银杏叶提取物对老龄大鼠心肌保护作用的研究

目的 探讨银杏叶提取物对老龄大鼠心肌的保护作用.方法 选择20月龄大鼠,分别给予银杏叶提取物(EGB)和非酶糖基化产物(AGEs)交联结裂解剂(ALT-711)灌胃,经16周治疗后,观察心肌内AGEs、血清内抗氧化活性物质超氧化物歧化酶(SOD)和谷胱甘肽过氧化酶(GSH-Px)及氧化代谢产物丙二醛(MDA)的含量,观察心肌细胞内线粒体DNA的缺失率及心肌超微结构的改变.结果 老龄对照组大鼠和成年对照组比较.心肌细胞间质增生、肿大,线粒体和内质网膜受损,心肌组织内AGEs含量减少分别为(33.5±1.3)AU/mgHYP和(18.1±1I 2)AU/mgHYP,t=7.18,P<0.05],血清中SOD和GSH-PX减少分别为(138.4±3.8)U/ml和(1283.8±28.8)U/ml、(227.7±13.8)U/ml和(2114.1±135.9)U/ml,t分别为-19.59和-18.79,均P<0.01],MDA增多分别为(6.7±0.6)mmol/ml与(4.1±1.O)mmol/ml,t=7.18,P<0.05],线粒体mtDNA缺失率增多(0.1805±0.0718)%和(0.0060±0.0001)%,t=6.98,P<0.01],EGB和ALT-711治疗组与老年对照组比较,心肌内AGEs产物减少(P<0.05).血清内SOD、GSH-PX抗氧化物质增多(P<0.05),血清氧化代谢产物MDA减少(P<0.05),mtDNA缺失率减少(P<0.01).结论 老龄大鼠心肌老化和非酶糖基化及氧化应激相关,EGB和ALT-711同样具有抑制非酶糖基化和抑制氧化应激的作用,通过对心肌内线粒体mtDNA缺失率的抑制,具有抗衰老作用.

Study on protective effect of the extract of ginkgo biloba on myocardial tissue in aged rat

Objective To investigate the protective effect of the extract of ginkgo biloba on myocardial tissue in aged rat.Methods The rats aged 20 months were given the extract of ginkgo biloba (EGB) and ALT-711 respectively by garage for 16 weeks.The aged controls and adult rats were infused with the same volume saline.The superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), malonyt diadehyde (MDA) in blood samples and advanced glycation end products (AGEs) in the myocardial tissue were measured .The myocardial histopathological changes under electron microscope and the mitochondrial DNA (mtDNA) deletion rate in myocardial cells were observed.Results Compared with the adult rats, the content of AGEs in myocardial cells in aged rats was significantly increased (33.5±1.3)AU/mgHYP us.(18.1±1.2)AU/mgHYP, t= 7.18,P<0.05] and the levels of SOD and GSH-PX in blood samples were decreased (138.4±3.8) U/mlvs.(227.7±13.8)U/ml, (1283.8±28.8) U/ml vs.(2114.1 ±135.9)U/ml, t=-19.59, -18.79;both P<0.01].The MDA level in the serum and mtDNA deletion rate in aged rats were higher than in adult rats(6.7±0.6) mmol/ml vs.(4.1±1.0) mmol/ml, (0.18054±0.0718) % vs.( 0.0060±0.0001)%, t=7.18,6.98;both P<0.05].Compared with the aged controls, the content of AGEs in myocardial cells, the level of MDA and mtDNA deletion rate were significantly decreased in EGB and ALT-711 treatment adults (all P<0.05).The SOD and GSH-PX in blood samples were increased in EGB and ALT-711 treatment adults (all P<0.05).Conclusions Nonenzymatic glycation may play an important role in myocardial aging, which may be amplified by oxidative stress.EGB and ALT-711 may have the same anti-aging effects by inhibiting nonenzymatic glycation and oxidative stress.