Effect of Gastrodiae Rhizoma Powder on Prevention of Dementia and Oxidation Resistance in Mice / 中国实验方剂学杂志

ABSTRACT

Objective:To study whether long-term administration of Gastrodiae Rhizoma powder can improve the learning and memory ability of APPswe/PSldE9 double transgenic (APP/PS1) Alzheimer' s disease(AD) model mice and delay the progress of AD whether these effects are related to the regulation of antioxidant stress pathway in Kelch-like epoxylopropylamine-related protein 1(Keap1)-nuclear factor E2 related factor 2 (Nrf2)/heme oxygenase(HO)-1, and further explore the neuroprotective mechanism of Gastrodiae Rhizoma powder and its role in the prevention and treatment of AD. Method:APP/PS1 double transgenic mice model, the mice consisted of five groups normal, normal administration group, model group, Gastrodiae Rhizoma powder prevention group, Gastrodiae Rhizoma powder treatment group.The mice in the normal administration group and the Gastrodiae Rhizoma powder prevention group were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) daily at the age of 8 weeks.The normal group and model group were given the same amount of normal saline at the same time, until 24 weeks old, Morris water maze was used to test the learning and memory ability of mice, and the treatment group was treated with Gastrodiae Rhizoma powder at 22 weeks old.The mice were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) every day for 2 weeks.The number of crossing platform, escape latency and platform residence time of mice were detected by Morris water maze from 24 weeks old to 24 weeks old.RNA, Real-time PCR was extracted from mouse hippocampus to detect the mRNA level of Nrf2, HO-1, Keap1, and Western blot was used to detect the expression of Nrf2, HO-1, Keap1 protein in mouse hippocampus. Result:Compared with normal group, the water maze test showed that the learning and memory ability of model group was lower than that of the model group (P<0.01), and the learning and memory ability of Gastrodiae Rhizoma powder prevention group and Gastrodiae Rhizoma powder treatment group was significantly higher than that of model group (P<0.01). Compared with normal group, the levels of Nrf2, HO-1 and protein in the hippocampus in model group decreased in varying degrees (P<0.05). Compared with model group, Gastrodiae Rhizoma powder prevented Nrf2, in the hippocampus of mice in model group.The level of HO-1 in mRNA and protein increased in different degrees (P<0.05, P<0.01). Levels of Nrf2, HO-1 mRNA in Gastrodiae Rhizoma powder treatment group was significantly higher than that in Gastrodiae Rhizoma powder group (P<0.05). There was no significant difference in the expression of Nrf2, HO-1 protein.There was no significant difference in mRNA and protein levels of Keap1 among different groups. Conclusion:Morris water maze test and other results showed that Gastrodiae Rhizoma powder could improve the learning and memory ability of APP/PS1 mice, and it may enhance the expression of downstream antioxidant genes by regulating Keap1-Nrf2/HO-1 pathway.And then improve the learning and memory ability of APP/PS1 mice.