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1.
Biomedical and Environmental Sciences ; (12): 494-504, 2016.
Artículo en Inglés | WPRIM | ID: wpr-296577

RESUMEN

<p><b>OBJECTIVE</b>To investigate the role of autophagy in MnCl2-induced apoptosis in human bronchial epithelial 16HBE cells.</p><p><b>METHODS</b>Cell proliferation was measured by MTT assay. Mitochondrial membrane potential (MMP) and apoptosis were measured by flow cytometry. Autophagic vacuoles were detected by fluorescence microscopy. Cellular levels of apoptosis and autophagy-related proteins were measured by western blotting.</p><p><b>RESULTS</b>16HBE cell proliferation was inhibited by MnCl2 in a dose- and time-dependent manner. MnCl2-induced 16HBE cell growth inhibition was related to MMP depolarization prior to the induction of apoptosis. Our data revealed that MnCl2-induced apoptosis in 16HBE cells was mediated by decreased expression of Bcl-2 and increased levels of cleaved caspase-3. It was observed that when we exposed 16HBE cells to MnCl2 in a dose-dependent manner, the formation of autophagic vacuoles and the levels of LC-3B-II were elevated. RNA interference of LC3B in these MnCl2-exposed cells demonstrated that MMP loss and apoptosis were enhanced. Additionally, the pan-caspase inhibitor Z-VAD-FMK increased the cellular levels of Bcl-2 and decreased apoptosis, but did not affect the cellular levels of LC3B in MnCl2-treated 16HBE cells.</p><p><b>CONCLUSION</b>MnCl2 dose- and time-dependently inhibits 16HBE cell proliferation and induces MMP loss and apoptosis. Autophagy acts in a protective role against MnCl2-induced apoptosis in 16HBE cells.</p>


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos , Farmacología , Apoptosis , Autofagia , Fisiología , Bronquios , Línea Celular , Cloruros , Farmacología , Regulación hacia Abajo , Células Epiteliales , Regulación de la Expresión Génica , Compuestos de Manganeso , Farmacología
2.
Journal of Experimental Hematology ; (6): 1623-1627, 2015.
Artículo en Chino | WPRIM | ID: wpr-272549

RESUMEN

<p><b>OBJECTIVE</b>To investigate the effects of FTY720 on apoptosis in multiple myeloma cell line U266 and to clarify the molecular mechanism of apoptosis induced by FTY720.</p><p><b>METHODS</b>U266 cells were treated with 2.5, 5, 10 and 20 µmol/L of FTY720 for 24 hours, the apoptotic rates were tested by flow cytometry with Annexin-V-FITC/PI staining. Then U266 cells were treated with 20 µmol/L FTY720 for 0, 6, 16 and 24 hours, the apoptotic rates were tested. U266 cells were treated with DMSO and FTY720 separately and then were stained with DAPI for 5 min. Drop the cells to the slides and cover the slide with the glass. The cells were observed by fluorescence microscopy. U266 cells were treated with 5 µmol/L FTY720 or together with different doses of Z-VAD-fmk (12.5, 25, 50 µmol/L), a pancaspase inhibitor, for 24 hours, then the cell viability was tested by CCK-8. U266 cells were treated with 2.5, 5, 10 and 20 µmol/L of FTY720 for 24 hours, the expression of cleaved caspase-3 was tested by Western blot. U266 cells were treated with 0, 5, 10 and 20 µmol/L of FTY720 for 24 hours, the expressions of MCL-1, survivin, BCL-2, BID, BAX, BAK, P-ERK were tested by Western blot.</p><p><b>RESULTS</b>The apoptotic rate increased in U266 cells treated with FTY720 and showed the characteristic of time-dependent and dose-dependent manner. Karyopyknosis and nuclearfragmentation could be observed in U266 cells treated with FTY720 after being stained with DAPI under fluorescent microscope. The same effect was not observed in the cells treated with DMSO. Z-VAD-fmk could rescue the apoptosis in U266 cells treated with FTY720 in dose-dependent manner. The expression of MCL-1, survivin and BCL-2 decreased in U266 cells treated with FTY720. The cleavage of BID could be observed in U266 cells treated with FTY720. FTY720 had no effect on the expression of BAX, BAK and P-ERK.</p><p><b>CONCLUSION</b>FTY720 can induce the apoptosis in U266 cells, the apoptosis was Caspase-3-depended. The apoptosis induced by FTY720 is due to the decrease of MCL-1, survivin and BCL-2, which are the inhibitors of apoptosis. Meanwhile, the apoptosis was also due to the activation of BID, which is pro-apoptotic protein.</p>


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos , Apoptosis , Caspasa 3 , Línea Celular Tumoral , Supervivencia Celular , Clorhidrato de Fingolimod , Proteínas Inhibidoras de la Apoptosis , Mieloma Múltiple
3.
Journal of Central South University(Medical Sciences) ; (12): 1292-1297, 2015.
Artículo en Chino | WPRIM | ID: wpr-815338

RESUMEN

OBJECTIVE@#To explore the exact mechanisms of programmed cell death (PCD) induced by Type II anti-CD20 mAb in CD20+ non-Hodgkin lymphoma (NHL) cells, and to provide theoretical basis for anti-tumor ability of new CD20 mAb.
@*METHODS@#After incubation with Rituximab (a Type I anti-CD20 mAb) and Tositumomab (a Type II anti-CD20 mAb), Raji cells were stained by annexin V & propidium iodide (PI). The ratio of programmed death cells were measured by two channel flow cytometry (FCM). Before the treatment of anti-CD20 mAbs, Raji cells was incubated with a caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (Z-VAD-FMK) and a dihydroceramide synthase inhibitor fumonisin B1 (FB1) for 30 minutes to assess their inhibitory effect on PCD. High performance liquid chromatography (HPLC) was utilized to compare the ratio of programmed death cells between the pretreatment group (treated by Rituximab and Tositumomab) and the non-pretreatment group. The anti-CD20 mAbs-treated Raji cells were collected, and the ceramide levels in the Raji cells in the different pretreatment groups were also examined by HPLC, and the inhibitory effect of FB1 on the changes of ceramide levels in the Raji cells was measured. The Raji cells were incubated with different concentration C2-ceramide, C2-Ceramide-induced PCD was also evaluated by annexin V & PI staining after 16 hours. 
@*RESULTS@#Tositumomab (10 µg/mL) but not Rituximab (10 µg/mL) can induce significant PCD (28.6±4.2)% in Raji cells, with significant difference (t=26.48, P0.05). The cellular ceramide levels in Raji cells were significantly elevated after the treatment of Tositumomab (t=28.48, P0.05). The dihydroceramide synthase inhibitor FB1 can significantly inhibit the elevated cellular ceramide levels (F=20.18, P<0.01) and cell programmed death induced by Tositumomab (F=17.02, P<0.01).
@*CONCLUSION@#Type II but not Type I anti-CD20 mAbs can induce caspase independent PCD in CD20+ NHL cells through the elevation of cellular ceramide levels. The PCD is not associated with classic caspase pathway.


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos , Apoptosis , Línea Celular Tumoral , Linfoma no Hodgkin , Rituximab , Farmacología , Esfingosina , Farmacología
4.
Chinese Medical Journal ; (24): 2638-2645, 2015.
Artículo en Inglés | WPRIM | ID: wpr-315280

RESUMEN

<p><b>BACKGROUND</b>Pyroptosis is the term for caspase-1-dependent cell death associated with pro-inflammatory cytokines. The role of alveolar macrophage (AM) pyroptosis in the pathogenesis of the acute lung injury and acute respiratory distress syndrome (ALI/ARDS) remains unclear.</p><p><b>METHODS</b>C57BL/6 wild-type mice were assigned to sham, lipopolysaccharide (LPS) + vehicle, LPS + acetyl-tyrosyl-valyl- alanyl-aspartyl-chloromethylketone (Ac-YVAD-CMK) and LPS + Z-Asp-Glu-Val-Asp-fluoromethylketone groups. Mice were given intraperitoneal (IP) injections of LPS. Drugs were IP injected 1 h before LPS administration. Mice were sacrificed 16 h after LPS administration, and AMs were isolated. Western blot analysis for active caspase-1 and cleaved caspase-3, evaluation of lung injury and a cytokine release analysis were performed. AMs were treated with LPS and adenosine triphosphate (ATP); caspase-1-dependent cell death was evaluated using flow cytometry; the apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) pyroptosomes were examined by immunofluorescence.</p><p><b>RESULTS</b>The expression of activated caspase-1 in AMs was enhanced following LPS challenge compared with the sham group. In the ex vivo study, the caspase-1/propidium iodide-positive cells, caspase-1 specks and ASC pyroptosomes were up-regulated in AMs following LPS/ATP stimulation. The specific caspase-1 inhibitor Ac-YVAD-CMK inhibited the activation of caspase-1 and pyroptotic cell death. Ac-YVAD-CMK also reduced the lung injury, pulmonary edema and total protein in bronchoalveolar lavage fluid (BALF). In addition, Ac-YVAD-CMK significantly inhibited interleukin-α2 (IL-1α2) release both in serum and BALF and reduced the levels of IL-18, tumor necrosis factor-α± (TNF-α±), High Mobility Group Box 1 (HMGB1) in BALF during LPS-induced ALI/ARDS.</p><p><b>CONCLUSIONS</b>This study reported AM pyroptosis during LPS-induced ALI/ARDS in mice and has demonstrated that Ac-YVAD-CMK can prevent AM-induced pyroptosis and lung injury. These preliminary findings may form the basis for further studies to evaluate this pathway as a target for prevention or reduction of ALI/ARDS.</p>


Asunto(s)
Animales , Masculino , Ratones , Lesión Pulmonar Aguda , Clorometilcetonas de Aminoácidos , Farmacología , Lipopolisacáridos , Toxicidad , Macrófagos Alveolares , Ratones Endogámicos C57BL , Oligopéptidos , Farmacología , Piroptosis
6.
Acta Pharmaceutica Sinica ; (12): 1124-1129, 2014.
Artículo en Chino | WPRIM | ID: wpr-299158

RESUMEN

The present study is to elucidate the mechanisms underlying Gleevec-induced apoptosis of chronic myeloid leukemia (CML) K562 cells in vitro. The apoptotic cell death and cell cycle distribution after Gleevec treatment and the effect of PDCD4 siRNA on Gleevec-induced apoptosis of K562 cells were analyzed by flow cytometry. The effect of Gleevec on p-Crkl, caspase-3, PARP and PDCD4 protein levels, and the knockdown efficacy of PDCD4 siRNA were detected by Western blotting. The results showed that Gleevec dramatically suppressed the phosphorylation level of Crkl in a dose-dependent manner and induced significant apoptosis and G0/G1 cell cycle arrest of K562 cells in time- and dose-dependent manners. In addition, Gleevec activated caspase-3 and its downstream substrates PARP, and the caspase pan inhibitor Z-VAD-FMK (50 micromol x L(-1)) markedly reduced Gleevec-induced apoptosis from 47.97% +/- 10.56% to 31.05% +/- 9.206% (P < 0.05). Moreover, Gleevec significantly increased the protein expression of programmed cell death 4 (PDCD4). PDCD4 knockdown by siRNA reduced Gleevec-induced apoptosis from 46.97% +/- 14.32% to 42.8% +/- 11.43%. In summary, Gleevec induced apoptosis in K562 cells via caspase-3 activation.


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos , Apoptosis , Benzamidas , Farmacología , Caspasa 3 , Metabolismo , Ciclo Celular , Mesilato de Imatinib , Células K562 , Fosforilación , Piperazinas , Farmacología , Pirimidinas , Farmacología
7.
Korean Journal of Physical Anthropology ; : 105-114, 2013.
Artículo en Inglés | WPRIM | ID: wpr-213476

RESUMEN

Gambogic acid (GA) has powerful apoptotic actions. The authors investigated whether GA has apoptotic effects on aortic smooth muscle cells, and compared its potency with that of simvastatin. Smooth muscle cells were isolated from the aortas of Sprague-Dawley rats (4-6 week). Cell purities were confirmed by IF staining using alpha-smooth muscle actin antibody. The IC50 values for cell death by GA and simvastatin were determined using a MTT assay, and the apoptotic effects of 1 microM GA or 30 microM simvastatin (concentrations correspond to IC50 values) were determined after 24 h of treatment using live cell images and by FITC annexin-V and propidium iodide double-staining. In addition, western blotting was used to evaluate apoptosis by quantifying reductions in the expression levels of the PARP and procaspase-3 as well as cleavages of PARP and procaspase-3 after treatment with 1 microM GA or 30 microM simvastatin. The IC50 of GA (1 microM) was lower than that of simvastatin (30 microM). Cell numbers were markedly reduced by both drugs in live cell images. GA (1 microM) produced a higher level of apoptosis than 30 microM simvastatin (26.4+/-2.37% vs. 8.3+/-1.54%, respectively; P<0.05, n=3) by FITC annexin-V & PI double-staining. In addition, 1 microM GA reduced the expressions of PARP, procaspase-3, and Mcl-1 in cells, whereas 30 microM simvastatin did not. Pretreatment with z-VAD-fmk attenuated GA-induced apoptosis and the cleavages of PARP and procaspase-3. The decreased level of Mcl-1 protein induced by GA treatment was recovered by z-VAD-fmk. These results indicate that GA-induced apoptosis was mediated by a caspase-dependent pathway.


Asunto(s)
Actinas , Clorometilcetonas de Aminoácidos , Aorta , Apoptosis , Western Blotting , Caspasa 3 , Recuento de Células , Muerte Celular , Fluoresceína-5-Isotiocianato , Concentración 50 Inhibidora , Músculo Liso , Músculos , Miocitos del Músculo Liso , Propidio , Ratas Sprague-Dawley , Simvastatina , Xantonas
8.
Korean Journal of Blood Transfusion ; : 89-98, 2011.
Artículo en Coreano | WPRIM | ID: wpr-10525

RESUMEN

BACKGROUND: Cryopreservation of hematopoietic stem cells has become an important process due to the therapeutic protocol, which includes stem cell transplantation after chemotherapy, for many hematological malignancies. The conventional medium contains 10% dimethyl sulfoxide (DMSO) as a cryoprotectant, but this has been reported to be related with many complications. We analyzed the usefulness of trehalose, catalase and zVAD-fmk for cryopreservation along with using a reduced concentration of DMSO to 5%. METHODS: Peripheral blood stem cells were frozen in 10% DMSO as a control and also in 5% DMSO with trehalose and catalase. After 3 weeks of storage in a liquid nitrogen tank, the viability of the thawed hematopoietic stem cells was measured using Trypan blue staining and 7-AAD analysis via conducting flow cytometry. The colony forming potential was assessed using methylcellulose culture. We measured the viability of cells in 5% DMSO medium with or without addition of 30 uM zVAD-fmk right after thawing, and we also did this 6 and 24 hours after incubation. RESULTS: Cryopreserved cells in 5% DMSO with trehalose and catalase showed similar survival (50.42%) compared with the control (49.78%). The viability of cells that were also treated with added zVAD-fmk showed a better result (13.12%) than without it (5.5%) after 24 hours of incubation. Colony forming assay showed similar colony formation in 5% DMSO with the natural cryoprotectants. CONCLUSION: According to the results, lowering the DMSO concentration to 5% is significant and we can expect better cell viability and prevent many side effects of high dose DMSO when adding natural cryprotectants in the cryopreservation medium or by adding caspase-inhibitor right after thawing.


Asunto(s)
Clorometilcetonas de Aminoácidos , Catalasa , Supervivencia Celular , Criopreservación , Dimetilsulfóxido , Diminazeno , Citometría de Flujo , Neoplasias Hematológicas , Células Madre Hematopoyéticas , Metilcelulosa , Nitrógeno , Safrol , Trasplante de Células Madre , Células Madre , Trehalosa , Azul de Tripano
9.
Korean Journal of Medicine ; : 75-86, 2010.
Artículo en Coreano | WPRIM | ID: wpr-86572

RESUMEN

BACKGROUND/AIMS: Peroxisome proliferator-activated receptor (PPAR)-gamma ligand is known to inhibit the growth of several kinds of cancer cells, yet its effect on cholangiocarcinoma is indecisive. We investigated the effect of an endogenous ligand of PPAR-gamma, 15-deoxy-delta (12,14)-prostaglandin J2 (15-deoxy-PGJ2) on cholangiocarcinoma cells that were established from intrahepatic cholangiocarcinoma tissue of Korean patients. METHODS: Four cholangiocarcinoma cell lines, Cho-CK, Choi-CK, JCK and SCK, were studied. The mRNA expression of PPAR-gamma, bcl-2, and bax were examined by RT-PCR. Cell viability was determined by MTT assay. The cell cycle was analyzed by flow cytometry, and apoptosis by cell death detection ELISA kit. Caspase activity was measured by colorimetric assay. The effect of caspase inhibitors on 15-deoxy-PGJ2-induced apoptosis was determined by measuring cell viability using the MTT assay. RESULTS: PPAR-gamma mRNA was expressed in all cholangiocarcinoma cells. 15-deoxy-PGJ2 inhibited proliferation of all cells in a dose- and time-dependent manner. All cells treated with 15-deoxy-PGJ2 showed increased dose-dependent apoptosis. Caspase 3 was activated in all cells and caspase 9 was activated in all but JCK cells after 15-deoxy-PGJ2 treatment. Caspase 8 activity showed no significant change. The pan-caspase inhibitor, Z-VAD-FMK, and the caspase-3 inhibitor, Z-DEVD-FMK, blocked 15-deoxy-PGJ2-induced apoptosis in all cells dose-dependently. The expression of bcl-2 was decreased in Cho-CK, Choi-CK and SCK cells, and bax expression was not changed significantly after 15-deoxy-PGJ2 treatment. CONCLUSIONS: PPAR-gamma mRNA was expressed in all Korean cholangiocarcinoma cells. Our data suggest that 15-deoxy-PGJ2 exerts an antineoplastic effect against cholangiocarcinoma cells by inducing apoptosis through caspase activation.


Asunto(s)
Clorometilcetonas de Aminoácidos , Apoptosis , Caspasa 3 , Caspasa 8 , Caspasa 9 , Inhibidores de Caspasas , Ciclo Celular , Muerte Celular , Línea Celular , Supervivencia Celular , Colangiocarcinoma , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Neoplasias Hepáticas , Oligopéptidos , Peroxisomas , PPAR gamma , Prostaglandina D2 , ARN Mensajero
10.
The Korean Journal of Physiology and Pharmacology ; : 407-412, 2010.
Artículo en Inglés | WPRIM | ID: wpr-728352

RESUMEN

3-Deazaadenosine (DZA), a potent inhibitor of S-adenosylhomocysteine hydrolase, was previously proposed to induce intrinsic apoptosis in human leukemic cells. In the present study, we analyzed the mechanism underlying the DZA-induced intrinsic apoptotic pathway. DZA activated typical caspase-dependent apoptosis in HL-60 cells, as demonstrated by an accumulation of hypo-diploidic cells, the processing of multiple procaspases and an inhibitory effect of z-VAD-Fmk on this cell death. During DZA-induced apoptosis, cytochrome c (cyt c) was released into the cytosol. This was neither prevented by z-VAD-Fmk and nor was it associated with the dissipation of mitochondrial membrane potential (DeltaPsim). Prior to the release of cyt c, BAX was translocated from the cytosol to mitochondria and underwent oligomerization. Finally, the overexpression of BCL-XL protected HL-60 cells from apoptosis by blocking both the cyt c release and BAX oligomerization. Collectively, these findings suggest that DZA may activate intrinsic apoptosis by stimulating BAX activation and thereby the release of cyt c.


Asunto(s)
Humanos , Adenosilhomocisteinasa , Clorometilcetonas de Aminoácidos , Apoptosis , Proteína X Asociada a bcl-2 , Proteína bcl-X , Muerte Celular , Citocromos c , Citosol , Células HL-60 , Potencial de la Membrana Mitocondrial , Mitocondrias , Tubercidina
11.
Chinese Journal of Oncology ; (12): 173-178, 2010.
Artículo en Chino | WPRIM | ID: wpr-260442

RESUMEN

<p><b>OBJECTIVE</b>To investigate the involvement of apoptosis inducing factor (AIF) in caspase-independent pathway mediating apoptosis of cultured renal tubular epithelial cells induced by cisplatin (CP).</p><p><b>METHODS</b>Western Blot analysis and real-time PCR were performed to detect cytosol AIF (cAIF), nuclear AIF (nAIF) and AIF mRNA expression in cultured renal epithelial cells (HK-2) treated with cisplatin (CP) at various concentrations (0 - 200 micromol/L) and time courses (0 - 12 h). Immunofluorescence analysis was used to detect the AIF protein distribution in HK-2 cells. Pan-caspase inhibitor (Z-VAD-FMK) and AIF-siRNA treatment, TUNEL and flow cytometer were used to measure the suppression of apoptosis induced by CP in HK-2 cells.</p><p><b>RESULTS</b>The expressions of cAIF, nAIF protein and AIF mRNA were all increased to some extent in HK-2 cells treated with CP at various concentrations and time points. cAIF expression was 2.3-fold (P < 0.05) increased after 25 micromol/L CP treatment for 12 h and 1.7-fold (P < 0.01) increased after 50 micromol/L CP treatment for 3 h, compared with that of control groups, and showed a concentration- and time-dependent increment. The nAIF expression reached a peak (4.3-fold increase) (P < 0.005) after 150 micromol/L CP treatment for 12 h and 3.7-fold incease (P < 0.05) after 50 micromol/L CP treatment for 9 h, compared with that of the 25 micromol/L group and 3 h group, respectively. The expression of nAIF was approximately consistent with cleaved-PARP expressive pattern. Real-time PCR showed that AIF mRNA increased gradually with prolonged treatment with 50 micromol/L CP and reached a peak at 9 h. Immunofluorescence assay showed AIF translocation from cytosol to nuclei in some cultured HK-2 cells treated with CP. Applying pan-caspase inhibitor (Z-VAD-FMK) and AIF-siRNA to CP-treated HK-2 cells, the apoptotic rates were decreased by 60.1% and 39.2%, respectively. The inhibitory effect on HK-2 cell apoptosis was even more significant with combination of both Z-VAD-FMK and AIF-siRNA.</p><p><b>CONCLUSION</b>The AIF activation and translocation to nuclei with the increment of its mRNA expression mediates CP-induced apoptosis of renal tubular epithelial cells in vitro. It may provide a new therapeutic target for protecting from nephrotoxciity of cisplatin.</p>


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos , Farmacología , Antineoplásicos , Farmacología , Apoptosis , Factor Inductor de la Apoptosis , Genética , Metabolismo , Inhibidores de Caspasas , Núcleo Celular , Metabolismo , Células Cultivadas , Cisplatino , Farmacología , Citosol , Metabolismo , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Células Epiteliales , Biología Celular , Metabolismo , Túbulos Renales , Biología Celular , Transporte de Proteínas , Interferencia de ARN , ARN Mensajero , Metabolismo , ARN Interferente Pequeño , Genética
12.
An. acad. bras. ciênc ; 80(1): 129-136, Mar. 2008. graf
Artículo en Inglés | LILACS | ID: lil-477420

RESUMEN

Following infection with Leishmania major, T cell activation and apoptosis can be detected in draining lymph nodes of C57BL/6-infected mice. We investigated the mechanisms involved in apoptosis and cytokine expression following Tcellactivation. After two weeks of infection, apoptotic T cells were not detected in draining lymph nodes but activation with anti-CD3 induced apoptosis in both CD4 and CD8 T cells. Treatment with anti-FasLigand, caspase-8 or caspase- 9 inhibitors did not block activation-induced T-cell death. We also investigated whether the blockade of caspase-8 activity would affect the expression of type-1 or type-2 cytokines. At early stages of infection, both CD4 and CD8 T cells expressed IFN-gamma upon activation. Treatment with the caspase-8 inhibitor zIETD-fmk (benzyl-oxycarbonyl-Ile- Glu(OMe)-Thr-Asp(OMe)-fluoromethyl ketone) reduced the proportion of CD8 T cells and IFN-gamma expression in both CD4 and CD8T cells. We conclude that a non apoptotic role of caspase-8 activity may be required for T cell-mediated type-1 responses during L. major infection.


A ativação e a morte por apoptose de linfócitos T foram observadas em linfonodos drenantes de camundongos C57BL/6 infectados com Leishmania major. Investigamos os mecanismos envolvidos na apoptose e na expressão de citocinas após a ativação de linfócitos T. Após duas semanas de infecção, embora as células apoptóticas ainda não sejam detectadas em linfonodos drenantes, células T CD4 e CD8 sofrem apoptose após ativação com anti-CD3. O tratamento com anticorpo antagonista anti-Ligante de Fas, ou com inibidores das caspases-8 e 9, não bloqueou a morte induzida por ativação das células T. Investigamos também se a inibição da atividade da caspase-8 poderia afetar a expressão de citocinas tipo-1 ou tipo-2. Nos estágios iniciais da infecção, células T CD4 e CD8 de animais infectados com L. major expressaram IFN-gama após ativação. O tratamento com o inibidor de caspase-8 zIETD (benzoil-oxicarbonil-Ile-Glu(OMe)-Thr-Asp(OMe)-fluorometilcetona) durante a estimulação de células T reduziu a proporção de células T CD8 e a expressão de IFN-gama por células T CD4 e CD8. Concluimos que a atividade não apoptótica de caspase-8 pode ser necessária para o estabelecimento da imunidade mediada por células T durante a infecção por L. major.


Asunto(s)
Animales , Femenino , Ratones , Apoptosis/inmunología , /inmunología , /inmunología , /antagonistas & inhibidores , Interferón gamma/inmunología , Leishmania major/inmunología , Leishmaniasis Cutánea/inmunología , Clorometilcetonas de Aminoácidos/farmacología , /enzimología , /enzimología , Inhibidores de Cisteína Proteinasa/farmacología , Inmunidad Celular , Leishmaniasis Cutánea/parasitología , Ganglios Linfáticos/parasitología
13.
The Korean Journal of Laboratory Medicine ; : 430-437, 2008.
Artículo en Inglés | WPRIM | ID: wpr-97400

RESUMEN

BACKGROUND: Human telomerase reverse transcriptase (hTERT) is a catalytic enzyme that is required for telomerase activity (TA) and cancer progression. Telomerase inhibition or inactivation increases cellular sensitivity to UV irradiation, DNA-damaging agents, the tyrosine kinase inhibitor, imatinib, and pharmacological inhibitors, such as BIBR1532. hTERT is associated with apoptosis. Some patients show drug-resistance during anti-cancer drug treatment and the cancer cell acquire anti-apoptotic mechanism. Therefore, we attempted to study correlation between hTERT and drug-resistance. METHODS: To study the correlation between protein level and activity of hTERT and drug-resistance, Western blotting and telomerase repeat amplification protocol (TRAP) assays were performed. To investigate whether hTERT contributes to drug resistance in tumor cells, we transiently decreased hTERT levels using small interfering RNA (siRNA) in T24/R2 cells. RESULTS: hTERT knockdown increased Bax translocation into the mitochondria and cytochrome C release into the cytosol. Caspase inhibitors, especially Z-VAD-FMK, rescued this phenomenon, suggesting that the stability or expression of hTERT might be regulated by caspase activity. CONCLUSIONS: These data suggest that hTERT might be a target molecule for drug-resistant tumor therapy.


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos/farmacología , Antineoplásicos/farmacología , Caspasas/antagonistas & inhibidores , Línea Celular Tumoral , Cisplatino/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Grupo Citocromo c/metabolismo , Resistencia a Antineoplásicos/genética , Neoplasias/terapia , ARN Interferente Pequeño , Telomerasa/antagonistas & inhibidores , Proteína X Asociada a bcl-2/metabolismo
14.
Acta Physiologica Sinica ; (6): 715-722, 2008.
Artículo en Inglés | WPRIM | ID: wpr-302499

RESUMEN

To test the hypothesis that exogenous purified angiotensin II (ANG) might cause apoptosis of alveolar epithelial cells (AECs) and acute lung injury, male Wistar rats were intratracheally instilled with purified ANG (10 mumol/L), ANG plus the caspase inhibitor ZVAD-fmk (60 mumol/L), ANG plus the ANG receptor AT1 antagonist losartan (LOS, 100 mumol/L) or sterile phosphate-buffered saline (PBS) vehicle alone. Six or 20 h later, the lungs were lavaged in situ for determination of bronchoalveolar lavage (BAL) fluid content of hemoglobin (Hb) and fluorescent (BODIPY)-albumin, a bolus of which was injected intravenously 15 min prior to BAL. Terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) revealed that instillation of ANG, but not PBS alone, increased labeling of fragmented DNA in bronchiolar epithelial cells and in AECs (P<0.05) at 6 h post-ANG. Increased TUNEL was abrogated by concurrent instillation of ZVAD-fmk or LOS. Significant increased numbers of caspase-positive cells were observed by anti-caspase 3 immunolabeling after instillation of ANG (P<0.01); the same doses of LOS or ZVAD-fmk that blocked TUNEL also blocked the activation of caspase 3 (P<0.01). Intratracheal instillation of ANG also remarkably increased BAL BODIPY-albumin (P< 0.01) and Hb (P<0.05), both of which were eliminated by ZVAD-fmk or LOS. These data indicate that exposure of AECs to ANG in vivo is sufficient to induce apoptosis and alveolar epithelial barrier injury mediated by ANG receptor AT1.


Asunto(s)
Animales , Masculino , Ratas , Clorometilcetonas de Aminoácidos , Farmacología , Angiotensina II , Bloqueadores del Receptor Tipo 1 de Angiotensina II , Farmacología , Apoptosis , Caspasa 3 , Metabolismo , Inhibidores de Caspasas , Farmacología , Células Epiteliales , Patología , Losartán , Farmacología , Lesión Pulmonar , Patología , Ratas Wistar , Receptor de Angiotensina Tipo 1 , Metabolismo
15.
Acta Pharmaceutica Sinica ; (12): 132-138, 2007.
Artículo en Chino | WPRIM | ID: wpr-281954

RESUMEN

Although enediyne antibiotic lidamycin ( LDM) is a potent inducer of apoptosis, the underlying mechanisms of its apoptotic functions remain to be explored. Here, we aim to elucidate its possible mechanisms in mitochondria initiated apoptotic pathway involved in human BEL-7402 and MCF-7 cells. Cytochrome c released from mitchondria to cytosol fraction was detected by Western blotting. p53 and Bax, Bcl-2 expressions were detected by Western blotting and RT-PCR. MTT assay was used to detect cytotoxicity of LDM with or without caspase inhibitor z-VAD-fmk. After the BEL-7402 cells were exposed to 0. 1 micromol x L(-1) LDM within 6 h, the increase of cytochrome c in the cytosol and decrease in the mitochondria were observed when compared with untreated cells. The expression of Bax, an important proapoptotic member of the Bcl-2 family, increased gradually in the BEL-7402 cells after exposure to LDM of 0. 1 micromol x L (-1) for 2, 6, and 9 h, separately, while Bcl-2 increased at 2 and 6 h, and decreased at 9 h after LDM treatment. Enhanced protein expressions were parallel with respective increased mRNA level for Bax only, but not p53. Caspase inhibitor may inhibit partially the killing effects induced by LDM. Therefore we conclude that the rapid activation of mitochondrial pathway induced by LDM in tumor cells might contribute to its highly potent cytotoxicities.


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos , Farmacología , Aminoglicósidos , Farmacología , Antibióticos Antineoplásicos , Farmacología , Apoptosis , Western Blotting , Inhibidores de Caspasas , Caspasas , Metabolismo , Línea Celular Tumoral , Citocromos c , Metabolismo , Citosol , Metabolismo , Enediinos , Farmacología , Potencial de la Membrana Mitocondrial , Mitocondrias , Metabolismo , Proteínas Proto-Oncogénicas c-bcl-2 , Genética , ARN Mensajero , Genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Proteína p53 Supresora de Tumor , Genética , Proteína X Asociada a bcl-2 , Genética
16.
Chinese Journal of Pathology ; (12): 384-389, 2007.
Artículo en Chino | WPRIM | ID: wpr-347779

RESUMEN

<p><b>OBJECTIVE</b>To study the molecular mechanism of TAp63gamma-induced cell apoptosis.</p><p><b>METHODS</b>Transcription and protein expression of apoptosis inducing factor and p63 were investigated by immunohistochemistry and RT-PCR in human esophageal squamous carcinoma cell line EC9706 respectively. Twenty-four hours after transfection with pcDNA3.1-TAp63gamma, the apoptosis and translocation of apoptosis inducing factor in EC9706 cells were studied by flow cytometry, laser confocal microscopy and mitochondrial/cytosol/nuclear extraction analysis respectively. Down-regulation of apoptosis inducing factor protein was achieved by RNAi and pretreatment with caspase inhibitor zVAD.fmk of EC9706 cells.</p><p><b>RESULTS</b>Presence of protein expressions of apoptosis inducing factor and absence of TAp63gamma was observed in the cytoplasm of untransfected cells. RT-PCR verified the subtype of p63 in EC9706 cells was DeltaNp63. After 24 hours of transfection, both nuclear and cytoplasmic expression of apoptosis inducing factor protein were observed in cells transfected with TAp63gamma and p53 expression vectors, but not in cells transfected with control vector. Cell apoptosis rates were 1.37%, 13.64%, 4.52%, 4.03% and 1.91% in the pcDNA3.1 transfection group, pcDNA3.1-TAp63gamma transfection group, apoptosis inducing factor siRNA and pcDNA3.1-TAp63gamma transfection group, zVAD.fmk treatment group, and the group receiving apoptosis inducing factor siRNA, plus zVAD.fmk treatment and pcDNA3.1-TAp63gamma transfection, respectively.</p><p><b>CONCLUSIONS</b>Apoptosis inducing factor of EC9706 cells is released from mitochondria into both the cytoplasm and nucleus during TAp63gamma induced apoptosis. Down-regulation of apoptosis inducing factor inhibits TAp63gamma-induced apoptosis. Overall, TAp63gamma-induced apoptosis is dependent on the expression of apoptosis inducing factor and caspase.</p>


Asunto(s)
Humanos , Clorometilcetonas de Aminoácidos , Farmacología , Apoptosis , Factor Inductor de la Apoptosis , Genética , Metabolismo , Carcinoma de Células Escamosas , Metabolismo , Patología , Inhibidores de Caspasas , Línea Celular Tumoral , Núcleo Celular , Metabolismo , Citoplasma , Metabolismo , Regulación hacia Abajo , Neoplasias Esofágicas , Metabolismo , Patología , Mitocondrias , Metabolismo , Plásmidos , Transporte de Proteínas , Interferencia de ARN , ARN Interferente Pequeño , Genética , Transactivadores , Genética , Metabolismo , Factores de Transcripción , Transfección , Proteínas Supresoras de Tumor , Genética , Metabolismo
17.
Experimental & Molecular Medicine ; : 634-642, 2006.
Artículo en Inglés | WPRIM | ID: wpr-106422

RESUMEN

In a preliminary study, we found that benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (zVAD- fmk), unlike Boc-aspartyl(OMe)-fluoromethylketone (BocD-fmk), at usual dosage could not prevent genistein-induced apoptosis of p815 mastocytoma cells. This study was undertaken to reveal the mechanism underlying the incapability of zVAD-fmk in preventing this type of apoptosis. We observed that 14-3-3 protein level was reduced in genistein-treated cells and that BocD-fmk but not zVAD-fmk prevented the reduction of 14-3-3 protein level and the release of Bad from 14-3-3. We also demonstrated that truncated Bad to Bcl-xL interaction in genistein- treated cells was prevented by BocD-fmk but not by zVAD-fmk treatment. Our data indicate that BocD- fmk, compared to zVAD-fmk, has a certain preference for inhibiting 14-3-3/Bad signalling pathway. We also elucidated that this differential efficacy of BocD-fmk and zVAD-fmk resulted from the different effect in inhibiting caspase-6 and that co-treatment of zVAD-fmk and caspase-6 specific inhibitor substantially prevented genistein-induced apoptosis. Our data shows that caspase-6 plays a role on Bad/14-3-3 pathway in genistein-induced apoptosis of p815 cells, and that the usual dose of zVAD-fmk, in contrast to BocD-fmk, did not prevent caspase-6 acting on 14-3-3/Bad-mediated event.


Asunto(s)
Ratones , Animales , Proteína Letal Asociada a bcl/metabolismo , Transducción de Señal/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mastocitoma , Hidrocarburos Fluorados/farmacología , Genisteína/farmacología , Inhibidores Enzimáticos/farmacología , Línea Celular Tumoral , Caspasa 6/antagonistas & inhibidores , Compuestos de Bencilo/farmacología , Apoptosis/efectos de los fármacos , Clorometilcetonas de Aminoácidos/farmacología , Proteínas 14-3-3/metabolismo
18.
Chinese Medical Sciences Journal ; (4): 107-110, 2006.
Artículo en Inglés | WPRIM | ID: wpr-243607

RESUMEN

<p><b>OBJECTIVE</b>To investigate the effect of interleukin-6 (IL-6) on the apoptosis of annulus fibrosus (AF) cell induced by interleukin-1beta (IL-1beta).</p><p><b>METHODS</b>Cultured AF cells were divided into 6 groups and treated with no drug, 10 ng/mL IL-6, 10 ng/mL IL-1beta, 10 ng/mL IL-1beta and Z-VAD-FMK (a caspase-9 inhibitor), 10 ng/mL IL-1beta and 10 ng/mL IL-6, 10 ng/mL IL-1beta and 100 ng/mL IL-6, respectively. After three days of culture, the apoptosis rate, the positive rates of caspase-3, -8, and -9 of AF cells were detected with flow cytometry.</p><p><b>RESULTS</b>The apoptosis rates of cells in group 1 to 6 were 2.67% +/- 1.08%, 2.71% +/- 0.53%, 20.37% +/- 1.57%, 11.34% +/- 0.67%, 18.17% +/- 0.74%, and 9.42% +/- 1.08%, respectively. There was no significant difference between group 1 and 2, while the apoptosis rates of group 4, 5, and 6 were significantly lower than group 3 (P = 0.001, P = 0.172, and P = 0.001, respectively). Positive rates of caspase-3 in group 5 (12.35% +/- 0.64%) and 6 (9.26% +/- 0.36%) were significantly lower than group 3 (17.14% +/- 0.72%; P = 0.001 and P < 0.001, respectively). And positive rates of caspase-9 in group 5 (15.13% +/- 1.45%) and 6 (10.17% +/- 2.50%) were significantly lower than group 3 (19.4% +/- 0.98% ; P = 0.014 and P = 0.004, respectively). But there was not obvious change of caspase-8 activity after IL-6 was added.</p><p><b>CONCLUSION</b>IL-6 is capable of protecting AF cells from IL-1beta induced apoptosis in vitro. Mechanism of the protection is related with the inhibition of caspase-3 and -9 activities.</p>


Asunto(s)
Animales , Conejos , Clorometilcetonas de Aminoácidos , Farmacología , Apoptosis , Inhibidores de Caspasas , Células Cultivadas , Inhibidores de Cisteína Proteinasa , Farmacología , Interleucina-1beta , Farmacología , Interleucina-6 , Farmacología , Disco Intervertebral , Biología Celular
19.
Indian J Exp Biol ; 2005 Jun; 43(6): 483-7
Artículo en Inglés | IMSEAR | ID: sea-63416

RESUMEN

The present study was designed to test the hypothesis that addition of anticaspase cocktails (inhibiting caspases and thus blocking apoptosis) to the extenders increases the post-thaw viability of equine spermatozoa. The addition of caspase inhibitors failed to improve the acrosome and plasma membrane integrity of spermatozoa, suggesting that in equine sperm cryopreservation protocols, the addition of these caspase inhibitors to cryopreservation medium may not be beneficial in protecting the sperm from the stress of cryopreservation.


Asunto(s)
Acrosoma/metabolismo , Reacción Acrosómica , Clorometilcetonas de Aminoácidos/farmacología , Animales , Anexina A5/farmacología , Caspasas/antagonistas & inhibidores , Membrana Celular/metabolismo , Supervivencia Celular , Criopreservación/métodos , Crioprotectores/farmacología , Fragmentación del ADN , Inhibidores Enzimáticos/farmacología , Citometría de Flujo , Congelación , Caballos , Masculino , Aglutinina de Mani/metabolismo , Propidio/farmacología , Preservación de Semen/métodos , Espermatozoides/metabolismo
20.
Rev. med. vet. (Bogota) ; (7): 83-93, mayo 2004. tab
Artículo en Español | LILACS | ID: lil-560465

RESUMEN

En este estudio se suplementaron cerdas con aminoácidos y vitaminas durante el último tercio de gestación y la lactancia para evaluar la respuesta sobre algunos parámetros reproductivos de la cerda. El estudio se realizó en una granja porcina localizada en el municipio de San Antonio del Tequendama con cerdas de la línea Dekalb. Se trabajó con dos grupos de animales cada uno compuesto por 30 cerdas seleccionadas y tratadas de la siguiente forma: Grupo experimental 1, al día 85 de gestación se le administró 3ml de Vitacalier vía intramuscular, al mismo tiempo que se le comenzó la administración de 5 gr diarios de Promocalier en el concentrado hasta el destete y 5ml de Robavit vía intramuscular al comienzo del parto; el grupo control 2, no recibió tratamiento. Se evaluaron los siguientes parámetros: a. Peso de la camada al nacimiento, b. Peso de la camada al destete, c. Nacidos muertos, d. Ganancia de pesos, e. Días de lactancia. En lo que respecta a los parámetros a, b, c, y d, no hubo diferencias significativas entre grupos; los resultados fueron: a. Con un peso de 1.52 y 1.40 Kg para los grupos 1 y 2 respectivamente; el parámetro b. Con valores de 5.97 Kg (grupo1) y (6.27 Kg (grupo2); el parámetro c. Nacidos muertos 1.83 lechones (grupo1) y 2.17 lechones (grupo 2); en lo que respecta al parámetro d. Los resultados obtenidos fueron de 0.2441 Kg (grupo 1) y 0.2399 Kg (grupo 2); a diferencia de los parámetros anteriores el parámetro e. reveló una diferencia significativa (p<0.05) entre grupos (18.6 días grupo 1 y 20.2 días grupo 2.) A diferencia del análisis estadístico el estudio representa ganancias económicas para el productor por el aumento de los kilogramos producidos y disminución de los días de lactancia, siendo rentable el uso de suplementos en granjas con estas características...


Asunto(s)
Animales , Avitaminosis , Clorometilcetonas de Aminoácidos , Embarazo , Mortinato , Peso al Nacer
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