| Abstract:[Abstract] Objective: Study on the Effect of Lishukang Capsule on Learning and Memory Impairment in Mice with High Altitude Hypoxia Based on Keap1/Nrf2/HO-1 Signal Pathway.Methods： Sixty male Balb/C mice were randomly divided into normal control group, hypoxia model group, Rhodiola capsule group ：400mg/（kg.d）, low, medium and high dose groups of Lishukang capsule： 400mg/（kg.d）, 600mg/（kg.d）, 800mg/（kg.d）), with 10 mice in each group. The normal control group was fed at the local altitude (1500m) after 7 days of intragastric administration in each group, and the rest groups were fed at the low pressure and hypoxia animal experimental cabin to simulate the altitude of 7500m for hypoxia for 3 days. During this period, the normal control group and the hypoxia model group were given physiological saline once a day, and 1 hour after the last administration,Eight arm maze was used to test the spatial memory ability of mice under simulated high altitude hypoxia; HE staining was used to observe the morphological changes of hippocampus in mice; Western blot was used to detect the changes of protein content of Keap1/Nrf2/HO-1 signal pathway and apoptosis related protein in hippocampus of mice.Results: Compared with the normal control group, the spatial memory ability of mice in the hypoxia model group was significantly impaired (P<0.01); HE staining showed that hippocampal neurons in mice were seriously injured; the content of brain tissue Keap1 protein and apoptosis related protein Bax and Caspase-3 increased (P<0.01); the content of Nrf2, HO-1 and apoptosis related protein Bcl-2 decreased (P<0.01). Compared with the hypoxia model group, the error rate of mice in the high dose group of Lishukang capsule in the eight arm maze behavior experiment was significantly reduced (P<0.05, P<0.01); HE staining showed that the neurons were arranged orderly and the cell morphology was good; the content of Keap1 protein and apoptosis related protein Bax and Caspase-3 decreased (P<0.01); the content of Nrf2, HO-1 and apoptosis related protein Bcl-2 increased (P<0.01).Conciusion: High altitude hypoxia can lead to oxidative stress injury in mouse brain tissue and induce the expression of apoptosis related genes, thus aggravating the cognitive dysfunction of mice; Lishukang capsule can effectively improve the learning and memory impairment of mice caused by hypoxia, and its mechanism may be related to regulating the Keap1/Nrf2/HO-1 signal pathway and reducing apoptosis. |
