苦丁茶对高胆固醇脂血症小鼠血清多不饱和溶血磷脂酰胆碱的改善作用

目的:研究苦丁茶水提取物对高胆固醇脂血症小鼠血清中多不饱和溶血磷脂酰胆碱的改善作用。方法:采用LCQTOF-MS/MS和LC-QTRAP-MS/MS建立小鼠血清中多不饱和溶血磷脂的液质联用定性和定量分析方法;采用高脂饲料喂养30 d诱发小鼠高胆固醇脂血症模型;以5,10,15 g·kg^-1·d^-1(按生药材量计算)苦丁茶水提取物连续灌胃给药4周,观察高胆固醇脂血症小鼠血清总胆固醇、低密度脂蛋白胆固醇的变化;观察小鼠肝脏油红O染色后的病理切片;同时,利用上述建立的液-质联用分析方法检测给药后小鼠血清中多不饱和溶血磷脂酰胆碱相对含量的变化。结果:苦丁茶水提取物能够显著降低由高脂饲料诱发的胆固醇脂血症小鼠血清总胆固醇、低密度脂蛋白胆固醇;对小鼠肝脏的脂肪堆积具有明细的抑制作用;同时,与正常小鼠相比,模型小鼠血清中的多不饱和溶血磷脂酰胆碱的相对含量显著下降,而苦丁茶水提取物对该类脂质成分具有显著的回调作用。结论:苦丁茶水提取物对高胆固醇脂血症小鼠血清中多不饱和溶血磷脂的回调作用可能涉及苦丁茶降血脂的药效作用机制,值得深入研究。

Improving effects of water extract of Kuding tea on serum lysophosphatidylcholines of hypercholesterolemic mice

OBJECTIVE To investigate the improving effects of water extract of Kuding tea on serum lysophosphatidylcholines (Lyso-PC) of hypercholesterolemic mice.METHODS An effective and specific approach was developed for the qualitative and quantitative analysis of polyunsaturated Lyso-PCs in mice serum using LC-QTOF-MS/MS and LC-QTOF-MS/MS. The hypercholesterolemic mice were induced by a high fat diet for 30 days. The hypercholesterolemic mice were intragastrically administered with 5, 10, 15 g·kg^-1·d^-1 (raw materials) water extract of Kuding tea for 4 weeks. Changes of serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) were observed in the mice, the light microscopic photographs from mice liver sections stained with Oil Red O were investigated. Meanwhile, the polyunsaturated Lyso-PCs in the serum from hypercholesterolemic mice administered with Kuding tea were quantitatively determined by LC-QTRAP-MS/MS.RESULTS The water extract of Kuding tea significantly decreased the serum TC and LDL-C levels. Meanwhile, the liver fat accumulation was also obviously improver by the evidence of the photographs stained with Oil Red-O staining. In addition, the relative contents of serum polyunsaturated Lyso-PCs were significantly increased in hypercholesterolemic mice compared to that of normal. However, these lipid molecules changed towards normal after 4 weeks of treatment with Kuding tea.CONCLUSION The findings also give the evidence that the improved effects on serum polyunsaturated Lyso-PCs of hypercholesterolemic mice may involve in the mechanism of hypolipidemic effect of water extract from Kuding tea, which are worthy of further studies.