Bingley J A, Hayward I P, Campbell J H, Campbell G R
Centre for Research in Vascular Biology and CRC for Cardiac Technology, Department of Anatomical Sciences, University of Queensland, Australia.
J Vasc Surg. 1998 Aug;28(2):308-18. doi: 10.1016/s0741-5214(98)70167-3.
The aim of this study was to determine whether heparan sulfate proteoglycans (HSPGs) from the normal arterial wall inhibit neointimal formation after injury in vivo and smooth muscle cell (SMC) phenotype change and proliferation in vitro.
Arterial HSPGs were extracted from rabbit aortae and separated by anion-exchange chromatography. The effect of HSPGs, applied in a periadventitial gel, on neointimal formation was assessed 14 days after balloon catheter injury of rabbit carotid arteries. Their effect on SMC phenotype and proliferation was measured by point-counting morphometry of the cytoplasmic volume fraction of myofilaments (Vvmyo) and 3H-thymidine incorporation in SMCs in culture.
Arterial HSPGs (680 microg) reduced neointimal formation by 35% at 14 days after injury (P=.029), whereas 2000 microg of the low-molecular-weight heparin Enoxaparin was ineffective. HSPGs at 34 microg/mL maintained subconfluent primary cultured SMCs with the same high Vvmyo (52.1%+/-13.8%) after 5 days in culture as did cells freshly isolated from the arterial wall (52.1%+/-15.1%). In contrast, 100 microg/mL Enoxaparin was ineffective in preventing phenotypic change over this time period (Vvmyo 38.9%+/-14.6%, controls 35.9%+/-12.8%). HSPGs also inhibited 3H-thymidine incorporation into primary cultured SMCs with an ID50 value of 0.4 microg/mL compared with a value of 14 microg/mL for Enoxaparin (P< .01).
When used periadventitially in the rabbit arterial injury model, natural arterial HSPGs are effective inhibitors of neointimal formation. In vitro, the HSPGs maintain SMCs in a quiescent state by inhibiting phenotypic change and DNA synthesis. This study suggests that HSPGs may be a natural agent for the treatment of clinical restenosis.
本研究旨在确定正常动脉壁中的硫酸乙酰肝素蛋白聚糖（HSPGs）是否能在体内抑制损伤后的内膜增生，以及在体外抑制平滑肌细胞（SMC）表型改变和增殖。
从兔主动脉中提取动脉HSPGs，并通过阴离子交换色谱法进行分离。在兔颈动脉球囊导管损伤14天后，评估应用于外膜凝胶中的HSPGs对内膜增生的影响。通过对培养的SMC中肌丝细胞质体积分数（Vvmyo）进行点计数形态测量以及测量3H-胸腺嘧啶核苷掺入量，来测定它们对SMC表型和增殖的影响。
动脉HSPGs（680微克）在损伤后14天时使内膜增生减少35%（P = 0.029），而2000微克的低分子量肝素依诺肝素则无效。培养5天后，34微克/毫升的HSPGs使亚汇合的原代培养SMC维持与刚从动脉壁分离的细胞相同的高Vvmyo（52.1%±13.8%）。相比之下，100微克/毫升的依诺肝素在此时间段内无法有效防止表型改变（Vvmyo 38.9%±14.6%，对照组35.9%±12.8%）。HSPGs还抑制3H-胸腺嘧啶核苷掺入原代培养的SMC，其半数抑制浓度（ID50）值为0.4微克/毫升，而依诺肝素的值为14微克/毫升（P < 0.01）。
在兔动脉损伤模型中外膜应用时，天然动脉HSPGs是内膜增生的有效抑制剂。在体外，HSPGs通过抑制表型改变和DNA合成使SMC维持在静止状态。本研究表明，HSPGs可能是治疗临床再狭窄的天然药物。
