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Title: Gypenoside XLIX, a naturally occurring gynosaponin, PPAR-alpha dependently inhibits LPS-induced tissue factor expression and activity in human THP-1 monocytic cells

Abstract

Tissue factor (TF) is involved not only in the progression of atherosclerosis and other cardiovascular diseases, but is also associated with tumor growth, metastasis, and angiogenesis and hence may be an attractive target for directed cancer therapeutics. Gynostemma pentaphyllum (GP) is widely used in the treatment of various cardiovascular diseases including atherosclerosis, as well as cancers. Gypenoside (Gyp) XLIX, a dammarane-type glycoside, is one of the prominent components in GP. We have recently reported Gyp XLIX to be a potent peroxisome proliferator-activated receptor (PPAR)-alpha activator. Here we demonstrate that Gyp XLIX (0-300 {mu}M) concentration dependently inhibited TF promoter activity after induction by the inflammatory stimulus lipopolysaccharide (LPS) in human monocytic THP-1 cells transfected with promoter reporter constructs pTF-LUC. Furthermore, Gyp XLIX inhibited LPS-induced TF mRNA and protein overexpression in THP-1 monocyte cells. Its inhibition of LPS-induced TF hyperactivity was further confirmed by chromogenic enzyme activity assay. The activities of Gyp XLIX reported in this study were similar to those of Wy-14643, a potent synthetic PPAR-alpha activator. Furthermore, the Gyp XLIX-induced inhibitory effect on TF luciferase activity was completely abolished in the presence of the PPAR-alpha selective antagonist MK-886. The present findings suggest that Gyp XLIX inhibits LPS-induced TF overexpression andmore » enhancement of its activity in human THP-1 monocytic cells via PPAR-alpha-dependent pathways. The data provide new insights into the basis of the use of the traditional Chinese herbal medicine G. pentaphyllum for the treatment of cardiovascular and inflammatory diseases, as well as cancers.« less

Authors:
 [1];  [1];  [1];  [2]
  1. Faculty of Pharmacy, University of Sydney, NSW 2006 (Australia)
  2. Faculty of Pharmacy, University of Sydney, NSW 2006 (Australia). E-mail: yuhao@pharm.usyd.edu.au
Publication Date:
OSTI Identifier:
20976835
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 218; Journal Issue: 1; Other Information: DOI: 10.1016/j.taap.2006.10.013; PII: S0041-008X(06)00373-5; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ALBUMINS; ARTERIOSCLEROSIS; CATTLE; CHINA; DRUGS; EDTA; ENZYME ACTIVITY; GLYCOSIDES; HUMAN POPULATIONS; INFLAMMATION; INHIBITION; LUCIFERASE; MEDICINE; METASTASES; MONOCYTES; NEOPLASMS; POLYMERASE CHAIN REACTION; PROMOTERS; RECEPTORS; SODIUM; SULFATES; TRANSCRIPTION

Citation Formats

Huang, Tom Hsun-Wei, Van Hoan Tran, Roufogalis, Basil D., and Li Yuhao. Gypenoside XLIX, a naturally occurring gynosaponin, PPAR-alpha dependently inhibits LPS-induced tissue factor expression and activity in human THP-1 monocytic cells. United States: N. p., 2007. Web. doi:10.1016/j.taap.2006.10.013.
Huang, Tom Hsun-Wei, Van Hoan Tran, Roufogalis, Basil D., & Li Yuhao. Gypenoside XLIX, a naturally occurring gynosaponin, PPAR-alpha dependently inhibits LPS-induced tissue factor expression and activity in human THP-1 monocytic cells. United States. doi:10.1016/j.taap.2006.10.013.
Huang, Tom Hsun-Wei, Van Hoan Tran, Roufogalis, Basil D., and Li Yuhao. Mon . "Gypenoside XLIX, a naturally occurring gynosaponin, PPAR-alpha dependently inhibits LPS-induced tissue factor expression and activity in human THP-1 monocytic cells". United States. doi:10.1016/j.taap.2006.10.013.
@article{osti_20976835,
title = {Gypenoside XLIX, a naturally occurring gynosaponin, PPAR-alpha dependently inhibits LPS-induced tissue factor expression and activity in human THP-1 monocytic cells},
author = {Huang, Tom Hsun-Wei and Van Hoan Tran and Roufogalis, Basil D. and Li Yuhao},
abstractNote = {Tissue factor (TF) is involved not only in the progression of atherosclerosis and other cardiovascular diseases, but is also associated with tumor growth, metastasis, and angiogenesis and hence may be an attractive target for directed cancer therapeutics. Gynostemma pentaphyllum (GP) is widely used in the treatment of various cardiovascular diseases including atherosclerosis, as well as cancers. Gypenoside (Gyp) XLIX, a dammarane-type glycoside, is one of the prominent components in GP. We have recently reported Gyp XLIX to be a potent peroxisome proliferator-activated receptor (PPAR)-alpha activator. Here we demonstrate that Gyp XLIX (0-300 {mu}M) concentration dependently inhibited TF promoter activity after induction by the inflammatory stimulus lipopolysaccharide (LPS) in human monocytic THP-1 cells transfected with promoter reporter constructs pTF-LUC. Furthermore, Gyp XLIX inhibited LPS-induced TF mRNA and protein overexpression in THP-1 monocyte cells. Its inhibition of LPS-induced TF hyperactivity was further confirmed by chromogenic enzyme activity assay. The activities of Gyp XLIX reported in this study were similar to those of Wy-14643, a potent synthetic PPAR-alpha activator. Furthermore, the Gyp XLIX-induced inhibitory effect on TF luciferase activity was completely abolished in the presence of the PPAR-alpha selective antagonist MK-886. The present findings suggest that Gyp XLIX inhibits LPS-induced TF overexpression and enhancement of its activity in human THP-1 monocytic cells via PPAR-alpha-dependent pathways. The data provide new insights into the basis of the use of the traditional Chinese herbal medicine G. pentaphyllum for the treatment of cardiovascular and inflammatory diseases, as well as cancers.},
doi = {10.1016/j.taap.2006.10.013},
journal = {Toxicology and Applied Pharmacology},
number = 1,
volume = 218,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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