Apple polyphenols may protect stomachs from aspirin damage

Polyphenol extracts from apples may protect stomachs from ulcers and other complications associated with aspirin, suggests a new animal study from Italy.

Increases in hormone-like substances associated with inflammation and damage were attenuated by whether apple polyphenol extract, report the researchers in the British Journal of Nutrition .

If the results can be repeated in humans, it suggests a potential beneficial role for apple polyphenols in the growing market for supplements and functional foods associated with improved gastrointestinal health.

Stomach or peptic ulcers are a small hole or erosion in the gastrointestinal tract.

According to statistics from the US National Digestive Diseases Information Clearinghouse, peptic ulcers affect 14.5 million Americans.

Researchers from Universita Federico II, Naples and the Seconda Universita di Napoli investigated if apple polyphenol extract (APE) could reduce the aspirin-induced injury to lining of the stomach (gastric mucosa) in rats.

The animals were given a dose of apple polyphenols (0.0004 moles of catechins equivalents) prior to an oral dose of aspirin (200 mg/kg).

Lead research Giuseppe D'Argenio and co-workers report that the both macroscopic and microscopic injuries to the stomachs of the animals were decreased when the apple polyphenols were consumed prior to the oral aspirin dose.

Indeed, lesions were reduced by approximately 50 per cent, they said.

Levels of hormone-like substances associated with inflammation and damage such as cyclo-oxygenase-2 (COX-2), transforming growth factor-alpha (TGF-alpha) and heparin-binding epidermal-growth-factor-like growth factor (HB-EGF) mRNA were analysed by the researchers.

Selectively inhibiting the COX-2 enzyme blocks the formation of hormone-like substances called prostaglandins that cause the pain and inflammation responses.

D'Argenio and co-workers observed that aspirin led to increases in COX-2 and HB-EGF, but not of TGF-alpha, and that these increases were reduced by the apple polyphenols.

Moreover, the polyphenol extract counter-acted the increases in malondialdehyde (MDA) observed following aspirin consumption.

MDA is a reactive carbonyl compound and a well-established marker of oxidative stress "In conclusion, APE reduces aspirin-induced gastric injury independently of acid inhibition," wrote the researchers.

"We speculate that APE might be of therapeutic use in the prophylaxis of aspirin-related gastropathy," they conclude.

Polyphenols are receiving extensive research due to their potent antioxidant activity, their ability to mop-up harmful free radicals, and the associated health benefits.

Many have also been implicated in possible protection against diseases such as cancer and cardiovascular disease, while some have been reported to potentially offer protection from Alzheimer's.

Source: British Journal of Nutrition Published online ahead of print, doi:10.1017/S0007114508988747

"Apple polyphenol extracts prevent aspirin-induced damage to the rat gastric mucosa" Authors: G. D'Argenio, G. Mazzone, C. Tuccillo, I. Grandone, A.G. Gravina, G. Graziani, V. Fogliano, M. Romano