Functional heartburn, nonerosive reflux disease, and reflux esophagitis are all distinct conditions—A debate: Con

Intranasal Surface-Modified Mosapride Citrate-Loaded Nanostructured Lipid Carriers (MOS-SMNLCs) for Treatment of Reflux Diseases: In vitro Optimization, Pharmacodynamics, and Pharmacokinetic Studies

Gastroesophageal reflux disease (GERD) is an esophageal injury occurred when the stomach contents reflux abnormally into the esophagus. GERD complications include esophageal adenocarcinoma. Mosapride (MOS) is a safe prokinetic agent potentially used to treat GERD. Yet, its low solubility and bioavailability due to extensive first-pass metabolism limits its applications. This study aimed to formulate MOS nanostructured lipid carriers (MOS-NLCs) via the intranasal route to improve its bioavailability. Melt-emulsification low temperature-solidification technique using 2³ full factorial design was adopted to formulate MOS-NLCs. Eight formulae were prepared and assessed in terms of entrapment efficiency (%EE), particle size, and in vitro release. Glycerol addition significantly reduced the particle sizes and improved %EE and %drug released. Surface modification using chitosan was applied. The optimized MOS surface-modified nanostructured lipid carriers (MOS-SMNLCs-F7)(stearic acid, 4% glycerol, 0.5% LuterolF127, 0.5% chitosan) showed low particle size 413.8 nm ± 11.46 nm and high %EE 90.19% ± 0.06% and a threefold increase in permeation of MOS with respect to the drug suspension. MOS-SMNLCs (F7) was also evaluated for its bioavailability compared with drug suspension and commercial product. Statistical analysis revealed a significant increase in gastric emptying rate to be 21.54 ± 1.88 contractions/min compared with10.02 ± 0.62 contractions/min and 8.9 ± 0.72 contractions/min for drug suspension and oral marketed product respectively. Pharmacokinetic studies showed 2.44-fold rise in bioavailability as compared to MOS suspension and 4.54-fold as compared to the oral marketed product. In vitro/in vivo studies proven to level A correlation between in vitro permeation through sheep nasal mucosa and in vivo absorption. Therefore, MOS-SMNLCs could be considered a step forward towards enhancing the clinical efficacy of Mosapride.

Role of tight junction proteins in gastroesophageal reflux disease

BACKGROUND

Gastroesophageal reflux disease (GERD) is associated with impaired epithelial barrier function that is regulated by cell-cell contacts. The aim of the study was to investigate the expression pattern of selected components involved in the formation of tight junctions in relation to GERD.

METHODS

Eighty-four patients with GERD-related symptoms with endoscopic signs (erosive: n = 47) or without them (non-erosive: n = 37) as well as 26 patients lacking GERD-specific symptoms as controls were included. Endoscopic and histological characterization of esophagitis was performed according to the Los Angeles and adapted Ismeil-Beigi criteria, respectively. Mucosal biopsies from distal esophagus were taken for analysis by histopathology, immunohistochemistry and quantitative reverse-transcription polymerase chain reaction (RT-PCR) of five genes encoding tight junction components [Occludin, Claudin-1, -2, Zona occludens (ZO-1, -2)].

RESULTS

Histopathology confirmed GERD-specific alterations as dilated intercellular spaces in the esophageal mucosa of patients with GERD compared to controls (P < 0.05). Claudin-1 and -2 were 2- to 6-fold upregulation on transcript (P < 0.01) and in part on protein level (P < 0.015) in GERD, while subgroup analysis of revealed this upregulation for ERD only. In both erosive and non-erosive reflux disease, expression levels of Occludin and ZO-1,-2 were not significantly affected. Notably, the induced expression of both claudins did not correlate with histopathological parameters (basal cell hyperplasia, dilated intercellular spaces) in patients with GERD.

CONCLUSIONS

Taken together, the missing correlation between the expression of tight junction-related components and histomorphological GERD-specific alterations does not support a major role of the five proteins studied in the pathogenesis of GERD.

Randomised clinical trial: sustained response to PPI treatment of symptoms resembling functional dyspepsia and irritable bowel syndrome in patients suffering from an overlap with erosive gastro-oesophageal reflux disease

BACKGROUND

Gastro-oesophageal reflux disease (GERD), functional dyspepsia (FD) and irritable bowel syndrome (IBS) are highly prevalent gastrointestinal conditions with accumulating evidence of overlap in patients. Despite availability of a vast body of research related to individual disorders, major pharmacological breakthrough in treatment of the overlap condition is still lacking.

AIM

To assess sustainability of GERD healing and whether known beneficial effects of proton pump inhibitor treatment on GERD also extend to symptoms suggestive of FD and IBS.

METHODS

A total of 626 patients with reflux oesophagitis were treated with pantoprazole for up to 16 weeks depending on healing of GERD, followed by an observational phase of up to 6 months without treatment. Rates of patients suffering from GERD, FD or IBS were assessed at baseline, and at last visits of treatment and observational phase.

RESULTS

Rates of patients with reflux oesophagitis and concomitantly with reflux symptoms, FD or IBS were each significantly lower after pantoprazole treatment (P < 0.0001). While rates of patients with reflux signs or symptoms increased again during observational phase, rates of FD and IBS were maintained at the low level after cessation of medication (P < 0.0001).

CONCLUSIONS

Pantoprazole is efficacious in the treatment of patients suffering from signs and symptoms suggesting an overlap of GERD, FD and/or IBS, providing a sustained response post-treatment in FD and IBS symptom categories. Mechanisms underlying the beneficial effects of improvement in reflux oesophagitis on symptoms suggestive of FD or IBS still need to be determined.