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1.
Asian Journal of Andrology ; (6): 192-199, 2020.
Article Dans Anglais | WPRIM | ID: wpr-1009747

Résumé

The acrosome reaction is a prerequisite for fertilization, and its signaling pathway has been investigated for decades. Regardless of the type of inducers present, the acrosome reaction is ultimately mediated by the elevation of cytosolic calcium. Inositol 1,4,5-trisphosphate-gated calcium channels are important components of the acrosome reaction signaling pathway and have been confirmed by several researchers. In this study, we used a novel permeabilization tool BioPORTER® and first demonstrated its effectiveness in spermatozoa. The inositol 1,4,5-trisphosphate type-1 receptor antibody was introduced into spermatozoa by BioPORTER® and significantly reduced the calcium influx and acrosome reaction induced by progesterone, solubilized zona pellucida, and the calcium ionophore A23187. This finding indicates that the inositol 1,4,5-trisphosphate type-1 receptor antibody is a valid inositol 1,4,5-trisphosphate receptor inhibitor and provides evidence of inositol 1,4,5-trisphosphate-gated calcium channel involvement in the acrosome reaction in human spermatozoa. Moreover, we demonstrated that the transfer of 1,4,5-trisphosphate into spermatozoa induced acrosome reactions, which provides more reliable evidence for this process. In addition, by treating the spermatozoa with inositol 1,4,5-trisphosphate/BioPORTER® in the presence or absence of calcium in the culture medium, we showed that the opening of inositol 1,4,5-trisphosphate-gated calcium channels led to extracellular calcium influx. This particular extracellular calcium influx may be the major process of the final step of the acrosome reaction signaling pathway.


Sujets)
Humains , Mâle , Réaction acrosomique/physiologie , A-23187/pharmacologie , Calcium/pharmacologie , Ionophores calciques/pharmacologie , Systèmes de délivrance de médicaments , Récepteurs à l'inositol 1,4,5-triphosphate/métabolisme , Progestérone/pharmacologie , Spermatozoïdes/métabolisme , Zone pellucide/métabolisme
2.
Asian Journal of Andrology ; (6): 337-344, 2019.
Article Dans Anglais | WPRIM | ID: wpr-1009691

Résumé

To interact with the egg, the spermatozoon must undergo several biochemical and motility modifications in the female reproductive tract, collectively called capacitation. Only capacitated sperm can undergo acrosomal exocytosis, near or on the egg, a process that allows the sperm to penetrate and fertilize the egg. In the present study, we investigated the involvement of cyclic adenosine monophosphate (cAMP)-dependent processes on acrosomal exocytosis. Inhibition of protein kinase A (PKA) at the end of capacitation induced acrosomal exocytosis. This process is cAMP-dependent; however, the addition of relatively high concentration of the membrane-permeable 8-bromo-cAMP (8Br-cAMP, 0.1 mmol l-1) analog induced significant inhibition of the acrosomal exocytosis. The induction of acrosomal exocytosis by PKA inhibition was significantly inhibited by an exchange protein directly activated by cAMP (EPAC) ESI09 inhibitor. The EPAC selective substrate activated AE at relatively low concentrations (0.02-0.1 μmol l-1), whereas higher concentrations (>5 μmol l-1) were inhibitory to the AE induced by PKA inhibition. Inhibition of PKA revealed about 50% increase in intracellular cAMP levels, conditions under which EPAC can be activated to induce the AE. Induction of AE by activating the actin severing-protein, gelsolin, which causes F-actin dispersion, was inhibited by the EPAC inhibitor. The AE induced by PKA inhibition was mediated by phospholipase C activity but not by the Ca2+-channel, CatSper. Thus, inhibition of PKA at the end of the capacitation process induced EPAC/phospholipase C-dependent acrosomal exocytosis. EPAC mediates F-actin depolymerization and/or activation of effectors downstream to F-actin breakdown that lead to acrosomal exocytosis.


Sujets)
Humains , Mâle , 8-Bromo AMP cyclique/pharmacologie , Acrosome/métabolisme , Réaction acrosomique/effets des médicaments et des substances chimiques , A-23187/pharmacologie , AMP cyclique/métabolisme , Cyclic AMP-Dependent Protein Kinases/antagonistes et inhibiteurs , Exocytose/effets des médicaments et des substances chimiques , Facteurs d'échange de nucléotides guanyliques/métabolisme , Inhibiteurs de protéines kinases/pharmacologie , Transduction du signal/effets des médicaments et des substances chimiques , Spermatozoïdes/métabolisme , Thapsigargine/pharmacologie
3.
Natural Product Sciences ; : 1-4, 2017.
Article Dans Anglais | WPRIM | ID: wpr-198630

Résumé

Sinensetin, a pentamethoxyflavone, is known to exert various pharmacological activities including anti-angiogenesis, anti-diabetic and anti-inflammatory activities. However, its effects on the human mast cell - 1 (HMC-1) mediated inflammatory mechanism remain unknown. To explore the mediator and cellular inflammatory response of sinensetin, we examined its influence on phorbol 12-myristate 13-acetate (PMA) plus A23187 induced inflammatory mediator production in a human mast cell line. In this study, interleukin (IL)-6 production was measured using the enzyme-linked immunosorbent assay and reverse transcription polymerase chain reaction. Sinensetin inhibited PMA plus A23187 induced IL-6 production in a dose-dependent manner as well as IL-4, IL-5 and IL-8 mRNA expression. Furthermore, sinensetin inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation, suggesting that sinensetin inhibits the production of inflammatory mediators by blocking STAT3 phosphorylation. Moreover, sinensetin was found to inhibit nuclear factor kappa B activation. These findings suggest that sinensetin may be involved in the regulation of mast cell-mediated inflammatory responses.


Sujets)
Humains , A-23187 , Test ELISA , Interleukine-4 , Interleukine-5 , Interleukine-6 , Interleukine-8 , Interleukines , Mastocytes , Facteur de transcription NF-kappa B , Phosphorylation , Réaction de polymérisation en chaîne , Transcription inverse , ARN messager , Facteur de transcription STAT-3 , Transducteurs
4.
The Korean Journal of Physiology and Pharmacology ; : 213-220, 2016.
Article Dans Anglais | WPRIM | ID: wpr-728533

Résumé

Mast cells are primary mediators of allergic inflammation. Beta-1,3-glucan (BG) protects against infection and shock by activating immune cells. Activation of the BG receptor induces an increase in intracellular Ca2+, which may induce exocytosis. However, little is known about the precise mechanisms underlying BG activation of immune cells and the possible role of mitochondria in this process. The present study examined whether BG induced mast cell degranulation, and evaluated the role of calcium transients during mast cell activation. Our investigation focused on the role of the mitochondrial calcium uniporter (MCU) in BG-induced degranulation. Black mouse (C57) bone marrow-derived mast cells were stimulated with 0.5 microg/ml BG, 100 microg/ml peptidoglycan (PGN), or 10 microM A23187 (calcium ionophore), and dynamic changes in cytosolic and mitochondrial calcium and membrane potential were monitored. BG-induced mast cell degranulation occurred in a time-dependent manner, and was significantly reduced under calcium-free conditions. Ruthenium red, a mitochondrial Ca2+ uniporter blocker, significantly reduced mast cell degranulation induced by BG, PGN, and A23187. These results suggest that the mitochondrial Ca2+ uniporter has an important regulatory role in BG-induced mast cell degranulation.


Sujets)
Animaux , Souris , A-23187 , Calcium , Cytosol , Exocytose , Inflammation , Transport des ions , Mastocytes , Potentiels de membrane , Mitochondries , Peptidoglycane , Rouge de ruthénium , Choc
5.
National Journal of Andrology ; (12): 338-341, 2015.
Article Dans Chinois | WPRIM | ID: wpr-319497

Résumé

<p><b>OBJECTIVE</b>To investigate the pathogenesis of globozoospermia, fertilization ability of round-headed sperm, and the application value of assisted oocyte activation in intracytoplasmic sperm injection (ICSI) for the wives of glohozoospermia men.</p><p><b>METHODS</b>We collected oocytes from the wives of 2 globozoospermia patients and randomly divided them into two groups after ICSI to receive calcium ionophore A23187-activation and conventional treatment, respectively. We reviewed the relevant literature published at home and abroad, and discussed the etiology of globozoospermia, fertilization ability of round-headed sperm, and treatment options for this disease.</p><p><b>RESULTS</b>Quality embryos were obtained in the A23187-activation group while no fertilized oocytes, oocyte cleavage, quality embryos, or blastular formation were found in the conventional treatment group. Both women achieved pregnancy and gave birth to healthy neonates after transfer of the quality embryos from the A23187-activation group.</p><p><b>CONCLUSION</b>Calcium ionophore A23187 can be applied to ICSI for the wives of globozoospermia men and bring about desirable clinical outcomes. Meanwhile, attention should be paid to its safety.</p>


Sujets)
Femelle , Humains , Mâle , Grossesse , A-23187 , Utilisations thérapeutiques , Ionophores calciques , Utilisations thérapeutiques , Infertilité masculine , Traitement médicamenteux , Ovocytes , Injections intracytoplasmiques de spermatozoïdes , Spermatozoïdes , Malformations
6.
Chinese journal of integrative medicine ; (12): 380-386, 2013.
Article Dans Anglais | WPRIM | ID: wpr-293292

Résumé

<p><b>OBJECTIVE</b>Cheongseoikki-tang (CIT, Korean), also called Qingshu Yiqi decoction () and Seisho-ekki-to (Japanese), is well known as an effective traditional combination of herbs for treating cardiovascular diseases. This study was to research its effects on bone marrow-derived mast cell (BMMC)-mediated allergy and inflammation mechanisms.</p><p><b>METHODS</b>In this study, the biological effect of Cheongseoikki-tang ethanol extract (CITE) was evaluated, focusing on its effects on the production of allergic mediators by phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187)-stimulated BMMCs. These allergic mediators included interleukin-6 (IL-6), prostaglandin D2 (PGD2), leukotriene C4 (LTC4), and β-hexosaminidase (β-hex).</p><p><b>RESULTS</b>Our data revealed that CITE inhibited the production of IL-6, PGD2, LTC4, and β-hex induced by PMA plus A23187 (P<0.05).</p><p><b>CONCLUSION</b>These findings indicate that CITE has the potential for use in the treatment of allergy.</p>


Sujets)
Animaux , Mâle , Souris , Anti-inflammatoires , Pharmacologie , Utilisations thérapeutiques , Cellules de la moelle osseuse , Anatomopathologie , A-23187 , Pharmacologie , Dégranulation cellulaire , Survie cellulaire , Médicaments issus de plantes chinoises , Pharmacologie , Utilisations thérapeutiques , Hypersensibilité , Traitement médicamenteux , Anatomopathologie , Interleukine-6 , Sécrétions corporelles , Leucotriène C4 , Pharmacologie , Mastocytes , Anatomopathologie , Physiologie , Souris de lignée BALB C , Prostaglandine D2 , 12-Myristate-13-acétate de phorbol , Pharmacologie , beta-N-Acetylhexosaminidases , Métabolisme
7.
Immune Network ; : 55-62, 2013.
Article Dans Anglais | WPRIM | ID: wpr-147332

Résumé

Swiprosin-1 exhibits the highest expression in CD8+ T cells and immature B cells and has been proposed to play a role in lymphocyte biology through actin remodeling. However, regulation of swiprosin-1 gene expression is poorly understood. Here we report that swiprosin-1 is up-regulated in T cells by PKC pathway. Targeted inhibition of the specific protein kinase C (PKC) isotypes by siRNA revealed that PKC-theta is involved in the expression of swiprosin-1 in the human T cells. In contrast, down-regulation of swiprosin-1 by A23187 or ionomycin suggests that calcium-signaling plays a negative role. Interestingly, swiprosin-1 expression is only reduced by treatment with NF-kappaB inhibitors but not by NF-AT inhibitor, suggesting that the NF-kappaB pathway is critical for regulation of swiprosin-1 expression. Collectively, these results suggest that swiprosin-1 is a PKC-theta-inducible gene and that it may modulate the late phase of T cell activation after antigen challenge.


Sujets)
Humains , Actines , Biologie , A-23187 , Régulation négative , Expression des gènes , Ionomycine , Lymphocytes , Facteur de transcription NF-kappa B , Précurseurs lymphoïdes B , Protéine kinase C , Protein kinases , Petit ARN interférent , Lymphocytes T
8.
Chinese Journal of Applied Physiology ; (6): 559-564, 2013.
Article Dans Anglais | WPRIM | ID: wpr-235314

Résumé

<p><b>OBJECTIVE</b>To investigate the effects of endothelial microvesicles (EMVs) induced by calcium ionophore A23187 on H9c2 cardiomyocytes.</p><p><b>METHODS</b>Human umbilical vein endothelial cells (HUVECs) were treated with 10 micromol/L A23187 for 30 min. EMVs from HUVECs were isolated by ultracentrifugation from the conditioned culture medium. EMVs were characterized using 1 and 2 microm latex beads and anti-PE-CD144 antibody by flow cytometry. For functional research, EMVs at different concentrations were cocultured with H9c2 cardiomyocytes for 6 h. Cell viability of H9c2 cells and the activity of LDH leaked from H9c2 cells were tested by colorimetry. Moreover, apoptosis of H9c2 cells was observed through Hoechst 33258 staining and tested by FITC-Annexin V/PI double staining.</p><p><b>RESULTS</b>EMVs were induced by A23187 on HUVECs, and isolated by ultracentrifugation. We identified the membrane vesicles (< 1 microm) induced by A23187 were CD144 positive. In addition, the EMVs could significantly reduce the viability of H9c2 cells, and increase LDH leakage from H9c2 cells in a dose dependent manner (P < 0.05). Condensed nuclei could be observed with the increasing concentrations of EMVs through Hoechst 33258 staining. Furthermore, increased apoptosis rates of H9c2 cells could be assessed through FITC-Annexin V/PI double staining by flow cytometry.</p><p><b>CONCLUSION</b>Microvesicles could be released from HUVECs after induced by A23187 through calcium influx, and these EMVs exerted a pro-apoptotic effect on H9c2 cells by induction of apoptosis.</p>


Sujets)
Humains , Annexine A5 , Apoptose , A-23187 , Pharmacologie , Calcium , Métabolisme , Lignée cellulaire , Membrane cellulaire , Techniques de coculture , Cytométrie en flux , Fluorescéine-5-isothiocyanate , Cellules endothéliales de la veine ombilicale humaine , Myocytes cardiaques , Coloration et marquage
9.
Chinese Journal of Biotechnology ; (12): 986-997, 2013.
Article Dans Chinois | WPRIM | ID: wpr-233181

Résumé

We studied medium alkalinization in Salvia miltiorrhiza suspension cultures treated with salicylic acid and the effect of Ca2+ in this process through application of calcium channel antagonists (Verapamil, LaCl3, LiCl, 2-APB) and ionophore A23187. The results show that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture. Verapamil and LaCl3 or LiCl and 2-APB, two different groups of calcium channel antagonist, significantly inhibited the medium alkalinization induced by salicylic acid. However, the suppression effect of verapamil or LaCl3 on medium alkalinization induced by salicylic acid was higher than that of LiCl or 2-APB. When two types of calcium channel inhibitor (LaCl3 and 2-APB) were used together, the medium alkalinization induced by salicylic acid was completely suppressed and even reduced the pH in medium. On the other hand, A23187 could promote the medium alkalinization. Based on the results above, we speculated that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture, depending on the calcium from both extracell and intracell. Moreover, calcium from extracell plays a more dominant role in this process. Reveal of relationship in this research between Ca2+ and medium alkalinization can provide theory evidence for mechanism of the plant secondary metabolism.


Sujets)
A-23187 , Pharmacologie , Calcium , Chimie , Inhibiteurs des canaux calciques , Pharmacologie , Ionophores calciques , Pharmacologie , Techniques de culture cellulaire , Milieux de culture , Chimie , Acide salicylique , Pharmacologie , Salvia miltiorrhiza , Métabolisme , Vérapamil , Pharmacologie
10.
Biomolecules & Therapeutics ; : 435-441, 2013.
Article Dans Anglais | WPRIM | ID: wpr-202597

Résumé

Emodin, a naturally occurring anthraquinone derivative isolated from Polygoni cuspidati radix, has several beneficial pharmacologic effects, which include anti-cancer, anti-diabetic, and anti-inflammatory activities. In this study, the authors examined the effect of emodin on the production of proinflammatory cytokines, such as, tumor necrosis factor (TNF)-alpha and interleukin (IL)-6, in mouse bone marrow-derived mast cells (BMMCs) stimulated with phorbol 12-myristate 13-acetate (PMA) plus the calcium ionophore A23187. To investigate the mechanism responsible for the regulation of pro-inflammatory cytokine production by emodin, the authors assessed its effects on the activations of transcriptional factor nuclear factor-kappaB (NF-kappaB) and mitogen-activated protein kinases (MAPKs). Emodin attenuated the nuclear translocation of (NF)-kappaB p65 and its DNA-binding activity by reducing the phosphorylation and degradation of IkappaBalpha and the phosphorylation of IkappaB kinase B (IKK). Furthermore, emodin dose-dependently attenuated the phosphorylations of MAPKs, such as, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAP kinase, and the stress-activated protein kinases (SAPK)/c-Jun-N-terminal kinase (JNK). Taken together, the findings of this study suggest that the anti-inflammatory effects of emodin on PMA plus A23187-stimulated BMMCs are mediated via the inhibition of NF-kappaB activation and of the MAPK pathway.


Sujets)
Animaux , Souris , A-23187 , Calcium , Cytokines , Émodine , I-kappa B Kinase , Interleukine-6 , Interleukines , Mastocytes , Mitogen-Activated Protein Kinases , Facteur de transcription NF-kappa B , p38 Mitogen-Activated Protein Kinases , Phosphorylation , Phosphotransferases , Protein kinases , Facteur de nécrose tumorale alpha
11.
Journal of Central South University(Medical Sciences) ; (12): 1003-1007, 2012.
Article Dans Chinois | WPRIM | ID: wpr-814750

Résumé

OBJECTIVE@#To explore the effect of calcium ionophore (CI) A23187 plus IFN-γ on dendritic cells (DC) from healthy human peripheral blood mononuclear cells (PBMNC).@*METHODS@#PBMNC from healthy donors were treated with GM-CSF plus IL-4, A23187, and A23187 plus IFN-γ, respectively. After culture for 72 h, the change of cellular morphology was observed under light microscope and electron microscope. Surface markers on DC were analyzed by flow cytometry. MTT colorimetry was used to detect the proliferation of allogeneic T cells. Plasma concentrations of IL-12 and IFN-γ were measured by ELISA.@*RESULTS@#PBMNC treated with A23187 plus IFN-γ for 72 h presented DC with typical morphology effectively. The surface markers CD40, CD83, and CD86 were obviously increased in group A23187 plus IFN-γ (P<0.01), but decreased in CD1a (P<0.01). In addition, it evidently stimulated the proliferation of allogeneic T cells. The levels of IL-12 and IFN-γ were significantly increased compared with other groups (P<0.01).@*CONCLUSION@#A23187 plus IFN-γ can effectively enhance marked transformation of PBMNC into DC.


Sujets)
Humains , A-23187 , Pharmacologie , Ionophores calciques , Pharmacologie , Prolifération cellulaire , Cellules cultivées , Cellules dendritiques , Facteur de stimulation des colonies de granulocytes et de macrophages , Pharmacologie , Interféron gamma , Métabolisme , Pharmacologie , Interleukine-12 , Métabolisme , Interleukine-4 , Pharmacologie , Agranulocytes , Biologie cellulaire , Lymphocytes T , Biologie cellulaire
12.
Journal of Central South University(Medical Sciences) ; (12): 687-691, 2011.
Article Dans Chinois | WPRIM | ID: wpr-814532

Résumé

OBJECTIVE@#To investigate the relationship between sperm acrosome reaction (AR) and the clinical pregnancy rate of intrauterine insemination (IUI).@*METHODS@#We detected the sperm spontaneous AR rate and Ca2+ ionophore A23187-induced AR rate in 128 patients who accepted IUI treatment, collected their clinical data and analysed the relationship between sperm AR rate and clinical pregnancy rate of IUI.@*RESULTS@#There was no statistical difference between the spontaneous AR rates in the pregnant group and the non-pregnant group (7.7% vs. 7.0%, P>0.05), but there was statistical difference between the induced AR rates(51.9 % vs. 43.5%, P<0.05). There was statistical difference in the clinical pregnancy rate among the 3 IUI groups divided by induced AR rate (≤20.0%, 20.1%-49.9%, and ≥50.0%; 4.8% vs. 12.5% vs. 18.6%, P<0.05).@*CONCLUSION@#The spontaneous AR rate has nothing to do with the clinical pregnancy rate of IUI, but the induced AR rate is associated with the clinical pregnancy rate of IUI.


Sujets)
Adulte , Femelle , Humains , Mâle , Grossesse , Réaction acrosomique , Physiologie , A-23187 , Pharmacologie , Infertilité , Thérapeutique , Insémination artificielle avec conjoint , Méthodes , Taux de grossesse , Spermatozoïdes , Physiologie
13.
Experimental Neurobiology ; : 45-53, 2011.
Article Dans Anglais | WPRIM | ID: wpr-171918

Résumé

Cultured cortical primary astroglia treated with zinc died while rapidly detached from culture plates, a distinct part of zinc-treated astroglia. In the present study, we investigated the mechanism underlying the rapid change in the morphologic integrity of zinc-treated astroglia. Among the early cellular events occurring in zinc-treated astroglia, strong activation of p38 MAPK and JNK was evident. Although inhibitors of p38 (SB203580 and SB202190) or JNK (SP600125) did not protect zinc-insulted astroglia from cell death, the p38 inhibitors, but not the JNK inhibitor, suppressed actin filament and cell morphology disruption. The Ca2+ ionophore, A23187, also suppressed actin filament and cell morphology disruption, but not cell death, of zinc-insulted astroglia. However, A23187 did not inhibit p38 MAPK activation in zinc-treated astroglia. Together these results suggest that zinc influx in astroglia results in rapid loss of the morphologic integrity via mechanisms regulated by p38 kinase and/or Ca2+ signaling.


Sujets)
Cytosquelette d'actine , Astrocytes , A-23187 , Mort cellulaire , p38 Mitogen-Activated Protein Kinases , Phosphotransferases , Zinc
14.
Chinese Medical Journal ; (24): 3341-3346, 2011.
Article Dans Anglais | WPRIM | ID: wpr-319120

Résumé

<p><b>BACKGROUND</b>Glucose regulated protein 78 (GRP78), an endoplasmic reticulum (ER) chaperone, plays a critical role in chemotherapy resistance in a variety of cancers. In this study, we investigated the up-regulation of GRP78 induced by A23187 and its association with the chemotherapeutical sensibility to cisplatin in human lung cancer cell line SPCA1.</p><p><b>METHODS</b>SPCA1 cells were pretreated with A23187 at different concentrations. The expression of GRP78 at the mRNA level was analyzed by RT-PCR; the expression of GRP78 at the protein level was determined by Western blotting and immunofluorescence assay. Cell survival was determined by MTT assay. Cell apoptosis was analyzed by flow cytometry.</p><p><b>RESULTS</b>The expression of GRP78 at both the mRNA and protein levels was obviously induced by A23187 in SPCA1 cells, with an elevation of GRP78 by 2.1-fold at the mRNA level and by 3.8-fold at the protein level compared to the control. There was a dose-dependent response. Survival curve analysis demonstrated that A23187 induction caused a significant reduction of survival for the cells subjected to cisplatin treatment (P < 0.05). After treatment by cisplatin, the percentage of apoptotic cells in the A23187 pretreated group increased about three fold compared with the control group ((27.53 ± 4.32)% vs. (9.25 ± 3.64)%, P < 0.05).</p><p><b>CONCLUSIONS</b>A23187 treatment was fairly effective for the induction of GRP78 in SPCA1 cells at both the mRNA and protein levels. To a certain extent, GRP78 up-regulation by A23187 was associated with the enhancement of drug sensitivity to cisplatin in human lung cancer cell line SPCA1.</p>


Sujets)
Humains , Antinéoplasiques , Pharmacologie , Apoptose , Technique de Western , A-23187 , Pharmacologie , Lignée cellulaire tumorale , Cisplatine , Pharmacologie , Cytométrie en flux , Protéines du choc thermique , Génétique , Métabolisme , Tumeurs du poumon , Métabolisme , RT-PCR
15.
Chinese Journal of Lung Cancer ; (12): 38-41, 2010.
Article Dans Chinois | WPRIM | ID: wpr-294865

Résumé

<p><b>BACKGROUND AND OBJECTIVE</b>The expression levels of glucose-regulated protein 78 (GRP78) were elevated and correlated with resistance to chemotherapy drug VP-16 in lung cancer cells. However, little is known about the relationship between its expression and resistance to cisplatin in lung cancer cells. The aim of this study was to investigate the expression of GRP78 under the induction of A23187 and its significance in the resistance to anti-tumor drugs cisplatin in a human lung cancer SPCA-1 cell line.</p><p><b>METHODS</b>RT-PCR and Western blot were used to analyze the expression of GRP78 at mRNA and protein levels in SPCA-1 cell line induced byA23187 at different concentrations (0, 1, 2, 4, 6 microM). MTT was used to determine the effect of cisplation on cell survival.</p><p><b>RESULTS</b>The expressions of GRP78 at both mRNA and protein levels were increased obviously in SPCA-1 cell line induced by A23187, with a manner of dose-dependent of A23187 to a great degree; MTT assay showed that the cell survival rate of the A23187-induced group decreased significantly compare to the control group, also with a concentration-dependent manner of A23187.</p><p><b>CONCLUSION</b>The expression of GRP78 at both mRNA and protein levels were increased obviously in SPCA-1 cell line induced by A23187. The enhancement of GRP78 showed a negative correlation with the cell survival rate treated by cisplatin. All these indicated that overexpression of GRP78 can enhance the sensitivity to cisplatin and there is correlation between the expression of GRP78 and resistance to cisplatin of human lung cancer SPCA-1 cell line.</p>


Sujets)
Humains , Antinéoplasiques , Pharmacologie , Technique de Western , A-23187 , Pharmacologie , Lignée cellulaire tumorale , Survie cellulaire , Cisplatine , Pharmacologie , Résistance aux médicaments antinéoplasiques , Génétique , Physiologie , Protéines du choc thermique , Génétique , Métabolisme , RT-PCR
16.
Experimental & Molecular Medicine ; : 639-650, 2010.
Article Dans Anglais | WPRIM | ID: wpr-162253

Résumé

An abrupt increase of intracellular Ca2+ is observed in cells under hypoxic or oxidatively stressed conditions. The dysregulated increase of cytosolic Ca2+ triggers apoptotic cell death through mitochondrial swelling and activation of Ca2+-dependent enzymes. Transglutaminase 2 (TG2) is a Ca2+-dependent enzyme that catalyzes transamidation reaction producing cross-linked and polyaminated proteins. TG2 activity is known to be involved in the apoptotic process. However, the pro-apoptotic role of TG2 is still controversial. In this study, we investigate the role of TG2 in apoptosis induced by Ca2+-overload. Overexpression of TG2 inhibited the A23187-induced apoptosis through suppression of caspase-3 and -9 activities, cytochrome c release into cytosol, and mitochondria membrane depolarization. Conversely, down-regulation of TG2 caused the increases of cell death, caspase-3 activity and cytochrome c in cytosol in response to Ca2+-overload. Western blot analysis of Bcl-2 family proteins showed that TG2 reduced the expression level of Bax protein. Moreover, overexpression of Bax abrogated the anti-apoptotic effect of TG2, indicating that TG2-mediated suppression of Bax is responsible for inhibiting cell death under Ca2+-overloaded conditions. Our findings revealed a novel anti-apoptotic pathway involving TG2, and suggested the induction of TG2 as a novel strategy for promoting cell survival in diseases such as ischemia and neurodegeneration.


Sujets)
Humains , Apoptose , Protéines régulatrices de l'apoptose/métabolisme , A-23187/pharmacologie , Calcium/métabolisme , Caspases/métabolisme , Mort cellulaire , Survie cellulaire , Cytochromes c/métabolisme , Régulation négative , Protéines G/métabolisme , Cellules HEK293 , Cellules HeLa , Ionophores/pharmacologie , Mitochondries/métabolisme , Transglutaminases/métabolisme , Protéine Bax/génétique
17.
China Journal of Chinese Materia Medica ; (24): 2166-2170, 2010.
Article Dans Chinois | WPRIM | ID: wpr-262200

Résumé

<p><b>OBJECTIVE</b>To investigate the effect and mechanism of Huanglian Jiedu Tang active fraction (HIJDTAF) on calcium overloading in neurons.</p><p><b>METHOD</b>Cerebral ischemia was imitated by hypoxia/hypoglycemia damage on fetal rat neurons. Double wavelength fluorospectrophotometry was used to assay the content of calcium in neurons in order to evaluate the effect of HLJDTAF on calcium overloading. Neurons were treated with glutamic acid, potassium chloride (KCl), A23187, caffeine(CAF) and methacholine (Mch) to analysis the related mechanism of HLJDTAF on calcium overloading in neurons.</p><p><b>RESULT</b>HLJDTAF 0.3, 0.15 g x k(-1) could remarkably inhibit the calcium overloading in neurons caused by hypoxia/hypoglycemia, glutamic acid, KCl and A23187. HLJDTAF 0.3 g x kg(-1) could inhibit the increasing of calcium caused by CAF and Mch in the presence of and in the absence of extra-calcium.</p><p><b>CONCLUSION</b>HLJDTAF could remarkably inhibit the calcium overloading in neurons after cerebral ischemia injury, it probably plays the function via several pathways.</p>


Sujets)
Animaux , Mâle , Rats , Caféine , Pharmacologie , A-23187 , Pharmacologie , Calcium , Métabolisme , Cellules cultivées , Médicaments issus de plantes chinoises , Pharmacologie , Acide glutamique , Pharmacologie , Chlorure de méthacholine , Pharmacologie , Neurones , Biologie cellulaire , Métabolisme , Chlorure de potassium , Pharmacologie , Rat Sprague-Dawley , Spectrométrie de fluorescence
18.
Asian Journal of Andrology ; (6): 829-836, 2008.
Article Dans Anglais | WPRIM | ID: wpr-284737

Résumé

<p><b>AIM</b>To determine the cellular distribution of secretory phospholipase A(2) (sPLA(2)) in dependence on the acrosomal state and under the action of elastase released under inflammatory processes from leukocytes.</p><p><b>METHODS</b>Acrosome reaction of spermatozoa was triggered by calcimycin. Human leukocyte elastase was used to simulate inflammatory conditions. To visualize the distribution of sPLA(2) and to determine the acrosomal state, immunofluorescence techniques and lectin binding combined with confocal laser scanning fluorescence microscopy and flow cytometry were used.</p><p><b>RESULTS</b>Although sPLA(2) was detected at the acrosome and tail regions in intact spermatozoa, it disappeared from the head region after triggering the acrosome reaction. This release of sPLA(2) was associated with enhanced binding of annexin V-fluoroscein isothiocyanate (FITC) to spermatozoa surfaces, intercalation of ethidium-homodimer I, and binding of FITC-labelled concanavalin A at the acrosomal region. Spermatozoa from healthy subjects treated with elastase were characterized by release of sPLA(2), disturbance of acrosome structure, and loss of vitality.</p><p><b>CONCLUSION</b>The ability of spermatozoa to release secretory phospholipase A(2) is related to the acrosomal state. Premature destabilization of the acrosome and loss of sPLA(2) can occur during silent inflammations in the male genital tract. The distribution pattern of sPLA(2) in intact spermatozoa might be an additional parameter for evaluating sperm quality.</p>


Sujets)
Humains , Mâle , Acrosome , Physiologie , Réaction acrosomique , Annexine A5 , Métabolisme , Antibactériens , Pharmacologie , A-23187 , Pharmacologie , Éthidium , Cytométrie en flux , Colorants fluorescents , Techniques in vitro , Microscopie confocale , Pancreatic elastase , Métabolisme , Phosphatidylsérine , Métabolisme , Secretory Phospholipases A2 , Métabolisme , Sperme , Biologie cellulaire , Spermatozoïdes
19.
Experimental & Molecular Medicine ; : 574-582, 2007.
Article Dans Anglais | WPRIM | ID: wpr-82952

Résumé

Familial amyotrophic lateral sclerosis (fALS) is caused by mutations in Cu/Zn-superoxide dismutase (SOD1), and SOD1 aggregation and calcium toxicity are involved in neuronal death. However, the effect of altered calcium homeostasis on the SOD1 aggregation is unknown. To investigate whether calcium triggers mutant SOD1 aggregation in vitro, human mutant SOD1 (G93A) was transfected into motor neuronal cell line (VSC 4.1 cells). These cells were then treated with calcium ionophore A23187 or agents that induce intracellular calcium release like cyclic ADP ribose, ryanodine or thapsigargin. A23187 was found to increase mutant SOD1 aggregation and neuronal nitric oxide synthase (nNOS) expression. Moreover, the NOS inhibitor (L-NAME) and a NO-dependent cyclic GMP cascade inhibitor (ODQ) reduced SOD1 aggregation, whereas an exogenous NO donor (GSNO) increased mutant SOD1 aggregation, which was also prevented by NOS or cGMP cascade inhibitor. Our data demonstrate that calcium-influx increases SOD1 aggregation by upregulating NO in cultured motor neuronal cells.


Sujets)
Animaux , Humains , Rats , Sclérose latérale amyotrophique/génétique , A-23187/pharmacologie , Calcium/métabolisme , Calpain/métabolisme , Caspase-3/métabolisme , Lignée cellulaire , Ionophores/pharmacologie , Motoneurones/métabolisme , Complexes multiprotéiques , Mutation , Monoxyde d'azote/métabolisme , Protéines recombinantes/composition chimique , Superoxide dismutase/composition chimique , Transfection
20.
Korean Journal of Anatomy ; : 401-406, 2006.
Article Dans Anglais | WPRIM | ID: wpr-643795

Résumé

Heme oxygenage-1 (HO-1) is the rate-limiting enzyme in heme catabolism, which leads to the generation of carbon monoxide (CO), biliverdin, and free iron. HO-1 has been known to show strong immunosuppressive properties although its mechanisms are not completely understood. In this study, it was therefore investigated anti-inflammatory properties of HO-1 in HT-29 cell, human colonic epithelial cell line. CoPPIX, HO-1 inducer, induced HO-1 expression without NF-kappa B activation and significantly blocked the I kappa B-alpha degradation by TNF-alpha in HT-29. Inhibition of HO-1 activity by ZnPPIX reversed the suppressive effects of CoPPIX on I kappa B-alpha degradation by TNF-alpha. Calcium chelating agent BAPTA/AM and calcium channel blockers, Verapamil and Flunarizine suppressed I kappa B-alpha degradation by TNF-alpha in HT-29 cells like CoPPIX while calcium ionophore A23187 also dose-dependently reversed the suppressive effects of CoPPIX on I kappa B-alpha degradation by TNF-alpha like a ZnPPIX. Interestingly, treatment of ZnPPIX increased basal intracellular calcium in HT-29 cells. Collectively, these results suggest that HO-1 exerts anti-inflammatory effects by down-regulation of NF-kappa B activity via suppression of intracellular calcium during pathogenesis of colitis in colonic epithelium.


Sujets)
Humains , Biliverdine , A-23187 , Inhibiteurs des canaux calciques , Calcium , Monoxyde de carbone , Colite , Côlon , Régulation négative , Cellules épithéliales , Épithélium , Flunarizine , Hème , Cellules HT29 , Fer , Métabolisme , Facteur de transcription NF-kappa B , Facteur de nécrose tumorale alpha , Vérapamil
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