title: Dietary soy isoflavone replacement improves detrusor overactivity of  ovariectomized rats with altered connexin-43 expression in the urinary bladder.
abstract: To evaluate the effects of dietary soy isoflavone on detrusor overactivity (DO) in ovariectomized (Ovx) rats and the association between these effects and expression of the gap junction protein, connexin-43, in the urinary bladder, and to discuss the usefulness of soy isoflavones for overactive bladder (OAB).
  
  
  METHODS
  In all, 24 (8-week-old) virgin female Sprague-Dawley rats were divided equally into four groups: sham operation with control diet (with no dietary soy isoflavones; Sham-CD), bilateral Ovx with CD (Ovx-CD), sham operation with soy isoflavone diet (Sham-ID), bilateral Ovx with soy ID (Ovx-ID). Cystometry was performed after the 4-week CD or ID in each group while awake. Quantitative reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemical and Western blot analyses were also performed to examine the expression of connexin-43 in each group.
  
  
  RESULTS
  In Ovx-CD rats, there were some significant changes in cystometry variables, including shortening of the intercontraction interval and an increased number of non-voiding contractions compared with Sham-CD rats (P < 0.05). These changes were significantly improved by 4-week soy isoflavone administration (Ovx-ID; P < 0.05). Quantitative RT-PCR, immunohistochemical and Western blot analyses showed that the expression level of connexin-43 mRNA and protein was significantly greater in the urinary bladder of Ovx-CD rats compared with Sham-CD rats. Soy isoflavone administration significantly reduced this increased expression (Ovx-ID).
  
  
  CONCLUSIONS
  Soy isoflavone replacement improved DO with alteration of the connexin-43 expression pattern in the urinary bladder of Ovx rats. Routine consumption of diet soy isoflavones may be a useful treatment to prevent and improve OAB.
authors.affiliation: Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Okada
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kojima
authors.forename: Shuzo
authors.initials: S
authors.lastname: Hamamoto
authors.forename: Kentaro
authors.initials: K
authors.lastname: Mizuno
authors.forename: Shoichi
authors.initials: S
authors.lastname: Sasaki
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Kohri
mesh_terms: D000818:Animals; D015153:Blotting, Western; D018031:Connexin 43 / Q000378:metabolism*; D005260:Female; D007529:Isoflavones / Q000627:therapeutic use*; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D030262:Soybean Proteins / Q000627:therapeutic use*; D053201:Urinary Bladder, Overactive / Q000178:diet therapy*
chemical_list: D018031:Connexin 43; D007529:Isoflavones; D030262:Soybean Proteins