title: Cytoprotective effect of rhamnetin on miconazole-induced H9c2 cell damage.
abstract: OBJECTIVE
  Reactive oxygen species (ROS) formation is closely related to miconazole-induced heart dysfunction. Although rhamnetin has antioxidant effects, it remained unknown whether it can protect against miconazole-induced cardiomyocyte apoptosis. Thus, we investigated the effects of rhamnetin on miconazole-stimulated H9c2 cell apoptosis.
  
  
  METHODS
  Cell morphology was observed by inverted microscope and cell viability was determined using a WelCount™ cell proliferation assay kit. Miconazole-induced ROS production was evaluated by fluorescence-activated cell sorting with 6-carboxy-2',7'-dichlorofluoroscein diacetate (H2DCF-DA) stain. Immunoblot analysis was used to determine apurinic/apyrimidinic endonuclease 1 (APE/Ref-1) and cleaved cysteine-aspartic protease (caspase) 3 expression. NADPH oxidase levels were measured using real-time polymerase chain reaction.
  
  
  RESULTS
  Miconazole (3 and 10 µM) induced abnormal morphological changes and cell death in H9c2 cells. Rhamnetin enhanced the viability of miconazole (3 µM)-treated cells in a dose-dependent manner. Rhamnetin (1 and 3 µM) treatment downregulated cleaved caspase 3 and upregulated APE/Ref-1 expression in miconazole-stimulated cells. Additionally, rhamnetin significantly reduced ROS generation.
  
  
  CONCLUSIONS
  Our data suggest that rhamnetin may have cytoprotective effects in miconazole-stimulated H9c2 cardiomyocytes via ROS inhibition. This effect most likely occurs through the upregulation of APE/Ref-1 and attenuation of hydrogen peroxide levels.
authors.affiliation: Department of Medical Science, School of Medicine, Konkuk University, Seoul 143-701, Korea.
authors.forename: Kang Pa
authors.initials: KP
authors.lastname: Lee
authors.affiliation: Department of Pathology, College of Korean Medicine, Dongguk University, Gyeonggi-Do 410-820, Korea.
authors.forename: Jai-Eun
authors.initials: JE
authors.lastname: Kim
authors.affiliation: Department of Diagnosis, College of Korean Medicine, Dongguk University, 32 Dongguk-ro, Ilsandong-gu, Goyang-si, Gyeonggi-Do 410-820, Korea.
authors.forename: Won-Hwan
authors.initials: WH
authors.lastname: Park
keywords: APE/Ref-1; Rhamnetin; apoptosis; cardiomyocyte; miconazole