Prevalence of cytotoxin-associated genes of Helicobacter pylori among Iranian GERD patients.

AIM: Since the impact of H. pylori and its virulence is not clear in GERD, this study aimed to evaluate the prevalence of cag A and cag E gens of H. pylori among Iranian GERD patients. BACKGROUND: Gastroesophageal reflux disease (GERD) is defined as a condition of reflux the stomach juice by low pH causes tissue damage. Helicobacter pylori may or may not influence the GERD; however, it is unclear. METHODS: This study was a case-control study performed on patients with GERD who underwent upper gastrointestinal endoscopy at Taleghani Hospital of Tehran, Iran. Prevalence of H. pylori and presence of the cag A and cag E genes in GERD and control group was investigated. RESULTS: H. pylori was detected in 54% and 62% of GERD and control groups respectively. Prevalence of cag A gene among GERD patients was 44.4% whereas among the control group it was 87%. Prevalence of the cag E among GERD patients and control group was 44.4% and 64% respectively. Coexistence of cag A and cag E in GERD patients was 25.7% and in the control patients it was 54.8%. CONCLUSION: We did not find correlation between H. pylori existence in GERD patients in comparison to the control group. Similar to other Asian studies, the presence of the cag A in control group was more than GERD patients significantly. The co-existence of cag A and cag E was also more in control group significantly.

Pathological and Clinical Correlation between Celiac Disease and Helicobacter Pylori Infection; a Review of Controversial Reports.

There are overwhelming reports and descriptions about celiac associated disorders. Although there is a clear genetic association between celiac disease (CD) and some gastrointestinal disorders, there are controversial reports claiming an association between CD and Helicobacter pylori (H. pylori) infection. Different studies indicated the possible association between lymphocytic gastritis and both CD and H. pylori infection, although this evidence is not consistently accepted. Also it was shown that an increase in intraepithelial lymphocytes count is associated with both H. pylori infection and celiac disease. Therefore the following questions may raise: how far is this infection actually related to CD?, which are the underlying patho-mechanisms for these associations? what are the clinical implications? what is the management? and what would be the role of gluten free diet in treating these conditions? PubMed (PubMed Central), Ovid, ISI of web knowledge, and Google scholar were searched for full text articles published between 1985 and 2015. The associated keywords were used, and papers described particularly the impact of pathological and clinical correlation between CD and H. pylori infection were identified. In this review we tried to answer the above questions and discussed some of the recent developments in the pathological and clinical aspects of CD and H. pylori infection.

Correlation between global genome methylation and mutation at CpG codons of p53 gene.

OBJECTIVE: Hypomethylation within the body of the p53 gene, which is normally methylated, has been found in neoplasms. Also, the CG → TA transition was not detected in the CpG codons of the p53 gene in gastritis lesions in Iranian patients. Therefore, an evaluation of the probable correlation between global genome methylation and alteration at CpG codons of p53 gene was needed. METHODS: For defining the genotypes of CpG codons, DNA sequencing was performed on 90 paired samples of gastritis and normal tissues. To measure global genome methylation status, the extracted DNA was digested with HpaII (methylation sensitive) and MspI (insensitive). Then, enzymatic digestion was quantitated using Pyrosequencing as peak height. By calculating the HpaII/ MspI peak ratio it is possible to evaluate the methylation level of normal and gastritis tissues. RESULTS: Codons 9, 245 and 248 underwent a CG → AT transversion but not a CG → TA transition. In addition, the mean methylation level was significantly different between the patients with GG and GT genotypes at codon 245 (P = 0.019). CONCLUSIONS: As CG → AT transversion at codon 245 is associated with global genome methylation, GG hypomethylation may induce different pattern of mutations, for example, C → A instead of C → T at the CpG codons of the p53 gene during gastritis development in Iranian patients.

The effect of the treatment of Helicobacter pylori infection on the glycemic control in type 2 diabetes mellitus.

AIM: To evaluate the possible long-term effects of Helicobacter pylori infection on Hemoglobin A1c and fasting blood sugar levels in patients with type 2 diabetes. BACKGROUND: Helicobacter pylori causes the gastrointestinal tract inflammation, which it plays an important role in distortion of glucose and lipids absorption that altered lipid metabolism and energy harvesting and develops type 2 diabetes, insulin resistance and has been linked to impaired blood glucose. PATIENTS AND METHODS: In this clinical trial, patients with type 2 diabetes and confirmed Helicobacter pylori infection were recruited from the endocrinology clinic of the Shahid Beheshti University Tehran, Iran. Before and after 3 months of eradication therapy fasting blood samples were taken and glycalated hemoglobin levels and fasting blood sugar levels were measured. RESULTS: 85 (27 male 31.8%, 58 female 68.2%) patients with the mean age of 52.±4.7 years were recruited. 52 (62%) had successful Helicobacter pylori eradication (16 male, 30.8% and 36 female, 69.2%). The mean glycalated haemoglobin levels before successful treatment was 8.7±1.1 and after treatment was 8.3±0.9 and difference was significant (p<0.001). Mean IgG level of serology was 3.3±1.1 and the correlation with glycalated haemoglobin was significant (p=0.02) (r=0.4). CONCLUSION: Our results indicate that the Helicobacter pylori treatment can improve the mean glycalated haemoglobin in patients with type 2 diabetes. More investigations will be required to evaluate the effects of Helicobacter pylori eradication among different age groups and in relation to obesity status, diabetes and other disease, and it may be beneficial for patients at risk of diabetes to be checked for the presence of Helicobacter pylori infection.

Profile and frequency of p53 gene alterations in gastritis lesions from Iran.

BACKGROUND: It has been frequently shown that p53 alterations have an important role in the development of gastric cancers but there is no data on p53 alteration in gastric cancer and its precancerous lesions from Iran although this country experiences one of the highest gastric cancer incidence and mortality rates in the world. The purpose of this study was to do a comprehensive assessment of p53 alterations in the Iranian population of gastritis patients and to evaluate the association between p53 alterations, microsatellite status and clinicopathological aspects. METHODS: After DNA extraction, PCR sequencing was done for exons 2-7. Also microsatellite status was evaluated using five microsatellite markers: NR-27, NR-21, NR-24, BAT-25 and BAT-26. RESULTS: The highest rate of alteration was seen in codons 72 (85.6%, SNP) and 248 (30.9%, mutation). Also, we found 2 new mutations in codons 9 and 146. In contrast with previous work, transition at the CpG codons was relatively rare. Nucleotide alterations were more prevalent in the Helicobacter pylori-positive group but not significantly. Neither nuclear staining for p53 protein nor microsatellite instability was seen in gastritis lesions. CONCLUSION: p53 alterations might contribute to the pathogenesis of gastritis and perhaps gastric cancer in Iran. However, the different spectrum seen here implies other mechanism(s) in gastritis and gastric cancer development in the Iranian population.

Analysis of Helicobacter pylori genotypes in Afghani and Iranian isolates.

The geographical variation in Helicobacter pylori genotypes is an observed phenomenon. Cytotoxin associated genes A (cagA) and E (cagE), and vacuolating cytotoxin (vacA) genotypes of H. pylori are associated with peptic ulcer disease (PUD). This study compared the distribution of these genotypes in Iranian and Afghani isolates and their association with clinical outcomes. H. pylori infected patients, as proven by positive culture, were recruited prospectively. A total of 70 patients, 55 Iranian (26 men and 29 women, mean age 48 +/- 18 years) and 15 Afghani immigrants (13 men and 2 women, mean age 34.8 +/- 11 years) living in Tehran, Iran were enrolled in this study. DNA was extracted from isolated H. pylori and polymerase chain reaction was carried out to determine the cagA and cagE status and vacA alleles. The number of gastric cancer, peptic ulcer and gastritis cases was 11, 23 and 36, respectively. The cagA positive isolates were more common in Iranian (67%) than Afghani isolates (60%). cagE was positive in 53% of Afghani compared to 51% of Iranian isolates. The most common vacA s-region genotype was s1; 80% in Afghani and 67% in Iranian. The slml was a frequently observed genotype in Afghani strains (53%) while s1m2 (47%) was more common in strains isolated from Iranian patients. There is a difference in the H. pylori strains between Iranian and Afghani groups, for instance Iranian isolates were similar to European isolates while Afghani isolates were similar to isolates from India. However, there was no significant association between cagA, cagE and vacA genotypes and clinical outcomes in Iranian and Afghani patients.

Analysis of 3'-end variable region of the cagA gene in Helicobacter pylori isolated from Iranian population.

BACKGROUND AND AIMS: The 3' region of the cagA gene, the most well-known virulence factor of Helicobacter pylori, contains Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs. Four segments flanking the EPIYA motifs, EPIYA-A, -B, -C, or -D, were reported to play important roles in H. pylori-related gastroduodenal pathogenesis. The aim was to determine the roles of EPIYA segments in gastroduodenal pathogenesis in an Iranian population. METHODS: A total of 92 cagA-positive Iranian strains isolated from dyspepsia patients with non-ulcer dyspepsia (n = 77), peptic ulcer (n = 11) and gastric cancer (n = 4) were studied. The EPIYA motif genotyping was determined by polymerase chain reaction and sequencing. RESULTS: A total of 86 (93.5%) strains had three copies of EPIYA (ABC type), three (3.3%) had four copies (ABCC type) and three (3.3%) had two copies (AB type). The alignment of the deduced protein sequences confirmed that there were no East Asian type EPIYA-D sequences (EPIYATIDFDEANQAG) in Iranian strains. When the prevalence of strains with multiple EPIYA-C segments in Iran was compared with previously published data, it was much lower than that in Colombia and Italy, but was higher than that of Iraq, and the patterns were parallel to the incidence of gastric cancer in these countries. CONCLUSION: The structure of the 3' region of the cagA gene in Iranian strains was Western type. Although we could not find differences between EPIYA types and clinical outcomes, low prevalence of strains with multiple EPIYA-C segments might be reasons for low incidence of gastric cancer in Iran.

Evaluation of global genome methylation in gastritis lesion and its correlation with clinicopatological findings.

Global genome hypomethylation as an epigenetic phenomenon may induce (pre)neoplastic transformation through inducing chromosomal and genomic instability and activating oncogenes. Global genome hypomethylation has a fundamental role in early stages of tumorigenesis but little is known about this epigenetic event in gastric precancerous lesions such as gastritis. Therefore, we decided to evaluate this issue in gastritis lesion for obtaining new insight toward molecular biology of gastric cancer. Here we used a technique composed of restriction enzyme digestion and pyrosequencing known as luminometric methylation assay to evaluate this issue. DNA obtained from normal and gastritis lesions was digested with HpaII (sensitive to methylation in its cut site) and MspI (insensitive). Overhangs resulting from these enzymes then fill in by polymerase extension assay using pyrosequencing instrument. Nucleotide incorporation during polymerase extension generates light, which expresses as pick in the pyrogram. By comparing the height of picks obtained form both enzymes it can be possible to evaluate and compare global genome methylation level of gastritis and normal tissues. If the target site is fully methylated, the HpaII/MspI (their pick height) will approach zero. If not, this ratio will be around 1. In the other conditions this ratio varies between 0 and 1. Comparing the ratio of normal and gastritis sample, it can be inferred whether or not gastritis is hypomethylated. This study was performed on 83 gastritis and normal adjacent tissues. The patients included 34 male and 49 female and were 15 to 83 years old. According to our study, gastritis tissue was hypomethylated more than the normal tissue (p = 0.028). Global genome methylation has no significant correlation with MSI, pathological findings, age, and gender. We conclude that global genome hypomethylation occurs in the gastritis level. This reduction probably continues in the next steps toward gastric cancer and may induce other epigenetic and/or genetic changes (such as MSI) that promote carcinogenesis.

Effect of addition of vitamin C to clarithromycin-amoxicillin-omeprazol triple regimen on Helicobacter pylori eradication.

BACKGROUND: The use of vitamin C as a supplement with the common regimen for eradication of Helicobacter pylori infection is the subject of ongoing controversy. We conducted a prospective controlled study with the aim of testing whether the vitamin C supplement to the therapy includes lower dosage of clarithromycin could have an acceptable influence on Helicobacter pylori eradication in comparison with routine anti-Helicobacter pylori regimen. MATERIALS AND METHODS: Two hundred and fourteen consecutive patients with the verification of Helicobacter pylori infection via positive Rapid Urease Test (RUT) and histology results were included and divided into two therapy groups: 1) a group without vitamin C (n = 100) that were administered 20 mg omeprazol, 1 g amoxicillin, and 500 mg clarithromycin twice daily for 2 weeks and 2) a triple-plus-vitamin C group (n = 114) that was administered 20 mg omeprazol, 1 g amoxicillin, 250 mg clarithromycin plus 250 mg vitamin C twice daily for 2 weeks. Four weeks after the completion of therapy, each patient was scheduled for urea breath test to assess the success of Helicobacter pylori eradication. RESULTS: Similar eradication of Helicobacter pylori was found between the triple-only group with 500 mg of clarithromycin and the triple with 250 mg of clarithromycin-plus vitamin C group (89% versus 86.8%, P = 0.623). CONCLUSIONS: Adding vitamin C might reduce the needed dosage of clarithromycin for eradication of Helicobacter pylori.

vacA genotypes of Helicobacter pylori in relation to cagA status and clinical outcomes in Iranian populations.

Mosaicism in vacA alleles with two distinct families of vacA signal sequences (s1 and s2) and two distinct families of middle region alleles (m1 and m2) has been reported. Research suggests that the vacA s1 genotype is closely associated with duodenal ulcer disease and with high cytotoxin production. The aims of this study were to evaluate the role of vacA genotyping with respect to gastric inflammation and injury, and clinical presentation in Iranian populations. Genomic DNA of biopsy specimens from patients with gastritis, peptic ulcer disease (PUD), or gastric cancer (GC) were characterized based on ureC (glmM), cagA, and vacA genotyping by using polymerase chain reaction. Of 167 patients including 33 with PUDs, 129 with non-ulcer dyspepsia (NUD), and 5 with GC, 96 (57.5%) cases were infected by Helicobacter pylori. Among these patients, H. pylori were isolated from 19 (57.7%) PUD patients, 74 (68.7%) NUD patients, and 3 (60%) GC patients. The cagA was detected in 76% of H. pylori-positive cases. The vacA s1-m2 genotype was the most prevalent in 7/19 PUD (37%) and 30/74 NUD (40.5%) patients with H. pylori infection. The prevalence of vacA s2-m1 (8%) was high in Iranian isolates. A significant association was not found between H. pylori genotypes and clinical outcomes. The vacA genotypes and cagA status were not useful markers for gastroduodenal diseases in Tehran, Iran.