• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.195-200
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• 2011

Neuronal cell death is a common characteristic feature of a variety of neurodegenerative disorders including Alzheimer's disease and Parkinson's disease. However, there have been no effective drugs to successfully prevent neuronal death in those diseases. In the present study, docosyl cafferate (DC), a derivative of caffeic acid, was isolated from Rhus verniciflua and its protective effects on tBHP-induced neuronal cell death were examined in SH-SY5Y human neuroblastoma cells. Pretreatment of DC significantly attenuated tBHP-induced neuronal cell death in a concentration-dependent manner. DC also significantly suppressed tBHP-induced caspase-3 activation. In addition, DC restored tBHP-induced depletion of intracellular Bcl-2, an anti-apoptotic member of the Bcl-2 family. Furthermore, DC significantly suppressed tBHP-induced degradation of IKB, which retains $NF-{\kappa}B$ in the cytoplasm, resulting in the suppression of nuclear translocation of $NF-{\kappa}B$ and its subsequent activation. Taken together, the results clearly demonstrate that DC exerts its neuroprotective activity against tBHP-induced oxidative stress through the suppression of nuclear translocation of $NF-{\kappa}B$.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.1
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• pp.29-44
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• 2005

To address the ability of Herba Portulacae(HP) to induce cell death, we investigated the effect of HP on cell viability. Twenty-four hours later, loss of viability occurred following HP exposure in a dose-dependent manner. The treatment of HP, a commonly used herb formulation in Korea, Japan and China, caused a decrease in cell viability. HP also resulted in apoptotic morphology a brightly blue-fluorescent condensed nuclei by Hoechst 33258-staining, and reduction of cell volume. Our results show that 2mg/ml HP induces mitochondria membrane potential collapse. Immunoblotting data also shows that the expression of Bcl-2, antiaoptotic protein, decrease by the addition of HP. This GFP-Bax overexpression system shows that an important pro-apoptotic Bcl-2-family protein, Bax is translocated to mitochondria by the addition of 2mg/ml HP. Inerestingly, MAPK inhibitor study shows that p38 MAPK inhibitor, SB203580 inhibits HP-induced cell death and caspase-3 activation in HP-treated HeLa cells. Furthermore, HP transiently but significantly induces p38 activation. But P38 MAPK inhibitor does not have any effect on the translocation of Bax. Considering these results, HP induces apoptosis via p38 MAPK activation. But the pathway does not involve the translocation of Bax.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1253-1257
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• 2004

6-Methoxydihydrosanguinarine (6ME), a benzophenanthridine alkaloid derived from the methanol extracts of Hylomecon hylomeconoides, showed a dose-dependent effect at 1-10 ${\mu}M$ on causing apoptotic cell death in HT29 colon carcinoma cells $(IC_{50} = 5.0{\pm}0.2 {\mu}M)$. Treatment of HT-29 cells with 6ME resulted in the formation of internucleosomal DNA fragmentation. Treatment of the cells with 6ME caused activation of caspase-3, -8 and 9 protease and subsequent proteolytic cleavage of poly(ADP-ribose)polymerase. 6ME increased the expression of p53 and Bax and decreased the expression of Bid. These results indicate that p53 and proapoptotic Bcl-2 family proteins might participate in the antiproliferative activity of 6ME in HT29 cells.

• Korean Journal of Head & Neck Oncology
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• v.18 no.2
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• pp.142-149
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• 2002

Objectve : Okadaic acid is a specific inhibitor of serine/threonine protein phosphatase 1 and 2A. In order to know the mechanism of apoptosis induced by okadaic acid, we treated FRTL-5 thyroid cells with okadaic acid and measured the changes of important proteins that are involved in apoptosis. Materials and Methods: We measured caspase 3 activity, $PLC-{\gamma}1$ degradation, the expression of XIAP, cIAP1, cIAP2, and cytochrome c release in okadaic acid-treated FRTL-5 thyroid cells. Results: Okadaic acid-induced caspase 3 activation and $PLC-{\gamma}1$ degradation and apoptosis were dose-dependent with a maximal effect at a concentration of 80 nmol and time-dependent with a maximal effect at 24 hours after treatment. The elevated caspase 3 activity in okadaic acid treated FRTL-5 thyroid cells are correlated with down-regulation of XIAP and cIAP1, but not cIAP2. General and potent inhibitor of caspases, z-VAD-fmk. abolished okadaic acid-induced caspase 3 activity and $PLC-{\gamma}1$ degradation. The release of cytochrome c in okadaic acid-induced FRTL-5 thyroid cells was dose-dependent with a maximal effect at a concentration of 80 nmol. Conclusions: These findings suggest that mechanism of okadaic acid-induced apoptosis is associated with cytochrome c release and increase of caspase 3 activation in FRTL-5 thyroid cells.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.279-286
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• 2020

Purple loosestrife-Lythrum anceps (Koehne) Makino is a herbaceous perennial plant belonging to the Lythraceae family. It has been used for centuries in Korea and other Asian traditional medicine. It has been showed pharmacological effects, including anti-oxidant and anti-microbial effects. However, the mechanisms underlying its anti-cancer effect are not yet understood. In this study, we investigated the mechanism of apoptosis signaling pathways by ethanol extract of Lythrum anceps (Koehne) Makino (ELM) in human leukemia U937 cells. Treatment with ELM significantly inhibited cell growth in a dose-dependent manner by inducing apoptosis, as evidenced by the formation of apoptotic bodies (ApoBDs), DNA fragmentation and increased populations of sub-G1 ratio. Induction of apoptosis by ELM was connected with up-regulation of death receptor (DR) 4 and DR5, pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic Bcl-2 protein, and inhibitor of apoptosis protein (IAP) family proteins, depending on dosage. This induction was associated with Bid truncation, mitochondrial dysfunction, proteolytic activation of caspases (-3, -8 and -9) and cleavage of poly(ADP-ribose) polymerase protein. Therefore, our data indicate that ELM suppresses U937 cell growth by activating the intrinsic and extrinsic apoptosis pathways, and thus may have applications as a potential source for an anti-leukemic chemotherapeutic agent.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.2
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• pp.553-560
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• 2004

In the present study, we investigated the anti-proliferative effects of aqueous extract of Wikyung-tang(WKT) on the growth of human lung carcinoma cell line A549. WKT treatment declined the cell viability and proliferation of A549 cells in a concentration-dependent manner. The anti-proliferative effects by WKT treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. WKT treatment induced an inhibition and/or degradation of apoptotic target proteins such poly(ADP-ribose) polymerase (PARP) and phospholipase C-γ1 (PLC-γ1). WKT treatment did not affect the levels of other Bcl-2 family gene products, such as Bcl-2, Bax and Bad. Western blot analysis and RT-PCT data revealed that the levels of tumor suppressor p53 and cyclin-dependent kinase inhibitor p21 were induced by WKT treatment in A549 cells. Additionally, WKT treatment induced the down-regulation of telomerase reverse transcriptase mRNA (hTERT) expression of A549 cells, however, the levels of other telomere-regulatory gene products were not affected. Taken together, these findings suggest that WKT-induced inhibition of human lung cancer cell proliferation is associated with the induction of apoptotic cell death via regulation of several major growth regulatory gene products and WKT may have therapeutic potential in human lung cancer.

• Journal of Veterinary Science
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• v.23 no.2
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• pp.26.1-26.12
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• 2022

Background: Glutamate is the main excitatory neurotransmitter. Excessive glutamate causes excitatory toxicity and increases intracellular calcium, leading to neuronal death. Parvalbumin is a calcium-binding protein that regulates calcium homeostasis. Quercetin is a polyphenol found in plant and has neuroprotective effects against neurodegenerative diseases. Objectives: We investigated whether quercetin regulates apoptosis by modulating parvalbumin expression in glutamate induced neuronal damage. Methods: Glutamate was treated in hippocampal-derived cell line, and quercetin or vehicle was treated 1 h before glutamate exposure. Cells were collected for experimental procedure 24 h after glutamate treatment and intracellular calcium concentration and parvalbumin expression were examined. Parvalbumin small interfering RNA (siRNA) transfection was performed to detect the relation between parvalbumin and apoptosis. Results: Glutamate reduced cell viability and increased intracellular calcium concentration, while quercetin preserved calcium concentration and neuronal damage. Moreover, glutamate reduced parvalbumin expression and quercetin alleviated this reduction. Glutamate increased caspase-3 expression, and quercetin attenuated this increase in both parvalbumin siRNA transfected and non-transfected cells. The alleviative effect of quercetin was statistically significant in non-transfected cells. Moreover, glutamate decreased bcl-2 and increased bax expressions, while quercetin alleviated these changes. The alleviative effect of quercetin in bcl-2 family protein expression was more remarkable in non-transfected cells. Conclusions: These results demonstrate that parvalbumin contributes to the maintainace of intracellular calcium concentration and the prevention of apoptosis, and quercetin modulates parvalbumin expression in glutamate-exposed cells. Thus, these findings suggest that quercetin performs neuroprotective function against glutamate toxicity by regulating parvalbumin expression.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.5043-5047
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• 2014

Nowadays increasing effectiveness in cancer therapy and investigation of formation of new strategies that enhance antiproliferative activity against target organs has become a subject of interest. Although the molecular mechanisms of apoptosis can not be fully explained, it is known that cell suicide program existing in their memory genetically is activated by pathophysiological conditions and events such as oxidative stress. Low pressure (hypobaric) conditions that create hypoxia promote apoptosis by inhibiting cell cycling. In this study, determination of the effects of fractional hypobaric applications at different times on HeLa cells at cellular and molecular levels were targeted. Experiments were carried out under hypobaric conditions (35.2 kPa) in a specially designed hypobaric cabin including 2% $O_2$ and 98% N. Application of fractional hypobaric conditions was repeated two times for 3 hours with an interval of 24 hours. At the end of the implementation period cells were allowed to incubate for 24 hours for activation of repair mechanisms. Cell kinetic parameters such as growth rate (MTT) and apoptotic index were used in determination of the effect of hypobaric conditions on HeLa cells. Also in our study expression levels of the Bcl-2 gene family that have regulatory roles in apoptosis were determined by the RT-PCR technique to evaluate molecular mechanisms. The results showed that antiproliferative effect of hypobaric conditions on HeLa cells started three hours from the time of application and increased depending on the period of exposure. While there was a significant decrease in growth rate values, there was a significant increase in apoptotic index values (p<0.01). Also molecular studies showed that hypobaric conditions caused a significant increase in expression level of proapoptotic gene Bax and significant decrease in antiapoptotic Bfl-1. Consequently fractional application of hypobaric conditions on HeLa cell cultures increased both antiproliferative and apoptotic effects and these effects were triggered by the Bax gene.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.207-214
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• 2008

In Asia Saussurea lappa (SL) has been used as a traditional herbal medicine to treat abdominal pain and tenesmus. Recently, in vitro cell culture studies have shown that SL has anti-ulcer, anti-inflammatory, and anti-tumor properties. To explore its potential chemopreventive and chemotherapeutic effects in colon cancer, we examined whether the hexane extract of SL (HESL) could inhibit the growth of HT-29 human colon cancer cells, and investigated the mechanisms for this effect. The cells were cultured with various concentrations (0-5 ${\mu}g/mL$) of HESL. The results indicated that HESL markedly decreased the numbers of viable HT-29 cells; whereas at the concentration of 5 ${\mu}g/mL$, HESL slightly decreased the viable cell numbers of CCD 1108Sk human skin normal fibroblasts at 72 hr. HESL substantially increased the numbers of cells in the sub G1 phase, and dose-dependently increased apoptotic cell numbers. Western blot analysis of the total cell lysates revealed that HESL increased Bax protein levels, but did not affect Bcl-2 levels. HESL induced the cleavage of poly (ADP-ribose) polymerase and caspases 8, 9, 7, and 3. This study demonstrated that HESL inhibits cell growth and induces apoptosis in HT-29 cells, which may be mediated by its ability to increase Bax levels and activate the caspase pathway. These findings may lead to the development of new therapeutic strategies for colon cancer treatment.

• Korean Journal of Pharmacognosy
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• v.32 no.4 s.127
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• pp.274-279
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• 2001

Ailanthus altissima belonging to the family Simaroubaceae has been used to settle an upset stomach, to combat a fever, and as an insecticide. Apoptosis is an active process, which is a critical feature of the regulated development of multicellular organisms. We investigated whether the extract of A. altissima induced apoptotic cell death in Jurkat T-acute lymphoblastic leukemia (ALL) cells. Upon treatments with the extract, the dose-dependent inhibitions of cell viability were observed. It also caused apoptosis as measured by cell morphology and DNA fragmentation. The capability of the extract to induce apoptosis was associated with proteolytic cleavage of specific target protein such as poly(ADP-ribose)polymerase (PARP) protein, suggesting the possible involvement of the activations of caspases. Further study showed that Bcl-2 protein levels were not changed in all treated groups compared to control group. These results suggest that A. altissima induces Bcl- 2-independent apoptosis in Jurkat T cells.