Study On The Protective Effect Of Hydroxy Safflower Yellow A On Animal Model Of Vascular Dementia

Objective:With the aging of society in our country,vascular dementia (VD) has gradually developed into one of the important diseases which affects the quality of life of the elderly,and cerebral ischemia (cerebral ischemia-reperfusion) is one of the most frequent causative factors.HSYA is one of the main active ingredient in safflower, a traditional Chinese medicine,it has good effect to improve blood circulation with removing blood stasis.This study preliminary explores the mechanism of the protective effect of HSYA on VD disease and provide theoretical basis for the clinical application of the drug to prevent VD.Methods:Experiment 1:We chose the mice as the model by the bilateral common carotid arteries clip method.After 3 days,the mice were conducted by step-through test and step-down test.We observed the change of psychiatric condition,the learning and memory abilities of all mice.After the tests,we removed the brain from its head of mice.Then we kept a record of the time when mouth breathing disappeared to evaluate the anti-hypoxia ability of mice.We used the colorimetric method to determine TP,SOD,MDA,NO,NOS,iNOS,LDH and LD in mice’brain tissue to evaluate the mice brain metabolism during the period of cerebral ischemia-reperfusion.We use the HE staining method to observe the pathological changes of brain tissue of mice which were made as the model.Experiment 2:We chose the mice as the model by permanent bilateral common carotid arteries ligation method.After 3 days,the mice were conducted by step-through test and step-down test too.We observed the change of psychiatric condition,the learning and memory abilities of all mice to evaluate the effect of the cerebral ischemia in mice.We use the RT-PCR to detect the effect of inflammatory factors like NF-κ B/p65,IL-1β,Caspase-12a,CHOP and mRNA expression in brain cells.We use the immunohistochemical staining to detect the expression of the above inflammatory factors in mice brain tissue.Results:In the experiment 1 we found that HSYA has a significant protective effect on ischemic injury of brain tissue, and can effectively improve the mental state and learning memory ability of cerebral ischemia reperfusion mice. HSYA can significantly improve brain tissue SOD and reduce MDA content, effectively reduce the lipid peroxidation damage on ischemia-reperfusion brain tissue, and enhance the ability of scavenging free radicals; reduce the accumulation of NO, decrease the activity of NOS and iNOS and the neurotoxicity damage of NO which is transformed by iNOS catalytc; significantly increasethe LDH activity, reduce the content of LD, so that can reduce the damage of cell membrane, reduce the degree of intracellular acidosis.In the experiment 2 we found that HSYA has a protective effect on nerve cells on focal cerebral ischemia in rats, HSYA can effectively control to reduce the mRNA gene’s expression of four inflammatory cytokine like NF-κB, IL-β, Caspase-12 and CHOP after cerebral ischemia in rats.Immunohistochemistry staining at the protein level also confirmed the inhibitory effect of HSYA on the four inflammatory factors, to display its anti-inflammatory effect. Mechanism of action may be mediated by down-regulating inflammatory signal transduction pathway in cerebral ischemia rat nuclear transcription factor kappa B to regulate pathway related factor IL-l;reducing the expression of Caspase-12 and CHOP, inhibiting the endoplasmic reticulum stress, thereby reducing the apoptosis of neural cells in rat brain.Conclusions:1) HSYA can obviously improve the learning and memory ability caused by vascular dementia, which has better protective effect on neurons, and the improvement and protection of the neurons showed a significant dependent relationship with dose;2) HSYA can reduce the accumulation of harmful metabolites in the brain tissue of ischemia reperfusion mice, enhance the ability of free radical scavenging, reduce the damage of lipid peroxidation and membrane damage, and reduce the degree of cellular acidosis;3) HSYA can have a significantly down regulation on four inflammatory cytokines mRNA transcription level of NF-κB, IL-1β, Caspase-12 and CHOP and protein expression, show that it has anti-inflammatory effects, inhibition of endoplasmic reticulum pathway and reduce the apoptosis of nerve cells.