标题：不同浓度茶多酚对脂多糖诱导的内皮细胞中NF-κB p65表达的影响

      作者：李百齐 1，许伟 1，李萍 2，高丽 3，宋琦 2，张庭婷 1    1.遵义医科大学口腔医学，贵州 遵义 563099；2.遵义医科大学附属口腔医院病理科，贵州 遵义 563099；3.遵义医科大学附属口腔医院牙周科，贵州 遵义 563099

      卷次： 2021年32卷15期

      【摘要】 目的 探讨不同浓度茶多酚(TP)对牙龈卟啉单胞菌脂多糖(Pg-LPS)诱导的人脐静脉内皮细胞(HUVECs)中核因子-κB (NF-κB) p65表达影响。方法 选取不同浓度的TP和Pg-LPS作用于HUVECs，用CCK-8细胞活性检测法对TP和Pg-LPS药物浓度进行筛选，选取Pg-LPS诱导TP预刺激后最适浓度的HUVECs建立炎症反应实验模型，将实验分为Control组、Pg-LPS组、LPS+TP1组(5 mg/L)和LPS+TP2组(40 mg/L)，用Western blot法检测细胞核及胞浆内NF-κB p65蛋白表达。结果 在不同浓度TP作用下(5 mg/L、10 mg/L、20 mg/L、40 mg/L)，12 h HUVECs增殖率较24 h和48 h高，差异有统计学意义(P<0.05)，其中作用浓度在5~40 mg/L时促进HUVECs增殖，达到80 mg/L后出现抑制作用；与Control组比较，在不同时间、浓度条件下(4 h、8 h、24 h；0.1 μg/mL、1 μg/mL、10 μg/mL)，Pg-LPS均会对细胞增殖产生抑制作用，且抑制率与作用时间和浓度相关(P<0.05)，其中在相同作用时间下，浓度为10 μg/mL的Pg-LPS的细胞抑制率最高，在相同浓度下，Pg-LPS作用24 h后细胞抑制率最高，在Pg-LPS的作用下，细胞核内的p65表达增加而胞浆内的p65表达降低；选取一定浓度的TP预处理HUVECs后，细胞核内NF-κB p65蛋白表达降低，浆内NF-κB p65蛋白表达增加。结论 TP对HUVECs的增殖与抑制作用与浓度及时间有密切的关系，具有低浓度促进、高浓度抑制与短时促进、长时抑制的作用；TP抑制Pg-LPS诱导的HUVECs中NF-κB p65由胞浆转位至细胞核，即抑制NF-κB p65活化，对HUVECs具有一定的保护作用。
      【关键词】 茶多酚；脂多糖；牙龈卟啉单胞菌；核因子-κB；牙周炎；心血管疾病
      【中图分类号】R781.4 【文献标识码】 A 【文章编号】 1003—6350（2021）15—1905—04

Effect of tea polyphenols on the expression levels of NF-κB p65 in HUVECs induced by lipopolysaccharide.
LIBai-qi 1, XU Wei 1, LI Ping 2, GAO Li 3, SONG Qi 2, ZHANG Ting-ting 1. 1. Zunyi Medical University, Zunyi 563099, Guizhou,CHINA; 2. Department of Pathology, Hospital of Stomatology, Zunyi Medical University, Zunyi 563099, Guizhou, CHINA;3. Department of Periodontics, Hospital of Stomatology, Zunyi Medical University, Zunyi 563099, Guizhou, CHINA
【Abstract】 Objective To explore the effect of tea polyphenols (TP) on porphyromonas gingivalis lipopolysac-charide (Pg-LPS)-induced nuclear factor kppa B (NF-κB) p65 expression in human umbilical vein endothelial cells (HU-VECs). Methods Different concentrations of TP and Pg-LPS were selected to treat HUVECs. The concentrations of TPand Pg-LPS were screened by CCK-8 cell activity assay. The optimal concentration of HUVECs with Pg-LPS-induced TPprestimulation was selected to establish an experimental model of inflammatory response. The experiment was divided in-to four groups: control group, PG-LPS group, LPS+TP1 (5 mg/L), LPS+TP2 (40 mg/L). The expressed of intracellularNF-κB p65 protein was detected by western blot. Results Under different TP concentration (5 mg/L, 10 mg/L, 20 mg/L,40 mg/L), the proliferation rate of 12 h HUVECs was significantly higher than that of 24 h and 48 h (P<0.05), and the pro-liferation of HUVECs was promoted at the concentration of 5-40 mg/L and inhibited at the concentration of 80 mg/L. Indifferent time and concentrations (4 h, 8 h, 24 h; 0.1 μg/mL, 1μg/mL, 10 μg/mL), Pg-LPS could inhibit cell proliferation,and the inhibition rate was correlated with time and concentration (P<0.05); at the same time, 10 μg/mL Pg-LPS had thehighest inhibition rate on cells, and at the same concentration of Pg-LPS, the inhibition rate was the highest at 24 h. What'smore, Pg-LPS increased the expression of p65 in nucleus and decreased the expression of p65 in cytoplasm. TP can de-crease the expression of p65 in nucleus and increase the expression of p65 in cytoplasm. Conclusion TP has a close rela-tionship with concentration and time, and has the functions of low concentration promotion, high concentration inhibition,short-term promotion and long-term inhibition. TP inhibits the transformation of NF-κB p65 from cytoplasm to nucleus,the same as inhibition of activation of NF-κB p65, which has a certain protective effect on HUVECs.
      【Key words】 Tea polyphenols; Lipopolysaccharide; Porphyromonas gingivalis; NF-κB; Periodontitis; Cardiovas-cular diseases