title: Cofilin Inhibition Restores Neuronal Cell Death in Oxygen-Glucose Deprivation Model of Ischemia.
abstract: Ischemia is a condition associated with decreased blood supply to the brain, eventually leading to death of neurons. It is associated with a diverse cascade of responses involving both degenerative and regenerative mechanisms. At the cellular level, the changes are initiated prominently in the neuronal cytoskeleton. Cofilin, a cytoskeletal actin severing protein, is known to be involved in the early stages of apoptotic cell death. Evidence supports its intervention in the progression of disease states like Alzheimer's and ischemic kidney disease. In the present study, we have hypothesized the possible involvement of cofilin in ischemia. Using PC12 cells and mouse primary cultures of cortical neurons, we investigated the potential role of cofilin in ischemia in two different in vitro ischemic models: chemical induced oxidative stress and oxygen-glucose deprivation/reperfusion (OGD/R). The expression profile studies demonstrated a decrease in phosphocofilin levels in all models of ischemia, implying stress-induced cofilin activation. Furthermore, calcineurin and slingshot 1L (SSH) phosphatases were found to be the signaling mediators of the cofilin activation. In primary cultures of cortical neurons, cofilin was found to be significantly activated after 1 h of OGD. To delineate the role of activated cofilin in ischemia, we knocked down cofilin by small interfering RNA (siRNA) technique and tested the impact of cofilin silencing on neuronal viability. Cofilin siRNA-treated neurons showed a significant reduction of cofilin levels in all treatment groups (control, OGD, and OGD/R). Additionally, cofilin siRNA-reduced cofilin mitochondrial translocation and caspase 3 cleavage, with a concomitant increase in neuronal viability. These results strongly support the active role of cofilin in ischemia-induced neuronal degeneration and apoptosis. We believe that targeting this protein mediator has a potential for therapeutic intervention in ischemic brain injury and stroke.
authors.affiliation: Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, 3000 Arlington Avenue, Toledo, OH, 43614, USA.
authors.forename: Anusha
authors.initials: A
authors.lastname: Madineni
authors.affiliation: Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, 3000 Arlington Avenue, Toledo, OH, 43614, USA.|Ministry of Health, Diyala Health Directorate, Baqubah, Iraq.
authors.forename: Qasim
authors.initials: Q
authors.lastname: Alhadidi
authors.affiliation: Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, 3000 Arlington Avenue, Toledo, OH, 43614, USA. zahoor.shah@utoledo.edu.
authors.forename: Zahoor A
authors.initials: ZA
authors.lastname: Shah
mesh_terms: D051339:Actin Depolymerizing Factors / Q000378:metabolism*; D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology*; D019703:Calcineurin / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D016923:Cell Death; D002470:Cell Survival / Q000187:drug effects; D002540:Cerebral Cortex / Q000473:pathology; D015536:Down-Regulation / Q000187:drug effects; D055785:Gene Knockdown Techniques; D005947:Glucose / Q000172:deficiency*; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D008954:Models, Biological; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D018384:Oxidative Stress / Q000187:drug effects; D010100:Oxygen / Q000378:metabolism*; D016716:PC12 Cells; D010766:Phosphorylation / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D051381:Rats; D015854:Up-Regulation / Q000187:drug effects; D014638:Vanadates / Q000494:pharmacology
chemical_list: D051339:Actin Depolymerizing Factors; D014638:Vanadates; D019703:Calcineurin; D053148:Caspase 3; D005947:Glucose; D010100:Oxygen
keywords: Caspase 3; Cofilin; Ischemia; Oxygen–glucose deprivation; Reperfusion