Kawabata K, Moore A R, Willoughby D A
Department of Experimental Pathology, William Harvey Research Institute, St Bartholomew's Hospital Medical College, London, United Kingdom.
Ann Rheum Dis. 1996 Apr;55(4):248-52. doi: 10.1136/ard.55.4.248.
To investigate the effects of protease inhibitors on the ability of free and cartilage bound neutrophil elastase to degrade cartilage proteoglycan in vitro.
Cryostat sections of human articular cartilage were used as substrate, and proteoglycan loss induced by free or cartilage bound elastase was quantified by alcian blue staining, followed by scanning and integrating microdensitometry.
High molecular mass protease inhibitors (alpha 1 protease inhibitor, alpha 2 macroglobulin, and soya bean trypsin inhibitor) and synovial fluid from patients with rheumatoid arthritis were effective in blocking proteoglycan loss from sections treated with free elastase, but their activity towards cartilage bound elastase was much reduced. In contrast, low molecular mass elastase inhibitors (N-methoxysuccinyl-Ala-Ala-Pro-Val chloromethyl ketone and ONO-5046 (N-[2-[4-(2,2-dimethylpropionyloxy) phenylsulphonylamino]benzoyl] amino-acetic acid) were effective against free and cartilage bound elastase.
The binding of elastase to cartilage appears to be a mechanism whereby the enzyme can remain active in the presence of high molecular mass protease inhibitors.
研究蛋白酶抑制剂对游离及与软骨结合的中性粒细胞弹性蛋白酶在体外降解软骨蛋白聚糖能力的影响。
用人关节软骨的冷冻切片作为底物，通过阿尔新蓝染色，随后进行扫描和积分光密度测定，对游离或与软骨结合的弹性蛋白酶诱导的蛋白聚糖损失进行定量。
高分子量蛋白酶抑制剂（α1蛋白酶抑制剂、α2巨球蛋白和大豆胰蛋白酶抑制剂）以及类风湿性关节炎患者的滑液可有效阻止游离弹性蛋白酶处理切片中的蛋白聚糖损失，但其对与软骨结合的弹性蛋白酶的活性则大大降低。相比之下，低分子量弹性蛋白酶抑制剂（N-甲氧基琥珀酰-Ala-Ala-Pro-Val氯甲基酮和ONO-5046（N-[2-[4-(2,2-二甲基丙酰氧基)苯基磺酰氨基]苯甲酰]氨基乙酸）对游离及与软骨结合的弹性蛋白酶均有效。
弹性蛋白酶与软骨的结合似乎是一种机制，通过该机制酶在高分子量蛋白酶抑制剂存在时仍能保持活性。
