title: Chemopreventive effect of punicalagin, a novel tannin component isolated from Terminalia catappa, on H-ras-transformed NIH3T3 cells.
abstract: Terminalia catappa and its major tannin component, punicalagin, have been characterized to possess antioxidative and anti-genotoxic activities. However, their effects on reactive oxygen species (ROS) mediated carcinogenesis are still unclear. In the present study, H-ras-transformed NIH3T3 cells were used to evaluate the chemopreventive effect of T. catappa water extract (TCE) and punicalagin. In the cell proliferation assay, TCE and punicalagin suppressed the proliferation of H-ras-transformed NIH3T3 cells with a dose-dependent manner but only partially affected non-transformed NIH3T3 cells proliferation. The differential cytotoxicity of TCE/punicalagin on the H-ras-transformed and non-transformed NIH3T3 cells indicated the selectivity of TCE/punicalagin against H-ras induced transformation. TCE or punicalagin treatment reduced anchorage-independent growth that could be due to a cell cycle arrest at G0/G1 phase. The intracellular superoxide level, known to modulate downstream signaling of Ras protein, was decreased by punicalagin treatments. The levels of phosphorylated JNK-1 and p38 were also decreased with punicalagin treatments. Thus, the chemopreventive effect of punicalagin against H-ras induced transformation could result from inhibition of the intracellular redox status and JNK-1/p38 activation.
authors.affiliation: Department of Biotechnology, Chia Nan University of Phamacy and Science, Tainan, Taiwan, ROC.
authors.forename: Pin-Shern
authors.initials: PS
authors.lastname: Chen
authors.forename: Jih-Heng
authors.initials: JH
authors.lastname: Li
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D018890:Chemoprevention; D011905:Genes, ras / Q000235:genetics; D047348:Hydrolyzable Tannins / Q000494:pharmacology*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D041681:NIH 3T3 Cells; D010766:Phosphorylation / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism*; D017382:Reactive Oxygen Species; D029766:Terminalia / Q000737:chemistry*
chemical_list: D016588:Anticarcinogenic Agents; D047348:Hydrolyzable Tannins; D010936:Plant Extracts; D017382:Reactive Oxygen Species; C115642:punicalagin; D020928:Mitogen-Activated Protein Kinases; D016283:Proto-Oncogene Proteins p21(ras)