Antioxidative Stress Pathways of <i>Amorphophallus oncophyllus</i> Tuber Extract as a Gastroprotector Against Indomethacin‐Induced Rat Gastric Ulcers

Gastric ulcers can result from oxidative stress, which generates free radicals. Amorphophallus oncophyllus ( A. oncophyllus ) has been reported to possess strong antioxidant activity. This study aims to evaluate the antioxidative stress potential of A. oncophyllus tuber extract in preventing indomethacin‐induced gastric ulcers in rats. In this study, 40 male rats were divided into five groups. The negative control group received 0.5% carboxymethyl cellulose (CMC) solvent, while the positive control group was given a single dose of indomethacin at 50 mg/kg BW. The remaining three groups were designated as treatment groups, where rats were administered A. oncophyllus tuber extract orally at doses of 100, 200, and 400 mg/kg BW, once daily for 14 days. On the 14th day, the treatment groups received a single dose of indomethacin at 40 mg/kg BW, 1 hour after administering the A. oncophyllus tuber extract. Four hours following indomethacin administration, the rats were euthanized for further analysis. Gastric tissues were collected for histological analysis and quantification of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels. Phytochemical screening of A. oncophyllus tuber extracts showed the presence of saponins, flavonoids, alkaloids, phenolics, and tannins. Antioxidant activity was evaluated using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) test, which had an IC 50 value of 157.21 μg/mL. A single dose of indomethacin at 50 mg/kg BW caused the formation of hemorrhagic lesions in the gastric mucosa, elevated MDA levels, and decreased SOD and GPx levels and led to necrosis of gastric mucosal epithelial cells. In contrast, the administration of A. oncophyllus tuber extract at a dosage of 400 mg/kg BW showed significant improvements in gastric ulcers, including reduced MDA levels, increased SOD and GPx levels, and decreased necrosis of gastric mucosal epithelial cells compared to the positive control group. However, no significant effects were observed at dosages of 100 mg/kg BW and 200 mg/kg BW. In conclusion, the findings indicate that A. oncophyllus tuber extract possesses strong antioxidant activity and has the potential as a gastroprotective agent for mitigating indomethacin‐induced gastric ulcers in rats.