Effects of hydrogen sulfide on erectile function and its possible mechanism(s) of action

IntroductionThe current pharmacotherapy for erectile dysfunction (ED) relies significantly on the use of phosphodiesterase type 5 (PDE5) inhibitors, but quite a proportion of ED patients are resistant to this therapy, necessitating a search for an alternative treatment. We reviewed available published data to analyze current evidence of hydrogen sulfide (H₂S) as a novel pharmacotherapeutic agent with supportive role in sexual function.AimTo discuss the role of H₂S in erectile function, its possible mechanism of action, and how this knowledge may be exploited for therapeutic use.MethodsPubmed and Medline search was conducted to identify original articles and reviews.Main Outcome MeasuresData from peer‐reviewed publications.ResultsAnimal studies using different species, including in vitro study done in humans, show evidence of H₂S's pro‐erectile effects. The mechanism behind is still unclear, but evidence in literature points out the involvement of K⁺_ATP channel, modulation of protein with anti‐erectile effects, as well as involvement of the nitrergic pathway through a complex cross‐talk. A new drug called H₂S‐donating sildenafil (ACS6), which incorporated an H₂S‐donating moiety in sildenafil, has been developed. While more studies are still needed, this heralded a new pharmacotherapeutical approach, which is multipronged in nature.ConclusionsGiven the mounting evidence of H₂S's role in erectile function and how it appears to achieve its pro‐erectile effects through different mechanisms, H₂S represents a potentially important treatment alternative or adjunct to PDE5 inhibitors. Liaw RL, Srilatha B, and Adaikan PG. Effects of hydrogen sulfide on erectile function and its possible mechanism(s) of action. J Sex Med 2011;8:1853–1864.