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Updated: May 28, 2025

Fluorescence-based Monitoring of PAD4 Activity via a Pro-fluorescence Substrate Analog
Published on: November 5, 2014
Molecular Properties of Phosphodiesterase 4 and Its Inhibition by Roflumilast and Cilomilast
Hyun Jeong Kwak1, Ki Hyun Nam2
1Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Republic of Korea.
Abstract:
Phosphodiesterase 4 (PDE4) catalyzes cyclic adenosine monophosphate (cAMP) hydrolysis, playing a crucial role in the cAMP signaling pathway. cAMP is a secondary messenger involved in numerous physiological functions, such as inflammatory responses, immune responses, neural activity, learning, and memory. PDE4 inhibition is important for controlling anti-inflammatory and neuroprotective effects. In this review, we provide a comprehensive overview of the molecular functions and properties of human PDE4s. The study presents detailed sequence information for the PDE4 isoforms and the structural properties of the catalytic domain in members of the PDE4 family. We also review the inhibitory effects of the PDE4 inhibitors roflumilast and cilomilast related to respiratory diseases in PDE4. The crystal structures of PDE4 in complex with roflumilast and cilomilast are also analyzed. This review provides useful information for the future design of novel PDE4 inhibitors.
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