• Korean Journal of Biological Psychiatry
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• v.5 no.2
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• pp.219-226
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• 1998

Cytosine arabinoside(AraC) inhibits DNA synthesis and ${\beta}$-DNA polymerase, an enzyme involved in DNA repair. This, a potent antimitotic agent, is clinically used as an anticancer drug with side effect of severe neurotoxicity. Earlier reports suggested that inhibition of neuronal survival by AraC in sympathetic neuron may be due to the inhibition of a 2'-deoxycytidine-dependent process that is independent of DNA synthesis or repair and AraC induced a signal that is triggers a cascade of new mRNA and protein synthesis, leading to apoptotic cell death in cultured cerebellar granule cells. The present study would suggest whether caspase family(ICE/CED-3-like protease) involved in AraC-induced apoptosis pathway of PC12 cells. It was observed that treatment of PC12 cells with AraC led to decrease of viability by MTT assay and morphology changes, which did not suggest that AraC induced apoptosis in PC12 cells. The mRNA of caspase-1/caspase-3 were expressed in PC12 cells constitutively, and AraC did not activate caspase family. These results suggest that caspase-1/caspase-3 may not be required for AraC-induced cell death pathway in PC12 cells.

• Journal of International Academy of Physical Therapy Research
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• v.5 no.2
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• pp.718-722
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• 2014

The cerebellum is known to control balance, equilibrium, and muscle tone. If the cerebellum becomes damaged, the body is unable to retain its balancing functions or involuntary muscle movement. This is why, in stroke patients, there is a high risk of functional disability, as well as a myriad of other disabilities secondary to stroke. Ischemia was induced in SD mice by occluding the common carotid artery for 5 minutes, after which blood was reperfused. Needle electrode electrical stimulation(NEES) was applied to acupuncture points, at 12, 24, and 48 hours post-ischemia on the joksamri. Protein expression was investigated through caspase-3 antibody immuno-reactive cells in the cerebral nerve cells and Western blotting. The results were as follows: The number of caspase-3 reactive cells in the corpus cerebellum 12 and 24 hours post-ischemia was significantly (p<.05) smaller in the NEES group compared to the GI group. caspase-3 expression 12 and 24 hours post-ischemia was significantly(p<.05) smaller in the NEES group compared to the GI group. Based on these results, NEES seems to have a significant effect on Caspase-3 in the cerebellum in an ischemic state at 12 and 24 hours post ischemia, NEES delays the occurrence of early stage apoptosis-inducing Caspase-3, delaying and inhibiting apoptosis. Further systematic studies will have to be conducted in relation to the application of this study's results on stroke patients.

• Animal cells and systems
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• v.12 no.3
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• pp.127-136
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• 2008

Caspase-11 has been known as a dual regulator of cytokine maturation and apoptosis. Although the role of caspase-11 under pathological conditions has been well documented, its physiological role has not been studied much. In the present study, we investigated a possible physiological function of caspase-11 during immune response. In the absence of caspase-11, immunized spleen displayed increased cellularity and abnormal germinal center structure with disrupted microarchitecture. The rate of cell proliferation and apoptosis in the immunized spleen was not changed in the caspase-11-deficient mice. Furthermore, the caspase-11-deficient peritoneal macrophages showed normal phagocytotic activity. However, caspase-11-/-splenocytes and macrophages showed defective migrating capacity. The dysregulation of cell migration did not seem to be mediated by caspase-3, interleukin-$1{\alpha}$ or interleukin-$1{\beta}$ which acts downstream of caspase-11. These results suggest that a direct regulation of immune cell migration by caspase-11 is critical for the formation of germinal center microarchitecture during immune response. However, humoral immunity in the caspase-11-deficient mice was normal, suggesting the formation of germinal center structure is not essential for the affinity maturation of the antibodies.

• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.1034-1040
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• 2022

Fas-associated death domain (FADD) is an adapter molecule that bridges the interaction between receptor-interacting protein 1 (RIP1) and aspartate-specific cysteine protease-8 (caspase-8). As the primary mediator of apoptotic cell death, caspase-8 has two N-terminal death-effector domains (DEDs) and it interacts with other proteins in the DED subfamily through several conserved residues. In the tumor necrosis receptor-1 (TNFR-1)-dependent signaling pathway, apoptosis is triggered by the caspase-8/FADD complex by stimulating receptor internalization. However, the molecular mechanism of complex formation by the DED proteins remains poorly understood. Here, we found that direct DED-DED interaction between FADD and caspase-8 and the structure-based mutations (Y8D/I128A, E12A/I128A, E12R/I128A, K39A/I128A, K39D/I128A, F122A/I128A, and L123A/I128A) of caspase-8 disrupted formation of the stable DED complex with FADD. Moreover, the monomeric crystal structure of the caspase-8 DEDs (F122A/I128A) was solved at 1.7 Å. This study will provide new insight into the interaction mechanism and structural characteristics between FADD and caspase-8 DED subfamily proteins.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.521-528
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• 2017

Excessive alcohol consumption is one of the leading causes of many neurological diseases, such as dementia and Alzheimer's disease, and many efforts are under way to solve them. Red ginseng is known to enhance neuronal survival, inhibit apoptosis, and promote nerve regeneration of nerve cells. This study examined whether Rg3-enriched Korean red ginseng extract (KRG) inhibits the apoptosis of PC12 cells caused by alcohol-induced neurotoxicity and how KRG regulates several factors related to the caspase mediated pathway. In this way, the cell survival rate and apoptosis rate of PC12 cells were measured using an EZ-Cytox cell viability assay kit and flow cytometry, respectively. The expression of the apoptosis-related proteins (Bcl-2, Bid, Bax and caspase-3) were analyzed by western blotting, and the significance of the measured results was confirmed using the ANOVA method. As a result, KRG increased the expression of Bcl-2; inhibited the expression of Bid, Bax, and caspase-3; and inhibited the apoptosis of alcohol-induced PC12 cells. These results mean that the KRG-induced increase in Bcl-2 expression and down-regulation of Bid and Bax expression down-regulate caspase-3 expression, which in turn inhibits the mitochondrial apoptotic pathways. This study suggests that KRG is worth developing as a neuroprotective agent candidate.

• BMB Reports
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• v.46 no.12
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• pp.588-593
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• 2013

Apoptosis, programmed cell death, is a process involved in the development and maintenance of cell homeostasis in multicellular organisms. It is typically accompanied by the activation of a class of cysteine proteases called caspases. Apoptotic caspases are classified into the initiator caspases and the executioner caspases, according to the stage of their action in apoptotic processes. Although caspase-3, a typical executioner caspase, has been studied for its mechanism and substrates, little is known of caspase-6, one of the executioner caspases. To understand the biological functions of caspase-6, we performed proteomics analyses, to seek for novel caspase-6 substrates, using recombinant caspase-6 and HepG2 extract. Consequently, 34 different candidate proteins were identified, through 2-dimensional electrophoresis/MALDI-TOF analyses. Of these identified proteins, 8 proteins were validated with in vitro and in vivo cleavage assay. Herein, we report that HAUSP, Kinesin5B, GEP100, SDCCAG3 and PARD3 are novel substrates for caspase-6 during apoptosis.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.88.1-88.1
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• 2008

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.88.2-88.2
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• 2008

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.103-112
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• 2009

Objectives : This study was to evaluate the pharmacological effect of Korea Red Ginseng aqueous extract (KRGE) on serum-deprived apoptosis of neuronal-like pheochromocytoma PC12 cells and to investigate its underlying action mechanism. Methods : KRGE was prepared by extracting Korea Red Ginseng with hot water and concentrating using a vacuum evaporator. Cell viability was determined after incubation of cells with KRGE or chemical inhibitor in serum-deprived medium for 60 h by counting intact nuclei following lysing of the cell membrane. Caspase activities were measured using chromogenic substrates and signal-associated protein phosphorylation and cytochrome c release were determined by Western blot analyses using their specific antibodies. Results : Serum deprivation induced PC12 cell death, which was accompanied by typical morphological features of apoptotic cell, such as nuclear fragmentation, caspase-3 activation, and cytochrome c release. This apoptotic cell death was significantly inhibited by KRGE and caspase-3 inhibitor, but not by the addition of NMA, ODQ, and PD98059. KRGE promoted phosphorylation of Akt and Bad, and this phosphorylation was inhibited by the PI3K inhibitor LY92004. In addition, this inhibitor also reversed KRGE-mediated protection of PC 12 cells from serum deprivation. These results suggested that KRGE protects PC12 cells from serum deprivation-induced apoptosis through the activation of PI3K/Akt-dependent Bad phosphorylation and cytochrome c release, resulting in caspase-3 activation. Conclusions : KRGE should be considered as a potential therapeutic drug for brain diseases including stroke induced by apoptosis of neuronal cells.

• Journal of Integrative Natural Science
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• v.7 no.1
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• pp.25-38
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• 2014

Amyloid-${\beta}$-peptide ($A{\beta}$) is important in the pathogenesis of Alzheimer's disease (AD). Calpain ($Ca^{2+}$-dependent protease) and caspase-8 (the initiating caspase for the extrinsic, receptor-mediated apoptosis pathway) have been implicated in $AD/A{\beta}$ toxicity. We found that $A{\beta}$ promoted degradation of calpastatin (the specific endogenous calpain inhibitor); calpastatin degradation was prevented by inhibitors of either calpain or caspase-8. The results implied a cross-talk between the two proteases and suggested that one protease was responsible for the activity of the other one. In neuron-like differentiated PC12 cells, calpain promotes active caspase-8 formation from procaspase-8 via the $A{\beta}$ and CD95 pathways, along with degradation of the procaspase-8 processing inhibitor caspase-8 (FLICE)-like inhibitory protein, short isoform (FLIPS). Inhibition of calpain (by pharmacological inhibitors and by overexpression of calpastatin) prevents the cleavage of procaspase-8 to mature, active caspase-8, and inhibits FLIPS degradation in the $A{\beta}$-treated and CD95-triggered cells. Increased cellular Ca2+ per se results in calpain activation but does not lead to caspase-8 activation or FLIPS degradation. The results suggest that procaspase-8 and FLIPS association with cell membrane receptor complexes is required for calpain-induced caspase-8 activation. The results presented here add to the understanding of the roles of calpain, caspase- 8, and CD95 pathway in $AD/A{\beta}$ toxicity. Calpain-promoted activation of caspase-8 may have implications for other types of CD95-induced cell damage, and for nonapoptotic functions of caspase-8. Inhibition of calpain may be useful for modulating certain caspase-8-dependent processes.