PDE4A and Alzheimer disease: Underscoring the importance of PDE4 inhibitors in disease, the PDE4 inhibitor rolipram has been reported to have potential as a neuroprotectant, as well as enhance cognition and rescue memory deficits in models of Huntington’s disease, Alzheimer’s disease, diabetes, or following brain injury (DeMarch et al., 2008, Burgin et al., 2010, Cheng et al., 2010, Miao et al., 2015, Titus et al., 2013).