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Full-Text Articles in Medical Anatomy
S-Glutathionylation Activates Stim1 And Alters Mitochondrial Homeostasis., Brian J Hawkins, Krishna M Irrinki, Karthik Mallilankaraman, Yu-Chin Lien, Youjun Wang, Cunnigaiper D Bhanumathy, Ramasamy Subbiah, Michael F Ritchie, Jonathan Soboloff, Yoshihiro Baba, Tomohiro Kurosaki, Suresh K Joseph, Donald L Gill, Muniswamy Madesh
S-Glutathionylation Activates Stim1 And Alters Mitochondrial Homeostasis., Brian J Hawkins, Krishna M Irrinki, Karthik Mallilankaraman, Yu-Chin Lien, Youjun Wang, Cunnigaiper D Bhanumathy, Ramasamy Subbiah, Michael F Ritchie, Jonathan Soboloff, Yoshihiro Baba, Tomohiro Kurosaki, Suresh K Joseph, Donald L Gill, Muniswamy Madesh
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
Oxidant stress influences many cellular processes, including cell growth, differentiation, and cell death. A well-recognized link between these processes and oxidant stress is via alterations in Ca(2+) signaling. However, precisely how oxidants influence Ca(2+) signaling remains unclear. Oxidant stress led to a phenotypic shift in Ca(2+) mobilization from an oscillatory to a sustained elevated pattern via calcium release-activated calcium (CRAC)-mediated capacitive Ca(2+) entry, and stromal interaction molecule 1 (STIM1)- and Orai1-deficient cells are resistant to oxidant stress. Functionally, oxidant-induced Ca(2+) entry alters mitochondrial Ca(2+) handling and bioenergetics and triggers cell death. STIM1 is S-glutathionylated at cysteine 56 in response to …
Selective Role For Superoxide In Insp3 Receptor-Mediated Mitochondrial Dysfunction And Endothelial Apoptosis., Muniswamy Madesh, Brian J Hawkins, Tatyana Milovanova, Cunnigaiper D Bhanumathy, Suresh K Joseph, Satish P Ramachandrarao, Kumar Sharma, Tomohiro Kurosaki, Aron B Fisher
Selective Role For Superoxide In Insp3 Receptor-Mediated Mitochondrial Dysfunction And Endothelial Apoptosis., Muniswamy Madesh, Brian J Hawkins, Tatyana Milovanova, Cunnigaiper D Bhanumathy, Suresh K Joseph, Satish P Ramachandrarao, Kumar Sharma, Tomohiro Kurosaki, Aron B Fisher
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
Reactive oxygen species (ROS) play a divergent role in both cell survival and cell death during ischemia/reperfusion (I/R) injury and associated inflammation. In this study, ROS generation by activated macrophages evoked an intracellular Ca2+ ([Ca2+]i) transient in endothelial cells that was ablated by a combination of superoxide dismutase and an anion channel blocker. [Ca2+]i store depletion, but not extracellular Ca2+ chelation, prevented [Ca2+]i elevation in response to O2*- that was inositol 1,4,5-trisphosphate (InsP3) dependent, and cells lacking the three InsP3 receptor (InsP3R) isoforms failed to display the [Ca2+]i transient. Importantly, the O2*--triggered Ca2+ mobilization preceded a loss in mitochondrial membrane …
Functionally Active T1-T1 Interfaces Revealed By The Accessibility Of Intracellular Thiolate Groups In Kv4 Channels., Guangyu Wang, Mohammad Shahidullah, Carmen A Rocha, Candace Strang, Paul J Pfaffinger, Manuel Covarrubias
Functionally Active T1-T1 Interfaces Revealed By The Accessibility Of Intracellular Thiolate Groups In Kv4 Channels., Guangyu Wang, Mohammad Shahidullah, Carmen A Rocha, Candace Strang, Paul J Pfaffinger, Manuel Covarrubias
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
Gating of voltage-dependent K(+) channels involves movements of membrane-spanning regions that control the opening of the pore. Much less is known, however, about the contributions of large intracellular channel domains to the conformational changes that underlie gating. Here, we investigated the functional role of intracellular regions in Kv4 channels by probing relevant cysteines with thiol-specific reagents. We find that reagent application to the intracellular side of inside-out patches results in time-dependent irreversible inhibition of Kv4.1 and Kv4.3 currents. In the absence or presence of Kv4-specific auxiliary subunits, mutational and electrophysiological analyses showed that none of the 14 intracellular cysteines is …
Vdac-Dependent Permeabilization Of The Outer Mitochondrial Membrane By Superoxide Induces Rapid And Massive Cytochrome C Release., M Madesh, György Hajnóczky
Vdac-Dependent Permeabilization Of The Outer Mitochondrial Membrane By Superoxide Induces Rapid And Massive Cytochrome C Release., M Madesh, György Hajnóczky
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
Enhanced formation of reactive oxygen species (ROS), superoxide (O2*-), and hydrogen peroxide (H2O2) may result in either apoptosis or other forms of cell death. Here, we studied the mechanisms underlying activation of the apoptotic machinery by ROS. Exposure of permeabilized HepG2 cells to O2*- elicited rapid and massive cytochrome c release (CCR), whereas H2O2 failed to induce any release. Both O2*- and H2O2 promoted activation of the mitochondrial permeability transition pore by Ca2+, but Ca2+-dependent pore opening was not required for O2*--induced CCR. Furthermore, O2*- alone evoked CCR without damage of the inner mitochondrial membrane barrier, as mitochondrial membrane potential …
Eliciting The Low-Activity Aldehyde Dehydrogenase Asian Phenotype By An Antisense Mechanism Results In An Aversion To Ethanol., E Garver, Tu Gc, Q N Cao, M Aini, F Zhou, Y Israel
Eliciting The Low-Activity Aldehyde Dehydrogenase Asian Phenotype By An Antisense Mechanism Results In An Aversion To Ethanol., E Garver, Tu Gc, Q N Cao, M Aini, F Zhou, Y Israel
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
A mutation in the gene encoding for the liver mitochondrial aldehyde dehydrogenase (ALDH2-2), present in some Asian populations, lowers or abolishes the activity of this enzyme and results in elevations in blood acetaldehyde upon ethanol consumption, a phenotype that greatly protects against alcohol abuse and alcoholism. We have determined whether the administration of antisense phosphorothioate oligonucleotides (ASOs) can mimic the low-activity ALDH2-2 Asian phenotype. Rat hepatoma cells incubated for 24 h with an antisense oligonucleotide (ASO-9) showed reductions in ALDH2 mRNA levels of 85% and ALDH2 (half-life of 22 h) activity of 55% equivalent to a >90% inhibition in ALDH2 …