普洱茶通过降低NF-κB活性促巨噬细胞凋亡改善动脉粥样硬化
Pu-erh tea’s anti-atherosclerosis mechanism by reducing the expression and activity of NF-κB and promoting macrophage apoptosis

摘要：目的 探讨普洱茶通过降低NF-κB表达及活性，促进巨噬细胞凋亡，发挥抗动脉粥样硬化的作用机制。方法 载脂蛋白E缺陷(ApoE-/-)小鼠喂饲普洱茶提取物8周和16周，观察主动脉斑块CD68阳性率及脂质斑块面积；细胞凋亡检测试剂盒检测巨噬细胞凋亡；实时定量PCR、Western blot检测主动脉斑块内及巨噬细胞内P65、IκB-β mRNA及蛋白表达；检测主动脉斑块内各炎症因子mRNA表达变化；电泳迁移率变化(EMSA)分析NF-κB DNA结合活性。结果 ApoE-/-小鼠经普洱茶提取物干预16周组脂质斑块面积分数及脂质成分面积较对照组明显降低(P均<0.05)。普洱茶提取物干预8周、16周组斑块内CD68阳性率较对照组降低(P<0.05)；主动脉斑块中巨噬细胞凋亡率增加(P<0.05)。普洱茶提取物干预8周、16周组巨噬细胞中p65 mRNA及蛋白表达较对照组降低(P<0.05)；16 周干预组IκB-β mRNA及蛋白表达降低(P<0.05)，主动脉组织中IL-6、IL-12和TNFα的相对表达水平分别较对照组下降(P均<0.05)；IL-8、IL-18、MMP9、ICAM和VCAM的表达与对照组差异无统计学意义(P>0.05)。8周、16周干预组NF-κB DNA结合活性平均灰度值均较对照组降低(P<0.05)。结论 普洱茶可能通过抑制NF-κB表达及活性而非通过IκB介导，促进巨噬细胞凋亡，同时降低体内炎症水平，进而发挥抗动脉粥样硬化作用。
ABSTRACT: Objective??? ?To explore the anti-atherosclerosis mechanism of pu-erh tea by reducing the expression and activity of NF-κB and promoting macrophage apoptosis. Methods?? ① ApoE-/- mice were fed with pu-erh tea extract for 8 and 16 weeks to observe the positive rate of CD68 and the area of lipid plaque. ② Apoptosis detection kit was used to detect the apoptosis of macrophages. ③ P65 and IkB-β expressions in aortic plaque and macrophages were detected by Real-time quantitative PCR and Western blot; the expressions of inflammatory factors in aortic plaque were detected. ④ Electrophoretic mobility change assay (EMSA) was used to analyze the binding activity of NF-κB DNA. Results?? ① The area fraction of lipid plaque in?ApoE-/- mice in the 16-week intervention group was significantly reduced (vs. control group, P<0.05). The area of lipid components in the 16-week intervention group was significantly reduced (vs. control group, P<0.05). ② The positive rate of CD68 in the plaque was significantly lower in the 8-week and 16-week intervention group than in the control group (vs. control group, P<0.05). The apoptosis rate of macrophages in aortic plaque (vs. control group, P<0.05). ③ The expressions of p65 gene and protein in macrophages of pu-erh tea extract intervention group 8 and 16 weeks decreased (vs. control group, P<0.05). The expressions of I-κBβ gene and protein in 16-week intervention group decreased (vs. control group, P<0.05). The relative expression levels of IL-6, IL-12 and TNF-α in aorta tissue of 16-week intervention group decreased compared with control group (vs. control group, all P<0.05). There was no significant difference in the expressions of IL-8, IL-18, MMP9, ICAM and VCAM between the two groups (vs. control group, all P>0.05). ④ The average gray value of NF-κB DNA binding activity in the 8- and 16-week intervention groups decreased respectively (vs. control group, P<0.05). Conclusion? ?Pu-erh tea