Phosphodiesterase 4B (PDE4B) (PDE4B)

Phosphodiesterase 4B (PDE4B) is a member of the PDE4 family of enzymes that specifically hydrolyze cyclic adenosine monophosphate (cAMP), a critical second messenger involved in regulating various cellular processes (Source: UniProt Q07343). PDE4B is highly expressed in inflammatory cells, such as neutrophils, macrophages, and T-cells, as well as in specific regions of the brain (Source: PMID: 25613164). By controlling cAMP levels, PDE4B modulates the expression of pro-inflammatory and anti-inflammatory cytokines, making it a primary target for treating chronic inflammatory conditions like COPD, asthma, and psoriasis (Source: PubMed). In the central nervous system, PDE4B is implicated in the pathophysiology of schizophrenia and mood disorders, suggesting its potential as a target for cognitive enhancement and antidepressant therapy (Source: PMID: 15809331). Pharmacological inhibition of the PDE4B catalytic domain increases intracellular cAMP, which suppresses inflammatory signaling pathways; however, clinical utility is often hampered by dose-limiting side effects such as nausea and emesis, which are thought to be mediated by PDE4D inhibition or specific PDE4B isoforms in the area postrema (Source: StatPearls). Drugs like roflumilast and apremilast target the catalytic domain of PDE4B to exert their therapeutic effects, though achieving isoform selectivity remains a significant challenge in drug design (Source: DrugBank).

Other names

cAMP-specific 3',5'-cyclic phosphodiesterase 4BPDEIVBDPDE4Phosphodiesterase 4B, cAMP-specific

Inhibition of the catalytic activity of PDE4B prevents the hydrolysis of cyclic adenosine monophosphate (cAMP), leading to increased intracellular cAMP levels which subsequently activate protein kinase A (PKA) and suppress the production of pro-inflammatory cytokines and mediators (Source: DrugBank, PMID: 15809331).