Gastric cytoprotective effects of vitamin A and other carotenoids.

The effects of vitamin A and some carotenoids (beta-carotene, beta-cryptoxanthin, zeaxanthin, lutein, capsorubin, capsanthin, capsanthol and lycopene) were studied (a) on the development of acute gastric mucosal lesions produced by topical application of 0.6 M HCl and (b) on gastric secretion in 4-h pylorus-ligated rats. It was found (a) that vitamin A, beta-carotene, beta-cryptoxanthin, zeaxanthin and lutein significantly inhibited the development of gastric mucosal lesions produced by 0.6 M HCl, while capsorubin, capsanthin, capsanthol and lycopene failed to prevent the development of such lesions; and (b) that vitamin A, beta-carotene, beta-cryptoxanthin, zeaxanthin and lutein, i.e., the carotenoids which exerted a cytoprotective effect, had no inhibitory effect on gastric acid secretion in 4-h pylorus-ligated rats. The possible relationship between chemical structure and gastric cytoprotection is discussed.