Sildenafil and Other Phosphodiesterase Inhibitors: Are They Good for the Brain Too?

Selective inhibitors of phosphodiesterase (PDE) enzymes that are specific to cyclic guanosine monophosphate (cGMP) demonstrate a broad range of effects on blood flow, skeletal muscle, and physiological processes. These inhibitors have also had a positive impact on dystrophin-deficient mice, a model of Duchenne muscular dystrophy (DMD). Approximately 20% to 30% of boys with some variants of DMD display autism spectrum disorder (ASD) neurobehavioral deficits, and some impaired social behaviors in ASD have been associated with developmental deficits in cerebellar circuitry, including Purkinje cells, which highly express dystrophin.

In an industry-supported study, researchers explored potential effects of inhibitors of PDE5A (sildenafil [Viagra]…