BACKGROUND: Previous studies have demonstrated that scorpion venom in the scorpion can inhibit epilepsy and apoptosis.However,it remains unclear whether ethanol extracts of scorpion (EES) exhibit similar effects.OBJEC...BACKGROUND: Previous studies have demonstrated that scorpion venom in the scorpion can inhibit epilepsy and apoptosis.However,it remains unclear whether ethanol extracts of scorpion (EES) exhibit similar effects.OBJECTIVE: To investigate the effects of EES on hippocampal apoptosis and caspase-3 expression,and to compare the effects on sodium valproate (positive control drug) in a rat model of status epilepticus induced by lithium chloride-pilocarpine.DESIGN,TIME AND SETTING: This randomized,controlled study was conducted at the Drug Research and Development Center,Kanghong Pharmaceuticals Group,and the Department of Pathology,Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital,China from May 2007 to April 2008.MATERIALS: EES were prepared by Huashen Pharmaceutical,China.Sodium valproate (Hunan Xiangzhong Pharmaceutical,China) and lithium chloride-pilocarpine (Sigma,USA) were also used in the present study.METHODS: From a total of 156 rats,six served as normal controls.The remaining rats were intraperitoneally injected with lithium chloride-pilocarpine to establish status epilepticus models,and then assigned to five groups (n = 30,respectively).Animals in each group were administered drugs at 15 minutes after epileptic seizure by gavage.i.e.in the normal control and model groups,rats were treated with 1 mL/0.1 kg saline.The sodium valproate group was administered 120 mg/kg/d sodium valproate.The low-,moderate-,and high-dose EES groups received treatments of 290,580,and 1 160 mg/kg/d EES.The dispensed concentration was 1 mL/0.1 kg.Rat seizure behavior was observed.If status epilepticus did not terminated after 1 hour,the rats were intraperitoneally administered atropine (1 mg/kg) and diazepam (10 mg/kg) to terminate seizure.These rats were continuously observed for 6 hours to ensure seizure termination.Then rats were treated with the above-mentioned drugs at 8: 00 am each day until sacrifice,which took place 4 hours after drug administration.MAIN OUTCOME MEASURES: Terminal dUTP nick end labeling (TUNEL)-positive cells and caspase-3 expression were,respectively,determined by TUNEL and immunohistochemistry at 6,24,48,and 72 hours,as well as 7 days,after status epilepticus.Behavioral changes were also measured.RESULTS: A few caspase-3-positive cells were observed.TUNEL-and caspase-3-positive cells were mainly visible in the hippocampal CA1 and CA3 regions 6 hours following status epilepticus in the model and drug intervention groups.The number of TUNEL-positive cells reached a peak at 48 hours following status epilepticus in the sodium valproate group,as well as the moderate-and high-dose EES groups,and number of TUNEL-positive cells reached a peak at 72 hours in the model and low-dose EES groups.The number of caspase-3-positive cells reached a peak at 48 hours in each group.Following treatment of sodium valproate and EES,the number of TUNEL-and caspase-3-positive cells significantly decreased compared with the model group at various time points (P < 0.05).The number of TUNEL-and caspase-3-positive cells was greatest in the low-dose EES group,followed by the moderate-and high-dose EES groups.The number of TUNEL-and caspase-3-positive cells was similar between the sodium valproate and high-dose EES groups.Epileptic seizure was significantly improved in the sodium valproate group,as well as the moderate-and high-dose EES groups,compared with the model group (P < 0.05 or P < 0.01).Treatment with sodium valproate and high-dose EES resulted in the best outcome,although the results were similar (P > 0.05).CONCLUSION: A dose of 1 160 mg/kg/d EES significantly inhibited status epilepticus.This outcome corresponded to a decreased number of apoptotic cells and caspase-3-positive cells,which was similar to sodium valproate.These results suggest that it is not necessary to extract a component from the scorpion for the treatment of epilepsy.The high dose of EES significantly inhibited epilepsy,which correlated with decreased hippocampal caspase-3 expression.展开更多
基金the National Natural Science Foundation of China,No.30740035the Tackle Key Program of Sichuan Province,No.05SG1672
文摘BACKGROUND: Previous studies have demonstrated that scorpion venom in the scorpion can inhibit epilepsy and apoptosis.However,it remains unclear whether ethanol extracts of scorpion (EES) exhibit similar effects.OBJECTIVE: To investigate the effects of EES on hippocampal apoptosis and caspase-3 expression,and to compare the effects on sodium valproate (positive control drug) in a rat model of status epilepticus induced by lithium chloride-pilocarpine.DESIGN,TIME AND SETTING: This randomized,controlled study was conducted at the Drug Research and Development Center,Kanghong Pharmaceuticals Group,and the Department of Pathology,Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital,China from May 2007 to April 2008.MATERIALS: EES were prepared by Huashen Pharmaceutical,China.Sodium valproate (Hunan Xiangzhong Pharmaceutical,China) and lithium chloride-pilocarpine (Sigma,USA) were also used in the present study.METHODS: From a total of 156 rats,six served as normal controls.The remaining rats were intraperitoneally injected with lithium chloride-pilocarpine to establish status epilepticus models,and then assigned to five groups (n = 30,respectively).Animals in each group were administered drugs at 15 minutes after epileptic seizure by gavage.i.e.in the normal control and model groups,rats were treated with 1 mL/0.1 kg saline.The sodium valproate group was administered 120 mg/kg/d sodium valproate.The low-,moderate-,and high-dose EES groups received treatments of 290,580,and 1 160 mg/kg/d EES.The dispensed concentration was 1 mL/0.1 kg.Rat seizure behavior was observed.If status epilepticus did not terminated after 1 hour,the rats were intraperitoneally administered atropine (1 mg/kg) and diazepam (10 mg/kg) to terminate seizure.These rats were continuously observed for 6 hours to ensure seizure termination.Then rats were treated with the above-mentioned drugs at 8: 00 am each day until sacrifice,which took place 4 hours after drug administration.MAIN OUTCOME MEASURES: Terminal dUTP nick end labeling (TUNEL)-positive cells and caspase-3 expression were,respectively,determined by TUNEL and immunohistochemistry at 6,24,48,and 72 hours,as well as 7 days,after status epilepticus.Behavioral changes were also measured.RESULTS: A few caspase-3-positive cells were observed.TUNEL-and caspase-3-positive cells were mainly visible in the hippocampal CA1 and CA3 regions 6 hours following status epilepticus in the model and drug intervention groups.The number of TUNEL-positive cells reached a peak at 48 hours following status epilepticus in the sodium valproate group,as well as the moderate-and high-dose EES groups,and number of TUNEL-positive cells reached a peak at 72 hours in the model and low-dose EES groups.The number of caspase-3-positive cells reached a peak at 48 hours in each group.Following treatment of sodium valproate and EES,the number of TUNEL-and caspase-3-positive cells significantly decreased compared with the model group at various time points (P < 0.05).The number of TUNEL-and caspase-3-positive cells was greatest in the low-dose EES group,followed by the moderate-and high-dose EES groups.The number of TUNEL-and caspase-3-positive cells was similar between the sodium valproate and high-dose EES groups.Epileptic seizure was significantly improved in the sodium valproate group,as well as the moderate-and high-dose EES groups,compared with the model group (P < 0.05 or P < 0.01).Treatment with sodium valproate and high-dose EES resulted in the best outcome,although the results were similar (P > 0.05).CONCLUSION: A dose of 1 160 mg/kg/d EES significantly inhibited status epilepticus.This outcome corresponded to a decreased number of apoptotic cells and caspase-3-positive cells,which was similar to sodium valproate.These results suggest that it is not necessary to extract a component from the scorpion for the treatment of epilepsy.The high dose of EES significantly inhibited epilepsy,which correlated with decreased hippocampal caspase-3 expression.
