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Liver X receptor and peroxisome proliferator-activated receptor agonist from Cornus alternifolia.

ABSTRACT: Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptors superfamily and are transcription factors activated by specific ligands. Liver X receptors (LXR) belong to the nuclear hormone receptors and have been shown to play an important role in cholesterol homeostasis. From the previous screening of several medicinal plants for potential partial PPAR? agonists, the extracts of Cornus alternifolia were found to exhibit promising bioactivity. In this paper, we report the isolation and structural elucidation of four new compounds and their potential as ligands for PPAR.The new compounds were extracted from the leaves of C. alternifolia and fractionated by high-performance liquid chromatography. Their structures were elucidated on the basis of spectroscopic evidence and analysis of their hydrolysis products.Three new iridoid glycosides including an iridolactone, alternosides A-C (1-3), a new megastigmane glycoside, cornalternoside (4) and 10 known compounds, were obtained from the leaves of C. alternifolia. Kaempferol-3-O-?-glucopyranoside (5) exhibited potent agonistic activities for PPAR?, PPAR? and LXR with EC50 values of 0.62, 3.0 and 1.8 ?M, respectively.We isolated four new and ten known compounds from C. alternifolia, and one known compound showed agonistic activities for PPAR?, PPAR? and LXR.Compound 1 is the first example of a naturally occurring iridoid glycoside containing a ?-glucopyranoside moiety at C-6.

SUBMITTER: He YQ

PROVIDER: S-EPMC3482494 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Liver X receptor and peroxisome proliferator-activated receptor agonist from Cornus alternifolia.

He Yang-Qing YQ Ma Guo-Yi GY Peng Jiang-nan JN Ma Zhan-Ying ZY Hamann Mark T MT

Biochimica et biophysica acta 20120213 7

<h4>Background</h4>Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptors superfamily and are transcription factors activated by specific ligands. Liver X receptors (LXR) belong to the nuclear hormone receptors and have been shown to play an important role in cholesterol homeostasis. From the previous screening of several medicinal plants for potential partial PPARγ agonists, the extracts of Cornus alternifolia were found to exhibit promising bioactivity. In this pap ...[more]

PMID: 22353334

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Liver X receptor and peroxisome proliferator-activated receptor agonist from Cornus alternifolia.

Publications

Liver X receptor and peroxisome proliferator-activated receptor agonist from Cornus alternifolia.

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