EFFECT OF INULICIN ON EXPRESSIONS OF COX-2 AND INOS GENES IN THE HIPPOCAMPUS OF AΒ-INDUCED ALZHEIMER’S DISEASE MODEL RATS

NIU XIAO-HUA, CHEN HONG-YUAN

Chongqing Three Gorges Medical College, Chongqing Engineering Research Center of Antitumor Natural Drugs

Objective: To investigate the effect of inulicin on expressions of COX-2 and iNOS genes in the hippocampus of Aβ-induced Alzheimer’s disease (AD) model rats.

Methods: A total of 60 rats were randomly divided into three groups of 20 rats each based on their weight. Group 1 was the blank control, group 2 the model and group 3 the experimental. AD models were established by injecting Aβ 25~35 into the brain of the rats in the model and experimental groups respectively. In addition, the rats in the experimental group were administered inulicin via gavage, once a day. These three groups were maintained for 21 days. After the 21 days period, immunohistochemistry and Western blot were used for proving that the production of COX-2 and iNOS proteins occured in the hippocampus of the rats, and RT- PCR was used to amplify the levels of COX-2 and iNOS mRNA molecules.

Results: The transcription of the mRNA molecules, and their translation into proteins, of COX-2 and iNOS in the hippocampus of the rats in the model group were significantly greater (p < 0.05) than those of the blank control group. The transcription of the mRNA molecules, and their translation into proteins, of COX-2 and iNOS in the hippocampus of the rats in the experimental group administered inulicin were significantly lower than those of the model group (p < 0.05).

Conclusion: Inulicin inhibits the expressions of COX-2 and iNOS genes in the hippocampus of Aβ-induced Alzheimer’s disease model rats. This suggests that inulicin plays anti -inflammatory role in the brain and this may be the mechanism by which it brings about amelioration in AD condition.