Mechanisms of action of retinoids in gastrointestinal mucosal protection in animals, human healthy subjects and patients

Gyula Mózsik, Beáta Bódis, Mária Figler, Ágnes Király, Oszkár Karádi, Alajos Pár, György Rumi, Gábor Sütõ, Gyula Tóth, Áron Vincze

Research output: Article

17 Citations (Scopus)

Abstract

Retinoids prevent chemically induced gastric mucosal damage without inhibiting gastric acid secretion ("nutritional gastric cytoprotection"). The gastroprotective effects of retinoids do not depend on 1) vitamin A activity; 2) number of unsaturated double bonds; 3) the presence of a characteristic chemical structure of their terminal components; however, they depend on 1) intact vagal nerve and 2) adrenals in experimental animals. The gastric cytoprotective effect of retinoids produces a dose-dependent inhibition of ATP-transformation into ADP. It also increases the transformation of ATP into cAMP. Other features of these gastric cytoprotective effects of retinoids include: 1) The retinoid-induced gastric mucosal protection differs from that of PGs; 2) The cAMP is an intracellular signal in the development of gastric mucosal damage produced by chemicals (e.g., ethanol, HCl, indomethacin) and in the protection of gastric mucosa induced by retinoids (but not by PGs); 3) The gastric mucosal protection induced by retinoids and gastric mucosal permeability can be separated in time. The existence of gastric mucosal protection can be demonstrated in healthy persons (against indomethacin treatment), in patients with gastric ulcer (GU) and duodenal ulcer (DU) without any inhibition of gastric acid secretion. The serum levels of vitamin A and zeaxanthin were significantly decreased in patients with chronic gastrointestinal (GI) inflammatory diseases (e.g., terminal ileitis, ulcerative colitis), colorectal polyposis, and different (e.g., esophageal, gastric, pancreatic, hepatocellular and colorectal) malignant diseases. The serum levels of vitamin A provitamins were unchanged and their GI mucosal protective effects do not depend on vitamin A activity. Conclusions: 1) Abundant experimental and human observations clearly proved the defensive role of retinoids in the GI tract; 2) There is a correlation between the a) scavenger properties of retinoids vs. intact vagal nerve; b) scavenging properties vs. intact adrenals. 3) The GI mucosal protective effect of retinoids is correlated with biochemical changes in the GI mucosa.

Original languageEnglish
Pages (from-to)3103-3112
Number of pages10
JournalLife Sciences
Volume69
Issue number25-26
DOIs
Publication statusPublished - nov. 9 2001

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Pharmacology, Toxicology and Pharmaceutics(all)

Fingerprint Dive into the research topics of 'Mechanisms of action of retinoids in gastrointestinal mucosal protection in animals, human healthy subjects and patients'. Together they form a unique fingerprint.

  • Cite this