Akao T
Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Japan.
Biol Pharm Bull. 1998 Oct;21(10):1036-44. doi: 10.1248/bpb.21.1036.
Glycyrrhizin (GL) was hydrolyzed to glycyrrhetic acid (GA), glycyrrhetic acid mono-beta-D-glucuronide (GAMG) or both by glucuronidases in various organs of rat. GL beta-D-glucuronidase I, hydrolyzing GL to GA; GAMG beta-D-glucuronidase, hydrolyzing GAMG to GA; and 3alpha-hydroxyglycyrrhetinate (3alpha-hydroxyGA) dehydrogenase, oxidizing 3alpha-hydroxyGA to 3-oxo-GA were found in the organs of this animal. GL beta-D-glucuronidase II was distributed in the lysosomal fraction of all organs except brain; 3alpha-hydroxyGA dehydrogenase was distributed in the microsomal fraction of the liver; but other enzymes were distributed in the nuclear, lysosomal, microsomal and soluble fractions of a variety of organs. GL beta-D-glucuronidase I, GL beta-D-glucuronidase II and GAMG beta-D-glucuronidase activities in a mixture of lysosomes and microsomes of rat liver exhibited different patterns on hydroxyapatite column chromatography. These results showed the metabolic pathways of GL to be of two types: a beta-D-glucuronidase hydrolyzing GL to GA, and the other consisting of two different beta-D-glucuronidases hydrolyzing GL to GAMG and GAMG to GA.
在大鼠的各个器官中，甘草酸（GL）被葡萄糖醛酸酶水解为甘草次酸（GA）、甘草次酸单-β-D-葡萄糖醛酸苷（GAMG）或两者。在该动物的器官中发现了GL β-D-葡萄糖醛酸酶I（将GL水解为GA）、GAMG β-D-葡萄糖醛酸酶（将GAMG水解为GA）以及3α-羟基甘草次酸（3α-羟基GA）脱氢酶（将3α-羟基GA氧化为3-氧代-GA）。GL β-D-葡萄糖醛酸酶II分布于除脑以外所有器官的溶酶体部分；3α-羟基GA脱氢酶分布于肝脏的微粒体部分；但其他酶分布于多种器官的细胞核、溶酶体、微粒体和可溶性部分。大鼠肝脏溶酶体和微粒体混合物中的GL β-D-葡萄糖醛酸酶I、GL β-D-葡萄糖醛酸酶II和GAMG β-D-葡萄糖醛酸酶活性在羟基磷灰石柱色谱上呈现出不同的模式。这些结果表明GL的代谢途径有两种类型：一种是β-D-葡萄糖醛酸酶将GL水解为GA，另一种是由两种不同的β-D-葡萄糖醛酸酶将GL水解为GAMG以及将GAMG水解为GA。
