cAMP-specific 3',5'-cyclic phosphodiesterase (PDE4) (PDE4)

cAMP-specific 3',5'-cyclic phosphodiesterase (primarily the PDE4 family) is an enzyme class responsible for the hydrolysis of the second messenger cyclic adenosine monophosphate (cAMP) into its inactive form, 5'-adenosine monophosphate (5'-AMP) [1]. By regulating localized concentrations of cAMP, these enzymes serve as critical gatekeepers for intracellular signaling pathways that control inflammation, vascular tone, and neurotransmission [2]. PDE4 is the most therapeutically relevant member of this class and is highly expressed in inflammatory and immune cells such as neutrophils, macrophages, and T-lymphocytes [3]. Dysregulation of PDE4 activity is associated with various chronic inflammatory and autoimmune conditions, including chronic obstructive pulmonary disease (COPD), psoriasis, and atopic dermatitis [4]. Pharmacological inhibitors of these enzymes, such as roflumilast and apremilast, work by elevating intracellular cAMP levels, which subsequently activates protein kinase A (PKA) and suppresses the production of pro-inflammatory cytokines like TNF-alpha and IL-17 [5]. While effective, the clinical use of systemic PDE4 inhibitors is often limited by side effects such as nausea and emesis, which are thought to be mediated by the inhibition of specific PDE4 isoforms in the central nervous system [6]. Sources: [1] Francis SH, et al. (2011) Pharmacological Reviews; [2] Houslay MD. (2010) Nature Reviews Drug Discovery; [3] Giembycz MA. (2008) COPD; [4] Schafer P. (2014) Biochem Pharmacol; [5] Zhang KY, et al. (2005) Mol Pharmacol; [6] Robichaud A, et al. (2002) Neuropharmacology.

Other names

PDE4PDE7PDE8Phosphodiesterase 4Phosphodiesterase 7Phosphodiesterase 8cAMP-specific PDE3',5'-cyclic-AMP phosphodiesterase

Inhibition of the phosphodiesterase enzyme, specifically preventing the hydrolysis of cyclic adenosine monophosphate (cAMP) to 5'-AMP, thereby increasing intracellular cAMP levels and modulating downstream signaling pathways like PKA and Epac.