Cyclic-AMP phosphodiesterase 4D (PDE4D)

Cyclic-AMP phosphodiesterase 4D (PDE4D) is an enzyme highly expressed in human tissues, especially within the brain, where it hydrolyzes cAMP—a second messenger regulating diverse physiological pathways[6][4][5]. PDE4D is part of a four-member PDE4 gene family (PDE4A-D) characterized by conserved UCR1 and UCR2 domains, and it exists in numerous isoforms generated by alternative splicing[2][1]. By modulating cAMP levels, PDE4D influences neuronal signaling, cognitive function, cell proliferation, and various hormone responses[5][2]. Pathogenic mutations in PDE4D cause genetic disorders like acrodysostosis, while aberrant expression or activity is implicated in memory impairment, depression, inflammatory pathologies, and cancer proliferation[3][5]. Inhibition of PDE4D enhances cAMP signaling, offering potential therapies for neurodegeneration, inflammation, and certain cancers, though tolerability can be a therapeutic challenge due to central and peripheral side effects such as emesis[4][5][6].

Other names

Phosphodiesterase 4DcAMP-specific 3',5'-cyclic phosphodiesterase 4DPDE4D7 (represents a key isoform)Phosphodiesterase type 4DPDE IV-D

Inhibitors increase intracellular cAMP (by preventing its degradation) Modulation of downstream effectors (e.g., PKA, CREB, MAPKs) Regulation of inflammatory cytokines Facilitation of neuroplasticity and memory by enhanced cAMP signaling