Sinn W, Sudhakaran P R, Von Figura K
Biochem J. 1981 Oct 15;200(1):51-7. doi: 10.1042/bj2000051.
The secretion of heparan sulphate by cultured rat hepatocytes was increased in the presence of (+)-catechin. The increase was due to a new species of heparan sulphate that lacked the carbohydrate-protein linkage between xylose and serine in normal heparan sulphate proteoglycan. The mean molecular weight of this heparan sulphate varied between 6300 and 9500, was not affected by treatment with alkali or Pronase and was 2-3-fold lower than that of chains released from heparan sulphate proteoglycan. After digestion with Pronase, only a minor fraction of chains contained serine, and after treatment with alkali and NaB3H4 reduction less than 5% of the chains exposed [3H]xylitol at the reducing terminals. These results suggested that (+)-catechin or metabolites of it acted as acceptors of heparan sulphate synthesis. In cultures treated wih cycloheximide, synthesis of heparan sulphate decreased to less than 5%. (+)-Catechin could restore the heparan sulphate synthesis to almost normal values. The (+)-catechin-induced heparan sulphate was secreted. Only a small fraction was incorporated into the plasma membrane or other cellular compartments. This may indicate that the protein core is essential for association of heparan sulphate with cellular compartments.
在（+）-儿茶素存在的情况下，培养的大鼠肝细胞硫酸乙酰肝素的分泌增加。这种增加是由于一种新的硫酸乙酰肝素，它在正常硫酸乙酰肝素蛋白聚糖中缺乏木糖和丝氨酸之间的碳水化合物-蛋白质连接。这种硫酸乙酰肝素的平均分子量在6300至9500之间，不受碱或链霉蛋白酶处理的影响，并且比从硫酸乙酰肝素蛋白聚糖释放的链低2至3倍。用链霉蛋白酶消化后，只有一小部分链含有丝氨酸，用碱处理并经NaB3H4还原后，不到5%的链在还原末端暴露[3H]木糖醇。这些结果表明（+）-儿茶素或其代谢产物作为硫酸乙酰肝素合成的受体。在用环己酰亚胺处理的培养物中，硫酸乙酰肝素的合成降至不到5%。（+）-儿茶素可以将硫酸乙酰肝素的合成恢复到几乎正常的值。（+）-儿茶素诱导的硫酸乙酰肝素被分泌。只有一小部分被整合到质膜或其他细胞区室中。这可能表明蛋白质核心对于硫酸乙酰肝素与细胞区室的结合至关重要。
