• Clinical and Experimental Reproductive Medicine
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• v.32 no.4
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• pp.337-346
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• 2005

Objective: The oligosaccharide moieties of glycoproteins and proteoglycans have a vital function in blastocyst differentiation. Concanavalin (ConA), a lectin, is known to bind on the preimplantation embryos, especially on blastocyst. In this study, we investigated whether ConA can modulate the trophoblast development and about the regulating mediator. Also, we investigated whether expansion is enough for hatching procession of the mouse blastocyst. Method: Embryos were collected at 72 h post hCG injection and chemicals were treated after 24 h (96 hr post hCG injection). ConA or calcium ionophore A23187 were exposed to blastocyst and than analysis the developmental process for 48 hr. Intracellular free-$Ca^{2+}$ concentration in trophectoderm was measured with confocal laser microscope after exposing to ConA or calcium ionophore A23187. ConA-pretreated blastocyst exposed to the calcium ionophore A23187 and then analyzed the developmental process. Otherwise ouabain was treated to the blastocyst to block the $Na^+/K^+$-ATPase activity. Results: In contrast to the control blastocyst, the ConA-exposed blastocysts developed beyond the expansion stage with significantly high rate (90.4%) at 12 h post administration. ConA induced an increase the intracellular $Ca^{2+}$ concentration in trophectoderm. Calcium ionophore A23187 also stimulated expansion of blastocyst. Most of the control blastocysts developed to the hatching stage at 144 h post hCG injection. However, strongly 65% of the ConA-exposed embryos were arrested at expanded stage at same time point. The developmental progression rates to hatching stage of both ConA- and calcium ionophore A23187-expose blastocysts were significantly lower than that of the control. However ConA-pretreated embryos developed to the hatching stage like control embryos. Ouabain showed a tendency to delayed the progress to expansion stage but did not inhibit the development to the hatching stage. Conclusion: ConA-mediated expansion is the result of the increase of intracellular free-calcium in blastocyst stage embryo. It is suspected that expansion of the blasocyst is a essential indirect factor in hatching and the calcium may triggering the cellular mechanisms for the both expansion and hatching progression.

• Journal of Ginseng Research
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• v.22 no.2
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• pp.126-132
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• 1998

In the present study, we examined effects of ginseng saponins (ginsenosides) on pp60c-src protein tyrosine kinase (PTK) activity, intracellular calcium concentration ([$Ca^{2+}$]i), and cell proliferation in NIH3T3 cells. Eight different ginsenosides [ginsenoside-Rb1 (G-$Rb_1$), -$Rb_2$, -Rc, -Rd, -Re, -Rf, -$Rg_1$, -$Rg_2$) and ginseng total saponin (GTS) were used for these experiments. All ginsenosides and GTS tested stimulated the activation of $pp60^{c-src}$ kinase, and especially G-$Rb_1$,-Rd,-$Rg_1$, and -$Rg_1$ showed a higher stimulatory effect than others at 16.7 $\mu\textrm{g}$/ml of ginsenosides with a 18 hr-incubation, increasing the activity by 4.5, 3.5, 3.5, and 3.0-fold, respectively, over that of untreated control. In addition, both G-Rd and -$Rg_2$)Rg2 increased ($Ca^{2+}$), to 202 and 334 nM, respectively, about 2-3-fold above the basal level within 7min at 250 $\mu\textrm{g}$/yml of ginsenosides. The increases of ($Ca^{2+}$), were eliminated by Pretreatment of EGTA, an extracellular calcium chelator, suggtasting that they result from an influx of calcium ion from extracellular medium rather than an efflux from intracellular calcium store, endoplasmic reticulum (ER). All ginsenosides studied enhanced cell proliferation to 1.2-1.4-fold over that of untreated control at 5~250 $\mu\textrm{g}$/ml of concentrations. Interestingly the promotion of cell proliferation by ginsenosides corresponded with the activation of c-src kinase, which is an early step in the mitogenic signaling cascade. Taken together, we suggest that some ginsenosides may lead to cellProliferation via the activation of cellular signal transduction Pathway involving $pp60^{c-src}$ kinase.

• KSBB Journal
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• v.27 no.5
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• pp.313-318
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• 2012

Dimethyl sulfoxide (DMSO) increased the intracellular calcium ion concentration in stably transfected Drosophila melanogaster S2 cells expressing recombinant cyclooxygenase 1 (COX-1). DMSO did not increase the Drosophila NOS (dNOS) transcript level in calcium chelator-treated cells. Expression of recombinant COX-1 due to DMSO was diminished in cells treated with calcium chelators or channel blockers. Our results indicate that an increased intracellular calcium ion concentration due to DMSO is associated with up-regulation of the dNOS gene, leading to enhanced expression of COX-1.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.1
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• pp.51-57
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• 2015

The etiology of periodontal disease is multifactorial. Exogenous stimuli such as bacterial pathogens can interact with toll-like receptors to activate intracellular calcium signaling in gingival epithelium and other tissues. The triggering of calcium signaling induces the secretion of pro-inflammatory cytokines such as interleukin-8 as part of the inflammatory response; however, the exact mechanism of calcium signaling induced by bacterial toxins when gingival epithelial cells are exposed to pathogens is unclear. Here, we investigate calcium signaling induced by bacteria and expression of inflammatory cytokines in human gingival epithelial cells. We found that peptidoglycan, a constituent of grampositive bacteria and an agonist of toll-like receptor 2, increases intracellular calcium in a concentration-dependent manner. Peptidoglycan-induced calcium signaling was abolished by treatment with blockers of phospholipase C (U73122), inositol 1,4,5-trisphosphate receptors, indicating the release of calcium from intracellular calcium stores. Peptidoglycan-mediated interleukin-8 expression was blocked by U73122 and 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis (acetoxymethyl ester). Moreover, interleukin-8 expression was induced by thapsigargin, a selective inhibitor of the sarco/endoplasmic reticulum calcium ATPase, when thapsigargin was treated alone or co-treated with peptidoglycan. These results suggest that the gram-positive bacterial toxin peptidoglycan induces calcium signaling via the phospholipase C/inositol 1,4,5-trisphosphate pathway, and that increased interleukin-8 expression is mediated by intracellular calcium levels in human gingival epithelial cells.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.433-441
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• 2006

Polyamines are essential for the normal cell growth and differentiation. They are also known to have paradoxical dual effects on cell proliferation. In this paper we show that the excess amount of polyamines induces apoptosis through the modulation of calcium signaling in LNCaP human prostate cancer cells. Polyamines, particularly spermidine and spermine, stimulated cell proliferation at a lower concentration (under 10 ${\mu}M$), but it inhibited cell viability at a higher concentration (40 ${\mu}M$). The levels of intracellular $Ca^{2+}$ concentration were increased only at a high concentration of polyamines treatment without any noticeable changes at lower concentrations. Nifedipine did not alter the increase of polyamine-induced $Ca^{2+}$ levels, but flufenamic acid totally abolished the increase of intracellular $Ca^{2+}$ levels. These results mean that polyamines induce $Ca^{2+}$ influx from the surroundings through nonselective cation channels on the cell membrane. The expression of Bcl-2 protein was almost completely blocked, but the level of Bax protein was increased dramatically in the cells treated with high concentration of polyamine. The present study shows that polyamines at a high concentration induce apoptosis through the modulation of intracellular calcium signaling. The increase of intracellular calcium level induced by polyamines, was possibly a result from the extracellular calcium influx through the nonselective cation channels.

• Biomolecules & Therapeutics
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• v.16 no.1
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• pp.21-27
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• 2008

Clotrimazole (CLT), a potent antifungal drug, is known to inhibit tumor cell proliferation. In the present study, we examined the role of intracellular $Ca^{2+}$ in CLT-induced cell cycle arrest of colon adenocarcinoma HT29 cells. CLT inhibited growth of HT29 cells in a concentration-dependent manner, which was associated with inhibition of cell cycle progression at the G(1)-S phase transition and an increase in the expression of cell cycle inhibitor proteins p27 and p53. CLT also suppressed the $Ca^{2+}$ overload by A23187, a calcium ionophore, suggesting its role in modulation of intracellular $Ca^{2+}$ concentration in HT29 cells. The simultaneous application of CLT and A23187 with addition of $CaCl_2$ (1mM) to the medium significantly reversed CLT-induced p27 and p53 protein level increase and growth suppression. Our results suggest that CLT induces cell cycle arrest of colon adenocarcinoma HT29 cells via induction of p27 and p53, which may, at least in part, be mediated by alteration of intracellular $Ca^{2+}$ level.

• Toxicological Research
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• v.11 no.2
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• pp.199-203
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• 1995

The focus of this study was to investigate that cellular parameters and glucose uptake might be altered by extracellular calcium and starvation. Addition of 1 mM $Ca^{++}$ to hepatocytes (equalling to the free calcium concentration of blood) significantly increased intracellular $Na^+$ and decreased $Na^+$ & LDH leakage. This pertains to the hepatocytes of control rats as well as those of rats fasted for 24 and 48. hr. These effects might be come from the membrane-stabilizing effects of calcium. But calcium had no effects on cell volumes, superoxide-formation and glucose uptake. Actually hepatocytes of starved rats showed changes in several cellular parameters. Starvation increased LDH leakage, glucose uptake and the total concentration of $Na^+$ and $Na^+$ whereas it markedly decreased cell volumes. Since total tonicity remained unchanged, intracellular $Na^+$ and $Na^+$ could contribute to a higher share of total osmolarity in starvation. Starvation increased the cytoplasmic pH because $R-NH^{3+}$ions and their corresponding counterions disappeared. This increase may be related to suppress the protonization of amino groups in proteins. Starvation decreased hepatic glycogen, a major compound that affects cytosolic volume of hepatocytes. The data indicate that starvation increases the glucose transport activity. The possible molecular basis will be discussed.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.774-778
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• 1998

Brazilin [7,11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10(6H)-tetrol] inhibited thrombin-, collagen- and ADP-induced aggregation of washed rat platelets. T hrombin- and collagen-induced ATP release were also inhibited by brazilin in a concentration-dependent manner. Brazilin inhibited the formation of platelet thromboxane $A_2$ caused by thrombin, whereas it had no effect on the prostaglandin $D_2$ formation. Brazilin inhibited $^3H$-arachidonic acid liberation from membrane phospholipids of thrombin-stimulated platelets. Brazilin inhibited the rise of intracellular free calcium caused by thrombin. These results indicate that the inhibition of phospholipase ($PLA_2$) activity and [$[Ca^{2+}]_1$ elevation might be at least a part of antiplatelet mechanism of brazilin.

• Journal of Pharmacopuncture
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• v.6 no.2
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• pp.149-158
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• 2003

Objective : The purpose of this study was to investigate the effect of Bee Venom on the lipopolysaccharide, sodium nitroprusside and hydrogen peroxide induced expression phospholipase $A_2$ and calcium concentration in RAW 264.7 cells, a murine macrophage cell line. Method : The expression of phospholipase $A_2$ was determined by western blotting with corresponding antibodies, and the generation of intracellular calcium concentration was investigated by delta scan system in RAW 264.7 cells. Results : 1. Compared with control, expressions of lipopolysaccharide-induced phospholipase $A_2$ were decreased significantly by $1\;{\mu}g/{\mu}l$ of bee venom and decreased by 0.5, $5\;{\mu}g/{\mu}l$ of bee venom. 2. Compared with control, expressions of sodium nitroprusside-induced phospholipase $A_2$ were decreased significantly by $5\;{\mu}g/{\mu}l$ of bee venom but increased by 0.5, $5\;{\mu}g/{\mu}l$ of bee venom. 3. Compared with control, expressions of hydrogen peroxide-induced phospholipase $A_2$ were decreased significaltly by $1{\mu}g/{\mu}l$ of bee venom and decreased by $0.5\;{\mu}g/{\mu}l$ of bee venom but increased by $5\;{\mu}g/{\mu}l$ of bee venom. 4. Compared with control, lipopolysaccharide, sodium nitroprusside and hydrogen peroxide- induced intracellular calcium concentrations were decreased by 0.5, 1, $5\;{\mu}g/{\mu}l$ of bee venom and by indomethacin

• Journal of Acupuncture Research
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• v.21 no.5
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• pp.179-190
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• 2004

Objectives : The purpose of this study was to investigate the effect of Bee Venom and Melittin acupuncture solution on the lipopolysaccharide and sodium nitroprusside- induced expression of cytosolic phospholipase $A_2$, tumor necrosis factor-${\alpha}$ and calcium concentration in RAW 264.7 cells, a murine macrophage cell line. Methods : The expression of cytosolic phospholipase $A_2$ and tumor necrosis factor-${\alpha}$ was determined by western blotting with corresponding antibodies, and the generation of intracellular calcium concentration was investigated by delta scan system in RAW 264.7 cells. Results : 1. Compared with control, expressions of lipopolysaccharide-induced cytosolic phospholipase $A_2$ were decreased significantly by $5{\mu}g/mL$ of bee venom and 5, $10{\mu}g/mL$ of melittin acupuncture solution and decreased by 0.5, $1{\mu}g/mL$ of bee venom. 2. Compared with control, expressions of sodium nitroprusside-induced phospholipase $A_2$ were decreased significantly by 0.5, 1, $5{\mu}g/mL$ of bee venom and by 5, $10{\mu}g/mL$ of melittin acupuncture solution. 3. Compared with control, expressions of lipopolysaccharide-induced tumor necrosis factor-${\alpha}$ were decreased significantly by $10{\mu}g/mL$ of melittin acupuncture solution and were not changed significantly by 0.5, 1, $5{\mu}g/mL$ of bee venom and $5{\mu}g/mL$ of melittin acupuncture solution. 4. Compared with control, expressions of sodium nitroprusside-induced tumor necrosis factor-${\alpha}$ were decreased significantly by 1, $5{\mu}g/mL$ of bee venom and 5, $10{\mu}g/mL$ of melittin acupuncture solution and decreased by $0.5{\mu}g/mL$ of bee venom 5. Compared with control, lipopolysaccharide-induced intracellular calcium concentrations were decreased by 0.5, 1, $5{\mu}g/mL$ of bee venom and $10{\mu}g/mL$ of melittin acupuncture solution and increased by $5{\mu}g/mL$ of melittin acupuncture solution. 6. Compared with control, sodium nitroprusside-induced intracellular calcium concentrations were decreased by 0.5, 1, $5{\mu}g/mL$ of bee venom and 5, $10{\mu}g/mL$ of melittin acupuncture solution.