title: Puerarin Suppresses Angiotensin II-Induced Cardiac Hypertrophy by Inhibiting NADPH Oxidase Activation and Oxidative Stress-Triggered AP-1 Signaling Pathways.
abstract: OBJECTIVE
  To examine the effects of puerarin (Pue) on angiotensin II (AngII)-induced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation and oxidative stress-related signaling pathways in the hypertrophic response of cardiomyocytes.
  
  
  METHODS
  Primary cardiomyocytes of neonatal C57BL/6J mice were pretreated with Pue (50, 100 μmol/L) and were then stimulated with AngII 1 μmol/L. NADPH oxidase activity and reactive oxygen species (ROS) levels were measured by lucigenin-enhanced chemiluminescence assay and flow cytometry. Western blotting was used to detect the distribution of the oxidase subunits, extracellular signal-regulated kinase (ERK1/2) and c-jun N-terminal kinase (JNK1/2) activation, and an electrophoretic mobility shift assay (EMSA) was performed to analyze the DNA binding activity of activator protein-1 (AP-1). Adult C57BL/6J mice were infused with AngII and were administered with Pue (100, 200 mg·kg-1·d-1) for 15 d. After the treatment, systolic blood pressure (SBP) and left ventricular wall thickness were examined. The ratios of heart weight to body weight (HW/BW) and left ventricular weight to body weight (LVW/BW) were measured, and heart morphometry was assessed.
  
  
  RESULTS
  In vitro, Pue dose-dependently blocked the phosphorylation of ERK1/2 and JNK1/2 and eventually abolished AP-1 binding activity through the inhibition of ROS production. Further studies revealed that AngII treatment resulted in increased NADPH oxidase activity, which was suppressed by Pue via the disruption of Rac1 activation and membrane translocation of oxidase subunits. In vivo, Pue attenuated cardiac hypertrophy, as evaluated by decreased HW/BW, LVW/BW, myocyte surface area, and left ventricular wall thickness.
  
  
  CONCLUSIONS
  The anti-hypertrophic mechanism of Pue occurred by blocking Rac1-dependent NADPH oxidase activation and downstream redox-sensitive AP-1 signaling pathways.
authors.affiliation: Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Gang
authors.forename: Cao
authors.initials: C
authors.lastname: Qiang
authors.forename: Cui
authors.initials: C
authors.lastname: Xiangli
authors.forename: Pan
authors.initials: P
authors.lastname: Shifen
authors.forename: Shen
authors.initials: S
authors.lastname: Chong
authors.forename: Liu
authors.initials: L
authors.lastname: Lihong
mesh_terms: D000804:Angiotensin II / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D006332:Cardiomegaly / Q000188:drug therapy* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D007529:Isoflavones / Q000008:administration & dosage / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D013329:Structure-Activity Relationship; D018808:Transcription Factor AP-1 / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D007529:Isoflavones; D017382:Reactive Oxygen Species; D018808:Transcription Factor AP-1; D000804:Angiotensin II; D019255:NADPH Oxidases; C033607:puerarin