title: Novel phosphodiesterase-5 (PDE5) inhibitors in the alleviation of erectile dysfunction due to diabetes and ageing-induced oxidative stress.
abstract: BACKGROUND
  Diabetes and ageing are associated with erectile dysfunction (ED). Under these conditions, increased oxidative stress produces superoxide ions, which in turn suppresses the nitric oxide-cyclic guanosine monophosphate pathway. The phophodiesterase-5 (PDE5) inhibitors still remain ineffective in 15 - 57% of impotent men.
  
  
  OBJECTIVE
  To identify the efficacy of conventional and novel PDE5 inhibitors on oxidative stress involved in diabetes and ageing.
  
  
  METHODS
  An electronic search of the literature was conducted to review published information relating diabetes and ageing to ED and to cover late-stage developments of novel PDE5 inhibitors.
  
  
  CONCLUSIONS
  Safe and more efficacious alternatives that can modulate PDE5 levels in ED regarding oxidative stress conditions are needed. Included in this review are updates on the new PDE5 inhibitors avanafil, udenafil, SLx-2101, and mirodenafil.
authors.affiliation: Tulane University Health Sciences Center, Department of Urology, 1430 Tulane Avenue, SL-42, New Orleans, LA 70112, USA.
authors.forename: Serap
authors.initials: S
authors.lastname: Gur
authors.forename: Suresh C
authors.initials: SC
authors.lastname: Sikka
authors.forename: Wayne J G
authors.initials: WJ
authors.lastname: Hellstrom
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D002986:Clinical Trials as Topic / Q000706:statistics & numerical data; D006152:Cyclic GMP / Q000502:physiology; D048909:Diabetes Complications / Q000188:drug therapy* / Q000201:enzymology / Q000209:etiology; D004353:Drug Evaluation, Preclinical; D007172:Erectile Dysfunction / Q000188:drug therapy* / Q000201:enzymology / Q000209:etiology; D006801:Humans; D008297:Male; D009569:Nitric Oxide / Q000502:physiology; D018384:Oxidative Stress / Q000187:drug effects; D010100:Oxygen / Q000097:blood / Q000502:physiology; D058986:Phosphodiesterase 5 Inhibitors; D010726:Phosphodiesterase Inhibitors / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D011817:Rabbits; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D014665:Vasodilator Agents / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D058986:Phosphodiesterase 5 Inhibitors; D010726:Phosphodiesterase Inhibitors; D017382:Reactive Oxygen Species; D014665:Vasodilator Agents; D009569:Nitric Oxide; D006152:Cyclic GMP; D010100:Oxygen