Combination of angiotensin II receptor blockers promotes proton pump inhibitor-based healing of reflux esophagitis

Lansoprazole alleviates pressure overload-induced cardiac hypertrophy and heart failure in mice by blocking the activation of β-catenin

AIMS

Proton pump inhibitors (PPIs) are widely used in patients receiving percutaneous coronary intervention to prevent gastric bleeding, but whether PPIs are beneficial for the heart is controversial. Here, we investigated the effects of lansoprazole on cardiac hypertrophy and heart failure, as well as the underlying mechanisms.

METHODS AND RESULTS

Adult male C57 mice were subjected to transverse aortic constriction (TAC) or sham surgery and then were treated with lansoprazole or vehicle for 5 weeks. In addition, cultured neonatal rat ventricular cardiomyocytes and fibroblasts were exposed to angiotensin II in the presence or absence of lansoprazole. At 5 weeks after TAC, the heart weight/body weight ratio was lower in lansoprazole-treated mice than in untreated mice, as was the lung weight/body weight ratio, while left ventricular (LV) fractional shortening and the maximum and minimum rates of change of the LV pressure were higher in lansoprazole-treated mice, along with less cardiac fibrosis. In cultured cardiomyocytes, lansoprazole inhibited angiotensin II-induced protein synthesis and hypertrophy, as well as inhibiting proliferation of fibroblasts. Lansoprazole decreased myocardial levels of phosphorylated Akt, phosphorylated glycogen synthase kinase 3β, and active β-catenin in TAC mice and in angiotensin II-stimulated cardiomyocytes. After overexpression of active β-catenin or knockdown of H+/K+-ATPase α-subunit, lansoprazole still significantly attenuated myocyte hypertrophy.

CONCLUSION

Lansoprazole inhibits cardiac remodelling by suppressing activation of the Akt/GSK3β/β-catenin pathway independent of H+/K+-ATPase inhibition, and these findings may provide a novel insight into the pharmacological effects of PPIs with regard to alleviation of cardiac remodelling.

Angiotensin receptor blocker use and gastro-oesophageal cancer survival: a population-based cohort study

BACKGROUND

Angiotensin receptor blockers (ARBs; including candesartan, losartan, olmesartan and valsartan) are widely used to treat hypertension, heart failure and diabetic neuropathy. There is considerable pre-clinical evidence that ARBs can reduce cancer progression, particularly for gastric cancer. Despite this, epidemiological studies have yet to assess the impact of ARB use on gastro-oesophageal cancer survival.

AIM

To investigate the association between post-diagnosis ARB use and gastro-oesophageal cancer survival.

METHODS

We selected a cohort of patients with newly-diagnosed gastro-oesophageal cancer between 1998 and 2012 from English cancer registries. We linked to prescription and clinical records from the Clinical Practice Research Datalink, and to death records from the Office for National Statistics. We used time-dependant Cox-regression models to calculate hazard ratios (HRs) comparing gastro-oesophageal cancer-specific mortality between post-diagnosis ARB users and non-users, after adjusting for demographics, comorbidities and post-diagnosis aspirin or statin use.

RESULTS

Our cohort included 5124 gastro-oesophageal cancer patients, of which 360 used ARBs, and 3345 died due to their gastro-oesophageal cancer during follow-up. After adjustment, ARB users had moderately lower risk of gastro-oesophageal cancer mortality than the non-users (HR = 0.83, 95% CI 0.71-0.98). There was evidence of a dose-response relationship with the lowest HRs observed among patients receiving at least 2 years of prescriptions (HR = 0.42, 95% CI 0.25-0.72).

CONCLUSIONS

In this large population-based gastro-oesophageal cancer cohort, we found moderately reduced cancer-specific mortality among ARB users. However, confirmation in further independent epidemiological studies with sufficient staging information is required.

Association of medications for lifestyle-related diseases with reflux esophagitis

BACKGROUND

Because of a change in lifestyle, especially adoption of westernized eating habits, lifestyle-related diseases have become increasingly prevalent. The aim of this study was to investigate the association of medications for lifestyle-related diseases with reflux esophagitis (RE).

METHODS

We conducted a hospital-based, cross-sectional retrospective study of consecutive outpatients who received an upper gastrointestinal endoscopy in our department from February 2008 to November 2014, which was performed by one specialist who was a member of the Japan Gastroenterological Endoscopy Society. We investigated the patient profile, Helicobacter pylori (H. pylori) infection status, medications for lifestyle-related diseases (including calcium channel blockers, statins, and bisphosphonates), and upper gastrointestinal endoscopic findings (RE, hiatal hernia, Barrett's mucosa, and endoscopic gastric mucosal atrophy [EGA]). Patients with gastrectomy, peptic ulcer disease, gastric or esophageal malignant disease, and those who used proton pump inhibitors or histamine-2 receptor antagonists were excluded. We divided the subjects into a group without RE (RE(-)) and a RE (RE(+)) group as judged by endoscopy, and investigated the risk factors for RE.

RESULTS

Of 1,744 consecutive cases, 590 cases (300 males and 290 females; mean age 60.5±13.2 years) were eligible. RE(-) and RE(+) cases numbered 507 and 83, respectively. Bivariate analysis showed significant positive associations of RE with male sex, body mass index (BMI), calcium channel blockers, Barrett's mucosa, hiatal hernia and negative associations of RE with H. pylori positivity, EGA. Multivariate analysis showed significant positive associations of RE with BMI (odds ratio [OR]: 1.20, 95% confidence interval [95% CI]: 1.10-1.29), use of calcium channel blockers (OR: 2.12, 95% CI: 1.16-3.87), Barrett's mucosa (OR: 2.97, 95% CI: 01.64-5.38), hiatal hernia (OR: 3.13, 95% CI: 1.79-5.47) and negative associations of RE with H. pylori positivity (OR: 0.20, 95% CI: 0.07-0.57), use of statins (OR: 0.42, 95% CI: 0.18-0.96), and EGA (OR: 0.83, 95% CI: 0.70-0.98).

CONCLUSION

Calcium channel blockers were positively associated with RE and statins were negatively associated with RE, while bisphosphonates were not associated with RE.

The renin-angiotensin system in Barrett's esophagus

OBJECTIVE

Barrett's esophagus (BE) is a risk factor for esophageal adenocarcinoma. In addition to its classical endocrine character known for hemodynamic regulation, the renin-angiotensin system (RAS) can be associated with inflammation, wound healing, and cancer. The aim of this study was to explore a potential expression of the RAS in BE, with or without the presence of dysplasia.

MATERIAL AND METHODS

Biopsy material was prepared for western blotting and immunohistochemistry. Non-BE patients (controls) were compared with BE patients regarding RAS in the squamous epithelium. In the columnar BE mucosa, RAS expression was studied in patients with and without dysplasia. Key components of the 'classical' RAS were assessed: the angiotensin-converting enzyme (ACE) and the angiotensin II subtype 1 and 2 receptors (AT1R and AT2R).

RESULTS

The presence of RAS factors was confirmed in the esophageal mucosa of both control and BE patients. ACE protein expression was 48% lower (p = 0.001) whereas AT1R was 45% higher (p = 0.039) in the squamous epithelium of BE patients compared to epithelia from non-BE controls. In the metaplastic intestinal-like epithelium, AT1R expression was 37% higher in BE patients with confirmed dysplasia than in patients without dysplasia (p = 0.009). Immunohistochemistry showed an altered distribution of RAS proteins in BE patients with dysplasia.

CONCLUSIONS

The differential RAS expression observed may prove to be useful as a biomarker or a pharmaceutical target.

Association between metabolic syndrome and prevalence of gastroesophageal reflux disease in a health screening facility in Japan

BACKGROUND

Abdominal fat accumulation, which induces high intra-abdominal pressure that causes increase in the gastroesophageal pressure gradient and hiatal hernia, as well as obesity, has been shown to increase the prevalence of gastroesophageal reflux disease (GERD). This study was performed to clarify the association between metabolic syndrome and the prevalence of GERD.

METHODS

The study subjects were an adult population who visited a medical center for annual medical check-ups from April 2010 to March 2011. GERD was diagnosed by the presence of endoscopically proven reflux esophagitis, GERD symptoms (QUEST score ≥6), or current medical therapy for GERD. The presence of metabolic or pre-metabolic syndrome was diagnosed based on the Japanese criteria for metabolic syndrome.

RESULTS

Six hundred four (16.0 %) of 3775 study subjects were positively diagnosed with GERD, with the number of those with metabolic and pre-metabolic syndrome being 477 (12.6 %) and 384 (10.2 %), respectively. Multiple logistic regression analysis showed that male gender, presence of hiatal hernia, and metabolic or pre-metabolic syndrome, as well as absence of gastric mucosal atrophy, were significant predictive factors for the prevalence of GERD, as were visceral fat accumulation and untreated dyslipidemia. Untreated hypertension and untreated hyperglycemia were also considered to be positive risk factors. Subjects undergoing treatment for hypertension showed an increased risk of GERD, while those undergoing treatment for dyslipidemia and diabetes mellitus showed a decreased risk.

CONCLUSION

Metabolic syndrome is a reliable predictive factor for the prevalence of GERD, and medical therapy for metabolic syndrome may modify the risk of GERD occurrence.

The renin-angiotensin system in the esophageal mucosa of healthy subjects and patients with reflux disease

OBJECTIVE

Components of the renin-angiotensin system (RAS) were recently discovered in the esophagus, which could be of interest in relation to gastroesophageal reflux disease (GERD). The present study was undertaken to confirm and further investigate the expression of RAS in healthy and refluxed exposed human esophageal mucosae.

METHODS

Esophageal biopsies were obtained from healthy subjects (n = 34) and individuals with erosive reflux disease (ERD, n = 28). Evaluation of general morphology and histological signs of reflux as well as investigation of gene transcript, protein expression and localization of various RAS components using RT-PCR, ELISA, western blot and immunohistochemistry were performed. Physiological effects of the AT2R were investigated in Ussing chamber experiments.

RESULTS

The study confirmed histological signs of reflux in ERD and expression of ACE, AT1R, AT2R and CatD in all examined specimens. In addition, the main effector peptide AngII, the pro-hormone AGT, the Mas receptor and the angiotensin-forming enzymes renin, CMA, CatG and NEP were present. Individuals with reflux disease had higher transcription activity of ACE and AT1R, increased protein levels of AT2R and lower levels of MasR. AT2R stimulation increased the ion currents in healthy epithelium, whereas epithelium from individuals with reflux disease exhibited no significant response.

CONCLUSIONS

The study demonstrated that a local RAS is present in the human esophageal epithelium. Some RAS components were significantly altered in individuals diagnosed with ERD suggesting involvement in the pathophysiology of GERD.