Relationship between vitamin B12, folate and homocysteine levels and H. pylori infection in patients with functional dyspepsia: A cross-section study

ABSTRACT: BACKGROUND: H. pylori infection has been associated with many micronutrient deficiencies. There is a dearth of data from communities with nutritional deficiencies and high prevalence of H. pylori infection. The aim of this study was to determine the impact of H. pylori infection on serum levels of vitamin B12, folate and homocysteine in patients with functional dyspepsia (FD). METHODS: One hundred and thirty-two patients with FD undergoing gastroscopy were enrolled. The serum was analyzed for B12, folate and homocysteine levels before gastroscopy. H. pylori infection was diagnosed by histopathological examination of gastric biopsies and urea breath test. An independent sample t-test and the Mann-Whitney test were used to compare mean serum concentrations of biomarkers between H. pylori-positive and H. pylori-negative groups of patients. A Chi-square test was performed to assess the differences among proportions, while Spearman's rho was used for correlation analysis between levels of B12 and homocysteine. RESULTS: The mean age of the group was 40.3 +/- 11.5 (19-72) years. Folate deficiency was seen in 43 (34.6%), B12 deficiency in 30 (23.1%) and hyperhomocysteinemia in 60 (46.2%) patients. H. pylori was present in 80 (61.5%) patients with FD while it was absent in 50 (38.5%). Mean serum levels of B12, folate and homocysteine in the H. pylori-positive group of patients were not significantly different from the levels in the H. pylori-negative group (357 +/- 170 vs. 313 +/- 136 pg/mL; p = 0.13), (4.35 +/- 1.89 vs. 4.42 +/- 1.93 ng/mL; p = 0.84); (15.88 +/- 8.97 vs. 16.62 +/- 7.82 mumol/L; p = 0.24); respectively. B12 deficiency ([less than or equal to]200 pg/mL) was 23.8% in the H. pylori-positive patients versus 22.0% in the H. pylori-negative patients. Folate deficiency ([less than or equal to]3.5 ng/mL) was 33.8% in the H. pylori-positive group versus 36% in the H. pylori-negative group. Hyperhomocysteinemia (>15 mumol/L) was present in 46.2% of H. pylori-positive patients compared to 44% in the H. pylori-negative group. Correlation analysis indicated that serum B12 levels were inversely associated with serum levels of homocysteine in patients with FD (rho = 0.192; p = 0.028). CONCLUSIONS: This study demonstrated an inverse relationship between serum levels of B12 and homocysteine in patients with FD. Moreover, no impact of the presence of H. pylori was found on B12, folate and homocysteine levels in such patients.     

Cardiac autonomic function in Blacks with congestive heart failure: vagomimetic action, alteration in sympathovagal balance, and the effect of ACE inhibition on central and peripheral vagal tone.

Cardiac autonomic dysfunction is common in heart disease with or without congestive heart failure, and can cause sudden cardiac death. However, cardiac autonomic abnormalities in non-ischemic (hypertensive) heart failure, which is prevalent in Black Africans is poorly documented. We conducted a cross-sectional study of 32 patients with congestive heart failure, mostly secondary to hypertension (aged 52 +/- 15 years, with ejection fraction of 0.38 +/- 11) and 30 age- and sex-matched healthy volunteers (aged 51 +/- 11 years, 14 males/16 females). Cardiac autonomic function was assessed by the Valsalva's maneuver, respiratory sinus arrhythmia (for cardiac vagal tone) and the pressor and chronotropic changes following forearm isometric handgrip exercise and the assumption of upright posture (tests of sympathetic function). The exercise tolerance of the cardiac patients was assessed by the distance covered during 6 min of walking. The Valsalva ratio was significantly lower in chronic heart failure, 1.10 +/- 0.08 compared to the healthy controls 1.47 +/- 0.20 (p<0.001). Specifically, the phase IV bradycardia in heart failure, was significantly attenuated to 650 +/- 121 msec compared to the value of 935 +/- 101 msec in healthy controls (p<0.001). The phase 11 Valsalva tachycardia did not differ between the patients and controls. The respiratory sinus arrhythmia was also significantly reduced in chronic heart failure (p<0.05) compared to controls. Treatment of the heart failure patients with enalapril-digoxin and diuretics by 4 weeks, resulted in a reversal of the autonomic abnormalities. The phase IV bradycardia increased significantly to 798 +/- 164 msec (p<0.01) and the Valsalva ratio to 1.35 +/- 0.25 (p<0.01) and the respiratory sinus arrhythmia increased toward normal. There was close positive correlation between the Valsalva's ratio and the 6 min self paced distance covered (r = 0.44, p = 0.03 ANOVA), and a weak inverse correlation to cardiac size and cardiothoracic ratio (r = -0.31, p = 0.09). This study demonstrates cardiac autonomic dysfunction (especially reduced vagal tone) in Black Nigerians with mainly non-ischemic congestive heart failure. The parasympathetic dysfunction significantly correlates with severity of heart failure. Current treatment reverses autonomic dysfunction to values seen in healthy age matched controls, mainly through augmentation of cardiac parasympathetic activity.     

Impact of cryoballoon-guided pulmonary vein isolation on non-invasive autonomic tests in patients with paroxysmal atrial fibrillation

BackgroundPulmonary vein isolation (PVI) modulates the intrinsic cardiac autonomic nervous system (ANS). We evaluated the impact of PVI on 5 non-invasive autonomic tests.MethodsThirty patients (76% male, mean age 60.37 ± 9.02 years) with paroxysmal atrial fibrillation (AF) underwent cryoballoon-guided PVI. Five autonomic tests were performed 24hrs before and after PVI (N = 30) and repeated after 6months (N = 22). Parasympathetic function was measured by heart rate (HR) variability during deep breathing (E/I ratio, I-E difference), Valsalva maneuver (Valsalva-ratio) and head-up tilt test (30/15 ratio). Sympathetic function was measured by systolic BP response to sustained handgrip and 10’ tilting and by diastolic BP response to cold water.Results24hrs after PVI, baseline HR increased from 57.93 ± 9.06 bpm to 71.10 ± 12.75 bpm (p < 0.001). At 6 months, baseline HR was lower than immediately post-PVI (62.59 ± 7.89 vs 71.36 ± 13.58 bpm, p = 0.032) but still higher in comparison to pre-PVI (62.59 ± 7.89 vs 57.09 ± 8.80 bpm, p < 0.001). No differences were seen in baseline BP and parasympathetic tests acutely and at 6months. Besides an acute lowering in systolic BP increase during handgrip test, all sympathetic tests remained unchanged.ConclusionsAn acute HR increase attenuated at 6months and an acute lowered systolic BP response to sustained handgrip were the only changes after cryoballoon-guided PVI. Non-invasive autonomic tests seem therefore not appropriate to evaluate the autonomic modulatory effect of PVI, either due to a too limited sensitivity or a too localized effect of PVI to influence test results.     

13C-urea breath test to assess Helicobacter pylori bacterial load

BACKGROUND: Some authors have reported, using different protocols, that 13C-urea breath test (13C-UBT) is capable of assessing the intragastric Helicobacter pylori bacterial load, whereas others have not confirmed these data. Our aim is to evaluate the correlation between 13C-UBT values and H. pylori bacterial load. MATERIALS AND METHODS: One hundred ninety-two patients diagnosed H. pylori-positive by rapid urease test, histology, and 13C-UBT were enrolled. H. pylori bacterial load (H. pylori score) and gastritis activity (activity score) were evaluated according to the Updated Sydney System. 13C-UBT was performed according to the European Standard Protocol. Breath samples were obtained every 10 minutes for 60 minutes in 52 patients and at 30 minutes (T30) in 140 patients and analyzed by mass spectrometry. RESULTS: At T30, mean +/- SD excess delta 13CO2 excretion was 17.4 +/- 1.1, 29.9 +/- 2.2, and 48.7 +/- 4.8 in patients with H. pylori scores 1, 2, and 3, respectively. This difference was statistically significant: H. pylori score 1 versus 2, p < .005; score 1 versus 3, p < .05; score 2 versus 3, p < .05. A significant positive correlation (G = 0.59) was found between H. pylori score and activity score of chronic gastritis. At T40 and T50 significant correlation between mean excess delta 13CO2 excretion and bacterial load was achieved only in patients with H. pylori scores 1 and 3. CONCLUSIONS: 13C-UBT European Standard Protocol values correlate with H. pylori bacterial load and the activity of gastritis at T30 breath sampling time.     

Blunted muscle vasodilatation during chemoreceptor stimulation in patients with heart failure

Chemoreflex control of sympathetic nerve activity is exaggerated in heart failure (HF) patients. However, the vascular implications of the augmented sympathetic activity during chemoreceptor activation in patients with HF are unknown. We tested the hypothesis that the muscle blood flow responses during peripheral and central chemoreflex stimulation would be blunted in patients with HF. Sixteen patients with HF (49 +/- 3 years old, Functional Class II-III, New York Heart Association) and 11 age-paired normal controls were studied. The peripheral chemoreflex control was evaluated by inhalation of 10% O(2) and 90% N(2) for 3 min. The central chemoreflex control was evaluated by inhalation of 7% CO(2) and 93% O(2) for 3 min. Muscle sympathetic nerve activity (MSNA) was directly evaluated by microneurography. Forearm blood flow was evaluated by venous occlusion plethysmography. Baseline MSNA were significantly greater in HF patients (33 +/- 3 vs. 20 +/- 2 bursts/min, P = 0.001). Forearm vascular conductance (FVC) was not different between the groups. During hypoxia, the increase in MSNA was significantly greater in HF patients than in normal controls (9.0 +/- 1.6 vs. 0.8 +/- 2.0 bursts/min, P = 0.001). The increase in FVC was significantly lower in HF patients (0.00 +/- 0.10 vs. 0.76 +/- 0.25 units, P = 0.001). During hypercapnia, MSNA responses were significantly greater in HF patients than in normal controls (13.9 +/- 3.2 vs. 2.1 +/- 1.9 bursts/min, P = 0.001). FVC responses were significantly lower in HF patients (-0.29 +/- 0.10 vs. 0.37 +/- 0.18 units, P = 0.001). In conclusion, muscle vasodilatation during peripheral and central chemoreceptor stimulation is blunted in HF patients. This vascular response seems to be explained, at least in part, by the exaggerated MSNA responses during hypoxia and hypercapnia.     

Prevalence of antiplatelet therapy in patients with diabetes

The aim of the present study was to evaluate, by heart rate variability (HRV) with 24-hours ECG Holter (HRV), the circadian autonomic activity in offspring of type 2 diabetic subjects and the relation with insulin-resistance. METHODS: 50 Caucasian offsprings of type 2 diabetic subjects were divided in two groups: insulin-resistant offsprings (IR) and non insulin-resistant offsprings (NIR). Autonomic nervous activity was studied by HRV. Time domain and spectral analysis (low frequency, LF, and high frequency, HF, provide markers of sympathetic and parasympathetic modulation when assessed in normalized units) were evaluated. RESULTS. Time domain showed a reduction of total SDNN in IR (p < 0.001) and NIR (p 0.047) versus controls. Spectral analysis showed a total and night LF higher in IR and NIR than in control group (all p < 0.001). CONCLUSION. In frequency domain, the analysis of sympathetic (LF) and parasympathetic (HF) component evidenced an association between the offspring of type 2 diabetic subjects and a sympathetic overactivity. A global reduction and alteration of circadian rhythm of autonomic activity are present in offspring of type 2 diabetic patients with and without insulin resistance. The data of our study suggested that an autonomic impairment is associated with the familiarity for type 2 diabetes independently to insulin resistance and that an impairment of autonomic system activity could precede the insulin resistance.     

Effects of Helicobacter pylori eradication on platelet activation and disease recurrence in patients with acute coronary syndromes

BACKGROUND: Platelet activation is consistently observed in animal models of Helicobacter pylori infection and could help to explain the alleged epidemiological association between H. pylori and coronary heart disease. MATERIALS AND METHODS: Ninety-two patients with recent acute coronary syndromes were enrolled. Helicobacter pylori-positive patients were randomized to receive a 7-day course of omeprazole, amoxycillin and metronidazole or placebos. Two months later, H. pylori status was reassessed and baseline parameters, including soluble P-selectin and platelet surface expression of CD62P, CD63 and CD41, were measured again. Patients were followed-up for 1 year or until death or readmission. RESULTS: No baseline differences were observed between H. pylori-positive and -negative cases. Among H. pylori-positive patients, 18 received placebo and 31 received active medication resulting in eradication in 21 cases. No differences were observed in inflammatory parameters or platelet activation markers between patients with persistent or resolved H. pylori infection. However, coronary events recurred at 6 and 12 months, respectively, in 35% and 55% of patients with persisting H. pylori infection compared with 10% and 25% of patients in whom H. pylori was either absent or eradicated (p = .01). Only final H. pylori status [RR 3.07 (95% CI 1.35-98)] and number of coronary risk factors [RR 2.58 (95% CI 1.51-4.41)] were independent predictors of recurrence. CONCLUSIONS: Infection with H. pylori does not induce significant platelet activation in patients treated for coronary disease. Helicobacter pylori-infected patients, however, may have an increased risk of recurrence of coronary events.     

Asymptomatic Helicobacter pylori infection increases asymmetric dimethylarginine levels in healthy subjects

BACKGROUND: Chronic infections have been demonstrated to be early factors of atherosclerosis and cardiovascular diseases, and their relevance increases when they are caused by agents with extremely broad spectrum of disease outcome such as Helicobacter pylori. The consequent endothelial impairment leads to a reduced bioavailability of nitric oxide. Increasing evidences have pointed out that the endogenous inhibitor of nitric oxide synthase, asymmetric dimethylarginine, defined as a risk factor for cardiovascular disease, may increase in infections and plays an important role impairing the vascular functions of the endothelium. Starting from these findings, we aim to investigate whether H. pylori may affect asymmetric dimethylarginine levels. MATERIALS AND METHODS: The study was carried out on a group of 186 subjects (age 46.2 +/- 14.9 years). We evaluated asymmetric dimethylarginine, symmetric dimethylarginine, L-arginine, presence of H. pylori by 13C-urea breath test, and the main parameters of glyco and lipo metabolic balance. RESULTS: Increased levels of asymmetric dimethylarginine were found in H. pylori-positive subjects with respect to H. pylori-negative subjects (0.46 x/ / 1.13 versus 0.42 x/ / 1.23 mol/l, p < .001, respectively). No differences were detected in L-arginine levels between the two groups. Multiple regression analysis performed in H. pylori-positive subjects and H. pylori-negative subjects showed profound differences in the variables related to asymmetric dimethylarginine (R2 = 66.9%, p < .01 versus 34.3%, p < .01, respectively) and symmetric dimethylarginine (R2 = 39.2%, p < .01 versus 20.6%, p = .09, respectively) levels. CONCLUSIONS: Our data clearly demonstrate that H. pylori infection increases asymmetric dimethylarginine levels. Moreover, this infection causes a profound metabolic modification that alters the role of the known determinants of asymmetric dimethylarginine levels. We conclude that H. pylori infection must be taken into account as a cause of increased asymmetric dimethylarginine levels and that the eradication of H. pylori may therefore lead to a decrease in asymmetric dimethylarginine levels, which is a further reason for the reduction of the risk for cardiovascular disease in this large portion of population.     

Elevated homocysteine levels in patients with slow coronary flow: relationship with Helicobacter pylori infection

BACKGROUND AND OBJECTIVE: Elevation of plasma homocysteine (Hcy) level has been implicated in the pathogenesis of slow coronary flow (SCF) as it can severely disturb vascular endothelial function. Helicobacter pylori chronically infect the human stomach and causes malabsorption of vitamin B(12) and folate in food, leading ultimately to an increase in circulating Hcy levels. METHODS: Forty-three patients with angiographically proven SCF (group I) were enrolled in this study; 43 cases with normal coronary flow pattern (group II) served as controls. Fasting plasma levels of Hcy, vitamin B(12), and folate were measured in all subjects. Presence of H. pylori infection was defined as positive 14 C urea breath test. Coronary flow patterns for each major epicardial coronary artery were determined with the Thrombolysis in Myocardial Infarction (TIMI) frame count method. RESULTS: Mean TIMI frame count was 46.3 +/- 8.7 in group I and 24.3 +/- 2.9 in Group II (p = .0001). Vitamin B(12) levels were similar, whereas folate levels were dramatically reduced in group I compared to group II (13.2 +/- 4.3 vs. 17.1 +/- 5.2, p = .0001). Plasma Hcy levels were significantly higher in group I compared to group II (13.4 +/- 5.6 vs. 7.9 +/- 2.5, p = .0001) as was the prevalence of H. pylori infection (90.7% in group I vs. 58.1% in group II, p = .001). Hcy levels were elevated (11.7 +/- 5.3 vs. 7.5 +/- 2.7, p = .0001) and folate levels were reduced (13.9 +/- 4.7 vs. 18.6 +/- 4.9, p = .0001) in patients with H. pylori infection, while vitamin B(12) levels were similar in patients with and without H. pylori infection. Correlation analysis revealed a significant negative correlation between plasma folate and Hcy levels and also between folate levels and mean TIMI frame counts (r = -.33, p = .002 vs. r = -.33, p = .003). Moreover, there was a significant positive correlation between plasma Hcy levels and mean TIMI frame counts (r = .66, p = .0001). In addition, the folate level was the only significant determinant of the variance of Hcy in multiple regression analysis (r = -.21, p = .03). CONCLUSION: Our data showed that plasma folate levels were decreased and plasma Hcy levels were increased in patients with SCF compared to controls. Also, the prevalence of H. pylori infection was increased in patients with SCF. These findings suggest that elevated levels of plasma Hcy, possibly caused by H. pylori infection, and/or a possible disturbance in its metabolism may play a role in the pathogenesis of SCF.     

Immunity markers in patients with Helicobacter pylori infection: effect of eradication

BACKGROUND: Helicobacter pylori is a microorganism able to stimulate a robust inflammatory and systemic immune response. AIM: The aim of our study was to evaluate autoimmune markers in dyspeptic patients positive for H. pylori infection compared to a control group of non-H. pylori-infected subjects. The kinetics of cryoglobulins and autoantibodies was evaluated after treatment of the infection. PATIENTS AND METHODS: Dyspeptic patients with active H. pylori infection and age- and sex-matched healthy H. pylori-negative controls were studied. Markers of immunity were compared, in H. pylori-infected patients before, 6 months and 1 year after the end of therapy. Results were also compared between those with and without successful eradication therapy. RESULTS: Eighty-six individual were entered (43 H. pylori-infected). H. pylori-infected patients had higher levels of IgG and/or IgA and/or IgM (22/43 versus 2/43). Circulating immune complexes and cryoglobulins were detected in patients more often than controls (p < .05 for both). Autoantibodies were observed in 13 patients (30% versus 5% in controls) and antithyroid antibodies in 12 (p < .04 versus controls). Lower levels of C3 and/or C4 complement fractions were observed in infected patients with respect to controls (7/43 versus 1/43; p = .014). After 1 year of follow-up, the markers of autoimmunity dramatically improved in patients eradicated for H. pylori infection compared to those in whom therapy failed. No patient developed a clinical autoimmune disorder. CONCLUSIONS: Additional studies are necessary to ascertain the clinical significance of the modifications of autoimmune markers in patients with H. pylori infection.     

Helicobacter pylori-induced immunological responses in patients with duodenal ulcer and in patients with cardiomyopathies

The interaction between the bacteria and the host is a key factor determining the clinical consequences of H. pylori infection. The immune system plays an important role in either promoting or preventing the disease. The mucosal production of TNF-alpha, IL-6, IL-8 and IL-10 and the CagA status were investigated in H. pylori-positive patients with duodenal ulcer (DU). The concentrations of these cytokines in gastric antral mucosal specimens from patients infected with H. pylori (n = 40) were determined by ELISA and compared with data on mucosal specimens from H. pylori-negative patients (n = 12). The local TNF-alpha, IL-6 and IL-8 concentrations in the antral biopsy samples were significantly higher (p < 0.001) in the patients infected with H. pylori than in the samples from the H. pylori-negative subjects. CagA positivity was demonstrated in 39 (97.5%) of the 40 patients with DU, and in 41 (70.7%) of H. pylori-positive (58 of 100) healthy blood donors. In complementary studies focusing on extragastric disease, it was found that 57% of patients with ischaemic heart disease were seropositive as concerns H. pylori, and 91% of them had antibodies against human heat shock protein 60, too. This study suggests that, besides the bacterial virulence factor, the host response of an increased mucosal production of inflammatory cytokines can be relevant to the gastric pathophysiology in H. pylori-induced DU. At the same time, in ischaemic heart diseases the role of autoimmune processes induced by H. pylori cannot be excluded.     

Sympathetic activation restrains endothelium-mediated muscle vasodilatation in heart failure patients

Although the vasodilatory response during mental stress is blunted in heart failure (HF), the mechanisms underlying this phenomenon are not fully understood. We tested the hypothesis that sympathetic activity limits the endothelium-dependent vasodilatation during mental stress in chronic HF patients. Twenty-one HF patients (age 45 +/- 2 yr, functional classes III and IV, New York Heart Association) and 22 age-matched normal controls (NC; age 42 +/- 2 yr, P = 0.13) were studied at rest and during 4 min of Stroop color-word test with brachial intra-arterial saline, acetylcholine (endothelium dependent), phentolamine (alpha-blocker), and phentolamine plus acetylcholine infusion. Forearm blood flow was measured by venous occlusion plethysmography. Baseline forearm vascular conductance (FVC) was significantly lower in HF patients (2.18 +/- 0.12 vs. 3.66 +/- 0.22 units, P = 0.001). During mental stress with saline, the changes in FVC were significantly blunted in HF patients compared with NC (0.92 +/- 0.20 vs. 2.13 +/- 0.39 units, P = 0.001). In HF, the vasodilatation with acetylcholine was similar to saline control and significantly lower than in NC. In HF patients, phentolamine significantly increased FVC responses (1.16 +/- 0.20 vs. 2.09 +/- 0.29 units, P = 0.001), and the difference between HF patients and NC tended to decrease (2.09 +/- 0.29 vs. 3.61 +/- 0.74 units, P = 0.052). The vasodilatation with phentolamine plus acetylcholine was similar between HF and NC (4.23 +/- 0.73 vs. 4.76 +/- 1.03 units, P = 0.84). In conclusion, sympathetic activation mediates the blunted muscle endothelium-mediated vasodilatation during mental stress in HF patients.     

Correlations between aortic stiffness and parasympathetic autonomic function in healthy volunteers

Cardiovascular autonomic dysfunction and alterations in vascular elasticity are known complications of several disorders, including diabetes mellitus, hypertension, hypercholesterolemia, aging, and chronic kidney disease. The current study was designed to test whether a relationship existed between pulse wave velocity (PWV), augmentation index (AIx), aortic elastic properties, and cardiovascular autonomic function in healthy volunteers. The study comprised 25 healthy volunteers, whose aortic strain, distensibility, and stiffness index were measured by echocardiography, whereas PWV and AIx were evaluated by Arteriograph (TensioMed, Budapest, Hungary) in all cases. Autonomic function was assessed by means of 5 standard cardiovascular reflex tests. We found that heart rate response to deep breathing, as the most reproducible cardiovascular reflex test to characterize parasympathetic function, showed low to moderate correlations with PWV (r = -0.431, p = 0.032), aortic strain (r = 0.594, p = 0.002), distensibility (r = 0.407, p = 0.043), and stiffness index (r = -0.453, p = 0.023). Valsalva ratio and autonomic neuropathy score (ANS) correlated with PWV (r = -0.557, p = 0.004 and r = -0.421, p = 0.036, respectively) and AIx (r = -0.461, p = 0.020 and r = -0.385, p = 0.057, respectively), while ANS correlated with even aortic stiffness index (r = -0.457, p = 0.022). Cardiovascular reflex tests mainly characterizing sympathetic function had no correlation with aortic stiffness parameters (p = NS for all correlations). Correlations exist between parameters characterizing aortic elasticity and parasympathetic autonomic function, as shown by standard cardiovascular reflex tests in healthy volunteers.     

E-cadherin gene promoter hypermethylation in H. pylori-induced enlarged fold gastritis

BACKGROUND: Promoter hypermethylation of E-cadherin plays an important role on gastric carcinogenesis. We have previously reported that the odds ratio for gastric carcinoma and the prevalence of diffuse-type early gastric carcinoma in Helicobacter pylori-induced enlarged fold gastritis increased with increasing fold width. Thus, we examined E-cadherin methylation in gastric mucosa from H. pylori-induced enlarged fold gastritis before and after H. pylori eradication. Moreover, we analyzed the mechanism of H. pylori infection-induced E-cadherin hypermethylation. MATERIALS AND METHODS: Twenty-three H. pylori-positive patients with enlarged folds, 18 H. pylori-positive and seven H. pylori-negative patients without enlarged folds, were involved in the study. E-cadherin promoter methylation was studied using quantitative methylation-specific polymerase chain reaction. We investigated methylation percentage and DNA methyltransferase activity in gastric cancer cell lines treated with EGF, TNFalpha, and MG132. RESULTS: E-cadherin methylation percentage of the gastric antral and body mucosa in H. pylori-positive patients with enlarged folds was much greater than that in both H. pylori-positive and -negative patients without enlarged folds. After H. pylori eradication, the methylation percentage in six patients with enlarged fold gastritis decreased significantly from 15.6 +/- 3.9 to 8.8 +/- 2.2 (p < .05). Moreover, the methylation was induced by TNFalpha, MG132, and EGF treatment, and DNA methyltransferase activity was induced by EGF treatment in MKN-1 cells. CONCLUSIONS: Our findings suggest that the hypermethylation of E-cadherin promoter might be involved in the process of gastric carcinoma through the specialized factors in H. pylori-induced enlarged fold gastritis.     

Helicobacter pylori infection is associated with reduced circulating ghrelin levels independent of body mass index

BACKGROUND: Ghrelin stimulates growth hormone and has orexigenic and adipogenic effects. Plasma ghrelin levels are reduced in obesity and possibly in Helicobacter pylori infection. AIM: To investigate whether there was a relation between H. pylori infection, body mass index (BMI) and serum ghrelin or leptin levels. METHODS: University students undergoing an annual health check-up were invited to participate. H. pylori status was based on the presence of specific IgG H. pylori antibodies in urine. Fasting serum ghrelin, leptin levels, and pepsinogen I and II levels were measured by enzyme immunoassay (EIA). RESULTS: Eight hundred and one students volunteered. There was no significant difference in the height and BMI between those with and without H. pylori infection. The population of ghrelin study consisted of 132 (66 H. pylori-positive and 66 H. pylori-negative) students matched for age, sex, and BMI. The ghrelin level in the H. pylori-positive group was significantly lower (median 55 pmol/l) compared to the H. pylori-negative group (103 pmol/l) (p < .00001). Leptin, triglyceride, total cholesterol, and HDL-cholesterol were not different between the two groups, whereas LDL-cholesterol levels were significantly higher (106 versus 100 mg/dl) (p = .03) in the H. pylori-positive group. Leptin levels correlated with the BMI (r = 0.53) (p < .00001). Among H. pylori-positive subjects, ghrelin correlated only with pepsinogen I levels (r = 0.26, p = .04). CONCLUSIONS: H. pylori infection was associated with a reduction in circulating ghrelin levels independent of sex and BMI.     

Genetic polymorphisms of NOD1 and IL-8, but not polymorphisms of TLR4 genes, are associated with Helicobacter pylori-induced duodenal ulcer and gastritis

BACKGROUND: Intracellular pathogen receptor NOD1 is involved in the epithelial cell sensing Helicobacter pylori, which results in a considerable interleukin (IL)-8 production. The aim of this study was to evaluate the relationship between NOD1 and IL-8 genetic polymorphisms and the development of H. pylori-induced gastritis and duodenal ulcer (DU), as compared with TLR4 polymorphisms. MATERIALS AND METHODS: Eighty-five patients with DU and 135 patients with gastritis were enrolled in the study. Seventy-five serologically H. pylori-positive subjects without gastric or duodenal symptoms served as controls. The G796A (E266K) NOD1 polymorphism was determined by restriction fragment length polymorphism, and the -251 IL-8 polymorphism by amplification refractory mutation system method. The TLR4 (ASP/299/Gly and Thr/399/Ile) gene polymorphisms were examined by melting point analysis. RESULTS: AA homozygote mutant variants of NOD1 were detected in 20% of the H. pylori-positive patients with DU versus 7% of H. pylori-positive patients with gastritis and versus 6% of the H. pylori-positive healthy controls. The IL-8 heterozygote mutant variant was detected with a significantly higher frequency among the DU patients and those with gastritis than among the H. pylori-positive controls. However, no significant correlation concerning the frequency of the TLR4 gene polymorphism could be revealed between any group of patients and the controls. CONCLUSION: E266K CARD4/NOD1, but not the TLR4 gene polymorphism increases the risk of peptic ulceration in H. pylori-positive patients. The -251 IL-8 polymorphism was significantly associated with either gastritis or DU in H. pylori-infected subjects. Host factors including intracellular pathogen receptors and IL-8 production play an important role in H. pylori-induced gastric mucosal damage.     

2-week triple therapy for Helicobacter pylori infection is better than 1-week in clinical practice: a large prospective single-center randomized study

BACKGROUND: Proton pump inhibitor (PPI)-based triple therapies are considered the standard regimens for Helicobacter pylori eradication, but the optimal duration of these regimens is still controversial. The aim of this study was to compare the efficacy of 1-week versus 2-week triple therapies in H. pylori-positive patients. MATERIALS AND METHODS: A total of 486 consecutive H. pylori-positive patients were randomized to receive omeprazole, 20 mg b.i.d., clarithromycin 500 mg b.i.d., and either amoxicillin 1 g b.i.d. or metronidazole 500 mg b.i.d. for 1 or 2 weeks. Upper gastrointestinal endoscopy and histology were performed at entry and 2 months after the end of therapy. H. pylori status was defined according to histology and urea breath test. RESULTS: At intention-to-treat analysis, 2-week therapy with omeprazole, amoxicillin, and clarithromycin achieved a significantly higher eradication rate than 1- or 2-week regimens with metronidazole (70% versus 52%, p = .003, versus 56%, p < .01) and the same therapy for 1-week (70% versus 57%, p = .05). At per-protocol analysis, 2-week therapy with omeprazole, amoxicillin, and clarithromycin showed a significantly higher eradication rate than 1-week of amoxicillin and metronidazole (77% versus 62%; p = .03) but no difference with 1-week same regimen (66%) or 2-week metronidazole and clarithromycin regimen (72%). Compliance and tolerability were good for all regimens. CONCLUSIONS: Two-week therapies, independently of antibiotic combination, lead to a significant increase of H. pylori eradication rate compared to 1-week therapies, with same compliance and tolerability, even if, taking account of low-eradication rates, one must question whether the triple therapy should still be used.     

Unawareness of hypoglycaemia and inadequate hypoglycaemic counterregulation: no causal relation with diabetic autonomic neuropathy.

OBJECTIVE--To examine the traditional view that unawareness of hypoglycaemia and inadequate hypoglycaemic counterregulation in insulin dependent diabetes mellitus are manifestations of autonomic neuropathy. DESIGN--Perspective assessment of unawareness of hypoglycaemia and detailed assessment of autonomic neuropathy in patients with insulin dependent diabetes according to the adequacy of their hypoglycaemic counterregulation. SETTING--One routine diabetic unit in a university teaching hospital. PATIENTS--23 Patients aged 21-52 with insulin dependent diabetes mellitus (seven with symptoms suggesting autonomic neuropathy, nine with a serious clinical problem with hypoglycaemia, and seven without symptoms of autonomic neuropathy and without problems with hypoglycaemia) and 10 controls with a similar age distribution, without a personal or family history of diabetes. MAIN OUTCOME MEASURES--Presence of autonomic neuropathy as assessed with a test of the longest sympathetic fibres (acetylcholine sweatspot test), a pupil test, and a battery of seven cardiovascular autonomic function tests; adequacy of hypoglycaemic glucose counterregulation during a 40 mU/kg/h insulin infusion test; history of unawareness of hypoglycaemia; and response of plasma pancreatic polypeptide during hypoglycaemia, which depends on an intact and responding autonomic innervation of the pancreas. RESULTS--There was little evidence of autonomic neuropathy in either the 12 diabetic patients with a history of unawareness of hypoglycaemia or the seven patients with inadequate hypoglycaemic counterregulation. By contrast, in all seven patients with clear evidence of autonomic neuropathy there was no history of unawareness of hypoglycaemia and in six out of seven there was adequate hypoglycaemic counterregulation. Unawareness of hypoglycaemia and inadequate hypoglycaemic counterregulation were significantly associated (p less than 0.01). The response of plasma pancreatic polypeptide in the diabetic patients with adequate counterregulation but without autonomic neuropathy was not significantly different from that of the controls (change in plasma pancreatic polypeptide 226.8 v 414 pmol/l). The patients with autonomic neuropathy had a negligible plasma pancreatic polypeptide response (3.7 pmol/l), but this response was also blunted in the patients with inadequate hypoglycaemic counterregulation (72.4 pmol/l) compared with that of the controls (p less than 0.05). CONCLUSIONS--Unawareness of hypoglycaemia and inadequate glucose counterregulation during hypoglycaemia are related to each other but are not due to autonomic neuropathy. The blunted plasma pancreatic polypeptide responses of the patients with inadequate hypoglycaemic counterregulation may reflect diminished autonomic activity consequent upon reduced responsiveness of a central glucoregulatory centre, rather than classical autonomic neuropathy.     

Helicobacter pylori infection in patients with Hepatitis C Virus positive chronic liver diseases

BACKGROUND AND GOALS: One-third of patients with liver cirrhosis suffers from acute peptic ulcer, a disease strongly correlated with Helicobacter pylori (H. pylori) infection. We report the seroprevalence of antibodies to H. pylori in 179 patients with Hepatitis C Virus (HCV)-related chronic active hepatitis and cirrhosis. MATERIALS AND METHODS: Among patients, 135 (86 males and 49 females, mean age 51.2 +/- 13.28, range 27-77 years) had chronic active hepatitis (CAH) and 44 cirrhosis (28 males and 16 females, mean age 62.4 +/- 9.2, range 37-77 years). Serum antibodies to H. pylori were tested using a commercial enzyme immunosorbent assay. The control population consisted of 619 consecutive blood donors (523 males, 96 females, mean age 47 +/- 5.3 years, range 18-65). RESULTS: The overall prevalence of antibodies to H. pylori was 73.1% (131/179) among patients and 47% (291/619) among blood donors (p<0.0001; OR 3.08 [95%CI, 2.10-4.51]). 70.5% (24/34) of patients aged less than 40 years were seropositive for H. pylori versus 34.2% (90/263) of controls (p<0.0001; OR 4.61[95%CI, 2.0-10.85]). Among cirrhosis patients, the prevalence of antibodies to H. pylori was 79.5% (35/44) versus 47% (291/619) of controls (p<0.0001; OR 4.38 [95%CI, 1.98-9.98]). Overall seroprevalence among CAH patients was 71.1% (96/135) versus 47% (291/619) of blood donors (p<0.0001; OR 2.77 [95%CI, 1.82-4.24]). CONCLUSIONS: The high seroprevalence of antibodies to H. pylori in patients with HCV-positive liver diseases explains the elevated incidence of peptic ulcer, and warrants studies on the pathogenic role in human liver diseases of Helicobacter spp which is known to cause chronic hepatitis and hepatocellular carcinoma in mice.     

Local and peripheral cytokine response and CagA status of Helicobacter pylori-positive patients with duodenal ulcer

The mucosal production of TNF-alpha, IL-6, IL-8, IL-10 and nitrotyrosine was investigated in H. pylori-positive patients with duodenal ulcer (DU). The concentrations of these cytokines in gastric antrum mucosal specimens from patients infected with H. pylori (n = 40) were determined by ELISA and compared with data on mucosal specimens from H. pylori-negative patients (n = 12). Nitrotyrosine was determined by ECL Western blotting. It was additionally investigated whether the tissue levels of the cytokines correlated with the peripheral cytokine levels, and the CagA status of the patients. The local TNF-a, IL-6 and IL-8 concentrations in the antral biopsy samples were significantly higher (p < 0.001) in the patients infected with H. pylori than in the samples from the H. pylori-negative subjects. There was a negative correlation between the TNF-alpha and IL-10 concentrations. Further more, in 23 of the 40 biopsy specimens, considerable nitrotyrosine production was detected by ECL Western blotting. There was no significant difference in peripheral TNF-a and IL-6 production between the DU patients and healthy blood donors (n = 100; 58% of whom were also H. pylori-positive). Only the in vitro IL-8-producing capacity was higher in the peripheral blood of the DU group after ex vivo induction with H. pylori. CagA positivity was demonstrated in 39 (97.5%) of the 40 patients with DU, and in 41 (70.7%) of the 58 H. pylori-positive, healthy blood donors. This study suggests that besides the bacterial virulence factor, the host response, with an increased mucosal production of inflammatory cytokines and reactive oxygen and nitrogen species could be relevant to the gastric pathophysiology in H. pylori-induced DU. There is no generalized cytokine overproduction in these DU patients, but the moderate increase in in vitro IL-8 production might be of pathophysiological importance.