Protective Effects Of Tiaoxinfang On Cerebral Ischemia Reperfusion In Mice

Senile dementia includes Alzheimer’s disease (AD) and vascular dementia (VD). As the population aging is increasing in the world, the incidence of dementia is rising, especially in vascular dementia. Because of cerebral ischemia reperfusion, vascular dementia with high mortality and morbidity rate is becoming a serious problem which needs to solve urgently in life scientific research.Chinese traditional medicines, tiaoxinfang is made of codonopsis pilosula, cassia twig, tuckahoe, calamus, polygala and licorice. Previous researches showed that tiaoxinfang had many pharmacological effects on the improvement of learning and memory, antioxidant, and enhancing the activity of the cholinesterase. As the effect of tiaoxinfang was mainly concentrated on the cardiac and cerebral vascular, by improved Himori method to prepare the exprimental model of cerebral ischemia reperfusion, the therapeutic effect of tiaoxinfang on vascular dementia disease and its mechanism for the treatment of vascular dementia were studied.70mice were divided into seven groups randomly:normal control group, sham-operated group, cerebral ischemia reperfusion model control group, piracetam group and tiaoxinfang groups (40,20,10g·kg-1). The ethological experiments on learning and memory were used to observe the protective effects of tiaoxinfang on the memory impairment in mice of cerebral ischemia reperfusion. By determination of survival time in beheaded hypoxia mice and brain index, the pharmacodynamics effects of tiaoxinfang were observed. The activities of GSH-Px, SOD and the contents of MDA in brain, liver and heart tissues, the activities of NO, NOS, MAO-B, CAT in brain and liver tissues, the activities of LF and AChE in brain tissues were determined to demonstrate the effects on oxidative related enzymes’ activity and metabolites’ content of tiaoxinfang. By high performance liquid chromatography (HPLC), the tissue distribution’s differences of lobetyolin were acquired.1Pharmacodynamics experiments of tiaoxinfang1.1Effect on learning and memory of mice with cerebral ischemia reperfusionResults showed that cerebral ischemia could cause significant memory impairment in mice (P<0.05). Compared with the model group, piracetam group and tiaoxinfang groups (40,20,10g·kg-1) could improve the impairments of memory with cerebral ischemia reperfusion (P<0.05, P<0.01), and the results were related to the dose:in step-through test, the latency had an extended tendency, and the number of entry times was significantly reduced (P<0.05, P<0.01); In exploratory test, tiaoxinfang could shorten time of entering darkroom, time of climbing height and time of entering bright room, and increase number of climbing height (P<0.05, P<0.01); In platform test, the latency and the number of error times were significantly decreased (P<0.05, P<0.01).1.2Effect on hypoxia tolerance of mice with cerebral ischemia reperfusionResults showed that cerebral ischemia-reperfusion injury could shorten the survival time of beheaded hypoxia and decreased the number of mouth open and brain index (P<0.05). Compared with the model group, piracetam group and tiaoxinfang groups (40,20,10g·kg-1) could prolong the survival time of beheaded hypoxia and increased the number of mouth open and brain index (P<0.05, P<0.01), and the results were related to the dose.1.3Effect on oxidative related enzymes’ activity and metabolites’ content in tissues Results showed that cerebral ischemia-reperfusion injury could lower the levels of GSH-Px, SOD and increase the contents of MDA in brain, liver and heart tissues (P<0.05), improve the levels of NO, NOS, MAO-B, lower the levels of CAT in brain and liver tissues (P<0.05) and increase the activities of LF and AChE in brain tissues (P<0.05). Compared with the model group, piracetam group and tiaoxinfang groups (40,20,10g·kg-1) could improve the levels of oxidative related enzymes’activity and metabolites’ content (P<0.05, P<0.01), and improve the cerebral ischemia-reperfusion injury. All the effects were related to the dose.2Tissue distribution of lobetyolinResults showed that, the order of lobetyolin in mice’s tissues by HPLC as follows:blood> liver> heart> brain> spleen> lung> kidney, the best formulation was tiaoxinfang group (40g-kg-1), and the results were related to the dose.All the results implied that tiaoxinfang could lower the contents of MDA, LF and the activities of NO, NOS, MAO-B, AChE, increase the activities of CAT, GSH-Px, SOD, and enhance the effect of hypoxia tolerance. The effect of tiaoxinfang was best in group (40g·kg-1). It is expected clinically to treat ischemic cerebral vascular disease early.