Effect of Xingnao Zaizao Capsule on Formaldehyde-induced Memory Impairment in Mice

  Objective: To investigate the effect of Xingnao Zaizao Capsule on memory impairment in mice induced by formaldehyde and its mechanism.

  Methods: SPF grade KM mice were randomly divided into 5 groups: blank control group, solvent control group and low, medium and high dose groups, each with 14 mice. The 4 groups except the blank control group were exposed to formaldehyde. The poisoning was carried out in the poison device for 14 days. The learning and memory ability of each group of mice was tested by avoiding dark experiments; the activity of nitric oxide synthase (NOS) and superoxide dismutase (SOD) in brain tissue was measured by biochemical methods. Malondialdehyde (MDA) level; hematoxylin-eosin staining was used to observe the number and morphological and structural changes of pyramidal cells in the CA1 region of the mouse hippocampus.

  Results: Compared with the blank control group, mice in the solvent control group shortened the dark avoidance latency (P<0.01), increased the number of errors (P <0.01), decreased the activity of NOS and SOD in brain tissue (P <0.05), and increased the level of MDA (P <0.01), the number of pyramidal cells in the CA1 region of the hippocampus was reduced, the arrangement was sparse and disordered, and the shape was irregular. Compared with the solvent control group, the incubation period of the mice in the medium and high dose groups was prolonged (P <0.05), and the activities of NOS and SOD were both Increased (P <0.01), the number of errors in the low, medium and high dose groups decreased (P <0.05), and the MDA level decreased (P <0.01). Pyramidal cells in the hippocampus CA1 of the low and medium dose groups The number of layers increased slightly, and the pyramidal cells in the CA1 region of the hippocampus in the high-dose group were clearly layered, arranged tightly, and the number was significantly increased.

  Conclusion: Xingnao Zaizao Capsule can improve the memory impairment of mice caused by formaldehyde, and its mechanism may be related to its anti-oxidative damage and increasing the number of pyramidal cells in hippocampal CA1 area.