The aim of this research was to investigate the anti-apoptotic,
antioxidant and anti-inflammatory properties of
menthol against
ethanol-induced
gastric ulcers in rats. Wistar rats were orally treated with vehicle,
carbenoxolone (100 mg/kg) or
menthol (50 mg/kg) and then treated with
ethanol to induce
gastric ulcers. After
euthanasia, stomach samples were prepared for histological slides and biochemical analyses. Immunohistochemical analyses of the cytoprotective and anti-apoptotic heat-shock protein-70 (HSP-70) and the apoptotic
Bax protein were performed. The neutrophils were manually counted. The activity of the
myeloperoxidase (MPO) was measured. To determine the level of
antioxidant functions, the levels of
glutathione (GSH),
glutathione peroxidase (GSH-Px),
glutathione reductase (GR) and
superoxide dismutase (SOD) were measured using ELISA. The levels of the pro-inflammatory
cytokines tumor necrosis factor-α (TNF-α) and
interleukin-6 (IL-6) and the anti-inflammatory
cytokine interleukin-10 (IL-10) were assessed using ELISA kits. The
menthol treated group presented 92% gastroprotection compared to the vehicle-treated group. An increased immunolabeled area was observed for HSP-70, and a decreased immunolabeled area was observed for the
Bax protein in the
menthol treated group.
Menthol treatment induced a decrease in the activity of MPO and SOD, and the
protein levels of GSH, GSH-Px and GR were increased. There was also a decrease in the levels of TNF-α and
IL-6 and an increase in the level of
IL-10. In conclusion, oral treatment with
menthol displayed a gastroprotective activity through anti-apoptotic, antixidant and anti-inflammatory mechanisms.