1,6二磷酸果糖对慢性心肌缺血大鼠脑损伤的保护作用

Protective effects of 1,6-fructose-diphosphate against rat brain damage induced by chronic myocardial ischemia

目的:观察口服1,6二磷酸果糖对大剂量异丙肾上腺素所致慢性心肌缺血大鼠脑组织损伤的保护作用。方法:实验于2003-01/11在北京大学第一医院动物实验中心和北京市积水潭医院神经内科实验室进行。取雄性Wistar大鼠24只随机分为3组,每组8只:①异丙肾上腺素组:皮下注射异丙肾上腺素5mg/(kg·d),制成慢性心肌缺血模型,连续7d;同时给予生理盐水10mL/(kg·d)灌胃,连续21d。②1,6二磷酸果糖(FDP)组:造模同前,同时给予1,6二磷酸果糖10mL/(kg·d)灌胃,连续21d。③正常对照组:50μL/(kg·d)生理盐水皮下注射7d,同时给予生理盐水10mL/(kg·d)灌胃21d。硫代巴比妥酸法测定脑组织丙二醛含量;黄嘌呤氧化酶法测定超氧化物歧化酶活性;同时测定总抗氧化能力;并用光镜、电镜观察脑组织形态学改变。结果:24只大鼠进入结果分析。①丙二醛含量:异丙肾上腺素组、FDP组均高于正常对照组[(3.088±0.230),(2.265±0.349),(1.404±0.187)μmol/g,P<0.001],但FDP组低于异丙肾上腺素组(P<0.01)。②超氧化物歧化酶活性:异丙肾上腺素组、FDP组均低于正常对照组[(23.22±3.07),(39.70±3.44),(44.89±2.77)Nu/mg,P<0.001],但FDP组高于异丙肾上腺素组(P<0.01)。③总抗氧化能力:FDP组与正常对照组接近[(1.404±0.134),(1.474±0.062)u/mg,P>0.05],两组均异丙肾上腺素组[(0.581±0.114)u/mg,P<0.01]。④CA1区100μm内神经元数:异丙肾上腺素组、FDP组均少于正常对照组[(13.25±3.06),(32.25±4.33),(52.63±3.85)个,P<0.001],但FDP组多于异丙肾上腺素组(P<0.01)。结论:灌胃1,6二磷酸果糖可降低心肌缺血模型大鼠脑组织丙二醛含量,增加超氧化物歧化酶活性和总抗氧化能力,减轻脑组织病理的异常变化,提示1,6二磷酸果糖可预防、治疗慢性心肌缺血坏死所致的缺血性脑组织损伤,其神经保护机制可能与其抗氧化应激、抗自由基、增加细胞内能量、膜稳定等作用有关。

AIM：To observe the neuroprotective effect of 1,6-fructose-diphosphate （FDP） on rat cerebral tissues damage in the chronic myocardial ischemia model induced by large dose of isoproterenol （ISO）. METHODS： The experiment was performed in the Animal Experimental Center, First Affiliated Hospital of Peking University and Laboratory of Department of Neurology, Beijing Jishuitan Hospital from January 2003 to November 2003. Totally 24 male Wistar rats were randomly divided into 3 groups with 8 rats in each group ： ① Isoproterenol-treated group （ISO group） ：The rats were injected subcutaneously with isoproterenol 5 mg/kg per day for successive 7 days for preparing chronic myocardial ischemia models; At the same time, 10 mL/Ckg per day） normal saline were stomach-perfused for successive 21 days. ② FDP-treated group （FDP group）： Except injection of isoproterenol, the rats were treated by FDP 10 mL/kg per day perfused into stomachs for 21 days; ③ Normal control group： 50μL/kg per day normal saline was injected subcutaneously for 7 days and 10 mL/kg per day normal saline was stomach-perfused for 21 days at the same time. The content of malondialdehyde （MDA） was measured with thiobarbituric acid method and the activity of superoxide dismutase （SOD） was measured with xanthine oxidase method; mesnyhile total antioxidant capacity （TAC） was measured ; then, morphological change of cerebral tissue was observed under optical microscope and electron microscope. RESULT： Twenty-four rats entered the result analysis. ① The content of MDA in the ISO group and FDP group was both higher than that in the normal control group [（3.088±0.230）, （2.265±0.349）, （1.404±0.187）μmol/g,P 〈 0.001], but that in the FDP group was lower than that in the ISO group （P 〈 0.01 ）. ② Activity of SOD in the ISO group and FDP group was both lower than that in the normal control group [（23.22±3.07）, （39.70±3.44）, （44.89±2.77）Nu/mg,P 〈 0.001],while that in the FDP group was higher than that in the ISO group （P 〈 0.01 ）. ③ T-AOC in the FDP group was similar to that in the normal control group [（1.404±0.134）, （1.474 ±0.062）u/mg,P 〉 0.05], which was bpth different fiom that in the ISO group [（0.581±0.114）u/mg,P 〈 0.01].④ Neuron number in 100μm of CA1 area in the ISO group and FDP group was fewer than that in the normal control group [ （ 13.25±3.06 ）, （32.25±4.33）, （52.63±3.85）, P 〈 0.001 ], but that in the FDP group was more than that in the ISO group （P 〈 0.01 ）. CONCLUSION： Stomach-perfusing can decrease the content of MDA and decrease the activities of SOD and T-AOC of cerebral tissue in myocardial ischemia rat model so as to decrease the abnormal change of pathology of cerebral tissue, suggesting that 1,6-fructose-diphosphate can prevent and treat the cerebral tissue damage induced by chronic myocardial ischemic necrosis. Its neural protective mechanism might be related to antioxidant stress, anti-free radicals, increasing the cellular energy and stabilizing the biomembrane.