title: Honokiol, a constituent of Magnolia species, inhibits adrenergic contraction of human prostate strips and induces stromal cell death.
abstract: OBJECTIVE
  Smooth muscle contraction and prostate growth are important targets for medical therapy of lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia. Honokiol and Magnolol are lignan constituents of Magnolia species, which are used in traditional Asian medicine. Here, we examined effects of honokiol and magnolol on contraction of human prostate tissue and on growth of stromal cells.
  
  
  METHODS
  Prostate tissues were obtained from radical prostatectomy. Contraction of prostate strips was examined in organ bath studies. Effects in stromal cells were assessed in cultured immortalized human prostate stromal cells (WPMY-1). Ki-67 mRNA was assessed by reverse transcription-polymerase chain reaction, and proliferation by a fluorescence 5-ethynyl-2'-deoxyuridine assay.
  
  
  RESULTS
  Honokiol (100μM) reduced noradrenaline-induced contractions, which was significant at 10 to 100μM noradrenaline. Honokiol reduced phenylephrine-induced contractions, which was significant at 3 to 100μM phenylephrine. Honokiol reduced electric field stimulation-induced contractions very slightly. In WPMY-1 cells, honokiol (24 hours) induced cell death. Magnolol (100μM) was without effects on contraction, and cellular viability.
  
  
  CONCLUSIONS
  Honokiol inhibits smooth muscle contraction in the human prostate, and induces cell death in cultured stromal cells. Because prostate smooth muscle tone and prostate growth may cause LUTS, it appears possible that honokiol improves voiding symptoms.
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Herrmann
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Schreiber
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Ciotkowska
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Strittmatter
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Raphaela
authors.initials: R
authors.lastname: Waidelich
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Christian G
authors.initials: CG
authors.lastname: Stief
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Gratzke
authors.affiliation: Department of Urology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Hennenberg
keywords: Adrenergic alpha-1 receptors; Honokiol; Lower urinary tract symptoms; Magnolia; Prostatic hyperplasia