Upregulation of acid sensing ion channels is associated with esophageal hypersensitivity in GERD.

Proton pump inhibitors (PPIs) are the mainstay of therapy for gastroesophageal reflux disease (GERD) but up to 60% of patients have inadequate response to therapy. Acid sensing ion channels (ASICs) play important roles in nociception. This study aimed to investigate whether the increased expression of ASICs results in neuronal hyperexcitability in GERD. Esophageal biopsies were taken from GERD patients and healthy subjects to compare expression of ASIC1 and 3. Next, gene and protein expression of ASIC1 and 3 from esophageal mucosa and dorsal root ganglia (DRG) neurons were measured by qPCR, Western-blot and immunofluorescence in rodent models of reflux esophagitis (RE), non-erosive reflux disease (NERD), and sham operated groups. Excitability of DRG neurons in the GERD and sham groups were also tested by whole-cell patch-clamp recordings. We demonstrated that ASIC1 and 3 expression were significantly increased in patients with RE compared with healthy controls. This correlated positively with symptom severity of heartburn and regurgitation (p < .001). Next, ASIC1 and 3 gene and protein expression in rodent models of RE and NERD were similarly increased in esophageal mucosa as well as T3-T5 DRG neurons compared with sham operation. DRG neurons from RE animals showed hyperexcitability compared with sham group. However, intrathecal injection of ASIC specific inhibitors, PcTx1 and APTEx-2, as well as silencing ASIC1 and 3 genes with specific siRNAs prevented visceral hypersensitivity. Overall, upregulation of ASIC1 and 3 may lead to visceral hypersensitivity in RE and NERD and may be a potential therapeutic target for PPI non-responsive patients.

Esophageal Epithelial-Derived IL-33 Is Upregulated in Patients with Heartburn.

BACKGROUND: Interleukin-33 (IL-33) is a tissue-derived cytokine that is constitutively expressed in epithelial cells of tissues exposed to the environment and plays a role in sensing damage caused by inflammatory diseases. IL-33 acts as both a traditional cytokine and as a chromatin-associated nuclear factor in both innate and adaptive immunity. We recently showed that IL-33 in esophageal mucosa is upregulated in reflux esophagitis. However, IL-33 expression in patients with heartburn without mucosal injury and its relationship with intercellular space (ICS) have never been examined. We therefore examined the expression of cytokines and ICS in patients with heartburn. METHODS: The expression of IL-33 in the middle and distal esophageal mucosa of patients with heartburn without mucosal break and control samples was examined using real-time RT-PCR and immunofluorescence. The mRNA expression of IL-6, IL-8, MCP-1, and RANTES, and ICS was also analyzed. RESULTS: IL-33 expression and the mean ICS were significantly increased in the mucosa of patients with heartburn compared to that of the control. IL-33 and ICS were not different between the patients who were taking a PPI and those who were not. The upregulated IL-33 expression in the heartburn group was located in the nuclei of the basal cell layer. Although IL-6, IL-8, MCP-1 and RANTES levels were not different between control and patients with heartburn samples, IL-33 mRNA levels were still significantly correlated with IL-6, IL-8, or MCP-1 mRNA levels. CONCLUSION: Nuclear IL-33 is upregulated in patients with heartburn. Upregulated IL-33 in heartburn patients is related to the symptoms.

Expression of Proteinase-activated Receptor-2 in the Esophageal Mucosa of Gastroesophageal Reflux Disease Patients: A Histomorphologic and Immunohistochemical Study.

Data are limited regarding the role of proteinase-activated receptor-2 (PAR-2) in the esophageal mucosa in gastroesophageal reflux disease (GERD) patients. Our aim was to study PAR-2 expression and its relationship with different GERD-related clinical and pathologic parameters. Histomorphologic alterations in eosophageal mucosa in nonerosive reflux disease (NERD) and erosive reflux disease (ERD) were also, evaluated. Endoscopic biopsies of the esophageal mucosa were obtained from 94 GERD patients and 20 participants for histopathologic analysis and PAR-2 immunohistochemical staining. The present study demonstrated significantly higher PAR-2 expression in GERD patients compared with control, whereas no significant differences were seen between NERD and ERD groups. PAR-2 expression significantly correlated with histologic score (r=0.572, P<0.001) and severity of heartburn (r=0.541, P<0.001). PAR-2 expression was significantly associated with basal cell hyperplasia, and dilated intercellular spaces and inflammatory cell count (P<0.05). Histologic analysis revealed GERD-related histomorphologic alterations in the esophageal mucosa of GERD patients with significant differences (P<0.05) among groups. Total histologic score was significantly correlated with heartburn (r=0.299, P=0.025) and endoscopic severity (r=0.359, P=0.027) in NERD and ERD patients, respectively. Taken together, this study provides evidence for the major role of PAR-2 in the pathogenesis of GERD and GERD-associated mucosal alterations.

Hypersensitivity to acid is associated with impaired esophageal mucosal integrity in patients with gastroesophageal reflux disease with and without esophagitis.

Increased esophageal sensitivity and impaired mucosal integrity have both been described in patients with gastroesophageal reflux disease, but the relationship between hypersensitivity and mucosal integrity is unclear. The aim of the present study was to investigate acid sensitivity in patients with erosive and nonerosive reflux disease and control subjects to determine the relation with functional esophageal mucosal integrity changes as well as to investigate cellular mechanisms of impaired mucosal integrity in these patients. In this prospective experimental study, 12 patients with nonerosive reflux disease, 12 patients with esophagitis grade A or B, and 11 healthy control subjects underwent an acid perfusion test and upper endoscopy. Mucosal integrity was measured during endoscopy by electrical tissue impedance spectroscopy and biopsy specimens were analyzed in Ussing chambers for transepithelial electrical resistance, transepithelial permeability and gene expression of tight junction proteins and filaggrin. Patients with nonerosive reflux disease and esophagitis were more sensitive to acid perfusion compared with control subjects, having a shorter time to perception of heartburn and higher perceived intensity of heartburn. In reflux patients, enhanced acid sensitivity was associated with impairment of in vivo and vitro esophageal mucosal integrity. Mucosal integrity was significantly impaired in patients with esophagitis, displaying higher transepithelial permeability and lower extracellular impedance. Although no significant differences in the expression of tight junction proteins were found in biopsies among patient groups, mucosal integrity parameters in reflux patients correlated negatively with the expression of filaggrin. In conclusion, sensitivity to acid is enhanced in patients with gastroesophageal reflux disease, irrespective of the presence of erosions, and is associated with impaired esophageal mucosal integrity. Mucosal integrity of the esophagus is associated with the expression of filaggrin.

A case study of chiropractic management of pregnancy-related heartburn with postulated fetal epigenome implications.

OBJECTIVE: This case study reports on chiropractic care for pregnancy-related heartburn. The purpose of this article is to relate the benefit of chiropractic treatment for one individual, to contrast chiropractic management with the biomedical standard of care for pregnancy-related heartburn, and to point to potential epigenetic implications of the standard of care. CLINICAL FEATURES: A 32-year-old woman who was 24 weeks pregnant presented with persistent heartburn that she was treating with ranitidine (Zantac®) and calcium carbonate (Tums®) daily at the initiation of chiropractic care. INTERVENTION AND OUTCOME: Findings of the initial examination were thoracic intersegmental dysfunction and pain upon palpation of the diaphragm, with hypertonicity noted. Therapy localization was positive for reflexes associated with the esophagus and lower esophageal sphincter, suggesting spasms. Emotional components also were identified in association with the symptoms by the use of a mind-body therapy called NeuroEmotional Technique. The patient was treated by adjusting the thoracic spine, manually releasing the diaphragm spasms, and releasing the esophageal spasm with an activator (a small hand-held instrument that creates a percussive force). The patient was symptom-free and did not use medication after the fifth treatment. She was followed throughout the remainder of her pregnancy and was asymptomatic and required no further treatment. CONCLUSIONS: A larger study should investigate the effectiveness of chiropractic care for the treatment of pregnancy-related heartburn.

GABRA6 genetic polymorphism is associated with the risk of functional heartburn in Chinese.

BACKGROUND AND AIM: Polymorphisms of GABA(A)alpha6 (GABRA6)-1521 and IL-1beta-511 have been linked with susceptibility to stress and gastric acid secretion. The aim of this study was to assess psychiatric profiles and GABRA6 and IL-1beta genotypes in functional heartburn, an important esophageal reflux condition. METHODS: Psychological symptoms were assessed with a Brief Symptom Rating Scale and personality traits with a short-form Maudsley Personality Inventory. DNA from 452 healthy controls, 80 controls with neurosis, and 122 patients with functional heartburn was genotyped with PCR-RFLP technique. RESULTS: Symptom-scale parameters (except hostility) were significantly higher in patients with functional heartburn than in healthy controls; their neuroticism scores were also higher, but extroversion scores were lower. Distribution of GABRA6 genotypes in patients with functional heartburn showed more heterozygotes than among healthy controls and neurotic subjects, but distributions of IL-1beta genotypes were similar. Multiple logistic regression analysis showed GABRA6 heterozygosity was significantly associated with functional heartburn (odds ratio, 2.37; 95% confidence interval, 1.36-4.12; P < 0.01) even after adjustment for age, sex, Helicobacter pylori infection, General Symptom Index, and score of neuroticism. CONCLUSIONS: Chinese patients with certain psychiatric characteristics and GABRA6 heterozygosity are probably predisposed to functional heartburn, providing insight into this condition's psychopathology and genetics.

A study of swallowing difficulties in first degree relatives of patients with achalasia.

Of 167 patients with achalasia asked to provide details of swallowing difficulties among their first degree relatives, 159 completed the survey (95% response rate). One thousand and twelve first degree relatives were identified, and 14 were reported to have dysphagia including two with reported achalasia. Review of the case notes of these 14 relatives showed, however, that in none was achalasia confirmed. Heartburn affected 54 (5%) of the relatives, an incidence similar to that in the general population. These findings suggest that adult achalasia is not inherited in an autosomal recessive manner and that environmental factors during early life do not play an important aetiological part.