Résumé
OBJECTIVE To study the effect of Longsheng zhi capsule on lear ning and memory ability of vascular dementia model rats and explore its mechanism based on metabonomics. METHODS Totally 90 SD rats were randomly divided into sham operation group ,model group ,Dihydroergotoxin mesylate tablet group (positive control ,0.54 mg/kg),Longshengzhi capsule high-dose,medium-dose and low-dose groups (2.16,1.08 and 0.54 g/kg),with 15 rats in each group. In addition to sham operation group (only threading without ligation ),the vascular dementia model was prepared by permanent ligation of bilateral common carotid arteries in each group ,which was administered by gavage for 28 d. Morris water maze test was used to determine the learning and memory ability of rats ;hematoxylin eosin (HE)staining was used to observe the histopathological changes of hippocampus;the serum levels of superoxide dismutase (SOD),malondialdehyde(MDA)and glutathione peroxidase (GSH-Px) were detected ;the serum metabolic map was analyzed by ultra high performance liquid chromatography quadrupole time of flight tandem mass spectrometry (UPLC-Q-TOF/MS),the specific metabolites were screened by multivariate statistical analysis ,and the metabolic pathway was enriched and analyzed. RESULTS Morris water maze test showed that compared with model group ,the escape latency of rats in each administration group was significantly shortened ,the number of crossing the platform was significantly increased ,and the residence time in the target quadrant was significantly prolonged (P<0.01 or P< 0.05). The results of serum biochemical indexes showed that compared with model group , the s erum level of SOD increased significantly in Dihydroergotoxine mesylate tablet group and Longshengzhi capsule high-dose group ,the serum level of GSH-Px increased significantly while the MDA level decreased significantly in each administration group (P<0.05 or P<0.01). HE staining showed that Longshengzhi capsule could improve the histopathological damage of hippocampus in vascular dementia model rats. A total of 14 differential metabolites were screened and identified by UPLC-Q/TOF-MS and orthogonal partial least squares discriminant analysis model (VIP>1 and P<0.05). The results of metabolic pathway enrichment analysis showed that the metabolic pathways involved in vascular dementia in rats mainly included vitamin B 6 metabolism,fatty acid metabolism and steroid hormone biosynthesis. CONCLUSIONS Longshengzhi capsule can improve the learning and memory ability of rats caused by vascular dementia. Its effect may be related to improving the oxidative stress injury caused by lipid accumulation in the process of vascular dementia. The metabolic pathways involved mainly include vitamin B 6 metabolism,fatty acid metabolism and steroid hormone biosynthesis.