Little information is available about the effects of exposure to pulsed microwaves on neuronal Ca^2＋ signaling under non-thermal conditions. In this study, rat pheochromocytoma （PC12） cells were exposed to pulsed m...Little information is available about the effects of exposure to pulsed microwaves on neuronal Ca^2＋ signaling under non-thermal conditions. In this study, rat pheochromocytoma （PC12） cells were exposed to pulsed microwaves for 6 min at a specific absorption rate （SAR） of 4 W/kg to assess possible real-time effects. During microwave exposure, free calcium dynamics in the cytosol, mitochondria, and nucleus of cells were monitored by time-lapse microfluorimetry using a genetically encoded calcium indicator （ratiometric-pericam, ratiometric-10ericam-mt,展开更多
AIM: To clarify whether Lysophosphatidic acid (LPA) activates the nuclear translocation of nuclear factor-κB (NF-κB) in pancreatic cancer. METHODS: Panc-1, a human pancreatic cancer cell line, was used throughout th...AIM: To clarify whether Lysophosphatidic acid (LPA) activates the nuclear translocation of nuclear factor-κB (NF-κB) in pancreatic cancer. METHODS: Panc-1, a human pancreatic cancer cell line, was used throughout the study. The expression of LPA receptors was confirmed by reverse-transcript polymerase chain reaction (RT-PCR). Cytosolic free calcium was measured by fluorescent calcium indicator fura-2, and the localization of NF-κB was visualized by immunofluorescent method with or without various agents, which effect cell signaling. RESULTS: Panc-1 expressed LPA receptors, LPA1, LPA2 and LPA3. LPA caused the elevation of cytosolic free calcium dose-dependently. LPA also caused the nuclear translocation of NF-κB. Cytosolic free calcium was attenuated by pertussis toxin (PTX) and U73122, an inhibitor of phospholipase C. The translocation of NF-κB was similarly attenuated by PTX and U73122, but phorbol ester, an activator of protein kinase C, alone did not translocate NF-κB. Furthermore, the translocation of NF-κB was completely blocked by Ca2+ chelator BAPTA-AM. Thapsigargin, an endoplasmic- reticulum Ca2+-ATPase pump inhibitor, also promoted the translocation of NF-κB. Staurosporine, a proteinkinase C inhibitor, attenuated translocation of NF-κB induced by LPA. CONCLUSION: These findings suggest that protein kinase C is activated endogenously in Panc-1, and protein kinase C is essential for activating NF-κB with cytosolic calcium and that LPA induces the nuclear translocation of NF-κB in Panc-1 by mobilizing cytosolic free calcium.展开更多
The sulfonate derivate of chrysin coordinates with Ca2+ to form a novel tetra-nuclear calcium complex [{Ca(C15H8O7S)(H2O)(DMSO)}3{Ca(C15H8O7S)(DMSO)2}]·4DMSO. The struc- ture of the complex is characterized by IR...The sulfonate derivate of chrysin coordinates with Ca2+ to form a novel tetra-nuclear calcium complex [{Ca(C15H8O7S)(H2O)(DMSO)}3{Ca(C15H8O7S)(DMSO)2}]·4DMSO. The struc- ture of the complex is characterized by IR, H NMR and X-ray single-crystal diffraction analysis. 1 The results show that the complex crystallizes in triclinic, space group Pi, cell parameter a = 1.4725(6) nm, b = 1.6480(7) nm, c = 2.1006(8) nm, α = 83.928(7)o, β = 85.938(7)o, γ = 85.212(7)o, V = 5.041(3) nm3, Dc = 1.476 g/cm3, Z = 2, μ =0.568 nm?1, F(000) = 2324, R = 0.0778, wR = 0.1821. In the complex, four Ca2+ which are bridged by four 5-hydroxyanion-7-dihydro-xyfla- vone-6-sulfonate ligands with their carbonyl and 5-hydroxyanion group build an approximate square. The coordination number of Ca2+ is 7 and the coordinated atoms are all oxygen from the carbonyl, hydroxyl and suflo-group of 5-hydroxyanion-7-hydroxyflavone-6-sulfonate, H2O and DMSO. Four ligands locate on two sides of the square. Two of them on the same side are almost paralleled and aromatic p-p stacking exists between them. Ligands on the opposite side are nearly perpendicular to each other. Meanwhile, the solid of title compound has the photoluminescent phenomenon. The title compound emits green fluorescence (λem = 520 nm) when it is excited at the wavelength of 410 nm and its photoluminescent mechanism is dis- cussed.展开更多
Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathw...Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathways by targeting specific proteins to cellular sub-domains where the levels of intracellular freecalcium are kept low by the calcium ejection properties of PMCAs. According to this model, PMCAs have been shown to interact functionally with the calcium-sensitive proteins neuronal nitric oxide synthase, calmodulindependent serine protein kinase, calcineurin and endothelial nitric oxidase synthase. Transgenic animals with altered expression of PMCAs are being used to evaluate the physiological significance of these interactions. To date, PMCA interactions with calcium-dependent partner proteins have been demonstrated to play a crucial role in the pathophysiology of the cardiovascular system via regulation of the nitric oxide and calcineurin/nuclear factor of activated T cells pathways. This new evidence suggests that PMCAs play a more sophisticated role than the mere ejection of calcium from the cells, by acting as modulators of signaling transduction pathways.展开更多
基金supported by the National Natural Science Foundation of China[No.31400716 and No.61401497]
文摘Little information is available about the effects of exposure to pulsed microwaves on neuronal Ca^2＋ signaling under non-thermal conditions. In this study, rat pheochromocytoma （PC12） cells were exposed to pulsed microwaves for 6 min at a specific absorption rate （SAR） of 4 W/kg to assess possible real-time effects. During microwave exposure, free calcium dynamics in the cytosol, mitochondria, and nucleus of cells were monitored by time-lapse microfluorimetry using a genetically encoded calcium indicator （ratiometric-pericam, ratiometric-10ericam-mt,
基金The Research Committee of Intractable Pancreatic Diseases, provided by the Ministry of Health, Labour, and Welfare, Japan, No. 50253448
文摘AIM: To clarify whether Lysophosphatidic acid (LPA) activates the nuclear translocation of nuclear factor-κB (NF-κB) in pancreatic cancer. METHODS: Panc-1, a human pancreatic cancer cell line, was used throughout the study. The expression of LPA receptors was confirmed by reverse-transcript polymerase chain reaction (RT-PCR). Cytosolic free calcium was measured by fluorescent calcium indicator fura-2, and the localization of NF-κB was visualized by immunofluorescent method with or without various agents, which effect cell signaling. RESULTS: Panc-1 expressed LPA receptors, LPA1, LPA2 and LPA3. LPA caused the elevation of cytosolic free calcium dose-dependently. LPA also caused the nuclear translocation of NF-κB. Cytosolic free calcium was attenuated by pertussis toxin (PTX) and U73122, an inhibitor of phospholipase C. The translocation of NF-κB was similarly attenuated by PTX and U73122, but phorbol ester, an activator of protein kinase C, alone did not translocate NF-κB. Furthermore, the translocation of NF-κB was completely blocked by Ca2+ chelator BAPTA-AM. Thapsigargin, an endoplasmic- reticulum Ca2+-ATPase pump inhibitor, also promoted the translocation of NF-κB. Staurosporine, a proteinkinase C inhibitor, attenuated translocation of NF-κB induced by LPA. CONCLUSION: These findings suggest that protein kinase C is activated endogenously in Panc-1, and protein kinase C is essential for activating NF-κB with cytosolic calcium and that LPA induces the nuclear translocation of NF-κB in Panc-1 by mobilizing cytosolic free calcium.
基金This work was supported by the Natural Science Foundation of Shaanxi Province(Grant No.2001K11-G5).
文摘The sulfonate derivate of chrysin coordinates with Ca2+ to form a novel tetra-nuclear calcium complex [{Ca(C15H8O7S)(H2O)(DMSO)}3{Ca(C15H8O7S)(DMSO)2}]·4DMSO. The struc- ture of the complex is characterized by IR, H NMR and X-ray single-crystal diffraction analysis. 1 The results show that the complex crystallizes in triclinic, space group Pi, cell parameter a = 1.4725(6) nm, b = 1.6480(7) nm, c = 2.1006(8) nm, α = 83.928(7)o, β = 85.938(7)o, γ = 85.212(7)o, V = 5.041(3) nm3, Dc = 1.476 g/cm3, Z = 2, μ =0.568 nm?1, F(000) = 2324, R = 0.0778, wR = 0.1821. In the complex, four Ca2+ which are bridged by four 5-hydroxyanion-7-dihydro-xyfla- vone-6-sulfonate ligands with their carbonyl and 5-hydroxyanion group build an approximate square. The coordination number of Ca2+ is 7 and the coordinated atoms are all oxygen from the carbonyl, hydroxyl and suflo-group of 5-hydroxyanion-7-hydroxyflavone-6-sulfonate, H2O and DMSO. Four ligands locate on two sides of the square. Two of them on the same side are almost paralleled and aromatic p-p stacking exists between them. Ligands on the opposite side are nearly perpendicular to each other. Meanwhile, the solid of title compound has the photoluminescent phenomenon. The title compound emits green fluorescence (λem = 520 nm) when it is excited at the wavelength of 410 nm and its photoluminescent mechanism is dis- cussed.
基金Supported by The Breast Cancer Campaign and the Research Institute in Healthcare Sciences (Armesilla AL)The Wellcome Trust (Emerson M)
文摘Emerging evidence suggests that plasma membrane calcium ATPases (PMCAs) play a key role as regulators of calcium-triggered signal transduction pathways via interaction with partner proteins. PMCAs regulate these pathways by targeting specific proteins to cellular sub-domains where the levels of intracellular freecalcium are kept low by the calcium ejection properties of PMCAs. According to this model, PMCAs have been shown to interact functionally with the calcium-sensitive proteins neuronal nitric oxide synthase, calmodulindependent serine protein kinase, calcineurin and endothelial nitric oxidase synthase. Transgenic animals with altered expression of PMCAs are being used to evaluate the physiological significance of these interactions. To date, PMCA interactions with calcium-dependent partner proteins have been demonstrated to play a crucial role in the pathophysiology of the cardiovascular system via regulation of the nitric oxide and calcineurin/nuclear factor of activated T cells pathways. This new evidence suggests that PMCAs play a more sophisticated role than the mere ejection of calcium from the cells, by acting as modulators of signaling transduction pathways.
