Calycosin-7-O-β-D-glucoside promotes oxidative stress-induced cytoskeleton reorganization through integrin-linked kinase signaling pathway in vascular endothelial cells.
BACKGROUND
Dysfunction of vascular endothelium is implicated in many pathological situations. Cytoskeleton plays an importance role in vascular endothelial permeability barrier and inflammatory response. Many Chinese herbs have the endothelial protective effect, of which, "Astragalus membranaceus" is a highly valued herb for treatment of cardiovascular and renal diseases in traditional Chinese medicine, In this study, we tested whether calycosin-7-O-β-D-glucoside (Calycosin), a main effective monomer component of "Astragalus membranaceus", could protect endothelial cells from bacterial endotoxin (LPS)-induced cell injury.


METHODS
Endothelial cell injury was induced by exposing human umbilical vein endothelial cells (HUVECs) to LPS. The effects of calycosin on LPS-induced changes in cell viability, apoptosis rate, cell migration, nitric oxide synthase (NOS), generationof intracellular reactive oxygen species (ROS) and cytoskeleton organization were determined. Microarray assay was employed to screen the possible gene expression change. Based on the results of microarray assay, the expression profile of genes involved in Rho/ROCK pathway and AKT pathway were further evaluated with quantitative real-time RT-PCR or western blot methods.


RESULTS
Calycosin improved cell viability, suppressed apoptosis and protected the cells from LPS-induced reduction in cell migration and generation of ROS, protein level of NOS at a comparable magnitude to that of Y27632 and valsartan. Similar to Y27632 and valsartan, Calycosin, also neutralized LPS-induced actomyosin contraction and vinculin protein aggregation. Microarray assay, real-time PCR and western blot results revealed that LPS induced expression of FN, ITG A5, RhoA, PI3K (or PIP2 in western blotting), FAK, VEGF and VEGF R2, and inhibited expression of MLCP. We believed multiple pathways involved in the regulation of calycosin on HUVECs. Calycosin are considered to be able to activate MLCP through promoting the generation of NO, decreasing PMLC, suppressing the cytoskeleton remodeling caused by activation of Rho/ROCK pathway and inhibiting AKT pathway by decreasing VEGF, VEGF R2 and PI3K level.


CONCLUSIONS
Calycosin protected HUVEC from LPS-induced endothelial injury, possibly through suppression of Rho/ROCK pathway and regulation of AKT pathway.
Affiliated Hospital of Shandong University of Traditional Chinese Medicine, West Wenhua road #42, Jinan, Shandong, 250011, PR China. jiang_yuehua@hotmail.com.
Yue-Hua
YH
Jiang
Jiangsu Province Hospital of Traditional Chinese Medicine, Nanjing, 210029, China. jssunwei@163.com.
Wei
W
Sun
Affiliated Hospital of Shandong University of Traditional Chinese Medicine, West Wenhua road #42, Jinan, Shandong, 250011, PR China. lweidw@163.com.
Wei
W
Li
Affiliated Hospital of Shandong University of Traditional Chinese Medicine, West Wenhua road #42, Jinan, Shandong, 250011, PR China. hhzhen969@163.com.
Hong-Zhen
HZ
Hu
Affiliated Hospital of Shandong University of Traditional Chinese Medicine, West Wenhua road #42, Jinan, Shandong, 250011, PR China. zhoule1221@163.com.
Le
L
Zhou
Affiliated Hospital of Shandong University of Traditional Chinese Medicine, West Wenhua road #42, Jinan, Shandong, 250011, PR China. jianghh@163.com.
Hui-Hui
HH
Jiang
Affiliated Hospital of Shandong University of Traditional Chinese Medicine, West Wenhua road #42, Jinan, Shandong, 250011, PR China. 1289791127@qq.com.
Jing-Xin
JX
Xu
D002478:Cells, Cultured; D003599:Cytoskeleton / Q000378:metabolism*; D005960:Glucosides / Q000378:metabolism*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007529:Isoflavones / Q000378:metabolism*; D018384:Oxidative Stress / Q000502:physiology*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D000099200:Scaffold Protein ILK
D005960:Glucosides; D007529:Isoflavones; D017346:Protein Serine-Threonine Kinases; D000099200:Scaffold Protein ILK; C526426:calycosin-7-O-beta-D-glucoside