钩藤提取物抑制血管紧张素Ⅱ诱导血管成纤维细胞增殖及胶原合成的研究

Uncaria extract inhibits VAF proliferation and collagen deposition induced by angiotensin Ⅱ

目的探讨钩藤碱和异钩藤碱对血管紧张素Ⅱ(AngⅡ)诱导的血管成纤维细胞(VAF)增殖及胶原沉积的抑制效应及相关机制。方法建立AngⅡ诱导VAF增殖模型,通过四甲基偶氮唑盐比色法、扫描电镜技术、流式细胞术、天狼猩红染色法和逆转录聚合酶链反应等观察钩藤碱和异钩藤碱对其增殖活性、细胞形态、细胞周期、细胞凋亡率、细胞c-myc蛋白表达、细胞培养液中羟脯氨酸含量、细胞间胶原蛋白含量、细胞ColⅠmRNA和ColⅢmRNA的影响。结果AngⅡ刺激VAF增殖,钩藤碱和异钩藤碱抑制AngⅡ诱导VAF增殖;在钩藤碱和异钩藤碱作用下VAF处于G0/G1期的细胞数增多、S期的细胞数减少、细胞凋亡率增加、细胞c-myc蛋白表达降低、细胞培养液中羟脯氨酸含量降低、细胞间胶原表达降低、细胞ColⅠmRNA和ColⅢmRNA转录也降低。结论钩藤碱和异钩藤碱对AngⅡ诱导VAF增殖和胶原沉积有抑制效应,部分机制与其阻滞VAF G0/G1期向S期转化、诱导细胞凋亡、下调细胞c-myc蛋白表达和细胞ColⅠmRNA和ColⅢmRNA转录有关。

Aim To study the inhibitory effect of rhynchophylline and isorhynchophylline alkaloids as well as Uncaria species total alkaloids on the proliferation of vascular adventitial fibroblasts（VAFs） and the deposition of collagen（Col）,induced by angiotensin Ⅱ（Ang Ⅱ）,as well as the mechanisms underlying this process.Methods A VAF proliferation model induced by Ang Ⅱ was firstly established.Then VAF proliferative activity,cell morphology,cell cycle,rate of apoptosis,c-Myc protein expression,hydroxyproline content in the culture medium,as well as Col Ⅰ and Col Ⅲ mRNA expression and protein expression after VAFs were treated with extract from Uncaria were examined by using methods including MTT,scanning electron microscopy,flow cytometry,Sirius Red staining and reverse transcriptase-polymerase chain reaction.Results Ang Ⅱ significantly increased the proliferation of VAFs,whereas rhynchophylline,isorhynchophylline,and Uncaria total alkaloids inhibited VAF proliferation.Treatment of VAFs with Uncaria extract led to an increased percentage of VAFs in the G0/G1 phase of the cell cycle and a decreased percentage of cells in the S phase of the cell cycle,increased apoptotic rate,reduced c-Myc protein expression,decreased hydroxyproline content,and reduced extracellular collagen mRNA expression.Conclusions Rhynchophylline,isorhynchophylline,and Uncaria total alkaloids exhibit a significant inhibitory effect on VAF proliferation and collagen deposition induced by Ang Ⅱ.Uncaria is a plant with potential benefits against the vascular remodeling associated with hypertension.