Modulation of the heat-induced activation of mitogen-activated protein (MAP) kinase by quercetin.
Effects of quercetin, a bioflavonoid compound, on heat-induced activation of mitogen-activated protein (MAP) kinase in rat hepatoma (H4) cells were examined. Quercetin decreased cell viability and induced DNA fragmentation in heat-shocked H4 cells. MAP kinase in heat-shocked cells was activated and reached a peak at 1 hr after the heat shock, and then gradually decreased. Quercetin inhibited the heat-induced activation of MAP kinase observed at 1 hr after heat shock, but markedly stimulated MAP kinase activity at 4 hr after heat shock. Thus, quercetin modulated the heat-induced activation of MAP kinase in a biphasic manner. Present observations indicate that quercetin modulates protein phosphorylation, especially that controled by MAP kinase, in early events of heat shock response.
Nagasaka
Y
Y
Department of Nutrition, Yamaguchi Prefectural University, Japan. nagasaka@ws1.yamaguchi-pu.ac.jp
Nakamura
K
K
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002470:Cell Survival / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D004789:Enzyme Activation; D006360:Heat-Shock Proteins / Q000096:biosynthesis; D006358:Hot Temperature; D019319:Okadaic Acid / Q000494:pharmacology; D011794:Quercetin / Q000494:pharmacology*; D051381:Rats; D014407:Tumor Cells, Cultured
D006360:Heat-Shock Proteins; D019319:Okadaic Acid; D011794:Quercetin; D017871:Calcium-Calmodulin-Dependent Protein Kinases