RRC ID 43419
Author Tamura T, Cui X, Sakaguchi N, Akashi M.
Title Ginsenoside Rd prevents and rescues rat intestinal epithelial cells from irradiation-induced apoptosis.
Journal Food Chem Toxicol
Abstract Panax ginseng has been shown to have a protective effect for irradiated animals or cells. Ginsenosides are the most active components isolated from ginseng, and ginsenoside Rd has been identified as one of the effective compounds responsible for the pharmaceutical actions of ginseng. In the present study, we studied the molecular mechanisms for the radio-protective action of ginsenoside Rd in rat intestinal epithelial IEC-6 cells. Cells were irradiated with gamma-ray, and apoptosis was examined using Hoechst staining and Western blot analysis. Treatment with ginsenoside Rd before gamma-irradiation inhibited irradiation-induced apoptosis in IEC-6 cells. Administration of Rd after irradiation also inhibited apoptosis in these cells. Irradiation of IEC-6 cells resulted in inactivation of Akt phosphorylation that was abrogated by Rd. On the other hand, irradiation activated phosphorylation of ERK1/2 but did not affect that of p38 MAPK. Inhibition of Akt phosphorylation prevented the reduction of apoptosis by Rd following irradiation. Pretreatment with an inhibitor of the MEK pathway further decreased the number of apoptotic cells. Rd decreased the ratios of Bax/Bcl-2 and Bax/Bcl-xL, the levels of cytochrome c, and the cleaved form of caspase-3 in irradiated IEC-6 cells. Our results suggest that ginsenoside Rd protects and rescues rat intestinal epithelial cells from irradiation-induced apoptosis through a pathway requiring activation of PI3K/Akt, inactivation of MEK, and also inhibition of a mitochondria/caspase pathway.
Volume 46(9)
Pages 3080-9
Published 2008-9
DOI 10.1016/j.fct.2008.06.011
PII S0278-6915(08)00299-8
PMID 18638517
MeSH Animals Apoptosis / drug effects* Apoptosis / radiation effects* Blotting, Western Caspase 3 / metabolism Cell Line Cytochromes c / metabolism Enzyme Inhibitors / pharmacology Epithelial Cells / drug effects* Epithelial Cells / radiation effects* Extracellular Signal-Regulated MAP Kinases / antagonists & inhibitors Ginsenosides / chemistry Ginsenosides / pharmacology* Indicators and Reagents Intestinal Mucosa / cytology Intestinal Mucosa / drug effects* Intestinal Mucosa / radiation effects* Phosphatidylinositol 3-Kinases / metabolism Phosphoinositide-3 Kinase Inhibitors Phosphorylation Proto-Oncogene Proteins c-akt / metabolism Radiation-Protective Agents* Rats Signal Transduction / drug effects bcl-2-Associated X Protein / metabolism bcl-X Protein / metabolism p38 Mitogen-Activated Protein Kinases / antagonists & inhibitors
IF 3.775
Times Cited 28
Human and Animal Cells