Indomethacin-induced gastric damage in rats and the protective effect of donkey milk

Introduction
Indomethacin is an anti-inflammatory drug with clearly known side effects on gastric mucosa. New treatment and side effect prevention methods are being studied. Donkey milk, as a nutritional support, has recently come into the spotlight with its anti-oxidant features, high antibody content and low allergenic properties. In this study, we investigated donkey milk’s possible protective effect against acute gastric mucosal damage by indomethacin.

Material and methods
Four groups, each composed of 8 rats, were created. Rats in the first and third groups were fed with standard rat chow, while those in the second and fourth groups were additionally fed with 25 mg/kg of donkey milk per day via nasogastric gavage. On the 11th day gastric mucosal damage was induced by oral administration of 30 mg/kg of indomethacin to the rats in groups 3 and 4. Six h later all rats were sacrificed and their stomachs were removed for macroscopic and microscopic evaluation as well as biochemical examination of glutathione (GSH) and malondialdehyde (MDA) levels. Tumor necrosis factor- (TNF-) expression in the gastric mucosa was evaluated immunohistochemically.

Results
In the donkey milk-indomethacin group, total area of erosion and degree of linear ulceration were significantly lower than in the standard food-indomethacin group (p < 0.05). Also, GSH levels were increased and MDA levels were decreased significantly in this group. Tumor necrosis factor-α expression was more prevalent and stronger in the gastritis group, while lower expression was observed in the donkey milk group.

Conclusions
Donkey milk was observed to have significant protective effects against gastric damage induced by indomethacin.