Fig. 5.

The cAMP cascades involved in PDE4 inhibition.

Reproduced from Ref. [48], with permission from MDPI (Basel, Switzerland). 5′AMP 5-adenosine monophosphate, AC adenylyl cyclase, ATF-1 cAMP-dependent activating transcription factor 1, ATP adenosine triphosphate, Bcl-6 B cell lymphoma 6 protein, cAMP 3′,5′-cyclic adenosine monophosphate, CREB cAMP response element binding protein, Epac 1/2 exchange protein directly activated by cAMP 1 and 2, NF-κB nuclear factor kappa light chain enhancer of activated B cells, PDE4 phosphodiesterase 4, PDE4-I phosphodiesterase 4 inhibitor, PKA protein kinase A, Popeye Popeye domain family, Rac1 Ras-related C3 botulinum toxin substrate 1, Rap 1 Ras-related protein 1, RhoA Ras homolog family member A