丹参保心茶调节 AMPK/OPA1 通路对冠心病合并认知功能障碍 模型大鼠的影响.

Objective To investigate the effect of Danshen Baoxin Cha (DBC) on a rat model of coronary heart disease combined with cognitive impairment. Methods Male Sprague-Dawley (SD) rats were randomly assigned to two groups: normal group and model group. Streptozotocin was injected into the bilateral ventricles of rats in the model group to establish cognitive impairment model, then isoproterenol hydrochloride was injected subcutaneously to model myocardial ischemia. Behavioral experiments were conducted to verify the success of the model of cognitive dysfunction. The rats of the model group were randomly divided into five groups: model control group, Tongxinluo Capsule group (TXL group, 1.6 g·kg-1), and low- (4 g·kg-1), medium- (8 g·kg-1), and high- (16 g·kg-1) dose DBC groups. These groups were received the respective treatments continuously for two weeks. Subsequently, the Y-maze, novel object recognition and Morris water maze experiment were employed to assess the learning and memory abilities of rats. A kit was utilized to quantify the level of oxidative stress in the brain and the adenosine triphosphate (ATP) content in the brain and mitochondria. Hematoxylin-eosin (HE) staining and Nissl staining were employed to observe the pathological changes of neurons in hippocampus CA1 region. Electron microscopy was utilized to observe the pathological changes of mitochondria in hippocampal CA1 region. The expression levels of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), glucose transporter type 4 (GLUT4), and optic atrophy 1 (OPA1) were quantified by real-time fluorescence quantitative polymerase chain reaction (PCR), and the expression of proteins related to the AMPK/OPA1 signaling pathway was determined by Western Blot analysis. Results Compared with the normal group, the spontaneous alternating reaction rate, the novel object recognition index, number of crossing the original platform, and distance ratio in the model group were obviously decreased (P＜0.01). Neuronal density in the CA1 region of the hippocampus was decreased, Nissl bodies were decreased, and nucleus consolidation was increased. The ATP level in mitochondria, and the levels of ATP, SOD, and GSH-PX in brain were significantly decreased (P＜0.05, P＜0.01), as well as the content of ROS and MDA were significantly increased (P＜0.05, P＜0.01). The mitochondria of hippocampus in CA1 region were swollen, with sparse and vacuolated cristae. The mRNA expression levels of GLUT4, PGC-1α, and OPA1 were significantly decreased (P＜0.01). The protein expression levels of GLUT4, SIRT1, PGC-1α and OPA1, and p-AMPK/ AMPK ratio were significantly decreased (P＜0.05, P＜0.01). Compared with the model group, the behavioral indexes of rats in the DBC groups were significantly improved (P＜0.05, P＜0.01), the number of neurons in the hippocampal CA1 area, Nissl bodies and nucleus consolidation were improved. The ATP level in mitochondria and the levels of ATP, SOD, and GSH-PX in brain were significantly increased (P＜0.05, P＜0.01). The levels of ROS and MDA were significantly decreased (P＜0.05, P＜0.01). The structure of mitochondrial cristae in hippocampal CA1 region were relatively intact. The mRNA expression levels of GLUT4, PGC-1α and OPA1 were increased (P＜0.05, P＜0.01), and the expression of proteins related to the AMPK/OPA1 signaling pathway was significantly increased (P＜0.05, P＜0.01). Conclusion DBC can enhance learning and memory abilities, reduce neuronal damage in a rat model of coronary heart disease combined with cognitive impairment. The mechanism may be related to the reduction of oxidative stress damage in the brain, the activation of the AMPK/OPA1 signaling pathway, and the restoration of energy levels. [ABSTRACT FROM AUTHOR]