RESUMO
In this work we investigated the chemical constituents of water extract of the leaves of Cyclocarya paliurus. Two new megastigmane glycosides (3 and 8), three aliphatic alcohol glycosides (9-11), and two aromatic glycosides (12 and 13), along with fourteen known compounds were isolated, and their in vitro inhibitory activity against α-glucosidase was evaluated. Compounds 13 and 15-18 displayed inhibitory activity with IC50 values varying from 27.05 to 96.58 µM, and the structure-activity relationship among isolated compounds was discussed.
Assuntos
Glicosídeos , alfa-Glucosidases , Glicosídeos/química , alfa-Glucosidases/metabolismo , Extratos Vegetais/química , Água/análise , Estrutura Molecular , Folhas de Planta/químicaRESUMO
Cyclocarya paliurus, a Chinese herbal medicine and new food resource, contains a triterpenic-acid-rich extract that demonstrated ameliorative effect on diabetic nephropathy (DN). A more in-depth discovery of functional components led to the isolation of seven new triterpenoids including two pentacyclic triterpenes, 1α,2α,3ß,23-tetrahydroxyolean-12-en-28-oic acid and 2α,3ß,22α-tirhydroxyurs-12-en-28-oic acid 28-O-ß-D-glucopyranoside, and five tetracyclic triterpenoid glycosides (cypaliurusides N-R), together with twelve known compounds from the leaves of C. paliurus. Their structures were determined using a comprehensive analysis of chemical and spectroscopic data. Partial compounds were assessed for anti-fibrotic activities in high-glucose and TGF-ß1 induced HK-2 cells. Compound 16 remarkably decreased the level of fibronectin with an inhibition rate of 37.1%. Furthermore, 16 effectively alleviated the epithelial-mesenchymal transformation (EMT) process by upregulating E-cadherin expression and downregulating α-SMA expression, and it significantly decreased the level of the transcriptional inhibitors (Snail and Twist) of E-cadherin. The discovery of anti-fibrotic compounds from C. paliurus provides the potential utilization and functional candidates for the DN prevention.
