benzyloxycarbonylvalyl-alanyl-aspartyl-fluoromethyl-ketone and Disease-Models--Animal

Necroptotic cell death is characterized by an activation of RIPK3 and MLKL that leads to plasma membrane permeabilization and the release of immunostimulatory cellular contents. High levels of chondrocyte death occur following intra-articular trauma, which frequently leads to post-traumatic osteoarthritis development. The aim of this study is to assess necroptosis levels in cartilage post-trauma and to examine whether chondrocyte necroptotic mechanisms may be investigated and modified in vitro. Fractured human and murine cartilage, analysed immunohistochemically for necroptosis marker expression, demonstrated significantly higher levels of RIPK3 and phospho-MLKL than uninjured controls. Primary murine chondrocytes stimulated in vitro with the TNFα and AKT-inhibitor alongside the pan-caspase inhibitor Z-VAD-fmk exhibited a significant loss of metabolic activity and viability, accompanied by an increase in MLKL phosphorylation, which was rescued by further treatment of chondrocytes with necrostatin-1. Transmission electron microscopy demonstrated morphological features of necroptosis in chondrocytes following TNFα and Z-VAD-fmk treatment. Release of dsDNA from necroptotic chondrocytes was found to be significantly increased compared to controls. This study demonstrates that cartilage trauma leads to a high prevalence of necroptotic chondrocyte death, which can be induced and inhibited in vitro, indicating that both necroptosis and its consequential release of immunostimulatory cellular contents are potential therapeutic targets in post-traumatic arthritis treatment.

Topics: Amino Acid Chloromethyl Ketones; Animals; Cell Survival; Cells, Cultured; Chondrocytes; Disease Models, Animal; Humans; Imidazoles; Indoles; Intra-Articular Fractures; Mice; Necroptosis; Phosphorylation; Primary Cell Culture; Protein Kinases; Receptor-Interacting Protein Serine-Threonine Kinases; Tumor Necrosis Factor-alpha

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis Inducing Factor; Autophagy; Beclin-1; Blotting, Western; Caspase Inhibitors; Cytoprotection; Disease Models, Animal; Drug Combinations; Immunosuppressive Agents; Injections, Intraocular; Male; Microscopy, Electron, Transmission; Microtubule-Associated Proteins; Necroptosis; Protein Serine-Threonine Kinases; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Receptor-Interacting Protein Serine-Threonine Kinases; Retina; Retinal Detachment; Sirolimus

Necroptosis contributes to ischemia-induced brain injury. Tumor necrosis factor (TNF) receptor associated factor 2 (TRAF2) has been reported to suppress necroptotic cell death under several pathological conditions. In this study, we investigated the role of TRAF2 in experimental stroke using a mouse middle cerebral artery occlusion (MCAO) model and in vitro cellular models. TRAF2 expression in the ischemic brain was assessed with western blot and real-time RT-PCR. Gene knockdown of TRAF2 by lentivirus was utilized to investigate the role of TRAF2 in stroke outcomes. The expression of TRAF2 was significantly induced in the ischemic brain at 24 h after reperfusion, and neurons and microglia were two of the cellular sources of TRAF2 induction. Striatal knockdown of TRAF2 increased infarction size, cell death, microglial activation and the expression of pro-inflammatory markers at 24 h after reperfusion. TRAF2 expression and necroptosis were induced in mouse primary microglia treated with conditioned medium collected from neurons subject to oxygen and glucose deprivation (OGD) and in TNFα-treated mouse hippocampal neuronal HT-22 cells in the presence of the pan-caspase inhibitor Z-VAD. In addition, TRAF2 knockdown exacerbated microglial cell death and neuronal cell death under these conditions. Moreover, pre-treatment with a specific necroptosis inhibitor necrostatin-1 (nec-1) suppressed the cell death exacerbated by TRAF2 knockdown in the brain following MCAO, indicating that TRAF2 impacted ischemic brain damage through necroptosis mechanism. Taken together, our results demonstrate that TRAF2 is a novel regulator of cerebral ischemic injury.

Topics: Amino Acid Chloromethyl Ketones; Animals; Brain; Cell Hypoxia; Cells, Cultured; Culture Media, Conditioned; Disease Models, Animal; GTPase-Activating Proteins; Infarction, Middle Cerebral Artery; Male; Mice; Mice, Inbred ICR; Microglia; Necroptosis; Protein Kinases; Reperfusion Injury; RNA Interference; RNA, Small Interfering; TNF Receptor-Associated Factor 2; Tumor Necrosis Factor-alpha

Topics: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; Amino Acid Chloromethyl Ketones; Animals; Apoptosis Inducing Factor; Caspase 1; Caspase 7; Cell Death; Cell Line, Tumor; Disease Models, Animal; Dopaminergic Neurons; Down-Regulation; Enzyme Activation; Humans; Mice, Knockout; Models, Biological; Motor Activity; Parkinson Disease; Poly(ADP-ribose) Polymerases

To elucidate the role of reactive oxygen species (ROS) in arthritis and to identify targets of arthritis treatment in conditions with different levels of oxidant stress.. Through establishing an arthritis model by injecting arthritogenic serum into wild-type and NADPH oxidase 2 (NOX2)-deficient mice, we found that arthritis had a neutrophilic infiltrate and was more severe in Ncf1(-/-) mice, a mouse strain lacking the expression of the NCF1/p47(phox) component of NOX2. The levels of interleukin-1β (IL-1β) and IL-6 in inflamed joints were higher in Ncf1(-/-) than in controls. Antagonists of tumor necrosis factor-α (TNFα) and IL-1β were equally effective in suppressing arthritis in wild-type mice, while IL-1β blockade was more effective than TNFα blockade in Ncf1(-/-) mice. A treatment of caspase inhibitor and the combination treatment of a caspase inhibitor and a cathepsin inhibitor, but not a cathepsin inhibitor alone, suppressed arthritic severity in the wild-type mice, while a treatment of cathepsin inhibitor and the combination treatment of a caspase inhibitor and a cathepsin inhibitor, but not a caspase inhibitor alone, were effective in treating Ncf1(-/-) mice. Consistently, cathepsin B was found to proteolytically process pro-IL-1β to its active form and this activity was suppressed by ROS.. This novel mechanism of a redox-mediated immune regulation of arthritis through leukocyte-produced ROS is important for devising an optimal treatment for patients with different levels of tissue ROS.. Our results suggest that ROS act as a negative feedback to constrain IL-1β-mediated inflammation, accounting for the more severe arthritis in the absence of NOX2.

Topics: Amino Acid Chloromethyl Ketones; Animals; Ankle Joint; Arthritis; Caspase Inhibitors; Cathepsin B; Cell Line; Cytokines; Dipeptides; Disease Models, Animal; Fibroblasts; Humans; Inflammation; Interleukin-1beta; Ketones; Lung; Membrane Glycoproteins; Mice, Inbred C57BL; Mice, Inbred NOD; Mice, Knockout; NADPH Oxidase 2; NADPH Oxidases; Oxidation-Reduction; Reactive Oxygen Species; Wrist Joint

DBA/2J mice are characterized by early onset hearing loss at about 3-4 weeks of age. Mutations in cadherin 23 (Cdh23) and fascin-2 (Fscn2) are responsible for the phenotypes, but the underlying mechanism is unknown. In the present study, DBA/2J mice displayed progressive hair cell loss and degeneration of spiral ganglion neurons (SGNs) after 2 weeks of age; however, the mRNA level of Caspase-3 in the inner ears was much higher at 2 weeks of age than that at 4 or 8 weeks of age. Moreover, transcriptional levels of Caspase-3 and Caspase-9 in the inner ears of DBA/2J mice were significantly higher than those of C57BL/6J mice at 2 or 8 weeks of age. Immunohistochemistry localized Caspase-3 and Caspase-9 mainly to the hair cells, SGNs and stria vascularis of the cochleae. To determine the significance of caspase-dependent apoptosis in the hearing loss, the pan-caspase inhibitor Z-VAD-FMK was given intraperitoneally to DBA/J2 mice over an 8-week period starting at one week of age. Blockage of caspases preserved hearing in the mice by more than 10 dB (dB) sound pressure level (SPL) of the ABR thresholds and significantly reduced outer hair cell loss at the basal turns of the cochleae. These results demonstrate that apoptosis in the cochleae of DBA/J2 mice contributes to the early onset of hearing loss, which can be attenuated by anti-apoptotic treatment.

Topics: Acoustic Stimulation; Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Auditory Threshold; Caspase 3; Caspase 9; Caspase Inhibitors; Cochlea; Cytoprotection; Disease Models, Animal; Drug Administration Schedule; Evoked Potentials, Auditory, Brain Stem; Gene Expression Regulation; Genotype; Hearing Loss; Injections, Intraperitoneal; Mice, Inbred C57BL; Mice, Inbred DBA; Otoacoustic Emissions, Spontaneous; Phenotype; Time Factors

The pathogenesis of non-alcoholic steatohepatitis (NASH) is not fully understood. In the present study, both in vitro and in vivo vimentin expression and secretion in NASH were investigated. The exposure of palmitate and lipopolysaccharide (LPS) to HepG2 cells enhanced caspase-3 activity and vimentin expression, respectively. The combined effects of both treatments on vimentin expression and caspase-3 activation appeared to be synergic. In contrast, blockade of caspase-3 activity by zVADfmk resulted in a significant reduction of cleaved vimentin and secreted vimentin into the culture supernatant. Similarly, lipid accumulation and inflammation occurred in mice fed a methionine-choline-deficient diet; thus, vimentin expression and serum cleaved vimentin levels were increased. However, vimentin was not significantly upregulated, and no cleavage occurred in mice fed a high-fat diet. It was conclusively determined that lipid accumulation in hepatocytes induces apoptosis through a caspase-3 dependent pathway; whereas, LPS stimulates vimentin expression, leading to its cleavage and secretion. Increased vimentin fragment levels indicated the existence of substantial hepatocellular death via an apoptotic mechanism.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Caspase 3; Diet; Disease Models, Animal; Disease Progression; Hep G2 Cells; Humans; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Palmitates; Up-Regulation; Vimentin

Acute kidney injury (AKI) induced by renal ischemia is a common clinical problem associated with a high morbidity and mortality. The present study investigated whether necroptosis was present in an in vitro renal ischemia model and whether the addition of necrostatin-1 (Nec-1) has a protective effect. In addition, whether autophagy was inhibited following the use of Nec-1 was also examined. When apoptosis was inhibited by z-VAD‑fmk and energy was depleted with antimycin A for 1 h, the morphological abnormalities of human proximal tubular epithelial (HK-2) cells were markedly attenuated, and the cell viability was significantly improved following incubation with Nec-1. LC3-II/I ratios and LC3-II/GAPDH ratios demonstrated a statistically significant decrease in the Nec-1 + tumor necrosis factor (TNF)-α + z-VAD-fmk + antimycin A (1 h) group compared with the control group. In conclusion, the present study suggested that necroptosis was present in HK-2 cells subjected to TNF-α stimulation and energy depletion. Nec-1 inhibits a caspase‑independent necroptotic pathway involving autophagy and may have therapeutic potential to prevent and treat renal ischemic injury.

Topics: Adenosine Triphosphate; Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Autophagy; Cell Line; Cell Survival; Disease Models, Animal; Epithelial Cells; Humans; Imidazoles; Indoles; Ischemia; Microtubule-Associated Proteins; Necrosis; Protective Agents; Tumor Necrosis Factor-alpha

A number of in vitro models of post-traumatic osteoarthritis (PTOA) have been developed to study the effect of mechanical overload on the processes that regulate cartilage degeneration. While such frameworks are critical for the identification therapeutic targets, existing technologies are limited in their throughput capacity. Here, we validate a test platform for high-throughput mechanical injury incorporating engineered cartilage.. We utilized a high-throughput mechanical testing platform to apply injurious compression to engineered cartilage and determined their strain and strain rate dependent responses to injury. Next, we validated this response by applying the same injury conditions to cartilage explants. Finally, we conducted a pilot screen of putative PTOA therapeutic compounds.. Engineered cartilage response to injury was strain dependent, with a 2-fold increase in glycosaminoglycan (GAG) loss at 75% compared to 50% strain. Extensive cell death was observed adjacent to fissures, with membrane rupture corroborated by marked increases in lactate dehydrogenase (LDH) release. Testing of established PTOA therapeutics showed that pan-caspase inhibitor [Z-VAD-FMK (ZVF)] was effective at reducing cell death, while the amphiphilic polymer [Poloxamer 188 (P188)] and the free-radical scavenger [N-Acetyl-L-cysteine (NAC)] reduced GAG loss as compared to injury alone.. The injury response in this engineered cartilage model replicated key features of the response of cartilage explants, validating this system for application of physiologically relevant injurious compression. This study establishes a novel tool for the discovery of mechanisms governing cartilage injury, as well as a screening platform for the identification of new molecules for the treatment of PTOA.

Topics: Acetylcysteine; Amino Acid Chloromethyl Ketones; Animals; Cartilage, Articular; Caspase Inhibitors; Cattle; Cell Death; Disease Models, Animal; Drug Evaluation, Preclinical; Glycosaminoglycans; High-Throughput Screening Assays; Materials Testing; Osteoarthritis; Pilot Projects; Poloxamer; Stress, Mechanical; Tissue Engineering

Pancreatic ductal adenocarcinoma (PDAC) represents the fourth leading cause of cancer death in the western world, with a 5-year survival rate below 5%. Murine double minute 2 (Mdm2) is an important negative regulator of the tumor suppressor p53. Reactivation of wild-type p53 is a promising treatment strategy, and inhibitors of Mdm2 have already entered clinical trials. To investigate the effects of Mdm2 inhibitors in PDAC, we used a murine cell line platform with a genetically defined status of p53. Here, we describe that Mdm2 inhibitors can act on a subset of murine PDAC cell lines p53 independently. Furthermore, we observed that Mdm2 inhibitors increase the sensitivity of murine PDAC cell lines toward topoisomerase II inhibitors by inducing effector caspase-independent cell death. The combination of Mdm2 inhibitors with topoisomerase II inhibitors acts independent of the survival factor NFκB/RelA. Mechanistically, Mdm2 inhibitors increase topoisomerase II inhibitor-induced DNA double-strand breaks. We show that Mdm2 binds to Nbs1 of the Mre11-Rad50-Nijmegen breakage syndrome (Nbs) 1 DNA repair complex. In addition, we provide evidence that Mdm2 inhibitors delay DNA repair. These findings may help to design novel therapeutic strategies to overcome therapeutic resistance of PDAC.

Topics: Amino Acid Chloromethyl Ketones; Animals; Antineoplastic Agents; Apoptosis; Blotting, Western; Cell Line, Tumor; Deoxycytidine; Disease Models, Animal; DNA Damage; Doxorubicin; Drug Synergism; Etoposide; Gemcitabine; Imidazoles; Immunohistochemistry; Immunoprecipitation; Indoles; Mice; Pancreatic Neoplasms; Piperazines; Proto-Oncogene Proteins c-mdm2; Pyrrolidinones; Topoisomerase II Inhibitors

Age-related macular degeneration (AMD) is the leading cause of registered blindness among the elderly and affects over 30 million people worldwide. It is well established that oxidative stress, inflammation, and apoptosis play critical roles in pathogenesis of AMD. In advanced wet AMD, although, most of the severe vision loss is due to bleeding and exudation of choroidal neovascularization (CNV), and it is well known that vascular endothelial growth factor (VEGF) plays a pivotal role in the growth of the abnormal blood vessels. VEGF suppression therapy improves visual acuity in AMD patients. However, there are unresolved issues, including safety and cost. Here we show that mice lacking c-Jun N-terminal kinase 1 (JNK1) exhibit decreased inflammation, reduced CNV, lower levels of choroidal VEGF, and impaired choroidal macrophage recruitment in a murine model of wet AMD (laser-induced CNV). Interestingly, we also detected a substantial reduction in choroidal apoptosis of JNK1-deficient mice. Intravitreal injection of a pan-caspase inhibitor reduced neovascularization in the laser-induced CNV model, suggesting that apoptosis plays a role in laser-induced pathological angiogenesis. Intravitreal injection of a specific JNK inhibitor decreased choroidal VEGF expression and reduced pathological CNV. These results suggest that JNK1 plays a key role in linking oxidative stress, inflammation, macrophage recruitment apoptosis, and VEGF production in wet AMD and pharmacological JNK inhibition offers a unique and alternative avenue for prevention and treatment of AMD.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Choroidal Neovascularization; Cysteine Proteinase Inhibitors; Cytokines; Disease Models, Animal; Humans; Inflammation Mediators; Macrophages; Macular Degeneration; Mice; Mice, Inbred C57BL; Mice, Knockout; Mitogen-Activated Protein Kinase 8; Oxidative Stress; Vascular Endothelial Growth Factor A

Autophagy is a dynamic and highly regulated process of self-digestion responsible for cell survival and reaction to oxidative stress. As oxidative stress is increased in uremia and is associated with vascular calcification, we studied the role of autophagy in vascular calcification induced by phosphate. In an in vitro phosphate-induced calcification model of vascular smooth muscle cells (VSMCs) and in an in vivo model of chronic renal failure, autophagy was inhibited by the superoxide dismutase mimic MnTMPyP, superoxide dismutase-2 overexpression, and by knockdown of the sodium-dependent phosphate cotransporter Pit1. Although phosphate-induced VSMC apoptosis was reduced by an inhibitor of autophagy (3-methyladenine) and knockdown of autophagy protein 5, calcium deposition in VSMCs was increased during inhibition of autophagy, even with the apoptosis inhibitor Z-VAD-FMK. An inducer of autophagy, valproic acid, decreased calcification. Furthermore, 3-methyladenine significantly promoted phosphate-induced matrix vesicle release with increased alkaline phosphatase activity. Thus, autophagy may be an endogenous protective mechanism counteracting phosphate-induced vascular calcification by reducing matrix vesicle release. Therapeutic agents influencing the autophagic response may be of benefit to treat aging or disease-related vascular calcification and osteoporosis.

Topics: Adenine; Alkaline Phosphatase; Amino Acid Chloromethyl Ketones; Animals; Antioxidants; Autophagy; Autophagy-Related Protein 5; Caspase Inhibitors; Cattle; Cells, Cultured; Disease Models, Animal; Kidney Failure, Chronic; Metalloporphyrins; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Phosphates; Proteins; Rats; RNA Interference; Secretory Vesicles; Sodium-Phosphate Cotransporter Proteins, Type III; Superoxide Dismutase; Time Factors; Transfection; Valproic Acid; Vascular Calcification

We report a novel mutation (erlong, erl) of the cadherin 23 (Cdh23) gene in a mouse model for DFNB12 characterized by progressive hearing loss beginning from postnatal day 27 (P27). Genetic and sequencing analysis revealed a 208 T >C transition causing an amino-acid substitution (70S-P). Caspase expression was upregulated in mutant inner ears. Hearing was preserved (up to 35-dB improvement) in pan-caspase inhibitor Z-VAD-FMK-treated mutants compared with untreated mutants (P<0.05). Outer hair cell (OHC) loss in the cochleae of Z-VAD-FMK-treated mutants was significantly reduced compared with those of untreated mice. Thus, the erl mutation can lead to hearing loss through apoptosis. This is the first genetic mouse model of hearing loss shown to respond to otoprotective drug therapy. The short interval from initial hearing loss to deafness (P27-P90) makes this model ideal for screening and validating otoprotective drugs.

Topics: Age Factors; Amino Acid Chloromethyl Ketones; Amino Acid Sequence; Animals; Cadherins; Disease Models, Animal; Drug Evaluation, Preclinical; Genetic Complementation Test; Hair Cells, Auditory, Outer; Hearing Loss; Mice; Mice, Inbred C3H; Mice, Inbred C57BL; Molecular Sequence Data; Neuroprotective Agents; Point Mutation

PURPOSE. To validate an established adult organotypic retinal explant culture system for use as an efficient medium-throughput screening tool to investigate novel retinal ganglion cell (RGC) neuroprotective therapies. METHODS. Optimal culture conditions for detecting RGC neuroprotection in rat retinal explants were identified. Retinal explants were treated with various recognized, or purported, neuroprotective agents and cultured for either 4 or 7 days ex vivo. The number of cells surviving in the RGC layer (RGCL) was quantified using histologic and immunohistochemical techniques, and statistical analyses were applied to detect neuroprotective effects. RESULTS. The ability to replicate previously reported in vivo RGC neuroprotection in retinal explants was verified by demonstrating that caspase inhibition, brain-derived neurotrophic factor treatment, and stem cell transplantation all reduced RGCL cell loss in this model. Further screening of potential neuroprotective pharmacologic agents demonstrated that betaxolol, losartan, tafluprost, and simvastatin all alleviated RGCL cell loss in retinal explants, supporting previous reports. However, treatment with brimonidine did not protect RGCL neurons from death in retinal explant cultures. Explants cultured for 4 days ex vivo proved most sensitive for detecting neuroprotection. CONCLUSIONS. The current adult rat retinal explant culture model offers advantages over other models for screening potential neuroprotective drugs, including maintenance of neurons in situ, control of environmental conditions, and dissociation from other factors such as intraocular pressure. Verification that neuroprotection by previously identified RGC-protective therapies could be replicated in adult retinal explant cultures suggests that this model could be used for efficient medium-throughput screening of novel neuroprotective therapies for retinal neurodegenerative disease.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Brain-Derived Neurotrophic Factor; Caspase Inhibitors; Cell Survival; Cells, Cultured; Coculture Techniques; Colforsin; Disease Models, Animal; Drug Evaluation, Preclinical; Male; Mesenchymal Stem Cells; Nerve Crush; Neuroprotective Agents; Ocular Hypertension; Optic Nerve; Optic Nerve Diseases; Organ Culture Techniques; Rats; Rats, Sprague-Dawley; Retinal Ganglion Cells; Stem Cell Transplantation

We recently demonstrated that molecular therapy using aminoglycosides can overcome the underlying genetic defect in two zebrafish models of ocular coloboma and showed abnormal cell death to be a key feature associated with the optic fissure closure defects. In further studies to identify molecular therapies for this common congenital malformation, we now examine the effects of anti-apoptotic compounds in zebrafish models of ocular coloboma in vivo.. Two ocular coloboma zebrafish lines (pax2.1/noi(tu29a) and lamb1/gup(m189)) were exposed to diferuloylmethane (curcumin) or benzyloxycarbonyl-Val-Ala-Asp(Ome)-fluoromethylketone (zVAD-fmk; a pan-caspase inhibitor) for up to 8 days post-fertilization. The effects of these compounds were assessed by morphology, histology, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and western blot analysis.. The size of the coloboma in gup zebrafish mutants treated with diferuloylmethane was greatly reduced. In treated mutants a reduction in TUNEL staining and a 67% decrease in activated caspase-3 protein were observed. The release of cytochrome c from the mitochondria into the cytosol was reduced fourfold by in vivo diferuloylmethane treatment, suggesting that the drug was acting to inhibit the intrinsic apoptotic pathway. Inhibition of caspases directly with zVAD-fmk also resulted in a similar reduction in coloboma phenotype. Treatment with either diferuloylmethane or zVAD-fmk resulted in a statistically significant 1.4 fold increase in length of survival of these mutant zebrafish (p<0.001), which normally succumb to the lethal genetic mutation. In contrast, the coloboma phenotype in noi zebrafish mutants did not respond to either diferuloylmethane or zVAD-fmk exposure, even though inhibition of apoptotic cell death was observed by a reduction in TUNEL staining.. The differential sensitivity to anti-apoptotic agents in lamb1-deficient and pax2.1-deficient zebrafish models, suggests that apoptotic cell death is not a final common pathway in all ocular coloboma genotypes. When considering anti-cell death therapies for ocular colobomatous defects attention should be paid to the genotype under investigation.

Topics: Amino Acid Chloromethyl Ketones; Animals; Blotting, Western; Caspase 3; Cell Death; Coloboma; Curcumin; Cytochromes c; Disease Models, Animal; Dose-Response Relationship, Drug; Embryo, Nonmammalian; Eye; Genetic Variation; In Situ Nick-End Labeling; Longevity; Mitochondria; Mutation; Phenotype; Zebrafish; Zebrafish Proteins

Neurogenic pulmonary edema (NPE) is a well-known complication of subarachnoid hemorrhage (SAH), which potentially causes a poor outcome. The aim of this study was to examine if NPE occurs in the endovascular perforation model of SAH in mice and if apoptosis contributes to NPE development after SAH in mice.. Sham-operated or SAH mice were treated with an intraperitoneal administration of vehicle or an antiapoptotic drug Z-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK) 1 h post-SAH. Pulmonary edema measurements and evaluation of apoptosis occurrence were performed on the lung at 24 h post-SAH.. SAH caused NPE, which was associated with apoptosis of pulmonary endothelial cells. Z-VAD-FMK significantly prevented apoptosis and NPE.. Pulmonary endothelial cell apoptosis contributes to the pathophysiology of NPE after SAH in mice.

Topics: Amino Acid Chloromethyl Ketones; Analysis of Variance; Animals; Apoptosis; Caspase 3; Disease Models, Animal; Endothelial Cells; In Situ Nick-End Labeling; Indoles; Lung; Mice; Neuroprotective Agents; Pulmonary Edema; Subarachnoid Hemorrhage; von Willebrand Factor

Bacterial meningitis causes persisting neurofunctional sequelae. Theoccurrence of apoptotic cell death in the hippocampal subgranular zone of the dentate gyrus characterizes the disease in patients and relates to deficits in learning and memory in corresponding experimental models. Here, we investigated why neurogenesis fails to regenerate the damage in the hippocampus associated with the persistence of neurofunctional deficits. In an infant rat model of bacterial meningitis, the capacity of hippocampal-derived cells to multiply and form neurospheres was significantly impaired comparedto that in uninfected littermates. In an in vitro model of differentiating hippocampal cells, challenges characteristic of bacterial meningitis (i.e. bacterial components, tumor necrosis factor [20 ng/mL], or growth factor deprivation) caused significantly more apoptosis in stem/progenitor cells and immature neurons than in mature neurons. These results demonstrate that bacterial meningitis injures hippocampal stem and progenitor cells, a finding that may explain the persistence of neurofunctional deficits after bacterial meningitis.

Topics: Amino Acid Chloromethyl Ketones; Analysis of Variance; Animals; Animals, Newborn; Annexin A5; Apoptosis; Cell Differentiation; Cells, Cultured; Collagen; Disease Models, Animal; Gene Expression Regulation; Hippocampus; Intercellular Signaling Peptides and Proteins; Meningitis, Bacterial; Nerve Tissue Proteins; Neural Stem Cells; Neurogenesis; Neurons; Neuroprotective Agents; Rats; Rats, Wistar; Time Factors; Tumor Necrosis Factor-alpha

Glycogen synthase kinase-3beta (GSK-3beta) is a crucial component in the cascade of events that culminate in a range of neurodegenerative diseases. It is controlled by several pathways, including calpain-mediated cleavage. Calpain mediates in cell death induced by 3-nitropropionic acid (3-NP), but GSK-3beta regulation has not been demonstrated. Here we studied changes in total GSK-3beta protein levels and GSK-3beta phosphorylation at Ser-9 in this model. The 3-NP treatment induced GSK-3beta truncation. This regulation was dependent on calpain activation, since addition of calpeptin to the medium prevented this cleavage. While calpain inhibition prevented 3-NP-induced neuronal loss, inhibition of GSK-3beta by SB-415286 did not. Furthermore, inhibition of cdk5, a known target of calpain involved in 3-NP-induced cell death, also failed to rescue neurons in our model. Our results point to a new target of calpain and indicate possible cross-talk between calpain and GSK-3beta in the 3-NP toxicity pathway. On the basis of our findings, we propose that calpain may modulate 3-NP-induced neuronal loss.

Topics: Amino Acid Chloromethyl Ketones; Aminophenols; Animals; Calpain; Caspases; Cell Survival; Cells, Cultured; Convulsants; Disease Models, Animal; Embryo, Mammalian; Enzyme Inhibitors; Gene Expression Regulation, Enzymologic; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Hippocampus; Male; Maleimides; Mice; Neurodegenerative Diseases; Neurons; Neuroprotective Agents; Nitro Compounds; Propionates; Purines; Rats; Roscovitine; Signal Transduction; Time Factors

A major challenge in the inner ear research field is to restore hearing loss of both non-genetic and genetic origin. A large effort is being made to protect hair cells from cell death after exposure to noise or drugs that can cause hearing loss. Our research focused on protecting hair cells from cell death occurring in a genetic model for human deafness. POU4F3 is a transcription factor associated with human hearing impairment. Pou4f3 knockout mice (Pou4f3(-/-)) have no cochlear hair cells, resulting in complete deafness. Although the hair cells appear to form properly, they progressively degenerate via apoptosis. In order to rescue the hair cells in the knockout mice, we produced explant cultures from mouse cochleae at an early embryonic stage and treated the cells with z-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), a general caspase inhibitor. Hair cell numbers in the knockout mice treated with z-VAD-fmk were significantly higher than in the untreated mice. We found that the time window that z-VAD-fmk has a protective effect is between E14.5 (P=0.001) to E16.5 (P=0.03), but not after E18.5. The source of the surviving hair cells is not due to proliferation, as measured by 5-bromo-2-deoxyuridine (BrdU) labeling, or to supporting cell transdifferentiation to hair cells, since there was no change in supporting cell numbers. Instead, the survival appears to be a direct effect of the anti-apoptotic agent on the dying hair cells with an early developmental window. These results help towards providing a comprehensive understanding of the molecular mechanisms of hair cell death, which might lead to the development of new therapeutic anti-apoptotic agents to alleviate hereditary hearing loss (HL).

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Cell Survival; Cochlea; Deafness; Disease Models, Animal; Hair Cells, Auditory, Inner; Homeodomain Proteins; Humans; Mice; Mice, Knockout; Neuroprotective Agents; Transcription Factor Brn-3C

Distant organ effects of acute kidney injury (AKI) are a leading cause of morbidity and mortality. While little is known about the underlying mechanisms, limited data suggest a role for inflammation and apoptosis. Utilizing a lung candidate gene discovery approach in a mouse model of ischemic AKI-induced lung dysfunction, we identified prominent lung activation of 66 apoptosis-related genes at 6 and/or 36 h following ischemia, of which 6 genes represent the tumor necrosis factor receptor (TNFR) superfamily, and another 23 genes are associated with the TNFR pathway. Given that pulmonary apoptosis is an important pathogenic mechanism of acute lung injury (ALI), we hypothesized that AKI leads to pulmonary proapoptotic pathways that facilitate lung injury and inflammation. Functional correlation with 1) terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling and 2) active caspase-3 (aC3) activity, immunoblotting, and immunohistochemistry (IHC) identified kidney IRI-induced pulmonary apoptosis at 24 h, and colocalization studies with CD34 identified predominantly endothelial apoptosis. Mice were treated with the caspase inhibitor Z-VAD-FMK (0.25 mg ip) or vehicle 1 h before and 8 h after sham or kidney IRI, and bronchoalveolar lavage fluid protein was measured at 36 h as a surrogate for lung leak. Caspase inhibition reduced lung microvascular changes after kidney IRI. The pulmonary apoptosis seen in wild-type control mice during AKI was absent in TNFR(-/-) mice. Using an initial genomic approach to discovery followed by a mechanistic approach to disease targeting, we demonstrate that pulmonary endothelial apoptosis is a direct mediator of the distant organ dysfunction during experimental AKI.

Topics: Acute Kidney Injury; Acute Lung Injury; Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Caspase 3; Caspase Inhibitors; Disease Models, Animal; Endothelium; Gene Expression Profiling; Lung; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Receptors, Tumor Necrosis Factor, Type I; Reperfusion Injury

Protein cleavage is a common feature in human neurodegenerative disease. Ataxin-3 protein with an expanded polyglutamine (polyQ) repeat causes spinocerebellar ataxia type-3 (SCA3), also called Machado-Joseph disease, and is cleaved in mammalian cells, transgenic mice and SCA3 patient brain tissue. However, the pathological significance of Ataxin-3 cleavage has not been carefully examined. To gain insight into the significance of Ataxin-3 cleavage, we developed a Drosophila SL2 cell-based model as well as transgenic fly models. Our data indicate that Ataxin-3 protein cleavage is conserved in the fly and may be caspase-dependent as reported previously. Importantly, comparison of flies expressing either wild-type or caspase-site mutant proteins indicates that Ataxin-3 cleavage enhances neuronal loss in vivo. This genetic in vivo confirmation of the pathological role of Ataxin-3 cleavage indicates that therapies targeting Ataxin-3 cleavage might slow disease progression in SCA3 patients.

Topics: Amino Acid Chloromethyl Ketones; Animals; Animals, Genetically Modified; Ataxin-3; Caspase Inhibitors; Caspases; Cell Line; Cysteine Proteinase Inhibitors; Disease Models, Animal; Drosophila melanogaster; Humans; Machado-Joseph Disease; Mice; Mutagenesis, Site-Directed; Nerve Tissue Proteins; Neurons; Nuclear Proteins; Repressor Proteins

We examined the effects of a caspase-1 inhibitor, N-Ac-Tyr-Val-Ala-Asp-chloromethyl ketone (Ac-YVAD-CMK), on neurogenic pulmonary edema in the endovascular perforation model of subarachnoid hemorrhage (SAH) in mice.. Ninety-seven mice were assigned to sham, SAH+vehicle, SAH+Ac-YVAD-CMK (6 or 10 mg/kg), and SAH+Z-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK, 6 mg/kg) groups. Drugs were intraperitoneally injected 1 hour post-SAH. Pulmonary edema measurements, Western blot for interleukin-1beta, interleukin-18, myeloperoxidase, matrix metalloproteinase (MMP)-2, MMP-9, cleaved caspase-3 and zona occludens-1, MMP zymography, terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining, and immunostaining were performed on the lung at 24 hours post-SAH.. Ten- but not 6-mg/kg of Ac-YVAD-CMK significantly inhibited a post-SAH increase in the activation of interleukin-1beta and caspase-3 and the number of terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling-positive pulmonary endothelial cells, preventing neurogenic pulmonary edema. Another antiapoptotic drug, Z-VAD-FMK, also reduced neurogenic pulmonary edema. SAH did not change interleukin-18, myeloperoxidase, MMP-2, MMP-9, zona occludens-1 levels, or MMP activity.. We report for the first time that Ac-YVAD-CMK prevents lung cell apoptosis and neurogenic pulmonary edema after SAH in mice.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Biomarkers; Caspase 1; Caspase Inhibitors; Cysteine Proteinase Inhibitors; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Activation; In Situ Nick-End Labeling; Injections, Intraperitoneal; Interleukin-1beta; Lung; Mice; Pulmonary Edema; Subarachnoid Hemorrhage; Treatment Outcome

Caspases and apoptosis are thought to play a role in infection-associated preterm-delivery. We have shown that in vitro treatment with pancaspase inhibitor Z-VAD-FMK protects trophoblasts from microbial antigen-induced apoptosis. Objective. To examine whether in vivo administration of Z-VAD-FMK would prevent infection-induced preterm-delivery. Methods. We injected 14.5 day-pregnant-mice with heat-killed group B streptococcus (HK-GBS). Apoptosis within placentas and membranes was assessed by TUNEL staining. Calpain expression and caspase-3 activation were assessed by immunohistochemistry. Preterm-delivery was defined as expulsion of a fetus within 48 hours after injection. Results. Intrauterine (i.u.) or intraperitoneal (i.p.) HK-GBS injection led to preterm-delivery and induced apoptosis in placentas and membranes at 14 hours. The expression of calpain, a caspase-independent inducer of apoptosis, was increased in placenta. Treatment with the specific caspase inhibitor Z-VAD-FMK (i.p.) prior to HK-GBS (i.p.) delayed but did not prevent preterm-delivery. Conclusion. Caspase-dependent apoptosis appears to play a role in the timing but not the occurrence of GBS-induced preterm delivery in the mouse.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Calpain; Caspase Inhibitors; Caspases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Extraembryonic Membranes; Female; Immunohistochemistry; In Situ Nick-End Labeling; Mice; Ovarian Follicle; Placenta; Pregnancy; Premature Birth; Streptococcal Infections; Streptococcus agalactiae

To investigate the effects of N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK), a broad caspase inhibitor, on allergic contact dermatitis (ACD).. A Balb/c mouse was killed and its back skin was peeled, put into a Franz diffusion cell, and smeared with Z-VAD-FMK. High performance liquid chromatography was used to examine the permeation rate. Dinitro-fluorobenzene (DNFB) was applied on the depilated back of mice as inducer and then on the back-side of right ear as provocative agent 6 days later so as to establish mouse ACD models. Two hours after the provocation 24 mouse models were divided into 4 equal groups to undergo the application of Z-VAD-FMK at the concentration of 0.1, 0.5, 2.5, and 5 mmol/L on the back-side of right ear twice. PBS was applied in the negative control group. Then the mice were killed with their 2 ears cut off. Microscopy was used to measure the right ear swelling degree, and differences in weight and thickness between the 2 ears. ELISA was used to detect the levels of IL-2 and INF-gamma in the ear tissues.. The transdermal permeation rates of Z-VAD-FMK at the time points 6, 12, and 24 h were 2.15%, 9.62%, and 12.85% respectively. The right ear swelling degree, and differences in weight and thickness between the 2 ears in the 2.5 mmol/L Z-VAD-FMK group were (12.5 +/- 1.4) x 10(-2) mm, (3.2 +/- 0.3) mg, and (11.8 +/- 1.3) x 10(-2) mm respectively, all significantly lower than those of the negative control group [(19.1 +/- 2.0) x 10(-2) mm, (4.3 +/- 0.4) mg, and (16.8 +/- 1.7) x 10(-2) mm, all P < 0.05]. The IL-2 and INF-gamma levels in the ear skin lesion of the 2.5 mmol/L Z-VAD-FMK group were (148 +/- 10) and (650 +/- 45) pg/ml respectively, both significantly lower than those of the negative control group [(205 +/- 18) and (1030 +/- 58) pg/ml, both P < 0.05].. Z-VAD-FMK can permeate through mouse skin and inhibit the activation and proliferation of T lymphocytes, leading to the inhibitory effect of contact allergic reaction.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Caspase Inhibitors; Cell Proliferation; Dermatitis, Allergic Contact; Disease Models, Animal; Enzyme Inhibitors; Female; Lymphocyte Activation; Mice; Mice, Inbred BALB C; T-Lymphocytes

We recently showed that acute energy failure in the rat cochlea induced by local administration of the mitochondrial toxin 3-nitropropionic acid (3-NP) causes hearing loss mainly due to degeneration of cochlear lateral-wall fibrocytes. In the present study, we analyzed the effect of the pan-caspase inhibitor z-Val-Ala-Asp(Ome)-fluoromethylketone (Z-VAD-FMK) on 3-NP-induced hearing loss in a model showing temporary threshold shifts at low frequencies and permanent threshold shifts at high frequencies. The model rats received an intraperitoneal injection of either Z-VAD-FMK or vehicle for 3 days starting 1 day prior to 3-NP treatment. One day after the administration of 3-NP, the auditory brain-stem response (ABR) threshold at 20 kHz was elevated to 70 dB in the Z-VAD-FMK group and to 85 dB in controls. The Z-VAD-FMK group completely recovered to the preoperative level within 14 days, whereas in the controls, the ABR threshold remained elevated at 50 dB even 28 days after the administration of 3-NP. Treatment with Z-VAD-FMK also improved recovery of hearing at 8 kHz but did not change recovery at 40 kHz. Histological examination demonstrated that treatment with Z-VAD-FMK inhibited progressive degeneration of the lateral-wall fibrocytes in the cochlear basal turn, as well as apoptosis of these fibrocytes. These results clearly indicate that caspase-dependent apoptosis of fibrocytes in the cochlear lateral wall plays an important role in hearing loss in the present animal model. Moreover, the results of the present study suggest that systemic administration of a caspase inhibitor may be an effective therapy for sensorineural hearing loss caused by acute energy failure such as that observed in cochlear ischemia.

Topics: Acoustic Stimulation; Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Auditory Threshold; Caspase 3; Cochlea; Disease Models, Animal; Dose-Response Relationship, Radiation; Evoked Potentials, Auditory, Brain Stem; Gene Expression Regulation; Hearing Loss, Sensorineural; Male; Neuroprotective Agents; Nitro Compounds; Propionates; Rats; Rats, Sprague-Dawley; Recovery of Function; Spiral Ganglion; Time Factors

In most retinal degenerations in humans and in animal models, photoreceptor cells die by apoptosis. Although the biochemical features are similar in all apoptotic cells, different molecular events lead the cell to death. In the present study we used a rat model of inherited retinal degeneration, the RCS rats, to investigate the involvement of the proteases, caspases and/or calpains, in photoreceptor apoptosis. In the first experiments, rats were untreated or injected intravitreally at post natal day 27 (P27) with the large broad spectrum caspase inhibitor, ZVAD, the calpain inhibitor, MuhPhe, or with the vehicle, DMSO. Retinal status was evaluated at P35 and P42 by electroretinography, morphometry and apoptotic nuclei detection. DMSO and MuhPhe had no effect on RCS retinas as evidenced by equivalent loss of function and equivalent number of apoptotic cells than in untreated group. ZVAD transiently reduced apoptotic cells and preserved photoreceptor function at P35 but not at P42. These results suggest that caspases but not calpains are involved in retinal degeneration in the RCS. In the second experiments, RCS rats were injected twice at P27 and P35 with ZVAD or DMSO. Although ZVAD-treated retinas were preserved at P35 compared to the DMSO controls, the second injection of ZVAD did not extend the preserving effect to P42. Moreover, a single injection of ZVAD at P35 had no preserving effect at P42. All these data taken together suggest that caspases do not play a pivotal role after P35. In a fourth set of experiments, we used specific caspase inhibitors to elucidate which caspase was activated. The caspase-1/4 inhibitor (YVAD) or the caspase-3/7 inhibitor (DEVD) were injected intravitreally at P27 and retinal status was evaluated at P35 and P42. Electroretinograms and apoptotic nuclei detection demonstrated that YVAD and DEVD preserved photoreceptors at P35 but not at P42. These results suggest that both caspase-1/4 and caspase-3/7 play a major role in the apoptotic pathway between P27 and P35 in retinal degeneration of RCS rats. In this study, we show that 1/ the photoreceptor apoptotic process in the RCS rat involves caspases but not calpains, and 2/ the retinal degeneration seems to be composed of different phases involving different molecular players. Indeed, we have demonstrated that caspases are playing a major role at P35, but not at P42.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Calpain; Caspase Inhibitors; Caspases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Drug Administration Schedule; Electroretinography; Optic Nerve; Photoreceptor Cells, Vertebrate; Rats; Rats, Mutant Strains; Retinal Degeneration; Time Factors

Acute liver failure after massive hepatectomy is caused by both necrosis and apoptosis in the remnant liver. We investigate the protective effect of the caspase inhibitor on apoptosis after massive hepatectomy in rats.. Benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (ZVAD-fmk) is a general inhibitor of the caspase. Male Wister rats weighing 200-300 g were divided into three groups: 90Hx group undergoing 90% hepatectomy, 95Hx group undergoing 95% hepatectomy, 95Hx + ZVAD group undergoing 95% hepatectomy and administration of ZVAD-fmk. The 7-day survival rate was studied, and the rats were sacrificed at the 1, 2, 3, 5, and 7th day after hepatectomy. The remnant liver tissues were stained with hematoxylin-eosin, and with proliferating cell nuclear antigen (PCNA) for evaluation of liver regeneration, and with TdT-mediated dUTP-biotin nick end labeling (TUNEL) and in situ oligo ligation method (ISOL) for evaluation of apoptosis.. The 7-day survival rates were 100%, 0%, and 30%, in the 90Hx, 95Hx, and 95Hx + ZVAD groups, respectively. There was no significant difference in PCNA labeling index (LI) between the 95Hx and 95Hx + ZVAD groups. TUNEL and ISOL LI of 95Hx + ZVAD group were significantly lower than those of 95Hx group. Fatal liver failure after massive hepatectomy was characterized by more apoptosis and less mitosis of hepatocytes. ZVAD-fmk could significantly attenuate apoptosis of hepatocytes in the remnant liver and improve the survival rate after 95% hepatectomy in rats.. Caspase inhibitors such as ZVAD-fmk may provide a new adjuvant therapy to treat liver failure after massive hepatectomy.

Topics: Alanine Transaminase; Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Caspase Inhibitors; Caspases; Cell Proliferation; Cysteine Proteinase Inhibitors; Disease Models, Animal; Hepatectomy; In Situ Nick-End Labeling; Liver; Liver Failure; Liver Regeneration; Male; Proliferating Cell Nuclear Antigen; Rats; Rats, Wistar; Time Factors

Inflammation in the subarachnoid space and apoptosis of arterial endothelial cells have been implicated in the development of delayed cerebral vasospasm after subarachnoid hemorrhage (SAH). The authors investigated mechanisms of possible antivasospastic effects of N-benzyl-oxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK), a caspase inhibitor that can inhibit both inflammatory and apoptotic systems, in animal models of SAH.. Rabbits were assigned to three groups of eight animals each and were subjected to SAH by injection of blood into the cisterna magna. The experiments were performed in the following groups: SA only, SAH + vehicle, and SAH + Z-VAD-FMK. The Z-VAD-FMK (1 mg) or vehicle (5% dimethyl sulfoxide) was intrathecally administered before SAH induction. Diameters of the basilar artery (BA) were measured on angiograms obtained before and 2 days after SAH. The BA diameter on Day 2 was expressed as a percentage of that before SAH. Interleukin (IL)-1 in the cerebrospinal fluid (CSF) was examined using Western blotting, and brains were immunohistochemically examined for caspase-1 and IL-1beta. In a separate experiment, 20 rats were subjected to SAH and their brains were immunohistochemically assessed for caspase-1, IL-1beta, and macrophages. RESULTS. In rabbits, Z-VAD-FMK significantly attenuated cerebral vasospasm (the BA diameter on Day 2 in SAH-only, SAH + vehicle, and SAH + Z-VAD-FMK groups was 66.6 +/- 3.2%, 66.3 +/- 3.7%, and 82.6 +/- 4.9% of baseline, respectively), and suppressed IL-1beta release into the CSF and also suppressed immunoreactivities of caspase-1 and IL-1P in macrophages infiltrating into the subarachnoid space. Immunoreactivities for caspase-1 and IL-1P were observed in immunohistochemically proven infiltrating macrophages in rats.. These results indicate that caspase activation may be involved in the development of SAH-induced vasospasm through inflammatory reaction.

Topics: Amino Acid Chloromethyl Ketones; Animals; Basilar Artery; Blotting, Western; Brain; Caspase 1; Caspase Inhibitors; Cerebral Angiography; Disease Models, Animal; Fluorescent Antibody Technique; Interleukin-1beta; Macrophages; Male; Neuroprotective Agents; Rabbits; Subarachnoid Hemorrhage

Two apoptosis signaling pathways, which are used by different cell types, are identified. The activation of caspases is critical for the apoptosis process. The aim of this study was to investigate the effects of the caspase-9 inhibitor Ac-LEHD-CHO on tumor necrosis factor receptor (TNFR)- and Fas-mediated hepatocyte apoptosis in vivo, in order to evaluate the similarities and distinctions between TNFR- and Fas-mediated signaling pathways.. BALB/c mice were intravenously injected with d-galactosamine (GalN, 20 mg/mouse)/tumor necrosis factor-alpha (TNF-alpha, 0.5 microg/mouse), or alphaFas (10 microg/mouse) 30 min after treatment with the caspase-9 inhibitor Ac-LEHD-CHO or pan-caspase inhibitor Z-VAD-fmk. Liver injury was assessed biochemically and histologically. Cytochrome c release and processing of procaspases in the liver were analyzed by Western blotting. Activities of caspases were measured using a fluorogenic peptide substrate.. Pretreatment with Z-VAD-fmk prevented liver injury and hepatocyte apoptosis induced by either GalN/TNF-alpha or alphaFas. On the other hand, pretreatment with Ac-LEHD-CHO prevented GalN/TNF-alpha-induced hepatotoxicity and hepatocyte apoptosis but not alphaFas-induced liver injury and apoptosis. Both inhibitors reduced the activities of caspase-9 and -3 in the livers of mice administered by GalN/TNF-alpha. However, unlike Z-VAD-fmk, Ac-LEHD-CHO did not inhibit caspase-3 activation in alphaFas-treated mice, although this inhibitor attenuated caspase-9.. Fas may rely on both caspase-8 activation (extrinsic pathway) and mitochondria (intrinsic pathway) to activate caspase-3. If the mitochondria-dependent pathway is blocked, the other pathway can compensate. In contrast, TNFR may mediate hepatocellular apoptosis mainly through the mitochondria-mediated caspase-9 activation pathway alone.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Blotting, Western; Caspase 9; Caspases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Enzyme Activation; fas Receptor; Galactosamine; Hepatocytes; In Situ Nick-End Labeling; Male; Mice; Mice, Inbred BALB C; Random Allocation; Receptors, Tumor Necrosis Factor; Signal Transduction

Recent studies have demonstrated that articular cartilage injury leads to chondrocyte death through a mechanism termed "apoptosis", or programmed cell death (PCD). Inhibitors of caspases, key enzymatic mediators of apoptosis, have been shown to block chondrocyte PCD. We hypothesized that short-term intra-articular administration of a potent caspase inhibitor would decrease chondrocyte PCD and subsequent cartilage degeneration following experimental osteochondral injury in rabbits.. Adult New Zealand white rabbits were subjected to osteochondral injuries of their femoral condyles. Knees in the treatment group received daily intra-articular injections of the broad-spectrum caspase inhibitor Z-VAD-fmk for 7 days, while the control group received injections of vehicle alone. Seven days postinjury, one group of rabbits was sacrificed to assess levels of chondrocyte PCD. A second group was sacrificed 42 days postinjury for histological evaluation to measure cartilage degeneration and cartilage repair.. Seven days postinjury, there was a 45% reduction in chondrocyte PCD in the caspase inhibitor treated knees as compared to controls (P=0.01). Forty-two days postinjury, treated knees were found to have 17.9% greater chondrocyte survival (P<0.01) and 7.6% greater articular cartilage thickness (P=0.01).. Intra-articular administration of the caspase inhibitor Z-VAD-fmk effectively blocks chondrocyte PCD following experimental osteochondral injury in this model. Inhibition of chondrocyte PCD rescues chondrocytes that would otherwise die, limiting subsequent cartilage loss. To our knowledge, this study is the first to demonstrate that short-term inhibition of chondrocyte PCD leads to long-term preservation of cartilage in vivo.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Cartilage, Articular; Caspase Inhibitors; Chondrocytes; Cysteine Proteinase Inhibitors; Disease Models, Animal; Femur; Injections, Intra-Articular; Rabbits

Traumatic brain injury is associated with acute subdural hematoma (ASDH) that worsens outcome. Although early removal of blood can reduce mortality, patients still die or remain disabled after surgery and additional treatments are needed. The blood mass and extravasated blood induce pathomechanisms such as high intracranial pressure (ICP), ischemia, apoptosis and inflammation which lead to acute as well as delayed cell death. Only little is known about the basis of delayed cell death in this type of injury. Thus, the purpose of the study was to investigate to which extent caspase-dependent intracellular processes are involved in the lesion development after ASDH in rats. A volume of 300microL blood was infused into the subdural space under monitoring of ICP and tissue oxygen concentration. To asses delayed cell death mechanisms, DNA fragmentation was measured 1, 2, 4 and 7 days after ASDH by TUNEL staining, and the effect of the pan-caspase inhibitor zVADfmk on lesion volume was assessed 7 days post-ASDH. A peak of TUNEL-positive cells was found in the injured cortex at day 2 after blood infusion (53.4+/-11.6 cells/mm(2)). zVADfmk (160ng), applied by intracerebroventricular injection before ASDH, reduced lesion volume significantly by more than 50% (vehicle: 23.79+/-7.62mm(3); zVADfmk: 9.06+/-4.08). The data show for the first time that apoptotic processes are evident following ASDH and that caspase-dependent mechanisms play a crucial role in the lesion development caused by the blood effect on brain tissue.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Blood; Brain Infarction; Brain Injuries; Brain Ischemia; Caspases; Disease Models, Animal; Enzyme Inhibitors; Hematoma, Subdural, Acute; In Situ Nick-End Labeling; Intracranial Hypertension; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Signal Transduction; Treatment Outcome

In the present study we assessed the neuroprotective effects of the pan-caspase inhibitor z-VAD.fmk [N-benzyloxycarbony-valine-alanine-aspartate-(OMe)-fluoromethylketone], and the caspase-3 inhibitor Ac-DEVD.CHO (acetyl-aspartate-chloromethylketone) in the double-lesion rat model of striatonigral degeneration (SND), the core pathology underlying levodopa-unresponsive parkinsonism associated with multiple system atrophy (MSA). Male Wistar rats were divided into three groups, receiving either Ac-DEVD.CHO, z-VAD.fmk or normal saline before lesion surgery, comprising a sequential unilateral quinolinic acid (QA) lesion of the striatum followed by a 6-hydroxydopamine (6-OHDA) lesion of the ipsilateral medial forebrain bundle. At 2 weeks post lesion, all rats underwent testing of spontaneous nocturnal locomotor behavior in an automated Photobeam Activity System (FlexField). Immunohistochemistry was performed with tyrosine hydroxylase, dopamine and cyclic adenosine 3',5'-monophosphate-regulated phosphoprotein and glial fibrillary acidic protein antibodies. Morphometry was performed using computerized image analysis. Behavioral and morphological analysis failed to show striatal or nigral protection in caspase inhibitor-treated animals. Our findings suggest that anti-apoptotic strategies are unrewarding in the SND rat model and, therefore, alternative neuroprotective interventions such as anti-glutamatergic agents or inhibitors of microglial activation should be explored instead.

Topics: Amino Acid Chloromethyl Ketones; Analysis of Variance; Animals; Basal Ganglia; Behavior, Animal; Caspase Inhibitors; Cell Count; Cell Size; Disease Models, Animal; Dopamine and cAMP-Regulated Phosphoprotein 32; Functional Laterality; Immunohistochemistry; Male; Motor Activity; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Neuroprotective Agents; Oligopeptides; Oxidopamine; Phosphoproteins; Quinolinic Acid; Rats; Rats, Wistar; Tyrosine 3-Monooxygenase

Meconium aspiration syndrome (MAS) is common among newborn children but its mechanism is unclear. The syndrome is known to produce a strong inflammatory reaction in the lungs resulting in massive cell death. In this work we studied lung cell death by apoptosis after meconium aspiration in forty two-week-old rabbit pups. Analyzing lung samples by ISEL-DNA end labeling demonstrated the specific spread of apoptotic bodies throughout the lungs. These bodies were shrunken and smaller in size compared to normal cells and many of them were lacking cell membranes. About 70% of all apoptotic bodies were found among the airway epithelium cell eight hours after meconium instillation. In comparison, among lung alveolar cells, only about 20% cells were apoptotic in the same animals. In meconium-treated lungs and A549 cells, a significant increase of angiotensinogen mRNA and Caspase-3 expression were observed. The pretreatment of cells with Caspase-3 inhibitor ZVAD-fmk significantly inhibited meconium-induced lung cell death by apoptosis. These findings demonstrate the apoptotic process in meconium-instilled lungs or A549 cells in culture. Our results show lung airway epithelial and A549 cell apoptosis after meconium instillation. We suggest that studies of lung airway epithelial cell death are essential to understanding the pathophysiology of MAS and may present a key point in future therapeutic applications.

Topics: Amino Acid Chloromethyl Ketones; Angiotensinogen; Animals; Apoptosis; Bronchoalveolar Lavage Fluid; Caspase 3; Caspase Inhibitors; Caspases; Cell Line, Tumor; Cysteine Proteinase Inhibitors; Disease Models, Animal; Epithelial Cells; Humans; Infant, Newborn; Lung; Meconium Aspiration Syndrome; Rabbits; Reverse Transcriptase Polymerase Chain Reaction

Amyotrophic lateral sclerosis (ALS) is an adult-onset degenerative disorder characterised by the death of motor neurons in the cortex, brainstem, and spinal cord; resulting in progressive muscle weakness, atrophy, and death from respiratory paralysis, usually within 3-5 years of symptom onset. Approximately 10% of ALS cases are familial (FALS). Mutations in superoxide dismutase-1 (SOD1) cause approximately 20% of FALS cases and there is overwhelming evidence that a toxic gain of function is the cause of the disease. We have previously shown that FALS-associated SOD1 disease mutants enhanced neuronal death in response to a wide range of stimuli tested whereas wt-SOD1 protected against all insults. We demonstrate for the first time that over-expression of either heat shock protein Hsp27 or Hsp70 has a protective effect against SOD1 disease associated mutant-induced cell death. However, over-expression of Hsp27 and Hsp70 together has a greater potent anti-apoptotic effect, than when expressed singly, against the damaging effects of mutant SOD1. Our results indicate that FALS-associated SOD1 disease mutants possess enhanced death-inducing properties and lead to increased apoptosis which can be prevented by either the use of specific caspase inhibitors or Hsp27 and/or Hsp70 over-expression. This potent protective effect of Hsp27 and Hsp70 against the FALS-associated SOD1 disease mutants may be of potential therapeutic importance.

Topics: Amino Acid Chloromethyl Ketones; Amyotrophic Lateral Sclerosis; Analysis of Variance; Animals; Animals, Newborn; Blotting, Western; Cell Death; Cells, Cultured; Cricetinae; Culture Media, Serum-Free; Disease Models, Animal; Drug Combinations; Drug Interactions; Enzyme Inhibitors; Ganglia, Spinal; Genetic Vectors; Green Fluorescent Proteins; Heat-Shock Proteins; HIV-1; HSP27 Heat-Shock Proteins; HSP70 Heat-Shock Proteins; In Situ Nick-End Labeling; Mutagenesis; Mutation; Neoplasm Proteins; Neurons; Neuroprotective Agents; Rats; Staurosporine; Superoxide Dismutase; Superoxide Dismutase-1; Time Factors; Transfection

We investigated the antitumoral efficacy, endocrine consequences, and molecular mechanisms underlying cell death induced by the Hecate-chorionic gonadotropin (CG)beta conjugate, a fusion protein of a 23-amino acid lytic peptide Hecate with a 15-amino acid (81-95) fragment of the human CGbeta chain. Transgenic (TG) mice expressing the inhibin alpha-subunit promoter (inhalpha)/Simian Virus 40 T-antigen (Tag) transgene, developing luteinizing hormone (LH) receptor (R) expressing Leydig and granulosa cell tumors, and wild-type control littermates were treated either with vehicle, Hecate, or Hecate-CGbeta conjugate for 3 weeks. Hecate-CGbeta conjugate treatment reduced the testicular and ovarian tumor burden (P < .05), whereas a concomitant increase (testis; P < .05) or no change (ovary) in tumor volumes occured with Hectate treatment. A drop in serum progesterone, produced by the tumors, and an increase in LH levels occured in Hecate-CGbeta treated mice, in comparison with vehicle and Hecate groups, providing further support for the positive treatment response. Hecate-CGbeta conjugate induced a rapid and cell-specific membrane permeabilization of LHR-expressing cells in vitro, suggesting a necrotic mode of cell death without activation of apoptosis. These results prove the principle that the Hecate-CGbeta conjugate provides a novel specific lead into gonadal somatic cell cancer therapy by targeted destruction of LHR-expressing tumor cells.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Blotting, Northern; Caspase 3; Caspases; Cell Death; Cell Line, Tumor; Cell Separation; Chorionic Gonadotropin, beta Subunit, Human; Disease Models, Animal; Enzyme Activation; Female; Flow Cytometry; Granulosa Cell Tumor; Humans; Leydig Cell Tumor; Male; Melitten; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Fluorescence; Necrosis; Ovarian Neoplasms; Progesterone; Promoter Regions, Genetic; Protein Structure, Tertiary; Receptors, LH; Recombinant Fusion Proteins; Testicular Neoplasms; Time Factors

Acute renal failure (ARF) is a frequent and serious complication of endotoxemia caused by lipopolysaccharide (LPS) and contributes significantly to mortality. The present studies were undertaken to examine the roles of nitric oxide (NO) and caspase activation on renal peritubular blood flow and apoptosis in a murine model of LPS-induced ARF. Male C57BL/6 mice treated with LPS (Escherichia coli) at a dose of 10 mg/kg developed ARF at 18 h. Renal failure was associated with a significant decrease in peritubular capillary perfusion. Vessels with no flow increased from 7 +/- 3% in the saline group to 30 +/- 4% in the LPS group (P < 0.01). Both the inducible NO synthase inhibitor L-N(6)-1-iminoethyl-lysine (L-NIL) and the nonselective caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp fluoromethylketone (Z-VAD) prevented renal failure and reversed perfusion deficits. Renal failure was also associated with an increase in renal caspase-3 activity and an increase in renal apoptosis. Both L-NIL and Z-VAD prevented these changes. LPS caused an increase in NO production that was blocked by L-NIL but not by Z-VAD. Taken together, these data suggest NO-mediated activation of renal caspases and the resulting disruption in peritubular blood flow are an important mechanism of LPS-induced ARF.

Topics: Acute Kidney Injury; Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Caspase Inhibitors; Caspases; Disease Models, Animal; Enzyme Activation; Interferon-gamma; Kidney Cortex; Lipopolysaccharides; Lysine; Male; Mice; Mice, Inbred C57BL; Nitric Oxide; Nitric Oxide Synthase Type II; Renal Circulation; Tumor Necrosis Factor-alpha

Cell death, especially apoptosis, occurred in brain tissues after subarachnoid hemorrhage (SAH). We examined the relationships between apoptosis and the disruption of blood-brain barrier (BBB), brain edema, and mortality in an established endovascular perforation model in male Sprague-Dawley rats.. A pan-caspase inhibitor (z-VAD-FMK) was administered intraperitoneally at 1 hour before and 6 hours after SAH. Expression of caspase-3 and positive TUNEL was examined as markers for apoptosis.. Apoptosis occurred mostly in cerebral endothelial cells, partially in neurons in the hippocampus, and to a lesser degree in the cerebral cortex. Accordingly, increased BBB permeability and brain water content were observed, accompanied by neurological deficit and a high mortality at 24 hours after SAH. z-VAD-FMK suppressed TUNEL and caspase-3 staining in endothelial cells, decreased caspase-3 activation, reduced BBB permeability, relieved vasospasm, abolished brain edema, and improved neurological outcome.. The major effect of z-VAD-FMK on early brain injury after SAH was probably neurovascular protection of cerebral endothelial cells, which results in less damage on BBB.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Blood-Brain Barrier; Brain Edema; Caspase 3; Caspases; Disease Models, Animal; Male; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Subarachnoid Hemorrhage

Malignant mesothelioma (MM) is a cancer with uniformly poor responses to current therapeutic regimens. This study evaluates whether taurolidine, a novel antineoplastic agent, is effective against human MM cell lines and a murine model of human MM.. Cell growth inhibition and viability assays were performed on REN, LRK, and H28 cell lines after 24-72-h exposure to 0-200 microm taurolidine. Cell cycle analysis with annexin-V binding, terminal deoxynucleotidyl transferase-mediated nick end labeling assay, electron microscopy, and response to the general caspase inhibitor z-VAD-fmk were performed on MM cell lines after 24-72-h exposure to 50-150 microm taurolidine. Athymic mice were given i.p. injections of 20 x 10(6) REN cells, followed by i.p. taurolidine (17.5 or 20 mg), 3 days/week for up to 3 weeks. Tumors were assessed at day 30. All statistical tests were two-sided.. A 72-h exposure of MM cells to taurolidine showed IC50 of 28-42.7 microm and 50% viability at 49.8-135 microm. Annexin V assay for apoptosis revealed significant increases in annexin binding after 24-72-h exposure to 50-150 microm taurolidine (P <0.05), which was significantly inhibited by z-VAD (P <0.05). MM cells exposed to 50-150 microm taurolidine for 24-72 h showed terminal deoxynucleotidyl transferase-mediated nick end labeling staining consistent with apoptosis, as well as structural evidence of apoptosis via electron microscopy. In vivo, there were significant tumor reductions (62 to >99% reduction) for all dosage regimens compared with untreated controls (P <0.001). In addition, all control animals exhibited ascites and diaphragmatic tumors while treated animals did not.. Taurolidine has significant antineoplastic activity against MM in vitro and in vivo, in part, due to tumor cell apoptosis. These findings warrant further study for potential clinical usefulness.

Topics: Amino Acid Chloromethyl Ketones; Animals; Annexin A5; Antineoplastic Agents; Apoptosis; Body Weight; Caspases; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Disease Models, Animal; Enzyme Inhibitors; Humans; In Situ Nick-End Labeling; Lung Neoplasms; Male; Mesothelioma; Mice; Mice, Nude; Microscopy, Electron; Phosphatidylserines; Taurine; Thiadiazines; Time Factors

Asthma is characterized by acute and chronic airway inflammation, and the severity of the airway hyperreactivity correlates with the degree of inflammation. Many of the features of lung inflammation observed in human asthma are reproduced in OVA-sensitized/challenged mice. T lymphocytes, particularly Th2 cells, are critically involved in the genesis of the allergic response to inhaled Ag. In addition to antiapoptotic effects, broad-spectrum caspase inhibitors inhibit T cell activation in vitro. We investigated the effect of the broad-spectrum caspase inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), on airway inflammation in OVA-sensitized/challenged mice. OVA-sensitized mice treated with z-VAD-fmk immediately before allergen challenge showed marked reduction in inflammatory cell infiltration in the airways and pulmonary blood vessels, mucus production, and Th2 cytokine production. We hypothesized that the caspase inhibitor prevented T cell activation, resulting in the reduction of cytokine production and eosinophil infiltration. Treatment with z-VAD-fmk in vivo prevented subsequent T cell activation ex vivo. We propose that caspase inhibitors may offer a novel therapeutic approach to T cell-dependent inflammatory airway diseases.

Topics: Aerosols; Allergens; Amino Acid Chloromethyl Ketones; Animals; Asthma; Bronchial Hyperreactivity; Bronchoalveolar Lavage Fluid; Caspase Inhibitors; Cell Movement; Cysteine Proteinase Inhibitors; Disease Models, Animal; Inflammation; Interleukin-4; Interleukin-5; Intubation, Intratracheal; Leukocytes; Lung; Lymphocyte Activation; Methacholine Chloride; Mice; Mice, Inbred BALB C; Ovalbumin; T-Lymphocytes

We examined whether the well-known neurotoxins 6-hydroxydopamine (6-OHDA) and 1-methyl-4-phenylpyridinium ion (MPP(+)) recruit distinct cell death mechanisms using primary cultured neurons derived from day 16 embryonic rat cortices. Electron microscopy revealed that cell death induced by both 6-OHDA and MPP(+) was typified by a condensation of chromatin while prominent mitochondrial swelling was observed only in those cells treated with MPP(+). Co-treatment of cells with a pan-caspase inhibitor, Z-VAD-fmk, attenuated 6-OHDA-induced chromatin condensation and neuronal death. Co-treatment with such antioxidants as N-acetylcysteine or Mn-TBAP also suppressed 6-OHDA-induced cell death. None of these treatments attenuated MPP(+)-induced cell death although caspase inhibition abolished MPP(+)-induced chromatin condensation. Interestingly, in these paradigms of cell death, the N-terminus of tau was specifically cleaved and the levels of phosphorylated tau were markedly decreased following 6-OHDA treatment. By contrast, the C-terminus of tau was cleaved in MPP(+)-induced cell death while the levels of phosphorylated tau remained largely unaltered. Taken together, our results indicate that distinct cellular mechanisms appear to underlie neurotoxin-induced cortical neuronal cell death.

Topics: 1-Methyl-4-phenylpyridinium; Acetylcysteine; Amino Acid Chloromethyl Ketones; Animals; Animals, Newborn; Apoptosis; Cell Culture Techniques; Cerebral Cortex; Cysteine Proteinase Inhibitors; Disease Models, Animal; Drug Interactions; Free Radical Scavengers; Microscopy, Electron; Mitochondria; Neurons; Oxidopamine; Peptide Fragments; Phosphorylation; Rats; Rats, Sprague-Dawley; Superoxide Dismutase; tau Proteins; Time Factors

The role of alveolar macrophages (AM) in host defense against pulmonary infection has been difficult to establish using in vivo models. This may reflect a reliance on models of fulminant infection. To establish a unique model of resolving infection, with which to address the function of AM, C57BL/6 mice received low-dose intratracheal administration of pneumococci. Administration of low doses of pneumococci produced a resolving model of pulmonary infection characterized by clearance of bacteria without features of pneumonia. AM depletion in this model significantly increased bacterial outgrowth in the lung. Interestingly, a significant increase in the number of apoptotic AM was noted with the low-dose infection as compared with mock infection. Caspase inhibition in this model decreased AM apoptosis and increased the number of bacteremic mice, indicating a novel role for caspase activation in pulmonary innate defense against pneumococci. These results suggest that AM play a key role in clearance of bacteria from the lung during subclinical infection and that induction of AM apoptosis contributes to the microbiologic host defense against pneumococci.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Bacteremia; Caspase Inhibitors; Cell Count; Cysteine Proteinase Inhibitors; Disease Models, Animal; Dose-Response Relationship, Immunologic; Female; Immunity, Innate; Injections, Intraperitoneal; Intubation, Intratracheal; Macrophages, Alveolar; Mice; Mice, Inbred C57BL; Pneumonia, Pneumococcal; Streptococcus pneumoniae; Up-Regulation

Ischemia-reperfusion (I/R) leads to organ injury and organ dysfunction in a variety of clinical disorders. Preclinical investigations examining leukocyte adhesion molecules in I/R provided overwhelming evidence that blocking the function of leukocyte adhesion molecules would be highly effective in improving outcome in clinically relevant diseases. Unfortunately, all 9 of the recently completed phase 2 and 3 clinical trials examining antiadhesion therapy have failed. In this report, we show that a modest increase in ischemic time results in conversion from a CD18-dependent to a CD18-independent injury. This fundamental change in the mechanism of injury can be reduced by inhibition of caspases leading to blockade of apoptosis. Muscle injury resulting from aortic clamping was measured by release of creatine kinase. I/R injury following ischemia of 60 minutes or less and 3 hours of reperfusion was significantly reduced by pretreatment with anti-CD18 monoclonal antibody. However, 90 minutes of ischemia resulted in a marked increase in injury that was not reduced by CD18 blockade. Importantly, the injury resulting from 90 or 120 minutes of ischemia was reduced by the pancaspase inhibitor z-VAD. We propose that the length of ischemia can result in a fundamental change in the mechanism of injury and that all preclinical investigations of I/R must be evaluated with increasing ischemia if they are to model the clinical disease. The result showing CD18-independent I/R injury is not unique; likewise, protection by caspase inhibitors is not unique. However, we show for the first time that caspase inhibitors are effective when CD18 blockade is not.

Topics: Amino Acid Chloromethyl Ketones; Animals; Antibodies, Monoclonal; Apoptosis; Caspase Inhibitors; CD18 Antigens; Cell Adhesion; Clinical Trials as Topic; Disease Models, Animal; Leukocytes; Mice; Mice, Inbred BALB C; Muscle, Skeletal; Reperfusion Injury; Time Factors

A caspase-3-activated DNase produces internucleosomal DNA cleavage (DNA laddering). We determined whether caspase-3 is activated by lithium-pilocarpine-induced status epilepticus in six brain regions with necrosis-induced DNA laddering. The thymuses of adult rats given methamphetamine or normal saline were used as controls for apoptosis. Some 6-8 h after methamphetamine treatment, thymocytes showed apoptosis by electron-microscopic examination, positive terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL), DNA laddering, cleavage of caspase-3 into its active p17 subunit, active caspase-3 immunoreactivity, and a 25-fold increase in caspase-3-like activity. Six hours after SE, necrotic neurons by electron-microscopic examination in hippocampus, amygdala and piriform, entorhinal and frontal cortices showed no TUNEL and no DNA laddering. Twenty-four hours after seizures, most necrotic neurons were negative for TUNEL, some were positive, but all regions showed DNA laddering. However, 6 and 24 h after seizures, active caspase-3 immunoreactivity was negative, caspase-3-like activity did not increase, and western blot analysis failed to show the p17 subunit. In addition, 24 h after seizures,microdialytic perfusion of carbobenzoxy-valyl-alanyl-aspartyl (O-methylester) fluoromethylketone was not neuroprotective. Thus, caspase-3 is not activated in brain regions with seizure-induced neuronal necrosis with DNA laddering. Either caspase-activated DNase is activated by another enzyme, or a caspase-independent DNase is responsible for the DNA cleavage.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Brain; Caspase 3; Caspases; Disease Models, Animal; DNA; DNA Fragmentation; Enzyme Activation; Enzyme Inhibitors; In Situ Nick-End Labeling; Male; Methamphetamine; Microdialysis; Necrosis; Neurons; Pilocarpine; Rats; Rats, Wistar; Seizures; Status Epilepticus; Thymus Gland; Time Factors

Trauma triggers diffuse apoptotic neurodegeneration in the developing rat brain. To explore the pathogenesis of this phenomenon we investigated the involvement of three possible mechanisms: death receptor activation, activation of the intrinsic apoptotic pathway by cytochrome c release into the cytoplasm, and changes in trophic support provided by endogenous neurotrophins. We detected a decrease in the expression of bcl-2 and bcl-x(L), two antiapoptotic proteins that decrease mitochondrial membrane permeability, an increase in cytochrome c immunoreactivity in the cytosolic fraction, and an activation of caspase-9 in brain regions which show apoptotic neurodegeneration following percussion brain trauma in 7-day-old rats. Increase in the expression of the death receptor Fas was revealed by RT-PCR analysis, Western blotting, and immunohistochemistry, as was activation of caspase-8 in cortex and thalamus. Apoptotic neurodegeneration was accompanied by an increase in the expression of BDNF and NT-3 in vulnerable brain regions. The pancaspase inhibitor z-VAD.FMK ameliorated apoptotic neurodegeneration with a therapeutic time window of up to 8 h after trauma. These findings suggest involvement of intrinsic and extrinsic apoptotic pathways in neurodegeneration following trauma to the developing rat brain. Upregulation of neurotrophin expression may represent an endogenous mechanism that limits this apoptotic process.

Topics: Amino Acid Chloromethyl Ketones; Animals; Animals, Newborn; Apoptosis; bcl-X Protein; Brain; Brain Injuries; Brain-Derived Neurotrophic Factor; Caspase 9; Caspases; Cyclin D1; Cytochrome c Group; Disease Models, Animal; DNA Fragmentation; Dose-Response Relationship, Drug; Drug Administration Schedule; Enzyme Inhibitors; fas Receptor; Immunohistochemistry; Nerve Degeneration; Neurons; Neurotrophin 3; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Wistar; RNA, Messenger; Signal Transduction

Infection of mice with Plasmodium Berghei Anka (PbA) leads to a thrombocytopenia, due to a reduced platelet life span, eventually associated with a syndrome of severe or cerebral malaria (CM). Thrombocytopenia was associated with an increase in the number of microparticles (mcp) in plasma. More than >60% of these mcp were of platelet origin, as seen by staining with an anti-platelet antibody. The thrombocytopenia and the amount of mcp were decreased in mice treated with anti CD40L mAb, suggesting that CD40L is the main effector of the thrombocytopenia. Caspase-1, -3, -6, -8, -9 were activated in platelets from infected mice, as seen by the binding of labeled probes or the amount of pro-caspase-3. Treatment of infected mice with the caspases inhibitor ZVAD-fmk decreased the number of mcp and the thrombocytopenia, showing that platelet caspases are responsible for platelet fragmentation. In addition, the caspase inhibitor also caused a decrease in the mortality associated with CM, indicating a critical role of caspases in the expression of CM.

Topics: Amino Acid Chloromethyl Ketones; Animals; Blood Platelets; Blotting, Western; Caspase 1; Caspase 3; Caspase 6; Caspase 8; Caspase 9; Caspases; CD40 Ligand; Cricetinae; Cysteine Proteinase Inhibitors; Disease Models, Animal; Enzyme Activation; Flow Cytometry; Malaria; Megakaryocytes; Mice; Mice, Inbred C57BL; Microscopy, Fluorescence; Peptides; Plasmodium berghei; Protein Binding; Thrombocytopenia; Time Factors; Tumor Necrosis Factor-alpha

Colloidal bismuth subcitrate (CBS), a drug for treatment of peptic ulcers, has been reported in the literature to be nephrotoxic in humans when taken in high overdoses. To investigate the mechanism of bismuth nephropathy, we developed an animal model by feeding rats single doses of CBS containing 3.0 mmol Bi/kg body weight. Terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling assay, immunostaining for active caspase-3, and electron microscopy showed that proximal tubular epithelial cells die by necrosis and not by apoptosis within 3 h after CBS administration. Exposure of the renal epithelial cell lines NRK-52E and LLC-PK1 to Bi(3+) in citrate buffer served as an in vitro model of bismuth nephropathy. NRK-52E cells exposed to 100 microM Bi(3+) or more died by necrosis, as was demonstrated by nuclear staining with Hoechst 33258 and flow cytometry using Alexa(488)-labeled Annexin-V and the vital nuclear dye TOPRO-3. Bismuth-induced cell death of NRK-52E cells was not prevented by the caspase-3 inhibitor z-VAD-fmk, whereas this inhibitor did prevent cisplatinum-induced apoptosis. Mitochondrial dysfunction and induction of free radicals were shown not to be involved in bismuth nephrotoxicity. The early time point of damage induction in vitro as well as in vivo and the early displacement of N-cadherin, as found in previous studies, suggest that bismuth induces cell death by destabilizing the cell membrane. In conclusion, we showed that high overdose of bismuth induced cell death by necrosis in vivo as well as in vitro, possibly by destabilization of the cell membrane.

Topics: Amino Acid Chloromethyl Ketones; Animals; Anti-Ulcer Agents; Apoptosis; Caspase 3; Caspase Inhibitors; Caspases; Cell Death; Cell Membrane; Cysteine Proteinase Inhibitors; Disease Models, Animal; Female; Flow Cytometry; In Situ Nick-End Labeling; Kidney Diseases; Kidney Tubules, Proximal; LLC-PK1 Cells; Microscopy, Electron; Mitochondria; Organometallic Compounds; Rats; Rats, Wistar

Marrow stromal cells (MSCs) transplantation into brain has been employed to treat experimental ischemia. However, MSCs undergo apoptosis and few survive in the ischemic brain. We test the hypotheses that coadministration of bone marrow cells (BMCs) with a cell-permeable inhibitor of caspases, Z-Val-Ala-DL-Asp-fluoromethylketone (Z-VAD), into the ischemic boundary zone (IBZ) of brain promotes BMCs survival and improve outcome. Experimental groups consist of: 24 h after MCAo, either phosphate-buffered saline (PBS, n=4), dead BMC (n=4), fresh BMC (n=10), Z-VAD only (n=4), or BMC with Z-VAD (n=6) were intracerebrally injected. BMCs were harvested from donor adult rats labeled with bromodeoxyuridine (BrdU). Rats were subjected to an adhesive-removal somatosensory and motor-rotarod functional tests before MCAo and at 1 and 7 days after MCAo. Rats treated with a combination of Z-VAD and BMCs exhibited significant improvement in the adhesive-removal test at 7 days compared with the control group (combined MCAo+PBS and MCAo+dead BMC) (p<0.01), and the numbers of BrdU-BMC increased (p<0.05) and apoptotic cells decreased (p<0.05) compared with BMC alone transplantation. Our data suggest that intracerebral coadministration of BMC with Z-VAD enhances the survival of grafted BMC and improves neurological functional recovery after MCAo.

Topics: Amino Acid Chloromethyl Ketones; Animals; Behavior, Animal; Bone Marrow Transplantation; Caspase Inhibitors; Cell Count; Cysteine Proteinase Inhibitors; Disease Models, Animal; Drug Administration Routes; Graft Survival; Infarction, Middle Cerebral Artery; Male; Neuroprotective Agents; Rats; Rats, Wistar; Recovery of Function; Stromal Cells; Treatment Outcome

Few therapeutic treatment options are available for patients suffering from metastatic androgen-independent prostate cancer. We investigated the ability of the estrogen metabolite 2-methoxyestradiol to inhibit the proliferation of a variety of human prostate cancer cell lines in vitro and to inhibit the growth of androgen-independent prostate cancer in a transgenic mouse model in vivo. Our results showed that 2-methoxyestradiol is a powerful growth inhibitor of LNCaP, DU 145, PC-3, and ALVA-31 prostate cancer cells. Cell flow cytometry of 2-methoxyestradiol-treated DU 145 cells showed a marked accumulation of cells in the G2/M phase of the cell cycle and an increase in the sub-G1 fraction (apoptotic). In addition, staining for annexin V, changes in nuclear morphology, and inhibition of caspase activity support a role for apoptosis. More importantly, we showed that 2-methoxyestradiol inhibits prostate tumor progression in the Ggamma/T-15 transgenic mouse model of androgen-independent prostate cancer without toxic side effects. These results in cell culture and an animal model support investigations into the clinical use of 2-methoxyestradiol in patients with androgen-independent prostate cancer.

Topics: 2-Methoxyestradiol; Administration, Oral; Amino Acid Chloromethyl Ketones; Animals; Annexin A5; Antineoplastic Agents; Apoptosis; Caspase Inhibitors; Cell Division; Cell Nucleus; Disease Models, Animal; Disease Progression; Dose-Response Relationship, Drug; Drug Implants; Drug Resistance, Neoplasm; Enzyme Inhibitors; Estradiol; Flow Cytometry; G2 Phase; Humans; Male; Mice; Mice, Transgenic; Mitosis; Prostatic Neoplasms; Tumor Cells, Cultured

Systemic lupus erythematosus (SLE) is a common, potentially fatal, non-organ-specific autoimmune disorder. Immune complex-mediated kidney disease is the major cause of mortality. Apoptotic cells in the epidermis are a possible source of self Ags, and apoptosis of endothelial cells and lymphocytes is thought to contribute to end-organ damage. We have previously shown that female transgenic mice expressing IFN-gamma in the epidermis develop inflammatory skin disease and features of SLE that have striking parallels with the human condition. We have now tested the effects of a pan-caspase inhibitor, carbobenzoxy-valyl-alanyl-aspartyl-(beta-o-methyl)-fluoromethylketone, on disease progression. Daily s.c. administration of carbobenzoxy-valyl-alanyl-aspartyl-(beta-o-methyl)-fluoromethylketone to female transgenic mice over a 3-wk period resulted in significant amelioration of both glomerular and interstitial renal damage, independent of the effects on autoantibody levels or skin inflammation. We propose that apoptosis inhibitors could be beneficial in the treatment of human SLE.

Topics: Amino Acid Chloromethyl Ketones; Animals; Antibodies, Antinuclear; Autoantibodies; Caspase Inhibitors; Cysteine Proteinase Inhibitors; Disease Models, Animal; Female; Histones; Humans; Interferon-gamma; Kidney; Lupus Erythematosus, Systemic; Lupus Nephritis; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; Skin

Transgenic Huntington's disease (HD) mice, expressing exon 1 of the HD gene with an expanded CAG repeat, are totally resistant to striatal lesion induced by excessive NMDA receptor activation. We now show that striatal lesions induced by the mitochondrial toxin malonate are reduced by 70-80% in transgenic HD mice compared with wild-type littermate controls. This occurred in 6- and 12-week-old HD mice with 150 CAG repeats (line R6/2) and in 18-week-old, but not 6-week-old, HD mice with 115 CAG repeats (line R6/1). Therefore, we show for the first time that the resistance to neurotoxin in transgenic HD mice is dependent on both the CAG repeat length and the age of the mice. Importantly, most HD patients develop symptoms in adulthood and exhibit an inverse relationship between CAG repeat length and age of onset. Transgenic mice expressing a normal CAG repeat (18 CAG) were not resistant to malonate. Although endogenous glutamate release has been implicated in malonate-induced cell death, glutamate release from striatal synaptosomes was not decreased in HD mice. Malonate-induced striatal cell death was reduced by 50-60% in wild-type mice when they were treated with either the NMDA receptor antagonist MK-801 or the caspase inhibitor zVAD-fmk. These two compounds did not reduce lesion size in transgenic R6/1 mice. This might suggest that NMDA receptor- and caspase-mediated cell death pathways are inhibited and that the limited malonate-induced cell death still occurring in HD mice is independent of these pathways. There were no changes in striatal levels of the two anti cell death proteins Bcl-X(L) and X-linked inhibitor of apoptosis protein (XIAP), before or after the lesion in transgenic HD mice. We propose that mutant huntingtin causes a sublethal grade of metabolic stress which is CAG repeat length-dependent and results in up-regulation over time of cellular defense mechanisms against impaired energy metabolism and excitotoxicity.

Topics: Aging; Amino Acid Chloromethyl Ketones; Animals; bcl-X Protein; Blood Glucose; Cell Death; Corpus Striatum; Disease Models, Animal; Dizocilpine Maleate; Excitatory Amino Acid Antagonists; Female; Glutamic Acid; Humans; Huntingtin Protein; Huntington Disease; Immunoblotting; Immunohistochemistry; Male; Malonates; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; Nerve Tissue Proteins; Neurons; Neuroprotective Agents; Nuclear Proteins; Proteins; Proto-Oncogene Proteins c-bcl-2; Succinate Dehydrogenase; Synaptosomes; Trinucleotide Repeats; X-Linked Inhibitor of Apoptosis Protein

Some infarcted myocytes undergo caspase-dependent DNA fragmentation, but serine protease-dependent DNA fragmentation may also be involved. There is controversy regarding whether caspase inhibitors can reduce infarct size, so the present study investigated whether serine protease inhibitor can reduce the DNA fragmentation of infarcted myocytes and whether serine protease or caspase inhibitors attenuates myocardial infarct size in Japanese white rabbits without collateral circulation. Rabbits were subjected to 30-min coronary occlusion followed by 48-h reperfusion. A vehicle (dimethylsulfoxide, control group, n=8) or Z-Val-Ala-Asp(Ome)-CH2F (ZVAD-fmk, a caspase inhibitor, ZVAD group, 0.8 mg/kg iv at 20 min before coronary occlusion and 0.8 mg/kg at 90 min after reperfusion, n=8) or 3,4-dichloroisocoumarin (DCI, a serine protease inhibitor, 2 mg/kg iv at 20 min before coronary occlusion, DCI group, n=8) was administered. Animals were killed at 48h after reperfusion for the detection of myocardial infarct size and at 4h after reperfusion for the detection of dUTP nick end-labeling (TUNEL)-positive myocytes, the electrophoretic pattern of DNA fragmentation and ultrastructural analysis. The left ventricle (LV) was excised and sliced. The myocardial infarct size as a percentage of the area at risk was assessed by triphenyltetrazolium chloride staining. DNA fragmentation was assessed by in situ TUNEL at the light microscopic level. ZVAD and DCI significantly reduced the mean blood pressure during reperfusion without affecting heart rate. There was no significant difference in the % area at risk (AAR) of LV among the 3 groups (control: 26.3+/-3.0%; ZVAD: 25.6+/-2.6%; DCI: 25.6+/-2.0%). The % infarct size as a percentage of the AAR in the ZVAD group (41.3+/-4.5%) and the DCI group (50.4+/-3.8%) was not significantly different from the control group (43.5+/-4.5%). However, the percent DNA fragmentation in the infarcted area in the ZVAD (3.5+/-0.8%) and DCI groups (4.2+/-0.9%) was significantly reduced compared with the control group (10.7+/-1.9%). The DNA ladder pattern observed in the control group was attenuated in both the ZVAD and DCI groups. There was no difference in electron microscopic changes among the 3 groups. Serine protease-dependent DNA fragmentation is present in infarcted myocytes, in addition to caspase-dependent DNA fragmentation, but an infarct-size reducing effect was not observed with either of these inhibitors.

Topics: Amino Acid Chloromethyl Ketones; Animals; Caspase Inhibitors; Caspases; Disease Models, Animal; DNA Fragmentation; Enzyme Inhibitors; In Situ Nick-End Labeling; Male; Microscopy, Electron; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion; Myocardium; Rabbits; Serine Proteinase Inhibitors

Mutations in the copper/zinc superoxide dismutase (SOD1) gene produce an animal model of familial amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder. To test a new therapeutic strategy for ALS, we examined the effect of caspase inhibition in transgenic mice expressing mutant human SOD1 with a substitution of glycine to alanine in position 93 (mSOD1(G93A)). Intracerebroventricular administration of zVAD-fmk, a broad caspase inhibitor, delays disease onset and mortality. Moreover, zVAD-fmk inhibits caspase-1 activity as well as caspase-1 and caspase-3 mRNA up-regulation, providing evidence for a non-cell-autonomous pathway regulating caspase expression. Caspases play an instrumental role in neurodegeneration in transgenic mSOD1(G93A) mice, which suggests that caspase inhibition may have a protective role in ALS.

Topics: Amino Acid Chloromethyl Ketones; Amino Acid Substitution; Amyotrophic Lateral Sclerosis; Animals; Apoptosis; Caspase 1; Caspase 3; Caspase Inhibitors; Caspases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Disease Progression; Enzyme Activation; Gene Expression Regulation, Enzymologic; Humans; Injections, Intraventricular; Interleukin-1; Male; Mice; Mice, Transgenic; Motor Neurons; Nerve Degeneration; Neuroprotective Agents; Psychomotor Performance; Spinal Cord; Superoxide Dismutase; Superoxide Dismutase-1

Topics: Amino Acid Chloromethyl Ketones; Amyotrophic Lateral Sclerosis; Animals; Apoptosis; Caspase 1; Caspase 3; Caspase Inhibitors; Caspases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Humans; Interleukin-1; Mice; Mice, Transgenic; Motor Neurons; Neuroprotective Agents; Spinal Cord; Superoxide Dismutase; Superoxide Dismutase-1

The differentiated cells seem to share the ability to induce their own death by the activation of an internally encoded suicide program. When activated, this suicide program initiates a characteristic form of cell death called apoptosis. A central challenge in apoptosis research is understanding the mechanisms by which apoptotic cascades are initiated and affected. We tested a potential role for calpain in the programmed cell death under ischemic conditions and found that calpain is (1) activated at a time preceding morphological changes, DNA fragmentation and death, (2) that calpain is translocated to the nucleus before DNA laddering, (3) pretreatment with caspase inhibitors and/or calpain inhibitors block not only the proteolytic actions of the enzyme, but also the cell death process itself in the CA1 subfield after transient global ischemia in a synergistic manner. In conclusion, the present results contribute additional evidence that proteases may play a functional role in apoptotic cell death and extend them to include the possibility that endogenous proteases are capable of inducing the striking DNA fragmentation and chromatin condensation, which are the principle criteria currently used to define apoptotic death. Moreover, the synergistic effect of caspase and calpain inhibitors in protecting neurons form ischemic damage suggests that there is a cross-talk between caspase and calpain during apoptosis.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Benzenesulfonates; Brain Ischemia; Calpain; Caspase Inhibitors; Caspases; Coloring Agents; Cysteine Proteinase Inhibitors; Disease Models, Animal; DNA Fragmentation; Drug Combinations; Drug Synergism; Glycoproteins; Hippocampus; Immunohistochemistry; In Situ Nick-End Labeling; Male; Neurons; Neuroprotective Agents; Oxazines; Rats; Rats, Wistar; Reperfusion Injury

Hippocampal neurons from the trisomy 16 (Ts16) mouse, a potential animal model of Down's syndrome (trisomy 21) and neurodegenerative disorders such as Alzheimer's disease (AD), die at an accelerated rate in vitro. Here, we present evidence that the accelerated neuronal death in Ts16 occurs by apoptosis, as has been reported for neurons in AD. First, the nuclei of dying Ts16 neurons are pyknotic and undergo DNA fragmentation, as revealed by terminal transferase-mediated dUTP nick end-labeling. Second, the accelerated death of Ts16 neurons is prevented by inhibitors of the caspase family of proteases, which are thought to act at a late, obligatory step in the apoptosis pathway. In the presence of maximally effective concentrations of caspase inhibitors, Ts16 neuron survival was indistinguishable from that of control neurons. These results suggest that overexpression of one or more genes on mouse chromosome 16 leads to caspase-mediated apoptosis in Ts16 neurons.

Topics: Alzheimer Disease; Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Caspases; Cells, Cultured; Cysteine Proteinase Inhibitors; Disease Models, Animal; Down Syndrome; Female; In Situ Nick-End Labeling; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Nerve Degeneration; Neurons; Oligopeptides; Pregnancy; Trisomy

Z-Val-Ala-Asp(OMe)-CH2F (ZVAD-fmk), a tripeptide inhibitor of the caspase interleukin-1beta-converting enzyme family of cysteine proteases, may reduce myocardial reperfusion injury in vivo by attenuating cardiomyocyte apoptosis within the ischemic area at risk.. Sprague-Dawley rats were subjected to a 30-minute coronary occlusion followed by a 24-hour reperfusion. An inert vehicle (dimethylsulfoxide; group 1, n=8) or ZVAD-fmk, at a total dose of 3.3 mg/kg (group 2, n=8), was administered intravenously every 6 hours starting at 30 minutes before coronary occlusion until 24 hours of reperfusion. At this 24-hour point, hemodynamics were assessed by means of cardiac catheterization; then, the rats were killed, and the left ventricle was excised and sliced. The myocardial infarct size/ischemic area at risk and the count of presumed apoptotic cardiomyocytes (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling [TUNEL]-positive cells) within the ischemic area at risk were assessed through triphenyltetrazolium chloride staining and TUNEL methods, respectively. Peak positive left ventricular dP/dt was higher (P=.02) and left ventricular end-diastolic pressure was lower (P=.04) in group 2 than in group 1. The infarct size/ischemic area at risk of group 2 (52.4+/-4.0%) was smaller (P=.02) than that of group 1 (66.6+/-3.7%), and TUNEL-positive cells were fewer (P=.0002) (group 2, 3.1+/-0.9%; group 1, 11.1+/-1.0%). Agarose gel electrophoresis revealed DNA laddering in the border zone myocardium of group 1, but DNA ladder formation was attenuated in group 2.. ZVAD-fmk was effective in reducing myocardial reperfusion injury, which could at least be partially attributed to the attenuation of cardiomyocyte apoptosis.

Topics: Amino Acid Chloromethyl Ketones; Animals; Cysteine Endopeptidases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Electrophoresis, Agar Gel; Genetic Techniques; Heart; Hemodynamics; Leukocyte Count; Male; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion Injury; Myocardium; Rats; Rats, Sprague-Dawley

The objective of the present study was to determine the effects of concanavalin A (Con A) administration on the interleukin 1beta converting enzyme (ICE) activity and CPP32-like activity in mouse liver. Treatment with Con A (0.2 mg/mouse, i.v.) caused an elevated plasma alanine aminotransferase (ALT) level at 8 hr after Con A injection. ICE activity was decreased at 8 and 24 hr after Con A treatment. In contrast, CPP32-like activity was increased at 24 hr after Con A injection. Since CPP32-like activity was induced after ALT had increased, the induction of CPP32-like activity may not be involved in Con A-induced hepatitis.

Topics: Amino Acid Chloromethyl Ketones; Animals; Caspase 1; Caspase 3; Caspases; Chemical and Drug Induced Liver Injury; Concanavalin A; Cysteine Proteinase Inhibitors; Disease Models, Animal; Enzyme Induction; Female; Liver; Mice; Mice, Inbred BALB C