title: Inhibition of Intracellular Type 10 Adenylyl Cyclase Protects Cortical Neurons Against Reperfusion-Induced Mitochondrial Injury and Apoptosis.
abstract: Mitochondrial injury significantly contributes to the neuronal death under cerebral ischemia and reperfusion. Within several signaling pathways, cyclic adenosine monophosphate (cAMP) signaling plays a substantial role in mitochondrial injury and cell death. Traditionally, the source of cellular cAMP has been attributed to the membrane-bound adenylyl cyclase, whereas the role of the intracellular localized type 10 soluble adenylyl cyclase (sAC) in neuronal pathology has not been considered. Since neurons express an active form of sAC, we aimed to investigate the role of sAC in reperfusion-induced neuronal apoptosis. For this purpose, the in vitro model of oxygen/glucose deprivation (simulated ischemia, 1 h), followed by recovery (simulated reperfusion, 12 h) in rat embryonic neurons, was applied. Although ischemia alone had no significant effect on apoptosis, reperfusion led to an activation of the mitochondrial pathway of apoptosis, hallmarked by mitochondrial depolarization, cytochrome c release, and mitochondrial ROS formation. These effects were accompanied by significantly augmented sAC expression and increased cellular cAMP content during reperfusion. Pharmacological suppression of sAC during reperfusion reduced cellular cAMP and ameliorated reperfusion-induced mitochondrial apoptosis and ROS formation. Similarly, sAC knockdown prevented neuronal death. Further analysis revealed a role of protein kinase A (PKA), a major downstream target of sAC, in reperfusion-induced neuronal apoptosis and ROS formation. In conclusion, the results show a causal role of intracellular, sAC-dependent cAMP signaling in reperfusion-induced mitochondrial injury and apoptosis in neurons. The protective effect of sAC inhibition during the reperfusion phase provides a basis for the development of new strategies to prevent the reperfusion-induced neuronal injury.
authors.affiliation: Department of Molecular Medicine and Biotechnology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.|Department of Bioscience, Integral University, Lucknow, India.
authors.forename: Megha
authors.initials: M
authors.lastname: Chagtoo
authors.affiliation: Department of Endocrine Surgery, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Nelson
authors.initials: N
authors.lastname: George
authors.affiliation: Department of Bioscience, Integral University, Lucknow, India.
authors.forename: Neelam
authors.initials: N
authors.lastname: Pathak
authors.affiliation: Department of Molecular Medicine and Biotechnology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Swasti
authors.initials: S
authors.lastname: Tiwari
authors.affiliation: Department of Molecular Medicine and Biotechnology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Madan M
authors.initials: MM
authors.lastname: Godbole
authors.affiliation: Department of Clinical Pharmacology, Ruhr University Bochum, Bochum, Germany. yury.ladilov@rub.de.|Center for Cardiovascular Research, Charité-Mitte, Hessische Strasse 3-4, 10115, Berlin, Germany. yury.ladilov@rub.de.
authors.forename: Yury
authors.initials: Y
authors.lastname: Ladilov
mesh_terms: D000262:Adenylyl Cyclases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D015687:Cell Hypoxia / Q000502:physiology; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000201:enzymology* / Q000473:pathology; D019610:Cytoprotection / Q000502:physiology*; D055785:Gene Knockdown Techniques; D008928:Mitochondria / Q000201:enzymology* / Q000235:genetics; D009474:Neurons / Q000201:enzymology* / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000473:pathology
chemical_list: C579271:ADCY10 protein, human; D000262:Adenylyl Cyclases
keywords: Apoptosis; Bax; Ischemia/reperfusion; Protein kinase A; Soluble adenylyl cyclase