摘要
目的研究游离脂肪酸(FFA)水平升高导致的内皮一氧化氮合酶(eNOS)活性降低是否与蛋白激酶C(PKC)通路激活有关。方法传代培养的人脐静脉内皮细胞分为4组:对照组,油酸组(10、50、100、150、200μmol/L),PKC抑制剂(GFX)组,油酸+GFX组。分别检测各组eNOS活性,检测对照组和油酸组PKC的表达和活性,以及各组eNOS磷酸化(p-eNOS)的表达。结果与对照组相比,油酸组eNOS活性呈剂量依赖性降低,p-eNOS(1177)的表达降低(0.0854±0.017 vs.0.0134±0.023,P<0.05);PKC的表达出现转位,由胞浆转向胞膜,胞浆表达活性降低,胞膜表达活性增高,总活性增加。加入GFX后对正常内皮细胞eNOS活性无明显影响,但能部分改善油酸所致的内皮细胞eNOS活性的降低。结论油酸可损害内皮细胞eNOS的表达及磷酸化,其机理与PKC通路的激活有关。
Objective To observe whether the impairment of endothelial nitric oxide synthase（eNOS） activity by elevated level of free fatty acid（FFA） is associated with activation of protein kinase C（PKC）.Methods The cultured human umbilical vein endothelial cells were used for four groups： control group,oleic acid（OA） group（10,50,100,150,200 μmol/L）,GFX group and OA＋GFX group.The activity of eNOS in each group was examined,and the activity and expression of PKC were determined in both control and OA groups.The method of immunocytochemistry was performed to detect the expression of p-eNOS（1177） in control,OA（100 μmol/L）,GFX and OA＋GFX groups respectively.Results Compared with control group,the eNOS activity of endothelial cells in OA group was significantly reduced in a dose-dependent manner,and the expression of p-eNOS（1177） were also impaired（0.0854±0.017 vs.0.0134±0.023,P〈0.05）.PKC transposition from endochylema to cytomembrane was observed by confocal microscopy.The PKC activity was degraded in endochylema,while enhanced in cell membrane inversely,and the gross activity of PKC increased after all.When GFX,an inhibition of PKC,was added to endothelial cells at the present of OA or not,the impaired eNOS activity were partly improved.Conclusion Elevated level of FFA（here is oleic acid） leading to endothelial dysfunction results from a loss of eNOS activity and its serine phosphorylation,and it may be related to activation of PKC.
出处
《四川大学学报（医学版）》
CAS
CSCD
北大核心
2010年第2期208-211,225,共5页
Journal of Sichuan University(Medical Sciences)
基金
国家自然科学基金(批准号30570874
30370679)资助
关键词
游离脂肪酸
内皮细胞
内皮一氧化氮合酶
蛋白激酶C
Free fatty acids Endothelial cells Endothelial nitricoxide synthase Protein kinase C
