Impact of Helicobacter pylori infection on gastric and plasma ghrelin dynamics in humans

Remnant gastritis in gastric cancer patients causes loss of muscle mass 6 months after gastrectomy: a retrospective cohort study of Helicobacter pylori infection

PURPOSE

In this study, we assessed the relationship between remnant gastritis and muscle mass loss and then investigated the potential relationship between Helicobacter pylori (HP) infection and remnant gastritis and muscle loss.

METHODS

We reviewed the medical records of 463 patients who underwent distal gastrectomy between January 2017 and March 2020. Of these patients, 100 with pStage I after laparoscopic surgery were included in this analysis.

RESULTS

A multivariate analysis showed that the total Residue, Gastritis, Bile (RGB) classification score, which indicates the degree of gastritis, was significantly associated with the rate of change (rate of decrease) in the psoas muscle area (PMA) during the first 6 months after surgery (p = 0.014). Propensity score matching was performed according to HP infection, and the rate of change in the PMA and the degree of remnant gastritis in 56 patients were compared. Neither was significantly associated with HP infection.

CONCLUSIONS

Remnant gastritis did contribute to psoas muscle mass loss during the initial 6 months after gastrectomy, and HP infection was not significantly associated with either remnant gastritis or psoas muscle mass loss. Nevertheless, the potential for HP eradication to prevent muscle loss and improve the survival prognosis for gastrectomy patients merits further research.

Circulating ghrelin levels in patients with gastric cancer: a systematic review and meta-analysis

Background

Ghrelin plays a critical role in regulating energy metabolism and homeostasis. The association between circulating ghrelin levels and gastric cancer has not been systematically analyzed.

Objective

This work explored the association between circulating ghrelin levels and gastric cancer.

Methods

The literature search for relevant articles published until November 2022 was performed using PubMed, Cochrane Library, EMBASE, and Web of Science with the keywords "ghrelin" and "gastric cancer". Standardized mean differences (SMD) with 95% confidence intervals were used to measure the effectiveness. We assessed pooled data by use of a random-effects model.

Results

Of 5,302 identified studies, nine were included (N=3,196 participants). Circulating ghrelin levels were lower in gastric cancer patients (SMD=-0.255, 95%CI: -0.528 to 0.017, P < 0.00001), but with high heterogeneity (I2 = 88.8%).

Conclusion

The circulating ghrelin levels in patients with gastric cancer were lower than in controls. However, there was heterogeneity among results; therefore, studies with larger sample sizes are recommended.

Nigella sativa powder for helicobacter pylori infected patients: a randomized, double-blinded, placebo-controlled clinical trial

OBJECTIVE

This double-blind, placebo-controlled, clinical trial was conducted to define the effects of Nigella sativa (N. Sativa) powder plus conventional medical treatment of Helicobacter pylori (H. pylori) on serum ghrelin level and appetite in H. pylori-infected patients.

METHODS

In the present study, 51 H. pylori-positive patients were randomly allocated to treatment (n = 26) or placebo (n = 25) groups. They received 2 g/day N. Sativa with quadruple therapy or 2 g/day placebo plus quadruple therapy for 8 weeks. The serum level of ghrelin was assessed before and after the intervention. Appetite was evaluated at the onset and at the end of the intervention.

RESULTS

At the end of the study, the appetite of the treatment group improved significantly compared with the placebo group (P = 0.02). Statistically, the difference in serum ghrelin levels between the study's groups was insignificant (P > 0.05).

CONCLUSION

Supplementation with N. Sativa powder may be a beneficial adjunctive therapy in H. pylori-infected patients.

TRIAL REGISTRATION

This study was registered in the Iranian Registry of Clinical Trials (IRCT20170916036204N7) on 08/08/2018.

Movement Disorders and the Gut: A Review

There is a close link between multiple movement disorders and gastrointestinal dysfunction. Gastrointestinal symptoms may precede the development of the neurologic syndrome or may arise following the neurologic presentation. This review will provide an overview of gastrointestinal accompaniments to several well-known as well as lesser known movement disorders. It will also highlight several disorders which may not be considered primary movement disorders but have an overlapping presentation of both gastrointestinal and movement abnormalities.

Helicobacter pylori Eradication Therapy Affect the Gut Microbiota and Ghrelin Levels

Background: Antibiotic therapy used to eradicate Helicobacter pylori has been associated with changes in plasma ghrelin and alterations in the gut microbiota. On the other hand, changes in ghrelin levels have been related to changes in gut microbiota composition. Our aim was to evaluate the relationship between changes in the gut microbiota and ghrelin levels in H. pylori infected patients who received antibiotic treatment for its eradication.

Methods: A prospective case-control study that included forty H. pylori-positive patients who received eradication therapy (omeprazole, clarithromycin, and amoxicillin) and twenty healthy H. pylori antigen-negative participants. Patients were evaluated, including clinical, anthropometric and dietary variables, before and 2 months after treatment. Gut microbiota composition was analyzed through 16S rRNA amplicon sequencing (IlluminaMiSeq).

Results: Changes in gut microbiota profiles and decrease in ghrelin levels were identified after H. pylori eradication treatment. Gut bacteria such as Bifidobacterium longum, Bacteroides, Prevotella, Parabacteroides distasonis, and RS045 have been linked to ghrelin levels fasting and/or post meals. Changes in the abundance of Lachnospiraceae, its genus Blautia, as well as Prevotella stercorea, and Megasphaera have been inversely associated with changes in ghrelin after eradication treatment.

Conclusions: Eradication treatment for H. pylori produces changes in the composition of the intestinal microbiota and ghrelin levels. The imbalance between lactate producers such as Blautia, and lactate consumers such as Megasphaera, Lachnospiraceae, or Prevotella, could trigger changes related to ghrelin levels under the alteration of the eradication therapy used for H. pylori. In addition, acetate producing bacteria such as B. longum, Bacteroides, and P. distasonis could also play an important role in ghrelin regulation.

Chronic stress accelerates the process of gastric precancerous lesions in rats

Background: Gastrointestinal cancers account for 20% of all deaths worldwide. Gastric cancer (GC) patients are susceptible to psychological change, especially depression which is commonly induced by chronic stress. Gastric precancerous lesions (GPL) is an important prodromal stage in the occurrence of gastric cancer. Chronic stress influences the prognosis of GC and may influence the process of GPL as well. Methods: Sixty SD rats were randomly divided into a control group, GPL group, and GPL+CUMS group. In the GPL group, 200μg/mL N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) free drinking method combined with intermittent fasting was applied to establish the GPL animal model. Based on this, we combined the GPL rats with chronic unpredicted mild stress (CUMS) to establish a comprehensive model. We then evaluated their behavior by open field tests and sucrose preference tests. We tested the IL-6, IL-10, TNF-α, Ghrelin, Leptin and Somatostatin (SS) levels in serum and observed the expression of Ghrelin and Gastrokine 2(GKN2) in the gastric mucosa of rats with tumors by immunofluorescence. Results: Our results showed that GPL and GPL+CUMS rats all displayed a significantly decreased total distance and mean velocity traveled in the open field test. The percentages of sucrose preference were significantly decreased in the GPL+CUMS group compared to the control group. In addition, IL-6 and TNF-α were significantly increased in both the GPL and GPL+CUMS groups. Furthermore, the GPL+CUMS group showed significantly increased TNF-α levels in serum compared to the GPL rats. Our results showed that the expression of NF-κB, p53, and BCL-2 were significantly increased while BAX was reduced in the GPL and GPL+CUMS groups. Moreover, Ghrelin and Leptin levels in serum were significantly decreased in the GPL and GPL+CUMS groups. SS levels in serum were significantly increased in the GPL+CUMS group. Additionally, we found that the GPL+CUMS rats with tumors not only had strong expression of GKN2 on the luminal side and the lamina propria of the gastric mucosa and tumor, but also had expression of Ghrelin on the luminal side of the gastric mucosa. The areas that showed strong expression of GKN2 and Ghrelin, are all located around the blood vessels in the tumor. Conclusions: GPL rats under chronic stress would aggravate the conditions of GPL, shorten the process of GPL, and increase the risk of tumorigenesis. In addition, the close monitoring of the mental health of cancer survivors and precancerous lesion patients is suggested to be of great significance in the prevention and treatment of cancer.

Assessing the Relationship between Helicobacter pylori and Chronic Kidney Disease

The relationship between Helicobacter pylori infection and/or gastric disorders and chronic kidney disease (CKD) has not been elucidated. We investigated the relationship between Helicobacter pylori and/or atrophic gastritis (AG) and chronic kidney disease. In total, 3560 participants (1127 men and 2433 women) were eligible for this cross-sectional study. We divided participants into four study groups: with/without Helicobacter pylori infection and with/without AG. The HP (+) AG (−) group demonstrated a significant association with CKD compared with the HP (−) AG (−) group (adjusted odds ratio, 1.443; 95% confidence interval, 1.047–1.989). In contrast, the HP (+) AG (+) group showed significantly lower adjusted odds of CKD than the HP (−) AG (−) group (adjusted odds ratio, 0.608; 95% confidence interval, 0.402–0.920). H. pylori infection without AG might be associated with CKD in these participants. Conversely, the HP (+) AG (+) group had lower odds of CKD. Uncovering an association between gastric and renal conditions could lead to development of new treatment strategies.

Relationship between Helicobacter pylori infection and obesity in Chinese adults: A systematic review with meta-analysis

BACKGROUND

Obesity is highly prevalent worldwide. More and more studies have been conducted on the relationship between H. pylori infection and obesity or overweight. But the relationship between them is controversial in the literatures and there is no comprehensive evidence for the correlation.

AIM

To evaluate the prevalence of H. pylori infection in Chinese adult subjects who received routine physical examinations and the relationship between H. pylori and obesity.

METHODS

Literatures on H. pylori infection and obesity in Chinese population were searched in online databases. Relevant data were extracted independently by two researchers and meta-analysis was performed by using Review manager 5.3 software.

RESULTS

22 articles were selected with a total sample size of 178033. The pooled prevalence of H. pylori was 42% (95%CI: 37% to 47%) and mean difference of BMI between subjects with and without H. pylori infection was 0.94 (95%CI: -0.04 to 1.91). 9 eligible studies with 27111 subjects were used to calculated pooled OR value because they contained obesity groups. The OR value showed that H. pylori-positive subjects tended to be obese at a risk of 1.20 (95% CI: 1.13 to 1.28).

CONCLUSION

In China, obesity has association with H. pylori infection. H. pylori infection may be one of the risk factors for obesity.

Serum ghrelin and esophageal and gastric cancer in two cohorts in China

Ghrelin is a hormone produced in the oxyntic glands of the stomach. Previous work by our group has suggested that serum ghrelin concentrations are inversely associated with gastric and esophageal cancer risk. We measured ghrelin concentrations in the Linxian General Population Nutrition Intervention Trial (NIT), and the Shanghai Women's Health Study (SWHS). In NIT, we analyzed serum samples from 298 esophageal squamous cell carcinoma (ESCC) cases, 518 gastric cardia adenocarcinoma (GCA) cases, 258 gastric noncardia adenocarcinoma (GNCA) cases and 770 subcohort controls (case-cohort). In SWHS, we measured ghrelin in plasma samples from 249 GNCA cases and 498 matched controls (nested case-control). Ghrelin was measured using radioimmunoassay. In NIT and SWHS, low ghrelin concentrations were associated with an increased risk of developing GNCA and GCA. The hazard ratio (HR _Q1:Q4 ) for GNCA in NIT was 1.35 (95% CI: 0.89-2.05; p-trend = 0.02); the odds ratio in SWHS was 1.66 (95% CI: 1.02-2.70; p-trend = 0.06). Low ghrelin was associated with a twofold increase of GCA (HR _Q1:Q4 = 2.00, 95% CI: 1.45-2.77; p-trend<0.001). In contrast, a lower risk of ESCC (NIT ESCC HR _Q1:Q4 = 0.65, 95% CI: 0.45-0.92; p-trend = 0.02) was found in NIT. Low baseline ghrelin concentrations were associated with an increased risk for GNCA and GCA in the NIT and the SWHS. In contrast, low ghrelin concentrations at baseline were associated with a reduced risk of developing ESCC in the NIT. Ghrelin may be an early marker of future cancer risk for developing upper gastrointestinal cancer in regions of high incidence.

Effects of IBDV infection on expression of ghrelin and ghrelin-related genes in chicken

Ghrelin is a peptide hormone that plays a modulatory role in the immune system. Studies have demonstrated that mammal ghrelin level is influenced by pathological status. However, it has not been reported whether chicken ghrelin level changes during pathogen infection. This study was designed to investigate changes of ghrelin levels in chickens infected with infectious bursal disease virus (IBDV) and to explore the relationship between ghrelin changes and bursal damage, and inflammatory cells infiltration induced by IBDV. The results showed that (1) plasma ghrelin concentration increased after IBDV infection. It reached a peak at 10443.6 ± 2612.9 pg/mL on 2 dpi, which was about 100-fold as high as that of the control. Then it decreased sharply on 3 dpi, which was only 31.7% as that of 2 dpi, and remained stable until 5 dpi. Meanwhile, ghrelin and ghrelin-related gene, ghrelin-o-acyltransferase (GOAT), and growth hormone secretagogue receptor (GHSR) mRNA expression levels in bursa were also increased after IBDV infection, and reached the peak on 2 dpi at 149, 28.8, and 117.2-fold higher than that of the control, respectively. Then they decreased and remained at a higher status. Correlation analysis showed that plasma ghrelin concentration and ghrelin, GOAT, and GHSR mRNA expressions in bursa were strongly associated with IBDV VP2 mRNA expression in bursa. (2) The damage of bursa was the most severe on 5 dpi with a histopathological score of 12. It had no direct correlation with plasma ghrelin level and ghrelin, GOAT, and GHSR mRNA expressions in bursa. However, the number of inflammatory cells infiltrating into bursa, which was the highest on 2 and 3 dpi, showed significant a positive correlation with the ghrelin and GHSR mRNA expression. Presumably chicken ghrelin may function as an anti-inflammatory factor. In conclusion, IBDV infection upregulates the expression of ghrelin and ghrelin-related gene in chickens, and chicken ghrelin may play an important regulatory role during pathogen infection.

Helicobacter pylori and corpus gastric pathology are associated with lower serum ghrelin

AIM

To evaluate the association of Helicobacter pylori (H. pylori), cagA genotype, and type of gastric pathology with ghrelin, leptin and nutritional status.

METHODS

Fasted dyspeptic adults (18-70 years) referred for an upper digestive endoscopy were enrolled in this cross-sectional study. Height and weight were assessed for body mass index (BMI) calculation. A sociodemographic survey was administered and nutrient intake was evaluated with 24 h dietary recalls. Serum total ghrelin and leptin levels were analyzed by enzyme-linked immunosorbent assay. ¹³C-Urea Breath Test was performed and four gastric biopsies were obtained during endoscopy for histopathology and H. pylori DNA amplification and genotyping. Data analysis was performed using χ², Mann-Whitney U, Kruskal-Wallis tests, Spearman’s correlation and linear regression.

RESULTS

One hundred and sixty-three patients (40.8 ± 14.0 years), 98/65 females/males, were included. Overall, persistent H. pylori prevalence was 53.4% (95%CI: 45.7%-65.8%). Neither nutrient intake nor BMI differed significantly between H. pylori positive and negative groups. Serum ghrelin was significantly lower in infected patients [median 311.0 pg/mL (IQR 230.0-385.5)] than in uninfected ones [median 355.0 pg/mL (IQR 253.8-547.8)] (P = 0.025), even after adjusting for BMI and gender (P = 0.03). Ghrelin levels tended to be lower in patients carrying cagA positive strains both in the antrum and the corpus; however, differences with those carrying cagA negative strains did not reach statistical significance (P = 0.50 and P = 0.49, respectively). In addition, the type and severity of gastric pathology in the corpus was associated with lower serum ghrelin (P = 0.04), independently of H. pylori status. Conversely, leptin levels did not differ significantly between infected and uninfected patients [median 1.84 ng/mL (0.80-4.85) vs 1.84 ng/mL (0.50-5.09), (P = 0.51)].

CONCLUSION

H. pylori infection and severity of gastric corpus pathology are associated with lower serum ghrelin. Further studies could confirm a lower ghrelin prevalence in cagA-positive patients.

Helicobacter pylori infection and serum leptin, obestatin, and ghrelin levels in Mexican schoolchildren

BackgroundThere is little information about the possible role of Helicobacter pylori infection on appetite-regulating peptides in children. This study evaluated the association between H. pylori infection and serum levels of ghrelin, leptin, and obestatin in schoolchildren.MethodsOne hundred seventy-eight schoolchildren, students at boarding schools in Mexico City, participated. H. pylori infection status was determined every 6 months for 1 year by a breath test using ¹³C-urea; schoolchildren with consistently positive or negative results were selected to participate. Age, sex, and body mass index (BMI) were recorded. Serum concentrations of total ghrelin, leptin, and obestatin via specific enzyme-linked immunosorbent assays were determined.ResultsSchoolchildren with H. pylori infection had lower concentration of leptin, -0.54 pg/ml (95% CI: -0.98 to -0.09), compared to the schoolchildren without infection, after adjustment by age, gender, and BMI. And the children with the infection had a median of obestatin lower in 0.99 ng/ml (95% CI: -1.93 to -0.06) compared with the uninfected children after adjustment by BMI.ConclusionAssociation was found between H. pylori infection and decreased serum concentrations of leptin and obestatin. These results suggest that in schoolchildren, H. pylori infection affects the levels of hormones implicated in regulating appetite and energy homeostasis.

Plasma ghrelin level and plasma ghrelin/obestatin ratio are related to intestinal metaplasia in elderly patients with functional dyspepsia

Background

Whether plasma ghrelin/obestatin levels are associated with Helicobacter pylori (H. pylori) infection, subtypes of functional dyspepsia (FD), and gastric mucosal histology has not yet been established in elderly patients.

Objective

The aim of this study was to determine whether plasma ghrelin and obestatin levels are related to gastric mucosal histology, H. pylori infection, and FD subtypes in elderly patients with FD.

Methods

Ninety-two patients diagnosed with FD and older than 60 years (median age 69.4; range 60–88) were included. Clinical symptoms investigated included postprandial fullness, epigastric pain, epigastric soreness, nausea, and vomiting. According to the Rome III criteria, patients diagnosed with FD were divided into two subtypes: epigastric pain syndrome (EPS) and postprandial distress syndrome (PDS). Plasma ghrelin and obestatin levels were measured using enzyme immunoassay, and histological examination of gastric mucosa was performed. H. pylori infection was determined by histopathological examination of gastric mucosal biopsy and/or Campylobacter-like organism test.

Results

In our study, plasma ghrelin levels and plasma ghrelin/obestatin (G/O) ratio were significantly lower in subjects with intestinal metaplasia compared with those without intestinal metaplasia (ghrelin, p = 0.010; G/O ratio, p = 0.012). On the other hand, there were no significant differences in plasma ghrelin and obestatin levels between H. pylori–positive and H. pylori–negative groups. (ghrelin, p = 0.130; obestatin, p = 0.888). Similarly, no significant differences were detected between the EPS and PDS groups (ghrelin, p = 0.238; obestatin, p = 0.710).

Conclusions

Patients with intestinal metaplasia, a known precursor of gastric cancer, had significantly less plasma ghrelin levels and G/O ratio than those without intestinal metaplasia.

Relationship between ghrelin, Helicobacter pylori and gastric mucosal atrophy in hemodialysis patients

AIM

To investigate the relationship between plasma ghrelin level, Helicobacter pylori (H. pylori) infection status and the severity of atrophy in hemodialysis patients.

METHODS

One hundred eights patients who received hemodialysis and 13 non-hemodialysis H. pylori-negative controls underwent gastroduodenoscopy to evaluate the severity of gastric atrophy. Serum levels of pepsinogen (PG) were measured as serum markers of gastric atrophy. H. pylori infection was evaluated by anti-H. pylori IgG antibody, rapid urease test and culture test. We classified H. pylori infection status as non-infection, present infection and past infection. In addition, plasma acyl-ghrelin and desacyl-ghrelin levels were measured by enzyme-linked immunosorbent assay.

RESULTS

Infection rate of H. pylori was 45.4% (49/108). Acyl-ghrelin level in the non-infection group (39.4 ± 23.0 fmol/mL) was significantly higher than in the past (23.4 ± 19.9 fmol/mL, P = 0.005) and present infection groups (19.5 ± 14.0 fmol/mL, P < 0.001). Furthermore, desacyl-ghrelin level in the non-infection group (353.2 ± 190.2 fmol/mL) was significantly higher than those in the past (234.9 ± 137.5 fmol/mL, P = 0.008) and present infection groups (211.8 ± 124.2 fmol/mL, P < 0.001). Acyl-ghrelin was positively correlated with the PG I level and PG I/II ratio (|R| = 0.484, P < 0.001 and |R| = 0.403, P < 0.001, respectively). Both ghrelins were significantly decreased in accordance with the progress of endoscopic atrophy (both P < 0.001) and acyl-ghrelin was significantly lower in patients with mild, moderate and severe atrophy (24.5 ± 23.1 fmol/mL, 20.2 ± 14.9 fmol/mL and 18.3 ± 11.8 fmol/mL) than in those with non-atrophy (39.4 ± 22.2 fmol/mL, P = 0.039, P = 0.002 and P < 0.001, respectively).

CONCLUSION

In hemodialysis patients, plasma ghrelin level was associated with the endoscopic and serological severity of atrophy related to H. pylori infection.

Impact of Helicobacter pylori Immunoglobulin G Levels and Atrophic Gastritis Status on Risk of Metabolic Syndrome

Background

Helicobacter pylori (HP) infection is implicated in gastric and extra-gastric diseases. While gastritis-related chronic inflammation represents a known trigger of metabolic disturbances, whether metabolic syndrome (MetS) is affected by gastritis status remains unclear. We aimed to clarify the effect of HP-related gastritis on the risk of MetS.

Materials and Methods

We retrospectively enrolled patients undergoing screening for MetS between 2014 and 2015. Investigations included HP-specific immunoglobulin G (IgG) antibody assays to detect HP infection, and serum pepsinogen assays to evaluate atrophic gastritis status. The risk of MetS was evaluated via multiple logistic regression analyses with two covariates: serum HP infection status (IgG levels) and atrophic gastritis status (two criteria were applied; pepsinogen I/II ratio < 3 or both pepsinogen I levels ≤ 70 μg/L and pepsinogen I/II ratio < 3).

Results

Of 1,044 participants, 247 (23.7%) were HP seropositive, and 62 (6.0%) had MetS. HP seronegative and seropositive patients had similar risks of MetS. On the other hand, AG (defined in terms of serum PG I/II <3) was significant risk of MetS (OR of 2.52 [95% CI 1.05–7.52]). After stratification according to HP IgG concentration, patients with low HP infection status had the lowest MetS risk (defined as an odds ratio [OR] adjusted for age, sex, smoking, drinking and physical activity status). Taking this result as a reference, patients with negative, moderate, and high HP infection status had ORs (with 95% confidence intervals [CI]) of 2.15 (1.06–4.16), 3.69 (1.12–16.7), and 4.05 (1.05–26.8).

Conclusions

HP-associated gastritis represents a risk factor for MetS. Research should determine why low and not negative HP infection status is associated with the lowest MetS risk.

Changes in plasma ghrelin and leptin levels in patients with peptic ulcer and gastritis following eradication of Helicobacter pylori infection

Background

Helicobacter pylori (H. pylori) infection and eradication therapy have been known to influence gastric ghrelin and leptin secretion, which may lead to weight gain. However, the exact relationship between plasma ghrelin/leptin levels and H. pylori infection has remained controversial. The aim of this study was to investigate plasma ghrelin and leptin levels in H. pylori-positive and -negative patients, to compare the two levels of the hormones before and after H. pylori eradication, and to examine the correlation between body mass index (BMI) and active ghrelin or leptin levels, as well as that between atrophic pattern and active ghrelin or leptin levels.

Methods

Seventy-two H. pylori-positive patients who underwent upper gastrointestinal endoscopy, 46 diagnosed as having peptic ulcer and 26 as atrophic gastritis, were enrolled. Control samples were obtained from 15 healthy H. pylori-negative volunteers. The extent of atrophic change of the gastric mucosa was assessed endoscopically. Body weight was measured and blood was collected before and 12 weeks after H. pylori eradication therapy. Blood samples were taken between 8 and 10 AM after an overnight fast.

Results

Plasma ghrelin levels were significantly lower in H. pylori-positive patients than in H. pylori-negative patients. In particular, plasma active ghrelin levels were significantly lower in patients with gastritis compared with patients with peptic ulcer. Plasma ghrelin levels decreased after H. pylori eradication in both peptic ulcer and gastritis patients, while plasma leptin levels increased only in peptic ulcer patients. Plasma leptin levels and BMI were positively correlated, and active ghrelin levels and atrophic pattern were weakly negatively correlated in peptic ulcer patients.

Conclusion

H. pylori infection and eradication therapy may affect circulating ghrelin/leptin levels. This finding suggests a relationship between gastric mucosal injury induced by H. pylori infection and changes in plasma ghrelin and leptin levels.

Imbalance of Gastrointestinal Microbiota in the Pathogenesis of Helicobacter pylori-Associated Diseases

The development of new nucleotide sequencing techniques and advanced bioinformatics tools has opened the field for studying the diversity and complexity of the gastrointestinal microbiome independent of traditional cultural methods. Owing largely to the gastric acid barrier, the human stomach was long thought to be sterile. The discovery of Helicobacter pylori, the gram-negative bacterium that infects upwards of 50% of the global population, has started a major paradigm shift in our understanding of the stomach as an ecologic niche for bacteria. Recent sequencing analysis of gastric microbiota showed that H. pylori was not alone and the interaction of H. pylori with those microorganisms might play a part in H. pylori-associated diseases such as gastric cancer. In this review, we summarize the available literature about the changes of gastrointestinal microbiota after H. pylori infection in humans and animal models, and discuss the possible underlying mechanisms including the alterations of the gastric environment, the secretion of hormones and the degree of inflammatory response. In general, information regarding the composition and function of gastrointestinal microbiome is still in its infancy, future studies are needed to elucidate whether and to what extent H. pylori infection perturbs the established microbiota. It is assumed that clarifying the role of gastrointestinal communities in H. pylori-associated diseases will provide an opportunity for translational application as a biomarker for the risk of serious H. pylori diseases and perhaps identify specific organisms for therapeutic eradication.

Increase in plasma acyl ghrelin levels is associated with abatement of dyspepsia following Helicobacter pylori eradication

BACKGROUND

Ghrelin has been indicated as one of the etiological factors in functional dyspepsia (FD).

METHODS

We analyzed 179 patients with FD (based on the Rome III criteria) and 103 asymptomatic healthy individuals (controls) who had undergone endoscopy at Seoul National University Bundang Hospital from February 2011 to June 2014. FD patients were classified into three groups by means of a self-reported questionnaire: patients with postprandial distress syndrome (PDS; n = 49), patients with epigastric pain syndrome (EPS; n = 45), and patients with a combination of these two types (mixed group; n = 85). The fasting blood levels of acyl ghrelin and desacyl ghrelin and messenger RNA (mRNA) expression of preproghrelin in the fundic mucosa were measured by ELISAs and reverse transcription quantitative real-time PCR, respectively. One year after participant enrollment, they were measured again in 79 participants and the changes in the values were compared according to Helicobacter pylori eradication or symptom response.

RESULTS

Plasma acyl ghrelin level was lower in the PDS group than in the control and EPS groups (control group 14.1 fmol/mL, PDS group 8.9 fmol/mL, EPS group 13.8 fmol/mL, mixed group 11.3 fmol/mL; P = 0.003 and P = 0.012, respectively). One year after the eradication of H. pylori, plasma acyl ghrelin level was increased and gastric preproghrelin mRNA expression was upregulated (P = 0.004 and P < 0.001, respectively). Patients with abatement of symptoms demonstrated an increase in plasma acyl ghrelin level (from 11.51 to 21.00 fmol/L, P = 0.040).

CONCLUSIONS

Our results suggest that plasma acyl ghrelin plays a role in the development of PDS. H. pylori eradication upregulates preproghrelin mRNA expression and increases plasma acyl ghrelin level, contributing to the abatement of PDS symptoms.

Ghrelin and Leptin Have a Complex Relationship with Risk of Barrett's Esophagus

BACKGROUND

Abdominal obesity is a risk factor for Barrett's esophagus independent of GERD symptoms, but little is understood about the biological mechanisms between obesity and the carcinogenic pathway of esophageal adenocarcinoma.

AIMS

To evaluate whether ghrelin and leptin may partially explain the association between obesity and Barrett's esophagus.

METHODS

We conducted a case-control study using patients with a new diagnosis of Barrett's esophagus (cases) and two control groups frequency matched to cases for age, gender, and geographic region: (1) patients with gastroesophageal reflux disease (GERD) and (2) a sample of the general population. We generated odds ratios using logistic regressions to evaluate quartiles of serum ghrelin or serum leptin, adjusting for known risk factors for Barrett's esophagus. We evaluated potential interaction variables using cross products and ran stratified analyses to generate stratum-specific odds ratios.

RESULTS

A total of 886 participants were included in the analysis. Higher ghrelin concentrations were associated with an increased risk of Barrett's esophagus, when compared to the population controls, but not the GERD controls. Ghrelin concentrations were not associated with the frequency of GERD symptoms, but ghrelin's relationship with Barrett's esophagus varied significantly with the frequency of GERD symptoms. Leptin concentrations were positively associated with at least weekly GERD symptoms among the population controls and were inversely associated with Barrett's esophagus only among the GERD controls. Adjusting for waist circumference did not change the main associations.

CONCLUSION

Higher levels of ghrelin were associated with an increased risk of Barrett's esophagus among the general population. In contrast, leptin was positively associated with frequent GERD symptoms, but inversely associated with the risk of Barrett's esophagus among the GERD controls.

Helicobacter pylori Stool Antigen Levels and Serological Biomarkers of Gastric Inflammation are Associated with Cardio-Metabolic Risk Factors in Type 2 Diabetic Patients

BACKGROUND

Helicobacter pylori infection and subsequent gastric inflammation have been proposed as risk factors for the development of insulin resistance and cardiovascular disease. In this study we assessed the possible association of H. pylori bacterial load, and serum biomarker of gastric inflammation with cardiometabolic risk factors in diabetic patients.

METHODS

In this cross-sectional study, 84 H. pylori-infected type 2 diabetic patients were assessed for anthropometrics, biochemical and clinical measurements. Pearson correlation test, linear, and logarithmic regression curve estimation models were used to assess the association of H. pylori stool antigen (HpSAg) levels, and pepsinogen I (PGI) to pepsinogen II (PGII) ratio with fasting serum glucose, insulin, serum lipid and lipoprotein parameters, malondialdehyde, high-sensitive C-reactive protein (hs-CRP), systolic and diastolic blood pressure, body weight, waist circumference and lipid accumulation product (LAP) index.

RESULTS

The mean age of participants was 54±10 years, and 44% were men. Mean HpSAg levels and PGI/PGII ratio were 0.24±0.23 μg/mL and 9.9±9.0, respectively. Higher HpSAg as well as lower PGI/PGII was correlated with higher anthropometric measures and LAP. A significant negative correlation between PGI/PGII ratio and blood pressure (r=-0.21 and r=-0.22, systolic and diastolic, respectively, P<0.05), serum insulin (r=-0.17, P=0.05), and hs-CRP (r=-0.17, P=0.05) was observed. A significant linear association between PGI/PGII ratio with serum triglycerides (γ=-0.24, P<0.05), serum high density lipoprotein cholesterol (HDL-C; γ=0.43, P<0.01), and triglycerides/HDL-C ratio (γ=-0.28, P<0.05) were observed.

CONCLUSION

Higher H. pylori bacterial load and lower PGI/PGII ratio was associated with higher levels of cardiometabolic risk factors in H. pylori infected type 2 diabetic patients.

Changes in serum ghrelin level in relation to meal-time in patients with functional dyspepsia

BACKGROUND

Ghrelin is a peptide hormone that is involved in gastrointestinal motility and secretion; and therefore, may play a role in functional dyspepsia.

OBJECTIVES

To compare the change of serum ghrelin level in relation to meal-time, between patients with functional dyspepsia and a control group.

MATERIALS AND METHODS

In a cross-sectional study, 18 subjects with functional dyspepsia according to the Rome III criteria were enrolled in our study. Blood samples were collected five times: 30 minutes (min) before a standard breakfast; at the time as serving breakfast; and 30, 60 and 90 min after breakfast. Serum ghrelin concentration was measured in these patients and compared with eight normal individuals, as controls.

RESULTS

The serum ghrelin level 30 minutes after breakfast was significantly higher in dyspepsia patients, compared to controls (751 ± 171.84 pg/ml versus 576.9 ± 195.62 pg/ml, p = 0.033). Although patients had a higher mean serum ghrelin level 30 minutes before, exactly at the time of serving breakfast and 60 min after breakfast there was no statistically significant difference between patients and controls. The shape of the curve was also different between the two groups, from 30 min until 90 min after breakfast, which is the time that most dyspeptic symptoms usually occur, although this difference was not significant (p > 0.05).

CONCLUSION

The significantly different ghrelin levels between dyspeptic patients and the normal population showed that ghrelin may have an important role in inducing symptoms, in functional dyspeptic patients.

Impairment of ghrelin synthesis in Helicobacter pylori-colonized stomach: New clues for the pathogenesis of H. pylori-related gastric inflammation

Ghrelin, the ligand of growth hormone secretagogue receptor 1a, takes part in several functions of the digestive system, including regulation of appetite, energy homeostasis, gastric acid secretion and motility. Ghrelin has also immunoregulatory properties and is supposed to inhibit some inflammatory pathways that can mediate gastric damage. Interestingly, ghrelin synthesis is reduced in the gastric mucosa of patients with Helicobacter pylori (H. pylori) infection, a worldwide condition inducing a T helper (Th)1/Th17 cell response-driven gastritis, which may evolve towards gastric atrophy and cancer. In this article, we review the available data on the expression of ghrelin in H. pylori infection and discuss how the defective ghrelin synthesis may contribute to sustain the ongoing inflammatory response in this disease.

Helicobacter pylori infection in obesity and its clinical outcome after bariatric surgery

The present review summarizes the prevalence and active clinical problems in obese patients with Helicobacter pylori (H. pylori) infection, as well as the outcomes after bariatric surgery in this patient population. The involvement of H. pylori in the pathophysiology of obesity is still debated. It may be that the infection is protective against obesity, because of the gastritis-induced decrease in production and secretion of the orexigenic hormone ghrelin. However, recent epidemiological studies have failed to show an association between H. pylori infection and reduced body mass index. H. pylori infection might represent a limiting factor in the access to bariatric bypass surgery, even if high-quality evidence indicating the advantages of preoperative H. pylori screening and eradication is lacking. The clinical management of infection is complicated by the lower eradication rates with standard therapeutic regimens reported in obese patients than in the normal-weight population. Prospective clinical studies to ameliorate both H. pylori eradication rates and control the clinical outcomes of H. pylori infection after different bariatric procedures are warranted.

Associations of diabetes mellitus, insulin, leptin, and ghrelin with gastroesophageal reflux and Barrett's esophagus

BACKGROUND & AIMS

Insulin and leptin have proliferative and anti-apoptotic effects. Ghrelin promotes gastric emptying and secretion of growth hormone and inhibits inflammation. We assessed whether diabetes mellitus and serum levels of insulin, leptin, and ghrelin are associated with gastroesophageal reflux disease (GERD) and Barrett's esophagus.

METHODS

We conducted a case-control study in 822 men undergoing colorectal cancer screening who were recruited to also undergo upper endoscopy. We identified 70 with Barrett's esophagus; 80 additional men with Barrett's esophagus were recruited shortly after their clinical diagnoses. Serum levels of insulin, leptin, and ghrelin were assayed in all 104 fasting men with Barrett's esophagus without diabetes and 271 without diabetes or Barrett's esophagus. Logistic regression was used to estimate the effects of diabetes and levels of insulin, leptin, and ghrelin on GERD and Barrett's esophagus.

RESULTS

Among men with GERD, diabetes was inversely associated with Barrett's esophagus (adjusted odds ratio [OR] = 0.383; 95% confidence interval [CI]: 0.179-0.821). Among nondiabetics, hyperinsulinemia was positively associated with Barrett's esophagus, but the association was attenuated by adjustment for leptin and ghrelin. Leptin was positively associated with Barrett's esophagus, adjusting for obesity, GERD, and levels of insulin and ghrelin (OR for 3(rd) vs 1(st) tertile = 3.25; 95% CI: 1.29-8.17); this association was stronger in men with GERD (P = .01 for OR heterogeneity). Ghrelin was positively associated with Barrett's esophagus (OR for an increment of 400 pg/mL = 1.39; 95% CI: 1.09-1.76), but inversely associated with GERD (OR for 3(rd) vs 1(st) tertile = 0.364; 95% CI: 0.195-0.680).

CONCLUSIONS

Based on a case-control study, leptin was associated with Barrett's esophagus, particularly in men with GERD. Serum insulin level was associated with Barrett's esophagus, but might be mediated by leptin. Serum ghrelin was inversely associated with GERD, as hypothesized, but positively associated with Barrett's esophagus, contrary to our hypothesis. Additional studies are needed in men and women to replicate these findings.

Helicobacter pylori infection associates with a mucosal downregulation of ghrelin, negative regulator of Th1-cell responses

BACKGROUND

Helicobacter pylori (Hp)-related gastritis is characterized by a predominant T helper (Th)1/Th17 cell immunity. Ghrelin (GR) has immunoregulatory properties and inhibits experimental Th cell-dependent pathology.

AIMS

To evaluate whether Hp infection associates with changes in GR expression and whether GR negatively regulates Th1/Th17 cytokines during Hp infection.

METHODS

GR expression was evaluated by real-time PCR in gastric biopsies taken from Hp-infected and Hp-uninfected patients and in gastric biopsies of Hp-negative subjects cultured with or without H. pylori culture supernatant. To examine whether GR regulates Hp-induced cytokine production, H. pylori-infected gastric biopsies were stimulated with GR, and interleukin (IL)-12, interferon (IFN)-γ and IL-4 transcripts were evaluated by real-time PCR. IL-12 and IFN-γ were also analyzed in lamina propria mononuclear cells (LPMCs) extracted from Hp-infected gastric biopsies and cultured with GR.

RESULTS

GR RNA transcripts were reduced in biopsies from Hp-infected patients. Treatment of Hp-negative gastric biopsies with Hp culture supernatant reduced GR RNA expression. GR dose-dependently inhibited RNA expression of IL-12 and IFN-γ but not IL-4 in ex vivo cultures of mucosal explants and in cultures of gastric LPMCs from Hp-positive patients.

CONCLUSIONS

GR is downregulated in the gastric mucosa of H. pylori-infected patients. Such a defect could contribute to sustain the ongoing Th1-cell response.

Serum ghrelin; a new surrogate marker of gastric mucosal alterations in upper gastrointestinal carcinogenesis

Background

A few studies have indicated inverse relationships between serum ghrelin and gastric and esophageal cancers but those associations have been restricted to specific populations, including smokers and overweight individuals. We examined the association between ghrelin and gastroesophageal cancers and atrophic gastritis in a population-based setting.

Methods

In total 220 gastroesophageal cancers, comprising non-cardia and cardia gastric cancer, esophageal adenocarcinoma, esophageal squamous cell carcinoma (SCC) and age and gender-matched controls were recruited. Serum ghrelin, pepsinogen I/II ratio (PGI/II) and anti-H.pylori IgG antibodies were measured. Relationships between ghrelin and gastroesophageal cancers, after adjustment for PGI/II ratio, H.pylori status and smoking, were tested using logistic regression. Furthermore, in 125 endoscopically normal volunteers, with and without histological atrophic gastritis, the relationship with ghrelin was compared.

Results

Serum ghrelin (lowest vs. highest quintile) was inversely associated with gastric cancer: OR (95% CI) 8.71 (1.70–44.59) for cardia and 6.58 (1.26–34.46) for non-cardia cancer. Lower serum ghrelin was also associated with esophageal SCC: OR (95% CI) 5.69 (1.36–23.78), but not with esophageal adenocarcinoma. A similar association was observed between gastric cancer (cardia and non-cardia) and esophageal SCC when serum ghrelin was analysed as a continuous scaled variable. In endoscopically-normal volunteers, extensive atrophic gastritis was associated with low serum ghrelin [OR (95% CI) 0.25 (0.10–0.64)].

Conclusion

Inverse associations between ghrelin and some gastroesophageal cancers suggest a potential role for serum ghrelin as a biomarker of upper gastrointestinal cancers and atrophic gastritis. In areas with a high incidence of gastric and/or esophageal cancer, screening might be more effectively targeted to individuals with low serum ghrelin in addition to the PGI/II ratio.

Helicobacter pylori and nonmalignant diseases

Declining Helicobacter pylori prevalence rates have resulted in a decrease of peptic ulcer bleeding incidence. Moreover, eradication reduces peptic ulcer recurrence rate. Newer studies confirm that H. pylori eradication lowers the risk of recurrent peptic ulcer bleeding. Guidelines therefore advocate a test-and-treat strategy for patients with a history of ulcer bleeding and NSAIDs and/or aspirin use. There is mounting evidence that H. pylori status has no effect on symptoms and treatment efficacy in patients with gastroesophageal reflux disease (GERD). Some studies observed an improvement of GERD complaints after H. pylori eradication, which underlines that H. pylori treatment is not contra-indicated in GERD patients. The exact role of H. pylori in functional dyspepsia (FD) remains controversial. However, there is growing consensus that H. pylori-positive FD should be assessed as a separate entity. In these patients, eradication can be beneficial and appropriate. Finally, several studies suggest that H. pylori infection may also be associated with beneficial effects for the host. Epidemiologic studies showed an inverse relation between H. pylori infection and asthma and allergy, although data are conflicting and need to be expanded.

Effect of Helicobacter pylori eradication on serum ghrelin and obestatin levels

AIM: To investigate changes in serum ghrelin and obestatin levels before and after Helicobacter pylori (H. pylori) eradication.

METHODS: A total of 92 patients presenting with symptoms of dyspepsia were enrolled in the study. Upper endoscopy was performed on all patients and used to diagnose H. pylori infection according to the presence of characteristic histopathological findings; seventy patients were diagnosed with H. pylori infection and the remaining 22 non-infected patients were classified as healthy controls. H. pylori eradication was accomplished by administering the classical triple therapy drug regimen, consisting of lansoprazole 30 mg bid, amoxicillin 1 g bid, and clarithromycin 500 mg tid for 14 d. The eradication of H. pylori was assessed with C¹⁴-urea breath test, which was performed at eight weeks after treatment. Levels of serum active ghrelin and obestatin were assessed at beginning of the study (prior to treatment) and after eight weeks. The levels were comparatively analyzed between the H. pylori negative control group, the H. pylori eradicated group, and the H. pylori non-eradicated group.

RESULTS: A total of 92 patients, 50 females and 42 males with a mean age of 38.2 ± 11.9 years (range: 19-64), were analyzed. H. pylori eradication success was achieved in 74.3% (52/70) of H. pylori positive patients. The initial levels of ghrelin in the H. pylori positive and control cases were 63.6 ± 19.8 pg/mL and 65.1 ± 19.2 pg/mL (P = 0.78), respectively, and initial obestatin levels were 771 ± 427 pg/mL and 830 ± 296 pg/mL (P = 0.19), respectively. The difference between the initial levels and the week 8 levels of ghrelin and obestatin in the control group was insignificant [4.5% (P = 0.30) and -0.9% (P = 0.65), respectively]. The difference between the initial and week 8 levels of ghrelin and obestatin in the H. pylori non-eradicated group were also insignificant [0.9% (P = 0.64) and 5.3% (P = 0.32), respectively]. The H. pylori eradicated group had a greater change in obestatin levels when compared to the control and the non-eradicated groups (148 ± 381 pg/mL vs -12 ± 138 pg/mL and -72.8 ± 203 pg/mL, respectively, P = 0.015), while decreases in ghrelin levels were insignificant (-7.2 pg/mL vs -1.4 pg/mL and -1.9 pg/mL, respectively, P = 0.52). The ghrelin/obestatin ratio for the initial and week 8 levels changed significantly in only the H. pylori eradicated group (0.11 vs 0.08, respectively, P = 0.015). For overweight patients (as designated by body mass index), we observed significant increases in obestatin levels in the eradicated group as compared to non-eradicated group (201 ± 458 pg/mL vs -5 ± 81 pg/mL, respectively, P = 0.02). In the H. pylori-eradicated group, the levels did not differ between the sexes for ghrelin (-6.3 ± 26.9 pg/mL vs -8.0 ± 24.0 pg/mL, respectively, P = 0.97) or obestatin (210 ± 390 pg/mL vs 96 ± 372 pg/mL, respectively, P = 0.23).

CONCLUSION: Serum levels of ghrelin decreased while obestatin levels increased in H. pylori eradicated subjects, especially in overweight and male patients.

Helicobacter pylori infection in functional dyspepsia

Functional dyspepsia is the most common reason for patients to experience chronic epigastric pain or discomfort. The causes of functional dyspepsia are multifactorial but Helicobacter pylori infection is one likely candidate. Infection with this bacterial pathogen clearly results in chronic mucosal inflammation in the stomach and duodenum, which, in turn, might lead to abnormalities in gastroduodenal motility and sensitivity. Chronic gastritis might also affect a variety of endocrine functions of the stomach including the production of the gastrointestinal hormones and neurotransmitters somatostatin, gastrin and ghrelin. Although these abnormalities might generate symptoms in some patients with functional dyspepsia, the clinical evidence needs to be critically evaluated before this hypothesis can be confirmed. A Cochrane review reported that eradication of H. pylori in these patients had a small but statistically significant long-term effect on symptom relief when compared with placebo, lasting at least 12 months after 1 week of eradication therapy. The efficacy of eradication therapy was seen in all symptom subtypes of functional dyspepsia, but was more marked in Asian than Western patients. This evidence has led to alterations in most of the major guidelines throughout the world, which now recommend H. pylori eradication in patients with functional dyspepsia if they test positive for this bacterium.

Ghrelin in gastrointestinal diseases

Ghrelin is an endogenous ligand of the growth hormone secretagogue receptor (GHSR). Upon binding to its receptor, Ghrelin can produce a variety of biological effects, such as promoting the release of growth hormone and maintaining energy balance. Besides, it also promotes gastrointestinal motility, increases gastric acid secretion, and is involved in the genesis of tumors. This article reviews the role of Ghrelin in gastrointestinal system disease.

Eradication of Helicobacter pylori increases childhood growth and serum acylated ghrelin levels

AIM: To determine whether Helicobacter pylori (H. pylori)-infected children have reduced body weight (BW) and height (BH) growth, and if H. pylori eradication may restore growth while improving serum acylated ghrelin.

METHODS: This longitudinal cohort study with one-year follow-up enrolled 1222 children aged 4 to 12 years old into an observation cohort (18 with and 318 without H. pylori) and intervention cohort (75 with and 811 without). The 7-d triple therapy was used for eradication in the intervention cohort. The net increases of BW and BH as well serum acylated ghrelin after one-year follow-up were compared between successful eradicated H. pylori-infected children and controls.

RESULTS: In the observation cohort, the H. pylori-infected children had lower z score of BW (-1.11 ± 0.47 vs 0.35 ± 0.69, P = 0.01) and body mass index (BMI) (0.06 ± 0.45 vs 0.44 ± 0.73, P = 0.02) at enrollment and lower net BW gain after one-year follow-up (3.3 ± 2.1 kg vs 4.5 ± 2.4 kg, P = 0.04) than the non-infected controls. In the intervention cohort, the H. pylori-infected children had lower z score of BMI (0.25 ± 1.09 vs 0.68 ± 0.87, P = 0.009) and serum acylated ghrelin levels (41.8 ± 35.6 pg/mL vs 83.6 ± 24.2 pg/mL, P < 0.001) than the non-infected controls. In addition to restoring decreased serum ghrelin levels (87.7 ± 38.0 pg/mL vs 44.2 ± 39.0 pg/mL, P < 0.001), the H. pylori-infected children with successful eradication had higher net gains (P < 0.05) and increase of z scores (P < 0.05) of both BW and BH as compared with non-infected controls after one-year follow-up.

CONCLUSION: H. pylori-infected children are associated with low serum acylated ghrelin and growth retardation. Successful eradication of H. pylori restores ghrelin levels and increases growth in children.

Mapping analysis of ghrelin producing cells in the human stomach associated with chronic gastritis and early cancers

OBJECTIVE

The majority of ghrelin producing cells (GPC) are present in the fundic gland of the stomach and recognized as X/A like cells. The detailed distribution of GPC in the stomach is still unknown in healthy and pathological subjects.

METHODS

We investigated the detailed distribution of GPC in the stomach, especially in relation with chronic gastritis, using surgical specimens from 12 patients with early gastric cancer. Either the anterior or posterior half of the whole stomach, which was a counterpart of the tumor bearing side, was subjected for immunohistochemistry of ghrelin, and the number of total GPC were semi quantitatively evaluated as GPC score. GPC score was compared with the degree of chronic gastritis, serum ghrelin concentration and body weight.

RESULTS

GPC was not observed in the pyloric gland, but heterogeneously distributed in the fundic gland mainly in upper body and the greater curvature. The GPC score showed about nine-fold difference, which correlated well with the degree of chronic gastritis by Sydney score (r = -0.84, P < 0.001). The serum ghrelin concentration was basically determined by the GPC score (r = 0.75, P = 0.0047); however, the obese patients showed low serum ghrelin concentration in spite of the presence of abundant GPCs. In the low GPC score patients, serum ghrelin was constantly low regardless of their body weight.

CONCLUSIONS

GPC was inversely correlated with progression of chronic gastritis. Its quantification using immunohistochemistry of the whole stomach was useful to comprehensively evaluate ghrelin profile.

Plasma ghrelin isoforms and gastric ghrelin O-acyltransferase expression are influenced by Helicobacter pylori status

OBJECTIVE

Helicobacter pylori is known to affect the host's nutritional status. This study was performed to elucidate the relationship between H. pylori status and the dynamics of the ghrelin system, in the context of ghrelin O-acyltransferase (GOAT) expression.

METHODS

We conducted a clinical study of 30 subjects focusing on the following points: 1) the effects of H. pylori infection on the concentrations of circulating ghrelin isoforms and on ghrelin and GOAT mRNA expression in the gastric mucosa, and 2) the effects of H. pylori eradication on the same parameters.

RESULTS

The plasma acyl-ghrelin and desacyl-ghrelin concentrations of 16 H. pylori positive participants were significantly lower than those of 14 H. pylori negative controls. The acyl-ghrelin/desacyl-ghrelin ratio was not significantly different between the H. pylori positive and H. pylori negative participants. The levels of ghrelin and GOAT mRNA in the gastric mucosa were significantly lower in the H. pylori positive participants than in the H. pylori negative controls. In 11 subjects in whom H. pylori eradication was successful, their plasma acyl-ghrelin levels tended to increase after H. pylori eradication, but the difference was not significant; however, their plasma desacyl-ghrelin levels were significantly reduced. Although gastric ghrelin mRNA expression increased significantly after H. pylori eradication, gastric GOAT mRNA expression tended to increase but was not significantly altered.

CONCLUSION

H. pylori status might affect the host's nutritional status through changes in the plasma levels of ghrelin isoforms and the gastric expression levels of ghrelin and GOAT mRNA.

Enhanced expression of CXCL13 in human Helicobacter pylori-associated gastritis

BACKGROUND AND AIMS

Chemokine CXC ligand 13 (CXCL13) and CXC receptor type 5 (CXCR5) are constitutively expressed in tertiary lymphoid follicles where the CXCL13/CXCR5 system regulates B lymphocytes homing. In this study, we sought to examine CXCL13 expression in the H. pylori-infected and -uninfected gastric mucosa and to elucidate the implication in the pathogenesis of HAG in humans.

METHODS

Using endoscopic biopsies taken from the gastric antrum of 29 subjects infected with Helicobacter pylori and 22 uninfected subjects, mucosal CXCL13 mRNA and protein levels were measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively.

RESULTS

The CXCL13 expression levels were significantly more elevated in H. pylori-positive patients than uninfected ones. The CXCL13 expression levels correlated with the degree of chronic gastritis and bacterial colonization. Immunohistochemistry and in vitro infection assay showed that CXCL13 was not produced by the gastric epithelium, but the α-smooth muscle antigen expressing mesenchymal cells were the possible source of CXCL13 within H. pylori-infected gastric mucosa. CXCR5 immunostaining was seen in the CD20-positive lymphoid aggregates.

CONCLUSIONS

The enhanced induction of CXCL13 may be involved in the pathogenesis of H. pylori-associated gastritis.

Interferon-γ inhibits ghrelin expression and secretion via a somatostatin-mediated mechanism

AIM: To investigate if and how the proinflammatory cytokine interferon γ (IFNγ) affects ghrelin expression in mice.

METHODS: The plasma concentration of ghrelin, and gastric ghrelin and somatostatin expression, were examined in wild-type mice and mice infected with Helicobacter pylori (H. pylori). Furthermore, ghrelin expression was examined in two achlorhydric mouse models with varying degrees of gastritis due to bacterial overgrowth. To study the effect of IFNγ alone, mice were given a subcutaneous infusion of IFNγ for 7 d. Finally, the influence of IFNγ and somatostatin on the ghrelin promoter was characterized.

RESULTS: H. pylori infection was associated with a 50% reduction in ghrelin expression and plasma concentration. Suppression of ghrelin expression was inversely correlated with gastric inflammation in achlorhdyric mouse models. Subcutaneous infusion of IFNγ suppressed fundic ghrelin mRNA expression and plasma ghrelin concentrations. Finally, we showed that the ghrelin promoter operates under the control of somatostatin but not under that of IFNγ.

CONCLUSION: Gastric infection and inflammation is associated with increased IFNγ expression and reduced ghrelin expression. IFNγ does not directly control ghrelin expression but inhibits it indirectly via somatostatin.

The relationship between serum ghrelin and the risk of gastric and esophagogastric junctional adenocarcinomas

BACKGROUND

Cancers of the upper gastrointestinal tract remain a substantial cause of morbidity and mortality worldwide. Ghrelin is a hormone produced in the oxyntic glands of the stomach, and under conditions of chronic inflammation and atrophy, serum ghrelin concentrations decrease. However, the relationship between ghrelin and the risk of gastric and esophagogastric junctional cancers has not been investigated.

METHODS

We conducted a nested case-control study within the Finnish Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study to examine the relationship between serum ghrelin concentration and the risk of gastric noncardia adenocarcinoma (GNCA) and esophagogastric junctional adenocarcinoma (EGJA). Data from 261 GNCA patients, 98 EGJA patients, and 441 control subjects were analyzed. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using logistic regression with adjustment for potential confounders. Lag analysis was also performed to investigate the temporal nature of the associations between baseline serum pepsinogen I and ghrelin in GNCA and EGJA patients. All statistical tests were two-sided.

RESULTS

Lower concentrations of serum ghrelin were statistically significantly associated with an increased risk of both GNCA (adjusted OR = 1.75, 95% CI = 1.49 to 2.04; P < .001) and EGJA (adjusted OR = 1.56, 95% CI = 1.28 to 1.89, P < .001). A multivariable model found that the risk of both GNCA and EGJA were statistically significantly increased for those individuals in the lowest quartile of serum ghrelin levels compared with those in the highest quartile (OR of GNCA = 5.63, 95% CI = 3.16 to 10.03; OR of EGJA = 4.90, 95% CI = 2.11 to 11.35). The statistical significance of these associations remained even after restricting the analysis to those patients who developed cancer more than 10 years after baseline serum ghrelin measurements.

CONCLUSION

Low baseline concentrations of serum ghrelin were associated with a statistically significant increase in the risk of GNCA and EGJA, suggesting a potential role for gastric hormones in carcinogenesis.

Ghrelin in gastrointestinal disease

Enteroendocrine cells of the gastric fundus are the predominant source of ghrelin production, although ghrelin gene transcripts and ghrelin-producing cells have been identified throughout the gastrointestinal tract. Various infectious, inflammatory and malignant disorders of the gastrointestinal system have been shown to alter ghrelin production and secretion and consequently to affect endocrine ghrelin levels and activity. Animal studies have demonstrated that ghrelin and synthetic ghrelin mimetics can reduce the severity of gastric and colonic inflammation and human clinical trials are underway to determine the efficacy of ghrelin in improving motility disorders. This review summarises the impact of gastrointestinal disease on ghrelin synthesis and secretion and the potential use of ghrelin and its mimetics for the treatment of these diseases.

The effect of Helicobacter pylori and economic status on growth parameters and leptin, ghrelin, and insulin-like growth factor (IGF)-I concentrations in children

BACKGROUND

It was suggested that gastric colonization with Helicobacter pylori (H. pylori) was associated with suboptimal nutrition and growth in childhood. Furthermore, several studies indicated a relationship between H. pylori colonization and alterations in the circulating levels of growth-related molecules (GRM). Accordingly, in this study, we investigate the effect of H. pylori infection on GRMs and on the growth of healthy school children, taking into consideration the effect of their economic status (ES) and anthropometric indices of their parents.

METHODS

To acquire sociodemographic and anthropometric nutritional parameters and to detect H. pylori-specific serum IgG antibodies and growth-related molecules, we evaluated a total of 473 children attending four different primary and secondary schools in Istanbul. Subsequently, we assessed the effect of H. pylori on growth-related parameters (weight for age SDS, height for age SDS, BMI SDS, TSF, and waist-to-hip ratio) and on GRMs (leptin, ghrelin, and insulin-like growth factor-1 (IGF-1)), controlling for age, gender, family income, household crowding (HC), breastfeeding, maternal and paternal BMI SDS, and midparental height SDS with complex statistical models.

RESULTS

Of the 473 children (275 F/198 M, age 6-15 years; mean: 10.3 ± 0.1 years), 161 (34%) were H. pylori-positive. The prevalence of H. pylori was significantly higher in lower economic status (ES) groups, in children living in crowded houses, and in older age groups. Using simple statistical models, we did not find any significant associations between H. pylori infection and the growth parameters. However, in complex models for height for age SDS and for weight for age SDS, there was a significant interaction between H. pylori infection status and ES. Whereas in H. pylori-positive subjects, mid-income family children were both taller and heavier than the low-income group, there was no such an association in H. pylori-negative subjects. Among biochemical parameters, only ghrelin levels were associated with H. pylori infection in all models. Leptin levels were associated with HC in girls, whereas none of the parameters was significantly associated with leptin levels in boys. For IGF-1 levels, for boys, age and maternal BMI, and for girls, age and HC were significantly associated with IGF-1 levels.

CONCLUSION

We suggest that H. pylori may impair growth significantly only in susceptible children where unfavorable socioeconomic conditions facilitate its action, probably through mechanisms, at least in part, involving growth-related molecules.

Helicobacter pylori infection and circulating ghrelin levels - a systematic review

BACKGROUND

The nature of the association between ghrelin, an orexigenic hormone produced mainly in the stomach, and Helicobacter pylori (H pylori), a bacterium that colonises the stomach, is still controversial. We examined available evidence to determine whether an association exists between the two; and if one exists, in what direction.

METHODS

We reviewed original English language studies on humans reporting circulating ghrelin levels in H pylori infected and un-infected participants; and circulating ghrelin levels before and after H pylori eradication. Meta-analyses were conducted for eligible studies by combining study specific estimates using the inverse variance method with weighted average for continuous outcomes in a random effects model.

RESULTS

Seventeen out of 27 papers that reported ghrelin levels in H pylori positive and negative subjects found lower circulating ghrelin levels in H pylori positive subjects; while 10 found no difference. A meta-analysis of 19 studies with a total of 1801 participants showed a significantly higher circulating ghrelin concentration in H pylori negative participants than in H pylori positive participants (Effect estimate (95%CI) = -0.48 (-0.60, -0.36)). However, eradicating H pylori did not have any significant effect on circulating ghrelin levels (Effect estimate (95% CI) = 0.08 (-0.33, 0.16); Test for overall effect: Z = 0.67 (P = 0.5)).

CONCLUSIONS

We conclude that circulating ghrelin levels are lower in H pylori infected people compared to those not infected; but the relationship between circulating ghrelin and eradication of H pylori is more complex.

Helicobacter pylori infection and circulating ghrelin levels - a systematic review

Background

The nature of the association between ghrelin, an orexigenic hormone produced mainly in the stomach, and Helicobacter pylori (H pylori), a bacterium that colonises the stomach, is still controversial. We examined available evidence to determine whether an association exists between the two; and if one exists, in what direction.

Methods

We reviewed original English language studies on humans reporting circulating ghrelin levels in H pylori infected and un-infected participants; and circulating ghrelin levels before and after H pylori eradication. Meta-analyses were conducted for eligible studies by combining study specific estimates using the inverse variance method with weighted average for continuous outcomes in a random effects model.

Results

Seventeen out of 27 papers that reported ghrelin levels in H pylori positive and negative subjects found lower circulating ghrelin levels in H pylori positive subjects; while 10 found no difference. A meta-analysis of 19 studies with a total of 1801 participants showed a significantly higher circulating ghrelin concentration in H pylori negative participants than in H pylori positive participants (Effect estimate (95%CI) = -0.48 (-0.60, -0.36)). However, eradicating H pylori did not have any significant effect on circulating ghrelin levels (Effect estimate (95% CI) = 0.08 (-0.33, 0.16); Test for overall effect: Z = 0.67 (P = 0.5)).

Conclusions

We conclude that circulating ghrelin levels are lower in H pylori infected people compared to those not infected; but the relationship between circulating ghrelin and eradication of H pylori is more complex.

Covariation of plasma ghrelin and motilin in irritable bowel syndrome

We have previously shown that ghrelin is mainly localized to the stomach but also occurs, together with the prokinetic hormone motilin, in endocrine cells in the proximal small intestine. This study explored ghrelin and motilin concentrations in plasma in relation to gastrointestinal motility and whether plasma ghrelin is changed in patients with irritable bowel syndrome (IBS). Nine patients with severe IBS and 10 healthy subjects underwent stationary antro-duodeni-jejunal manometry; blood was sampled during similar motility phases in the two groups. The motility phases were monitored and blood samples were collected during fasting and after food intake. Plasma was analyzed for two forms of ghrelin (octanylated and desoctanylated) as well as for motilin. In IBS patients circulating motilin levels covaried with total ghrelin levels (r=0.90; p<0.004), octanylated ghrelin (r=0.77; p<0.02) and desoctanylated ghrelin (r=0.69; p<0.04). No such correlations were seen in the control group. Octanylated ghrelin comprised 35.3+/-3.9% (mean+/-SEM) of the total circulating ghrelin in the IBS patients compared to 40.4+/-4.5% (mean+/-SEM) in the control group (NS). Ghrelin covaried with motilin in plasma in IBS but not in plasma from healthy subjects. This suggests the two peptides act together in IBS.

Exogenous ghrelin regulates proliferation and apoptosis in the hypotrophic gut mucosa of the rat

Ghrelin is the natural endogenous ligand for growth hormone secretagogue receptors. This peptide regulates energy homeostasis and expenditure and is a potential link between gut absorptive function and growth. We hypothesized that ghrelin may induce a proliferative and antiapoptotic action promoting the recovery of the hypotrophic gut mucosa. Therefore, the aim of the study was to determine the action of exogenous ghrelin following gut mucosal hypotrophia in rats fed an elemental diet. An elemental diet provides readily absorbable simple nutrients and is usually given to patients with absorptive dysfunction. Male Wistar rats ( n = 48) were fed the elemental diet for one week to induce mucosal hypotrophy and then treated for another week with systemic ghrelin and pair-fed with either a normoproteic or hyperproteic isocaloric liquid diet. Another group received a standard diet instead of the elemental diet and served as control (normotrophy). The elemental diet induced intestinal hypotrophia characterized by decreased proliferation in the ileum and increased apoptosis in jejunum and ileum. Ghrelin administration restored normal levels of proliferation in the ileum and apoptosis in the jejunum, with partial apoptosis restoration in the ileum. Ghrelin levels in plasma and fundus were increased in all groups, although the highest levels were found in rats treated with exogenous ghrelin. Ghrelin administration has a positive effect in the hypotrophic gut, regulating both proliferation and apoptosis towards a physiological balance counteracting the negative changes induced by an elemental diet in the intestines.

Magnifying endoscopic observation with narrow band imaging for specialized intestinal metaplasia in barrett's esophagus with special reference to light blue crests

AIM

Barrett's esophagus (BE) with specialized intestinal metaplasia (SIM) is at high risk of esophageal adenocarcinoma. Magnified endoscopy with narrow band imaging (ME-NBI) can be useful for detecting this condition. In addition to pit patterns, light blue crests (LBC), blue-whitish patchy areas on the metaplastic epithelia of the stomach, can predict SIM in BE under ME-NBI observation.

METHODS

A total of 54 patients with BE underwent ME-NBI to identify IM pits (tubular and villous pits) and LBC. Biopsy samples were taken for histological evaluation of IM, immunohistochemical staining for CD10, MUC2 and MUC5AC antigen, transmission electron microscopy and real-time polymerase chain reaction (RT-PCR) analysis of CD10 mRNA expression.

RESULTS

IM pit pattern with ME-NBI for the diagnosis of IM yielded acceptable sensitivity, specificity and accuracy at 92%, 77% and 83%, respectively. However, the sensitivity, specificity and accuracy of LBC with ME-NBI for IM were comparably high at 79%, 97% and 89%, respectively. Upon immunohistochemistry, all 19 metaplastic epithelia of LBC-positive BE showed immunoreactivity against anti-MUC2 antibody, whereas CD10 antigen was identified in 11 of the 19 LBC-positive BE. Brush borders were seen on IM epithelia using electron microscopy. On real-time PCR analysis, CD10 mRNA levels in the LBC-positive BE were higher compared to those in the LBC-negative BE.

CONCLUSION

The appearance of LBC can be an accurate sign to predict SIM in BE and may be associated with high CD10 expression, possibly along with brush borders.

The ghrelin-positive cells number is increased in duodenum in children with celiac disease

Ghrelin is predominately produced in the stomach, but new findings indicate that the intestinal wall is an important source of the hormone. In patients with shortbowel syndrome, reduction in the intestinal tissue resulted in a decrease in the circulating ghrelin levels. Since in celiac disease (CD) intestinal mucosa atrophy is the main finding, alterations in duodenal ghrelin-positive cell population can be expected. The aim of the study was to evaluate the density of ghrelin-positive cells in the duodenum of CD children and its relationship with body mass index (BMI) and clinical presentation. The study included 31 consecutive patients with newly diagnosed CD [BMI SD scores (BMISDS) -0.926+/-1.496]. The control group consisted of 21 children (BMISDS -0.517+/-1.186], diagnosed with growth retardation, anemia or abdominal pain. All the patients underwent endoscopy with biopsy samples taken from distal duodenum. Immunohistochemistry was performed using rabbit anti- ghrelin (human) antiserum. The number of ghrelin-positive cells in the duodenum was significantly higher in children with CD than in controls (14.82+/-11.12 vs 5.69+/-5.02, p<0.0013). The density of ghrelin-positive cells in the duodenum did not correlate with age, pubertal status, BMISDS or clinical presentation. In the duodenum of CD children, the number of ghrelin-positive cells is increased compared with the control patients. The population of ghrelin-positive cells in the duodenum does not simply reflect an altered mucosal morphology or failure to thrive but is under the influence of other conditions.

Eradication of Helicobacter pylori increases ghrelin mRNA expression in the gastric mucosa

It has been suggested that Helicobacter pylori eradication may influence production of some peptides in the stomach, which can affect appetite. This hypothesis is controversial. To verify the hypothesis, we conducted this randomized controlled trial using H. pylori infected subjects without any gastrointestinal symptoms. The treatment group received triple H. pylori eradication therapy for 7 days and the control group received no medication. We measured ghrelin, obestatin and the tumor necrosis factor-alpha (TNF-alpha) mRNA levels in endoscopic biopsy specimens and the changes from baseline to follow-up. The plasma active n-octanoyl ghrelin and obestatin levels were measured in both groups. The ghrelin/obestatin ratios in plasma and gastric mRNA expression were calculated at baseline and follow-up. Ghrelin mRNA expression in the fundic mucosa after H. pylori eradication increased significantly compared to the control group (4.47+/-2.14 vs. 1.79+/-0.96, P=0.009), independent of inflammatory changes. However, obestatin mRNA expression decreased in the antral mucosa (-0.57+/-1.06 vs. 0.41+/-0.72, P=0.028). The treatment group showed a marginal increase (P=0.060) in plasma ghrelin/obestatin ratio. The TNF-alpha mRNA expression also decreased significantly with treatment. This randomized controlled trial demonstrates that H. pylori eradication increases ghrelin mRNA expression, independent of inflammatory cell changes.

Gastric ghrelin in relation to gender, stomach topography and Helicobacter pylori in dyspeptic patients

AIM: To investigate the level of gastric ghrelin in stomach mucosa of dyspeptic patients in relation to Helicobacter pylori (H pylori) infection, bacterial cytotoxicity, topography and gender.

METHODS: The study comprised 40 premenopausal women (19 H pylori positive) and 48 men (17 H pylori positive) with functional dyspepsia. All gastric biopsy specimens revealed normal mucosa or non-atrophic gastritis. Gastric ghrelin concentration was determined by Enzyme linked immunosorbent assay. The cagA and vacA strains of bacterial DNA were identified by multiplex polymerase chain reaction.

RESULTS: In general, infection with H pylori caused an increase in gastric ghrelin level regardless of gender and stomach topography. Significantly more hormone was present in both, non-infected and H pylori positive female samples, as compared to males. The distribution of bacterial strains showed cagA(+) vacA s1m1 and cagA(-) vacA s2m2 genotypes as the most common infections in the studied population. A tendency to higher ghrelin levels was observed in less cytotoxic (cagA negative) strain-containing specimens from the antrum and corpus of both gender groups (without statistical significance).

CONCLUSION: An increase in gastric ghrelin levels at the stage of non-atrophic gastritis in H pylori positive patients, especially in those infected with cagA(-) strains, can exert a gastroprotective effect.

Role of obesity in Barrett's esophagus and cancer

The incidence of esophageal adenocarcinoma (EAC) has increased dramatically in the western world, and there also appears to have been an increase in the incidence of Barrett's esophagus and gastroesophageal reflux disease in recent years. The contemporaneous increase in obesity has focused interest on whether obesity is a risk factor for EAC and its precursors. This article reviews current evidence for the role that overweight/obesity and body fat distribution have in development of the esophagitis metaplasia-dysplasia-adenocarcinoma sequence. Particular attention is paid to the stage at which adiposity may act to influence the risk of EAC, because this determines the importance of weight control and weight loss at each stage in the disease spectrum for the prevention of EAC.

Study of association between atrophic gastritis and body mass index: a cross-sectional study in 10,197 Japanese subjects

OBJECTIVES

The aim of this study was to elucidate the association between body mass index (BMI) and both Helicobacter pylori and atrophic gastritis.

METHODS

The study involved 10,197 subjects participating in a Japanese mass endoscopic gastric cancer screening program. Atrophic gastritis was assessed by pepsinogen I to II ratio.

RESULTS

In logistic regression models, BMI had an inverse association with atrophic gastritis, with the odds ratios (OR) decreasing progressively to 0.67 (95% confidence interval [CI] 0.57-0.79, P<0.0001) in the highest BMI quintiles (BMI >or=25.66) group compared with the lowest BMI quintiles (BMI <20.97) group. In linear regression models, atrophic gastritis predicted BMI (regression coefficient -0.326, 95% CI -0.469, -0.184, P<0.0001), whereas H. pylori antibody was not a predictor (regression coefficient 0.072, 95% CI -0.053, 0.198, P=0.3).

CONCLUSIONS

A small, inverse association between BMI and atrophic gastritis was found in the general population. In contrast, no association was observed between H. pylori seropositivity and BMI.