期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2015
卷号：112
期号：17
页码：E2253-E2262
DOI：10.1073/pnas.1416230112
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceBy catalyzing the destruction of cAMP and cGMP, cyclic nucleotide phosphodiesterases (PDEs) regulate their intracellular concentrations and biological actions. Eleven distinct gene families (PDE1-PDE11) define the PDE superfamily. Most families contain several PDE genes. Two separate but related genes generate PDE3 subfamilies PDE3A and PDE3B. Although inhibition of PDE3 protects rodent heart against ischemia/reperfusion (I/R) injury, the specific PDE3 isoform involved is undetermined. Using PDE3A- and PDE3B-KO mice, we report that deletion of PDE3B, but not PDE3A, protected mouse heart from I/R injury in vivo and in vitro, via cAMP-induced preconditioning. To our knowledge, our study is the first to define a role for PDE3B in cardioprotection against I/R injury and suggests PDE3B as a target for cardiovascular therapies. Although inhibition of cyclic nucleotide phosphodiesterase type 3 (PDE3) has been reported to protect rodent heart against ischemia/reperfusion (I/R) injury, neither the specific PDE3 isoform involved nor the underlying mechanisms have been identified. Targeted disruption of PDE3 subfamily B (PDE3B), but not of PDE3 subfamily A (PDE3A), protected mouse heart from I/R injury in vivo and in vitro, with reduced infarct size and improved cardiac function. The cardioprotective effect in PDE3B-/- heart was reversed by blocking cAMP-dependent PKA and by paxilline, an inhibitor of mitochondrial calcium-activated K channels, the opening of which is potentiated by cAMP/PKA signaling. Compared with WT mitochondria, PDE3B-/- mitochondria were enriched in antiapoptotic Bcl-2, produced less reactive oxygen species, and more frequently contacted transverse tubules where PDE3B was localized with caveolin-3. Moreover, a PDE3B-/- mitochondrial fraction containing connexin-43 and caveolin-3 was more resistant to Ca2+-induced opening of the mitochondrial permeability transition pore. Proteomics analyses indicated that PDE3B-/- heart mitochondria fractions were enriched in buoyant ischemia-induced caveolin-3-enriched fractions (ICEFs) containing cardioprotective proteins. Accumulation of proteins into ICEFs was PKA dependent and was achieved by ischemic preconditioning or treatment of WT heart with the PDE3 inhibitor cilostamide. Taken together, these findings indicate that PDE3B deletion confers cardioprotective effects because of cAMP/PKA-induced preconditioning, which is associated with the accumulation of proteins with cardioprotective function in ICEFs. To our knowledge, our study is the first to define a role for PDE3B in cardioprotection against I/R injury and suggests PDE3B as a target for cardiovascular therapies.
关键词：PDE3B−/− mice ; protein kinase A ; ischemia/reperfusion injury ; signalosome ; membrane repair
