Abnormal cathepsin B activity in Batten disease.
Abnormal cathepsin B activity in Batten disease.
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Batten 病中组织蛋白酶 B 活性异常。
DOI：
10.1002/ajmg.1320310624
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Glaser,PT
中科院分区：
文献类型：
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作者：
Dawson,G;Glaser,PT
从患有各种形式的神经元蜡样质-脂褐质沉积症（NCL;巴滕病）的患者培养的成纤维细胞显示，在存在胎牛血清的情况下，随着传代次数和培养时间的增加，组织蛋白酶B活性急剧降低。组织蛋白酶H的活性和广泛的溶酶体水解酶是不受这些条件。在NaDodSO 4 -12.5%聚丙烯酰胺凝胶电泳（[125]Tyr-Ala-Lys-Arg-CH 2Cl）后，通过比色法（Nα-苯甲酰基-DL-Arg-β-萘胺; BANA）、荧光法（Z-Arg-Arg-甲基香豆素）或放射自显影法测定组织蛋白酶B活性，发现其定位于溶酶体。在Percoll梯度上分离破坏的成纤维细胞显示在一些NCL患者中存在异常浮力溶酶体的证据，并且这些溶酶体倾向于组织蛋白酶B低，但富含其他溶酶体水解酶。我们的数据不支持组织蛋白酶B的原发性缺陷作为NCL的基本缺陷。然而，各种研究暗示NCL中蛋白酶缺陷的可能解释是组织蛋白酶B对过氧化物和醛的失活高度敏感。因此，过氧化氢（0.3 mM）或4-羟基壬烯醛（1 nM）可灭活组织蛋白酶B，而不会抑制组织蛋白酶H或溶酶体水解酶（如α-L-岩藻糖苷酶）。由于过氧化物和4-羟基壬烯醛已被证明在NCL组织中蓄积（尽管过氧化物酶活性明显正常），我们检测了从磷脂中去除过氧化脂质缺陷作为NCL主要缺陷的可能性。伤害性肽缓激肽（BK）通常启动一个级联反应，涉及受体介导的磷脂酶C激活和花生四烯酸和前列腺素类从培养的皮肤成纤维细胞释放。BK释放[3 H]花生四烯酸在NCL成纤维细胞中是缺乏的，这表明NCL中的主要缺陷可能涉及特定磷脂酶A2活性的缺乏。
Fibroblasts cultured from patients with various forms of neuronal ceroid‐lipofuscinosis (NCL; Batten disease) showed variably decreasing cathepsin B activity with increasing passage number and months in culture in the presence of fetal calf serum. Cathepsin H activity and that of a wide range of lysosomal hydrolases was unaffected by these conditions. Cathepsin B activity was assayed either colorimetrically (Nα‐benzoyl‐DL‐Arg‐β‐naphthylamide; BANA), fluorimetrically (Z‐Arg‐Arg‐methylcoumarin), or autoradiographically, following NaDodSO4–12.5% polyacrylamide gel electrophoresis ([125]Tyr‐Ala‐Lys‐Arg‐CH2Cl) and was found to be lysosomal in localization. Fractionation of disrupted fibroblasts on a Percoll gradient showed evidence of abnormally buoyant lysosomes in some NCL patients, and these tended to be low in cathepsin B but rich in other lysosomal hydrolases. Our data do not support a primary defect in cathepsin B as the basic defect in NCL. However, a possible explanation for various studies implicating a protease defect in NCL is that cathepsin B was highly sensitive to inactivation by peroxides and aldehydes. Thus hydrogen peroxide (0.3 mM) or 4‐hydroxynonenal (1 nM) inactivated cathepsin B without inhibiting cathepsin H or lysosomal hydrolases such as α‐L‐fucosidase. Since peroxides and 4‐hydroxynonenal have been shown to accumulate in NCL tissue (despite apparently normal peroxidase activity), we tested the possibility of a defect in the removal of peroxidized lipids from phospholipids as the primary defect in NCL. The nociceptive peptide bradykinin (BK) normally initiates a cascade involving receptor‐mediated phospholipase C activation and release of arachidonate and prostanoids from cultured skin fibroblasts. Release of [3H]arachidonate by BK was deficient in NCL fibroblasts, suggesting that the primary defect in NCL could involve the deficiency of a specific phospholipase A2activity.