消化性溃疡相关基因研究进展

Effect of simulated weightlessness on the healing of experimental gastric ulcer in rats

AIM: To investigate the effect of simulated weightlessness on the healing of acetic acid-induced experimental gastric ulcer in rats and to explore the potential mechanisms involved.

METHODS: Thirty-two SD rats were randomly and equally divided into four groups: 7 d tail suspension group, 7 d control group,14 d tail suspension, and 14 d control group. Gastric ulcer was induced in rats with acetic acid. Tail suspension was used to simulate the weightlessness condition 3 days after ulcer induction. The gastric ulcer area was measured with a vernier caliper. The ultrastructure of regenerative mucosa was observed by electronic microscopy. Epidermal growth factor (EGF) level in gastric juice was determined by radioimmunoassay (RIA). The staging of ulcer healing was performed.

RESULTS: Compared to the 7 d control group, the ulcer area significantly increased (6.0 mm² ± 1.7 mm² vs 2.2 mm² ± 0.7 mm², t = 5.661, P < 0.01) and the stage of ulcer significantly decreased (χ² = 12.771, P < 0.01) in the 7d suspension group. Compared to the 14 d control group, the ulcer area and EGF level increased (3.0 mm² ± 1.2 mm² vs 1.1 mm² ± 0.4 mm², t = 4.233, P < 0.01; 0.155 ng/mL ± 0.052 ng/mL vs 0.103 ng/mL ± 0.019 ng/mL, t = 2.635, P < 0.05) in the 14 d suspension group. Compared to the 7 d suspension group, the ulcer area, EGF level and stage of ulcer significantly decreased (3.0 mm² ± 1.2 mm² vs 6.0 mm² ± 1.7 mm², t = 3.805, P < 0.01; 0.155 ng/mL ± 0.052 ng/mL vs 0.434 ng/mL ± 0.137 ng/mL, t = 5.657, P < 0.01; χ² = 12.953, P < 0.01) in the 14 d suspension group. The ultrastructural restoration and histological maturity of healed ulcer in the 7 d and 14 d suspension groups were inferior to those in the 7 d and 14 d control groups.

CONCLUSION: Simulated weightlessness may depress the structure of regenerative gastric mucosa, delay the healing of ulcer, and increase EGF level in gastric juice.

Yoghourt accelerates the recovery of gastric ulcer in rats

AIM: To investigate whether yoghourt accelerates the recovery of gastric ulcer in rats.

METHODS: Gastric ulcer was induced in rats by intraperitoneal injection of reserpine at a dose of 0.5 mL/kg. Rats with gastric ulcer were then divided into three groups: yoghourt group, milk group and sodium chloride group, which were intragastrically given yoghourt, milk and sodium chloride once (5 mL/kg) every other day, respectively. All animals were killed on day 7 after administration. The extent of mucosal lesions was evaluated based on Guth score. The levels of prostaglandin E2 (PGE2) and superoxide dismutase (SOD) in gastric mucosa were measured.

RESULTS: Punctiform erosion and hemorrhage were observed by naked eyes in rats of each group. Guth score was significantly lower in the yoghourt group than in the milk group (1.33 ± 0.577 vs 5.00 ± 1.323, P < 0.05) though there was no significant difference between the yoghourt group and sodium chloride group (P > 0.05). Epithelial cell necrosis and shedding and neutrophil infiltration of the propria lamina were observed by microscopy. The lesions in rats of the sodium chloride group were more severe than those in rats of the yoghourt group. The content of PGE2 in gastric mucosa was significantly higher in the yoghourt group than in the sodium chloride group (248.6 ± 43.73 vs 79.52 ± 31.74, P < 0.05) though no significant difference was observed between the yoghourt group and the milk group. The content of SOD in gastric mucosa was significantly lower in the yoghourt group than in the milk group (148.1 ± 2.18 vs 156.6 ± 1.66, P < 0.01), but showed no significant difference between the yoghourt group and the sodium chloride group.

CONCLUSION: Yoghourt exerts a positive effect on the recovery of gastric ulcer in rats possibly by increasing PGE2 content and decreasing SOD content.