scholarly journals Engineering of Saposin C Protein Chimeras for Enhanced Cytotoxicity and Optimized Liposome Binding Capability

Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 583
Author(s):  
Suzanne I. Sandin ◽  
David M. Gravano ◽  
Christopher J. Randolph ◽  
Meenakshi Sharma ◽  
Eva de Alba
Keyword(s):  
Cell Death ◽  
Lipid Binding ◽  
Solution Nmr ◽  
Small Peptides ◽  
C Protein ◽  
Saposin C ◽  
Bh3 Domain ◽  
Peripheral Membrane Protein ◽  
A Cell ◽  
Physiological Values

Saposin C (sapC) is a lysosomal, peripheral-membrane protein displaying liposome fusogenic capabilities. Proteoliposomes of sapC and phosphatidylserine have been shown to be toxic for cancer cells and are currently on clinical trial to treat glioblastoma. As proof-of-concept, we show two strategies to enhance the applications of sapC proteoliposomes: (1) Engineering chimeras composed of sapC to modulate proteoliposome function; (2) Engineering sapC to modify its lipid binding capabilities. In the chimera design, sapC is linked to a cell death-inducing peptide: the BH3 domain of the Bcl-2 protein PUMA. We show by solution NMR and dynamic light scattering that the chimera is functional at the molecular level by fusing liposomes and by interacting with prosurvival Bcl-xL, which is PUMA’s known mechanism to induce cell death. Furthermore, sapC-PUMA proteoliposomes enhance cytotoxicity in glioblastoma cells compared to sapC. Finally, the sapC domain of the chimera has been engineered to optimize liposome binding at pH close to physiological values as protein–lipid interactions are favored at acidic pH in the native protein. Altogether, our results indicate that the properties of sapC proteoliposomes can be modified by engineering the protein surface and by the addition of small peptides as fusion constructs.

Death by association: BH3 domain-only proteins and liver injury

2005 ◽  
Vol 289 (6) ◽  
pp. G987-G990 ◽  
Author(s):  
E. S. Baskin-Bey ◽  
G. J. Gores
Keyword(s):  
Cell Death ◽  
Liver Injury ◽  
Mitochondrial Dysfunction ◽  
Liver Cell ◽  
Liver Diseases ◽  
Chronic Liver Diseases ◽  
Concise Review ◽  
Bh3 Domain ◽  
A Cell

Apoptosis, a prominent form of cell death, is a prime feature of many acute and chronic liver diseases. Apoptosis requires mitochondrial dysfunction, which is regulated by proteins of the Bcl-2 family. Whether or not a cell should live or die is controlled by the interaction of multidomain Bcl-2 proteins with proapoptotic BH3 domain-only proteins of this family. Current models suggest multidomain, antiapoptotic Bcl-2 proteins prevent mitochondrial dysfunction by sequestering and/or preventing activation of its proapoptotic relatives. BH3-only proteins initiate cell death by neutralizing and or ligating multidomain prosurvival Bcl-2 proteins. Thus BH3 domain-only proteins are paramount in the apoptotic process as exemplified by the role of the BH3 domain-only protein Bid in liver injury. In this concise review, we will focus on how these BH3 domain-only proteins are regulated in the cell, their association with the Bcl-2 family of proteins, and finally, current information regarding their involvement in liver cell apoptosis and injury.

A Cell Death Pathway Induced by Antibody-Mediated Cross-Linking of CD45 on Lymphocytes

2003 ◽  
Vol 23 (5-6) ◽  
pp. 421-440 ◽  
Author(s):  
Ann-Muriel Steff ◽  
Marylene Fortin ◽  
Fabianne Philippoussis ◽  
Sylvie Lesage ◽  
Chantal Arguin ◽  
...  
Keyword(s):  
Cell Death ◽  
Cross Linking ◽  
Cell Death Pathway ◽  
A Cell

scholarly journals Mitochondria and Pharmacologic Cardiac Conditioning—At the Heart of Ischemic Injury

2021 ◽  
Vol 22 (6) ◽  
pp. 3224
Author(s):  
Christopher Lotz ◽  
Johannes Herrmann ◽  
Quirin Notz ◽  
Patrick Meybohm ◽  
Franz Kehl
Keyword(s):  
Cell Death ◽  
Mitochondrial Permeability Transition ◽  
Permeability Transition ◽  
Research Field ◽  
Calcium Handling ◽  
Control Mechanisms ◽  
Intrinsic Resistance ◽  
Atp Production ◽  
Cardiac Conditioning ◽  
A Cell

Pharmacologic cardiac conditioning increases the intrinsic resistance against ischemia and reperfusion (I/R) injury. The cardiac conditioning response is mediated via complex signaling networks. These networks have been an intriguing research field for decades, largely advancing our knowledge on cardiac signaling beyond the conditioning response. The centerpieces of this system are the mitochondria, a dynamic organelle, almost acting as a cell within the cell. Mitochondria comprise a plethora of functions at the crossroads of cell death or survival. These include the maintenance of aerobic ATP production and redox signaling, closely entwined with mitochondrial calcium handling and mitochondrial permeability transition. Moreover, mitochondria host pathways of programmed cell death impact the inflammatory response and contain their own mechanisms of fusion and fission (division). These act as quality control mechanisms in cellular ageing, release of pro-apoptotic factors and mitophagy. Furthermore, recently identified mechanisms of mitochondrial regeneration can increase the capacity for oxidative phosphorylation, decrease oxidative stress and might help to beneficially impact myocardial remodeling, as well as invigorate the heart against subsequent ischemic insults. The current review highlights different pathways and unresolved questions surrounding mitochondria in myocardial I/R injury and pharmacological cardiac conditioning.

scholarly journals Hypoxic neuronal necrosis: Protein synthesis-independent activation of a cell death program

2003 ◽  
Vol 100 (5) ◽  
pp. 2825-2830 ◽  
Author(s):  
J. Niquet ◽  
R. A. Baldwin ◽  
S. G. Allen ◽  
D. G. Fujikawa ◽  
C. G. Wasterlain
Keyword(s):  
Cell Death ◽  
Protein Synthesis ◽  
Neuronal Necrosis ◽  
Cell Death Program ◽  
A Cell

scholarly journals Identification of Selenoprotein P Fragments as a Cell-Death Inhibitory Factor

2003 ◽  
Vol 26 (6) ◽  
pp. 794-798 ◽  
Author(s):  
Masaki Hirashima ◽  
Takeshi Naruse ◽  
Hiroaki Maeda ◽  
Chikateru Nozaki ◽  
Yoshiro Saito ◽  
...  
Keyword(s):  
Cell Death ◽  
Inhibitory Factor ◽  
Selenoprotein P ◽  
A Cell

Increased cell death in osteopontin-deficient cardiac fibroblasts occurs by a caspase-3-independent pathway

2004 ◽  
Vol 287 (4) ◽  
pp. H1730-H1739 ◽  
Author(s):  
Ron Zohar ◽  
Baoqian Zhu ◽  
Peter Liu ◽  
Jaro Sodek ◽  
C. A. McCulloch
Keyword(s):  
Cell Death ◽  
Caspase 3 ◽  
Cardiac Fibroblasts ◽  
Chromatin Condensation ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Tunel Staining ◽  
Wild Type ◽  
Nuclear Fragmentation ◽  
A Cell

Reperfusion-induced oxidative injury to the myocardium promotes activation and proliferation of cardiac fibroblasts and repair by scar formation. Osteopontin (OPN) is a proinflammatory cytokine that is upregulated after reperfusion. To determine whether OPN enhances fibroblast survival after exposure to oxidants, cardiac fibroblasts from wild-type (WT) or OPN-null (OPN−/−) mice were treated in vitro with H2O2to model reperfusion injury. Within 1 h, membrane permeability to propidium iodide (PI) was increased from 5 to 60% in OPN−/−cells but was increased to only 20% in WT cells. In contrast, after 1–8 h of treatment with H2O2, the percent of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-stained cells was more than twofold higher in WT than OPN−/−cells. Electron microscopy of WT cells treated with H2O2showed chromatin condensation, nuclear fragmentation, and cytoplasmic and nuclear shrinkage, which are consistent with apoptosis. In contrast, H2O2-treated OPN−/−cardiac fibroblasts exhibited cell and nuclear swelling and membrane disruption that are indicative of cell necrosis. Treatment of OPN−/−and WT cells with a cell-permeable caspase-3 inhibitor reduced the percentage of TUNEL staining by more than fourfold in WT cells but decreased staining in OPN−/−cells by ∼30%. Although the percentage of PI-permeable WT cells was reduced threefold, the percent of PI-permeable OPN−/−cells was not altered. Restoration of OPN expression in OPN−/−fibroblasts reduced the percentage of PI-permeable cells but not TUNEL staining after H2O2treatment. Thus H2O2-induced cell death in OPN-deficient cardiac fibroblasts is mediated by a caspase-3-independent, necrotic pathway. We suggest that the increased expression of OPN in the myocardium after reperfusion may promote fibrosis by protecting cardiac fibroblasts from cell death.

scholarly journals Chronic Social Stress and Ethanol Increase Expression of KLF11, a Cell Death Mediator, in Rat Brain

2015 ◽  
Vol 28 (1) ◽  
pp. 18-31 ◽  
Author(s):  
Jeremy Duncan ◽  
Niping Wang ◽  
Xiao Zhang ◽  
Shakevia Johnson ◽  
Sharonda Harris ◽  
...  
Keyword(s):  
Cell Death ◽  
Rat Brain ◽  
Social Stress ◽  
Chronic Social Stress ◽  
A Cell

The Fas ligand as a cell death factor and signal transducer

2003 ◽  
Vol 3 (12) ◽  
pp. 33-46 ◽  
Author(s):  
Andreas Linkermann ◽  
Jing Qian ◽  
Dieter Kabelitz ◽  
Ottmar Janssen
Keyword(s):  
Cell Death ◽  
Fas Ligand ◽  
Signal Transducer ◽  
A Cell

scholarly journals Macrophage Autophagy and Oxidative Stress: An Ultrastructural and Immunoelectron Microscopical Study

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Ida Perrotta ◽  
Valentina Carito ◽  
Emilio Russo ◽  
Sandro Tripepi ◽  
Saveria Aquila ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Programmed Cell Death ◽  
Defense Mechanisms ◽  
Ultrastructural Localization ◽  
Microscopical Study ◽  
Beclin 1 ◽  
Cell Organelles ◽  
A Cell ◽  
First Time

The word autophagy broadly refers to the cellular catabolic processes that lead to the removal of damaged cytosolic proteins or cell organelles through lysosomes. Although autophagy is often observed during programmed cell death, it may also serve as a cell survival mechanism. Accumulation of reactive oxygen species within tissues and cells induces various defense mechanisms or programmed cell death. It has been shown that, besides inducing apoptosis, oxidative stress can also induce autophagy. To date, however, the regulation of autophagy in response to oxidative stress remains largely elusive and poorly understood. Therefore, the present study was designed to examine the ratio between oxidative stress and autophagy in macrophages after oxidant exposure (AAPH) and to investigate the ultrastructural localization of beclin-1, a protein essential for autophagy, under basal and stressful conditions. Our data provide evidence that oxidative stress induces autophagy in macrophages. We demonstrate, for the first time by immunoelectron microscopy, the subcellular localization of beclin-1 in autophagic cells.

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