Long-term butylphthalide pretreatment attenuates ischemic brain injury in mice with permanent distal middle cerebral artery occlusion through Nrf2 pathway / 国际脑血管病杂志

ABSTRACT

Objective:To investigate the neuroprotective effect of long-term prophylactic use of buphthalein on mice with permanent distal middle cerebral artery occlusion and its relationship with the nuclear factor erysid 2 related factor 2 (Nrf2) pathway.Methods:Nrf2 + /+ wild-type and Nrf2 -/- knockout mice were randomly divided into control group (equal volume vegetable oil), low-dose butylphthalide group (20 mg/kg) and high-dose butylphthalide group (60 mg/kg), with 6 mice in each group. The drug was administered once a day by gavage for 1 month, and then a permanent middle cerebral artery occlusion model was induced by electrocoagulation. After the model was made, the drug was continued and the mice were sacrificed on the 10 th day. The modified Longa grading scale and the rotating rod test were used to evaluate neurological deficits on the 3 rd and 10 th day after the model was made. After the mice were sacrificed, the cerebral infarct volume was measured by triphenyltetrazolium chloride staining. The brain water content was measured by dry and wet weight method. The expression of Nrf2 pathway related factors, including Nrf2, heme oxygenase 1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1) were measured by quantitative real-time PCR and Western blotting. Results:On the 10 th day after modeling, compared with the Nrf2 -/- control group, the neurological deficit was significantly milder, the volume of cerebral infarction and brain water content were significantly smaller, and the mRNA and protein levels of Nrf2, HO-1 and NQO1 were significantly higher in the Nrf2 + /+ control group, and the differences were statistically significant ( P<0.05). For Nrf2 + /+ mice, compared with the control group, the cerebral infarct volume was significantly reduced ( P<0.05), the brain water content was significantly reduced ( P<0.05), and the neurological function recovery was significantly better ( P<0.05), and the levels of Nrf2, HO-1, and NQO1 mRNA and protein were significantly higher in the high-dose butylphthalide group (all P<0.05). For Nrf2 -/- mice, there were no significant differences in neurological function, cerebral infarction group volume, brain water content, Nrf2, HO-1, NQO1 mRNA and protein levels among the groups. Conclusion:Long-term butylphthalide pretreatment can significantly improve the neurological function, reduce cerebral infarction volume, reduce brain water content, and increase Nrf2, HO-1, NQO1 mRNA and protein expression levels in mice with permanent distal middle cerebral artery occlusion, suggesting butylphthalide may play a neuroprotective effect by up-regulating the expression of Nrf2 gene and its downstream antioxidant stress factors HO-1 and NQO1.