共查询到20条相似文献,搜索用时 15 毫秒
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Evelyn Jara María A. Hidalgo Juan L. Hancke Alejandra I. Hidalgo Sebastian Brauchi Luisa Nuñez Carlos Villalobos Rafael A. Burgos 《Cell biochemistry and biophysics》2014,68(3):497-509
Delphinidin is an anthocyanidin that possesses antioxidant and anti-inflammatory effects; however, some reports suggest that delphinidin has pro-inflammatory properties. For this reason, we assessed the effect of delphinidin on cytokine production in T cells. We demonstrated that delphinidin increased the cytosolic-free Ca2+ concentration by releasing Ca2+ from intracellular stores and increasing Ca2+ entry. The putative Ca2+ release activated Ca2+ (CRAC) channel inhibitors BTP2 and gadolinium reduced the calcium entry stimulated by the anthocyanidin. Delphinidin induced nuclear factor of activated T cells (NFAT) translocation and NFAT-Luc activity in Jurkat cells and was dependent on the CRAC channel and calcineurin pathway. Delphinidin increased the mRNA expression and production of IL-2 in Jurkat cells and was inhibited by BTP2 and cyclosporine A. Using peripheral blood lymphocytes, we demonstrated that delphinidin increased the production of IL-2 and IFN-γ and was inhibited by BTP2. Taken together, our results suggest that delphinidin exerts immunostimulatory effects on T cells by increasing cytokine production through CRAC channel and NFAT activation. 相似文献
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Chien‐Chen Lai Kai‐Zen Lu Man‐Tzu Chiu Tsung‐Han Hsieh Lei Wan Cheng‐Wen Lin 《Proteomics》2013,13(23-24):3442-3456
Japanese encephalitis virus (JEV) nonstructural protein 5 (NS5) exhibits a Type I interferon (IFN) antagonistic function. This study characterizes Type I IFN antagonism mechanism of NS5 protein, using proteomic approach. In human neuroblastoma cells, NS5 expression would suppress IFNβ‐induced responses, for example, expression of IFN‐stimulated genes PKR and OAS as well as STAT1 nuclear translocation and phosphorylation. Proteomic analysis showed JEV NS5 downregulating calreticulin, while upregulating cyclophilin A, HSP 60 and stress‐induced‐phosphoprotein 1. Gene silence of calreticulin raised intracellular Ca2+ levels while inhibiting nuclear translocalization of STAT1 and NFAT‐1 in response to IFNβ, thus, indicating calreticulin downregulation linked with Type I IFN antagonism of JEV NS5 via activation of Ca2+/calicineurin. Calcineurin inhibitor cyclosporin A attenuated NS5‐mediated inhibition of IFNβ‐induced responses, for example, IFN‐sensitive response element driven luciferase, STAT1‐dependent PKR mRNA expression, as well as phosphorylation and nuclear translocation of STAT1. Transfection with calcineurin (vs. control) siRNA enhanced nuclear translocalization of STAT1 and upregulated PKR expression in NS5‐expressing cells in response to IFNβ. Results prove Ca2+, calreticulin, and calcineurin involvement in STAT1‐mediated signaling as well as a key role of JEV NS5 in Type I IFN antagonism. This study offers insights into the molecular mechanism of Type I interferon antagonism by JEV NS5. 相似文献
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Kamaldeen A. Muili Dong Wang Abrahim I. Orabi Sheharyar Sarwar Yuhuan Luo Tanveer A. Javed John F. Eisses Syeda M. Mahmood Shunqian Jin Vijay P. Singh Meena Ananthanaravanan George Perides John A. Williams Jeffery D. Molkentin Sohail Z. Husain 《The Journal of biological chemistry》2013,288(1):570-580
Biliary pancreatitis is the leading cause of acute pancreatitis in both children and adults. A proposed mechanism is the reflux of bile into the pancreatic duct. Bile acid exposure causes pancreatic acinar cell injury through a sustained rise in cytosolic Ca2+. Thus, it would be clinically relevant to know the targets of this aberrant Ca2+ signal. We hypothesized that the Ca2+-activated phosphatase calcineurin is such a Ca2+ target. To examine calcineurin activation, we infected primary acinar cells from mice with an adenovirus expressing the promoter for a downstream calcineurin effector, nuclear factor of activated T-cells (NFAT). The bile acid taurolithocholic acid-3-sulfate (TLCS) was primarily used to examine bile acid responses. TLCS caused calcineurin activation only at concentrations that cause acinar cell injury. The activation of calcineurin by TLCS was abolished by chelating intracellular Ca2+. Pretreatment with 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid (acetoxymethyl ester) (BAPTA-AM) or the three specific calcineurin inhibitors FK506, cyclosporine A, or calcineurin inhibitory peptide prevented bile acid-induced acinar cell injury as measured by lactate dehydrogenase leakage and propidium iodide uptake. The calcineurin inhibitors reduced the intra-acinar activation of chymotrypsinogen within 30 min of TLCS administration, and they also prevented NF-κB activation. In vivo, mice that received FK506 or were deficient in the calcineurin isoform Aβ (CnAβ) subunit had reduced pancreatitis severity after infusion of TLCS or taurocholic acid into the pancreatic duct. In summary, we demonstrate that acinar cell calcineurin is activated in response to Ca2+ generated by bile acid exposure, bile acid-induced pancreatic injury is dependent on calcineurin activation, and calcineurin inhibitors may provide an adjunctive therapy for biliary pancreatitis. 相似文献
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Larrieu D Thiébaud P Duplàa C Sibon I Thézé N Lamazière JM 《Experimental cell research》2005,310(1):166-175
Cellular mechanisms controlling smooth muscle cells (SMCs) phenotypic modulation are largely unknown. Intracellular Ca2+ movements are essential to ensure SMC functions; one of the roles of Ca2+ is to regulate calcineurin, which in turn induces nuclear localization of the nuclear factor of activated T-cell (NFAT). In order to investigate, during phenotypic differentiation of SMCs, the effect of calcineurin inhibition on NFAT2 nuclear translocation, we used a culture model of SMC differentiation in serum-free conditions. We show that the treatment of cultured SMC with the calcineurin inhibitor cyclosporine A induced their dedifferentiation while preventing their differentiation. These findings suggest that nuclear translocation of NFAT2 is dependent of calcineurin activity during the in vitro SMC differentiation kinetic and that the nuclear presence of NFAT2 is critical in the acquisition and maintenance of SMC differentiation. 相似文献
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Kamaldeen A. Muili Shunqian Jin Abrahim I. Orabi John F. Eisses Tanveer A. Javed Tianming Le Rita Bottino Thotalla Jayaraman Sohail Z. Husain 《The Journal of biological chemistry》2013,288(29):21065-21073
Biliary pancreatitis is the most common etiology of acute pancreatitis, accounting for 30–60% of cases. A dominant theory for the development of biliary pancreatitis is the reflux of bile into the pancreatic duct and subsequent exposure to pancreatic acinar cells. Bile acids are known to induce aberrant Ca2+ signals in acinar cells as well as nuclear translocation of NF-κB. In this study, we examined the role of the downstream Ca2+ target calcineurin on NF-κB translocation. Freshly isolated mouse acinar cells were infected for 24 h with an adenovirus expressing an NF-κB luciferase reporter. The bile acid taurolithocholic acid-3-sulfate caused NF-κB activation at concentrations (500 μm) that were associated with cell injury. We show that the NF-κB inhibitor Bay 11-7082 (1 μm) blocked translocation and injury. Pretreatment with the Ca2+ chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid, the calcineurin inhibitors FK506 and cyclosporine A, or use of acinar cells from calcineurin Aβ-deficient mice each led to reduced NF-κB activation with taurolithocholic acid-3-sulfate. Importantly, these manipulations did not affect LPS-induced NF-κB activation. A critical upstream regulator of NF-κB activation is protein kinase C, which translocates to the membranes of various organelles in the active state. We demonstrate that pharmacologic and genetic inhibition of calcineurin blocks translocation of the PKC-δ isoform. In summary, bile-induced NF-κB activation and acinar cell injury are mediated by calcineurin, and a mechanism for this important early inflammatory response appears to be upstream at the level of PKC translocation. 相似文献
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Background
Sildenafil, a potent phosphodiesterase type 5 (PDE5) inhibitor, has been proposed as a treatment for pulmonary arterial hypertension (PAH). The mechanism of its anti-proliferative effect on pulmonary artery smooth muscle cells (PASMC) is unclear. Nuclear translocation of nuclear factor of activated T-cells (NFAT) is thought to be involved in PASMC proliferation and PAH. Increase in cytosolic free [Ca2+] ([Ca2+]i) is a prerequisite for NFAT nuclear translocation. Elevated [Ca2+]i in PASMC of PAH patients has been demonstrated through up-regulation of store-operated Ca2+ channels (SOC) which is encoded by the transient receptor potential (TRP) channel protein. Thus we investigated if: 1) up-regulation of TRPC1 channel expression which induces enhancement of SOC-mediated Ca2+ influx and increase in [Ca2+]i is involved in hypoxia-induced PASMC proliferation; 2) hypoxia-induced promotion of [Ca2+]i leads to nuclear translocation of NFAT and regulates PASMC proliferation and TRPC1 expression; 3) the anti-proliferative effect of sildenafil is mediated by inhibition of this SOC/Ca2+/NFAT pathway.Methods
Human PASMC were cultured under hypoxia (3% O2) with or without sildenafil treatment for 72 h. Cell number and cell viability were determined with a hemocytometer and MTT assay respectively. [Ca2+]i was measured with a dynamic digital Ca2+ imaging system by loading PASMC with fura 2-AM. TRPC1 mRNA and protein level were detected by RT-PCR and Western blotting respectively. Nuclear translocation of NFAT was determined by immunofluoresence microscopy.Results
Hypoxia induced PASMC proliferation with increases in basal [Ca2+]i and Ca2+ entry via SOC (SOCE). These were accompanied by up-regulation of TRPC1 gene and protein expression in PASMC. NFAT nuclear translocation was significantly enhanced by hypoxia, which was dependent on SOCE and sensitive to SOC inhibitor SKF96365 (SKF), as well as cGMP analogue, 8-brom-cGMP. Hypoxia-induced PASMC proliferation and TRPC1 up-regulation were inhibited by SKF and NFAT blocker (VIVIT and Cyclosporin A). Sildenafil treatment ameliorated hypoxia-induced PASMC proliferation and attenuated hypoxia-induced enhancement of basal [Ca2+]i, SOCE, up-regulation of TRPC1 expression, and NFAT nuclear translocation.Conclusion
The SOC/Ca2+/NFAT pathway is, at least in part, a downstream mediator for the anti-proliferative effect of sildenafil, and may have therapeutic potential for PAH treatment. 相似文献13.
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Calcineurin is a Ca(2+)-dependent serine/threonine phosphatase and the target of the immunosuppressive drugs cyclosporin and tacrolimus, which are used in transplant recipients to prevent rejection. Unfortunately, the therapeutic use of this drugs is complicated by a high incidence of skin malignancy, which has set off a number of studies into the role of calcineurin signaling in skin, particularly with respect to cell cycle control and DNA repair. Both UVA1 radiation and arsenic species are known to promote skin cancer development via production of reactive oxygen species. In light of the well-documented sensitivity of calcineurin to oxidative stress, we examined and compared the effects of UVA1 and arsenite on calcineurin signaling. In this paper, we show that physiologically relevant doses of UVA1 radiation and low micromolar concentrations of arsenite strongly inhibit calcineurin phosphatase activity in Jurkat and skin cells and decrease NFAT nuclear translocation in Jurkat cells. The effects on calcineurin signaling could be partly prevented by inhibition of NADPH oxidase in Jurkat cells or increased dismutation of superoxide in Jurkat and skin cells. In addition, both UVA1 and arsenite decreased NF-κB activity, although at lower concentrations, arsenite enhanced NF-κB activity. These data indicate that UVA1 and arsenite affect a signal transduction route of growingly acknowledged importance in skin and that calcineurin may serve as a potential link between ROS exposure and impaired tumor suppression. 相似文献
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《Phytomedicine》2014,21(2):101-108
Sauchinone, a diastereomeric lignan isolated from the roots of Saururus chinensis (LOUR.) BAILL. (Saururaceae), is reported to exert a variety of biological activities such as hepatoprotective, anti-inflammatory actions and inhibitory effects on bone resorption. In this study, we investigated the effect of sauchinone in suppressing cell adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) expression in high glucose stimulated human umbilical vein endothelial cells (HUVEC). Sauchinone inhibited the phosphorylation and degradation of IκB-α, as well as the nuclear translocation of nuclear factor kappa B (NF-κB) p65 caused by the stimulation of high glucose. In addition, sauchinone induced heme oxygenase (HO)-1 expression through nuclear translocation of nuclear factor E2-related factor 2 in HUVEC. The effects of sauchinone on the high glucose-induced expression of VCAM-1 and ICAM-1 and nuclear translocation of NF-κB p65 were partially reversed by transfection of the cells with HO-1 siRNA. These findings suggest that sauchinone-induced HO-1 expression plays a key role in the vascular protective effects of sauchinone in HUVEC. 相似文献
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Cong Wang Ji-Feng Li Lan Zhao Jie Liu Jun Wan Yue Xiu Wang Jun Wang Chen Wang 《Respiratory research》2009,10(1):123
Background
Sildenafil, a potent phosphodiesterase type 5 (PDE5) inhibitor, has been proposed as a treatment for pulmonary arterial hypertension (PAH). The mechanism of its anti-proliferative effect on pulmonary artery smooth muscle cells (PASMC) is unclear. Nuclear translocation of nuclear factor of activated T-cells (NFAT) is thought to be involved in PASMC proliferation and PAH. Increase in cytosolic free [Ca2+] ([Ca2+]i) is a prerequisite for NFAT nuclear translocation. Elevated [Ca2+]i in PASMC of PAH patients has been demonstrated through up-regulation of store-operated Ca2+ channels (SOC) which is encoded by the transient receptor potential (TRP) channel protein. Thus we investigated if: 1) up-regulation of TRPC1 channel expression which induces enhancement of SOC-mediated Ca2+ influx and increase in [Ca2+]i is involved in hypoxia-induced PASMC proliferation; 2) hypoxia-induced promotion of [Ca2+]i leads to nuclear translocation of NFAT and regulates PASMC proliferation and TRPC1 expression; 3) the anti-proliferative effect of sildenafil is mediated by inhibition of this SOC/Ca2+/NFAT pathway.Methods
Human PASMC were cultured under hypoxia (3% O2) with or without sildenafil treatment for 72 h. Cell number and cell viability were determined with a hemocytometer and MTT assay respectively. [Ca2+]i was measured with a dynamic digital Ca2+ imaging system by loading PASMC with fura 2-AM. TRPC1 mRNA and protein level were detected by RT-PCR and Western blotting respectively. Nuclear translocation of NFAT was determined by immunofluoresence microscopy.Results
Hypoxia induced PASMC proliferation with increases in basal [Ca2+]i and Ca2+ entry via SOC (SOCE). These were accompanied by up-regulation of TRPC1 gene and protein expression in PASMC. NFAT nuclear translocation was significantly enhanced by hypoxia, which was dependent on SOCE and sensitive to SOC inhibitor (SKF), as well as cGMP analogue, 8-brom-cGMP. Hypoxia-induced PASMC proliferation and TRPC1 up-regulation were inhibited by SKF and NFAT blocker (VIVIT and Cyclosporin A). Sildenafil treatment ameliorated hypoxia-induced PASMC proliferation and attenuated hypoxia-induced enhancement of basal [Ca2+]i, SOCE, up-regulation of TRPC1 expression, and NFAT nuclear translocation. SKF96365Conclusion
The SOC/Ca2+/NFAT pathway is, at least in part, a downstream mediator for the anti-proliferative effect of sildenafil, and may have therapeutic potential for PAH treatment. 相似文献18.
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Zhen-Bo Liu 《Biochemical and biophysical research communications》2009,386(4):703-708