title: Oral treatment with genistein reduces the expression of molecular and biochemical markers of inflammation in a rat model of chronic TNBS-induced colitis.
abstract: BACKGROUND
  Inflammatory bowel disease (IBD) in humans has a high incidence in Europe and the USA, whereas in East Asia, incidence has been historically low. The risk of IBD appears to increase in Asian immigrants adopting western lifestyles, suggesting a strong link of environmental/dietary factors in the development of IBD. Exposure to high levels of isoflavones such as genistein (Gen) in traditional East Asian diets has been associated with a decreased risk of developing breast cancer and may also be beneficial for the prevention of IBD.
  
  
  OBJECTIVE
  In this study, the effect of orally administered genistein on the inflammatory response in the TNBS-induced chronic colitis rat model was investigated.
  
  
  METHODS
  Eighteen male Wistar rats, aged 12 weeks, were randomized to one of three groups (n = 6). Two groups received a 2,4,6-trinitrobenzenesulfonic acid (TNBS) enema, then were treated daily by oral gavage with either Gen (100 mg/kg b.w.) or vehicle, for 14 days. The last group served as a control group, not receiving the TNBS enema. At the end of the 14 days, animals were killed and tissues collected. Molecular and biochemical inflammatory markers in the colon, specifically cyclooxygenase-2 (COX-2) and myeloperoxidase (MPO), were analyzed. In addition, to assess the efficacy of Gen treatment, relative wet weights of the accessory sexual organs, specifically prostate and the seminal vesicle, were compared between the groups treated or not with Gen.
  
  
  RESULTS
  Wet weights of both prostates and seminal vesicles were significantly (P < 0.01) reduced upon Gen administration. In the colon, expression of COX-2 mRNA and protein was reduced (P < 0.05) in the Gen treatment group, as compared to the control group, whereas there was no significant inhibitory effect of Gen on the expression of proliferating cell nuclear antigen. In Gen treated animals colon wet weight was not altered, however a decrease in MPO activity (P < 0.01) was seen.
  
  
  CONCLUSIONS
  These results may provide evidence that oral administration of Gen exerts beneficial anti-inflammatory effects in a rodent model of TNBS-induced chronic colitis. While the sample size of this study was small, it nevertheless might encourage the realization of larger blinded randomized controlled studies for the proof of concept.
authors.affiliation: Department of Molecular and Cellular Sports Medicine, German Sport University Cologne, IG I, 9. OG, Am Sportpark Müngersdorf, 50933, Cologne, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Seibel
authors.forename: Almut F
authors.initials: AF
authors.lastname: Molzberger
authors.forename: Torsten
authors.initials: T
authors.lastname: Hertrampf
authors.forename: Ute
authors.initials: U
authors.lastname: Laudenbach-Leschowski
authors.forename: Patrick
authors.initials: P
authors.lastname: Diel
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D003106:Colon / Q000201:enzymology / Q000473:pathology; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D004195:Disease Models, Animal; D019833:Genistein / Q000008:administration & dosage / Q000627:therapeutic use*; D005837:Genitalia, Male / Q000187:drug effects; D007249:Inflammation / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D009929:Organ Size; D009195:Peroxidase / Q000378:metabolism*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014302:Trinitrobenzenesulfonic Acid / Q000633:toxicity
chemical_list: D018809:Proliferating Cell Nuclear Antigen; D012333:RNA, Messenger; D014302:Trinitrobenzenesulfonic Acid; D019833:Genistein; D009195:Peroxidase; D051546:Cyclooxygenase 2