Abstract: Objective To investigate the effects of Chinese propolis on gastric mucosa in Helicobacter pylori (Hp) infected Mongolian gerbils. Methods Fifteen 5-week-old Mongolian gerbils were randomly divided to three groups: control group , infection group, and propolis treatment group.The first two groups were inoculated with 0.5 ml of Hp (10⁹ cfu/ml) by intragastric administration(i.g) for 3 times after 24 h fasting while control group was taken broth by i.g . 4 weeks after the first infection , i.g was repeated once every 5 days.At the 16^th week, the gerbils were inoculated with 0.5 ml of Hp (10⁹ cfu/ml) by i.g for consecutive 5 days to enhance infection. Gerbils in the propolis group were inoculated with propolis by i.g at the 22^th and 24^th week after the first infection, while the other two groups were inoculated with sterile saline in the same way. All the gerbils were sacrificed at the 27^th week. The liver, kidney and spleen were removed to measure the organ coefficient. Gastric mucosa was removed to determine the concentration of Hp and for pathological observation. Results Compared with the control, the infection group exhibited a lower serum IL-8 level (P<0.05), while the propolis group significantly elevated the serum IL-8 level compared with the infection group (P<0.01); the organ coefficient of liver, kidney and spleen were not significant among groups (P>0.05); the concentration of Hp in the propolis group (2.46±1.72 cfu/mg) was significantly lower (P<0.05) than that in the infection group (10.75±6.88×10²cfu/mg) (P<0.05); histological examination showed more serious mucosal inflammation in the the infection group. Conclusion The Propolis may inhibit the growth of Hp in the stomach of gerbils, and enhance anti-inflammatory ability in Hp-infected gerbils. Chinese propolis may play a role in mucosal repair and organ protection.

Key words: Propolis, Helicobacter pylori(Hp), Mongolian gerbil, Gastric mucosa