Zymosan enhances leukotriene D4 metabolism by porcine alveolar macrophages.
Zymosan enhances leukotriene D4 metabolism by porcine alveolar macrophages.
复制标题
酵母聚糖可增强猪肺泡巨噬细胞对白三烯 D4 的代谢。
作者：
N. Paterson;D. McIver;S. Schurch
猪肺泡巨噬细胞（AM）将白三烯D4 （LTD4）代谢为白三烯E4 （LTE4）。在本研究中，研究了液相AM刺激（A23187）和吞噬刺激（调理酵素）增强LTD4代谢的能力。两种刺激都增加了超氧化物（O-2）阴离子的释放。然而，酶生酶能引起表面自由能的一致降低，而A23187的影响是可变的。同样，zymosan诱导溶酶体酶n -乙酰- β - d -氨基葡萄糖苷酶和芳基硫酸盐酶的平均净释放量分别为14.9%和12.0%，而A23187诱导的释放量较小（平均净释放量分别为1.42%和1.31%），且具有边际统计学意义。Zymosan，而不是A23187，导致LTD4失活的显著增强（P < 0.005）：对照AM在60分钟时从93 +/- 7pm /10(7)个细胞（占添加LTD4的69 +/- 5%），到Zymosan处理AM在60分钟时的117 +/- 3pm /10(7)个细胞（占添加LTD4的88 +/- 2%）。Zymosan还诱导LTD4失活能力（128 +/- 21 pM LTD4/10(7) AM/60 min）释放到上清液中。酶解AM及其上清液对LTD4转化为LTE4进行了色谱分析。此外，AM及其上清液的LTD4失活被10 mM l -半胱氨酸抑制。这些数据表明，zymosan释放了一种可能源于溶酶体的二肽酶，催化LTD4转化为LTE4。
Porcine alveolar macrophages (AM) metabolize leukotriene D4 (LTD4) to leukotriene E4 (LTE4). In the present study, the ability of a fluid-phase AM stimulus (A23187) and a phagocytic stimulus (opsonized zymosan) to augment LTD4 metabolism was examined. Both stimuli increased the release of superoxide (O-2) anions. However, whereas zymosan caused a consistent reduction in surface free energy, the effect of A23187 was variable. Similarly, zymosan induced release of the lysosomal enzymes N-acetyl-beta-D-glucosaminidase and arylsulphatase (mean net release, 14.9% and 12.0%, respectively), whereas release induced by A23187 was smaller (mean net release 1.42% and 1.31%, respectively) and of marginal statistical significance. Zymosan, but not A23187, caused a significant (P less than 0.005) augmentation of LTD4 inactivation: from 93 +/- 7 pM/10(7) cells (69 +/- 5% of added LTD4) at 60 min by control AM, to 117 +/- 3 pM/10(7) cells (88 +/- 2% of added LTD4) at 60 min by zymosan-treated AM. Zymosan also induced the release of LTD4 inactivating capacity (128 +/- 21 pM LTD4/10(7) AM/60 min) into the supernatant. Conversion of LTD4 to LTE4 by zymosan-treated AM and their supernatants was confirmed chromatographically. In addition, LTD4 inactivation by AM and their supernatants was inhibited by 10 mM L-cysteine. These data suggest that zymosan released a dipeptidase, possibly of lysosomal origin, which catalysed the conversion of LTD4 to LTE4.