The Protective Effect Of Braintone On Focal Cerebral Ischemia And Its Influence To Anoxic Signal Transduction Path In Rats

Aim: To investigate the neuroprotective effects of Braintone and the molecular mechanism in rat model of permanent focal cerebral ischemia.Methods: Permanent middle cerebral artery occlusion (pMCAO) model was induced by using intraluminal filament technique in rats. Braintone (87.5,175,350mg/kg) was administrated intragastrically for 7 days before ischemia. The neuroprotection of Braintone was analyzed by scoring neurological deficits, assessing brain infarction volume with 2,3,5-triphenyltetrazolium chloride (TTC) and determining the brain water content 24h after ischemia, and besides, the Regional Cerebral Blood Flow(rCBF) was detected just before and after pMCAO, Real time PCR was used to measure HIF-1αmRNA, INOSmRNA, VEGFmRNA levels, Immunohistochemistry and Western blot analysis was employed to determine alterations in HIF-1α,INOS, HO-1 in ischemic cortex.Results: Braintone (87.5,175,350mg/kg) reduced infarction volume in a dose-dependent manner (P< 0.01, P< 0.05). Braintone (87.5,175,350mg/kg) also significantly ameliorated motor behavior deficits, diminished the increase in brain water content and increased rCBF both before and after pMCAO (P< 0.01, P< 0.05). Real time PCR results showed that HIF-1αmRNA, INOSmRNA expression peaked at 3 hours after hypoxia, and the peak time of VEGFmRNA was at 6 hours after OGD(P <0.01), Braintont serum could significantly increased HIF-1αmRNA, INOSmRNA, VEGFmRNA expresstion(P <0.05, P <0.01). Immunofluorescence showed HIF-1αmRNA, INOSmRNA, HO-1 ?mainly expressed in the kytoplasm of HUVEC in control group, and the amount of HIF-1α, INOS, HO-1 positive cells significantly increased after OGD over 12 hours(P <0.01), and mainly expressed in the nucleus. Braintont serum could significantly increased HIF-1α, INOS, HO-1 expresstion, and promoted nuclear translocation(P <0.05, P <0.01). Besides, Western blot analysis revealed that: after hypoxia HIF-1α,ΙΝΟS expression significantly increased in HUVEC, and peaked at 12 hours after OGD(P<0.01), Braintone serum could significantly increased their content(P<0.05).Conclusion: The present research provide the original evidence that Braintone has neuroprotective activity on cerebral ischemic injury, and the effect may be mediated by activating HIF-1α/ INOS, HO-1, VEGF signal transduction pathway.