ABSTRACT
Eleven oleanane triterpenoids (1-11) including two new ones (1 and 2) were isolated from the roots and stems of Caulophyllum robustum. Their structures were established by extensive spectroscopic analysis, comparison with literature, and NMR calculations. Compounds 1 and 2 represent the first examples of 23-hydroxy-28-nor-oleanane and 21-hydroxy-olean-3-one triterpenoids, respectively. All isolates were evaluated for their PTP1B and α-glucosidase inhibitory activities in vitro. Among them, the triterpene aglycones 1-5 showed almost equivalent PTP1B inhibitory activities to oleanolic acid and ursolic acid, while 1, 2, and the triterpene saponins 6-11 showed significant α-glucosidase inhibitory activities. Furthermore, compounds 1 and 3 were proved to regulate the expression of proteins implicated the PTP1B/IRS-1/pIRS-1 signalling pathway to improve insulin resistance.
ABSTRACT
Caulophyllum robustum Maxim is widely distributed in China and used as a traditional herbal medicine to induce childbirth, ease the pain of labor, rectify delayed or irregular menstruation, alleviate heavy bleeding and pain during menstruation, and treat external injuries and irregular menses. According to our detailed chemical investigation, three new triterpene derivatives (1â»3), together with seven known compounds, were isolated from the root and rhizome of C. robustum Maxim. Their structures were elucidated by 1D- and 2D-NMR spectroscopic analysis and physio-chemical methods. They were identified as (1) 23-hydroxy-3,19-dioxo-olean-12-en-28-oic-acid; (2) 23-hydroxy-3,11-dioxo-olean-12-en-28-oic acid; and (3) 16α,23-dihydroxy-3-oxo-olean-12-en-28-oic acid. Compounds (1â»10) inhibited the LPS-activated NO production in RAW264.7 cells. Furthermore, the anti-inflammatory characteristics of these compounds were confirmed on the basis of decreases in iNOS and NF-κB protein expression in RAW264.7 cells.
Subject(s)
Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Caulophyllum/chemistry , Triterpenes/chemistry , Triterpenes/pharmacology , Animals , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Magnetic Resonance Spectroscopy , Mice , Molecular Structure , Nitric Oxide/metabolism , RAW 264.7 CellsABSTRACT
Two new phenanthrene glucosides, named 2'-hydroxy-4,4',7'-trimethoxy-1, l'-biphenanthrene-2,7-di-O-ß-D-glucoside (1) and 1-(4-hydroxybenzyl)-4-methoxy-2,7-dihydroxy-phenanthrene-8-O-ß-D-glucoside (2), together with three known compounds were isolated from the tubers of Cremastra appendiculata (D.Don) Makino. Their structures were elucidated on the basis of spectral data. Compounds 1-4 showed moderate cytotoxic activity and compound 5 showed weak cytotoxic activity against the two cell lines tested. This is the first reported occurrence of an unusual biphenanthrene glucoside in this plant.
