BRUNO SILVESTRINI1*, ROMANO SILVESTRI2, C.Y. CHENG3, MAURIZIO CERACCHI4, MATTEO INNOCENTI5
*Corresponding author
1. Fondazione di Noopolis, Rome, Italy
2. Laboratory affiliated with the Institute Pasteur Italy and Cenci Bolognetti Foundation,
Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
3. Population Council, Center for Biomedical Research, New York, USA
4. CMV-Stat Statistician, Rome, Italy
5. Fondazione di Noopolis, Rome, Italy

Abstract

This study was aimed at evaluating the barrier effect of collagen against hydrochloric acid.
It was investigated by coating a metallic surface with collagen, and measuring the drilling time against hydrochloric acid. Collagen was prepared as a semi-liquid solution, using its industrial derivative, known as gelatin or hydrolyzed collagen. This preparation displayed a consistent, and dose-dependent effect, which correlated with the molecular weight and amino acid composition. Partially hydrolyzed bovine collagen was about 5-fold more potent than hydrolyzed bovine collagen, while bovine collagen was half as active as fish collagen. The results provide compelling evidence that hydrolyzed fish collagen is a new compound potentially useful in the protection of mucosa against hydrochloric acid injury, serving as a novel biological barrier.

INTRODUCTION
Dyspepsia is the medical term for bad digestion. It consists of various symptoms in the upper abdomen, such as fullness, early satiation, bloating, heartburn, belching, nausea, vomiting, or pain (1-4). Dyspepsia is frequently caused by gastroesophageal reflux disease (GERD), gastritis, drugs or peptic ulcer. Less likely causes include cancer, pancreatic or hepatobiliary tract disease, motility disorders, infiltrative diseases of the stomach small intestine bacterial overgrowth (SIBO), irritable bowel syndrome (IBS) and others (5).
All forms of dyspepsia have in common two interconnected pathogenetic factors: an excessive secretion of hydrochloric acid by parietal cells and a reduction of the mucus that covers and protects the internal surface of the stomach (6). Ulcerative forms from non-steroidal anti-inflammatory drugs (NSAIDs) are a typical example of the second factor, resulting in part from the reduction of prostaglandin activity (7), in part from a contact action, which occurs locally on the gastrointestinal wall (8). Antacids and antisecretors, particularly the proton pump inhibitors (PPIs), have found to be important in the tre ...