Repurposing of the PDE5 inhibitor sildenafil for treatment of persistent pulmonary hypertension in neonates.

Repurposing of the PDE5 inhibitor sildenafil for treatment of persistent pulmonary hypertension in neonates. Curr Med Chem. 2020 Sep 23;: Authors: Poitras EL, Gust SL, Kerr PM, Plane F Abstract Nitric oxide (NO), an important endogenous signalling molecule released from vascular endothelial cells and nerves, activates the enzyme soluble guanylate cyclase to catalyze production of cyclic guanosine monophosphate (cGMP) from guanosine triphosphate. cGMP, in turn, activates protein kinase G to phosphorylate a range of effector proteins in smooth muscle cells that reduce intracellular Ca2+ levels to inhibit both contractility and proliferation. The enzyme phosphodiesterase type 5 (PDE5) curtails the actions of cGMP by hydrolyzing it into inactive 5'-GMP. Small molecule PDE5 inhibitors (PDE5is) such as sildenafil prolong the availability of cGMP and so enhance NO-mediated signalling. PDE5is are the first line treatment for erectile dysfunction but are also now approved for treatment of pulmonary arterial hypertension (PAH) in adults. Persistent pulmonary hypertension in neonates (PPHN) is currently treated with inhaled NO but this is an expensive option and around 1/3 of newborns are unresponsive resulting in the need for alternative approaches. Here we summarize the development, chemistry and pharmacology of PDE5is, the use of sildenafil for erectile dysfunction and PAH, and then critically review current evidence for the utility of furth...
Source: Current Medicinal Chemistry - Category: Chemistry Authors: Tags: Curr Med Chem Source Type: research