Autonomic and cytokine mechanisms of acute electroacupuncture in a rodent model of functional dyspepsia

BACKGROUND

Cytokines have been presumed to play an important role in the pathophysiology of functional dyspepsia (FD). Electroacupuncture (EA) has been used for FD treatment; however, its mechanisms remain largely unknown. This study aimed to (1) compare the plasma levels of cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-10, in "FD" rats with normal control rats; (2) investigate whether EA, using chronically implanted electrodes, could inhibit the release of these cytokines; and (3) explore the correlation of cytokine levels with plasma norepinephrine (NE) levels and gastric emptying (GE).

METHODS

A rodent model of FD was established via neonatal treatment with intragastric iodoacetamide. After 8 weeks, the rats were implanted with electrodes at acupoint ST36 for EA. The plasma levels of cytokines and NE were measured using enzyme-linked immunosorbent assay. We explored the correlations of cytokine levels with NE levels and GE.

KEY RESULTS

(i) "FD" rats demonstrated increased levels of TNF-α, IL-1β, and IL-6 (p < 0.05 each) compared with the control rats. (ii) EA significantly decreased the plasma levels of TNF-α, IL-1β, and IL-6 in "FD" rats (p < 0.05 each) compared with sham EA. (iii) The plasma levels of NE were positively correlated with those of IL-6 (r = 0.86, p < 0.05) and IL-1β (r = 0.81, p < 0.05), whereas NE levels and GE were negatively correlated with IL-10 levels (r = -0.870, p < 0.05 and r = -0.791, p < 0.05, respectively).

CONCLUSIONS

EA inhibits the release of proinflammatory cytokines probably via the suppression of sympathetic activity in "FD" rats.

Association between genetic polymorphisms of NOD1, Interleukin-1B, and cagA strain with low-grade duodenal eosinophilia in Helicobacter pylori-related dyspepsia

BACKGROUND

Functional dyspepsia (FD) is a multifactorial disorder. Helicobacter pylori (H. pylori)-related dyspepsia (HpD) may be considered a separate entity. Duodenal eosinophilia is a potential pathogenic mechanism in FD. However, the impact of duodenal eosinophilia and host genetic polymorphism of innate and pro-inflammatory cascade, nucleotide-binding oligomerization domain 1 (NOD-1), and interleukin-1 beta (IL-1β) in HpD was not explored.

AIM

To evaluate the association of NOD1-796G>A and IL-1B-511C>T gene variants and low-grade duodenal eosinophilia in HpD.

METHODS

A multicenter cross-sectional study was conducted. A total of 253 patients who met Rome-IV criteria were selected before upper endoscopy and 98 patients were included after unremarkable upper endoscopy and positive H. pylori in gastric biopsies were assessed. Clinical parameters, H. pylori cagA and duodenal histology, were evaluated.

RESULTS

Sixty-four (65%) patients had epigastric pain syndrome (EPS), 24 (25%) postprandial distress syndrome (PDS), and 10 (10%) EPS/PDS overlap. FD subtypes were not associated with NOD1-796G>A and IL-1B-511C>T gene variants. Low-grade duodenal eosinophilia was significantly increased in NOD1-796 GG versus single A-allele, but not in IL-1B-511 single T-allele or CC-allele. This association is dependent of cagA infection, since harboring cagA strain was significantly associated with low-grade duodenal eosinophilia with isolated variants NOD1-796 GG and IL-1B-511 single T-allele, but not without cagA. When we performed combined polymorphism analysis with NOD1-796 GG/IL-1B-511 single T-allele, a synergistic effect on low-grade duodenal eosinophilia was found between these two loci irrespective of cagA strain status in HpD.

CONCLUSION

Our findings suggest that low-grade duodenal eosinophilia is significantly associated with NOD1-796 GG allele specially in cagA strain and with allelic combination NOD1-796 GG/IL-1B-511 single T-allele independent of cagA strain infection in HpD patients.

Low-grade duodenal eosinophilia is associated with cagA in Helicobacter pylori-related dyspepsia

BACKGROUND AND AIM

Functional dyspepsia (FD) is a multifactorial disorder. Helicobacter pylori (H. pylori)-related dyspepsia (HpD) may be considered a separate entity. Duodenal eosinophilia is a potential pathogenic mechanism in FD. However, the impact of duodenal eosinophilia and H. pylori virulence genes in HpD was not explored. We aim to evaluate the association of H. pylori virulence genes and low-grade duodenal eosinophilia in HpD.

METHODS

A multi-center cross-sectional study was conducted. A total of 301 patients who meet Rome-III criteria were selected before upper endoscopy, and 95 patients were included after normal endoscopy and positive H. pylori in gastric biopsies were assessed. Clinical parameters, H. pylori virulence genes (cagA, oipA, and vacA) and duodenal histology were evaluated.

RESULTS

Sixty-nine (72%) patients had epigastric pain syndrome (EPS), 17 (18%) post-prandial distress syndrome (PDS) and 9 (10%) EPS/PDS overlap. FD syndromes were not associated with cagA or oipA strains. A significantly trend of vacA s1/m1 (78%) and s1/m2 (80%) positive strains in EPS was observed. Histological duodenal grading of chronic inflammation, low-grade duodenal eosinophilia and intra-epithelial lymphocytes showed no difference in oipA and vacA strains. Low-grade duodenal eosinophilia was significant in cagA positive strain, and the OR for low-grade duodenal eosinophilia with H. pylori cagA positive strain was 4.2 (95% CI, 1.78-9.93). Adjusting for age, gender, smoking, diabetes, alcohol, PPI, and NSAID, the OR was 5.44 (1.989-14.902).

CONCLUSION

Our findings suggest that low-grade duodenal eosinophilia is significantly associated with cagA strain in HpD.

Current and emerging therapeutic options for the management of functional dyspepsia

Introduction: Functional Dyspepsia (FD), defined as chronic symptoms originating from the gastroduodenal region in absence of readily identifiable organic disease, is one of the most common gastrointestinal disorders. FD is divided into two subgroups: Post-Prandial Distress Syndrome (PDS) or meal-related FD, characterized by postprandial fullness and early satiation, and Epigastric Pain Syndrome (EPS) or meal-unrelated FD, characterized by epigastric pain and burning.Areas covered: This review summarizes the existing and off-label therapeutic options for FD.Expert opinion: The identification of mechanisms, the Rome IV classification, the reduction of PDS/EPS overlap and pictograms for symptom identification allow a better diagnosis and a more targeted treatment choice. Acotiamide, a first-in-class prokinetic agent available only in Japan and India, is the only agent of proven efficacy for FD, but clinicians use acid-suppressive therapy, prokinetics, neuromodulators and herbal therapies for treating FD symptoms. New emerging targets are duodenal low-grade inflammation with eosinophils and duodenal or other modified luminal microbiota.

Transient elevation of anti-transglutaminase and anti-endomysium antibodies in Giardia infection

Markers of celiac disease (CeD) may be elevated in various conditions of intestinal inflammation or autoimmune disease. Recent reports argue that intestinal infection may induce development of CeD in susceptible individuals. Serum anti-tissue transglutaminase (tTG) and anti-endomysium antibodies (EMA) have been proposed in previous reports to be helpful in differentiating between giardiasis and CeD. In this report, we describe eight cases with elevated CeD serological markers and pathological duodenal histology during, or shortly after, Giardia infection. We present follow-up clinical and serological findings to determine which of these that were diagnosed with CeD. Serum levels of tTGand EMA did not discriminate well between patients where CeD was excluded, and those who were later diagnosed with CeD. The value of these serological CeD markers is discussed in relation to CeD diagnosis in cases with chronic or recent giardiasis.

Immunopathological and molecular basis of functional dyspepsia and current therapeutic approaches

INTRODUCTION

Functional dyspepsia (FD) is widespread with 20% prevalence worldwide and a significant economic burden due to health care cost and constraints on daily activities of patients. Despite extensive investigation, the underlying causes of dyspepsia in a majority of patients remain unknown. Common complaints include abdominal discomfort, pain, burning, nausea, early satiety, and bloating. Motor dysfunction of the gut was long considered a major cause, but recent investigations suggest immune-based pathophysiological and molecular events in the duodenum are more probable contributing factors. Areas Covered: Inflammatory mediators and immune cells including duodenal eosinophils, intraepithelial lymphocytes, and T-cells have been implicated in the underlying cause of disease process, as have genetic factors. In this article, we critically reviewed findings, identified gaps in knowledge and suggested future directions for further investigation to identify targets and develop better therapeutic approaches. Expert commentary: Impaired gastric accommodation, slow gastric emptying, and increased visceral sensitivity have long been thought of as main causal factors of FD. However, more recent identification of eosinophilic degranulation and recruitment of T cells that induce mild duodenal inflammation are giving rise to new insights into immune-mediated pathophysiology. These insights offer promising avenues to explore for immune-mediated therapy in the future.

Non-Specific Gastric Inflammation in Children is Associated with Proton Pump Inhibitor Treatment for More than 6 Weeks

BACKGROUND AND AIMS

Non-specific gastric inflammation (NSGI) is a commonly reported pathological finding. We investigated if it is associated with the use of proton pump inhibitors (PPIs) in children at a single tertiary center.

METHODS

We performed an IRB-approved chart review of all endoscopy and biopsy reports of patients who underwent esophagogastroduodenoscopy between July 2009 and July 2010 (n = 310). Demographic data, dose, duration of exposure to PPI, and biopsy results were collected and analyzed. All esophageal, gastric, and duodenal biopsies were independently reviewed by a pathologist. Patients with acute gastritis, moderate/severe chronic gastric inflammation, or Helicobacter pylori infection were excluded. The presence of NSGI was compared between patients exposed and not exposed to PPI as well as between patients with different doses and durations of PPI exposure to assess for potential associations.

RESULTS

A total of 193 patients were included: 88 (46%) had a history of PPI use and 48 (25%) were found to have NSGI. Compared to patients not exposed to PPI, the odds ratio of NSGI in patients exposed to PPIs was 2.81 (95% CI: 1.36-5.93). The odds ratio of NSGI in patients exposed to PPI for >3 months was 4.53 (95% CI: 1.69-11.97). Gender, ethnicity, and age were not associated with NSGI. No histological differences were found in the esophagus and duodenum between patients exposed and not exposed to PPI.

CONCLUSION

This study found that PPI exposure is associated with NSGI with a higher risk for those exposed for >3 months. As the clinical implications of NSGI are not known, judicious use of PPIs is needed. Prospective studies are required to confirm and to determine the etiologic factors (i.e., alteration of the gastric pH, serum gastrin) that may be related with the presence of NGSI.