Suzuki Y, Koyama J, Moro O, Horii I, Kikuchi K, Tanida M, Tagami H
Shiseido Research Center, Yokohama, Japan.
Br J Dermatol. 1996 Mar;134(3):460-4.
We investigated the role of stratum corneum (SC) trypsin-like and chymotrypsin-like serine proteases in the degradation of desmoglein-1 (DSG-1) in the SC sheet. DSG-1, whose presence in the SC sheet was confirmed by Western blot analysis, was degraded completely during incubation of the SC sheet in Tris buffer. The degradation of DSG-1 was inhibited by the addition of protease inhibitors, such as aprotinin or a mixture of leupeptin and chymostatin. Either leupeptin or chymostatin alone did not inhibit its degradation. These results indicated that both trypsin-like and chymotrypsin-like serine proteases are involved in the degradation of DSG-1. We further examined the activities of the two proteases in the SC obtained from patients with ichthyosis vulgaris, in whom SC desquamation is abnormal. The enzymatic activities measured using synthetic substrates were significantly decreased in these ichthyotic SC samples. This result supports the idea that these proteases play an important role in normal SC desquamation.
我们研究了角质层（SC）中类胰蛋白酶和类糜蛋白酶样丝氨酸蛋白酶在SC薄片中桥粒芯糖蛋白-1（DSG-1）降解过程中的作用。通过蛋白质印迹分析证实了DSG-1在SC薄片中的存在，在将SC薄片置于Tris缓冲液中孵育期间，DSG-1被完全降解。添加蛋白酶抑制剂，如抑肽酶或亮抑酶肽与糜蛋白酶抑制剂的混合物，可抑制DSG-1的降解。单独使用亮抑酶肽或糜蛋白酶抑制剂均不能抑制其降解。这些结果表明，类胰蛋白酶和类糜蛋白酶样丝氨酸蛋白酶均参与了DSG-1的降解。我们进一步检测了寻常型鱼鳞病患者的SC中这两种蛋白酶的活性，这些患者的SC脱屑异常。使用合成底物测定的酶活性在这些鱼鳞病的SC样本中显著降低。这一结果支持了这些蛋白酶在正常SC脱屑中起重要作用的观点。
