PUERARIN PROMOTES VASCULAR REGENERATION AND NEURAL FUNCTION RECOVERY IN MCAO RATS BY UP-REGULATING THE EXPRESSION OF VASCULAR REGENERATION GENE

Qi Yu, Wangming Shen#

Traditional Chinese Medicine Hospital of Huangyan, Taizhou, PR China

Objective: To explore the mechanism of puerarin promoting vascular regeneration and neural function recovery in middle cerebral artery occlusion (MCAO) rats by up-regulating the expression of vascular regeneration gene.

Methods: All the rats were randomly divided into three groups: sham operation group, MCAO + normal saline group, MCAO + puerarin group (50 mg/kg), MCAO + puerarin group (100 mg/kg), MCAO + puerarin group (200 mg/kg). The right middle cerebral artery infarction model was established in rats of the puerarin group, and the rats without neurological deficit were eliminated. There were 24 rats in each group, and all the rats were given perfusion therapy for 1 d, 3 d, 7 d and 14 d. The rats in the sham operation group and the MCAO + normal saline group were injected with the same volume of normal saline once a day. The rats in the puerarin group were injected intraperitoneally with 50 mg/kg, 100 mg/kg and 200 mg/kg puerarin once a day. The rats in each group with fluorescence double staining were given an intraabdominal injection of 50 mg/kg Brdu twice daily. The neurological function of rats was evaluated by Bderson scoring standard. Real time PCR assay was used to detect the level of vascular endothelial growth factor (VEGF), Tie and angiogenin-1 (ANG-1) in each group. The effects of different doses of puerarin on newly differentiated endothelial cells in the ischemic area of the MCAO model rats were detected by immunofluorescence double staining.

Results: On the 1st day, 3rd day and 7th day, compared with the MCAO + normal saline group, the MCAO + 50 mg/kg puerarin group could significantly improve the neurological function of rats (P<0.05). On the 1st day, the effect of the MCAO + 100 mg/kg puerarin group could improve the neurological function (P<0.05), and there was no statistically significant difference between MCAO + 200 mg/kg puerarin group and MCAO + normal saline group (P>0.05). On the 14th day, there was no statistically significant difference between each puerarin group and the MCAO + normal saline group (P>0.05). On the 3rd, 7th and 14th days, the level of VEGF mRNA in the MCAO + 50 mg/kg puerarin group was significantly higher than that in the MCAO + normal saline group (P<0.05). On the 7th day and 14th day, the level of VEGF mRNA in the MCAO + 100 mg/kg puerarin group and the MCAO + 200 mg/kg puerarin group was remarkably higher than that in the MCAO + normal saline group (P<0.05). On the 7th day, Tie-2 level in the MCAO + 50 mg/kg puerarin group was obviously higher than that in the MCAO + normal saline group (P<0.01). On the 1st day, Ang-1 level in the MCAO + 200 mg/kg puerarin group was significantly higher than that in the MCAO + normal saline group (P<0.05). On the 14th day, the formation of new endothelial cells in the ischemic area of the MCAO + 50 mg/kg puerarin group was markedly higher than that of the MCAO + 100 mg/kg puerarin group, MCAO + 200 mg/kg puerarin group and MCAO + normal saline group (P<0.05).

Conclusion: Puerarin can promote vascular regeneration and neural function recovery in MCAO rats by up-regulating the expression of vascular regeneration gene, and MCAO + 50 mg/kg puerarin has the best effect.