Fält H, Hernell O, Bläckberg L
Department of Medical Biosciences, Umeå University, Sweden.
Arch Biochem Biophys. 2001 Feb 15;386(2):188-94. doi: 10.1006/abbi.2000.2071.
Bile salt stimulated lipase (BSSL), a lipolytic enzyme secreted with pancreatic juice and with human milk, is in concert with colipase-dependent pancreatic lipase, important for the intestinal digestion of dietary lipids. BSSL may also facilitate uptake of free cholesterol from the intestinal lumen, while colipase-dependent lipase has a similar role for fatty acids. According to this theory, the two lipases bind to the intestinal mucosa via a common heparin-involving receptor. In the present study, binding of the two lipases to heparin was explored in vitro using purified human lipases and heparin molecules varying in both chain length and charge density. Native, but not denatured, BSSL bound avidly to heparin and several of the heparin variants. In contrast, at physiologic salt concentration, colipase-dependent lipase did not bind to heparin. Thus, our data do not support the view that the two lipases share a common intestinal heparin-like receptor. Hence, it seems unlikely that such binding could be of physiologic relevance for colipase-dependent lipase, although for BSSL the data are supportive.
胆汁盐刺激脂肪酶（BSSL）是一种与胰液和人乳一同分泌的脂肪分解酶，它与依赖辅脂酶的胰脂肪酶协同作用，对膳食脂质的肠道消化很重要。BSSL还可能促进从肠腔摄取游离胆固醇，而依赖辅脂酶的脂肪酶对脂肪酸具有类似作用。根据这一理论，这两种脂肪酶通过一个共同的涉及肝素的受体与肠黏膜结合。在本研究中，使用纯化的人脂肪酶和链长度及电荷密度不同的肝素分子，在体外探索了这两种脂肪酶与肝素的结合。天然的而非变性的BSSL能与肝素及几种肝素变体紧密结合。相比之下，在生理盐浓度下，依赖辅脂酶的脂肪酶不与肝素结合。因此，我们的数据不支持这两种脂肪酶共享一个共同的肠道类肝素受体这一观点。所以，尽管数据支持BSSL，但这种结合对依赖辅脂酶的脂肪酶而言似乎不太可能具有生理相关性。
