葛根素对溶血性磷脂酰胆碱诱导血管内皮损伤的保护作用及机制

Protective effect and mechanism of puerarin against lysophosphatidylcholine-induced vascular endothelial cell damage

目的:探讨葛根素对溶血性磷脂酰胆碱(LPC)所致血管内皮损伤的保护作用及机制。方法:家兔胸主动脉血管环分别与LPC(2.5～10 mg/L)和葛根素(0.25～1 g/L)单独孵育或共孵育,分别检测乙酰胆碱诱导的内皮依赖性舒张反应和硝普钠诱导的内皮非依赖性舒张反应,血管组织中一氧化氮和丙二醛含量,以及超氧化物歧化酶的活性。结果:分别用2.5～10 mg/LLPC孵育血管环30 min后,LPC呈剂量依赖性地抑制乙酰胆碱诱导的内皮依赖性舒张反应,降低了血管组织中一氧化氮含量和超氧化物歧化酶活性,增加了丙二醛含量。用0.25～1 g/L葛根素分别孵育血管环15 min,再与5 mg/LLPC共同孵育30 min,葛根素明显改善了LPC所致的内皮依赖性舒张功能的损害,升高了血管组织中一氧化氮的水平和超氧化物歧化酶的活性,降低了丙二醛的含量。结论:葛根素对LPC所致的血管内皮依赖性舒张功能的损伤具有明显的保护作用,其机制可能与其抗氧化有关。

Objective ：To explore the protective effect and mechanism of puerarin on damage of vascular endothelium induced by lysophosphatidylcholine（LPC）.Methods： The isolated rabbit thoracic aortic rings were incubated with LPC（2.5～10 mg/L）in absence or presence of puerarin（0.25 ～ 1 g/L）.The vascular endothelial-dependent relaxation and the content of nitric oxide（NO） and malonaldehyde（MDA）and the activity of superoxide dismutase（SOD）in the isolated thoracic aorta rings were measured.Results： Exposure of aortic rings to LPC（2.5 ～ 10 mg/L） for 30 min induced a significant concentration-dependent inhibition of endothelium-dependent relaxation to acetylcholine.Pre-incubation of aortic rings with puerarin（0.25 ～ 1 g/L） for 15 min and then co-incubation of the rings with LPC（5 mg/L） for another 30 min significantly attenuated the inhibition of endothelium-dependent relaxation induced by LPC.LPC markedly decreased the activity of SOD and the level NO but significantly increased the content of MDA in vascular tissues.Puerarin（0.25 ～ 1 g/L） significantly increased the level of NO and the activity of SOD but significantly decreased the content of MDA in vascular tissues.Conclusion： Puerarin may protect endothelium from being damaged by LPC.The mechanism of puerarin may be related to its antioxidant defenses.