Phosphodiesterase 4B (PDE4B)

Phosphodiesterase 4B (PDE4B) is a key enzyme belonging to the type IV, cyclic AMP (cAMP)-specific, cyclic nucleotide phosphodiesterase family. It is crucial for regulating cellular cAMP concentrations by hydrolyzing cAMP, thus impacting various signal transduction pathways. PDE4B has a modular structure with UCR1, UCR2, catalytic, ERK specificity, and KIM domains. It exists in multiple isoforms (long, short, super-short, dead-short) due to differential splicing and promoter usage. Its activity is regulated by dimerization and phosphorylation by PKA and ERK. PDE4B plays vital roles in neurological functions (cognition, memory, neuroplasticity), neuroinflammation, immune regulation, and mediating cellular responses. Altered PDE4B activity has been implicated in psychiatric disorders (schizophrenia, bipolar disorder), cognitive dysfunction, neuroinflammation, inflammatory diseases, and cancer. It is considered an attractive therapeutic target, with inhibitors like Rolipram and Crisaborole developed. The development of selective inhibitors is challenging due to the conserved active site across PDE4 subtypes, although targeting regions outside the active site, such as the CR3 region, is being explored to achieve selectivity.

Other names

Phosphodiesterase 4B

Inhibition of cyclic AMP (cAMP) hydrolysis, thereby increasing intracellular cAMP levels and influencing downstream signaling pathways.