高低密度脂蛋白胆固醇对血小板免疫活化的影响及氟伐他汀的干预作用

Effects of High Low Density Lipoprotein Cholesterol on Platelets Immune Activity and Fluvastatin Intervention

目的观察高低密度脂蛋白胆固醇对体内及体外血小板膜PAC-1和CD40L表达的影响及氟伐他汀的干预作用并探讨可能的机制。方法以低密度脂蛋白胆固醇正常的健康对象为对照,通过流式细胞仪检测高低密度脂蛋白胆固醇患者服用氟伐他汀前后血小板膜PAC-1和CD40L表达阳性率变化;高低密度脂蛋白胆固醇血浆体外孵育健康血小板及低密度脂蛋白胆固醇直接孵育血小板并用氟伐他汀干预,流式细胞仪、RT-PCR及Westen blot-ting法检测血小板膜PAC-1和CD40L表达阳性率及血小板总CD40LmRNA及蛋白含量。结果高低密度脂蛋白胆固醇患者PAC-1和CD40L表达较对照组显著升高(9.47%±1.96%比5.73%±1.20%、3.04%±0.62%比1.87%±0.49%,P均<0.01),服用氟伐他汀一个月后随低密度脂蛋白胆固醇浓度降低,血小板膜PAC-1和CD40L表达阳性率均有不同程度降低(7.29%±1.35%比9.47%±1.96%、2.17%±0.53%比3.04%±0.62%,P均<0.01);体外高低密度脂蛋白胆固醇血浆较低密度脂蛋白胆固醇正常血浆更能促进血小板膜PAC-1和CD40L的表达(10.47%±1.39%比6.39%±1.23%、3.19%±0.73%比1.87%±0.47%,P均<0.01),氟伐他汀在体外未能显著抑制血小板膜PAC-1和CD40L表达(10.39%±1.41%比10.47%±1.39%、3.21%±0.69%比3.19%±0.73%,P均>0.05);单纯高低密度脂蛋白胆固醇在体外亦不能显著增加血小板膜PAC-1和CD40L的表达(3.99%±1.74%比3.87%±1.63%、0.83%±0.46%比0.77%±0.44%,P均>0.05),而高低密度脂蛋白胆固醇+ADP组血小板膜PAC-1、CD40L表达阳性率较ADP组显著增高(17.73%±2.09%比11.31%±2.12%、4.17%±0.71%比2.91%±0.69%,P<0.05),氟伐他汀的体外作用不显著;低密度脂蛋白胆固醇对血小板总CD40LmRNA和蛋白表达无明显影响,但高低密度脂蛋白胆固醇能够显著促进ADP活化血小板CD40L蛋白表达(1.63±0.19比1.40±0.21,P<0.05),氟伐他汀体外不能抑制这一作用。结论高低密度脂蛋白胆固醇在体内体外均能够促进血小板膜PAC-1和CD40L的表达,氟伐他汀在体内能抑制这一作用;低密度脂蛋白胆固醇本身不能够活化血小板免疫功能,但能够促进活化血小板,氟伐他汀体外无抑制血小板免疫活化的作用。

Aim To observe the effects of high low density lipoprotein cholesterol （LDLC） and fluvastatin on PAC-1 and CD40L expression of platelets in vitro and vivo and investigate its mechanism. Methods In vivo experiments,before and after treatment of fluvastatin for high LDLC patients,the CD40L and PAC-1 positive rate of platelets by flow cytometry were examined under the same conditions. The CD40L and PAC-1 expression of each group were compared. In vitro experiments,after the co-incubation of these chosed plasma or LDLC with the same healthy platelets and the interference with fluvastatin,the PAC-1 and CD40L positive rate of platelets were tested by flow cytometry and platelets total CD40L protein content by Western blotting and CD40L mRNA were examined under the same conditions in all objects. The PAC-1 and CD40L positive rate,the total CD40L content and CD40L mRNA of each group were compared respectively. Results Not only in vivo study but also in vitro study,the platelet PAC-1 and CD40L positive rate in high LDLC group were significant higher than in control group（P all〈0.01）. Followed the LDLC concentration decrease,the platelet PAC-1 and CD40L positive rate decreased after the treatment of fluvastatin in vivo,but in vitro study,the fluvastatin didn＇t affect the expression significantly. LDLC itself didn＇t affect the platelet PAC-1 and CD40L positive rate in