ABSTRACT
Objective To investigate the action mechanism of Tianqi Yizhi Granules for Alzheimer disease. Methods Ninety SD rats were divided into sham-operation group, model group, positive medicine group, high, medium and low dosage of Tianqi Yizhi Granules groups. SD rats were injected with aggregated amyloid β1-42 protein (Aβ1-42) into their left ventricle to establish AD models. Treatment groups received gavage with Huperzine A or Tianqi Yizhi Granules. The sham-operation group and model group received gavage with the same volume of normal saline. The mitochondrial membrane potential, activity of complex Ⅰ, Ⅱ, Ⅲ and Ⅳ of mitochondrial respiratory chain, enzymatic activity of Na+-K+ATP, energy charge, and space leaning ability were detected. Results Compared with model group, Tianqi Yizhi Granules could significantly improve mitochondrial membrane potential, activity of complex Ⅰ, Ⅲ and Ⅳ of mitochondrial respiratory chain, enzymatic activity of Na+-K+ATP, space leaning ability, and energy metabolism of brain in AD rats. Conclusion Tianqi Yizhi Granules showed mitochondrial protective capacity, and could improve energy metabolism of brain in AD rats, and then improve AD rats’ space learning ability.
ABSTRACT
Objective To investigate the effects ofTianqi-Yizhi granules on oxidative stress in the brain tissue, and learning and memory in Alzheimer's disease model rats.Methods A total of 90 male SD rats were randomly divided into 6 groups by random number table method: sham operation group, model group, huperzine A group and groups of low-, medium- and high-doseTianqi-Yizhi granules, with 15 rats in each group. The AD rat model was prepared by the left lateral ventricle injection of amyloid-β1-42. One week after modeling, the rats in the groups of low-, medium- and high-doseTianqi-Yizhi granules received intragastric administration of 0.8, 1.6 and 3.2 g/kgTianqi-Yizhi granules, respectively; the rats in the huperzine A group received intragastric administration of 0.02 mg/kg huperzine A solution; and the rats in the sham operation and model groups received intragastric administration of equivalent volume of normal saline for 30 days. Learning and memory were evaluated using the dark avoidance test. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and malonaldehyde (MDA) level in the brain tissue were determined. ResultsIn comparison with the model group, the latencies to step into the dark chamber in the high- and medium-dose Tianqi-Yizhi granules groups were significantly longer (239.05 ± 48.42 s, 214.35 ± 74.52 svs. 97.39 ± 30.69 s; allP<0.01), the numbers of errors significantly decreased (1.93 ± 3.25, 2.27 ± 3.09vs. 6.62 ± 3.45; allP<0.05), the activities of SOD (177.27 ± 63.10 U/mg, 164.53 ± 72.58 U/mgvs.72.56±21.04 U/mg; all P<0.01) and GSH-Px (2 899.36 ± 362.27 U/g, 2 407.68 ± 472.14 U/gvs. 1 397.64 ± 442.17 U/g; allP<0.01), and MDA level (24.75 ± 9.94 nmol/mg, 27.74 ± 5.82 nmol/mgvs. 37.56 ± 17.23 nmol/mg; allP<0.01) in the brain tissue significantly increased. ConclusionTianqi-Yizhi granules could attenuate oxidative stress in the brain tissue, and improve learning and memory in AD rats.