Taxonomic group: plant / Streptophyta
(Phylum: Streptophyta)
Organ / tissue: leaf
NCBI PubMed ID: 10763585Publication DOI: 10.1055/s-2000-11135Journal NLM ID: 0066751Publisher: George Thieme
Correspondence: kadota
ms.toyama-mpu.ac.jp
Institutions: Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, Toyama, Japan
The leaves of Apocynum venetum L. are used as a tea material in north China and Japan. A water extract (500 mg/kg/day, one week administration) of the leaves of A. venetum showed protective effects against carbon tetrachloride (CCl4, 30 μl/mouse) or D-galactosamine (D-GalN, 700 mg/kg)/lipopolysaccharide (LPS, 20 μg/kg)-induced liver injury in mice. Tumor necrosis factor-α (TNF-α) secreted from LPS-stimulated macrophages is the most crucial mediator in the D-GalN/LPS-induced liver injury model. The extract had no significant inhibition on the increase of serum TNF-α (1169 ± 132 pg/ml vs. 1595 ± 314 pg/ml of control), but exhibited a complete inhibition at the concentration of 100 micrograms/ml on TNF-α (100 ng/ml)-induced cell death in D-GalN (0.5 mM)-sensitized mouse hepatocytes. Further activity-guided fractionation resulted in the isolation of fifteen flavonoids viz. (-)-epicatechin (1), (-)-epigallocatechin (2), isoquercetin (3), hyperin (4), (+)-catechin (5), (+)-gallocatechin (6), kaempferol-6'-O-acetate (7), isoquercetin-6'-O-acetate (8), catechin-[8,7-e]-4 α-(3,4-dihydroxpyhenyl)-dihydro-2(3H)-pyranone (9), apocynin B (10), apocynin A (11), cinchonain Ia (12), apocynin C (13), apocynin D (14) and quercetin (15). All the compounds showed inhibitory effects on TNF-α-induced cell death with different intensities. The flavonol glycosides 3, 4, 7 and 8 and the phenylpropanoid-substituted flavan-3-ols 11 and 12 showed potent inhibitory effects on TNF-α-induced cell death with IC50 values of 37.5, 14.5, 31.2, 55.1, 71.9 and 41.2 μM, respectively. In contrast, the clinically used 5 and its analogues 1, 2 and 6 showed apparent activity only at 80 microM. These flavonoids appeared to be the hepatoprotective principles of the leaves of A. venetum. The hepatoprotective effects exhibited by the extract and its constituents suggest a validation of the leaves as a tea material.
liver injury, hepatoprotective activity, Apocynum venetum
Structure type: monomer
Location inside paper: p. 130, Fig. 4, structure 3
Trivial name: isoquercitrin
Compound class: saponin glycoside, glycoside, flavonoid glycoside, flavonol glycoside, flavone glycoside
Contained glycoepitopes: IEDB_142488,IEDB_146664,IEDB_983931,SB_192
Methods: biological assays, extraction, optical rotation measurement, PTLC
Related record ID(s): 68652, 68653, 68654
NCBI Taxonomy refs (TaxIDs): 377125Reference(s) to other database(s): CCSD:
49965, CBank-STR:953
Show glycosyltransferases
There is only one chemically distinct structure: