the dietary intake of patients with H. pylori infection was compared with healthy subjects. The dietary antioxidant index (DAI) was calculated using dietary intakes derived from a validated food frequency questionnaire (FFQ). Demographic information was obtained by a related questionnaire and Physical Activity was measured by International Physical Activity Questionnaire (IPAQ) were used to obtain information. Using logistic regression models, we evaluated the association between the DAI and H. pylori infection risk. The significance level was determined as P < 0.05.

Results

Finally, dietary data of 148 cases and 302 controls (mean age: 38.72 ± 10.61 (were analyzed. The mean of total DAI was significantly higher in controls (7.67) when compared with H. pylori cases (3.57) (P < 0.001). After adjustment for covariates, participants with less than median DAI values had an increased risk of H. pylori onset (adjusted OR 1.08, 95% CI: 1.02–1.12, P < 0.001).

Conclusions

Appropriate intake of nutrient antioxidants may have a role in decreasing the likelihood of H. pylori infection risk.

Overview of Helicobacter pylori Infection: Clinical Features, Treatment, and Nutritional Aspects

Helicobacter pylori (H. pylori) is a 0.5-1 µm wide, 2-4 µm long, short helical, S-shaped Gram-negative microorganism. It is mostly found in the pyloric region of the stomach and causes chronic gastric infection. It is estimated that these bacteria infect more than half of the world's population. The mode of transmission and infection of H. pylori is still not known exactly, but the faecal-oral and oral-oral routes via water or food consumption are thought to be a very common cause. In the last three decades, research interest has increased regarding the pathogenicity, microbial activity, genetic predisposition, and clinical treatments to understand the severity of gastric atrophy and gastric cancer caused by H. pylori. Studies have suggested a relationship between H. pylori infection and malabsorption of essential micronutrients, and noted that H. pylori infection may affect the prevalence of malnutrition in some risk groups. On the other hand, dietary factors may play a considerably important role in H. pylori infection, and it has been reported that an adequate and balanced diet, especially high fruit and vegetable consumption and low processed salty food consumption, has a protective effect against the outcomes of H. pylori infection. The present review provides an overview of all aspects of H. pylori infection, such as clinical features, treatment, and nutrition.

Vitamin C and Helicobacter pylori Infection: Current Knowledge and Future Prospects

The gram-negative bacterium, Helicobacter pylori (H. pylori), infection is predominantly known for its strong association with development of gastric diseases, including gastritis, peptic ulcers, and stomach cancer. Numerous clinical reports show that ascorbic acid deficiency has been connect with gastritis. Vitamin C levels both in gastric acid and serum have constantly been affirmed to be low in subjects with H. pylori infected gastritis and peptic ulcers. Ascorbic acid supplementation likely relates to reduced incidences of bleeding from peptic ulcers and gastric cancer. H. pylori eradication is shown to increase vitamin C levels, while the benefits of ascorbic acid oral intake to increase the effectiveness of H. pylori-eradication therapy are controversial. Recent studies suggest that ascorbate intake intravenously, but not orally; pharmacologic ascorbate concentrations up to 30 mmol/L in blood, several millimolar in tissues as well as in interstitial fluid, are easily and safely achieved. Pharmacologic ascorbate can exert pro-oxidant effects locally as a drug by mediating hydrogen peroxide (H₂O₂) formation, which was applied to animal and clinical trials of cancer, sepsis, and severe burns etc. In this review, we summarize current understanding of the associations of vitamin C and H. pylori infection, and outline some potential strategies for H. pylori intervention from emerging advances on ascorbic acid physiology and pharmacology.

Vitamin C: A Preventative, Therapeutic Agent Against Helicobacter pylori

The treatment of Helicobacter pylori (H. pylori) induced infections using antibiotic therapies is clinically well accepted; however, using a noninvasive approach with the implementation of therapeutic agents such as vitamin C is not well investigated. Vitamin C has certain characteristics, which allow for it to be considered as a potential treatment option for patients with H. pylori infections. Vitamin C's hostility and mechanism of action towards H. pylori infection in peptic ulcer disease can be classified into two categories: as a preventative agent and alternatively as a therapeutic agent. Preventatively vitamin C acts as a biological antioxidant as well as an immune boosting agent, while therapeutically it acts as an inhibitor of urease, a potential collagen synthesizing agent, and a stimulant in prostaglandin synthesis. As a result, the dosage of vitamin C should be highly regulated. Furthermore, numerous studies have shown that vitamin C supplementation if taken with antibiotics can increase the efficiency of the treatment leading to an increased possibility of eradication of H. pylori in infected individuals. This paper will investigate the recent studies that show different mechanisms through which vitamin C can be used as a preventative or a therapeutic agent for the treatment of H. pylori related infections.

Vitamin C transporter gene (SLC23A1 and SLC23A2) polymorphisms, plasma vitamin C levels, and gastric cancer risk in the EPIC cohort

Vitamin C is known to protect mucosal tissues from oxidative stress and inhibit nitrosamine formation in the stomach. High consumption of fruits, particularly citrus, and higher circulating vitamin C concentrations may be inversely associated with gastric cancer (GC) risk. We investigated 20 polymorphisms in vitamin C transporter genes SCL23A1 and SCL23A2 and GC risk in 365 cases and 1,284 controls nested within the European Prospective Investigation into Cancer and Nutrition cohort. We also evaluated the association between these polymorphisms and baseline plasma vitamin C levels in a subset of participants. Four SNPs were predictors of plasma vitamin C levels (SLC23A1 rs11950646 and rs33972313; SLC23A2 rs6053005 and rs6133175) in multivariable linear regression models. One SNP (SLC23A2 rs6116569) was associated with GC risk, in particular non-cardia GC (OR = 1.63, 95 % CI = 1.11-2.39, based on 178 non-cardia cases), but this association was attenuated when plasma vitamin C was included in the logistic regression model. Haplotype analysis of SLC23A1 yielded no associations with GC. In SLC23A2, one haplotype was associated with both overall and non-cardia GC, another haplotype was associated with GC overall, and a third was associated with intestinal-type GC. Common variants in SLC23A1 and SLC23A2 may influence plasma vitamin C concentration independent of dietary intake, and variation in SLC23A2 may influence GC risk. Additional prospective studies in large populations and consortia are recommended. Investigation of variation in vitamin C transporter genes may shed light on the preventative properties of vitamin C in gastric carcinogenesis.

Evaluation of the benefit of addition of clidinium C to a Helicobacter pylori eradication regimen

AIM

This study aimed to evaluate the success of H.pylori eradication therapy in patients with dyspepsia by therapeutics regimes with and without clidinium C.

BACKGROUND

Helicobacter pylori infections are reported in all parts of the world. Appropriate antibiotic therapy can treat infection. The ideal treatment regimen has not been specified.

PATIENTS AND METHODS

In a randomized, double blind clinical trials study, 250 patients with dyspepsia were enrolled. All patients were treated by Omeprazole, Metronidazole, Amoxicillin and Bismuth (OMAB) for two weeks. One tablet clidinium C before each meal was added to this regimen in the intervention group (A). Urea Breath Test (UBT) was carried out after 8-12 weeks after treatment for evaluation of H.pylori eradication.

RESULTS

132 patients in the intervention group (A) and 118 patients in the control group (B) were enrolled to the study. The rate of eradication in group A was significantly higher than group B (62.1% vs. 50%, p=0.04).

CONCLUSION

The results supported the effect of clidinium C for increasing of helicobacter pylori eradication, but further studies need to be performed.