AIM: To investigate the role of the hydrogen-rich water(HRW) in the prevention of aspirin-induced gastric mucosal injury in rats. METHODS: Forty male rats were allocated into four groups: normal control group, HRW group, aspirin group, and HRW plus aspirin group. The protective efficacy was tested by determining the gastric mucosal damage score. Malondialdehyde(MDA), superoxide dismutase(SOD), myeloperoxidase(MPO), interleukin(IL)-06 and tumor necrosis factor(TNF)-α in gastric tissues were evaluated. The serum levels of IL-1β and TNF-α were also detected. Histopathology of gastric tissues and localization of Cyclooxygenase 2(COX-2) were detected using hematoxylin and eosin staining and immunohistochemistry, respectively. RESULTS: Pretreatment with HRW obviously reduced aspirin-induced gastric damage scores(4.04 ± 0.492 vs 2.10 ± 0.437, P < 0.05). The oxidative stress levels of MDA and MPO in the gastric tissues increased significantly in the aspirin-treated group compared with the HRW group(2.43 ± 0.145 vs 1.79 ± 0.116 nmol/mg prot, P < 0.05 and 2.53 ± 0.238 vs 1.40 ± 0.208 U/g tissue, P < 0.05, respectively). HRW could obviously elevated the SOD levels in the gastric tissues(37.94 ± 8.44 vs 59.55 ± 9.02 nmol/mg prot, P < 0.05). Pretreatment with HRW significantly reduced IL-06 and TNF-α in the gastric tissues(46.65 ± 5.50 vs 32.15 ± 4.83 pg/mg, P < 0.05 and 1305.08 ± 101.23 vs 855.96 ± 93.22 pg/mg, P < 0.05), and IL-1β and TNF-α in the serum(505.38 ± 32.97 vs 343.37 ± 25.09 pg/mL, P < 0.05 and 264.53 ± 28.63 vs 114.96 ± 21.79 pg/mL, P < 0.05) compared to treatment with aspirin alone. HRW could significantly decrease the COX-2 expression in the gastric tissues(staining score: 8.4 ± 2.1 vs 2.9 ± 1.5, P < 0.05). CONCLUSION: HRW pretreatment alleviated the aspirin-induced gastric lesions by inhibiting the oxidative stress, inflammatory reaction and reducing the COX-2 in the gastric tissues. AIM: To investigate the role of the hydrogen-rich water (HRW) in the prevention of aspirin-induced gastric mucosal injury in rats. METHODS: Forty male rats were assigned into four groups: normal control group, HRW group, aspirin group, and Malondialdehyde (MDA), superoxide dismutase (SOD), myeloperoxidase (MPO), interleukin (IL) -06 and tumor necrosis factor (TNF) -α in The serum levels of IL-1β and TNF-α were also detected. Histopathology of gastric tissues and localization of Cyclooxygenase 2 (COX-2) were detected using hematoxylin and eosin staining and immunohistochemistry, respectively. RESULTS: Pretreatment with The oxidative stress levels of MDA and MPO in the gastric tissue increased significantly in the aspirin-treated group compared with the HRW group (2.43 ± 0.145 vs 1.79 ± 0.116 nmol / mg prot, P <0.05 and 2.53 ± 0.238 vs 1.40 ± 0.208 U / g tissue, P <0.05, respectively). HRW could obviously elevate the SOD levels in the gastric tissues ( 37.94 ± 8.44 vs 59.55 ± 9.02 nmol / mg prot, P <0.05). Pretreatment with HRW significantly reduced IL-06 and TNF-α in the gastric tissues (46.65 ± 5.50 vs 32.15 ± 4.83 pg / mg, P <0.05 and 1305.08 ± 101.23 vs 855.96 ± 93.22 pg / mg, P <0.05), and IL-1β and TNF-α in the serum (505.38 ± 32.97 vs 343.37 ± 25.09 pg / mL, P <0.05 and 264.53 ± 28.63 vs 114.96 ± 21.79 pg / mL, P <0.05) compared to treatment with aspirin alone. HRW significantly decreased the COX-2 expression in the gastric tissues (staining score: 8.4 ± 2.1 vs 2.9 ± 1.5, P < aspirin-induced gastric lesions by inhibiting the oxidative stress, inflammatory reaction and reducing the COX-2 in the gastric tissues.