Benton H P, Tyler J A
Strangeways Research Laboratory, Worts Causeway, Cambridge, U.K.
Biochem Biophys Res Commun. 1988 Jul 15;154(1):421-8. doi: 10.1016/0006-291x(88)90703-6.
We have investigated the mechanism of inhibition of cartilage proteoglycan by interleukin 1. Proteoglycan synthesis was inhibited using lower doses of interleukin 1 than those required to cause cartilage resorption. There was no significant effect on DNA or total protein synthesis. Gel electrophoresis showed a direct inhibitory effect on core protein synthesis while pulse-chase experiments using radiolabelled sulphate showed no alteration in the rate of intracellular transport and secretion of completed proteoglycan. Chondrocytes incubated with cycloheximide showed a first-order decrease in rate of uptake of radiolabelled sulphate (t1/2 = 25 mins) but interleukin 1 induced inhibition showed a delay of at least 1 hr, consistent with a requirement to deplete intracellular pools of protein before effects on post-translational events could be observed. Foetal and neonatal cartilage responded to the cytokine in a similar way to adult cartilage.
我们已经研究了白细胞介素1抑制软骨蛋白聚糖的机制。与引起软骨吸收所需的剂量相比，使用较低剂量的白细胞介素1就能抑制蛋白聚糖的合成。对DNA或总蛋白合成没有显著影响。凝胶电泳显示对核心蛋白合成有直接抑制作用，而使用放射性标记硫酸盐的脉冲追踪实验表明，完整蛋白聚糖的细胞内运输和分泌速率没有改变。用环己酰亚胺孵育的软骨细胞显示放射性标记硫酸盐摄取速率呈一级下降（t1/2 = 25分钟），但白细胞介素1诱导的抑制作用至少延迟1小时，这与在观察到对翻译后事件的影响之前需要耗尽细胞内蛋白质池一致。胎儿和新生儿软骨对细胞因子的反应与成人软骨相似。
