Effect of the AMPK/GSK-3β/Nrf2 signaling pathway in cognitive impairment of aged mice induced by sevoflurane exposure
10.3760/cma.j.cn371468-20250719-00338
- VernacularTitle:AMPK/GSK-3β/Nrf2信号通路在七氟烷所致老龄小鼠认知功能损伤中的作用
- Author:
Shanshan HAN
1
;
Junjie LIANG
;
Yichen LIU
;
Dengxin ZHANG
Author Information
1. 江南大学附属妇产医院，无锡 214002
- Publication Type:Journal Article
- Keywords:
Cognitive dysfunction;
Sevoflurane;
Synaptic plasticity;
Oxidative stress;
Mitochondrial damage;
Mouse
- From:
Chinese Journal of Behavioral Medicine and Brain Science
2025;34(10):865-871
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the possible mechanism of cognitive impairment in aged mice induced by sevoflurane and the role of the AMPK/GSK-3β/Nrf2 signaling pathway.Methods:Eighteen 16-month-old SPF male C57BL/6J mice were randomly assigned to either a control group or a sevoflurane group according to the random number table method( n=9 per group). Mice in the sevoflurane group were exposed to 3% sevoflurane for 2 h every day for three consecutive days.Cognitive function of mice was assessed by novel object recognition test and Morris water maze test.Golgi staining was used to analyze dendritic spine morphology and density in the hippocampus. Mitochondrial ultrastructure was examined by transmission electron microscopy. Oxidative stress in hippocampal tissue was evaluated by reactive oxygen species(ROS) and glutathione(GSH) assay kits. Western blot was performed to measure synaptic plasticity-related proteins and proteins involved in the AMPK/GSK-3β/Nrf2 signaling pathway, while Nrf2 expression was assessed by immunofluorescence. Statistical analysis was performed using GraphPad Prism 7 software with independent-samples t-test or Mann-Whitney U test for between-group comparisons. Results:(1) The novel object recognition test showed that the recognition index in the sevoflurane group was significantly lower than that in the control group ( Z=-3.256, P=0.001).The escape latency in the Morris water maze test was longer ((49.50±10.14) s, (18.62±6.59) s; t=-7.221, P<0.001) and the number of platform crossings was lower ( Z=-2.673, P=0.008) in the sevoflurane group compared with those of the control group. (2) Results from Western blot and Golgi staining showed that the expression levels of hippocampal synapse-related proteins in the sevoflurane group, including PSD95 ((0.38±0.07), (1.00±0.21); t=4.885) and SYN1 ((0.30±0.10), (1.00±0.10); t=8.575), were lower than those in the control group, as well as the number of dendritic spines ((10.3±2.5), (20.0±1.0); t=6.183)(all P<0.05). (3) Transmission electron microscopy showed mitochondrial damage in the hippocampus of the sevoflurane group, and the expression level of ROS ((3.05±0.90), (0.97±0.16); t=-4.555, P=0.004) was significantly higher than that of the control group, while the expression level of GSH ((0.71±0.07), (1.00±0.09); t=5.396, P=0.002) was significantly lower than that of the control group.(4) Western blot and immunofluorescence demonstrated that hippocampal p-AMPK, p-GSK-3β (Ser9), and HO-1 expression levels in the sevoflurane group were significantly lower than those in the control group ( t=2.845, 7.087, 4.551, all P<0.05), and Nrf2 fluorescence intensity was also markedly reduced ( P<0.05). Conclusion:The cognitive impairment induced by sevoflurane in aged mice may be caused by mitochondrial damage, oxidative stress response and synaptic damage, which maybe associated with the inhibition of the AMPK/GSK-3β/Nrf2 signaling pathway.
