[The effect of PNS on the content and activity of alpha-secretase in the brains of SAMP8 mice with alzheimer's disease].

OBJECTIVE

To explore the effects of PNS on the content and activity of alpha-secretase in the brains of SAMP8 mice with Alzheimer's disease.

METHODS

SAMP8 mice were randomly divided into four groups: PNS high-dosage group, PNS low-dosage group, huperzine A group and control group. The high-dosage group and low-dosage group were treated with 200 and 100 mg/kg PNS respectively per day and the huperzine A group was treated with 0.3 mg/kg huperzine A per day, all by intragastric administration for 8 consecutive weeks. The same volume of double distilled water was given to the control group. The activity of a-secretase was assayed by direct immunofluorescent method(DIF). Western blot was used to detect the content of alpha-secretase including ADAM9, ADAM10 and ADAM17 proteins.

RESULTS

The Relative Fluorescence Units (RFU) of PNS high-dosage and low-dosage groups were higher than that of control group (P < 0.01). The results of western blot showed that the level of ADAM9 protein expression in PNS high-dosage, low-dosage and huperzine A groups was significantly higher than that of control group (P < 0.05) while the levels of ADAM10 protein expression in PNS high-dosage, low-dosage and huperzine A groups was significantly lower than that of control group (P < 0.05), while level of ADAM17 of huperzine A group was higher than that of control group (P < 0.05).

CONCLUSION

PNS can increase activity of alpha-secretase in the brain of SAMP8 mouse via increasing the level of ADAM9 protein expression.