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Sample records for coordinately up-regulates protein

  1. Coordinately up-regulated genes in ovarian cancer.

    PubMed

    Hough, C D; Cho, K R; Zonderman, A B; Schwartz, D R; Morin, P J

    2001-05-15

    A better understanding of the molecular circuitry in normal ovarian tissues and in ovarian cancer will likely provide new targets for diagnosis and therapy. Recently, much has been learned about the genes expressed in ovarian cancer through studies with cDNA arrays and serial analysis of gene expression. However, these methods do not allow highly quantitative analysis of gene expression on a large number of specimens. Here, we have used quantitative real-time RT-PCR in a panel of 39 microdissected ovarian carcinomas of various subtypes to systematically analyze the expression of 13 genes, many of which were previously identified as up-regulated in a subset of ovarian cancers by serial analyses of gene expression. The genes analyzed are glutathione peroxidase 3 (GPX3), apolipoprotein J/clusterin, insulin-like growth factor-binding protein 2, epithelial cell adhesion molecule/GA733-2, Kop protease inhibitor, matrix gla protein, tissue inhibitor of metalloproteinase 3, folate receptor 1, S100A2, signal transducer and activator of transcription 1, secretory leukocyte protease inhibitor, apolipoprotein E, and ceruloplasmin. All of the genes were found overexpressed, some at extremely high levels, in the vast majority of ovarian carcinomas irrespective of the subtype. Interestingly, GPX3 was found at much higher levels in tumors with clear cell histology and may represent a biomarker for this subtype. Some of the genes studied here may thus represent targets for early detection ovarian cancer. The gene expression patterns were not associated with age at diagnosis, stage, or K-ras mutation status in ovarian cancer. We find that several genes are coordinately regulated in ovarian cancer, likely representing the fact that many genes are activated as part of common signaling pathways or that extensive cross-talk exists between several pathways in ovarian cancer. A statistical analysis shows that genes commonly up-regulated in ovarian cancer may result from the aberrant

  2. Up-Regulation of Antioxidant Proteins in the Plasma Proteome during Saturation Diving: Unique Coincidence under Hypobaric Hypoxia

    PubMed Central

    Domoto, Hideharu; Iwaya, Keiichi; Ikomi, Fumitaka; Matsuo, Hirotaka; Tadano, Yutaka; Fujii, Shigenori; Tachi, Kazuyoshi; Itoh, Yoshiyuki; Sato, Michiya; Inoue, Kimitoshi; Shinomiya, Nariyoshi

    2016-01-01

    Saturation diving (SD) is one of the safest techniques for tolerating hyperbaric conditions for long durations. However, the changes in the human plasma protein profile that occur during SD are unknown. To identify differential protein expression during or after SD, 65 blood samples from 15 healthy Japanese men trained in SD were analyzed by two-dimensional fluorescence difference gel electrophoresis. The expression of two proteins, one 32.4 kDa with an isoelectric point (pI) of 5.8 and the other 44.8 kDa with pI 4.0, were elevated during SD to 60, 100, and 200 meters sea water (msw). The expression of these proteins returned to pre-diving level when the SD training was completed. The two proteins were identified using in-gel digestion and mass spectrometric analysis; the 32.4 kDa protein was transthyretin and the 44.8 kDa protein was alpha-1-acid glycoprotein 1. Oxidation was detected at methionine 13 of transthyretin and at methionine 129 of alpha-1-acid glycoprotein 1 by tandem mass spectrometry. Moreover, haptoglobin was up-regulated during the decompression phase of 200 msw. These plasma proteins up-regulated during SD have a common function as anti-oxidants. This suggests that by coordinating their biological effects, these proteins activate a defense mechanism to counteract the effects of hyperbaric-hyperoxic conditions during SD. PMID:27741252

  3. Perforin and granzyme B. Cytolytic proteins up-regulated during rejection of rat small intestine allografts.

    PubMed

    McDiarmid, S V; Farmer, D G; Kuniyoshi, J S; Robert, M; Khadavi, A; Shaked, A; Busuttil, R W

    1995-03-15

    Perforin and granzyme B are 2 cytolytic proteins specific to activated killer cells, particularly CTL. We have studied the mRNA expression of these 2 proteins by a reverse transcriptase polymerase chain reaction method in a unidirectional model of rat small intestine transplant rejection. The allograft group consisted of Lewis x Brown Norway F1 donors into Lewis recipients. The isograft controls were Lewis donors into Lewis recipients. Grafts were placed heterotopically and no immunosuppression was given. Five animals in each group were killed at postoperative days (POD) 3, 5, 7, 8, 9, 10, 12, and 14. mRNA was extracted and a semiquantitative reverse transcriptase polymerase chain reaction was performed. For the semiquantitative analysis, we compared scintillation counts from excised bands. Results were expressed as a percent activity compared with beta-actin. From the same tissue samples, a histologic evaluation was made and rejection was graded according to severity. The isograft controls showed no evidence of histologic rejection and a very low expression of mRNA for perforin and granzyme B from POD 3-14. In contrast, the allograft group began to show histologic evidence of mild rejection on POD 5. By day 7, rejection was moderately severe and associated with a significant up-regulation of perforin and granzyme B in the allografts compared with the controls (P < 0.01), which persisted through POD 14. Peak expression for perforin and granzyme B was on POD 10 and 8, respectively. We conclude that the up-regulation of perforin and granzyme B in rat small intestine transplant allografts is a useful marker of clinically important rejection. PMID:7886805

  4. Protein kinase C mediates up-regulation of tetrodotoxin-resistant, persistent Na+ current in rat and mouse sensory neurones.

    PubMed

    Baker, Mark D

    2005-09-15

    The tetrodotoxin-resistant (TTX-r) persistent Na(+) current, attributed to Na(V)1.9, was recorded in small (< 25 mum apparent diameter) dorsal root ganglion (DRG) neurones cultured from P21 rats and from adult wild-type and Na(V)1.8 null mice. In conventional whole-cell recordings intracellular GTP-gamma-S caused current up-regulation, an effect inhibited by the PKC pseudosubstrate inhibitor, PKC19-36. The current amplitude was also up-regulated by 25 microM intracellular 1-oleoyl-2-acetyl-sn-glycerol (OAG) consistent with PKC involvement. In perforated-patch recordings, phorbol 12-myristate 13-acetate (PMA) up-regulated the current, whereas membrane-permeant activators of protein kinase A (PKA) were without effect. PGE(2) did not acutely up-regulate the current. Conversely, both PGE(2) and PKA activation up-regulated the major TTX-r Na(+) current, Na(V)1.8. Extracellular ATP up-regulated the persistent current with an average apparent K(d) near 13 microM, possibly consistent with P2Y receptor activation. Numerical simulation of the up-regulation qualitatively reproduced changes in sensory neurone firing properties. The activation of PKC appears to be a necessary step in the GTP-dependent up-regulation of persistent Na(+) current. PMID:16002450

  5. Curcumin Inhibits Prostate Cancer Bone Metastasis by Up-Regulating Bone Morphogenic Protein-7 in Vivo

    PubMed Central

    Dorai, Thambi; Diouri, Janane; O'Shea, Orla; Doty, Stephen B.

    2014-01-01

    A number of studies have focused on the beneficial properties of Curcumin (diferuloyl methane, used in South Asian cuisine and traditional medicine) such as the chemoprevention of cancer. Recent studies have also indicated that this material has significant benefits for the treatment of cancer and is currently undergoing several clinical trials. We have been interested in the application of this compound as a therapeutic agent for advanced prostate cancer, particularly the skeletal complications in this malignancy. Our earlier work indicated that this compound could inhibit the osteomimetic properties which occur in castration resistant prostate cancer cells, by interfering with the common denominators between these cancer cells and the bone cells in the metastatic tumor microenvironment, namely the osteoblasts and the osteoclast. We predicted that curcumin could break the vicious cycle of reciprocal stimulation that results in uncontrolled osteolysis in the bony matrix. In this work, we have evaluated the potential of this compound in inhibiting the bone metastasis of hormone refractory prostate cancer cells in an established animal model. Our results strongly suggest that curcumin modulates the TGF-β signaling that occurs due to bone matrix degradation by up-regulating the metastasis inhibitory bone morphogenic protein-7 (BMP- 7). This enhancement of BMP-7 in the context of TGF-βin the tumor microenvironment is shown to enhance the mesenchymal-to-epithelial transition. Most importantly, we show that as a result of BMP-7 up-regulation, a novel brown/beige adipogenic differentiation program is also up-regu- lated which plays a role in the inhibition of bone metastasis. Our results suggest that curcumin may subvert the TGF-βsignaling to an alternative adipogenic differentiation program in addition to the previously established interference with the osteomimetic properties, thus inhibiting the bone metastatic processes in a chemopreventive as well as therapeutic

  6. Curcumin Inhibits Prostate Cancer Bone Metastasis by Up-Regulating Bone Morphogenic Protein-7 in Vivo.

    PubMed

    Dorai, Thambi; Diouri, Janane; O'Shea, Orla; Doty, Stephen B

    2014-04-01

    A number of studies have focused on the beneficial properties of Curcumin (diferuloyl methane, used in South Asian cuisine and traditional medicine) such as the chemoprevention of cancer. Recent studies have also indicated that this material has significant benefits for the treatment of cancer and is currently undergoing several clinical trials. We have been interested in the application of this compound as a therapeutic agent for advanced prostate cancer, particularly the skeletal complications in this malignancy. Our earlier work indicated that this compound could inhibit the osteomimetic properties which occur in castration resistant prostate cancer cells, by interfering with the common denominators between these cancer cells and the bone cells in the metastatic tumor microenvironment, namely the osteoblasts and the osteoclast. We predicted that curcumin could break the vicious cycle of reciprocal stimulation that results in uncontrolled osteolysis in the bony matrix. In this work, we have evaluated the potential of this compound in inhibiting the bone metastasis of hormone refractory prostate cancer cells in an established animal model. Our results strongly suggest that curcumin modulates the TGF-β signaling that occurs due to bone matrix degradation by up-regulating the metastasis inhibitory bone morphogenic protein-7 (BMP- 7). This enhancement of BMP-7 in the context of TGF-βin the tumor microenvironment is shown to enhance the mesenchymal-to-epithelial transition. Most importantly, we show that as a result of BMP-7 up-regulation, a novel brown/beige adipogenic differentiation program is also up-regu- lated which plays a role in the inhibition of bone metastasis. Our results suggest that curcumin may subvert the TGF-βsignaling to an alternative adipogenic differentiation program in addition to the previously established interference with the osteomimetic properties, thus inhibiting the bone metastatic processes in a chemopreventive as well as therapeutic

  7. Caffeine Induces the Stress Response and Up-Regulates Heat Shock Proteins in Caenorhabditis elegans.

    PubMed

    Al-Amin, Mohammad; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

    2016-02-01

    Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

  8. Neonatal maternal separation up-regulates protein signalling for cell survival in rat hypothalamus.

    PubMed

    Irles, Claudine; Nava-Kopp, Alicia T; Morán, Julio; Zhang, Limei

    2014-05-01

    We have previously reported that in response to early life stress, such as maternal hyperthyroidism and maternal separation (MS), the rat hypothalamic vasopressinergic system becomes up-regulated, showing enlarged nuclear volume and cell number, with stress hyperresponsivity and high anxiety during adulthood. The detailed signaling pathways involving cell death/survival, modified by adverse experiences in this developmental window remains unknown. Here, we report the effects of MS on cellular density and time-dependent fluctuations of the expression of pro- and anti-apoptotic factors during the development of the hypothalamus. Neonatal male rats were exposed to 3 h-daily MS from postnatal days 2 to 15 (PND 2-15). Cellular density was assessed in the hypothalamus at PND 21 using methylene blue staining, and neuronal nuclear specific protein and glial fibrillary acidic protein immunostaining at PND 36. Expression of factors related to apoptosis and cell survival in the hypothalamus was examined at PND 1, 3, 6, 9, 12, 15, 20 and 43 by Western blot. Rats subjected to MS exhibited greater cell-density and increased neuronal density in all hypothalamic regions assessed. The time course of protein expression in the postnatal brain showed: (1) decreased expression of active caspase 3; (2) increased Bcl-2/Bax ratio; (3) increased activation of ERK1/2, Akt and inactivation of Bad; PND 15 and PND 20 were the most prominent time-points. These data indicate that MS can induce hypothalamic structural reorganization by promoting survival, suppressing cell death pathways, increasing cellular density which may alter the contribution of these modified regions to homeostasis.

  9. Hypoxia Induces Autophagy through Translational Up-Regulation of Lysosomal Proteins in Human Colon Cancer Cells

    PubMed Central

    Lai, Ming-Chih; Chang, Chiao-May; Sun, H. Sunny

    2016-01-01

    Hypoxia occurs in a wide variety of physiological and pathological conditions, including tumorigenesis. Tumor cells have to adapt to hypoxia by altering their gene expression and protein synthesis. Here, we showed that hypoxia inhibits translation through activation of PERK and inactivation of mTOR in human colon cancer HCT116 cells. Prolonged hypoxia (1% O2, 16 h) dramatically inhibits general translation in HCT116 cells, yet selected mRNAs remain efficiently translated under such a condition. Using microarray analysis of polysome- associated mRNAs, we identified a large number of hypoxia-regulated genes at the translational level. Efficiently translated mRNAs during hypoxia were validated by polysome profiling and quantitative real-time RT-PCR. Pathway enrichment analysis showed that many of the up-regulated genes are involved in lysosome, glycan and lipid metabolism, antigen presentation, cell adhesion, and remodeling of the extracellular matrix and cytoskeleton. The majority of down-regulated genes are involved in apoptosis, ubiquitin-mediated proteolysis, and oxidative phosphorylation. Further investigation showed that hypoxia induces lysosomal autophagy and mitochondrial dysfunction through translational regulation in HCT116 cells. The abundance of several translation factors and the mTOR kinase activity are involved in hypoxia-induced mitochondrial autophagy in HCT116 cells. Our studies highlight the importance of translational regulation for tumor cell adaptation to hypoxia. PMID:27078027

  10. Uncoupling protein-2 up-regulation and enhanced cyanide toxicity are mediated by PPAR{alpha} activation and oxidative stress

    SciTech Connect

    Zhang, X.; Li, L.; Prabhakaran, K.; Zhang, L.; Leavesley, H.B.; Borowitz, J.L.; Isom, G.E.

    2007-08-15

    Uncoupling protein 2 (UCP-2) is an inner mitochondrial membrane proton carrier that modulates mitochondrial membrane potential ({delta}{psi}{sub m}) and uncouples oxidative phosphorylation. We have shown that up-regulation of UCP-2 by Wy14,643, a selective peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) agonist, enhances cyanide cytotoxicity. The pathway by which Wy14,643 up-regulates UCP-2 was determined in a dopaminergic cell line (N27 cells). Since dopaminergic mesencephalic cells are a primary brain target of cyanide, the N27 immortalized mesencephalic cell was used in this study. Wy14,643 produced a concentration- and time-dependent up-regulation of UCP-2 that was linked to enhanced cyanide-induced cell death. MK886 (PPAR{alpha} antagonist) or PPAR{alpha} knock-down by RNA interference (RNAi) inhibited PPAR{alpha} activity as shown by the peroxisome proliferator response element-luciferase reporter assay, but only partially decreased up-regulation of UCP-2. The role of oxidative stress as an alternative pathway to UCP-2 up-regulation was determined. Wy14,643 induced a rapid surge of ROS generation and loading cells with glutathione ethyl ester (GSH-EE) or pre-treatment with vitamin E attenuated up-regulation of UCP-2. On the other hand, RNAi knockdown of PPAR{alpha} did not alter ROS generation, suggesting a PPAR{alpha}-independent component to the response. Co-treatment with PPAR{alpha}-RNAi and GSH-EE blocked both the up-regulation of UCP-2 by Wy14,643 and the cyanide-induced cell death. It was concluded that a PPAR{alpha}-mediated pathway and an oxidative stress pathway independent of PPAR{alpha} mediate the up-regulation of UCP-2 and subsequent increased vulnerability to cyanide-induced cytotoxicity.

  11. Oncogenic viral protein HPV E7 up-regulates the SIRT1 longevity protein in human cervical cancer cells.

    PubMed

    Allison, Simon J; Jiang, Ming; Milner, Jo

    2009-03-02

    Senescence is blocked in human cervical keratinocytes infected with high risk human papillomavirus (e.g. HPV type16). Viral oncoproteins HPV E6 and HPV E7 access the cell cycle via cellular p53 and retinoblastoma proteins respectively. Previously we have shown that HPV E7, not HPV E6, is also responsible for cervical cancer cell survival (SiHa cells; HPV type16). We now present evidence that SIRT1, an aging-related NAD-dependent deacetylase, mediates HPV E7 survival function in SiHa cervical cancer cells. Moreover, HPV E7 up-regulates SIRT1 protein when expressed in primary human keratinocytes. Conversely, SIRT1 levels decrease following RNAi-mediated silencing of HPV E7 in SiHa cells. Silencing HPV E6 has no effect on SIRT1 but, as expected, causes marked accumulation of p53 protein accompanied by p53-mediated up-regulation of p21. However, p53 acetylation (K382Ac) was barely detectable. Since p53 is a known SIRT1 substrate we propose that elevated SIRT1 levels (induced by HPV E7) attenuate p53 pro-apoptotic capacity via its de-acetylation. Our discovery that HPV E7 up-regulates SIRT1 links a clinically important oncogenic virus with the multi-functional SIRT1 protein. This link may open the way for a more in-depth understanding of the process of HPV-induced malignant transformation and also of the inter-relationships between aging and cancer.

  12. G-protein Receptor Kinase 5 Regulates the Cannabinoid Receptor 2-induced Up-regulation of Serotonin 2A Receptors*

    PubMed Central

    Franklin, Jade M.; Carrasco, Gonzalo A.

    2013-01-01

    We have recently reported that cannabinoid agonists can up-regulate and enhance the activity of serotonin 2A (5-HT2A) receptors in the prefrontal cortex (PFCx). Increased expression and activity of cortical 5-HT2A receptors has been associated with neuropsychiatric disorders, such as anxiety and schizophrenia. Here we report that repeated CP55940 exposure selectively up-regulates GRK5 proteins in rat PFCx and in a neuronal cell culture model. We sought to examine the mechanism underlying the regulation of GRK5 and to identify the role of GRK5 in the cannabinoid agonist-induced up-regulation and enhanced activity of 5-HT2A receptors. Interestingly, we found that cannabinoid agonist-induced up-regulation of GRK5 involves CB2 receptors, β-arrestin 2, and ERK1/2 signaling because treatment with CB2 shRNA lentiviral particles, β-arrestin 2 shRNA lentiviral particles, or ERK1/2 inhibitor prevented the cannabinoid agonist-induced up-regulation of GRK5. Most importantly, we found that GRK5 shRNA lentiviral particle treatment prevented the cannabinoid agonist-induced up-regulation and enhanced 5-HT2A receptor-mediated calcium release. Repeated cannabinoid exposure was also associated with enhanced phosphorylation of CB2 receptors and increased interaction between β-arrestin 2 and ERK1/2. These latter phenomena were also significantly inhibited by GRK5 shRNA lentiviral treatment. Our results suggest that sustained activation of CB2 receptors, which up-regulates 5-HT2A receptor signaling, enhances GRK5 expression; the phosphorylation of CB2 receptors; and the β-arrestin 2/ERK interactions. These data could provide a rationale for some of the adverse effects associated with repeated cannabinoid agonist exposure. PMID:23592773

  13. Resveratrol up-regulates AMPA receptor expression via AMP-activated protein kinase-mediated protein translation.

    PubMed

    Wang, Guan; Amato, Stephen; Gilbert, James; Man, Heng-Ye

    2015-08-01

    Resveratrol is a phytoalexin that confers overall health benefits including positive regulation in brain function such as learning and cognition. However, whether and how resveratrol affects synaptic activity remains largely unknown. α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) are glutamatergic receptors that mediate the majority of fast excitatory transmission and synaptic plasticity, and thus play a critical role in higher brain functions, including learning and memory. We find that in rat primary neurons, resveratrol can rapidly increase AMPAR protein level, AMPAR synaptic accumulation and the strength of excitatory synaptic transmission. The resveratrol effect on AMPAR protein expression is independent of sirtuin 1 (SIRT1), the conventional downstream target of resveratrol, but rather is mediated by AMP-activated protein kinase (AMPK) and subsequent downstream phosphoinositide 3-kinase (PI3K)/Akt signaling. Application of the AMPK specific activator 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) mimics the effects of resveratrol on both signaling and AMPAR expression. The resveratrol-induced increase in AMPAR expression results from elevated protein synthesis via regulation of the eukaryotic initiation factor (eIF) 4E/4G complex. Disruption of the translation initiation complex completely blocks resveratrol-dependent AMPAR up-regulation. These findings indicate that resveratrol may regulate brain function through facilitation of AMPAR biogenesis and synaptic transmission.

  14. Uncoupling Protein-2 is an Antioxidant that is Up-Regulated in the Enamel Organ of Fluoride-Treated Rats*

    PubMed Central

    Suzuki, Maiko; Sierant, Megan L.; Antone, Jerry V.; Everett, Eric T.; Whitford, Gary M.; Bartlett, John D.

    2014-01-01

    Dental fluorosis is characterized by subsurface hypomineralization and retention of enamel matrix proteins. Fluoride (F−) exposure generates reactive oxygen species (ROS) that can cause ER-stress. We therefore screened oxidative stress arrays to identify genes regulated by F− exposure. Vitamin E is an antioxidant so we asked if a diet high in vitamin E would attenuate dental fluorosis. Maturation stage incisor enamel organs (EO) were harvested from F− treated rats and mice were assessed to determine if vitamin E ameliorates dental fluorosis. Uncoupling protein-2 (Ucp2) was significantly up-regulated by F− (~1.5 & 2.0 fold for the 50 or 100 ppm F− treatment groups respectively). Immunohistochemical results on maturation stage rat incisors demonstrated that UCP2 protein levels increased with F− treatment. UCP2 down-regulates mitochondrial production of ROS, which decreases ATP production. Thus, in addition to reduced protein translation caused by ER-stress, a reduction in ATP production by UCP2 may contribute to the inability of ameloblasts to remove protein from the hardening enamel. Fluoride treated mouse enamel had significantly higher quantitative fluorescence (QF) than the untreated controls. No significant QF difference was observed between control and vitamin E enriched diets within a given F− treatment group. Therefore, a diet rich in vitamin E did not attenuate dental fluorosis. We have identified a novel oxidative stress response gene that is up-regulated in vivo by F− and activation of this gene may adversely affect ameloblast function. PMID:25158175

  15. Pregnancy-associated plasma protein A up-regulated by progesterone promotes adhesion and proliferation of trophoblastic cells.

    PubMed

    Wang, Jiao; Liu, Shuai; Qin, Hua-Min; Zhao, Yue; Wang, Xiao-Qi; Yan, Qiu

    2014-01-01

    Embryo implantation and development is a complex biological process for the establishment of the successful pregnancy. Progesterone is a critical factor in the regulation of embryo adhesion to uterine endometrium and proliferation. Although it has been reported that pregnancy-associated plasma protein A (PAPPA) is increased in pregnant women, the relationship between progesterone and PAPPA, and the effects of PAPPA on embryo adhesion and proliferation are still not clear. The present results showed that the serum level of progesterone and PAPPA was closely correlated by ELISA assay (p<0.01). PAPPA was detected in the villi of early embryo by RT-PCR, Western blot, immunohistochemistry and immunofluorescent staining. Moreover, PAPPA was significantly up-regulated by progesterone in trophoblastic (JAR) cells by Real-time PCR and ELISA assay (p<0.01); while the expression was decreased by the progesterone receptor inhibitor RU486. The down-regulation of PAPPA by siRNA transfection or up-regulation of PAPPA by progesterone treatment significantly decreased or increased the adhesion rate of trophoblastic cells to human uterine epithelial cell lines (RL95-2 and HEC-1A), respectively (p<0.01), as well as the proliferation of trophoblastic cells. In conclusion, PAPPA is up-regulated by progesterone, which promotes the adhesion and proliferation potential of trophoblastic cells. PMID:24817938

  16. Nitrosative stress leads to protein glutathiolation, increased s-nitrosation, and up-regulation of peroxiredoxins in the heart.

    PubMed

    Reinartz, Michael; Ding, Zhaoping; Flögel, Ulrich; Gödecke, Axel; Schrader, Jürgen

    2008-06-20

    Nitric oxide (NO) is produced by different isoforms of nitric oxide synthases (NOSs) and operates as a mediator of important cell signaling pathways, such as the cGMP signaling cascade. Another mechanism by which NO exerts biological effects is mediated through S-nitrosation of target proteins. To explore thiol-based protein modifications in a situation of defined nitrosative stress, we used a transgenic mouse model with cardiac specific overexpression of inducible nitric oxide synthase (iNOS) and concomitant myoglobin deficiency (iNOS(+)/myo(-/-)). In comparison with the wild type hearts, protein glutathiolation detected by immunoblotting was significantly enhanced in iNOS(+)/myo(-/-) hearts, whereas protein S-nitrosation as measured by the biotin switch assay and two-dimensional PAGE revealed that nearly all of the detected proteins ( approximately 60) remained unchanged with the exception of three proteins. Tandem mass spectrometry revealed these proteins to be peroxiredoxins (Prxs), which are known to possess peroxidase activity, whereby hydrogen peroxide, peroxynitrite, and a wide range of organic hydroperoxides are reduced and detoxified. Immunoblotting with specific antibodies revealed up-regulation of Prx VI in the iNOS(+)/myo(-/-) hearts, whereas expression of Prx II and Prx III remained unchanged. Furthermore, the analysis of the cardiac S-nitrososubproteome identified several new proteins possibly being involved in NO-signaling pathways. Our data indicate that S-nitrosation and glutathiolation of cardiac proteins may contribute to the phenotype of NO-induced heart failure. The up-regulation of antioxidant proteins like Prx VI appears to be an additional mechanism to antagonize an excess of reactive oxygen/nitrogen species. Furthermore, S-nitrosation of Prxs may serve a new function in the signaling cascade of nitrosative stress. PMID:18426799

  17. Nitrosative stress leads to protein glutathiolation, increased s-nitrosation, and up-regulation of peroxiredoxins in the heart.

    PubMed

    Reinartz, Michael; Ding, Zhaoping; Flögel, Ulrich; Gödecke, Axel; Schrader, Jürgen

    2008-06-20

    Nitric oxide (NO) is produced by different isoforms of nitric oxide synthases (NOSs) and operates as a mediator of important cell signaling pathways, such as the cGMP signaling cascade. Another mechanism by which NO exerts biological effects is mediated through S-nitrosation of target proteins. To explore thiol-based protein modifications in a situation of defined nitrosative stress, we used a transgenic mouse model with cardiac specific overexpression of inducible nitric oxide synthase (iNOS) and concomitant myoglobin deficiency (iNOS(+)/myo(-/-)). In comparison with the wild type hearts, protein glutathiolation detected by immunoblotting was significantly enhanced in iNOS(+)/myo(-/-) hearts, whereas protein S-nitrosation as measured by the biotin switch assay and two-dimensional PAGE revealed that nearly all of the detected proteins ( approximately 60) remained unchanged with the exception of three proteins. Tandem mass spectrometry revealed these proteins to be peroxiredoxins (Prxs), which are known to possess peroxidase activity, whereby hydrogen peroxide, peroxynitrite, and a wide range of organic hydroperoxides are reduced and detoxified. Immunoblotting with specific antibodies revealed up-regulation of Prx VI in the iNOS(+)/myo(-/-) hearts, whereas expression of Prx II and Prx III remained unchanged. Furthermore, the analysis of the cardiac S-nitrososubproteome identified several new proteins possibly being involved in NO-signaling pathways. Our data indicate that S-nitrosation and glutathiolation of cardiac proteins may contribute to the phenotype of NO-induced heart failure. The up-regulation of antioxidant proteins like Prx VI appears to be an additional mechanism to antagonize an excess of reactive oxygen/nitrogen species. Furthermore, S-nitrosation of Prxs may serve a new function in the signaling cascade of nitrosative stress.

  18. Carboxypeptidase E protects hippocampal neurons during stress in male mice by up-regulating prosurvival BCL2 protein expression.

    PubMed

    Murthy, S R K; Thouennon, E; Li, W-S; Cheng, Y; Bhupatkar, J; Cawley, N X; Lane, M; Merchenthaler, I; Loh, Y P

    2013-09-01

    Prolonged chronic stress causing elevated plasma glucocorticoids leads to neurodegeneration. Adaptation to stress (allostasis) through neuroprotective mechanisms can delay this process. Studies on hippocampal neurons have identified carboxypeptidase E (CPE) as a novel neuroprotective protein that acts extracellularly, independent of its enzymatic activity, although the mechanism of action is unclear. Here, we aim to determine if CPE plays a neuroprotective role in allostasis in mouse hippocampus during chronic restraint stress (CRS), and the molecular mechanisms involved. Quantitative RT-PCR/in situ hybridization and Western blots were used to assay for mRNA and protein. After mild CRS (1 h/d for 7 d), CPE protein and mRNA were significantly elevated in the hippocampal CA3 region, compared to naïve littermates. In addition, luciferase reporter assays identified a functional glucocorticoid regulatory element within the cpe promoter that mediated the up-regulation of CPE expression in primary hippocampal neurons following dexamethasone treatment, suggesting that circulating plasma glucocorticoids could evoke a similar effect on CPE in the hippocampus in vivo. Overexpression of CPE in hippocampal neurons, or CRS in mice, resulted in elevated prosurvival BCL2 protein/mRNA and p-AKT levels in the hippocampus; however, CPE(-/-) mice showed a decrease. Thus, during mild CRS, CPE expression is up-regulated, possibly contributed by glucocorticoids, to mediate neuroprotection of the hippocampus by enhancing BCL2 expression through AKT signaling, and thereby maintaining allostasis.

  19. Estrogen-dependent up-regulation of TRPA1 and TRPV1 receptor proteins in the rat endometrium.

    PubMed

    Pohóczky, Krisztina; Kun, József; Szalontai, Bálint; Szőke, Éva; Sághy, Éva; Payrits, Maja; Kajtár, Béla; Kovács, Krisztina; Környei, József László; Garai, János; Garami, András; Perkecz, Anikó; Czeglédi, Levente; Helyes, Zsuzsanna

    2016-02-01

    Transient receptor potential ankyrin 1 (TRPA1) and vanilloid 1 (TRPV1) receptors expressed predominantly in sensory nerves are activated by inflammatory stimuli and mediate inflammation and pain. Although they have been shown in the human endometrium, their regulation and function are unknown. Therefore, we investigated their estrogen- and progesterone-dependent alterations in the rat endometrium in comparison with the estrogen-regulated inflammatory cytokine macrophage migration inhibitory factor (MIF). Four-week-old (sexually immature) and four-month-old (sexually mature) female rats were treated with the non-selective estrogen receptor (ER) agonist diethylstilboestrol (DES), progesterone and their combination, or ovariectomized. RT-PCR and immunohistochemistry were performed to determine mRNA and protein expression levels respectively. Channel function was investigated with ratiometric [Ca(2+)]i measurement in cultured primary rat endometrial cells. Both TRP receptors and MIF were detected in the endometrium at mRNA and protein levels, and their localizations were similar. Immunostaining was observed in the immature epithelium, while stromal, glandular and epithelial positivity were observed in adults. Functionally active TRP receptor proteins were shown in endometrial cells by activation-induced calcium influx. In adults, Trpa1 and Trpv1 mRNA levels were significantly up-regulated after DES treatment. TRPA1 increased after every treatment, but TRPV1 remained unchanged following the combined treatment and ovariectomy. In immature rats, DES treatment resulted in increased mRNA expression of both channels and elevated TRPV1 immunopositivity. MIF expression changed in parallel with TRPA1/TRPV1 in most cases. DES up-regulated Trpa1, Trpv1 and Mif mRNA levels in endometrial cell cultures, but 17β-oestradiol having ERα-selective potency increased only the expression of Trpv1. We provide the first evidence for TRPA1/TRPV1 expression and their estrogen-induced up-regulation

  20. Galectin-9 Protein Is Up-regulated in Astrocytes by Tumor Necrosis Factor and Promotes Encephalitogenic T-cell Apoptosis*

    PubMed Central

    Steelman, Andrew J.; Smith, Roger; Welsh, C. Jane; Li, Jianrong

    2013-01-01

    Demyelination and axonal damage in multiple sclerosis (MS) are thought to be a consequence of inflammatory processes that are perpetuated by activated glia and infiltrating leukocytes. Galectin-9 is a β-galactoside binding lectin capable of modulating immune responses and appears to be up-regulated in MS. However, its role in the pathogenesis of MS has yet to be determined. Here, we report that proinflammatory cytokines induce galectin-9 (Gal-9) expression in primary astrocytes and the mechanism by which TNF up-regulates Gal-9. Astrocytes did not express Gal-9 under basal conditions nor did IL-6, IL-10, or IL-13 trigger Gal-9 expression. In contrast, IL-1β, IFN-γ, and particularly TNF up-regulated Gal-9 in astrocytes. TNF-induced Gal-9 expression was dependent on TNF receptor 1 (TNFR1) as TNF failed to induce Gal-9 in TNFR1−/− astrocytes. Blockade of the JNK MAP kinase pathway with the JNK inhibitor SP600125 abrogated TNF-induced Gal-9, whereas p38 and MEK inhibitors had minimal effects. Furthermore, specific knockdown of c-Jun via siRNA in astrocytes before TNF treatment greatly suppressed Gal-9 transcription, suggesting that TNF induces astroglial Gal-9 through the TNF/TNFR1/JNK/cJun signaling pathway. Finally, utilizing astrocytes from Lgals9 mutant (Gal-9−/−) mice as well as a myelin basic protein-specific Tim-3+ encephalitogenic T-cell clone (LCN-8), we found that conditioned medium from TNF-stimulated Gal-9+/+ but not Gal-9−/− astrocytes increased the percentage of apoptotic encephalitogenic T-cells. Together, our results suggest that Gal-9 is induced in astrocytes by TNF via the JNK/c-Jun pathway and that astrocyte-derived Gal-9 may function as an immunoregulatory protein in response to ongoing neuroinflammation. PMID:23836896

  1. Up-regulation of endothelial monocyte chemoattractant protein-1 by coplanar PCB77 is caveolin-1-dependent

    SciTech Connect

    Majkova, Zuzana; Smart, Eric; Toborek, Michal; Hennig, Bernhard

    2009-05-15

    Atherosclerosis, the primary cause of heart disease and stroke is initiated in the vascular endothelium, and risk factors for its development include environmental exposure to persistent organic pollutants. Caveolae are membrane microdomains involved in regulation of many signaling pathways, and in particular in endothelial cells. We tested the hypothesis that intact caveolae are required for coplanar PCB77-induced up-regulation of monocyte chemoattractant protein-1 (MCP-1), an endothelium-derived chemokine that attracts monocytes into sub-endothelial space in early stages of the atherosclerosis development. Atherosclerosis-prone LDL-R{sup -/-} mice (control) or caveolin-1{sup -/-}/LDL-R{sup -/-} mice were treated with PCB77. PCB77 induced aortic mRNA expression and plasma protein levels of MCP-1 in control, but not caveolin-1{sup -/-}/LDL-R{sup -/-} mice. To study the mechanism of this effect, primary endothelial cells were used. PCB77 increased MCP-1 levels in endothelial cells in a time- and concentration-dependent manner. This effect was abolished by caveolin-1 silencing using siRNA. Also, MCP-1 up-regulation by PCB77 was prevented by inhibiting p38 and c-Jun N-terminal kinase (JNK), but not ERK1/2, suggesting regulatory functions via p38 and JNK MAPK pathways. Finally, pre-treatment of endothelial cells with the aryl hydrocarbon receptor (AhR) inhibitor {alpha}-naphthoflavone ({alpha}-NF) partially blocked MCP-1 up-regulation. Thus, our data demonstrate that coplanar PCB77 can induce MCP-1 expression by endothelial cells and that this effect is mediated by AhR, as well as p 38 and JNK MAPK pathways. Intact caveolae are required for these processes both in vivo and in vitro. This further supports a key role for caveolae in vascular inflammation induced by persistent organic pollutants.

  2. Coordinate up-regulation of low-density lipoprotein receptor and cyclo-oxygenase-2 gene expression in human colorectal cells and in colorectal adenocarcinoma biopsies

    NASA Technical Reports Server (NTRS)

    Lum, D. F.; McQuaid, K. R.; Gilbertson, V. L.; Hughes-Fulford, M.

    1999-01-01

    Many colorectal cancers have high levels of cyclo-oxygenase 2 (COX-2), an enzyme that metabolizes the essential fatty acids into prostaglandins. Since the low-density lipoprotein receptor (LDLr) is involved in the uptake of essential fatty acids, we studied the effect of LDL on growth and gene regulation in colorectal cancer cells. DiFi cells grown in lipoprotein-deficient sera (LPDS) grew more slowly than cells with LDL. LDLr antibody caused significant inhibition of tumor cell growth but did not affect controls. In addition, LDL uptake did not change in the presence of excess LDL, suggesting that ldlr mRNA lacks normal feedback regulation in some colorectal cancers. Analysis of the ldlr mRNA showed that excess LDL in the medium did not cause down-regulation of the message even after 24 hr. The second portion of the study examined the mRNA expression of ldlr and its co-regulation with cox-2 in normal and tumor specimens from patients with colorectal adenocarcinomas. The ratio of tumor:paired normal mucosa of mRNA expression of ldlr and of cox-2 was measured in specimens taken during colonoscopy. ldlr and cox-2 transcripts were apparent in 11 of 11 carcinomas. There was significant coordinate up-regulation both of ldlr and of cox-2 in 6 of 11 (55%) tumors compared with normal colonic mucosa. There was no up-regulation of cox-2 without concomitant up-regulation of ldlr. These data suggest that the LDLr is abnormally regulated in some colorectal tumors and may play a role in the up-regulation of cox-2. Copyright 1999 Wiley-Liss, Inc.

  3. Protein malnutrition up-regulates growth hormone receptor expression in rat splenic B lymphocytes.

    PubMed

    Mejía-Naranjo, Wilson; Sánchez-Gomez, Myriam

    2004-12-01

    The reciprocal interaction between the endocrine and immune systems has been the subject of active research during the last decade, and an important body of evidence has accumulated supporting the role of the GH/IGF axis in immune function. More recently, the GH/IGF axis has been postulated as playing an important role in the modulation of stress conditions, such as catabolic stages, aging-related disorders, immunodeficient aids patients and malnutrition. Whether these effects are exerted through endocrine, autocrine or paracrine mechanisms remains to be determined for different immune cell types and tissues. The aim of the current study was to define which specific subsets of lymphocytes are the primary targets for GH action. In addition, the regulatory role of stress induced by protein restriction was investigated with respect to the relative distribution of GH receptor positive lymphoid cells. Normal growing rats were fed isocaloric diets with variable protein content (0, 4, 8, 12 and 20%) for a period of 14 days. The lymphoid cells were then separated from spleen, lymph nodes and peripheral blood lymphocytes. Flow cytometry analysis measured the binding characteristics of Fluos-rrGH to lymphocytes together with specific PE-labelled mAbs defining CD4+ and CD8+ T cells and B lymphocytes. The pattern of expression of the GH receptor differed among the lymphoid tissues and cell subsets. Spleen was the most responsive organ to protein deprivation with highest GH receptor expression in B lymphocytes, followed by CD4+ T cells. As the protein intake was decreased from 20% to 0%, the percentage of GHR positive cells increased from 12% to 52% in splenic B lymphocytes and from 8% to 17% in CD4+ T cells. In contrast, only 10%-13% of lymphocytes in lymph nodes and 2%-4% in circulation, showed binding sites to GH associated with protein deprivation. In conclusion, the increase in GH receptors on lymphocytes under catabolic stress induced by protein malnutrition gives support

  4. Antithrombin up-regulates AMP-activated protein kinase signalling during myocardial ischaemia/reperfusion injury.

    PubMed

    Ma, Yina; Wang, Jinli; Gao, Junjie; Yang, Hui; Wang, Yanqing; Manithody, Chandrashekhara; Li, Ji; Rezaie, Alireza R

    2015-02-01

    Antithrombin (AT) is a protein of the serpin superfamily involved in regulation of the proteolytic activity of the serine proteases of the coagulation system. AT is known to exhibit anti-inflammatory and cardioprotective properties when it binds to heparan sulfate proteoglycans (HSPGs) on vascular cells. AMP-activated protein kinase (AMPK) plays an important cardioprotective role during myocardial ischaemia and reperfusion (I/R). To determine whether the cardioprotective signaling function of AT is mediated through the AMPK pathway, we evaluated the cardioprotective activities of wild-type AT and its two derivatives, one having high affinity and the other no affinity for heparin, in an acute I/R injury model in C57BL/6J mice in which the left anterior descending coronary artery was occluded. The serpin derivatives were given 5 minutes before reperfusion. The results showed that AT-WT can activate AMPK in both in vivo and ex vivo conditions. Blocking AMPK activity abolished the cardioprotective function of AT against I/R injury. The AT derivative having high affinity for heparin was more effective in activating AMPK and in limiting infraction, but the derivative lacking affinity for heparin was inactive in eliciting AMPK-dependent cardioprotective activity. Activation of AMPK by AT inhibited the inflammatory c-Jun N-terminal protein kinase (JNK) pathway during I/R. Further studies revealed that the AMPK activity induced by AT also modulates cardiac substrate metabolism by increasing glucose oxidation but inhibiting fatty acid oxidation during I/R. These results suggest that AT binds to HSPGs on heart tissues to invoke a cardioprotective function by triggering cardiac AMPK activation, thereby attenuating JNK inflammatory signalling pathways and modulating substrate metabolism during I/R. PMID:25230600

  5. Fibrinogen up-regulates the expression of monocyte chemoattractant protein 1 in human saphenous vein endothelial cells.

    PubMed Central

    Harley, S L; Powell, J T

    1999-01-01

    High concentrations of fibrinogen in plasma have been associated with an increased risk of saphenous vein graft pathology. We have investigated the ability of fibrinogen to up-regulate the expression of monocyte chemoattractant protein 1 (MCP-1) in cultured human saphenous vein endothelial cells (HSVEC) isolated from saphenous vein. Increasing concentrations of fibrinogen (0-4 microM) stimulated a 20-fold increase in MCP-1 secretion within 4 h. Incubation of HSVEC with 2 microM fibrinogen for 4 h also caused a 2-fold increase in the MCP-1-to-glyceraldehyde-3-phosphate dehydrogenase mRNA ratio. The fibrinogen-mediated MCP-1 secretion fell to basal levels after preincubation of HSVEC with the complex of fibrinogen fragments D and E but remained unchanged after preincubation of HSVEC with either fibrinogen fragment E, s-ICAM-1 or the pentapeptide GRGDV. In contrast, fibrinogen fragment D acted as a potent inhibitor of fibrinogen-mediated MCP-1 secretion. Labelled fibrinogen fragment D bound to HSVEC with a K(d) of 6.5 microM. These findings indicate that fibrinogen, at physiological concentrations, uses an epitope on the fibrinogen D domain to bind to a receptor on HSVEC to up-regulate MCP-1 expression and secretion. This receptor seems to be distinct from intercellular adhesion molecule 1 and the integrins previously recognized as fibrinogen receptors. PMID:10417339

  6. Acetylation of p53 Protein at Lysine 120 Up-regulates Apaf-1 Protein and Sensitizes the Mitochondrial Apoptotic Pathway.

    PubMed

    Yun, Tao; Yu, Kaiwen; Yang, ShuangShuang; Cui, Yifan; Wang, Zixi; Ren, Huiyu; Chen, She; Li, Lin; Liu, Xiaoyun; Fang, Min; Jiang, Xuejun

    2016-04-01

    The p53 tumor suppressor controls cell growth, metabolism, and death by regulating the transcription of various target genes. The target-specific transcriptional activity of p53 is highly regulated. Here we demonstrate that acetylation of p53 at Lys-120 up-regulates its transcriptional activity toward Apaf-1, a core component in the mitochondrial apoptotic pathway, and thus sensitizes caspase activation and apoptosis. We found that histone deacetylase (HDAC) inhibitors, including butyrate, augment Lys-120 acetylation of p53 and thus Apaf-1 expression by inhibiting HDAC1. In p53-null cells, transfection of wild-type but not K120R mutant p53 can restore the p53-dependent sensitivity to butyrate. Strikingly, transfection of acetylation-mimicking K120Q mutant p53 is sufficient to up-regulates Apaf-1 in a manner independent of butyrate treatment. Therefore, HDAC inhibitors can induce p53 acetylation at lysine 120, which in turn enhances mitochondrion-mediated apoptosis through transcriptional up-regulation of Apaf-1. PMID:26851285

  7. Ephrin-A1 Is Up-Regulated by Hypoxia in Cancer Cells and Promotes Angiogenesis of HUVECs through a Coordinated Cross-Talk with eNOS

    PubMed Central

    Song, Kai; Shang, Zheng-Jun

    2013-01-01

    Hypoxia, ephrin-A1 and endothelial nitric oxide synthase (eNOS) have been proved to play critical roles in tumor angiogenesis. However, how ephrin-A1 is regulated by hypoxia and whether ephrin-A1 cooperates with eNOS in modulation of angiogenesis remain to be addressed in details. Here we demonstrated that both ephrin-A1 in squamous cell carcinoma cells (SCC-9) and especially soluble ephrin-A1 in the supernatants were up-regulated under hypoxic condition. An increased nitric oxide (NO) production in human umbilical vein endothelial cells (HUVECs) was observed in ephrin-A1-induced angiogenesis which was reversed after co-culture with eNOS specific inhibitor, N-nitro-L-arginine methyl ester hydrochloride (L-NAME). Western blot analysis confirmed that both phosphorylation of AktSer473 and eNOSSer1177 were up-regulated in ephrin-A1-stimulated HUVECs, with the total eNOS expression unchanged. The specific inhibitor of phosphatidylinositol 3-kinase (PI3K), LY294002, significantly down-regulated ephrin-A1-induced expression of phosphorylated AktSer473 as well as phosphorylation of eNOSSer1177. These results revealed a possible novel mechanism whereby ephrin-A1 is regulated in tumor microenvironment and promotes angiogenesis through a coordinated cross-talk with PI3K/Akt-dependent eNOS activation which may relate to normal vascular development and tumor neovascularization. PMID:24040255

  8. Body fat mass reduction and up-regulation of uncoupling protein by novel lipolysis-promoting plant extract.

    PubMed

    Mori, Shinobu; Satou, Mayumi; Kanazawa, Satoshi; Yoshizuka, Naonobu; Hase, Tadashi; Tokimitsu, Ichiro; Takema, Yoshinori; Nishizawa, Yoshinori; Yada, Toshihiko

    2009-01-01

    We have found natural products exhibiting lipolysis-promoting activity in subcutaneous adipocytes, which are less sensitive to hormones than visceral adipocytes. The activities and a action mechanisms of a novel plant extract of Cirsium oligophyllum (CE) were investigated in isolated adipocytes from rat subcutaneous fat, and its fat-reducing effects by peroral administration and topical application were evaluated in vivo. CE-induced lipolysis was synergistically enhanced by caffeine, a phosphodiesterase inhibitor, and was reduced by propranolol, a beta adrenergic antagonist. The peroral administration of 10% CE solution to Wistar rats for 32 days reduced body weight gain, subcutaneous, and visceral fat weights by 6.6, 26.2, and 3.0%, respectively, as compared to the control group. By the topical application of 2% of this extract to rats for 7 days, weight of subcutaneous fat in the treated skin was reduced by 23.2%. This fat mass reduction was accompanied by the up-regulation of uncoupling protein 1 (UCP), a principal thermogenic mitochondrial molecule related to energy dissipating, in subcutaneous fat and UCP3 in skin except for the fat layer. These results indicate that CE promotes lipolysis via a mechanism involving the beta adrenergic receptor, and affects the body fat mass. This fat reduction may be partially due to UCP up-regulation in the skin including subcutaneous fat. This is the first report showing that repeated lipolysis promotion through CE administration may be beneficial for the systematic suppression of body fat accumulation or the control of fat distribution in obesity.

  9. Six1 induces protein synthesis signaling expression in duck myoblasts mainly via up-regulation of mTOR

    PubMed Central

    Wang, Haohan; Li, Xinxin; Liu, Hehe; Sun, Lingli; Zhang, Rongping; Li, Liang; Wangding, Mincheng; Wang, Jiwen

    2016-01-01

    Abstract As a critical transcription factor, Six1 plays an important role in the regulation of myogenesis and muscle development. However, little is known about its regulatory mechanism associated with muscular protein synthesis. The objective of this study was to investigate the effects of overexpression ofSix1 on the expression of key protein metabolism-related genes in duck myoblasts. Through an experimental model where duck myoblasts were transfected with a pEGFP-duSix1 construct, we found that overexpression of duckSix1 could enhance cell proliferation activity and increase mRNA expression levels of key genes involved in the PI3K/Akt/mTOR signaling pathway, while the expression of FOXO1, MuRF1and MAFbx was not significantly altered, indicating thatSix1 could promote protein synthesis in myoblasts through up-regulating the expression of several related genes. Additionally, in duck myoblasts treated with LY294002 and rapamycin, the specific inhibitors ofPI3K and mTOR, respectively, the overexpression of Six1 could significantly ameliorate inhibitive effects of these inhibitors on protein synthesis. Especially, the mRNA expression levels of mTOR and S6K1 were observed to undergo a visible change, and a significant increase in protein expression of S6K1 was seen. These data suggested that Six1plays an important role in protein synthesis, which may be mainly due to activation of the mTOR signaling pathway. PMID:27007909

  10. Coagulation factor Xa drives tumor cells into apoptosis through BH3-only protein Bim up-regulation

    SciTech Connect

    Borensztajn, Keren S. . E-mail: K.S.Borensztajn@amc.uva.nl; Bijlsma, Maarten F.; Groot, Angelique P.; Brueggemann, Lois W.; Versteeg, Henri H.; Reitsma, Pieter H.; Peppelenbosch, Maikel P.; Spek, C. Arnold

    2007-07-15

    Coagulation Factor (F)Xa is a serine protease that plays a crucial role during blood coagulation by converting prothrombin into active thrombin. Recently, however, it emerged that besides this role in coagulation, FXa induces intracellular signaling leading to different cellular effects. Here, we show that coagulation factor (F)Xa drives tumor cells of epithelial origin, but not endothelial cells or monocytes, into apoptosis, whereas it even enhances fibroblast survival. FXa signals through the protease activated receptor (PAR)-1 to activate extracellular-signal regulated kinase (ERK) 1/2 and p38. This activation is associated with phosphorylation of the transcription factor CREB, and in tumor cells with up-regulation of the BH3-only pro-apoptotic protein Bim, leading to caspase-3 cleavage, the main hallmark of apoptosis. Transfection of tumor cells with dominant negative forms of CREB or siRNA for either PAR-1, Bim, ERK1 and/or p38 inhibited the pro-apoptotic effect of FXa. In fibroblasts, FXa-induced PAR-1 activation leads to down-regulation of Bim and pre-treatment with PAR-1 or Bim siRNA abolishes proliferation. We thus provide evidence that beyond its role in blood coagulation, FXa plays a key role in cellular processes in which Bim is the central player in determining cell survival.

  11. Up-regulation of Interferon-inducible protein 16 contributes to psoriasis by modulating chemokine production in keratinocytes

    PubMed Central

    Cao, Tianyu; Shao, Shuai; Li, Bing; Jin, Liang; Lei, Jie; Qiao, Hongjiang; Wang, Gang

    2016-01-01

    Psoriasis is a common chronic inflammatory skin disease characterized by epidermal hyperplasia and dermal inflammation. Keratinocyte activation is known to play a critical role in psoriasis, but the underlying mechanism remains unclear. Interferon-inducible protein 16 (IFI16), an innate immune system sensor, is reported to affect keratinocyte function. We therefore hypothesized that IFI16 promotes psoriasis by modulating keratinocyte activation. In the present study, we cinfirmed that IFI16 was overexpressed in epidermal keratinocytes of psoriasis patients. In addition, psoriasis-related cytokines, including IFN-γ, TNF-α, IL-17 and IL-22, induced IFI16 up-regulation in keratinocytes via activation of STAT3 signaling. We also observed that IFI16 activated the TBK1-NF-κB signaling, leading to the production of CXCL10 and CCL20. Importantly, knocking down p204, which is reported as the mouse orthologous of human IFI16, inhibited epidermal hyperplasia in mice with imiquimod-induced psoriasiform dermatitis. These findings indicate that IFI16 plays a critical role in the pathogenesis of psoriasis and may be a potential therapeutic target. PMID:27137868

  12. Farnesoid X receptor up-regulates expression of Lipid transfer inhibitor protein in liver cells and mice

    SciTech Connect

    Li, Liangpeng; Liu, Hong; Peng, Jiahe; Wang, Yongchao; Zhang, Yan; Dong, Jinyu; Liu, Xiaohua; Guo, Dongmei; Jiang, Yu

    2013-11-29

    Highlights: •FXR up-regulates apoF. •It binds to ER1 element. •It activates apoF gene promoter. -- Abstract: Apolipoprotein F is a component protein mainly secreted by liver and resides on several lipoprotein classes. It can inhibit lipids transfer between different lipoproteins. FXR is a member of the nuclear receptor superfamily which is also highly expressed in the liver. It modulates bile acids synthesis and lipids metabolism by transcriptional regulation. We aimed to determine whether apoF can be regulated by FXR. The FXR agonist Chenodeoxycholic acid (CDCA) and GW4064 both can activate the expression of apoF in liver cell lines and in C57/BL6 mouse liver. This is dependent on the binding of FXR to the FXR element ER1 (−2904 to −2892 bp) in the apoF gene promoter. Taken together, we have identified apoF as likely another target gene of FXR.

  13. The Up-Regulation of Ribosomal Proteins Further Regulates Protein Expression Profile in Female Schistosoma japonicum after Pairing

    PubMed Central

    Sun, Jun; Li, Chen; Wang, Suwen

    2015-01-01

    Background Pairing of Schistosoma males and females leads to and maintains female sexual maturation. However, the mechanism by which pairing facilitates sexual maturation of females is not clear. An increasing body of evidence suggests that ribosomal proteins have regulatory rather than constitutive roles in protein translation. Methodology/Principal Findings To investigate the effect of ribosome regulation on female sex maturation, Solexa and iTRAQ techniques were used to analyze the relationship between ribosomal gene or protein expression and sexual development of Schistosoma females. In the present study, considerably higher number of ribosomal genes or proteins were found to be differentially expressed in paired 23-day-old females. Moreover, mature female-specific proteins associated with egg production, such as ferritin-1 heavy chain and superoxide dismutase, were selectively highly expressed in paired females, rather than higher level of protein synthesis of all transcripts compared with those in unpaired 23-day-old females. Furthermore, other developmental stages were utilized to investigate different expression pattern of ribosomal proteins in females by analysing 18-day-old female schistosomula from single- or double-sex infections to determine the relationship between ribosomal protein expression pattern and development. Results showed that undeveloped 18-day-old females from single- and double-sex infections, as well as 23-day-old unpaired females, possessed similar ribosomal protein expression patterns, which were distinct from those in 23-day-old paired females. Conclusions/Significance Our findings reveal that the pairing of females and males triggers a specialized ribosomal protein expression profile which further regulates the protein profile for sexual maturation in Schistosoma japonicum, based on its gene expression profile. PMID:26070205

  14. A novel class of antihyperlipidemic agents with low density lipoprotein receptor up-regulation via the adaptor protein autosomal recessive hypercholesterolemia.

    PubMed

    Asano, Shigehiro; Ban, Hitoshi; Tsuboya, Norie; Uno, Shinsaku; Kino, Kouichi; Ioriya, Katsuhisa; Kitano, Masafumi; Ueno, Yoshihide

    2010-04-22

    We have previously reported compound 2 as a inhibitor of acyl-coenzyme A:cholesterol O-acyltransferase (ACAT) and up-regulator of the low density lipoprotein receptor (LDL-R) expression. In this study we focused on compound 2, a unique LDL-R up-regulator, and describe the discovery of a novel class of up-regulators of LDL-R. Replacement the methylene urea linker in compound 2 with an acylsulfonamide linker kept a potent LDL-R up-regulatory activity, and subsequent optimization work gave compound 39 as a highly potent LDL-R up-regulator (39; EC(25) = 0.047 microM). Compound 39 showed no ACAT inhibitory activity even at 1 microM. The sodium salts of compound 39 reduced plasma total and LDL cholesterol levels in a dose-dependent manner in an experimental animal model of hyperlipidemia. Moreover, we revealed in this study using RNA interference that autosomal recessive hypercholesterolemia (ARH), an adaptor protein of LDL-R, is essential for compound 39 up-regulation of LDL-R expression. PMID:20356098

  15. Chloroquine enhances TRAIL-mediated apoptosis through up-regulation of DR5 by stabilization of mRNA and protein in cancer cells

    PubMed Central

    Park, Eun Jung; Min, Kyoung-jin; Choi, Kyeong Sook; Kubatka, Peter; Kruzliak, Peter; Kim, Dong Eun; Kwon, Taeg Kyu

    2016-01-01

    Chloroquine (CQ), an anti-malarial drug, has immune-modulating activity and lysosomotropic activity. In this study, we investigated CQ sensitizes TRAIL-mediated apoptosis in human renal cancer Caki cells. Combination of CQ and TRAIL significantly induces apoptosis in human renal cancer Caki cells and various human cancer cells, but not in normal mouse kidney cells (TMCK-1) and human mesangial cells (MC). CQ up-regulates DR5 mRNA and protein expression in a dose- and time- dependent manner. Interestingly, CQ regulates DR5 expression through the increased stability in the mRNA and protein of DR5, rather than through the increased transcriptional activity of DR5. Moreover, we found that CQ decreased the expression of Cbl, an E3 ligase of DR5, and knock-down of Cbl markedly enhanced DR5 up-regulation. Other lysosomal inhibitors, including monensin and nigericin, also up-regulated DR5 and sensitized TRAIL-mediated apoptosis. Therefore, this study demonstrates that lysosomal inhibition by CQ may sensitize TRAIL-mediated apoptosis in human renal cancer Caki cells via DR5 up-regulation. PMID:26964637

  16. Chloroquine enhances TRAIL-mediated apoptosis through up-regulation of DR5 by stabilization of mRNA and protein in cancer cells.

    PubMed

    Park, Eun Jung; Min, Kyoung-jin; Choi, Kyeong Sook; Kubatka, Peter; Kruzliak, Peter; Kim, Dong Eun; Kwon, Taeg Kyu

    2016-01-01

    Chloroquine (CQ), an anti-malarial drug, has immune-modulating activity and lysosomotropic activity. In this study, we investigated CQ sensitizes TRAIL-mediated apoptosis in human renal cancer Caki cells. Combination of CQ and TRAIL significantly induces apoptosis in human renal cancer Caki cells and various human cancer cells, but not in normal mouse kidney cells (TMCK-1) and human mesangial cells (MC). CQ up-regulates DR5 mRNA and protein expression in a dose- and time- dependent manner. Interestingly, CQ regulates DR5 expression through the increased stability in the mRNA and protein of DR5, rather than through the increased transcriptional activity of DR5. Moreover, we found that CQ decreased the expression of Cbl, an E3 ligase of DR5, and knock-down of Cbl markedly enhanced DR5 up-regulation. Other lysosomal inhibitors, including monensin and nigericin, also up-regulated DR5 and sensitized TRAIL-mediated apoptosis. Therefore, this study demonstrates that lysosomal inhibition by CQ may sensitize TRAIL-mediated apoptosis in human renal cancer Caki cells via DR5 up-regulation. PMID:26964637

  17. The soy isoflavone equol may increase cancer malignancy via up-regulation of eukaryotic protein synthesis initiation factor eIF4G.

    PubMed

    de la Parra, Columba; Otero-Franqui, Elisa; Martinez-Montemayor, Michelle; Dharmawardhane, Suranganie

    2012-12-01

    Dietary soy is thought to be cancer-preventive; however, the beneficial effects of soy on established breast cancer is controversial. We recently demonstrated that dietary daidzein or combined soy isoflavones (genistein, daidzein, and glycitein) increased primary mammary tumor growth and metastasis. Cancer-promoting molecules, including eukaryotic protein synthesis initiation factors (eIF) eIF4G and eIF4E, were up-regulated in mammary tumors from mice that received dietary daidzein. Herein, we show that increased eIF expression in tumor extracts of mice after daidzein diets is associated with protein expression of mRNAs with internal ribosome entry sites (IRES) that are sensitive to eIF4E and eIF4G levels. Results with metastatic cancer cell lines show that some of the effects of daidzein in vivo can be recapitulated by the daidzein metabolite equol. In vitro, equol, but not daidzein, up-regulated eIF4G without affecting eIF4E or its regulator, 4E-binding protein (4E-BP), levels. Equol also increased metastatic cancer cell viability. Equol specifically increased the protein expression of IRES containing cell survival and proliferation-promoting molecules and up-regulated gene and protein expression of the transcription factor c-Myc. Moreover, equol increased the polysomal association of mRNAs for p 120 catenin and eIF4G. The elevated eIF4G in response to equol was not associated with eIF4E or 4E-binding protein in 5' cap co-capture assays or co-immunoprecipitations. In dual luciferase assays, IRES-dependent protein synthesis was increased by equol. Therefore, up-regulation of eIF4G by equol may result in increased translation of pro-cancer mRNAs with IRESs and, thus, promote cancer malignancy.

  18. Cyanide-induced death of dopaminergic cells is mediated by uncoupling protein-2 up-regulation and reduced Bcl-2 expression

    SciTech Connect

    Zhang, X.; Li, L.; Zhang, L.; Borowitz, J.L.; Isom, G.E.

    2009-07-01

    Cyanide is a potent inhibitor of mitochondrial oxidative metabolism and produces mitochondria-mediated death of dopaminergic neurons and sublethal intoxications that are associated with a Parkinson-like syndrome. Cyanide toxicity is enhanced when mitochondrial uncoupling is stimulated following up-regulation of uncoupling protein-2 (UCP-2). In this study, the role of a pro-survival protein, Bcl-2, in cyanide-mediated cell death was determined in a rat dopaminergic immortalized mesencephalic cell line (N27 cells). Following pharmacological up-regulation of UCP-2 by treatment with Wy14,643, cyanide reduced cellular Bcl-2 expression by increasing proteasomal degradation of the protein. The increased turnover of Bcl-2 was mediated by an increase of oxidative stress following UCP-2 up-regulation. The oxidative stress involved depletion of mitochondrial glutathione (mtGSH) and increased H{sub 2}O{sub 2} generation. Repletion of mtGSH by loading cells with glutathione ethyl ester reduced H{sub 2}O{sub 2} generation and in turn blocked the cyanide-induced decrease of Bcl-2. To determine if UCP-2 mediated the response, RNAi knock down was conducted. The RNAi decreased cyanide-induced depletion of mtGSH, reduced H{sub 2}O{sub 2} accumulation, and inhibited down-regulation of Bcl-2, thus blocking cell death. To confirm the role of Bcl-2 down-regulation in the cell death, it was shown that over-expression of Bcl-2 by cDNA transfection attenuated the enhancement of cyanide toxicity after UCP-2 up-regulation. It was concluded that UCP-2 up-regulation sensitizes cells to cyanide by increasing cellular oxidative stress, leading to an increase of Bcl-2 degradation. Then the reduced Bcl-2 levels sensitize the cells to cyanide-mediated cell death.

  19. Elevation of Highly Up-regulated in Liver Cancer (HULC) by Hepatitis B Virus X Protein Promotes Hepatoma Cell Proliferation via Down-regulating p18*

    PubMed Central

    Du, Yumei; Kong, Guangyao; You, Xiaona; Zhang, Shuai; Zhang, Tao; Gao, Yuen; Ye, Lihong; Zhang, Xiaodong

    2012-01-01

    Long noncoding RNAs (lncRNAs) play crucial roles in human cancers. It has been reported that lncRNA highly up-regulated in liver cancer (HULC) is dramatically up-regulated in hepatocellular carcinoma (HCC). Hepatitis B virus X protein (HBx) contributes importantly to the development of HCC. However, the function of HULC in HCC mediated by HBx remains unclear. Here, we report that HULC is involved in HBx-mediated hepatocarcinogenesis. We found that the expression levels of HULC were positively correlated with those of HBx in clinical HCC tissues. Moreover, we revealed that HBx up-regulated HULC in human immortalized normal liver L-O2 cells and hepatoma HepG2 cells. Luciferase reporter gene assay and chromatin immunoprecipitation (ChIP) assay showed that HBx activated the HULC promoter via cAMP-responsive element-binding protein. We further demonstrated that HULC promoted cell proliferation by methyl thiazolyl tetrazolium, 5-ethynyl-2′-deoxyuridine, colony formation assay, and tumorigenicity assay. Next, we hypothesized that HULC might function through regulating a tumor suppressor gene p18 located near HULC in the same chromosome. We found that the mRNA levels of p18 were inversely correlated with those of HULC in the above clinical HCC specimens. Then, we validated that HULC down-regulated p18, which was involved in the HULC-enhanced cell proliferation in vitro and in vivo. Furthermore, we observed that knockdown of HULC could abolish the HBx-enhanced cell proliferation through up-regulating p18. Thus, we conclude that the up-regulated HULC by HBx promotes proliferation of hepatoma cells through suppressing p18. This finding provides new insight into the roles of lncRNAs in HBx-related hepatocarcinogenesis. PMID:22685290

  20. Activation of stress-activated MAP protein kinases up-regulates expression of transgenes driven by the cytomegalovirus immediate/early promoter.

    PubMed Central

    Bruening, W; Giasson, B; Mushynski, W; Durham, H D

    1998-01-01

    The immediate/early promoter/enhancer of cytomegalovirus (CMV promoter) is one of the most commonly used promoters for expression of transgenes in eukaryotic cells. In practice, the CMV promoter is often thought of as a constitutively active unregulated promoter. However, we have observed that transcription from the CMV promoter can be up-regulated by a variety of environmental stresses. Many forms of cellular stress stimulate MAP kinase signalling pathways, resulting in activation of stress-activated protein kinases [SAPKs, also called Jun N-terminal kinases (JNKs)] and p38 kinases. We have found that the same conditions that lead to activation of SAPK/JNKs and p38 kinases can also dramatically increase expression from the CMV promoter. Inhibitors of p38 kinases abolished basal transcription from the CMV promoter and completely blocked stress-induced up-regulation of the CMV promoter. Overexpression of a dominant negative JNK kinase had no effect on basal transcription, but significantly reduced up-regulation caused by stress. These results have grave implications for use of the CMV promoter. If the CMV promoter can be up-regulated by cellular stresses, inadvertent activation of the stress kinase pathways may complicate, if not invalidate, the interpretation of a wide range of experiments. PMID:9421504

  1. An early ethylene up-regulated gene encoding a calmodulin-binding protein involved in plant senescence and death

    NASA Technical Reports Server (NTRS)

    Yang, T.; Poovaiah, B. W.

    2000-01-01

    35S-Labeled calmodulin (CaM) was used to screen a tobacco anther cDNA library. A positive clone (NtER1) with high homology to an early ethylene-up-regulated gene (ER66) in tomato, and an Arabidopsis homolog was isolated and characterized. Based on the helical wheel projection, a 25-mer peptide corresponding to the predicted CaM-binding region of NtER1 (amino acids 796-820) was synthesized. The gel-mobility shift assay showed that the peptide formed a stable complex with CaM only in the presence of Ca(2+). CaM binds to NtER1 with high affinity (K(d) approximately 12 nm) in a calcium-dependent manner. Tobacco flowers at different stages of development were treated with ethylene or with 1-methylcyclopropene for 2 h before treating with ethylene. Northern analysis showed that the NtER1 was rapidly induced after 15 min of exposure to ethylene. However, the 2-h 1-methylcyclopropene treatment totally blocked NtER1 expression in flowers at all stages of development, suggesting that NtER1 is an early ethylene-up-regulated gene. The senescing leaves and petals had significantly increased NtER1 induction as compared with young leaves and petals, implying that NtER1 is developmentally regulated and acts as a trigger for senescence and death. This is the first documented evidence for the involvement of Ca(2+)/CaM-mediated signaling in ethylene action.

  2. EsMlp, a muscle-LIM protein gene, is up-regulated during cold exposure in the freeze-avoiding larvae of Epiblema scudderiana.

    PubMed

    Bilgen, T; English, T E; McMullen, D C; Storey, K B

    2001-08-01

    Screening of a cDNA library identified transcripts that were up-regulated by cold (4 or -20 degrees C) exposure in larvae of the freeze-avoiding goldenrod gall moth, Epiblema scudderiana. One clone contained a full-length open reading frame encoding a protein of 94 amino acids. The gene product, with 79.1% of residues identical with the Drosophila LIM protein Mlp60A, was named EsMlp and contained a single LIM domain and consensus sequences characteristic of a LIM protein. Transcript levels rose approx twofold when larvae were shifted from 4 to -20 degrees C and approx threefold over the midwinter months compared with larvae sampled in October or April. EsMlp expression was high in larval head (possibly due to expression in pharyngeal muscles) and body wall but was not detected in fat body. Immunoblotting revealed a three- to fourfold increase in EsMlp protein in midwinter larvae (January-February) compared with November-collected animals and a further rise to eightfold higher than November values in larvae collected in April. Cold up-regulation of EsMlp and the pattern of EsMlp levels in the larvae suggest possible roles for the protein, such as in muscle maintenance over the winter or as a preparative function that could facilitate the rapid resumption of development and metamorphosis when environmental temperatures rise in the spring.

  3. Histone hyperacetylation up-regulates protein kinase Cδ in dopaminergic neurons to induce cell death: relevance to epigenetic mechanisms of neurodegeneration in Parkinson disease.

    PubMed

    Jin, Huajun; Kanthasamy, Arthi; Harischandra, Dilshan S; Kondru, Naveen; Ghosh, Anamitra; Panicker, Nikhil; Anantharam, Vellareddy; Rana, Ajay; Kanthasamy, Anumantha G

    2014-12-12

    The oxidative stress-sensitive protein kinase Cδ (PKCδ) has been implicated in dopaminergic neuronal cell death. However, little is known about the epigenetic mechanisms regulating PKCδ expression in neurons. Here, we report a novel mechanism by which the PKCδ gene can be regulated by histone acetylation. Treatment with histone deacetylase (HDAC) inhibitor sodium butyrate (NaBu) induced PKCδ expression in cultured neurons, brain slices, and animal models. Several other HDAC inhibitors also mimicked NaBu. The chromatin immunoprecipitation analysis revealed that hyperacetylation of histone H4 by NaBu is associated with the PKCδ promoter. Deletion analysis of the PKCδ promoter mapped the NaBu-responsive element to an 81-bp minimal promoter region. Detailed mutagenesis studies within this region revealed that four GC boxes conferred hyperacetylation-induced PKCδ promoter activation. Cotransfection experiments and Sp inhibitor studies demonstrated that Sp1, Sp3, and Sp4 regulated NaBu-induced PKCδ up-regulation. However, NaBu did not alter the DNA binding activities of Sp proteins or their expression. Interestingly, a one-hybrid analysis revealed that NaBu enhanced transcriptional activity of Sp1/Sp3. Overexpression of the p300/cAMP-response element-binding protein-binding protein (CBP) potentiated the NaBu-mediated transactivation potential of Sp1/Sp3, but expressing several HDACs attenuated this effect, suggesting that p300/CBP and HDACs act as coactivators or corepressors in histone acetylation-induced PKCδ up-regulation. Finally, using genetic and pharmacological approaches, we showed that NaBu up-regulation of PKCδ sensitizes neurons to cell death in a human dopaminergic cell model and brain slice cultures. Together, these results indicate that histone acetylation regulates PKCδ expression to augment nigrostriatal dopaminergic cell death, which could contribute to the progressive neuropathogenesis of Parkinson disease.

  4. The membrane-associated progesterone-binding protein 25-Dx: expression, cellular localization and up-regulation after brain and spinal cord injuries.

    PubMed

    Guennoun, R; Meffre, D; Labombarda, F; Gonzalez, S L; Gonzalez Deniselle, M C; Stein, D G; De Nicola, A F; Schumacher, M

    2008-03-01

    Progesterone has neuroprotective effects in the injured and diseased spinal cord and after traumatic brain injury (TBI). In addition to intracellular progesterone receptors (PR), membrane-binding sites of progesterone may be involved in neuroprotection. A first putative membrane receptor of progesterone, distinct from the classical intracellular PR isoforms, with a single membrane-spanning domain, has been cloned from porcine liver. Homologous proteins were cloned in rats (25-Dx), mice (PGRMC1) and humans (Hpr.6). We will refer to this progesterone-binding protein as 25-Dx. The distribution and regulation of 25-Dx in the nervous system may provide some clues to its functions. In spinal cord, 25-Dx is localized in cell membranes of dorsal horn neurons and ependymal cells lining the central canal. A role of 25-Dx in mediating the protective effects of progesterone in the spinal cord is supported by the observation that its mRNA and protein are up-regulated by progesterone in dorsal horn of the injured spinal cord. In contrast, the classical intracellular PRs were down-regulated under these conditions. In brain, 25-Dx is particularly abundant in the hypothalamic area, circumventricular organs, ependymal cells of the ventricular walls, and the meninges. Interestingly, it is co-expressed with vasopressin in neurons of the paraventricular, supraoptic and retrochiasmatic nuclei. In response to TBI, 25-Dx expression is up-regulated in neurons and induced in astrocytes. The expression of 25-Dx in structures involved in cerebrospinal fluid production and osmoregulation, and its up-regulation after brain damage, point to a potentially important role of this progesterone-binding protein in the maintenance of water homeostasis after TBI. Our observations suggest that progesterone's actions may involve different signaling mechanisms depending on the pathophysiological context, and that 25-Dx may be involved in the neuroprotective effect of progesterone in the injured brain and

  5. Protein cryoprotective activity of a cytosolic small heat shock protein that accumulates constitutively in chestnut stems and is up-regulated by low and high temperatures.

    PubMed

    Lopez-Matas, Maria-Angeles; Nuñez, Paulina; Soto, Alvaro; Allona, Isabel; Casado, Rosa; Collada, Carmen; Guevara, Maria-Angeles; Aragoncillo, Cipriano; Gomez, Luis

    2004-04-01

    Heat shock, and other stresses that cause protein misfolding and aggregation, trigger the accumulation of heat shock proteins (HSPs) in virtually all organisms. Among the HSPs of higher plants, those belonging to the small HSP (sHSP) family remain the least characterized in functional terms. We analyzed the occurrence of sHSPs in vegetative organs of Castanea sativa (sweet chestnut), a temperate woody species that exhibits remarkable freezing tolerance. A constitutive sHSP subject to seasonal periodic changes of abundance was immunodetected in stems. This protein was identified by matrix-assisted laser-desorption ionization time of flight mass spectrometry and internal peptide sequencing as CsHSP17.5, a cytosolic class I sHSP previously described in cotyledons. Expression of the corresponding gene in stems was confirmed through cDNA cloning and reverse transcription-PCR. Stem protein and mRNA profiles indicated that CsHSP17.5 is significantly up-regulated in spring and fall, reaching maximal levels in late summer and, especially, in winter. In addition, cold exposure was found to quickly activate shsp gene expression in both stems and roots of chestnut seedlings kept in growth chambers. Our main finding is that purified CsHSP17.5 is very effective in protecting the cold-labile enzyme lactate dehydrogenase from freeze-induced inactivation (on a molar basis, CsHSP17.5 is about 400 times more effective as cryoprotectant than hen egg-white lysozyme). Consistent with these observations, repeated freezing/thawing did not affect appreciably the chaperone activity of diluted CsHSP17.5 nor its ability to form dodecameric complexes in vitro. Taken together, these results substantiate the hypothesis that sHSPs can play relevant roles in the acquisition of freezing tolerance.

  6. A LEA 4 protein up-regulated by ABA is involved in drought response in maize roots.

    PubMed

    Zamora-Briseño, Jesús Alejandro; de Jiménez, Estela Sánchez

    2016-04-01

    Late embryogenesis abundant (LEA) proteins are hydrophilic proteins that accumulate to high concentrations during the late stages of seeds development, which are integral to desiccation tolerance. LEA proteins also play a protective role under other abiotic stresses. We analyzed in silico a maize protein predicted to be highly hydrophilic and intrinsically disordered. This prediction was experimentally corroborated by solubility assays under denaturing conditions. Based on its amino acid sequence, we propose that this protein belongs to group four of the LEA proteins. The accumulation pattern of this protein was similar to that of dehydrins during the desiccation process that takes place during seed development. This protein was induced by exogenous abscisic acid in immature embryos, but during imbibition was down-regulated by gibberellins. It was also induced in maize roots under osmotic stress. So far, this is the first member of the LEA proteins belonging to group four to be characterized in maize, and it plays a role in the response to osmotic stress. PMID:26922182

  7. G protein-coupled receptor 30 expression is up-regulated by EGF and TGF alpha in estrogen receptor alpha-positive cancer cells.

    PubMed

    Vivacqua, Adele; Lappano, Rosamaria; De Marco, Paola; Sisci, Diego; Aquila, Saveria; De Amicis, Francesca; Fuqua, Suzanne A W; Andò, Sebastiano; Maggiolini, Marcello

    2009-11-01

    In the present study, we evaluated the regulation of G protein-coupled receptor (GPR)30 expression in estrogen receptor (ER)-positive endometrial, ovarian, and estrogen-sensitive, as well as tamoxifen-resistant breast cancer cells. We demonstrate that epidermal growth factor (EGF) and TGF alpha transactivate the GPR30 promoter and accordingly up-regulate GPR30 mRNA and protein levels only in endometrial and tamoxifen-resistant breast cancer cells. These effects exerted by EGF and TGF alpha were dependent on EGF receptor (EGFR) expression and activation and involved phosphorylation of the Tyr(1045) and Tyr(1173) EGFR sites. Using gene-silencing experiments and specific pharmacological inhibitors, we have ascertained that EGF and TGF alpha induce GPR30 expression through the EGFR/ERK transduction pathway, and the recruitment of c-fos to the activator protein-1 site located within GPR30 promoter sequence. Interestingly, we show that functional cross talk of GPR30 with both activated EGFR and ER alpha relies on a physical interaction among these receptors, further extending the potential of estrogen to trigger a complex stimulatory signaling network in hormone-sensitive tumors. Given that EGFR/HER2 overexpression is associated with tamoxifen resistance, our data may suggest that ligand-activated EGFR could contribute to the failure of tamoxifen therapy also by up-regulating GPR30, which in turn could facilitates the action of estrogen. In addition, important for resistance is the ability of tamoxifen to bind to and activate GPR30, the expression of which is up-regulated by EGFR activation. Our results emphasize the need for new endocrine agents able to block widespread actions of estrogen without exerting any stimulatory activity on transduction pathways shared by the steroid and growth factor-signaling networks.

  8. The freshwater Amazonian stingray, Potamotrygon motoro, up-regulates glutamine synthetase activity and protein abundance, and accumulates glutamine when exposed to brackish (15 per thousand) water.

    PubMed

    Ip, Y K; Loong, A M; Ching, B; Tham, G H Y; Wong, W P; Chew, S F

    2009-12-01

    This study aimed to examine whether the stenohaline freshwater stingray, Potamotrygon motoro, which lacks a functional ornithine-urea cycle, would up-regulate glutamine synthetase (GS) activity and protein abundance, and accumulate glutamine during a progressive transfer from freshwater to brackish (15 per thousand) water with daily feeding. Our results revealed that, similar to other freshwater teleosts, P. motoro performed hyperosmotic regulation, with very low urea concentrations in plasma and tissues, in freshwater. In 15 per thousand water, it was non-ureotelic and non-ureoosmotic, acting mainly as an osmoconformer with its plasma osmolality, [Na+] and [Cl-] comparable to those of the external medium. There were significant increases in the content of several free amino acids (FAAs), including glutamate, glutamine and glycine, in muscle and liver, but not in plasma, indicating that FAAs could contribute in part to cell volume regulation. Furthermore, exposure of P. motoro to 15 per thousand water led to up-regulation of GS activity and protein abundance in both liver and muscle. Thus, our results indicate for the first time that, despite the inability to synthesize urea and the lack of functional carbamoyl phosphate synthetase III (CPS III) which uses glutamine as a substrate, P. motoro retained the capacity to up-regulate the activity and protein expression of GS in response to salinity stress. Potamotrygon motoro was not nitrogen (N) limited when exposed to 15 per thousand water with feeding, and there were no significant changes in the amination and deamination activities of hepatic glutamate dehydrogenase. In contrast, P. motoro became N limited when exposed to 10 per thousand water with fasting and could not survive well in 15 per thousand water without food.

  9. A Proteomic Approach for the Identification of Up-Regulated Proteins Involved in the Metabolic Process of the Leiomyoma

    PubMed Central

    Ura, Blendi; Scrimin, Federica; Arrigoni, Giorgio; Franchin, Cinzia; Monasta, Lorenzo; Ricci, Giuseppe

    2016-01-01

    Uterine leiomyoma is the most common benign smooth muscle cell tumor of the uterus. Proteomics is a powerful tool for the analysis of complex mixtures of proteins. In our study, we focused on proteins that were upregulated in the leiomyoma compared to the myometrium. Paired samples of eight leiomyomas and adjacent myometrium were obtained and submitted to two-dimensional gel electrophoresis (2-DE) and mass spectrometry for protein identification and to Western blotting for 2-DE data validation. The comparison between the patterns revealed 24 significantly upregulated (p < 0.05) protein spots, 12 of which were found to be associated with the metabolic processes of the leiomyoma and not with the normal myometrium. The overexpression of seven proteins involved in the metabolic processes of the leiomyoma was further validated by Western blotting and 2D Western blotting. Four of these proteins have never been associated with the leiomyoma before. The 2-DE approach coupled with mass spectrometry, which is among the methods of choice for comparative proteomic studies, identified a number of proteins overexpressed in the leiomyoma and involved in several biological processes, including metabolic processes. A better understanding of the mechanism underlying the overexpression of these proteins may be important for therapeutic purposes. PMID:27070597

  10. Up-regulated 14-3-3β and 14-3-3ζ proteins in prefrontal cortex of subjects with schizophrenia: effect of psychotropic treatment.

    PubMed

    Rivero, Guadalupe; Gabilondo, Ane M; García-Sevilla, Jesús A; La Harpe, Romano; Morentín, Benito; Meana, J Javier

    2015-02-01

    14-3-3 is a family of conserved regulatory proteins that bind to a multitude of functionally diverse signalling proteins. Various genetic studies and gene expression and proteomic analyses have involved 14-3-3 proteins in schizophrenia (SZ). On the other hand, studies about the status of these proteins in major depressive disorder (MD) are still missing. Immunoreactivity values of cytosolic 14-3-3β and 14-3-3ζ proteins were evaluated by Western blot in prefrontal cortex (PFC) of subjects with schizophrenia (SZ; n=22), subjects with major depressive disorder (MD; n=21) and age-, gender- and postmortem delay-matched control subjects (n=52). The modulation of 14-3-3β and 14-3-3ζ proteins by psychotropic medication was also assessed. The analysis of both proteins in SZ subjects with respect to matched control subjects showed increased 14-3-3β (Δ=33±10%, p<0.05) and 14-3-3ζ (Δ=29±6%, p<0.05) immunoreactivity in antipsychotic-free but not in antipsychotic-treated SZ subjects. Immunoreactivity values of 14-3-3β and 14-3-3ζ were not altered in MD subjects. These results show the specific up-regulation of 14-3-3β and 14-3-3ζ proteins in PFC of SZ subjects and suggest a possible down-regulation of both proteins by antipsychotic treatment.

  11. Up-regulated 14-3-3β and 14-3-3ζ proteins in prefrontal cortex of subjects with schizophrenia: effect of psychotropic treatment.

    PubMed

    Rivero, Guadalupe; Gabilondo, Ane M; García-Sevilla, Jesús A; La Harpe, Romano; Morentín, Benito; Meana, J Javier

    2015-02-01

    14-3-3 is a family of conserved regulatory proteins that bind to a multitude of functionally diverse signalling proteins. Various genetic studies and gene expression and proteomic analyses have involved 14-3-3 proteins in schizophrenia (SZ). On the other hand, studies about the status of these proteins in major depressive disorder (MD) are still missing. Immunoreactivity values of cytosolic 14-3-3β and 14-3-3ζ proteins were evaluated by Western blot in prefrontal cortex (PFC) of subjects with schizophrenia (SZ; n=22), subjects with major depressive disorder (MD; n=21) and age-, gender- and postmortem delay-matched control subjects (n=52). The modulation of 14-3-3β and 14-3-3ζ proteins by psychotropic medication was also assessed. The analysis of both proteins in SZ subjects with respect to matched control subjects showed increased 14-3-3β (Δ=33±10%, p<0.05) and 14-3-3ζ (Δ=29±6%, p<0.05) immunoreactivity in antipsychotic-free but not in antipsychotic-treated SZ subjects. Immunoreactivity values of 14-3-3β and 14-3-3ζ were not altered in MD subjects. These results show the specific up-regulation of 14-3-3β and 14-3-3ζ proteins in PFC of SZ subjects and suggest a possible down-regulation of both proteins by antipsychotic treatment. PMID:25549848

  12. Antagonist-induced micro-opioid receptor up-regulation decreases G-protein receptor kinase-2 and dynamin-2 abundance in mouse spinal cord.

    PubMed

    Patel, Minesh; Gomes, Benedict; Patel, Chintan; Yoburn, Byron C

    2002-06-20

    Chronic treatment with opioid receptor antagonists has been shown to increase the density of micro-, delta- and kappa-opioid receptors in cell culture and in the intact animal. Although opioid receptor antagonist-induced up-regulation is a robust phenomenon, the mechanisms responsible for the increase in receptor density remain unclear. In the present study, changes in a kinase and a GTPase that have been implicated in G-protein-coupled receptor regulation were examined following opioid receptor antagonist treatment. Mice were implanted s.c. with a naltrexone pellet or placebo pellet. On the eighth day following implantation, spinal cord was removed and G-protein receptor kinase-2 (GRK-2) and dynamin-2 abundance were determined using a quantitative immunoblot approach. Changes in micro-opioid receptor density were also determined. Naltrexone treatment produced a significant (145%) increase in micro-opioid receptor density. Naltrexone treatment was associated with a significant 36% decrease in GRK-2 and 30% decrease in dynamin-2 abundance in spinal cord. These data raise the possibility that opioid receptor antagonist-induced micro-opioid receptor up-regulation in the intact animal may be due to a reduction in constitutive internalization of opioid receptors.

  13. E-cadherin and alpha-, beta-, and gamma-catenin protein expression is up-regulated in ovarian carcinoma cells in serous effusions.

    PubMed

    Davidson, B; Berner, A; Nesland, J M; Risberg, B; Berner, H S; Tropè, C G; Kristensen, G B; Bryne, M; Ann Florenes, V

    2000-12-01

    The aims of this study were firstly, to investigate the expression of E-cadherin complex proteins in ovarian carcinoma cells in serous effusions and in primary and metastatic lesions; and secondly to study the value of these four proteins and calretinin, a mesothelial marker, in the differential diagnosis of ovarian carcinoma cells from reactive mesothelial cells in effusions. Sixty-seven malignant effusions and 97 corresponding primary (n=36) and metastatic (n=61) lesions were immunohistochemically stained for E-cadherin and alpha-, beta-, and gamma-catenin. Staining extent and intensity were scored. Effusion specimens were additionally analysed for calretinin immunoreactivity. Membrane immunoreactivity for E-cadherin and alpha-, beta-, and gamma-catenin was detected on carcinoma cells in the majority of the effusions, but rarely on reactive mesothelial cells (p<0.001 for all markers). Calretinin immunoreactivity was confined to mesothelial cells (p<0.001). An association was seen between E-cadherin and alpha-catenin expression, in both effusions and solid tumours, and for beta-catenin in solid tumours (range p<0. 001 to p=0.014). Up-regulation of all four cadherin complex proteins was seen in carcinoma cells in effusions, when compared with corresponding primary tumours (range p<0.001 to p=0.028). As with effusions, metastatic lesions showed up-regulation of alpha-, beta-, and gamma-catenin when compared with primary carcinomas (p=0.002-0. 015). Carcinoma cells in effusions showed in addition elevated levels of E-cadherin when compared with metastatic lesions (p<0.001). Staining results in effusions showed no association with effusion site, tumour type or histological grade. Immunoblotting on 29 malignant effusions confirmed the presence of all four proteins in the majority of samples and co-precipitation of E-cadherin and beta-catenin was seen in ten specimens examined. E-cadherin complex proteins are widely expressed in ovarian carcinoma cells. Together with

  14. Cell-penetrable mouse forkhead box protein 3 alleviates experimental arthritis in mice by up-regulating regulatory T cells.

    PubMed

    Liu, Xia; Ji, Baoju; Sun, Mengyi; Wu, Weijiang; Huang, Lili; Sun, Aihua; Zong, Yangyong; Xia, Sheng; Shi, Liyun; Qian, Hui; Xu, Wenrong; Shao, Qixiang

    2015-07-01

    Regulatory T cells (T(regs)) have potential applications in clinical disease therapy, such as autoimmune diseases and transplant rejection. However, their numbers are limited. Forkhead box protein 3 (FoxP3) is a key transcription factor that controls T(reg) development and function. Here, we generated a cell-permeable fusion protein, protein transduction domain (PTD)-conjugated mouse FoxP3 protein (PTD-mFoxP3), and evaluated whether PTD-mFoxp3 can alleviate rheumatoid arthritis (RA) in the collagen-induced arthritis (CIA) mouse model. As expected, PTD-mFoxP3 was transduced into cells effectively, and inhibited T cell activation and attenuated the cell proliferation. It decreased interleukin (IL) 2 and interferon (IFN)-γ expression, and increased IL-10 expression in activated CD4(+)CD25(-) T cells. PTD-mFoxP3-transduced CD4(+)CD25(-) T cells attenuated proliferation of activated CD4(+)CD25(-) T cells. In addition, PTD-mFoxP3 blocked the Th17 differentiation programme in vitro and down-regulated IL-17 production from T cells by modulating induction and levels of retinoid-related orphan receptor gamma t (RORγt). Intra-articular delivery of PTD-mFoxP3 delayed disease incidence remarkably and alleviated autoimmune symptoms of CIA mice. Moreover, protective effects of PTD-mFoxP3 were associated with regulating the balance of T helper type 17 (Th17) and T(regs). These results suggest that PTD-mFoxP3 may be a candidate for RA therapy. PMID:25809415

  15. Cell-penetrable mouse forkhead box protein 3 alleviates experimental arthritis in mice by up-regulating regulatory T cells.

    PubMed

    Liu, Xia; Ji, Baoju; Sun, Mengyi; Wu, Weijiang; Huang, Lili; Sun, Aihua; Zong, Yangyong; Xia, Sheng; Shi, Liyun; Qian, Hui; Xu, Wenrong; Shao, Qixiang

    2015-07-01

    Regulatory T cells (T(regs)) have potential applications in clinical disease therapy, such as autoimmune diseases and transplant rejection. However, their numbers are limited. Forkhead box protein 3 (FoxP3) is a key transcription factor that controls T(reg) development and function. Here, we generated a cell-permeable fusion protein, protein transduction domain (PTD)-conjugated mouse FoxP3 protein (PTD-mFoxP3), and evaluated whether PTD-mFoxp3 can alleviate rheumatoid arthritis (RA) in the collagen-induced arthritis (CIA) mouse model. As expected, PTD-mFoxP3 was transduced into cells effectively, and inhibited T cell activation and attenuated the cell proliferation. It decreased interleukin (IL) 2 and interferon (IFN)-γ expression, and increased IL-10 expression in activated CD4(+)CD25(-) T cells. PTD-mFoxP3-transduced CD4(+)CD25(-) T cells attenuated proliferation of activated CD4(+)CD25(-) T cells. In addition, PTD-mFoxP3 blocked the Th17 differentiation programme in vitro and down-regulated IL-17 production from T cells by modulating induction and levels of retinoid-related orphan receptor gamma t (RORγt). Intra-articular delivery of PTD-mFoxP3 delayed disease incidence remarkably and alleviated autoimmune symptoms of CIA mice. Moreover, protective effects of PTD-mFoxP3 were associated with regulating the balance of T helper type 17 (Th17) and T(regs). These results suggest that PTD-mFoxP3 may be a candidate for RA therapy.

  16. Aspirin influences megakaryocytic gene expression leading to up-regulation of multidrug resistance protein-4 in human platelets

    PubMed Central

    Massimi, Isabella; Guerriero, Raffaella; Lotti, Lavinia Vittoria; Lulli, Valentina; Borgognone, Alessandra; Romani, Federico; Barillà, Francesco; Gaudio, Carlo; Gabbianelli, Marco; Frati, Luigi; Pulcinelli, Fabio M

    2014-01-01

    Aim The aim of the study was to investigate whether human megakaryocytic cells have an adaptive response to aspirin treatment, leading to an enhancement of multidrug resistance protein-4 (MRP4) expression in circulating platelets responsible for a reduced aspirin action. We recently found that platelet MRP4 overexpression has a role in reducing aspirin action in patients after by-pass surgery. Aspirin enhances MRP4-mRNA levels in rat liver and drug administration transcriptionally regulates MRP4 gene expression through peroxisome proliferator-activated receptor-α (PPARα). Methods The effects induced by aspirin or PPARα agonist (WY14643) on MRP4 modulation were evaluated in vitro in a human megakaryoblastic DAMI cell line, in megakaryocytes (MKs) and in platelets obtained from human haematopoietic progenitor cell (HPC) cultures, and in vivo platelets obtained from aspirin treated healthy volunteers (HV). Results In DAMI cells, aspirin and WY14643 treatment induced a significant increase in MRP4 and PPARα expression. In human MKs grown in the presence of either aspirin or WY14643, MRP4 and PPARα-mRNA were higher than in control cultures and derived platelets showed an enhancement in MRP4 protein expression. The ability of aspirin to modulate MRP4 expression in MKs and to transfer it to platelets was also confirmed in vivo. In fact, we found the highest MRP4 mRNA and protein expression in platelets obtained from HV after 15 days' aspirin treatment. Conclusions The present study provides evidence, for the first time, that aspirin treatment affects the platelet protein pattern through MK genomic modulation. This work represents an innovative and attractive approach, useful both to identify patients less sensitive to aspirin and to improve pharmacological treatment in cardiovascular high-risk patients. PMID:24902864

  17. Cultured lymphocytes from autistic children and non-autistic siblings up-regulate heat shock protein RNA in response to thimerosal challenge.

    PubMed

    Walker, Stephen J; Segal, Jeffrey; Aschner, Michael

    2006-09-01

    There are reports suggesting that some autistic children are unable to mount an adequate response following exposure to environmental toxins. This potential deficit, coupled with the similarity in clinical presentations of autism and some heavy metal toxicities, has led to the suggestion that heavy metal poisoning might play a role in the etiology of autism in uniquely susceptible individuals. Thimerosal, an anti-microbial preservative previously added routinely to childhood multi-dose vaccines, is composed of 49.6% ethyl mercury. Based on the levels of this toxin that children receive through routine immunization schedules in the first years of life, it has been postulated that thimerosal may be a potential triggering mechanism contributing to autism in susceptible individuals. One potential risk factor in these individuals may be an inability to adequately up-regulate metallothionein (MT) biosynthesis in response to presentation of a heavy metal challenge. To investigate this hypothesis, cultured lymphocytes (obtained from the Autism Genetic Resource Exchange, AGRE) from autistic children and non-autistic siblings were challenged with either 10 microM ethyl mercury, 150 microM zinc, or fresh media (control). Following the challenge, total RNA was extracted and used to query "whole genome" DNA microarrays. Cultured lymphocytes challenged with zinc responded with an impressive up-regulation of MT transcripts (at least nine different MTs were over-expressed) while cells challenged with thimerosal responded by up-regulating numerous heat shock protein transcripts, but not MTs. Although there were no apparent differences between autistic and non-autistic sibling responses in this very small sampling group, the differences in expression profiles between those cells treated with zinc versus thimerosal were dramatic. Determining cellular response, at the level of gene expression, has important implications for the understanding and treatment of conditions that result

  18. Over-expression of the cercosporin facilitator protein, CFP, in Cercospora kikuchii up-regulates production and secretion of cercosporin.

    PubMed

    Upchurch, R G; Rose, M S; Eweida, M

    2001-10-16

    CFP (cercosporin facilitator protein), a light-regulated gene from the soybean fungal pathogen Cercospora kikuchii, encodes the putative major facilitator transporter of the fungal polyketide cercosporin. Gene disruption of CFP in C. kikuchii strain Gus-3 resulted in dramatically reduced cercosporin production and virulence, and increased sensitivity to the toxin. Two C. kikuchii transformant strains (10-1 and 10-11) that over-produce cercosporin were recovered from the complementation of CFP gene-disrupted strain Gus-3. Southern analysis revealed that these strains contained multiple genomic copies of CFP and over-expressed CFP transcript and protein. Although 10-1 and 10-11 produce and secrete significantly elevated levels of cercosporin, they exhibit wild-type resistance to cercosporin, and maintain a wild-type pattern of light-regulated toxin accumulation. Restoration of wild-type cercosporin resistance in 10-1 and 10-11 suggests that CFP does contribute substantially to cercosporin resistance via toxin secretion. The three-fold increase in toxin accumulation, predominantly associated with the mycelium fraction of these CFP multi-copy strains, suggests that CFP may also have a significant, but unknown, role in regulating toxin production.

  19. Farnesoid X receptor up-regulates expression of lipid transfer inhibitor protein in liver cells and mice.

    PubMed

    Li, Liangpeng; Liu, Hong; Peng, Jiahe; Wang, Yongchao; Zhang, Yan; Dong, Jinyu; Liu, Xiaohua; Guo, Dongmei; Jiang, Yu

    2013-11-29

    Apolipoprotein F is a component protein mainly secreted by liver and resides on several lipoprotein classes. It can inhibit lipids transfer between different lipoproteins. FXR is a member of the nuclear receptor superfamily which is also highly expressed in the liver. It modulates bile acids synthesis and lipids metabolism by transcriptional regulation. We aimed to determine whether apoF can be regulated by FXR. The FXR agonist Chenodeoxycholic acid (CDCA) and GW4064 both can activate the expression of apoF in liver cell lines and in C57/BL6 mouse liver. This is dependent on the binding of FXR to the FXR element ER1 (-2904 to -2892 bp) in the apoF gene promoter. Taken together, we have identified apoF as likely another target gene of FXR.

  20. Yes-Associated Protein is up-regulated by mechanical overload and is sufficient to induce skeletal muscle hypertrophy.

    PubMed

    Goodman, Craig A; Dietz, Jason M; Jacobs, Brittany L; McNally, Rachel M; You, Jae-Sung; Hornberger, Troy A

    2015-06-01

    Mechanically-induced skeletal muscle growth is regulated by mammalian/mechanistic target of rapamycin complex 1 (mTORC1). Yes-Associated Protein (YAP) is a mechanically-sensitive, and growth-related, transcriptional co-activator that can regulate mTORC1. Here we show that, in skeletal muscle, mechanical overload promotes an increase in YAP expression; however, the time course of YAP expression is markedly different from that of mTORC1 activation. We also show that the overexpression of YAP induces hypertrophy via an mTORC1-independent mechanism. Finally, we provide preliminary evidence of possible mediators of YAP-induced hypertrophy (e.g. increased MyoD and c-Myc expression, and decreased Smad2/3 activity and muscle ring finger 1 (MuRF1) expression).

  1. Involvement of YODA and mitogen activated protein kinase 6 in Arabidopsis post-embryogenic root development through auxin up-regulation and cell division plane orientation

    PubMed Central

    Smékalová, Veronika; Luptovčiak, Ivan; Komis, George; Šamajová, Olga; Ovečka, Miroslav; Doskočilová, Anna; Takáč, Tomáš; Vadovič, Pavol; Novák, Ondřej; Pechan, Tibor; Ziemann, Anja; Košútová, Petra; Šamaj, Jozef

    2015-01-01

    Summary The role of YODA MITOGEN ACTIVATED PROTEIN KINASE KINASE KINASE 4 (MAPKKK4) upstream of MITOGEN ACTIVATED PROTEIN KINASE 6 (MPK6) was studied during post-embryonic root development of Arabidopsis thaliana. Loss- and gain-of-function mutants of YODA (yda1 and ΔNyda1) were characterized in terms of root patterning, endogenous auxin content and global proteomes.We surveyed morphological and cellular phenotypes of yda1 and ΔNyda1 mutants suggesting possible involvement of auxin. Endogenous indole-3-acetic acid (IAA) levels were up-regulated in both mutants. Proteomic analysis revealed up-regulation of auxin biosynthetic enzymes tryptophan synthase and nitrilases in these mutants. The expression, abundance and phosphorylation of MPK3, MPK6 and MICROTUBULE ASSOCIATED PROTEIN 65–1 (MAP65-1) were characterized by quantitative polymerase chain reaction (PCR) and western blot analyses and interactions between MAP65-1, microtubules and MPK6 were resolved by quantitative co-localization studies and co-immunoprecipitations.yda1 and ΔNyda1 mutants showed disoriented cell divisions in primary and lateral roots, abortive cytokinesis, and differential subcellular localization of MPK6 and MAP65-1. They also showed deregulated expression of TANGLED1 (TAN1), PHRAGMOPLAST ORIENTING KINESIN 1 (POK1), and GAMMA TUBULIN COMPLEX PROTEIN 4 (GCP4).The findings that MPK6 localized to preprophase bands (PPBs) and phragmoplasts while the mpk6-4 mutant transformed with MPK6AEF (alanine (A)–glutamic acid (E)–phenylanine (F)) showed a root phenotype similar to that of yda1 demonstrated that MPK6 is an important player downstream of YODA. These data indicate that YODA and MPK6 are involved in post-embryonic root development through an auxin-dependent mechanism regulating cell division and mitotic microtubule (PPB and phragmoplast) organization. PMID:24923680

  2. Effects of Arg-Gly-Asp-modified elastin-like polypeptide on pseudoislet formation via up-regulation of cell adhesion molecules and extracellular matrix proteins.

    PubMed

    Lee, Kyeong-Min; Jung, Gwon-Soo; Park, Jin-Kyu; Choi, Seong-Kyoon; Jeon, Won Bae

    2013-03-01

    Extracellular matrix (ECM) plays an important role in controlling the β-cell morphology, survival and insulin secretary functions. An RGD-modified elastin-like polypeptide (RGD-ELP), TGPG[VGRGD(VGVPG)(6)](20)WPC, has been reported previously as a bioactive matrix. In this study, to investigate whether RGD-ELP affects β-cell growth characteristics and insulin secretion, β-TC6 cells were cultured on the RGD-ELP coatings prepared via thermally induced phase transition. On RGD-ELP, β-TC6 cells clustered into an islet-like architecture with high cell viability. Throughout 7days' culture, the proliferation rate of the cells within a pseudoislet was similar to that of monolayer culture. Under high glucose (25mM), β-TC6 pseudoislets showed up-regulated insulin gene expression and exhibited glucose-stimulated insulin secretion. Importantly, the mRNA and protein abundances of cell adhesion molecules (CAM) E-cadherin and connexin-36 were much higher in pseudoislets than in monolayer cells. The siRNA-mediated inhibition of E-cadherin or connexin-36 expression severely limited pseudoislet formation. In addition, the mRNA levels of collagen types I and IV, fibronectin and laminin were significantly elevated in pseudoislets. The results suggest that RGD-ELP promotes pseudoislet formation via up-regulation of the CAM and ECM components. The functional roles of RGD-ELP are discussed in respect of its molecular composition.

  3. PPARdelta promotes wound healing by up-regulating TGF-beta1-dependent or -independent expression of extracellular matrix proteins.

    PubMed

    Ham, Sun Ah; Kim, Hyo Jung; Kim, Hyun Joon; Kang, Eun Sil; Eun, So Young; Kim, Gil Hyeong; Park, Myung Hyun; Woo, Im Sun; Kim, Hye Jung; Chang, Ki Churl; Lee, Jae Heun; Seo, Han Geuk

    2010-06-01

    Although the peroxisome proliferator-activated receptor (PPAR) delta has been implicated in the wound healing process, its exact role and mechanism of action have not been fully elucidated. Our previous findings showed that PPARdelta induces the expression of the transforming growth factor (TGF)-beta1, which has been implicated in the deposit of extracellular matrix proteins. Here, we demonstrate that administration of GW501516, a specific PPARdelta ligand, significantly promoted wound closure in the experimental mouse and had a profound effect on the expression of collagen types I and III, alpha-smooth muscle actin, pSmad3 and TGF-beta1, which play a pivotal role in wound healing processes. Activation of PPARdelta increased migration of human epidermal keratinocytes and dermal fibroblasts in in vitro scrape-wounding assays. Addition of a specific ALK5 receptor inhibitor SB431542 significantly suppressed GW501516-induced migration of human keratinocytes and fibroblasts. In these cells, activated PPARdelta also induced the expression of collagen types I and III and fibronectin in a TGF-beta1-dependent or -independent manner. The effect of PPARdelta on the expression of type III collagen was dually regulated by the direct binding of PPARdelta and Smad3 to a direct repeat-1 site and a Smad-binding element, respectively, of the type III gene promoter. Taken together, these results demonstrated that PPARdelta plays an important role in skin wound healing in vivo and that it functions by accelerating extracellular matrix-mediated cellular interactions in a process mediated by the TGF-beta1/Smad3 signaling-dependent or - independent pathway.

  4. Proteins involved on TGF-β pathway are up-regulated during the acute phase of experimental Chagas disease.

    PubMed

    Ferreira, Roberto Rodrigues; de Souza, Elen Mello; de Oliveira, Fabiane Loiola; Ferrão, Patrícia Mello; Gomes, Leonardo Henrique Ferreira; Mendonça-Lima, Leila; Meuser-Batista, Marcelo; Bailly, Sabine; Feige, Jean Jacques; de Araujo-Jorge, Tania Cremonini; Waghabi, Mariana Caldas

    2016-05-01

    Studies developed by our group in the last years have shown the involvement of TGF-β in acute and chronic Chagas heart disease, with elevated plasma levels and activated TGF-β cell signaling pathway as remarkable features of patients in the advanced stages of this disease, when high levels of cardiac fibrosis is present. Imbalance in synthesis and degradation of extracellular matrix components is the basis of pathological fibrosis and TGF-β is considered as one of the key regulators of this process. In the present study, we investigated the activity of the TGF-β signaling pathway, including receptors and signaling proteins activation in the heart of animals experimentally infected with Trypanosoma cruzi during the period that mimics the acute phase of Chagas disease. We observed that T. cruzi-infected animals presented increased expression of TGF-β receptors. Overexpression of receptors was followed by an increased phosphorylation of Smad2/3, p38 and ERK. Furthermore, we correlated these activities with cellular factors involved in the fibrotic process induced by TGF-β. We observed that the expression of collagen I, fibronectin and CTGF were increased in the heart of infected animals on day 15 post-infection. Correlated with the increased TGF-β activity in the heart, we found that serum levels of total TGF-β were significantly higher during acute infection. Taken together, our data suggest that the commitment of the heart associates with increased activity of TGF-β pathway and expression of its main components. Our results, confirm the importance of this cytokine in the development and maintenance of cardiac damage caused by T. cruzi infection.

  5. Accumulated SET protein up-regulates and interacts with hnRNPK, increasing its binding to nucleic acids, the Bcl-xS repression, and cellular proliferation.

    PubMed

    Almeida, Luciana O; Garcia, Cristiana B; Matos-Silva, Flavia A; Curti, Carlos; Leopoldino, Andréia M

    2014-02-28

    SET and hnRNPK are proteins involved in gene expression and regulation of cellular signaling. We previously demonstrated that SET accumulates in head and neck squamous cell carcinoma (HNSCC); hnRNPK is a prognostic marker in cancer. Here, we postulate that SET and hnRNPK proteins interact to promote tumorigenesis. We performed studies in HEK293 and HNSCC (HN6, HN12, and HN13) cell lines with SET/hnRNPK overexpression and knockdown, respectively. We found that SET and/or hnRNPK protein accumulation increased cellular proliferation. SET accumulation up-regulated hnRNPK mRNA and total/phosphorylated protein, promoted hnRNPK nuclear location, and reduced Bcl-x mRNA levels. SET protein directly interacted with hnRNPK, increasing both its binding to nucleic acids and Bcl-xS repression. We propose that hnRNPK should be a new target of SET and that SET-hnRNPK interaction, in turn, has potential implications in cell survival and malignant transformation.

  6. Accumulated SET protein up-regulates and interacts with hnRNPK, increasing its binding to nucleic acids, the Bcl-xS repression, and cellular proliferation

    SciTech Connect

    Almeida, Luciana O.; Garcia, Cristiana B.; Matos-Silva, Flavia A.; Curti, Carlos; Leopoldino, Andréia M.

    2014-02-28

    Highlights: • hnRNPK is a new target of SET. • SET regulates hnRNPK. • SET and hnRNPK accumulation promotes tumorigenesis. • SET accumulation is a potential model to study genes regulated by SET-hnRNPK. - Abstract: SET and hnRNPK are proteins involved in gene expression and regulation of cellular signaling. We previously demonstrated that SET accumulates in head and neck squamous cell carcinoma (HNSCC); hnRNPK is a prognostic marker in cancer. Here, we postulate that SET and hnRNPK proteins interact to promote tumorigenesis. We performed studies in HEK293 and HNSCC (HN6, HN12, and HN13) cell lines with SET/hnRNPK overexpression and knockdown, respectively. We found that SET and/or hnRNPK protein accumulation increased cellular proliferation. SET accumulation up-regulated hnRNPK mRNA and total/phosphorylated protein, promoted hnRNPK nuclear location, and reduced Bcl-x mRNA levels. SET protein directly interacted with hnRNPK, increasing both its binding to nucleic acids and Bcl-xS repression. We propose that hnRNPK should be a new target of SET and that SET–hnRNPK interaction, in turn, has potential implications in cell survival and malignant transformation.

  7. Cadmium up-regulates transcription of the steroidogenic acute regulatory protein (StAR) gene through phosphorylated CREB rather than SF-1 in K28 cells.

    PubMed

    Park, Soo-Yun; Gomes, Cynthia; Oh, Sung-Dug; Soh, Jaemog

    2015-04-01

    Cadmium is a widely used heavy metal in industry and affects the male reproductive system of animals, including humans, as a result of occupational and environmental exposures. However, the molecular mechanism underlying its effect on steroidogenesis in gonads remains unclear. In this study, we demonstrated that exposure of K28 mouse testicular Leydig tumor cells to cadmium led to a significant increase in the mRNA level, promoter activity and protein level of the steroidogenic acute regulatory protein (StAR), an essential factor for steroid biosynthesis. It has been well documented that StAR gene transcription is regulated by multiple transcription factors, including cAMP-responsive element binding protein (CREB) family members and SF-1. Cadmium treatment caused an increase in CREB phosphorylation but did not alter the CREB protein level in the nucleus. EMSA studies revealed that cadmium-induced phosphorylated CREB formed specific complexes with the proximal region of the StAR gene promoter. Furthermore, co-transfection with a CREB expression plasmid significantly increased cadmium-induced StAR promoter activity. However, the nuclear level and the affinity of SF-1 protein for the StAR proximal promoter were dramatically decreased upon exposure to cadmium. Taken together, these results suggest that cadmium up-regulates StAR gene expression through phosphorylated CREB rather than through SF-1 in mouse testicular Leydig cells. PMID:25786521

  8. Knockout of the abundant Trichomonas vaginalis hydrogenosomal membrane protein TvHMP23 increases hydrogenosome size but induces no compensatory up-regulation of paralogous copies.

    PubMed

    Brás, Xavier Pereira; Zimorski, Verena; Bolte, Kathrin; Maier, Uwe-G; Martin, William F; Gould, Sven B

    2013-05-01

    The Trichomonas vaginalis genome encodes up to 60000 genes, many of which stem from genome duplication events. Paralogous copies thus accompany most T. vaginalis genes, a phenomenon that limits genetic manipulation. We characterized one of the parasite's most abundant hydrogenosomal membrane proteins, TvHMP23, which is phylogenetically distinct from canonical metabolite carriers, and which localizes to the inner hydrogenosomal membrane as shown through sub-organellar fractionation and protease protection assays. Knockout of Tvhmp23 through insertion of the selectable neomycin marker led to a size increase of hydrogenosomes, the first knockout-induced phenotypes reported for Trichomonas, but no growth impairment. The transcriptional response of its four paralogous copies then analyzed revealed that they are not up-regulated, and hence do not compensate for the Tvhmp23 knockout. PMID:23499435

  9. Fibroblast growth factor 2 inhibits up-regulation of bone morphogenic proteins and their receptors during osteoblastic differentiation of human mesenchymal stem cells

    SciTech Connect

    Biver, Emmanuel; Soubrier, Anne-Sophie; Thouverey, Cyril; Cortet, Bernard; Broux, Odile; Caverzasio, Joseph; Hardouin, Pierre

    2012-11-02

    Highlights: Black-Right-Pointing-Pointer FGF modulates BMPs pathway in HMSCs by down-regulating BMP/BMPR expression. Black-Right-Pointing-Pointer This effect is mediated by ERK and JNK MAPKs pathways. Black-Right-Pointing-Pointer Crosstalk between FGF and BMPs must be taken into account in skeletal bioengineering. Black-Right-Pointing-Pointer It must also be considered in the use of recombinant BMPs in orthopedic and spine surgeries. -- Abstract: Understanding the interactions between growth factors and bone morphogenic proteins (BMPs) signaling remains a crucial issue to optimize the use of human mesenchymal stem cells (HMSCs) and BMPs in therapeutic perspectives and bone tissue engineering. BMPs are potent inducers of osteoblastic differentiation. They exert their actions via BMP receptors (BMPR), including BMPR1A, BMPR1B and BMPR2. Fibroblast growth factor 2 (FGF2) is expressed by cells of the osteoblastic lineage, increases their proliferation and is secreted during the healing process of fractures or in surgery bone sites. We hypothesized that FGF2 might influence HMSC osteoblastic differentiation by modulating expressions of BMPs and their receptors. BMP2, BMP4, BMPR1A and mainly BMPR1B expressions were up-regulated during this differentiation. FGF2 inhibited HMSCs osteoblastic differentiation and the up-regulation of BMPs and BMPR. This effect was prevented by inhibiting the ERK or JNK mitogen-activated protein kinases which are known to be activated by FGF2. These data provide a mechanism explaining the inhibitory effect of FGF2 on osteoblastic differentiation of HMSCs. These crosstalks between growth and osteogenic factors should be considered in the use of recombinant BMPs in therapeutic purpose of fracture repair or skeletal bioengineering.

  10. Leptin increases HER2 protein levels through a STAT3-mediated up-regulation of Hsp90 in breast cancer cells.

    PubMed

    Giordano, Cinzia; Vizza, Donatella; Panza, Salvatore; Barone, Ines; Bonofiglio, Daniela; Lanzino, Marilena; Sisci, Diego; De Amicis, Francesca; Fuqua, Suzanne A W; Catalano, Stefania; Andò, Sebastiano

    2013-06-01

    Obesity condition confers risks to breast cancer development and progression, and several reports indicate that the adipokine leptin, whose synthesis and plasma levels increase with obesity, might play an important role in modulating breast cancer cell phenotype. Functional crosstalk occurring between leptin and different signaling molecules contribute to breast carcinogenesis. In this study, we show, in different human breast cancer cell lines, that leptin enhanced the expression of a chaperone protein Hsp90 resulting in increased HER2 protein levels. Silencing of Hsp90 gene expression by RNA interference abrogated leptin-mediated HER2 up-regulation. Leptin effects were dependent on JAK2/STAT3 activation, since inhibition of this signaling cascade by AG490 or ectopic expression of a STAT3 dominant negative abrogated leptin-induced HER2 and Hsp90 expressions. Functional experiments showed that leptin treatment significantly up-regulated human Hsp90 promoter activity. This occurred through an enhanced STAT3 transcription factor binding to its specific responsive element located in the Hsp90 promoter region as revealed by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Analysis of HER2, Akt and MAPK phosphorylation levels revealed that leptin treatment amplified the responsiveness of breast cancer cells to growth factor stimulation. Furthermore, we found that long-term leptin exposure reduced sensitivity of breast cancer cells to the antiestrogen tamoxifen. In the same experimental conditions, the combined treatment of tamoxifen with the Hsp90 inhibitor 17-AAG completely abrogated leptin-induced anchorage-independent breast cancer cell growth. In conclusion, our results highlight, for the first time, the ability of the adipocyte-secreted factor leptin to modulate Hsp90/HER2 expressions in breast cancer cells providing novel insights into the molecular mechanism linking obesity to breast cancer growth and progression.

  11. Global quantitative proteomics reveal up-regulation of endoplasmic reticulum stress response proteins upon depletion of eIF5A in HeLa cells

    PubMed Central

    Mandal, Ajeet; Mandal, Swati; Park, Myung Hee

    2016-01-01

    The eukaryotic translation factor, eIF5A, is a translation factor essential for protein synthesis, cell growth and animal development. By use of a adenoviral eIF5A shRNA, we have achieved an effective depletion of eIF5A in HeLa cells and undertook in vivo comprehensive proteomic analyses to examine the effects of eIF5A depletion on the total proteome and to identify cellular pathways influenced by eIF5A. The proteome of HeLa cells transduced with eIF5A shRNA was compared with that of scramble shRNA-transduced counterpart by the iTRAQ method. We identified 972 proteins consistently detected in three iTRAQ experiments and 104 proteins with significantly altered levels (protein ratio ≥1.5 or ≤0.66, p-value ≤0.05) at 72 h and/or 96 h of Ad-eIF5A-shRNA transduction. The altered expression levels of key pathway proteins were validated by western blotting. Integration of functional ontology with expression data of the 104 proteins revealed specific biological processes that are prominently up- or down-regulated. Heatmap analysis and Cytoscape visualization of biological networks identified protein folding as the major cellular process affected by depletion of eIF5A. Our unbiased, quantitative, proteomic data demonstrate that the depletion of eIF5A leads to endoplasmic reticulum stress, an unfolded protein response and up-regulation of chaperone expression in HeLa cells. PMID:27180817

  12. 17β-Estradiol attenuates saturated fatty acid diet-induced liver injury in ovariectomized mice by up-regulating hepatic senescence marker protein-30.

    PubMed

    Fukui, Michiaki; Senmaru, Takafumi; Hasegawa, Goji; Yamazaki, Masahiro; Asano, Mai; Kagami, Yayoi; Ishigami, Akihito; Maruyama, Naoki; Iwasa, Koichi; Kitawaki, Jo; Itoh, Yoshito; Okanoue, Takeshi; Ohta, Mitsuhiro; Obayashi, Hiroshi; Nakamura, Naoto

    2011-11-18

    Senescence marker protein-30 (SMP30) plays an important role in intracellular Ca(2+) homeostasis. The aim of the present study was to investigate the effects of estrogens on liver apoptotic damage and changes in SMP30 expression induced by a high saturated fatty acid diet (HSFD). Ovariectomized mice (OVX) and sham-operated mice (SHAM) were randomly divided into five groups: SHAM fed a normal diet (SHAM/ND), SHAM fed HSFD (SHAM/HSFD), OVX fed ND (OVX/ND), OVX fed HSFD (OVX/HSFD) and OVX fed HSFD with 17β-estradiol (E2) supplementation using an implanted slow-release pellet (OVX/HSFD+E2). After 8 weeks, markers of endoplasmic reticulum (ER) stress and apoptosis, and levels of tumor necrosis factor-α (TNFα and SMP30 expression were investigated. Compared with SHAM/ND, OVX/HSFD mice showed significantly increased spliced X-box protein-1 (s-XBP1), phosphorylated eukaryotic initiation factor-2α (p-eIF2α), glucose-regulated protein 78 (GPR78), C/EBP homologous protein (CHOP), cytosolic cytochrome c, caspase-3 activity, and TNFα, and significantly decreased SMP30. These differences in OVX/HSFD mice were restored to the levels of SHAM/ND mice by E2 supplementation. These results suggest that E2 supplementation attenuates HSFD-induced liver apoptotic death in ovariectomized mice by up-regulating SMP30. PMID:22037452

  13. Beneficial effect of spironolactone administration on ethynylestradiol-induced cholestasis in the rat: involvement of up-regulation of multidrug resistance-associated protein 2.

    PubMed

    Ruiz, María L; Villanueva, Silvina S M; Luquita, Marcelo G; Ikushiro, Shin-ichi; Mottino, Aldo D; Catania, Viviana A

    2007-11-01

    The effect of spironolactone (SL) administration on 17alpha-ethynylestradiol (EE)-induced cholestasis was studied, with emphasis on expression and activity of Mrps. Adult male Wistar rats were divided into the following groups: EE (5 mg/kg daily for 5 days, s.c.), SL (200 micromol/kg daily for 3 days, i.p.), EE+SL (same doses, SL administered the last 3 days of EE treatment), and controls. SL prevented the decrease in bile salt-independent fraction of bile flow induced by EE, in association with normalization of biliary excretion of glutathione. Western blot studies indicate that EE decreased the expression of multidrug resistance-associated protein 2 (Mrp2) by 41% and increased that of Mrp3 by 200%, whereas SL only affected Mrp2 expression (+60%) with respect to controls. The EE+SL group showed increased levels of Mrp2 and Mrp3 to the same extent as that registered for the individual treatments. Real-time polymerase chain reaction studies indicated that up-regulation of Mrp2 and Mrp3 by SL and EE, respectively, was at the transcriptional level. To estimate Mrp2 and Mrp3 activities, apical and basolateral excretion of acetaminophen glucuronide (APAP-glu), a common substrate for both transporters, was measured in the recirculating isolated perfused liver model. Biliary/perfusate excretion ratio was decreased in EE (-88%) and increased in SL (+36%) with respect to controls. Coadministration of rats with SL partially prevented (-53%) impairment induced by EE in this ratio. In conclusion, SL administration to EE-induced cholestatic rats counteracted the decrease in bile flow and biliary excretion of glutathione and APAP-glu, a model Mrp substrate, findings associated with up-regulation of Mrp2 expression. PMID:17686906

  14. The Aspergillus fumigatus StuA Protein Governs the Up-Regulation of a Discrete Transcriptional Program during the Acquisition of Developmental CompetenceD⃞

    PubMed Central

    Sheppard, Donald C.; Doedt, Thomas; Chiang, Lisa Y.; Kim, H. Stanley; Chen, Dan; Nierman, William C.; Filler, Scott G.

    2005-01-01

    Members of the Asm1p, Phd1p, Sok2p, Efg1p, and StuAp (APSES) family of fungal proteins regulate morphogenesis and virulence in ascomycetes. We cloned the Aspergillus fumigatus APSES gene encoding StuAp and demonstrated that stuA transcription is markedly up-regulated after the acquisition of developmental competence. A. fumigatus ΔstuA mutants were impaired in their ability to undergo asexual reproduction. Conidiophore morphology was markedly abnormal, and only small numbers of dysmorphic conidia were produced, which exhibited precocious germination. Whole genome transcriptional analysis during the onset of developmental competence was performed and identified a subset of developmentally regulated genes that were stuA dependent, including a cluster of putative secondary metabolite biosynthesis genes, genes encoding proteins implicated in the regulation of morphogenesis, and genes encoding allergens and other antigenic proteins. Additionally, hyphae of the ΔstuA mutant displayed reduced expression of the catalase gene CAT1 and were hypersusceptible to hydrogen peroxide. PMID:16207816

  15. Isolation and characterization of a novel rat factor H-related protein that is up-regulated in glomeruli under complement attack.

    PubMed

    Ren, Guohui; Doshi, Mona; Hack, Bradley K; Alexander, Jessy J; Quigg, Richard J

    2002-12-13

    The factor H family in humans is composed of seven distinct proteins, including factor H-related proteins (FHR) 1-5. All members contain tandemly arranged short consensus repeats (SCR) typical of the regulators of complement activation gene family. FHR-5 is unusual for this group of proteins, as it was initially identified as a component of immune deposits in glomerular diseases. During our cloning of the cDNA for rat factor H from glomerular epithelial cells (GEC), we identified an alternative 2729-bp cDNA transcript. The translated sequence encoded a protein containing 11 SCRs, most similar to SCRs 7-15 and 19-20 in native rat factor H, which is the same basic structure of human FHR-5. As such, this rat protein was termed FHR. Recombinant rat FHR produced in a eukaryotic expression system had a molecular mass of 78 kDa. In functional studies, recombinant FHR bound C3b and inhibited the complement alternative pathway in a dose-dependent fashion. Given the prominent expression of FHR-5 in human membranous nephropathy, a disease in which complement activation occurs in the vicinity of GEC, the expression of FHR in a rat model of this disease was evaluated. In both in vitro and in vivo models of complement activation on the GEC, FHR mRNA was up-regulated by a factor of 3-6-fold compared with controls in which complement could not be activated. Thus, we have identified a novel factor H family member in rats. This FHR protein is analogous to human FHR-5, both in structure and in potential involvement in glomerular immune complex diseases.

  16. Coordinated action of IgE and a B-cell-stimulatory factor on the CD23 receptor molecule up-regulates B-lymphocyte growth.

    PubMed Central

    Guy, G R; Gordon, J

    1987-01-01

    The CD23 (BLAST-2) antigen, recently identified as the low-affinity IgE receptor of B lymphocytes, has also been implicated as the focus for growth-promoting signals delivered to activated B cells by a low molecular weight B-cell growth factor (BCGF). Here we show that IgE and BCGF can coordinate B-lymphocyte growth through their opposing effects on the CD23 molecule. While the activation of purified quiescent B cells with phorbol 12-myristate 13-acetate led to the induction of 45-kDa CD23 at the surface membrane, the inclusion of IgE increased CD23 expression by a factor of approximately equal to 5. The addition of BCGF resulted in the rapid release of a 35-kDa form of CD23 from the cell surface. This shed molecule is associated with autocrine growth factor activity. Substantially more of this material was generated by BCGF acting on cells that had been stimulated in the presence of IgE. The combined effects of IgE and BCGF on DNA synthesis in activated B cells were more than additive. IgE similarly augmented the stimulatory capacity of a CD23 antibody that mimics the biological actions of BCGF. Binding of the anti-receptor antibody to its 45-kDa target at the B-cell surface also prompted the release of the 35-kDa soluble species. These results demonstrate a pleiotropy in the CD23 molecule with regard to both ligand binding and the subsequent behavior of the receptor. The ability of this single receptor to orchestrate a B-lymphocyte response through a variety of ligands and its role in normal and transformed autocrine growth are discussed. Images PMID:2957693

  17. Survivin enhances telomerase activity via up-regulation of specificity protein 1- and c-Myc-mediated human telomerase reverse transcriptase gene transcription

    SciTech Connect

    Endoh, Teruo; Tsuji, Naoki; Asanuma, Koichi; Yagihashi, Atsuhito; Watanabe, Naoki . E-mail: watanabn@sapmed.ac.jp

    2005-05-01

    Suppression of apoptosis is thought to contribute to carcinogenesis. Survivin, a member of the inhibitor-of-apoptosis family, blocks apoptotic signaling activated by various cellular stresses. Since elevated expression of survivin observed in human cancers of varied origin was associated with poor patient survival, survivin has attracted growing attention as a potential target for cancer treatment. Immortalization of cells also is required for carcinogenesis; telomere length maintenance by telomerase is required for cancer cells to proliferate indefinitely. Yet how cancer cells activate telomerase remains unclear. We therefore examined possible interrelationships between survivin expression and telomerase activity. Correlation between survivin and human telomerase reverse transcriptase (hTERT) expression was observed in colon cancer tissues, and overexpression of survivin enhanced telomerase activity by up-regulation of hTERT expression in LS180 human colon cancer cells. DNA-binding activities of specificity protein 1 (Sp1) and c-Myc to the hTERT core promoter were increased in survivin gene transfectant cells. Phosphorylation of Sp1 and c-Myc at serine and threonine residues was enhanced by survivin, while total amounts of these proteins were unchanged. Further, 'knockdown' of survivin by a small inhibitory RNA decreased Sp1 and c-Myc phosphorylation. Thus survivin participates not only in inhibition of apoptosis, but also in prolonging cellular lifespan.

  18. p21(Cip1) up-regulated during histone deacetylase inhibitor-induced CD4(+) T-cell anergy selectively associates with mitogen-activated protein kinases.

    PubMed

    Selma Dagtas, Ayse; Gilbert, Kathleen M

    2010-04-01

    Histone deacetylase inhibitor n-butyrate induced proliferative unresponsiveness in antigen-stimulated murine CD4(+) T cells. T cells anergized by n-butyrate demonstrated reduced interleukin-2 (IL-2) secretion and decreased activating protein 1 (AP-1) activity upon restimulation. Mechanistic studies determined that the cyclin-dependent kinase (cdk) inhibitor p21(Cip1) was up-regulated in the anergic CD4(+) T cells. p21(Cip1) is known to inhibit the cell cycle through its interaction with cdk, proliferating cell nuclear antigen (PCNA) or c-Jun N-terminal kinase (JNK). p21(Cip1) did not preferentially associate with PCNA or cdk in anergic T helper type 1 (Th1) cells. Instead, among the three interaction partners, p21(Cip1) was found to interact with phospho-JNK and phospho-c-jun selectively in the anergic CD4(+) T cells. The activity of c-jun and downstream transcription factor AP-1 were suppressed in the anergic Th1 cells. In contrast, p21(Cip1) and the two phospho-proteins were never detected concurrently in the control CD4(+) T cells. The n-butyrate-induced p21(Cip1)-mediated inhibition of JNK and c-jun represents a novel potential mechanism by which proliferative unresponsiveness was maintained in CD4(+) T cells.

  19. Convergence of multiple signaling pathways is required to coordinately up-regulate mtDNA and mitochondrial biogenesis during T cell activation.

    PubMed

    D'Souza, Anthony D; Parikh, Neal; Kaech, Susan M; Shadel, Gerald S

    2007-12-01

    The quantity and activity of mitochondria vary dramatically in tissues and are modulated in response to changing cellular energy demands and environmental factors. The amount of mitochondrial DNA (mtDNA), which encodes essential subunits of the oxidative phosphorylation complexes required for cellular ATP production, is also tightly regulated, but by largely unknown mechanisms. Using murine T cells as a model system, we have addressed how specific signaling pathways influence mitochondrial biogenesis and mtDNA copy number. T cell receptor (TCR) activation results in a large increase in mitochondrial mass and membrane potential and a corresponding amplification of mtDNA, consistent with a vital role for mitochondrial function for growth and proliferation of these cells. Independent activation of protein kinase C (via PMA) or calcium-related pathways (via ionomycin) had differential and sub-maximal effects on these mitochondrial parameters, as did activation of naïve T cells with proliferative cytokines. Thus, the robust mitochondrial biogenesis response observed upon TCR activation requires synergy of multiple downstream signaling pathways. One such pathway involves AMP-activated protein kinase (AMPK), which we show has an unprecedented role in negatively regulating mitochondrial biogenesis that is mammalian target of rapamycin (mTOR)-dependent. That is, inhibition of AMPK after TCR signaling commences results in excessive, but uncoordinated mitochondrial proliferation. Thus mitochondrial biogenesis is not under control of a single master regulatory circuit, but rather requires the convergence of multiple signaling pathways with distinct downstream consequences on the organelle's structure, composition, and function.

  20. Convergence of multiple signaling pathways is required to coordinately up-regulate mtDNA and mitochondrial biogenesis during T cell activation

    PubMed Central

    D’Souza, Anthony D.; Parikh, Neal; Kaech, Susan M.; Shadel, Gerald S.

    2009-01-01

    The quantity and activity of mitochondria vary dramatically in tissues and are modulated in response to changing cellular energy demands and environmental factors. The amount of mitochondrial DNA (mtDNA), which encodes essential subunits of the oxidative phosphorylation complexes required for cellular ATP production, is also tightly regulated, but by largely unknown mechanisms. Using murine T cells as a model system, we have addressed how specific signaling pathways influence mitochondrial biogenesis and mtDNA levels. T cell receptor (TCR) activation results in a large increase in mitochondrial mass and membrane potential and a corresponding increase of mtDNA copy number, indicating the vital role for mitochondrial function for the growth and proliferation of these cells. Independent activation of protein kinase C (via PMA) or calcium-related pathways (via ionomycin) had differential and sub-maximal effects on these mitochondrial parameters, as did activation of naïve T cells with proliferative cytokines. Thus, the robust mitochondrial biogenesis response observed upon TCR activation requires synergy of multiple downstream signaling pathways. One such pathway involves AMP-activated protein kinase (AMPK), which we show has an unprecedented role in negatively regulating mitochondrial biogenesis that is mammalian target of rapamycin (mTOR)-dependent. That is, inhibition of AMPK after TCR signaling commences results in excessive, but uncoordinated mitochondrial proliferation. We propose that mitochondrial biogenesis is not under control of a master regulatory circuit, but rather requires the convergence of multiple signaling pathways with distinct downstream consequences on the organelle’s structure, composition, and function. PMID:17890163

  1. Hepatitis B virus X protein mutant HBxΔ127 promotes proliferation of hepatoma cells through up-regulating miR-215 targeting PTPRT

    SciTech Connect

    Liu, Fabao; You, Xiaona; Chi, Xiumei; Wang, Tao; Ye, Lihong; Niu, Junqi; Zhang, Xiaodong

    2014-02-07

    Highlights: • Relative to wild type HBx, HBX mutant HBxΔ127 strongly enhances cell proliferation. • Relative to wild type HBx, HBxΔ127 remarkably up-regulates miR-215 in hepatoma cells. • HBxΔ127-elevated miR-215 promotes cell proliferation via targeting PTPRT mRNA. - Abstract: The mutant of virus is a frequent event. Hepatitis B virus X protein (HBx) plays a vital role in the development of hepatocellular carcinoma (HCC). Therefore, the identification of potent mutant of HBx in hepatocarcinogenesis is significant. Previously, we identified a natural mutant of the HBx gene (termed HBxΔ127). Relative to wild type HBx, HBxΔ127 strongly enhanced cell proliferation and migration in HCC. In this study, we aim to explore the mechanism of HBxΔ127 in promotion of proliferation of hepatoma cells. Our data showed that both wild type HBx and HBxΔ127 could increase the expression of miR-215 in hepatoma HepG2 and H7402 cells. However, HBxΔ127 was able to significantly increase miR-215 expression relative to wild type HBx in the cells. We identified that protein tyrosine phosphatase, receptor type T (PTPRT) was one of the target genes of miR-215 through targeting 3′UTR of PTPRT mRNA. In function, miR-215 was able to promote the proliferation of hepatoma cells. Meanwhile anti-miR-215 could partially abolish the enhancement of cell proliferation mediated by HBxΔ127 in vitro. Knockdown of PTPRT by siRNA could distinctly suppress the decrease of cell proliferation mediated by anti-miR-215 in HepG2-XΔ127/H7402-XΔ127 cells. Moreover, we found that anti-miR-215 remarkably inhibited the tumor growth of hepatoma cells in nude mice. Collectively, relative to wild type HBx, HBxΔ127 strongly enhances proliferation of hepatoma cells through up-regulating miR-215 targeting PTPRT. Our finding provides new insights into the mechanism of HBx mutant HBxΔ127 in promotion of proliferation of hepatoma cells.

  2. TNF-α Up-Regulates Protein Level and Cell Surface Expression of the Leptin Receptor by Stimulating Its Export via a PKC-Dependent Mechanism

    PubMed Central

    Gan, Lixia; Guo, Kaiying; Cremona, Maria Laura; McGraw, Timothy E.; Leibel, Rudolph L.

    2012-01-01

    Increasing evidence suggests that inflammation/cytokines may modulate hypothalamic responses to leptin, which is a key regulator of energy homeostasis and inflammatory/stress responses. We investigated a possible role of TNF-α, a key early mediator of inflammation, in regulating the expression and trafficking of the long-isoform leptin receptor (LEPRb), the primary mediator of leptin signaling, in cultured cells. We found that TNF-α in a wide range of concentrations up-regulated LEPRb protein level and soluble LEPR (sLEPR) release via ectodomain shedding of LEPRb in multiple cell types, including neuronal cells. TNF-α also acutely increased LEPRb cell surface expression and leptin-induced STAT3 phosphorylation. In contrast, TNF-α had no significant effects on the protein level or cell surface expression of several other transmembrane proteins, including the transferrin receptor and cadherin. The stimulatory effects of TNF-α on LEPRb cell surface expression and sLEPR release were not dependent on de novo protein synthesis or functional lysosomes but were blocked by brefeldin A, suggesting that an intact Golgi or continuous endoplasmic reticulum to Golgi transport of newly synthesized proteins is required for these effects. However, TNF-α did not increase the half-life of cell surface LEPRb. Protein kinase C (PKC) inhibitor GF109203X abrogated the effects of TNF-α, whereas the pan-PKC activator phorbol 12-myristate 13-acetate mimicked the TNF-α effects. Taken together, our results suggest that TNF-α, via activation of PKC, regulates anterograde trafficking and/or degradation of LEPRb in the biosynthetic pathway, leading to concomitant increases in LEPRb protein level, cell surface expression, and sLEPR production. The finding that LEPRb cell surface expression and sLEPR production, key modulators of leptin sensitivity and bioavailability, are direct targets of TNF-α signaling could have a potentially important implication in the regulation of leptin

  3. The neuroprotective action of the mood stabilizing drugs lithium chloride and sodium valproate is mediated through the up-regulation of the homeodomain protein Six1.

    PubMed

    Plant, Kathryn E; Anderson, Elizabeth; Simecek, Nicole; Brown, Richard; Forster, Sam; Spinks, Jenny; Toms, Nick; Gibson, G Gordon; Lyon, Jon; Plant, Nick

    2009-02-15

    The mood stabilizing agents lithium chloride (LiCl) and sodium valproate (VPA) have recently gained interest as potential neuroprotective therapeutics. However, exploitation of these therapeutic applications is hindered by both a lack of molecular understanding of the mode of action, and a number of sub-optimal properties, including a relatively small therapeutic window and variable patient response. Human neuroblastoma cells (SH-SY5Y) were exposed to 1 mM lithium chloride or 1 mM sodium valproate for 6 h or 72 h, and transcriptomes measured by Affymetrix U133A/B microarray. Statistically significant gene expression changes were identified using SAM software, with selected changes confirmed at transcript (TaqMan) and protein (Western blotting) levels. Finally, anti-apoptotic action was measured by an in vitro fluorescent assay. Exposure of SH-SY5Y cells to therapeutically relevant concentrations of either lithium chloride or sodium valproate elicited 936 statistically significant changes in gene expression. Amongst these changes we observed a large (maximal 31.3-fold) increase in the expression of the homeodomain protein Six1, and have characterized the time- and dose-dependent up-regulation of this gene in response to both drugs. In addition, we demonstrate that, like LiCl or VPA treatment, Six1 over-expression protects SH-SY5Y cells from staurosporine-induced apoptosis via the blockade of caspsase-3 activation, whereas removal of Six1 protein via siRNA antagonises the ability of LiCl and VPA to protect SH-SY5Y cells from STS-induced apoptosis. These results provide a novel mechanistic rationale underlying the neuroprotective mechanism of LiCl and VPA, suggesting exciting possibilities for the development of novel therapeutic agents against neurodegenerative diseases such as Alzheimer's or Parkinsonism.

  4. The neuroprotective action of the mood stabilizing drugs lithium chloride and sodium valproate is mediated through the up-regulation of the homeodomain protein Six1

    SciTech Connect

    Plant, Kathryn E.; Anderson, Elizabeth; Simecek, Nicole; Brown, Richard; Forster, Sam; Spinks, Jenny; Toms, Nick; Gibson, G. Gordon; Lyon, Jon; Plant, Nick

    2009-02-15

    The mood stabilizing agents lithium chloride (LiCl) and sodium valproate (VPA) have recently gained interest as potential neuroprotective therapeutics. However, exploitation of these therapeutic applications is hindered by both a lack of molecular understanding of the mode of action, and a number of sub-optimal properties, including a relatively small therapeutic window and variable patient response. Human neuroblastoma cells (SH-SY5Y) were exposed to 1 mM lithium chloride or 1 mM sodium valproate for 6 h or 72 h, and transcriptomes measured by Affymetrix U133A/B microarray. Statistically significant gene expression changes were identified using SAM software, with selected changes confirmed at transcript (TaqMan) and protein (Western blotting) levels. Finally, anti-apoptotic action was measured by an in vitro fluorescent assay. Exposure of SH-SY5Y cells to therapeutically relevant concentrations of either lithium chloride or sodium valproate elicited 936 statistically significant changes in gene expression. Amongst these changes we observed a large (maximal 31.3-fold) increase in the expression of the homeodomain protein Six1, and have characterized the time- and dose-dependent up-regulation of this gene in response to both drugs. In addition, we demonstrate that, like LiCl or VPA treatment, Six1 over-expression protects SH-SY5Y cells from staurosporine-induced apoptosis via the blockade of caspsase-3 activation, whereas removal of Six1 protein via siRNA antagonises the ability of LiCl and VPA to protect SH-SY5Y cells from STS-induced apoptosis. These results provide a novel mechanistic rationale underlying the neuroprotective mechanism of LiCl and VPA, suggesting exciting possibilities for the development of novel therapeutic agents against neurodegenerative diseases such as Alzheimer's or Parkinsonism.

  5. HIV-1-Tat Protein Inhibits SC35-mediated Tau Exon 10 Inclusion through Up-regulation of DYRK1A Kinase.

    PubMed

    Kadri, Ferdous; Pacifici, Marco; Wilk, Anna; Parker-Struckhoff, Amanda; Del Valle, Luis; Hauser, Kurt F; Knapp, Pamela E; Parsons, Christopher; Jeansonne, Duane; Lassak, Adam; Peruzzi, Francesca

    2015-12-25

    The HIV-1 transactivator protein Tat is implicated in the neuronal damage that contributes to neurocognitive impairment affecting people living with HIV/AIDS. Aberrant splicing of TAU exon 10 results in tauopathies characterized by alterations in the proportion of TAU isoforms containing three (3R) or four (4R) microtubule-binding repeats. The splicing factor SC35/SRSF2 binds to nuclear RNA and facilitates the incorporation of exon 10 in the TAU molecule. Here, we utilized clinical samples, an animal model, and neuronal cell cultures and found that Tat promotes TAU 3R up-regulation through increased levels of phosphorylated SC35, which is retained in nuclear speckles. This mechanism involved Tat-mediated increased expression of DYRK1A and was prevented by DYRK1A silencing. In addition, we found that Tat associates with TAU RNA, further demonstrating that Tat interferes with host RNA metabolism in the absence of viral infection. Altogether, our data unravel a novel mechanism of Tat-mediated neuronal toxicity through dysregulation of the SC35-dependent alternative splicing of TAU exon 10. Furthermore, the increased immunostaining of DYRK1A in HIV+ brains without pathology points at dysregulation of DYRK1A as an early event in the neuronal complications of HIV infection. PMID:26534959

  6. Molecular cloning and characterization of a novel RING zinc-finger protein gene up-regulated under in vitro salt stress in cassava.

    PubMed

    dos Reis, Sávio Pinho; Tavares, Liliane de Souza Conceição; Costa, Carinne de Nazaré Monteiro; Brígida, Aílton Borges Santa; de Souza, Cláudia Regina Batista

    2012-06-01

    Cassava (Manihot esculenta Crantz) is one of the world's most important food crops. It is cultivated mainly in developing countries of tropics, since its root is a major source of calories for low-income people due to its high productivity and resistance to many abiotic and biotic factors. A previous study has identified a partial cDNA sequence coding for a putative RING zinc finger in cassava storage root. The RING zinc finger protein is a specialized type of zinc finger protein found in many organisms. Here, we isolated the full-length cDNA sequence coding for M. esculenta RZF (MeRZF) protein by a combination of 5' and 3' RACE assays. BLAST analysis showed that its deduced amino acid sequence has a high level of similarity to plant proteins of RZF family. MeRZF protein contains a signature sequence motif for a RING zinc finger at its C-terminal region. In addition, this protein showed a histidine residue at the fifth coordination site, likely belonging to the RING-H2 subgroup, as confirmed by our phylogenetic analysis. There is also a transmembrane domain in its N-terminal region. Finally, semi-quantitative RT-PCR assays showed that MeRZF expression is increased in detached leaves treated with sodium chloride. Here, we report the first evidence of a RING zinc finger gene of cassava showing potential role in response to salt stress.

  7. Fluoxetine up-regulates expression of cellular FLICE-inhibitory protein and inhibits LPS-induced apoptosis in hippocampus-derived neural stem cell

    SciTech Connect

    Chiou, S.-H. . E-mail: shchiou@vghtpe.gov.tw; Chen, S.-J. . E-mail: sjchen@vghtpe.gov.tw; Peng, C-H.; Chang, Y.-L.; Ku, H.-H.; Hsu, W.-M.; Ho, Larry L.-T.; Lee, C.-H.

    2006-05-05

    Fluoxetine is a widely used antidepressant compound which inhibits the reuptake of serotonin in the central nervous system. Recent studies have shown that fluoxetine can promote neurogenesis and improve the survival rate of neurons. However, whether fluoxetine modulates the proliferation or neuroprotection effects of neural stem cells (NSCs) needs to be elucidated. In this study, we demonstrated that 20 {mu}M fluoxetine can increase the cell proliferation of NSCs derived from the hippocampus of adult rats by MTT test. The up-regulated expression of Bcl-2, Bcl-xL and the cellular FLICE-inhibitory protein (c-FLIP) in fluoxetine-treated NSCs was detected by real-time RT-PCR. Our results further showed that fluoxetine protects the lipopolysaccharide-induced apoptosis in NSCs, in part, by activating the expression of c-FLIP. Moreover, c-FLIP induction by fluoxetine requires the activation of the c-FLIP promoter region spanning nucleotides -414 to -133, including CREB and SP1 sites. This effect appeared to involve the phosphatidylinositol-3-kinase-dependent pathway. Furthermore, fluoxetine treatment significantly inhibited the induction of proinflammatory factor IL-1{beta}, IL-6, and TNF-{alpha} in the culture medium of LPS-treated NSCs (p < 0.01). The results of high performance liquid chromatography coupled to electrochemical detection further confirmed that fluoxentine increased the functional production of serotonin in NSCs. Together, these data demonstrate the specific activation of c-FLIP by fluoxetine and indicate the novel role of fluoxetine for neuroprotection in the treatment of depression.

  8. The Mutant KRAS Gene Up-regulates BCL-XL Protein via STAT3 to Confer Apoptosis Resistance That Is Reversed by BIM Protein Induction and BCL-XL Antagonism.

    PubMed

    Zaanan, Aziz; Okamoto, Koichi; Kawakami, Hisato; Khazaie, Khashayarsha; Huang, Shengbing; Sinicrope, Frank A

    2015-09-25

    In colorectal cancers with oncogenic GTPase Kras (KRAS) mutations, inhibition of downstream MEK/ERK signaling has shown limited efficacy, in part because of failure to induce a robust apoptotic response. We studied the mechanism of apoptosis resistance in mutant KRAS cells and sought to enhance the efficacy of a KRAS-specific MEK/ERK inhibitor, GDC-0623. GDC-0623 was shown to potently up-regulate BIM expression to a greater extent versus other MEK inhibitors in isogenic KRAS HCT116 and mutant KRAS SW620 colon cancer cells. ERK silencing enhanced BIM up-regulation by GDC-0623 that was due to its loss of phosphorylation at Ser(69), confirmed by a BIM-EL phosphorylation-defective mutant (S69G) that increased protein stability and blocked BIM induction. Despite BIM and BIK induction, the isogenic KRAS mutant versus wild-type cells remained resistant to GDC-0623-induced apoptosis, in part because of up-regulation of BCL-XL. KRAS knockdown by a doxycycline-inducible shRNA attenuated BCL-XL expression. BCL-XL knockdown sensitized KRAS mutant cells to GDC-0623-mediated apoptosis, as did the BH3 mimetic ABT-263. GDC-0623 plus ABT-263 induced a synergistic apoptosis by a mechanism that includes release of BIM from its sequestration by BCL-XL. Furthermore, mutant KRAS activated p-STAT3 (Tyr(705)) in the absence of IL-6 secretion, and STAT3 knockdown reduced BCL-XL mRNA and protein expression. These data suggest that BCL-XL up-regulation by STAT3 contributes to mutant KRAS-mediated apoptosis resistance. Such resistance can be overcome by potent BIM induction and concurrent BCL-XL antagonism to enable a synergistic apoptotic response.

  9. Up-regulation of lipolysis genes and increased production of AMP-activated protein kinase protein in the skeletal muscle of rats after resistance training.

    PubMed

    An, Jae-Heung; Yoon, Jin-Hwan; Suk, Min-Hwa; Shin, Yun-A

    2016-06-01

    The purpose of this study was to investigate the expression of lipogenesis- and lipolysis-related genes and proteins in skeletal muscles after 12 weeks of resistance training. Sprague-Dawley rats (n=12) were randomly divided into control (resting) and resistance training groups. A tower-climbing exercise, in which rats climbed to the top of their cage with a weight applied to their tails, used for resistance training. After 12 weeks, rats from the resistance training group had lower body weights (411.66±14.71 g vs. 478.33±24.63 g in the control), there was no significant difference between the two groups in the concentrations of total cholesterol, and high or low density lipoprotein cholesterol. However, the concentration of triglyceride was lower in resistance-trained rats (59.83±14.05 μg/mL vs 93.33±33.89 μg/mL in the control). The mRNA expression levels of the lipogenesis-related genes sterol regulatory element binding protein-1c, acetyl-CoA carboxylase, and fatty acid synthase were not significantly different between the resistance-trained and control rats; however, mRNA expression of the lipolysis-related carnitine palmitoyl transferase 1 and malonyl-CoA decarboxylase increased significantly with resistance training. AMP-activated protein kinase protein levels also significantly increased in resistance training group compared with in the control group. These results suggested that resistance exercise training contributing to reduced weight gain may be in part be due to increase the lipolysis metabolism and energy expenditure in response to resistance training. PMID:27419110

  10. Up-regulation of lipolysis genes and increased production of AMP-activated protein kinase protein in the skeletal muscle of rats after resistance training

    PubMed Central

    An, Jae-Heung; Yoon, Jin-Hwan; Suk, Min-Hwa; Shin, Yun-A

    2016-01-01

    The purpose of this study was to investigate the expression of lipogenesis- and lipolysis-related genes and proteins in skeletal muscles after 12 weeks of resistance training. Sprague-Dawley rats (n=12) were randomly divided into control (resting) and resistance training groups. A tower-climbing exercise, in which rats climbed to the top of their cage with a weight applied to their tails, used for resistance training. After 12 weeks, rats from the resistance training group had lower body weights (411.66±14.71 g vs. 478.33±24.63 g in the control), there was no significant difference between the two groups in the concentrations of total cholesterol, and high or low density lipoprotein cholesterol. However, the concentration of triglyceride was lower in resistance-trained rats (59.83±14.05 μg/mL vs 93.33±33.89 μg/mL in the control). The mRNA expression levels of the lipogenesis-related genes sterol regulatory element binding protein-1c, acetyl-CoA carboxylase, and fatty acid synthase were not significantly different between the resistance-trained and control rats; however, mRNA expression of the lipolysis-related carnitine palmitoyl transferase 1 and malonyl-CoA decarboxylase increased significantly with resistance training. AMP-activated protein kinase protein levels also significantly increased in resistance training group compared with in the control group. These results suggested that resistance exercise training contributing to reduced weight gain may be in part be due to increase the lipolysis metabolism and energy expenditure in response to resistance training. PMID:27419110

  11. Up-Regulation of mRNA Ventricular PRNP Prion Protein Gene Expression in Air Pollution Highly Exposed Young Urbanites: Endoplasmic Reticulum Stress, Glucose Regulated Protein 78, and Nanosized Particles

    PubMed Central

    Villarreal-Calderon, Rodolfo; Franco-Lira, Maricela; González-Maciel, Angélica; Reynoso-Robles, Rafael; Harritt, Lou; Pérez-Guillé, Beatriz; Ferreira-Azevedo, Lara; Drecktrah, Dan; Zhu, Hongtu; Sun, Qiang; Torres-Jardón, Ricardo; Aragón-Flores, Mariana; Calderón-Garcidueñas, Ana; Diaz, Philippe; Calderón-Garcidueñas, Lilian

    2013-01-01

    Mexico City Metropolitan Area children and young adults exposed to high concentrations of air pollutants including fine and ultrafine particulate matter (PM) vs. clean air controls, exhibit myocardial inflammation and inflammasome activation with a differential right and left ventricular expression of key inflammatory genes and inflammasomes. We investigated the mRNA expression levels of the prion protein gene PRNP, which plays an important role in the protection against oxidative stress and metal toxicity, and the glucose regulated protein 78, a key protein in endoplasmic reticulum (ER) stress signaling, in ventricular autopsy samples from 30 children and young adults age 19.97 ± 6.8 years with a lifetime of low (n:4) vs. high (n:26) air pollution exposures. Light microscopy and transmission electron microscopy studies were carried out in human ventricles, and electron microscopy studies were also done in 5 young, highly exposed Mexico City dogs. There was significant left ventricular PRNP and bi-ventricular GRP78 mRNA up-regulation in Mexico City young urbanites vs. controls. PRNP up-regulation in the left ventricle was significantly different from the right, p < 0.0001, and there was a strong left ventricular PRNP and GRP78 correlation (p = 0.0005). Marked abnormalities in capillary endothelial cells, numerous nanosized particles in myocardial ER and in abnormal mitochondria characterized the highly exposed ventricles. Early and sustained cardiac ER stress could result in detrimental irreversible consequences in urban children, and while highly complex systems maintain myocardial homeostasis, failure to compensate for chronic myocardial inflammation, oxidative and ER stress, and particles damaging myocardial organelles may prime the development of pathophysiological cardiovascular states in young urbanites. Nanosized PM could play a key cardiac myocyte toxicity role. PMID:24287918

  12. Up-regulation of mRNA ventricular PRNP prion protein gene expression in air pollution highly exposed young urbanites: endoplasmic reticulum stress, glucose regulated protein 78, and nanosized particles.

    PubMed

    Villarreal-Calderon, Rodolfo; Franco-Lira, Maricela; González-Maciel, Angélica; Reynoso-Robles, Rafael; Harritt, Lou; Pérez-Guillé, Beatriz; Ferreira-Azevedo, Lara; Drecktrah, Dan; Zhu, Hongtu; Sun, Qiang; Torres-Jardón, Ricardo; Aragón-Flores, Mariana; Calderón-Garcidueñas, Ana; Diaz, Philippe; Calderón-Garcidueñas, Lilian

    2013-01-01

    Mexico City Metropolitan Area children and young adults exposed to high concentrations of air pollutants including fine and ultrafine particulate matter (PM) vs. clean air controls, exhibit myocardial inflammation and inflammasome activation with a differential right and left ventricular expression of key inflammatory genes and inflammasomes. We investigated the mRNA expression levels of the prion protein gene PRNP, which plays an important role in the protection against oxidative stress and metal toxicity, and the glucose regulated protein 78, a key protein in endoplasmic reticulum (ER) stress signaling, in ventricular autopsy samples from 30 children and young adults age 19.97 ± 6.8 years with a lifetime of low (n:4) vs. high (n:26) air pollution exposures. Light microscopy and transmission electron microscopy studies were carried out in human ventricles, and electron microscopy studies were also done in 5 young, highly exposed Mexico City dogs. There was significant left ventricular PRNP and bi-ventricular GRP78 mRNA up-regulation in Mexico City young urbanites vs. controls. PRNP up-regulation in the left ventricle was significantly different from the right, p < 0.0001, and there was a strong left ventricular PRNP and GRP78 correlation (p = 0.0005). Marked abnormalities in capillary endothelial cells, numerous nanosized particles in myocardial ER and in abnormal mitochondria characterized the highly exposed ventricles. Early and sustained cardiac ER stress could result in detrimental irreversible consequences in urban children, and while highly complex systems maintain myocardial homeostasis, failure to compensate for chronic myocardial inflammation, oxidative and ER stress, and particles damaging myocardial organelles may prime the development of pathophysiological cardiovascular states in young urbanites. Nanosized PM could play a key cardiac myocyte toxicity role. PMID:24287918

  13. Up-regulation of mRNA ventricular PRNP prion protein gene expression in air pollution highly exposed young urbanites: endoplasmic reticulum stress, glucose regulated protein 78, and nanosized particles.

    PubMed

    Villarreal-Calderon, Rodolfo; Franco-Lira, Maricela; González-Maciel, Angélica; Reynoso-Robles, Rafael; Harritt, Lou; Pérez-Guillé, Beatriz; Ferreira-Azevedo, Lara; Drecktrah, Dan; Zhu, Hongtu; Sun, Qiang; Torres-Jardón, Ricardo; Aragón-Flores, Mariana; Calderón-Garcidueñas, Ana; Diaz, Philippe; Calderón-Garcidueñas, Lilian

    2013-11-28

    Mexico City Metropolitan Area children and young adults exposed to high concentrations of air pollutants including fine and ultrafine particulate matter (PM) vs. clean air controls, exhibit myocardial inflammation and inflammasome activation with a differential right and left ventricular expression of key inflammatory genes and inflammasomes. We investigated the mRNA expression levels of the prion protein gene PRNP, which plays an important role in the protection against oxidative stress and metal toxicity, and the glucose regulated protein 78, a key protein in endoplasmic reticulum (ER) stress signaling, in ventricular autopsy samples from 30 children and young adults age 19.97 ± 6.8 years with a lifetime of low (n:4) vs. high (n:26) air pollution exposures. Light microscopy and transmission electron microscopy studies were carried out in human ventricles, and electron microscopy studies were also done in 5 young, highly exposed Mexico City dogs. There was significant left ventricular PRNP and bi-ventricular GRP78 mRNA up-regulation in Mexico City young urbanites vs. controls. PRNP up-regulation in the left ventricle was significantly different from the right, p < 0.0001, and there was a strong left ventricular PRNP and GRP78 correlation (p = 0.0005). Marked abnormalities in capillary endothelial cells, numerous nanosized particles in myocardial ER and in abnormal mitochondria characterized the highly exposed ventricles. Early and sustained cardiac ER stress could result in detrimental irreversible consequences in urban children, and while highly complex systems maintain myocardial homeostasis, failure to compensate for chronic myocardial inflammation, oxidative and ER stress, and particles damaging myocardial organelles may prime the development of pathophysiological cardiovascular states in young urbanites. Nanosized PM could play a key cardiac myocyte toxicity role.

  14. Expanding coordination chemistry from protein to protein assembly.

    PubMed

    Sanghamitra, Nusrat J M; Ueno, Takafumi

    2013-05-14

    Bioinorganic chemistry is of growing importance in the fields of nanomaterial science and biotechnology. Coordination of metals by biological systems is a crucial step in intricate enzymatic reactions such as photosynthesis, nitrogen fixation and biomineralization. Although such systems employ protein assemblies as molecular scaffolds, the important roles of protein assemblies in coordination chemistry have not been systematically investigated and characterized. Many researchers are joining the field of bioinorganic chemistry to investigate the inorganic chemistry of protein assemblies. This area is emerging as an important next-generation research field in bioinorganic chemistry. This article reviews recent progress in rational design of protein assemblies in coordination chemistry for integration of catalytic reactions using metal complexes, preparation of mineral biomimetics, and mechanistic investigations of biomineralization processes with protein assemblies. The unique chemical properties of protein assemblies in the form of cages, tubes, and crystals are described in this review.

  15. Inhibitory heterotrimeric GTP-binding proteins inhibit hydrogen peroxide-induced apoptosis by up-regulation of Bcl-2 via NF-{kappa}B in H1299 human lung cancer cells

    SciTech Connect

    Seo, Mi Ran; Nam, Hyo-Jung; Kim, So-Young; Juhnn, Yong-Sung

    2009-04-03

    Inhibitory heterotrimeric GTP-binding proteins (Gi proteins) mediate a variety of signaling pathways by coupling receptors and effectors to regulate cellular proliferation, differentiation, and apoptosis. However, the role of Gi proteins in the modulation of hydrogen peroxide-induced apoptosis is not clearly understood. Thus, we investigated the effect of Gi proteins on hydrogen peroxide-induced apoptosis and the underlying mechanisms in H1299 human lung cancer cells. The stable expression of constitutively active alpha subunits of Gi1 (G{alpha}i1QL), Gi2, or Gi3 inhibited hydrogen peroxide-induced apoptosis. The expression of G{alpha}i1QL up-regulated Bcl-2 expression, and the knockdown of Bcl-2 with siRNA abolished the anti-apoptotic effect of G{alpha}i1QL. G{alpha}i1 induced the transcription of Bcl-2 by activation of NF-{kappa}B, which resulted from an increase in NF-{kappa}B p50 protein. We conclude that G{alpha}i1 inhibits hydrogen peroxide-induced apoptosis of H1299 lung cancer cells by up-regulating the transcription of Bcl-2 through a p50-mediated NF-{kappa}B activation.

  16. Role of protein kinase D2 phosphorylation on Tyr in modulation by ghrelin of Helicobacter pylori-induced up-regulation in gastric mucosal matrix metalloproteinase-9 (MMP-9) secretion.

    PubMed

    Slomiany, B L; Slomiany, A

    2016-06-01

    Matrix metalloproteinas-9 (MMP-9) is a glycosylated endopeptidase associated with host reaction to microbial endotoxins and also characterizes gastric mucosal inflammatory response to H. pylori infection. Here, we report on the factors involved in gastric mucosal MMP-9 secretion in response to H. pylori LPS, and the effect of hormone, ghrelin. We show that both the LPS-elicited induction in MMP-9 secretion and also the modulatory influence of ghrelin occur at the level of MMP-9 processing between the endoplasmic reticulum (ER) and Golgi. Further, we demonstrate that the LPS effect is associated with up-regulation in the activation of Arf1, a small GTPase of the ADP-ribosylation factor family, and the recruitment and phosphorylation of protein kinase D2 (PKD2), involved in the secretory cargo processing in the Golgi. Moreover, we reveal that the LPS-induced up-regulation in MMP-9 secretion is reflected in a marked increase in PKCδ-mediated PKD2 phosphorylation on Ser, while the modulatory effect of ghrelin is manifested by the SFK-PTKs-dependent phosphorylation of PKD2 on Tyr. Thus, our findings demonstrate the role of Arf1/PKD2 in mediation of H. pylori LPS-induced up-regulation in gastric mucosal MMP-9 secretion and suggest the modulatory mechanism of ghrelin action. PMID:27209313

  17. Decreased secretion and unfolded protein response up-regulation are correlated with intracellular retention for single-chain antibody variants produced in yeast

    PubMed Central

    Xu, Ping; Robinson, Anne Skaja

    2009-01-01

    Heterologous protein expression can easily overwhelm a cell's capacity to properly fold protein, initiating the unfolded protein response (UPR), and resulting in a loss of protein expression. In the current model of the unfolded protein response, the chaperone BiP modulates the activation of the UPR due to its interactions with the signaling protein Ire1p and newly synthesized proteins. In this research, 4−4−20 scFv variants were generated by rational design to alter BiP binding to newly synthesized scFv proteins or via directed evolution aimed at improved secretion. Interestingly, the predicted BiP binding ability did not correlate significantly with the unfolded protein response. However, pulse-chase analysis of scFv fate revealed that mutants with a decreased ER residence time were more highly secreted, indicating that improved protein folding was more likely the cause for improved secretion. In fact, decreased secretion correlated with increased binding by BiP, as determined by co-immune precipitation studies. This suggests that the algorithm is not useful for in vivo prediction of variants, and that in vivo screens are more effective for finding variants with improved properties. PMID:19415776

  18. Hepatitis B virus X protein up-regulates C4b-binding protein α through activating transcription factor Sp1 in protection of hepatoma cells from complement attack

    PubMed Central

    Feng, Guoxing; Li, Jiong; Zheng, Minying; Yang, Zhe; Liu, Yunxia; Zhang, Shuqin; Ye, Lihong; Zhang, Weiying; Zhang, Xiaodong

    2016-01-01

    Hepatitis B virus X protein (HBx) plays crucial roles in the development of hepatocellular carcinoma (HCC). We previously showed that HBx protected hepatoma cells from complement attack by activation of CD59. Moreover, in this study we found that HBx protected hepatoma cells from complement attack by activation of C4b-binding protein α (C4BPα), a potent inhibitor of complement system. We observed that HBx were positively correlated with those of C4BPα in clinical HCC tissues. Mechanistically, HBx activated the promoter core region of C4BPα, located at −1199/−803nt, through binding to transcription factor Sp1. In addition, chromatin immunoprecipitation (ChIP) assays showed that HBx was able to bind to the promoter of C4BPα, which could be blocked by Sp1 silencing. Functionally, knockdown of C4BPα obviously increased the deposition of C5b-9, a complex of complement membrane attack, and remarkably abolished the HBx-induced resistance of hepatoma cells from complement attack in vitro and in vivo. Thus, we conclude that HBx up-regulates C4BPα through activating transcription factor Sp1 in protection of liver cancer cells from complement attack. Our finding provides new insights into the mechanism by which HBx enhances protection of hepatoma cells from complement attack. PMID:27050367

  19. Lambda-cyhalothrin disrupts the up-regulation effect of 17β-estradiol on post-synaptic density 95 protein expression via estrogen receptor α-dependent Akt pathway.

    PubMed

    Wang, Qunan; Xia, Xin; Deng, Xiaomei; Li, Nian; Wu, Daji; Zhang, Long; Yang, Chengwei; Tao, Fangbiao; Zhou, Jiangning

    2016-03-01

    Lambda-cyhalothrin (LCT), one of the type II pyrethroids, has been widely used throughout the world. The estrogenic effect of LCT to increase cell proliferation has been well established. However, whether the estrogenic effect of LCT will influence neurodevelopment has not been investigated. In addition, 17β-Estradiol (E2) plays a crucial role in neurodevelopment and induces an increase in synaptic proteins. The post-synaptic density 95 (PSD95) protein, which is involved in the development of the structure and function of new spines and localized with estrogen receptor α (ERα) at the post-synaptic density (PSD), was detected in our study by using hippocampal neuron cell line HT22. We found that LCT up-regulated PSD95 and ERα expression, estrogen receptor (ER) antagonist ICI182,780 and phosphatidylinositol-4; 5-bisphosphate 3-kinase (PI3K) inhibitor LY294,002 blocked this effect. In addition, LCT disrupted the promotion effect of E2 on PSD95. To investigate whether the observed changes are caused by ERα-dependent signaling activation, we next detected the effects of LCT on the ERα-mediated PI3K-Protein kinase B (PKB/Akt)-eukaryotic initiation factor (eIF) 4E-binding protein 1 (4E-BP1) pathway. There existed an activation of Akt and the downstream factor 4E-BP1 after LCT treatment. In addition, LCT could disrupt the activation effect of E2 on the Akt pathway. However, no changes in cAMP response element-binding protein (CREB) activation and PSD95 messenger ribonucleic acid (mRNA) were observed. Our findings demonstrated that LCT could increase the PSD95 protein level via the ERα-dependent Akt pathway, and LCT might disrupt the up-regulation effect of E2 on PSD95 protein expression via this signaling pathway. PMID:26969072

  20. Sodium butyrate up-regulates cathelicidin gene expression via activator protein-1 and histone acetylation at the promoter region in a human lung epithelial cell line, EBC-1.

    PubMed

    Kida, Yutaka; Shimizu, Takashi; Kuwano, Koichi

    2006-05-01

    The antimicrobial protein cathelicidin is considered to play an important role in the defense mechanisms against bacterial infection. Recent studies show that sodium butyrate induces cathelicidin gene expression in human colonic, gastric and hepatic cells. However, little is known about the precise regulatory mechanisms underlying sodium butyrate-induced cathelicidin gene expression. In this study, we examined the regulatory mechanisms involved in sodium butyrate-induced cathelicidin gene expression using a human lung epithelial cell line, EBC-1. Our results indicate that sodium butyrate induces both cathelicidin mRNA and protein expression. Moreover, deletion or mutation of a putative activator protein-1 (AP-1) binding site in the cathelicidin gene promoter abrogated the response to sodium butyrate stimulation. Three different mitogen-activated protein (MAP) kinase inhibitors suppressed sodium butyrate-induced transactivation of the cathelicidin promoter. Electrophoretic mobility shift assays (EMSA) showed that nuclear extracts prepared from sodium butyrate-stimulated EBC-1 cells generated specific binding to probe including a putative AP-1 binding site in the cathelicidin gene promoter. Furthermore, chromatin immunoprecipitation (ChIP) assays demonstrated that sodium butyrate augmented histone acetylation of the cathelicidin promoter in EBC-1 cells. Therefore, these results indicate that AP-1 and histone acetylation of the cathelicidin promoter play a critical role in the regulation of inducible cathelicidin gene expression in EBC-1 cells stimulated with sodium butyrate.

  1. Sucrose prevents up-regulation of senescence-associated genes in carnation petals.

    PubMed

    Hoeberichts, Frank A; van Doorn, Wouter G; Vorst, Oscar; Hall, Robert D; van Wordragen, Monique F

    2007-01-01

    cDNA microarrays were used to characterize senescence-associated gene expression in petals of cut carnation (Dianthus caryophyllus) flowers, sampled from anthesis to the first senescence symptoms. The population of PCR fragments spotted on these microarrays was enriched for flower-specific and senescence-specific genes, using subtractive hybridization. About 90% of the transcripts showed a large increase in quantity, approximately 25% transiently, and about 65% throughout the 7 d experiment. Treatment with silver thiosulphate (STS), which blocks the ethylene receptor and prevented the normal senescence symptoms, prevented the up-regulation of almost all of these genes. Sucrose treatment also considerably delayed visible senescence. Its effect on gene expression was very similar to that of STS, suggesting that soluble sugars act as a repressor of ethylene signal transduction. Two fragments that encoded a carnation EIN3-like (EIL) protein were isolated, some of which are key transcription factors that control ethylene response genes. One of these (Dc-EIL3) was up-regulated during senescence. Its up-regulation was delayed by STS and prevented by sucrose. Sucrose, therefore, seems to repress ethylene signalling, in part, by preventing up-regulation of Dc-EIL3. Some other transcription factors displayed an early increase in transcript abundance: a MYB-like DNA binding protein, a MYC protein, a MADS-box factor, and a zinc finger protein. Genes suggesting a role in senescence of hormones other than ethylene encoded an Aux/IAA protein, which regulate transcription of auxin-induced genes, and a cytokinin oxidase/dehydrogenase, which degrades cytokinin. Taken together, the results suggest a master switch during senescence, controlling the co-ordinated up-regulation of numerous ethylene response genes. Dc-EIL3 might be (part of) this master switch.

  2. High Doses of Ursodeoxycholic Acid Up-Regulate the Expression of Placental Breast Cancer Resistance Protein in Patients Affected by Intrahepatic Cholestasis of Pregnancy

    PubMed Central

    Azzaroli, Francesco; Raspanti, Maria Elena; Simoni, Patrizia; Montagnani, Marco; Lisotti, Andrea; Cecinato, Paolo; Arena, Rosario; Simonazzi, Giuliana; Farina, Antonio; Rizzo, Nicola; Mazzella, Giuseppe

    2013-01-01

    Background Ursodeoxycholic acid (UDCA) administration in intrahepatic cholestasis of pregnancy (ICP) induces bile acids (BA) efflux from the foetal compartment, but the molecular basis of this transplacental transport is only partially defined. Aim To determine if placental breast cancer resistance protein (BCRP), able to transport BA, is regulated by UDCA in ICP. Methods 32 pregnant women with ICP (14 untreated, 34.9±5.17 years; 18 treated with UDCA - 25 mg/Kg/day, 32.7±4.62 years,) and 12 healthy controls (33.4±3.32 years) agreed to participate in the study. Placentas were obtained at delivery and processed for membrane extraction. BCRP protein expression was evaluated by immunoblotting techniques and chemiluminescence quantified with a luminograph measuring emitted photons; mRNA expression with real time PCR. Statistical differences between groups were evaluated by ANOVA with Dunn’s Multiple Comparison test. Results BCRP was expressed only on the apical membrane of the syncytiotrophoblast. A significant difference was observed among the three groups both for mRNA (ANOVA, p = 0.0074) and protein (ANOVA, p<0.0001) expression. BCRP expression was similar in controls and in the untreated ICP group. UDCA induced a significant increase in placental BCRP mRNA and protein expression compared to controls (350.7±106.3 vs 100±18.68% of controls, p<0.05 and 397.8±56.02 vs 100±11.44% of controls, p<0.001, respectively) and untreated ICP (90.29±17.59% of controls, p<0.05 and 155.0±13.87%, p<0.01). Conclusion Our results confirm that BCRP is expressed only on the apical membrane of the syncytiotrophoblast and show that ICP treatment with high dose UDCA significantly upregulates placental BCRP expression favouring BA efflux from the foetal compartment. PMID:23717540

  3. Coordinated Evolution of Influenza A Surface Proteins

    PubMed Central

    Plotkin, Joshua B.; Bazykin, Georgii A.

    2015-01-01

    The surface proteins hemagglutinin (HA) and neuraminidase (NA) of human influenza A virus evolve under selection pressures to escape adaptive immune responses and antiviral drug treatments. In addition to these external selection pressures, some mutations in HA are known to affect the adaptive landscape of NA, and vice versa, because these two proteins are physiologically interlinked. However, the extent to which evolution of one protein affects the evolution of the other one is unknown. Here we develop a novel phylogenetic method for detecting the signatures of such genetic interactions between mutations in different genes – that is, inter-gene epistasis. Using this method, we show that influenza surface proteins evolve in a coordinated way, with mutations in HA affecting subsequent spread of mutations in NA and vice versa, at many sites. Of particular interest is our finding that the oseltamivir-resistance mutations in NA in subtype H1N1 were likely facilitated by prior mutations in HA. Our results illustrate that the adaptive landscape of a viral protein is remarkably sensitive to its genomic context and, more generally, that the evolution of any single protein must be understood within the context of the entire evolving genome. PMID:26247472

  4. Up-regulation and interaction of the plasma membrane H(+)-ATPase and the 14-3-3 protein are involved in the regulation of citrate exudation from the broad bean (Vicia faba L.) under Al stress.

    PubMed

    Chen, Qi; Guo, Chuan-Long; Wang, Ping; Chen, Xuan-Qin; Wu, Kong-Huan; Li, Kui-Zhi; Yu, Yong-Xiong; Chen, Li-Mei

    2013-09-01

    Our previous study showed that citrate excretion coupled with a concomitant release of protons was involved in aluminum (Al) resistance in the broad bean. Furthermore, genes encoding plasma membrane (PM) H(+)-ATPase (vha2) and the 14-3-3 protein (vf14-3-3b) were up-regulated by Al in Al-resistant (YD) broad bean roots. In this study, the roles of PM H(+)-ATPase (E.C. 3.6.3.6) and the 14-3-3 protein in the regulation of citrate secretion were further investigated in Al-resistant (YD) and Al-sensitive (AD) broad bean cultivars under Al stress. The results showed that greater citrate exudation was positively correlated with higher activities of PM H(+)-ATPase in roots of YD than AD. Real-time RT-PCR analysis revealed that vha2 was clearly up-regulated by Al in YD but not in AD roots, whereas the transcription levels of vf14-3-3b were elevated in a time-dependent manner in both YD and AD roots. Immunoprecipitation and Western analysis suggested that phosphorylation and interaction with the vf14-3-3b protein of the VHA2 were enhanced in YD roots but not in AD roots with increasing Al treatment time. Fusicoccin or adenosine 5'-monophosphate increased or decreased the interaction between the phosphorylated VHA2 and the vf14-3-3b protein, followed by an enhancement or reduction of the PM H(+)-ATPase activity and citrate exudation in both cultivars under Al stress conditions, respectively. Taken together, these results suggested that Al enhanced the expression and interaction of the PM H(+)-ATPase and the 14-3-3 protein, which thereby led to higher activity of the PM H(+)-ATPase and more citrate exudation from YD plants.

  5. Curcumin suppresses constitutive activation of STAT-3 by up-regulating protein inhibitor of activated STAT-3 (PIAS-3) in ovarian and endometrial cancer cells.

    PubMed

    Saydmohammed, Manush; Joseph, Doina; Syed, Viqar

    2010-05-15

    Signal transducer and activator of transcription-3 (STAT-3) is constitutively activated in ovarian and endometrial cancers and is implicated in uncontrolled cell growth. Thus, its disruption could be an effective approach to control tumorigenesis. Curcumin is a dihydroxyphenolic compound, with proven anti-cancer efficacy in various cancer models. We examined the anti-tumor mechanism of curcumin on STAT-3 and on the negative regulators of STAT-3, including suppressors of cytokine signaling proteins (SOCS-1 and SOCS-3), protein inhibitors of activated STAT (PIAS-1 and PIAS-3), and SH2 domain-containing phosphatases (SHP-1 and SHP-2) in ovarian and endometrial cancer cell lines. Treatment of cancer cells with curcumin induced a dose- and time-dependent decrease of constitutive IL-6 expression and of constitutive and IL-6-induced STAT-3 phosphorylation, which is associated with decreased cell viability and increased cleavage of caspase-3. The inhibition of STAT-3 activation by curcumin was reversible, and phosphorylated STAT-3 levels returned to control levels 24 h after curcumin removal. Compared to normal cells baseline expression of SOCS-3 was high in cancer cells and a marked decrease in SOCS-3 expression was seen following curcumin treatment. Overexpression of SOCS-3 in curcumin-treated cells increased expression of phosphorylated STAT-3 and resulted in increased cell viability. Normal ovarian and endometrial cells exhibited high expression of PIAS-3 protein, whereas in cancer cells the expression was greatly reduced. Curcumin increased PIAS-3 expression in cancer cells. Of significance, siRNA-mediated knockdown of PIAS-3 overcomes the inhibitory effect of curcumin on STAT-3 phosphorylation and cell viability. In conclusion, curcumin suppresses JAK-STAT signaling via activation of PIAS-3, thus attenuating STAT-3 phosphorylation and tumor cell growth.

  6. Metformin-induced mitochondrial function and ABCD2 up-regulation in X-linked adrenoleukodystrophy involves AMP-activated protein kinase.

    PubMed

    Singh, Jaspreet; Olle, Brittany; Suhail, Hamid; Felicella, Michelle M; Giri, Shailendra

    2016-07-01

    X-linked adrenoleukodystrophy (X-ALD) is a progressive neurometabolic disease caused by mutations/deletions in the Abcd1 gene. Similar mutations/deletions in the Abcd1 gene often result in diagonally opposing phenotypes of mild adrenomyeloneuropathy and severe neuroinflammatory cerebral adrenoleukodystrophy (ALD), which suggests involvement of downstream modifier genes. We recently documented the first evidence of loss of AMP-activated protein kinase α1 (AMPKα1) in ALD patient-derived cells. Here, we report the novel loss of AMPKα1 in postmortem brain white matter of patients with ALD phenotype. Pharmacological activation of AMPK can rescue the mitochondrial dysfunction and inhibit the pro-inflammatory response. The FDA approved anti-diabetic drug Metformin, a well-known AMPK activator, induces mitochondrial biogenesis and is documented for its anti-inflammatory role. We observed a dose-dependent activation of AMPKα1 in metformin-treated X-ALD patient-derived fibroblasts. Metformin also induced mitochondrial oxidative phosphorylation and ATP levels in X-ALD patient-derived fibroblasts. Metformin treatment decreased very long chain fatty acid levels and pro-inflammatory cytokine gene expressions in X-ALD patient-derived cells. Abcd2 [adrenoleukodystrophy protein-related protein] levels were increased in metformin-treated X-ALD patient-derived fibroblasts and Abcd1-KO mice primary mixed glial cells. Abcd2 induction was AMPKα1-dependent since metformin failed to induce Abcd2 levels in AMPKα1-KO mice-derived primary mixed glial cells. In vivo metformin (100 mg/Kg) in drinking water for 60 days induced Abcd2 levels and mitochondrial oxidative phosphorylation protein levels in the brain and spinal cord of Abcd1-KO mice. Taken together, these results provide proof-of-principle for therapeutic potential of metformin as a useful strategy for correcting the metabolic and inflammatory derangements in X-ALD by targeting AMPK. There is no effective therapy for inherited

  7. Metformin-induced mitochondrial function and ABCD2 up-regulation in X-linked adrenoleukodystrophy involves AMP-activated protein kinase.

    PubMed

    Singh, Jaspreet; Olle, Brittany; Suhail, Hamid; Felicella, Michelle M; Giri, Shailendra

    2016-07-01

    X-linked adrenoleukodystrophy (X-ALD) is a progressive neurometabolic disease caused by mutations/deletions in the Abcd1 gene. Similar mutations/deletions in the Abcd1 gene often result in diagonally opposing phenotypes of mild adrenomyeloneuropathy and severe neuroinflammatory cerebral adrenoleukodystrophy (ALD), which suggests involvement of downstream modifier genes. We recently documented the first evidence of loss of AMP-activated protein kinase α1 (AMPKα1) in ALD patient-derived cells. Here, we report the novel loss of AMPKα1 in postmortem brain white matter of patients with ALD phenotype. Pharmacological activation of AMPK can rescue the mitochondrial dysfunction and inhibit the pro-inflammatory response. The FDA approved anti-diabetic drug Metformin, a well-known AMPK activator, induces mitochondrial biogenesis and is documented for its anti-inflammatory role. We observed a dose-dependent activation of AMPKα1 in metformin-treated X-ALD patient-derived fibroblasts. Metformin also induced mitochondrial oxidative phosphorylation and ATP levels in X-ALD patient-derived fibroblasts. Metformin treatment decreased very long chain fatty acid levels and pro-inflammatory cytokine gene expressions in X-ALD patient-derived cells. Abcd2 [adrenoleukodystrophy protein-related protein] levels were increased in metformin-treated X-ALD patient-derived fibroblasts and Abcd1-KO mice primary mixed glial cells. Abcd2 induction was AMPKα1-dependent since metformin failed to induce Abcd2 levels in AMPKα1-KO mice-derived primary mixed glial cells. In vivo metformin (100 mg/Kg) in drinking water for 60 days induced Abcd2 levels and mitochondrial oxidative phosphorylation protein levels in the brain and spinal cord of Abcd1-KO mice. Taken together, these results provide proof-of-principle for therapeutic potential of metformin as a useful strategy for correcting the metabolic and inflammatory derangements in X-ALD by targeting AMPK. There is no effective therapy for inherited

  8. Osteopontin, a chemotactic protein with cytokine-like properties, is up-regulated in muscle injury caused by Bothrops lanceolatus (fer-de-lance) snake venom.

    PubMed

    Barbosa-Souza, Valéria; Contin, Daniel Kiss; Filho, Waldemar Bonventi; de Araújo, Albetiza Lôbo; Irazusta, Silvia Pierre; da Cruz-Höfling, Maria Alice

    2011-10-01

    Osteopontin (OPN) is a chemotactic, adhesive protein whose receptors include some integrins and matrix proteins known to have role in inflammatory and repair processes. We examined the time course of OPN expression at acute and chronic stages after intramuscular injection of Bothrops lanceolatus venom in rats. Additionally, we examined the expression of CD68 (a marker for phagocytic macrophages) and the myogenic factors, myoD and myogenin. There was a biphasic upregulation of OPN (6-48 h and 3-14 days post-venom), i.e., during acute inflammation and myogenic cell proliferation and differentiation phases. OPN was detected in CD68 + macrophages, fibroblasts, normal and damaged myofibers, myoblasts and myotubes. Myogenin was expressed in the cytoplasm (atypical pattern) and nucleus of myoblasts and myotubes from 18 h to 7 days, after which it was expressed only in nuclei. Macrophage numbers, OPN and myogenin expression were still elevated at 7, 14 and 7 days. At 3 days, when OPN achieved the peak, some clusters of myoblasts were within regions of intense collagen deposition. Fibrosis may represent limitation for repairing processes and may explain the small diameter of regenerated fibers at 21 days post-venom. The expression of OPN in the course of venom-induced damage and regeneration suggests stages-specific mediation role along the whole process. PMID:21839764

  9. Chronic psychosocial stress in male mice causes an up-regulation of scavenger receptor class B type 1 protein in the adrenal glands.

    PubMed

    Füchsl, Andrea M; Uschold-Schmidt, Nicole; Reber, Stefan O

    2013-07-01

    Mice exposed to chronic subordinate colony housing (CSC, 19 days) show an exaggerated adrenal corticosterone response to an acute heterotypic stressor (elevated platform (EPF), 5 min) despite no difference from EPF-exposed single-housed control (SHC) mice in corticotropin (ACTH) secretion. In the present study, we asked the question whether this CSC-induced increase in adrenal capability to produce and secrete corticosterone is paralleled by an enhanced adrenal availability and/or mobilization capacity of the corticosterone precursor molecule cholesterol. Employing oil-red staining and western blot analysis we revealed comparable relative density of cortical lipid droplets and relative protein expression of hormone-sensitive lipase, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and low-density lipoprotein receptor (LDL-R) between CSC and SHC mice. However, relative protein expression of the scavenger receptor class B type 1 (SR-BI) was increased following CSC exposure. Moreover, analysis of plasma high-density lipoprotein-cholesterol (HDL-C) and LDL-cholesterol (LDL-C) revealed increased LDL-C levels in CSC mice. Together with the pronounced increase in adrenal weight, evidently mediated by hyperplasia of adrenocortical cells, these data strongly indicate an enhanced adrenal availability of and capacity to mobilize cholesterol in chronic psychosocially-stressed mice, contributing to their increased in vivo corticosterone response during acute heterotypic stressor exposure.

  10. Up-regulation of Translation Eukaryotic Initiation Factor 4E in Nucleophosmin 1 Haploinsufficient Cells Results in Changes in CCAAT Enhancer-binding Protein α Activity

    PubMed Central

    Khanna-Gupta, Arati; Abayasekara, Nirmalee; Levine, Michelle; Sun, Hong; Virgilio, Maria; Nia, Navid; Halene, Stephanie; Sportoletti, Paolo; Jeong, Jee-Yeong; Pandolfi, Pier Paolo; Berliner, Nancy

    2012-01-01

    NPM1 is a ubiquitously expressed nucleolar phosphoprotein, the gene for which maps to chromosome 5q35 in close proximity to a commonly deleted region associated with (del)5q, a type of myelodysplastic syndrome (MDS). This region is also a frequent target of deletions in de novo and therapy-related MDS/acute myeloid leukemia. Previous studies have shown that Npm1+/− mice develop an MDS-like disease that transforms to acute myeloid leukemia over time. To better understand the mechanism by which NPM1 haploinsufficiency causes an MDS phenotype, we generated factor-dependent myeloid cell lines from the bone marrow of Npm1+/+ and Npm1+/− mice and demonstrated compromised neutrophil-specific gene expression in the MNPM1+/− cells. We attribute these observations to increased levels of the shorter, dominant negative leukemogenic isoform (p30) of CCAAT enhancer-binding protein α (C/EBPα). We show that this increase is caused, in part, by elevated levels of the activated translation initiation factor eIF4E, overexpression of which also increases translation of C/EBPαp30 in HEK293 cells. In a positive feedback loop, eIF4E expression is further elevated both at the mRNA and protein levels by C/EBPαp30 but not by the full-length C/EBPαp42. Re-expression of C/EBPαp42 or NPM1 but not C/EBPαp30 in MNPM1+/− cells partially rescues the myeloid phenotype. Our observations suggest that the aberrant feed-forward pathway that keeps eIF4E and C/EBPαp30 elevated in NPM1+/− cells contributes to the MDS phenotype associated with NPM1 deficiency. PMID:22851180

  11. Transcriptional up-regulation of inhibitory PAS domain protein gene expression by hypoxia-inducible factor 1 (HIF-1): a negative feedback regulatory circuit in HIF-1-mediated signaling in hypoxic cells.

    PubMed

    Makino, Yuichi; Uenishi, Rie; Okamoto, Kensaku; Isoe, Tsubasa; Hosono, Osamu; Tanaka, Hirotoshi; Kanopka, Arvydas; Poellinger, Lorenz; Haneda, Masakazu; Morimoto, Chikao

    2007-05-11

    The inhibitory PAS (Per/Arnt/Sim) domain protein (IPAS), a dominant negative regulator of hypoxia-inducible transcription factors (HIFs), is potentially implicated in negative regulation of angiogenesis in such tissues as the avascular cornea of the eye. We have previously shown IPAS mRNA expression is up-regulated in hypoxic tissues, which at least in part involves hypoxia-dependent alternative splicing of the transcripts from the IPAS/HIF-3alpha locus. In the present study, we demonstrate that a hypoxia-driven transcriptional mechanism also plays a role in augmentation of IPAS gene expression. Isolation and analyses of the promoter region flanking to the first exon of IPAS gene revealed a functional hypoxia response element at position -834 to -799, whereas the sequence upstream of the HIF-3alpha first exon scarcely responded to hypoxic stimuli. A transient transfection experiment demonstrated that HIF-1alpha mediates IPAS promoter activation via the functional hypoxia response element under hypoxic conditions and that a constitutively active form of HIF-1alpha is sufficient for induction of the promoter in normoxic cells. Moreover, chromatin immunoprecipitation and electrophoretic mobility shift assays showed binding of the HIF-1 complex to the element in a hypoxia-dependent manner. Taken together, HIF-1 directly up-regulates IPAS gene expression through a mechanism distinct from RNA splicing, providing a further level of negative feedback gene regulation in adaptive responses to hypoxic/ischemic conditions. PMID:17355974

  12. Up-regulation of serotonin receptor 2B mRNA and protein in the peri-infarcted area of aged rats and stroke patients

    PubMed Central

    Bădescu, George Mihai; Bogdan, Catalin; Weston, Ria; Slevin, Mark; Di Napoli, Mario; Popa-Wagner, Aurel

    2016-01-01

    Despite the fact that a high proportion of elderly stroke patients develop mood disorders, the mechanisms underlying late-onset neuropsychiatric and neurocognitive symptoms have so far received little attention in the field of neurobiology. In rodents, aged animals display depressive symptoms following stroke, whereas young animals recover fairly well. This finding has prompted us to investigate the expression of serotonin receptors 2A and 2B, which are directly linked to depression, in the brains of aged and young rats following stroke. Although the development of the infarct was more rapid in aged rats in the first 3 days after stroke, by day 14 the cortical infarcts were similar in size in both age groups i.e. 45% of total cortical volume in young rats and 55.7% in aged rats. We also found that the expression of serotonin receptor type B mRNA was markedly increased in the perilesional area of aged rats as compared to the younger counterparts. Furthermore, histologically, HTR2B protein expression in degenerating neurons was closely associated with activated microglia both in aged rats and human subjects. Treatment with fluoxetine attenuated the expression of Htr2B mRNA, stimulated post-stroke neurogenesis in the subventricular zone and was associated with an improved anhedonic behavior and an increased activity in the forced swim test in aged animals. We hypothesize that HTR2B expression in the infarcted territory may render degenerating neurons susceptible to attack by activated microglia and thus aggravate the consequences of stroke. PMID:27013593

  13. Magnesium modification up-regulates the bioactivity of bone morphogenetic protein-2 upon calcium phosphate cement via enhanced BMP receptor recognition and Smad signaling pathway.

    PubMed

    Ding, Sai; Zhang, Jing; Tian, Yu; Huang, Baolin; Yuan, Yuan; Liu, Changsheng

    2016-09-01

    Efficient presentation of growth factors is one of the great challenges in tissue engineering. In living systems, bioactive factors exist in soluble as well as in matrix-bound forms, both of which play an integral role in regulating cell behaviors. Herein, effect of magnesium on osteogenic bioactivity of recombinant human bone morphogenetic protein-2 (rhBMP-2) was investigated systematically with a series of Mg modified calcium phosphate cements (xMCPCs, x means the content of magnesium phosphate cement wt%) as matrix model. The results indicated that the MCPC, especially 5MCPC, could promote the rhBMP-2-induced in vitro osteogenic differentiation via Smad signaling of C2C12 cells. Further studies demonstrated that all MCPC substrates exhibited similar rhBMP-2 release rate and preserved comparable conformation and biological activity of the released rhBMP-2. Also, the ionic extracts of MCPC made little difference to the bioactivity of rhBMP-2, either in soluble or in matrix-bound forms. However, with the quartz crystal microbalance (QCM), we observed a noticeable enhancement of rhBMP-2 mass-uptake on 5MCPC as well as a better recognition of the bound rhBMP-2 to BMPR IA and BMPR II. In vivo results demonstrated a better bone regeneration capacity of 5MCPC/rhBMP-2. From the above, our results demonstrated that it was the Mg anchored on the underlying substrates that tailored the way of rhBMP-2 bound on MCPC, and thus facilitated the recognition of BMPRs to stimulate osteogenic differentiation. The study will guide the development of Mg-doped bioactive bone implants for tissue regeneration. PMID:27156155

  14. A novel antitumor activity of deguelin targeting the insulin-like growth factor (IGF) receptor pathway via up-regulation of IGF-binding protein-3 expression in breast cancer

    PubMed Central

    Suh, Young-Ah; Kim, Jai-Hyun; Sung, Myung A; Boo, Hye-Jin; Yun, Hye Jeong; Lee, Sun-Hye; Lee, Hyo-Jong; Suh, Young-Ger; Kim, Kyu-Won; Lee, Ho-Young

    2013-01-01

    In this study, we investigated the antitumor effects of deguelin in several human breast cancer cells in vitro and in vivo. Deguelin inhibited cell viability and the anchorage-dependent and anchorage-independent colony formation of triple-negative (MDA-MB-231 and MDA-MB-468) and triple-positive (MCF-7) breast cancer cells, and it significantly reduced the growth of MCF-7 cell xenograft tumors. The induction of apoptosis, inhibition of insulin-like growth factor-1 receptor (IGF-1R) signaling activation, and up-regulation of IGF-binding protein-3 (IGFBP-3) expression may be associated with deguelin-mediated antitumor effects. Our findings suggest a potential therapeutic use for deguelin in patients with triple-negative breast cancer and for those with breast cancers who are sensitive to endocrine- and HER2-targeted therapies. PMID:23348700

  15. The receptor protein tyrosine phosphatase HmLAR1 is up-regulated in the CNS of the adult medicinal leech following injury and is required for neuronal sprouting and regeneration.

    PubMed

    Sethi, Jasmine; Zhao, Bailey; Cuvillier-Hot, Virginie; Boidin-Wichlacz, Céline; Salzet, Michel; Macagno, Eduardo R; Baker, Michael W

    2010-12-01

    LAR-like receptor protein tyrosine phosphatases (RPTPs), which are abundantly expressed in the nervous systems of most if not all bilaterian animals thus far examined, have been implicated in regulating a variety of critical neuronal processes. These include neuronal pathfinding, adhesion and synaptogenesis during development and, in adult mammals, neuronal regeneration. Here we explored a possible role of a LAR-like RPTP (HmLAR1) in response to mechanical trauma in the adult nervous system of the medicinal leech. In situ hybridization and QPCR analyses of HmLAR1 expression in individual segmental ganglia revealed a significant up-regulation in receptor expression following CNS injury, both in situ and following a period in vitro. Furthermore, we observed up-regulation in the expression of the leech homologue of the Abelson tyrosine kinase, a putative signaling partner to LAR receptors, but not among other tyrosine kinases. The effects on neuronal regeneration were assayed by comparing growth across a nerve crush by projections of individual dorsal P neurons (P(D)) following single-cell injection of interfering RNAs against the receptor or control RNAs. Receptor RNAi led to a significant reduction in HmLAR1 expression by the injected cells and resulted in a significant decrease in sprouting and regenerative growth at the crush site relative to controls. These studies extend the role of the HmLARs from leech neuronal development to adult neuronal regeneration and provide a platform to investigate neuronal regeneration and gene regulation at the single cell level. PMID:20708686

  16. The receptor protein tyrosine phosphatase HmLAR1 is up-regulated in the CNS of the adult medicinal leech following injury and is required for neuronal sprouting and regeneration.

    PubMed

    Sethi, Jasmine; Zhao, Bailey; Cuvillier-Hot, Virginie; Boidin-Wichlacz, Céline; Salzet, Michel; Macagno, Eduardo R; Baker, Michael W

    2010-12-01

    LAR-like receptor protein tyrosine phosphatases (RPTPs), which are abundantly expressed in the nervous systems of most if not all bilaterian animals thus far examined, have been implicated in regulating a variety of critical neuronal processes. These include neuronal pathfinding, adhesion and synaptogenesis during development and, in adult mammals, neuronal regeneration. Here we explored a possible role of a LAR-like RPTP (HmLAR1) in response to mechanical trauma in the adult nervous system of the medicinal leech. In situ hybridization and QPCR analyses of HmLAR1 expression in individual segmental ganglia revealed a significant up-regulation in receptor expression following CNS injury, both in situ and following a period in vitro. Furthermore, we observed up-regulation in the expression of the leech homologue of the Abelson tyrosine kinase, a putative signaling partner to LAR receptors, but not among other tyrosine kinases. The effects on neuronal regeneration were assayed by comparing growth across a nerve crush by projections of individual dorsal P neurons (P(D)) following single-cell injection of interfering RNAs against the receptor or control RNAs. Receptor RNAi led to a significant reduction in HmLAR1 expression by the injected cells and resulted in a significant decrease in sprouting and regenerative growth at the crush site relative to controls. These studies extend the role of the HmLARs from leech neuronal development to adult neuronal regeneration and provide a platform to investigate neuronal regeneration and gene regulation at the single cell level.

  17. Pleiotrophin induces neurite outgrowth and up-regulates growth-associated protein (GAP)-43 mRNA through the ALK/GSK3beta/beta-catenin signaling in developing mouse neurons.

    PubMed

    Yanagisawa, Hiroko; Komuta, Yukari; Kawano, Hitoshi; Toyoda, Masashi; Sango, Kazunori

    2010-01-01

    Pleiotrophin (PTN) is highly expressed in the nervous system during embryogenesis; however, little is known about its functional role in neural development. By using whole mount in situ hybridization, we observed that the expression pattern of PTN was similar to that of Wnt3a; PTN mRNA was abundant in the nervous tissue along the dorsal midline and in the forelimb and hindlimb buds of embryonic mice (E8.5-E12.5). Treatment with recombinant PTN (100ng/ml) induced phosphorylation of glycogen synthase kinase 3beta (GSK3beta), nuclear localization of beta-catenin and up-regulation of growth-associated protein (GAP)-43 mRNA in cultured embryonic mouse (E14.5) neurons. Furthermore, recombinant PTN enhanced neurite outgrowth from cortical explants embedded in Matrigel. These PTN-induced biochemical changes and neurite outgrowth were attenuated by the co-treatment with anti-anaplastic lymphoma kinase (ALK) antibodies, but not with anti-protein tyrosine phosphatase (PTP)zeta antibodies. These findings imply that ALK is involved in the PTN signaling on neural development.

  18. Oxytocin Increases Invasive Properties of Endometrial Cancer Cells Through Phosphatidylinositol 3-Kinase/AKT-Dependent Up-Regulation of Cyclooxygenase-1, -2, and X-Linked Inhibitor of Apoptosis Protein1

    PubMed Central

    Déry, Marie-Claude; Chaudhry, Parvesh; Leblanc, Valérie; Parent, Sophie; Fortier, Anne-Marie; Asselin, Eric

    2011-01-01

    Traditionally, oxytocin (OT) is well known to play a crucial role in the regulation of cyclic changes in the uterus, implantation of the embryo, and parturition. Recently, an additional role for OT has been identified in several types of cancer cells in which OT acts as a growth regulator. In endometrial cancer cells, OT is known to efficiently inhibit cellular proliferation. In the present study, we show that OT increases invasiveness of human endometrial carcinoma (HEC) cells, which are otherwise resistant to the growth-inhibiting effects of OT. Using pharmacological inhibitors, invasion assay, RNA interference, and immunofluorescence, we found that OT enhances the invasive properties of HEC cells through up-regulation of X-linked inhibitor of apoptosis protein (XIAP), matrix-metalloproteinase 2 (MMP2), and matrix-metalloproteinase 14 (MMP14). In addition, we show that OT-mediated invasion is both cyclooxygenase 1 (PTGS1) and cyclooxygenase-2 (PTGS2) dependent via the phosphatidylinositol 3-kinase/AKT (PIK3/AKT) pathway. PTGS2 knockdown by shRNA resulted in XIAP down-regulation. We also show that OT receptor is overexpressed in grade I to III endometrial cancer. Taken together, our results describe for the first time a novel role for OT in endometrial cancer cell invasion. PMID:21816851

  19. Protein flexibility: coordinate uncertainties and interpretation of structural differences

    SciTech Connect

    Rashin, Alexander A.; Rashin, Abraham H. L.; Jernigan, Robert L.

    2009-11-01

    Criteria for the interpretability of coordinate differences and a new method for identifying rigid-body motions and nonrigid deformations in protein conformational changes are developed and applied to functionally induced and crystallization-induced conformational changes. Valid interpretations of conformational movements in protein structures determined by X-ray crystallography require that the movement magnitudes exceed their uncertainty threshold. Here, it is shown that such thresholds can be obtained from the distance difference matrices (DDMs) of 1014 pairs of independently determined structures of bovine ribonuclease A and sperm whale myoglobin, with no explanations provided for reportedly minor coordinate differences. The smallest magnitudes of reportedly functional motions are just above these thresholds. Uncertainty thresholds can provide objective criteria that distinguish between true conformational changes and apparent ‘noise’, showing that some previous interpretations of protein coordinate changes attributed to external conditions or mutations may be doubtful or erroneous. The use of uncertainty thresholds, DDMs, the newly introduced CDDMs (contact distance difference matrices) and a novel simple rotation algorithm allows a more meaningful classification and description of protein motions, distinguishing between various rigid-fragment motions and nonrigid conformational deformations. It is also shown that half of 75 pairs of identical molecules, each from the same asymmetric crystallographic cell, exhibit coordinate differences that range from just outside the coordinate uncertainty threshold to the full magnitude of large functional movements. Thus, crystallization might often induce protein conformational changes that are comparable to those related to or induced by the protein function.

  20. Decreased Amounts of Cell Wall-Associated Protein A and Fibronectin-Binding Proteins in Staphylococcus aureus sarA Mutants due to Up-Regulation of Extracellular Proteases

    PubMed Central

    Karlsson, Anna; Saravia-Otten, Patricia; Tegmark, Karin; Morfeldt, Eva; Arvidson, Staffan

    2001-01-01

    Data have been presented indicating that Staphylococcus aureus cell surface protein can be degraded by extracellular proteases produced by the same bacterium. We have found that in sarA mutant cells, which produce high amounts of four major extracellular proteases (staphylococcal serine protease [V8 protease] [SspA], cysteine protease [SspB], aureolysin [metalloprotease] [Aur], and staphopain [Scp]), the levels of cell-bound fibronectin-binding proteins (FnBPs) and protein A were very low compared to those of wild-type cells, in spite of unaltered or increased transcription of the corresponding genes. Cultivation of sarA mutant cells in the presence of the global protease inhibitor α2-macroglobulin resulted in a 16-fold increase in cell-bound FnBPs, indicating that extracellular proteases were responsible for the decreased amounts of FnBPs in sarA mutant cells. The protease inhibitor E64 had no effect on the level of FnBPs, indicating that cysteine proteases were not involved. Inactivation of either ssp or aur in the prototype S. aureus strain 8325-4 resulted in a threefold increase in the amount of cell-bound FnBPs. Inactivation of the same protease genes in a sarA mutant of 8325-4 resulted in a 10- to 20-fold increase in cell-bound protein A. As the serine protease requires aureolysin to be activated, it can thus be concluded that the serine protease is the most important protease in the release of cell-bound FnBPs and protein A. PMID:11447146

  1. Coordination of Protein Phosphorylation and Dephosphorylation in Synaptic Plasticity.

    PubMed

    Woolfrey, Kevin M; Dell'Acqua, Mark L

    2015-11-27

    A central theme in nervous system function is equilibrium: synaptic strengths wax and wane, neuronal firing rates adjust up and down, and neural circuits balance excitation with inhibition. This push/pull regulatory theme carries through to the molecular level at excitatory synapses, where protein function is controlled through phosphorylation and dephosphorylation by kinases and phosphatases. However, these opposing enzymatic activities are only part of the equation as scaffolding interactions and assembly of multi-protein complexes are further required for efficient, localized synaptic signaling. This review will focus on coordination of postsynaptic serine/threonine kinase and phosphatase signaling by scaffold proteins during synaptic plasticity.

  2. ClC-3 Chloride Channel Proteins Regulate the Cell Cycle by Up-regulating cyclin D1-CDK4/6 through Suppressing p21/p27 Expression in Nasopharyngeal Carcinoma Cells

    PubMed Central

    Ye, Dong; Luo, Hai; Lai, Zhouyi; Zou, Lili; Zhu, Linyan; Mao, Jianwen; Jacob, Tim; Ye, Wencai; Wang, Liwei; Chen, Lixin

    2016-01-01

    It was shown in this study that knockdown of ClC-3 expression by ClC-3 siRNA prevented the activation of hypotonicity-induced chloride currents, and arrested cells at the G0/G1 phase in nasopharyngeal carcinoma CNE-2Z cells. Reconstitution of ClC-3 expression with ClC-3 expression plasmids could rescue the cells from the cell cycle arrest caused by ClC-3 siRNA treatments. Transfection of cells with ClC-3 siRNA decreased the expression of cyclin D1, cyclin dependent kinase 4 and 6, and increased the expression of cyclin dependent kinase inhibitors (CDKIs), p21 and p27. Pretreatments of cells with p21 and p27 siRNAs depleted the inhibitory effects of ClC-3 siRNA on the expression of CDK4 and CDK6, but not on that of cyclin D1, indicating the requirement of p21 and p27 for the inhibitory effects of ClC-3 siRNA on CDK4 and CDK6 expression. ClC-3 siRNA inhibited cells to progress from the G1 phase to the S phase, but pretreatments of cells with p21 and p27 siRNAs abolished the inhibitory effects of ClC-3 siRNA on the cell cycle progress. Our data suggest that ClC-3 may regulate cell cycle transition between G0/G1 and S phases by up-regulation of the expression of CDK4 and CDK6 through suppression of p21 and p27 expression. PMID:27451945

  3. FRZB up-regulated in hepatocellular carcinoma bone metastasis

    PubMed Central

    Huang, Jia; Hu, Wenhao; Lin, Xiangjin; Wang, Xuanwei; Jin, Ketao

    2015-01-01

    The clinical relevance of frizzled-related protein (FRZB) in hepatocellular carcinoma (HCC) bone metastasis remains uncertain. The aim of this study was to assess the clinical relationship of FRZB in patients with HCC bone metastasis after surgical resection. FRZB expression was evaluated by immunohistochemistry in formalin-fixed paraffin embedded (FFPE) HCC and paired bone metastasis tissues from 13 patients that underwent surgical resection. The clinical characteristics of 13 HCC patients with synchronous or metachronous bone metastasis received surgery were retrospectively reviewed. We found that FRZB was positive in 9 HCC tissues (69.2%) and in 11 paired bone metastatic tissues (84.6%) among these 13 paired samples. The expression of FRZB in the bone metastases was noticeably higher than that in the paired HCC tissues. The expression of FRZB was up-regulated in 10 (76.9%) paired bone metastases tissues. FRZB expression was up-regulated in HCC bone metastasis tissue, which suggested that FRZB might play a key role in the HCC bone metastasis. PMID:26722540

  4. The proapoptotic protein Bim is up regulated by 1α,25-dihydroxyvitamin D3 and its receptor agonist in endothelial cells and transformed by viral GPCR associated to Kaposi sarcoma.

    PubMed

    Suares, Alejandra; Russo de Boland, Ana; Verstuyf, Annemieke; Boland, Ricardo; González-Pardo, Verónica

    2015-10-01

    We have previously shown that 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3] and its less calcemic analog TX 527 induce apoptosis via caspase-3 activation in endothelial cells (SVEC) and endothelial cells transformed by the viral G protein-coupled receptor associated to Kaposi sarcoma (vGPCR). In this work, we studied whether intrinsic apoptotic pathway could be activated by changing the balance between anti and pro-apoptotic proteins. Time response qRT-PCR analysis demonstrated that the mRNA level of anti-apoptotic gene Bcl-2 decreased after 12h and increased after 48h treatment with 1α,25(OH)2D3 or TX 527 in SVEC and vGPCR cells, whereas its protein level remained unchanged through time. mRNA levels of pro-apoptotic gene Bax significantly increased only in SVEC after 24 and 48h treatment with 1α,25(OH)2D3 and TX 527 although its protein levels remained unchanged in both cell lines. Bim mRNA and protein levels increased in SVEC and vGPCR cells. Bim protein increase by 1α,25(OH)2D3 and TX 527 was abolished when the expression of vitamin D receptor (VDR) was suppressed. On the other hand, Bortezomib (0.25-1nM), an inhibitor of NF-κB pathway highly activated in vGPCR cells, increased Bim protein levels and induced caspase-3 cleavage. Altogether, these results indicate that 1α,25(OH)2D3 and TX 527 trigger apoptosis by Bim protein increase which turns into the activation of caspase-3 in SVEC and vGPCR cells. Moreover, this effect is mediated by VDR and involves NF-κB pathway inhibition in vGPCR.

  5. Prediction of coordination number and relative solvent accessibility in proteins.

    PubMed

    Pollastri, Gianluca; Baldi, Pierre; Fariselli, Pietro; Casadio, Rita

    2002-05-01

    Knowing the coordination number and relative solvent accessibility of all the residues in a protein is crucial for deriving constraints useful in modeling protein folding and protein structure and in scoring remote homology searches. We develop ensembles of bidirectional recurrent neural network architectures to improve the state of the art in both contact and accessibility prediction, leveraging a large corpus of curated data together with evolutionary information. The ensembles are used to discriminate between two different states of residue contacts or relative solvent accessibility, higher or lower than a threshold determined by the average value of the residue distribution or the accessibility cutoff. For coordination numbers, the ensemble achieves performances ranging within 70.6-73.9% depending on the radius adopted to discriminate contacts (6A-12A). These performances represent gains of 16-20% over the baseline statistical predictor, always assigning an amino acid to the largest class, and are 4-7% better than any previous method. A combination of different radius predictors further improves performance. For accessibility thresholds in the relevant 15-30% range, the ensemble consistently achieves a performance above 77%, which is 10-16% above the baseline prediction and better than other existing predictors, by up to several percentage points. For both problems, we quantify the improvement due to evolutionary information in the form of PSI-BLAST-generated profiles over BLAST profiles. The prediction programs are implemented in the form of two web servers, CONpro and ACCpro, available at http://promoter.ics.uci.edu/BRNN-PRED/.

  6. Parallel up-regulation of the profilin gene family following independent domestication of diploid and allopolyploid cotton (Gossypium).

    PubMed

    Bao, Ying; Hu, Guanjing; Flagel, Lex E; Salmon, Armel; Bezanilla, Magdalena; Paterson, Andrew H; Wang, Zining; Wendel, Jonathan F

    2011-12-27

    Cotton is remarkable among our major crops in that four species were independently domesticated, two allopolyploids and two diploids. In each case thousands of years of human selection transformed sparsely flowering, perennial shrubs into highly productive crops with seeds bearing the vastly elongated and abundant single-celled hairs that comprise modern cotton fiber. The genetic underpinnings of these transformations are largely unknown, but comparative gene expression profiling experiments have demonstrated up-regulation of profilin accompanying domestication in all three species for which wild forms are known. Profilins are actin monomer binding proteins that are important in cytoskeletal dynamics and in cotton fiber elongation. We show that Gossypium diploids contain six profilin genes (GPRF1-GPRF6), located on four different chromosomes (eight chromosomes in the allopolyploid). All but one profilin (GPRF6) are expressed during cotton fiber development, and both homeologs of GPRF1-GPRF5 are expressed in fibers of the allopolyploids. Remarkably, quantitative RT-PCR and RNAseq data demonstrate that GPRF1-GPRF5 are all up-regulated, in parallel, in the three independently domesticated cottons in comparison with their wild counterparts. This result was additionally supported by iTRAQ proteomic data. In the allopolyploids, there This usage of novel should be fine, since it refers to a novel evolutionary process, not a novel discovery has been novel recruitment of the sixth profilin gene (GPRF6) as a result of domestication. This parallel up-regulation of an entire gene family in multiple species in response to strong directional selection is without precedent and suggests unwitting selection on one or more upstream transcription factors or other proteins that coordinately exercise control over profilin expression. PMID:22160709

  7. Baicalein prevents 6-hydroxydopamine-induced mitochondrial dysfunction in SH-SY5Y cells via inhibition of mitochondrial oxidation and up-regulation of DJ-1 protein expression.

    PubMed

    Wang, Yue-Hua; Yu, Hai-Tao; Pu, Xiao-Ping; Du, Guan-Hua

    2013-01-01

    Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive loss of dopaminergic (DA) neurons at the substantia nigra. Mitochondrial dysfunction is involved in the mechanism of cell damage in Parkinson's disease (PD). 6-Hydroxydopamine (6-OHDA) is a dopamine analog which specifically damages dopaminergic neurons. Baicalein has been previously reported to have potential in the treatment of PD. The purpose of the present study was to investigate the mechanism of action of baicalein against 6-OHDA injury in SH-SY5Y cells. The results showed that baicalein significantly alleviated alterations of mitochondrial redox activity and mitochondrial membrane potential induced by 6-OHDA in a dose-dependent manner in SH-SY5Y cells compared with vehicle group. Futhermore, baicalein decreased the production of ROS and upregulated the DJ-1 protein expression in SH-SY5Y cells. In addition, baicalein also inhibited ROS production and lipid peroxidation (IC50 = 6.32 ± 0.03 μM) in rat brain mitochondia. In summary, the underlying mechanisms of baicalein against 6-OHDA-induced mitochondrial dysfunction may involve inhibition of mitochondrial oxidation and upregulation of DJ-1 protein expression. PMID:24288000

  8. Lipopolysaccharides (LPS), up-regulate the IL-1-mRNA and down-regulate the glial fibrillary acidic protein (GFAP) and glutamine synthetase (GS)-mRNAs in astroglial primary cultures.

    PubMed

    Letournel-Boulland, M L; Fages, C; Rolland, B; Tardy, M

    1994-01-01

    The effect of lipopolysaccharides (LPS), a component of gram-negative bacteria, has been studied in both exponentially growing and confluent morphologically differentiated astroglial cells in primary cultures. The expression of glial fibrillary acidic protein (GFAP) and Glutamine Synthetase (GS) were investigated in parallel with proliferation and expression of IL-1 beta-mRNA. During the exponential growth, proliferation was severely inhibited by LPS. The effect was time- and dose-dependent. On confluent differentiated cells LPS induced an inhibition of cell proliferation which was associated with a down-regulation of GFAP-mRNA, GS-mRNA and GS expressions and with a transitory increase in IL-1 beta mRNA expression. The observed effects might interact with the astroglial developmental program and with the astroglial function.

  9. Increased Mitochondrial Pro-oxidant Activity Mediates Up-regulation of Complex I S-glutathionylation via Protein Thiyl Radical in the Murine Heart of eNOS−/−

    PubMed Central

    Kang, Patrick T.; Chen, Chwen-Lih; Chen, Yeong-Renn

    2014-01-01

    In response to oxidative stress, mitochondrial Complex I is reversibly S-glutathionylated. We hypothesized that protein S-glutathionylation (PrSSG) of Complex I is mediated by a kinetic mechanism involving reactive protein thiyl radical (PrS•) and GSH in vivo. Previous studies have shown that in vitro S-glutathionylation of isolated Complex I at the 51 kDa and 75 kDa subunits was detected under the conditions of •O2− production, and mass spectrometry confirmed that formation of Complex I PrS• mediates PrSSG. Exposure of myocytes to menadione resulted in enhanced Complex I PrSSG and PrS• (Kang et al Free Radical Biol. Med. 2012; 52: 962–73). In this investigation, we tested our hypothesis in the murine heart of eNOS−/−. The eNOS−/− mouse is known to be hypertensive and develops the pathological phenotype of progressive cardiac hypertrophy. The mitochondria isolated from the eNOS−/− myocardium exhibited a marked dysfunction with impaired state 3 respiration, a declining respiratory control index, and decreasing enzymatic activities of ETC components. Further biochemical analysis and EPR measurement indicated defective aconitase activity, a marked increase in •O2− generation activity, and a more oxidized physiological setting. These results suggest increasing prooxidant activity and subsequent oxidative stress in the mitochondria of the eNOS−/− murine heart. When Complex I from the mitochondria of the eNOS−/− murine heart was analyzed by immuno-spin trapping and probed with anti-GSH antibody, both PrS• and PrSSG of Complex I were significantly enhanced. Overexpression of SOD2 in the murine heart dramatically diminished the detected PrS•, supporting the conclusion that mediation of Complex I PrSSG by oxidative stress-induced PrS• is a unique pathway for the redox regulation of mitochondrial function in vivo. PMID:25445401

  10. Cytoprotective effect of Podophyllum hexandrum against gamma radiation is mediated via hemopoietic system stimulation and up-regulation of heme-oxygenase-1 and the prosurvival multidomain protein Bcl-2.

    PubMed

    Rajesh, Arora; Sagar, R; Singh, S; Kumar, R; Sharma, A K; Prasad, J; Singh, S; Gupta, M; Sharma, R K; Puri, S C; Krishna, B; Siddiqui, M S; Lahiri, S S; Tripathi, R P; Qazi, G N

    2007-03-01

    The radioprotective effect of a hydroalcoholic extracted material (REC-2000) from the rhizome of Podophyllum hexandrum was studied in mice exposed to lethal gamma radiation (10 Gy). The extract (REC-2000) was found to restore the hemoglobin content (14.73 +/- 0.33) and total leukocyte count (TLC) (4166.66 +/- 0.02) in lethally (10 Gy) gamma-irradiated mice on the 15th day in comparison to the radiation control mice. The hemoglobin content of the drug + radiation group was observed to be significantly (21.25%) higher than the radiation control group on the 10th day. Similarly, the TLC was significantly increased (83.33 times) in the drug + radiation group as compared to a radiation (10 Gy) only group on the 10th day. Enhanced expression of heme-oxygenase-1 and Bcl-2 protein observed by Western blotting further supports the observation of hemopoietic recovery in irradiated mice. These findings indicate that the bioactive constituents present in REC-2000 exert the radioprotective effect by modulating the hemopoietic system.

  11. An Arabidopsis WDR protein coordinates cellular networks involved in light, stress response and hormone signals.

    PubMed

    Chuang, Huey-Wen; Feng, Ji-Huan; Feng, Yung-Lin; Wei, Miam-Ju

    2015-12-01

    The WD-40 repeat (WDR) protein acts as a scaffold for protein interactions in various cellular events. An Arabidopsis WDR protein exhibited sequence similarity with human WDR26, a scaffolding protein implicated in H2O2-induced cell death in neural cells. The AtWDR26 transcript was induced by auxin, abscisic acid (ABA), ethylene (ET), osmostic stress and salinity. The expression of AtWDR26 was regulated by light, and seed germination of the AtWDR26 overexpression (OE) and seedling growth of the T-DNA knock-out (KO) exhibited altered sensitivity to light. Root growth of the OE seedlings increased tolerance to ZnSO4 and NaCl stresses and were hypersensitive to inhibition of osmotic stress. Seedlings of OE and KO altered sensitivities to multiple hormones. Transcriptome analysis of the transgenic plants overexpressing AtWDR26 showed that genes involved in the chloroplast-related metabolism constituted the largest group of the up-regulated genes. AtWDR26 overexpression up-regulated a large number of genes related to defense cellular events including biotic and abiotic stress response. Furthermore, several members of genes functioning in the regulation of Zn homeostasis, and hormone synthesis and perception of auxin and JA were strongly up-regulated in the transgenic plants. Our data provide physiological and transcriptional evidence for AtWDR26 role in hormone, light and abiotic stress cellular events.

  12. Functional inactivation of CXC chemokine receptor 4-mediated responses through SOCS3 up-regulation.

    PubMed

    Soriano, Silvia F; Hernanz-Falcón, Patricia; Rodríguez-Frade, José Miguel; De Ana, Ana Martín; Garzón, Ruth; Carvalho-Pinto, Carla; Vila-Coro, Antonio J; Zaballos, Angel; Balomenos, Dimitrios; Martínez-A, Carlos; Mellado, Mario

    2002-08-01

    Hematopoietic cell growth, differentiation, and chemotactic responses require coordinated action between cytokines and chemokines. Cytokines promote receptor oligomerization, followed by Janus kinase (JAK) kinase activation, signal transducers and transactivators of transcription (STAT) nuclear translocation, and transcription of cytokine-responsive genes. These include genes that encode a family of negative regulators of cytokine signaling, the suppressors of cytokine signaling (SOCS) proteins. After binding their specific receptors, chemokines trigger receptor dimerization and activate the JAK/STAT pathway. We show that SOCS3 overexpression or up-regulation, stimulated by a cytokine such as growth hormone, impairs the response to CXCL12, measured by Ca(2+) flux and chemotaxis in vitro and in vivo. This effect is mediated by SOCS3 binding to the CXC chemokine receptor 4 receptor, blocking JAK/STAT and Galpha(i) pathways, without interfering with cell surface chemokine receptor expression. The data provide clear evidence for signaling cross-talk between cytokine and chemokine responses in building a functional immune system.

  13. Cotton Benzoquinone Reductase: Up-regulation During Early Cotton Fiber Developement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Benzoquinone reductase (BR; EC 1.6.5.7) is an enzyme that catalyzes the bivalent redox reactions of quinones without the production of free radical intermediates. Using 2-D PAGE comparisons, two proteins were found to be up-regulated in wild-type cotton ovules during the fiber initiation stage but ...

  14. A plant gene up-regulated at rust infection sites.

    PubMed

    Ayliffe, Michael A; Roberts, James K; Mitchell, Heidi J; Zhang, Ren; Lawrence, Gregory J; Ellis, Jeffrey G; Pryor, Tony J

    2002-05-01

    Expression of the fis1 gene from flax (Linum usitatissimum) is induced by a compatible rust (Melampsora lini) infection. Infection of transgenic plants containing a beta-glucuronidase (GUS) reporter gene under the control of the fis1 promoter showed that induction is highly localized to those leaf mesophyll cells within and immediately surrounding rust infection sites. The level of induction reflects the extent of fungal growth. In a strong resistance reaction, such as the hypersensitive fleck mediated by the L6 resistance gene, there is very little fungal growth and a microscopic level of GUS expression. Partially resistant flax leaves show levels of GUS expression that were intermediate to the level observed in the fully susceptible infection. Sequence and deletion analysis using both transient Agrobacterium tumefaciens expression and stable transformation assays have shown that the rust-inducible fis1 promoter is contained within a 580-bp fragment. Homologs of fis1 were identified in expressed sequence tag databases of a range of plant species including dicots, monocots, and a gymnosperm. Homologous genes isolated from maize (Zea mays; mis1), barley (Hordeum vulgare; bis1), wheat (Triticum aestivum; wis1), and Arabidopsis encode proteins that are highly similar (76%-82%) to the FIS1 protein. The Arabidopsis homologue has been reported to encode a delta1-pyrroline-5-carboxylate dehydrogenase that is involved in the catabolism of proline to glutamate. RNA-blot analysis showed that mis1 in maize and the bis1 homolog in barley are both up-regulated by a compatible infection with the corresponding species-specific rust. The rust-induced genes homologous to fis1 are present in many plants. The promoters of these genes have potential roles for the engineering of synthetic rust resistance genes by targeting transgene expression to the sites of rust infection.

  15. CRASP: a program for analysis of coordinated substitutions in multiple alignments of protein sequences.

    PubMed

    Afonnikov, Dmitry A; Kolchanov, Nikolay A

    2004-07-01

    Recent results suggest that during evolution certain substitutions at protein sites may occur in a coordinated manner due to interactions between amino acid residues. Information on these coordinated substitutions may be useful for analysis of protein structure and function. CRASP is an Internet-available software tool for the detection and analysis of coordinated substitutions in multiple alignments of protein sequences. The approach is based on estimation of the correlation coefficient between the values of a physicochemical parameter at a pair of positions of sequence alignment. The program enables the user to detect and analyze pairwise relationships between amino acid substitutions at protein sequence positions, estimate the contribution of the coordinated substitutions to the evolutionary invariance or variability in integral protein physicochemical characteristics such as the net charge of protein residues and hydrophobic core volume. The CRASP program is available at http://wwwmgs.bionet.nsc.ru/mgs/programs/crasp/.

  16. A Novel Systems-Biology Algorithm for the Analysis of Coordinated Protein Responses Using Quantitative Proteomics.

    PubMed

    García-Marqués, Fernando; Trevisan-Herraz, Marco; Martínez-Martínez, Sara; Camafeita, Emilio; Jorge, Inmaculada; Lopez, Juan Antonio; Méndez-Barbero, Nerea; Méndez-Ferrer, Simón; Del Pozo, Miguel Angel; Ibáñez, Borja; Andrés, Vicente; Sánchez-Madrid, Francisco; Redondo, Juan Miguel; Bonzon-Kulichenko, Elena; Vázquez, Jesús

    2016-05-01

    The coordinated behavior of proteins is central to systems biology. However, the underlying mechanisms are poorly known and methods to analyze coordination by conventional quantitative proteomics are still lacking. We present the Systems Biology Triangle (SBT), a new algorithm that allows the study of protein coordination by pairwise quantitative proteomics. The Systems Biology Triangle detected statistically significant coordination in diverse biological models of very different nature and subjected to different kinds of perturbations. The Systems Biology Triangle also revealed with unprecedented molecular detail an array of coordinated, early protein responses in vascular smooth muscle cells treated at different times with angiotensin-II. These responses included activation of protein synthesis, folding, turnover, and muscle contraction - consistent with a differentiated phenotype-as well as the induction of migration and the repression of cell proliferation and secretion. Remarkably, the majority of the altered functional categories were protein complexes, interaction networks, or metabolic pathways. These changes could not be detected by other algorithms widely used by the proteomics community, and the vast majority of proteins involved have not been described before to be regulated by AngII. The unique capabilities of The Systems Biology Triangle to detect functional protein alterations produced by the coordinated action of proteins in pairwise quantitative proteomics experiments make this algorithm an attractive choice for the biological interpretation of results on a routine basis.

  17. Nutraceutical up-regulation of serotonin paradoxically induces compulsive behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The role of diet in either the etiology or treatment of complex mental disorder is highly controversial in psychiatry. However, physiological mechanisms by which diet can influence brain chemistry – particularly that of serotonin – are well established. Here we show that dietary up-regulation of br...

  18. MicroRNA-34a induces a senescence-like change via the down-regulation of SIRT1 and up-regulation of p53 protein in human esophageal squamous cancer cells with a wild-type p53 gene background.

    PubMed

    Ye, Zhimin; Fang, Jun; Dai, Shujun; Wang, Yuezhen; Fu, Zhenfu; Feng, Wei; Wei, Qichun; Huang, Pintong

    2016-01-28

    MiR-34a has been reported as a non-coding RNA universally expressed in normal old cells and a probable suppressor of diverse cancer cells; however, this miRNA's expression and anti-tumor mechanism in esophageal squamous cancer cells (ESCC) remains unclear. We explored these questions in three human ESCC lines, KYSE-450, KYSE-410, and ECa-109, with wild-type p53 and mutant p53 backgrounds. Through a specific stem-loop RT primer for miR-34a, we examined the relevant expression level of miR-34a in these three cell lines using real-time reverse transcription PCR (qRT-PCR). We found that the expression level of miR-34a induced by the DNA damage agent adrmycin (ADR) was both p53- and time-dependent. Following incubation with miR-34a, cellular growth inhibition was exhibited differently in the three cell lines harbored with different p53 backgrounds. Furthermore, the MTT assay demonstrated an miR-34a-related cytotoxic effect in cell growth. Senescence-associated β-galactosidase (SA-β-Gal) staining was used to examine senescence-like phenotypes induced by miR-34a. Mechanistic investigation suggested that the down-regulation of Sirtuin1 (SIRT1) and up-regulation of p53/p21 contributed to the anti-tumor mechanism of miR-34a in wild-type p53 ECa-109 cells, while neither of the apoptosis-related proteins PARP and caspase-3 caused significant changes. In summary, our findings indicated that the intrinsic expression of miR-34a was relatively low and was expressed differently among different p53 backgrounds and ADR treatment times. The anti-tumor effect of miR-34a was primarily dependent on the regulation of SIRT1 and p53/p21 protein, not apoptosis-associated proteins.

  19. Neuropilin 1 Receptor Is Up-Regulated in Dysplastic Epithelium and Oral Squamous Cell Carcinoma.

    PubMed

    Shahrabi-Farahani, Shokoufeh; Gallottini, Marina; Martins, Fabiana; Li, Erik; Mudge, Dayna R; Nakayama, Hironao; Hida, Kyoko; Panigrahy, Dipak; D'Amore, Patricia A; Bielenberg, Diane R

    2016-04-01

    Neuropilins are receptors for disparate ligands, including proangiogenic factors such as vascular endothelial growth factor and inhibitory class 3 semaphorin (SEMA3) family members. Differentiated cells in skin epithelium and cutaneous squamous cell carcinoma highly express the neuropilin-1 (NRP1) receptor. We examined the expression of NRP1 in human and mouse oral mucosa. NRP1 was significantly up-regulated in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). NRP1 receptor localized to the outer suprabasal epithelial layers in normal tongue, an expression pattern similar to the normal skin epidermis. However, dysplastic tongue epithelium and OSCC up-regulated NRP1 in basal and proliferating epithelial layers, a profile unseen in cutaneous squamous cell carcinoma. NRP1 up-regulation is observed in a mouse carcinogen-induced OSCC model and in human tongue OSCC biopsies. Human OSCC cell lines express NRP1 protein in vitro and in mouse tongue xenografts. Sites of capillary infiltration into orthotopic OSCC tumors correlate with high NRP1 expression. HSC3 xenografts, which express the highest NRP1 levels of the cell lines examined, showed massive intratumoral lymphangiogenesis. SEMA3A inhibited OSCC cell migration, suggesting that the NRP1 receptor was bioactive in OSCC. In conclusion, NRP1 is regulated in the oral epithelium and is selectively up-regulated during epithelial dysplasia. NRP1 may function as a reservoir to sequester proangiogenic ligands within the neoplastic compartment, thereby recruiting neovessels toward tumor cells. PMID:26877262

  20. CD84 is markedly up-regulated in Kawasaki disease arteriopathy

    PubMed Central

    Reindel, R; Bischof, J; Kim, K-Y A; Orenstein, J M; Soares, M B; Baker, S C; Shulman, S T; Perlman, E J; Lingen, M W; Pink, A J; Trevenen, C; Rowley, A H

    2014-01-01

    The major goals of Kawasaki disease (KD) therapy are to reduce inflammation and prevent thrombosis in the coronary arteries (CA), but some children do not respond to currently available non-specific therapies. New treatments have been difficult to develop because the molecular pathogenesis is unknown. In order to identify dysregulated gene expression in KD CA, we performed high-throughput RNA sequencing on KD and control CA, validated potentially dysregulated genes by real-time reverse transcription–polymerase chain reaction (RT–PCR) and localized protein expression by immunohistochemistry. Signalling lymphocyte activation molecule CD84 was up-regulated 16-fold (P < 0·01) in acute KD CA (within 2 months of onset) and 32-fold (P < 0·01) in chronic CA (5 months to years after onset). CD84 was localized to inflammatory cells in KD tissues. Genes associated with cellular proliferation, motility and survival were also up-regulated in KD CA, and immune activation molecules MX2 and SP140 were up-regulated in chronic KD. CD84, which facilitates immune responses and stabilizes platelet aggregates, is markedly up-regulated in KD CA in patients with acute and chronic arterial disease. We provide the first molecular evidence of dysregulated inflammatory responses persisting for months to years in CA significantly damaged by KD. PMID:24635044

  1. Cotton Benzoquinon Reductase: Up-Regulation During Early Fiber Development and Heterologous Expresson and Characterization in Pichia Pastoris

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Benzoquinone reductase (BR) is an enzyme which catalyzes the bivalent redox reactions of quinones without the production of free radical intermediates. Using 2-D PAGE, two proteins were found to be up-regulated in wild-type cotton ovules during the fiber initiation stage. These proteins were excis...

  2. Perlecan up-regulation of FRNK suppresses smooth muscle cell proliferation via inhibition of FAK signaling.

    PubMed

    Walker, Heather A; Whitelock, John M; Garl, Pamela J; Nemenoff, Raphael A; Stenmark, Kurt R; Weiser-Evans, Mary C M

    2003-05-01

    We previously reported that fully assembled basement membranes are nonpermissive to smooth muscle cell (SMC) replication and that perlecan (PN), a basement membrane heparan sulfate proteoglycan, is a dominant effector of this response. We report here that SMC adhesion to basement membranes, and perlecan in particular, up-regulate the expression of focal adhesion kinase-related nonkinase (FRNK), a SMC-specific endogenous inhibitor of FAK, which subsequently suppresses FAK-mediated, ERK1/2-dependent growth signals. Up-regulation of FRNK by perlecan is actively and continuously regulated. Relative to the matrix proteins studied, the effects are unique to perlecan, because plating of SMCs on several other basement membrane proteins is associated with low levels of FRNK and corresponding high levels of FAK and ERK1/2 phosphorylation and SMC growth. Perlecan supports SMC adhesion, although there is reduced cell spreading compared with fibronectin (FN), laminin (LN), or collagen type IV (IV). Despite the reduction in cell spreading, we report that perlecan-induced up-regulation of FRNK is independent of cell shape changes. Growth inhibition by perlecan was rescued by overexpressing a constitutively active FAK construct, but overexpressing kinase-inactivated mutant FAK or FRNK attenuated fibronectin-stimulated growth. These data indicate that perlecan functions as an endogenously produced inhibitor of SMC growth at least in part through the active regulation of FRNK expression. FRNK, in turn, may control SMC growth by downregulating FAK-dependent signaling events.

  3. A20 is up-regulated in primary mouse hepatocytes subjected to hypoxia and reperfusion.

    PubMed

    Sun, Jiao; Sun, Luning; Zhang, Ning; Lu, Xiaomei; Zhang, Haipeng

    2012-12-01

    Hepatic ischemia reperfusion-induced injury is a major medical concern, and it is important to characterize the adaptive mechanisms of hepatocytes to hypoxia and reoxygenation to sustain liver function. In this study, we reported a proteomic analysis of ischemia reperfusion-induced global responses in primary hepatocytes. The primary hepatocytes were isolated from mice and exposed to oxygen to mimic ischemia reperfusion. Total proteins were extracted from the cells and analyzed by two-dimensional gel electrophoresis followed by matrix-assisted laser desorption time-of-flight mass spectrometry. Zinc finger protein A20, mercaptopyruvate sulfur transferase, apolipoprotein E precursor and carbamoyl-phosphate synthase mitochondrial precursor were identified as differentially expressed in differently exposed groups. Reverse transcriptase polymerase chain reaction and Western blot analysis validated that A20 was significantly up-regulated in the hepatocytes subjected to hypoxia and reperfusion. In addition, the expression of peroxisome proliferator-activated receptor α, an A20 target, was up-regulated in the hepatocytes subjected to hypoxia and reperfusion. Our results on A20 provide new insight into the mechanism underlying the adaptation of hepatocytes to hypoxia and reperfusion. Because of its role in the up-regulation of peroxisome proliferator-activated receptor α expression to protect hepatocytes from reperfusion-induced apoptosis, A20 is a potential target for the prevention and therapy of liver injury after ischemia reperfusion.

  4. Leptin up-regulates the lactogenic effect of prolactin in the bovine mammary gland in vitro.

    PubMed

    Feuermann, Y; Shamay, A; Mabjeesh, S J

    2008-11-01

    The ability of leptin to up-regulate prolactin action in the mammary gland is well established. We examined the effect of leptin and prolactin on traits associated with lactation. Leptin and prolactin enhanced proliferation (thymidine incorporation) of the mammary gland cells, elevated the cells' proliferation in a dose-responsive manner, and synergized to elevate the expression of amino acid metabolism via a 90% increase in aminopeptidase N expression. Leptin and prolactin decreased apoptosis (decreased caspase-3 expression by 60%) in the same manner. Leptin enhanced the effect of prolactin on all of these processes in bovine mammary explants. Leptin and prolactin regulated mTOR (mammalian target of rapamycin) by increasing expression by 66%, which is one of the signal-transduction junctions involved in the regulation of proliferation, apoptosis, and protein synthesis. These findings support the hypothesis that leptin up-regulates prolactin action in the bovine mammary gland. PMID:18946122

  5. Rosiglitazone ameliorates diffuse axonal injury by reducing loss of tau and up-regulating caveolin-1 expression

    PubMed Central

    Zhao, Yong-lin; Song, Jin-ning; Ma, Xu-dong; Zhang, Bin-fei; Li, Dan-dong; Pang, Hong-gang

    2016-01-01

    Rosiglitazone up-regulates caveolin-1 levels and has neuroprotective effects in both chronic and acute brain injury. Therefore, we postulated that rosiglitazone may ameliorate diffuse axonal injury via its ability to up-regulate caveolin-1, inhibit expression of amyloid-beta precursor protein, and reduce the loss and abnormal phosphorylation of tau. In the present study, intraperitoneal injection of rosiglitazone significantly reduced the levels of amyloid-beta precursor protein and hyperphosphorylated tau (phosphorylated at Ser404(p-tau (S404)), and it increased the expression of total tau and caveolin-1 in the rat cortex. Our results show that rosiglitazone inhibits the expression of amyloid-beta precursor protein and lowers p-tau (S404) levels, and it reduces the loss of total tau, possibly by up-regulating caveolin-1. These actions of rosiglitazone may underlie its neuroprotective effects in the treatment of diffuse axonal injury. PMID:27482223

  6. The dynamics of zinc sites in proteins: electronic basis for coordination sphere expansion at structural sites.

    PubMed

    Daniel, A Gerard; Farrell, Nicholas P

    2014-12-01

    The functional role assumed by zinc in proteins is closely tied to the variable dynamics around its coordination sphere arising by virtue of its flexibility in bonding. Modern experimental and computational methods allow the detection and study of previously unknown features of bonding between zinc and its ligands in protein environment. These discoveries are occurring just in time as novel biological functions of zinc, which involve rather unconventional coordination trends, are emerging. In this sense coordination sphere expansion of structural zinc sites, as observed in our previous experiments, is a novel phenomenon. Here we explore the electronic and structural requirements by simulating this phenomenon in structural zinc sites using DFT computations. For this purpose, we have chosen MPW1PW91 and a mixed basis set combination as the DFT method through benchmarking, because it accurately reproduces structural parameters of experimentally characterized zinc compounds. Using appropriate models, we show that the greater ionic character of zinc coordination would allow for coordination sphere expansion if the steric and electrostatic repulsions of the ligands are attenuated properly. Importantly, through the study of electronic and structural aspects of the models used, we arrive at a comprehensive bonding model, explaining the factors that influence coordination of zinc in proteins. The proposed model along with the existing knowledge would enhance our ability to predict zinc binding sites in proteins, which is today of growing importance given the predicted enormity of the zinc proteome.

  7. Eurycomanone induce apoptosis in HepG2 cells via up-regulation of p53

    PubMed Central

    Zakaria, Yusmazura; Rahmat, Asmah; Pihie, Azimahtol Hawariah Lope; Abdullah, Noor Rain; Houghton, Peter J

    2009-01-01

    Background Eurycomanone is a cytotoxic compound found in Eurycoma longifolia Jack. Previous studies had noted the cytotoxic effect against various cancer cell lines. The aim of this study is to investigate the cytotoxicity against human hepato carcinoma cell in vitro and the mode of action. The cytotoxicity of eurycomanone was evaluated using MTT assay and the mode of cell death was detected by Hoechst 33258 nuclear staining and flow cytometry with Annexin-V/propidium iodide double staining. The protein expression Bax, Bcl-2, p53 and cytochrome C were studied by flow cytometry using a spesific antibody conjugated fluorescent dye to confirm the up-regulation of p53 and Bax in cancer cells. Results The findings suggested that eurycomanone was cytotoxic on cancerous liver cell, HepG2 and less toxic on normal cells Chang's liver and WLR-68. Furthermore, various methods proved that apoptosis was the mode of death in eurycomanone-treated HepG2 cells. The characteristics of apoptosis including chromatin condensation, DNA fragmentation and apoptotic bodies were found following eurycomanone treatment. This study also found that apoptotic process triggered by eurycomanone involved the up-regulation of p53 tumor suppressor protein. The up-regulation of p53 was followed by the increasing of pro-apoptotic Bax and decreasing of anti-apoptotic Bcl-2. The increased of cytochrome C levels in cytosol also results in induction of apoptosis. Conclusion The data suggest that eurycomanone was cytotoxic on HepG2 cells by inducing apoptosis through the up-regulation of p53 and Bax, and down-regulation of Bcl-2. PMID:19508737

  8. High Glucose Up-regulates ADAM17 through HIF-1α in Mesangial Cells.

    PubMed

    Li, Renzhong; Uttarwar, Lalita; Gao, Bo; Charbonneau, Martine; Shi, Yixuan; Chan, John S D; Dubois, Claire M; Krepinsky, Joan C

    2015-08-28

    We previously showed that ADAM17 mediates high glucose-induced matrix production by kidney mesangial cells. ADAM17 expression is increased in diabetic kidneys, suggesting that its up-regulation may augment high glucose profibrotic responses. We thus studied the effects of high glucose on ADAM17 gene regulation. Primary rat mesangial cells were treated with high glucose (30 mm) or mannitol as osmotic control. High glucose dose-dependently increased ADAM17 promoter activity, transcript, and protein levels. This correlated with augmented ADAM17 activity after 24 h versus 1 h of high glucose. We tested involvement of transcription factors shown in other settings to regulate ADAM17 transcription. Promoter activation was not affected by NF-κB or Sp1 inhibitors, but was blocked by hypoxia-inducible factor-1α (HIF-1α) inhibition or down-regulation. This also prevented ADAM17 transcript and protein increases. HIF-1α activation by high glucose was shown by its increased nuclear translocation and activation of the HIF-responsive hypoxia-response element (HRE)-luciferase reporter construct. Assessment of ADAM17 promoter deletion constructs coupled with mutation analysis and ChIP studies identified HIF-1α binding to its consensus element at -607 as critical for the high glucose response. Finally, inhibitors of epidermal growth factor receptor (EGFR) and downstream PI3K/Akt, or ADAM17 itself, prevented high glucose-induced HIF-1α activation and ADAM17 up-regulation. Thus, high glucose induces ADAM17 transcriptional up-regulation in mesangial cells, which is associated with augmentation of its activity. This is mediated by HIF-1α and requires EGFR/ADAM17 signaling, demonstrating the potentiation by ADAM17 of its own up-regulation. ADAM17 inhibition thus provides a potential novel therapeutic strategy for the treatment of diabetic nephropathy.

  9. Coordinated and Distinct Functions of Velvet Proteins in Fusarium verticillioides

    PubMed Central

    Lan, Nan; Zhang, Hanxing; Hu, Chengcheng; Wang, Wenzhao; Calvo, Ana M.; Harris, Steven D.; Chen, She

    2014-01-01

    Velvet-domain-containing proteins are broadly distributed within the fungal kingdom. In the corn pathogen Fusarium verticillioides, previous studies showed that the velvet protein F. verticillioides VE1 (FvVE1) is critical for morphological development, colony hydrophobicity, toxin production, and pathogenicity. In this study, tandem affinity purification of FvVE1 revealed that FvVE1 can form a complex with the velvet proteins F. verticillioides VelB (FvVelB) and FvVelC. Phenotypic characterization of gene knockout mutants showed that, as in the case of FvVE1, FvVelB regulated conidial size, hyphal hydrophobicity, fumonisin production, and oxidant resistance, while FvVelC was dispensable for these biological processes. Comparative transcriptional analysis of eight genes involved in the ROS (reactive oxygen species) removal system revealed that both FvVE1 and FvVelB positively regulated the transcription of a catalase-encoding gene, F. verticillioides CAT2 (FvCAT2). Deletion of FvCAT2 resulted in reduced oxidant resistance, providing further explanation of the regulation of oxidant resistance by velvet proteins in the fungal kingdom. PMID:24792348

  10. Protein-responsive assemblies from catechol-metal ion supramolecular coordination.

    PubMed

    Yuan, C; Chen, J; Yu, S; Chang, Y; Mao, J; Xu, Y; Luo, W; Zeng, B; Dai, L

    2015-03-21

    Supramolecular self-assembly driven by catechol-metal ion coordination has gained great success in the fabrication of functional materials including adhesives, capsules, coatings and hydrogels. However, this route has encountered a great challenge in the construction of nanoarchitectures in the absence of removable templates, because of the uncontrollable crosslinking of catechol-metal ion coordination. Herein, we show that a supramolecular approach, combining both catechol-metal ion coordination and polymer self-assembly together, can organize polymers into hybrid nanoassemblies ranging from solid particles, homogeneous vesicles to Janus vesicles. Without the introduction of a specific binding ligand or complicated molecular design, these assemblies can totally disassemble in response to proteins. UV/vis absorption, fluorescence quenching and recovery investigations have confirmed that proteins can seize metal ions from the hybrid nanoassemblies, thus causing the degradation of catechol-metal ion coordination networks.

  11. Hyaluronan up-regulation is linked to renal dysfunction and hearing loss induced by silver nanoparticles.

    PubMed

    Feng, Hao; Pyykkö, Ilmari; Zou, Jing

    2015-10-01

    Increased application of silver nanoparticles (AgNPs) has raised concerns on their potential adverse effects on human health. However, the precise toxicological mechanisms are not known in detail. The current study hypothesized that AgNPs induced glycosaminoglycan accumulation in the basement membrane that associated with the up-regulation of its component hyaluronic acid, known as a hydrophilic molecule of binding and retaining water, and caused toxicities in the kidney and cochlea. Rats administered AgNPs through either intravenous or intratympanic injection were observed at different time points after exposure. The concentrations of creatinine and urea in the serum were elevated remarkably, and proteins leaked into the urine were increased. A significant hearing loss over a broad range of frequencies was indicated. AgNP exposure induced glycosaminoglycan accumulation and hyaluronic acid up-regulation in the basement membrane. Abundant apoptotic cell death was demonstrated in the AgNP-exposed organs. Our results suggested that glycosaminoglycan accumulation associated with the up-regulation of hyaluronic acid was involved in the toxicities of kidney and cochlea caused by AgNPs.

  12. Up-regulation of miR-98 and unraveling regulatory mechanisms in gestational diabetes mellitus

    PubMed Central

    Cao, Jing-Li; Zhang, Lu; Li, Jian; Tian, Shi; Lv, Xiao-Dan; Wang, Xue-Qin; Su, Xing; Li, Ying; Hu, Yi; Ma, Xu; Xia, Hong-Fei

    2016-01-01

    MiR-98 expression was up-regulated in kidney in response to early diabetic nephropathy in mouse and down-regulated in muscle in type 2 diabetes in human. However, the expression prolife and functional role of miR-98 in human gestational diabetes mellitus (GDM) remained unclear. Here, we investigated its expression and function in placental tissues from GDM patients and the possible molecular mechanisms. The results showed that miR-98 was up-regulated in placentas from GDM patients compared with normal placentas. MiR-98 over-expression increased global DNA methylational level and miR-98 knockdown reduced global DNA methylational level. Further investigation revealed that miR-98 could inhibit Mecp2 expression by binding the 3′-untranslated region (UTR) of methyl CpG binding protein 2 (Mecp2), and then led to the expression dysregulation of canonical transient receptor potential 3 (Trpc3), a glucose uptake related gene. More importantly, in vivo analysis found that the expression level of Mecp2 and Trpc3 in placental tissues from GDM patients, relative to the increase of miR-98, was diminished, especially for GDM patients over the age of 35 years. Collectively, up-regulation of miR-98 in the placental tissues of human GDM is linked to the global DNA methylation via targeting Mecp2, which may imply a novel regulatory mechanism in GDM. PMID:27573367

  13. Mg2+ coordinating dynamics in Mg:ATP fueled motor proteins

    NASA Astrophysics Data System (ADS)

    Bojovschi, A.; Liu, Ming S.; Sadus, Richard J.

    2014-03-01

    The coordination of Mg2+ with the triphosphate group of adenosine triphosphate (ATP) in motor proteins is investigated using data mining and molecular dynamics. The possible coordination structures available from crystal data for actin, myosin, RNA polymerase, DNA polymerase, DNA helicase, and F1-ATPase are verified and investigated further by molecular dynamics. Coordination states are evaluated using structural analysis and quantified by radial distribution functions, coordination numbers, and pair interaction energy calculations. The results reveal a diverse range of both transitory and stable coordination arrangements between Mg2+ and ATP. The two most stable coordinating states occur when Mg2+ coordinates two or three oxygens from the triphosphate group of ATP. Evidence for five-site coordination is also reported involving water in addition to the triphosphate group. The stable states correspond to a pair interaction energy of either ˜-2750 kJ/mol or -3500 kJ/mol. The role of water molecules in the hydration shell surrounding Mg2+ is also reported.

  14. Nitric oxide up-regulates endothelial expression of angiotensin II type 2 receptors.

    PubMed

    Dao, Vu Thao-Vi; Medini, Sawsan; Bisha, Marion; Balz, Vera; Suvorava, Tatsiana; Bas, Murat; Kojda, Georg

    2016-07-15

    Increasing vascular NO levels following up-regulation of endothelial nitric oxide synthase (eNOS) is considered beneficial in cardiovascular disease. Whether such beneficial effects exerted by increased NO-levels include the vascular renin-angiotensin system remains elucidated. Exposure of endothelial cells originated from porcine aorta, mouse brain and human umbilical veins to different NO-donors showed that expression of the angiotensin-II-type-2-receptor (AT2) mRNA and protein is up-regulated by activation of soluble guanylyl cyclase, protein kinase G and p38 mitogen-activated protein kinase without changing AT2 mRNA stability. In mice, endothelial-specific overexpression of eNOS stimulated, while chronic treatment with the NOS-blocker l-nitroarginine inhibited AT2 expression. The NO-induced AT2 up-regulation was associated with a profound inhibition of angiotensin-converting enzyme (ACE)-activity. In endothelial cells this reduction of ACE-activity was reversed by either the AT2 antagonist PD 123119 or by inhibition of transcription with actinomycin D. Furthermore, in C57Bl/6 mice an acute i.v. bolus of l-nitroarginine did not change AT2-expression and ACE-activity suggesting that inhibition of ACE-activity by endogenous NO is crucially dependent on AT2 protein level. Likewise, three weeks of either voluntary or forced exercise training increased AT2 expression and reduced ACE-activity in C57Bl/6 but not in mice lacking eNOS suggesting significance of this signaling interaction for vascular physiology. Finally, aortic AT2 expression is about 5 times greater in female as compared to male C57Bl/6 and at the same time aortic ACE activity is reduced in females by more than 50%. Together these findings imply that endothelial NO regulates AT2 expression and that AT2 may regulate ACE-activity. PMID:27235748

  15. Peptide tag/probe pairs based on the coordination chemistry for protein labeling.

    PubMed

    Uchinomiya, Shohei; Ojida, Akio; Hamachi, Itaru

    2014-02-17

    Protein-labeling methods serve as essential tools for analyzing functions of proteins of interest under complicated biological conditions such as in live cells. These labeling methods are useful not only to fluorescently visualize proteins of interest in biological systems but also to conduct protein and cell analyses by harnessing the unique functions of molecular probes. Among the various labeling methods available, an appropriate binding pair consisting of a short peptide and a de novo designed small molecular probe has attracted attention because of its wide utility and versatility. Interestingly, most peptide tag/probe pairs exploit metal-ligand coordination interactions as the main binding force responsible for their association. Herein, we provide an overview of the recent progress of these coordination-chemistry-based protein-labeling methods and their applications for fluorescence imaging and functional analysis of cellular proteins, while highlighting our originally developed labeling methods. These successful examples clearly exemplify the utility and versatility of metal coordination chemistry in protein functional analysis.

  16. Maternal obesity is associated with ovarian inflammation and up-regulation of early growth response factor 1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity impairs reproductive functions through multiple mechanisms, possibly through disruption of ovarian function. We hypothesized that increased adiposity will lead to a pro-inflammatory gene signature and up-regulation of Egr-1 protein in ovaries from obese (OB, n=7) compared to lean (LN, n=10) ...

  17. Celecoxib Up Regulates the Expression of Drug Efflux Transporter ABCG2 in Breast Cancer Cell Lines

    PubMed Central

    Kalalinia, Fatemeh; Elahian, Fatemeh; Mosaffa, Fatemeh; Behravan, Javad

    2014-01-01

    Elevated expression of the drug efflux transporter ABCG2 seems to correlate with multidrug resistance of cancer cells. Specific COX-2 inhibitor celecoxib has been shown to enhance the sensitivity of cancer cells to anticancer drugs. To clarify whether ABCG2 inhibition is involved in the sensitizing effect of celecoxib, we investigated whether the expression of ABCG2 in breast cancer cell lines, could be modulated by celecoxib. The expression of the multidrug resistant gene (ABCG2) at mRNA and protein level was detected by real-time quantitative reverse transcription-polymerase chain reaction and flow cytometry analysis, respectively. Among three human breast cancer cell lines ABCG2 and COX-2 were highly expressed in MCF7-MX and MDA-MB-231 cells, respectively. The COX-2 inhibitor celecoxib up-regulated the expression of ABCG2 mRNA in MCF-7 and MCF7-MX cells, which was accompanied by increased ABCG2 protein expression. While celecoxib was able to block the 12-O-tetradecanoylphorbol-13-acetate (TPA)-mediated increase in COX-2 expression in MDA-MB-231 cells, it increased the expression of ABCG2 up to 4.27 times to the control level at mRNA level and with less intensity at protein level. Our findings provide evidence that celecoxib up-regulates ABCG2 expression in human breast cancer cells and proposed that ABCG2 is not involved in chemosensitizing effects of celecoxib. PMID:25587329

  18. Dietary iron-deficiency up-regulates hephaestin mRNA level in small intestine of rats.

    PubMed

    Sakakibara, Shoji; Aoyama, Yoritaka

    2002-05-17

    Hephaestin is a protein, recently found from the study of sla (sex-linked anemia) mouse. Hephaestin is suggested to transport iron from intestinal enterocytes into the circulation. Iron is essential for living and for humans to maintain a constant total iron concentration in whole body. In this study, it was found that dietary iron-deficiency up-regulated hephaestin mRNA level in the proximal small intestine of rats. Therefore, it is suggested that in dietary iron-deficiency, hephaestin gene expression in proximal small intestine is up-regulated to absorb more iron from diet.

  19. Rck1 up-regulates pseudohyphal growth by activating the Ras2 and MAP kinase pathways independently in Saccharomyces cerevisiae.

    PubMed

    Chang, Miwha; Kang, Chang-Min; Park, Yong-Sung; Yun, Cheol-Won

    2014-02-21

    Previously, we reported that Rck1 regulates Hog1 and Slt2 activities and affects MAP kinase activity in Saccharomyces cerevisiae. Recently, we found that Rck1 up-regulates phospho-Kss1 and phospho-Fus3. Kss1 has been known as a component in the pseudohyphal growth pathway, and we attempted to identify the function of Rck1 in pseudohyphal growth. Rck1 up-regulated Ras2 at the protein level, not the transcriptional level. Additionally, FLO11 transcription was up-regulated by RCK1 over-expression. RCK1 expression was up-regulated during growth on SLAD+1% butanol medium. On nitrogen starvation agar plates, RCK1 over-expression induced pseudohyphal growth of colonies, and cells over-expressing RCK1 showed a filamentous morphology when grown in SLAD medium. Furthermore, 1-butanol greatly induced filamentous growth when RCK1 was over-expressed. Moreover, invasive growth was activated in haploid cells when RCK1 was over-expressed. The growth defect of cells observed on 1-butanol medium was recovered when RCK1 was over-expressed. Interestingly, Ras2 and phospho-Kss1 were up-regulated by Rck1 independently. Together, these results suggest that Rck1 promotes pseudohyphal growth by activating Ras2 and Kss1 via independent pathways in S. cerevisiae. PMID:24491552

  20. GATA-4 promotes myocardial transdifferentiation of mesenchymal stromal cells via up-regulating IGFBP-4

    PubMed Central

    LI, HONGXIA; ZUO, SHI; PASHA, ZEESHAN; YU, BIN; HE, ZHISONG; WANG, YIGANG; YANG, XIANGJUN; ASHRAF, MUHAMMAD; XU, MEIFENG

    2012-01-01

    Background aims GATA-4 is a cardiac transcription factor and plays an important role in cell lineage differentiation during development. We investigated whether overexpression of GATA-4 increases adult mesenchymal stromal cell (MSC) transdifferentiation into a cardiac phenotype in vitro. Methods MSC were harvested from rat bone marrow (BM) and transduced with GATA-4 (MSCGATA-4) using a murine stem cell virus (pMSCV) retroviral expression system. Gene expression in MSCGATA-4 was analyzed using quantitative reverse transcription–polymerase chain reaction (RT-PCR) and Western blotting. Native cardiomyocytes (CM) were isolated from ventricles of neonatal rats. Myocardial transdifferentiation of MSC was determined by immunostaining and electrophysiologic recording. The transdifferentiation rate was calculated directly from flow cytometery. Results The expression of cardiac genes, including brain natriuretic peptide (BNP), Islet-1 and α-sarcomeric actinin (α-SA), was up-regulated in MSCGATA-4 compared with control cells that were transfected with Green Fluorescent Protein (GFP) only (MSCNull). At the same time, insulin-like growth factor-binding protein (IGFBP)-4 was significantly up-regulated in MSCGATA-4. A synchronous beating of MSC with native CM was detected and an action potential was recorded. Some GFP + cells were positive for α-SA staining after MSC were co-cultured with native CM for 7 days. The transdifferentiation rate was significantly higher in MSCGATA-4. Functional studies indicated that the differentiation potential of MSCGATA-4 was decreased by knockdown of IGFBP-4. Conclusions Overexpression of GATA-4 significantly increases MSC differentiation into a myocardial phenotype, which might be associated with the up-regulation of IGFBP-4. PMID:21846294

  1. Erbb2 up-regulation of ADAM12 expression accelerates skin cancer progression.

    PubMed

    Rao, Velidi H; Vogel, Kristen; Yanagida, Jodi K; Marwaha, Nitin; Kandel, Amrit; Trempus, Carol; Repertinger, Susan K; Hansen, Laura A

    2015-10-01

    Solar ultraviolet (UV) radiation can cause severe damage to the skin and is the primary cause of most skin cancer. UV radiation causes DNA damage leading to mutations and also activates the Erbb2/HER2 receptor through indirect mechanisms involving reactive oxygen species. We hypothesized that Erbb2 activation accelerates the malignant progression of UV-induced skin cancer. Following the induction of benign squamous papillomas by UV exposure of v-ras(Ha) transgenic Tg.AC mice, mice were treated topically with the Erbb2 inhibitor AG825 and tumor progression monitored. AG825 treatment reduced tumor volume, increased tumor regression, and delayed the development of malignant squamous cell carcinoma (SCC). Progression to malignancy was associated with increased Erbb2 and ADAM12 (A Disintegin And Metalloproteinase 12) transcripts and protein, while inhibition of Erbb2 blocked the increase in ADAM12 message upon malignant progression. Similarly, human SCC and SCC cell lines had increased ADAM12 protein and transcripts when compared to normal controls. To determine whether Erbb2 up-regulation of ADAM12 contributed to malignant progression of skin cancer, Erbb2 expression was modulated in cultured SCC cells using forced over-expression or siRNA targeting, demonstrating up-regulation of ADAM12 by Erbb2. Furthermore, ADAM12 transfection or siRNA targeting revealed that ADAM12 increased both the migration and invasion of cutaneous SCC cells. Collectively, these results suggest Erbb2 up-regulation of ADAM12 as a novel mechanism contributing to the malignant progression of UV-induced skin cancer. Inhibition of Erbb2/HER2 reduced tumor burden, increased tumor regression, and delayed the progression of benign skin tumors to malignant SCC in UV-exposed mice. Inhibition of Erbb2 suppressed the increase in metalloproteinase ADAM12 expression in skin tumors, which in turn increased migration and tumor cell invasiveness.

  2. Transforming growth factor-β1 up-regulates connexin43 expression in human granulosa cells

    PubMed Central

    Chen, Yu-Ching; Chang, Hsun-Ming; Cheng, Jung-Chien; Tsai, Horng-Der; Wu, Cheng-Hsuan; Leung, Peter C.K.

    2015-01-01

    STUDY QUESTION Does transforming growth factor-β1 (TGF-β1) up-regulate connexin43 (Cx43) to promote cell–cell communication in human granulosa cells? SUMMARY ANSWER TGF-β1 up-regulates Cx43 and increases gap junction intercellular communication activities (GJIC) in human granulosa cells, and this effect occurs via the activin receptor-like kinase (ALK)5-mediated Sma- and Mad-related protein (SMAD)2/3-SMAD4-dependent pathway. WHAT IS KNOWN ALREADY TGF-β1 and its receptors are expressed in human granulosa cells, and follicular fluid contains TGF-β1 protein. In human granulosa cells, Cx43 gap junctions play an important role in the development of follicles and oocytes. STUDY DESIGN, SIZE, DURATION This is an experimental study which was performed over a 1-year period. PARTICIPANTS/MATERIALS, SETTING, METHODS Immortalized human granulosa cells (SVOG cells) and primary human granulosa-lutein cells obtained from women undergoing IVF in an academic research center were used as the study models. Cx43 mRNA and protein expression levels were examined after exposure of SVOG cells to recombinant human TGF-β1. An activin/TGF-β type I receptor inhibitor, SB431542, and small interfering RNAs targeting ALK4, ALK5, SMAD2, SMAD3 and SMAD4 were used to verify the specificity of the effects and to investigate the molecular mechanisms. Real-time-quantitative PCR and western blot analysis were used to detect the specific mRNA and protein levels, respectively. GJIC between SVOG cells were evaluated using a scrape loading and dye transfer assay. Results were analyzed by one-way analysis of variance. MAIN RESULTS AND THE ROLE OF CHANCE TGF-β1 treatment increased phosphorylation of SMAD2/3 (P < 0.0001) and up-regulated Cx43 mRNA and protein levels (P < 0.001) in SVOG cells and these stimulatory effects were abolished by the TGF-β type I receptor inhibitor SB431542. In addition, the up-regulatory effect of TGF-β1 on Cx43 expression (mRNA and protein) was confirmed in primary

  3. Utrophin Up-Regulation by an Artificial Transcription Factor in Transgenic Mice

    PubMed Central

    Mattei, Elisabetta; Corbi, Nicoletta; Di Certo, Maria Grazia; Strimpakos, Georgios; Severini, Cinzia; Onori, Annalisa; Desantis, Agata; Libri, Valentina; Buontempo, Serena; Floridi, Aristide; Fanciulli, Maurizio; Baban, Dilair; Davies, Kay E.; Passananti, Claudio

    2007-01-01

    Duchenne Muscular Dystrophy (DMD) is a severe muscle degenerative disease, due to absence of dystrophin. There is currently no effective treatment for DMD. Our aim is to up-regulate the expression level of the dystrophin related gene utrophin in DMD, complementing in this way the lack of dystrophin functions. To this end we designed and engineered several synthetic zinc finger based transcription factors. In particular, we have previously shown that the artificial three zinc finger protein named Jazz, fused with the appropriate effector domain, is able to drive the transcription of a test gene from the utrophin promoter “A”. Here we report on the characterization of Vp16-Jazz-transgenic mice that specifically over-express the utrophin gene at the muscular level. A Chromatin Immunoprecipitation assay (ChIP) demonstrated the effective access/binding of the Jazz protein to active chromatin in mouse muscle and Vp16-Jazz was shown to be able to up-regulate endogenous utrophin gene expression by immunohistochemistry, western blot analyses and real-time PCR. To our knowledge, this is the first example of a transgenic mouse expressing an artificial gene coding for a zinc finger based transcription factor. The achievement of Vp16-Jazz transgenic mice validates the strategy of transcriptional targeting of endogenous genes and could represent an exclusive animal model for use in drug discovery and therapeutics. PMID:17712422

  4. Utrophin up-regulation by an artificial transcription factor in transgenic mice.

    PubMed

    Mattei, Elisabetta; Corbi, Nicoletta; Di Certo, Maria Grazia; Strimpakos, Georgios; Severini, Cinzia; Onori, Annalisa; Desantis, Agata; Libri, Valentina; Buontempo, Serena; Floridi, Aristide; Fanciulli, Maurizio; Baban, Dilair; Davies, Kay E; Passananti, Claudio

    2007-08-22

    Duchenne Muscular Dystrophy (DMD) is a severe muscle degenerative disease, due to absence of dystrophin. There is currently no effective treatment for DMD. Our aim is to up-regulate the expression level of the dystrophin related gene utrophin in DMD, complementing in this way the lack of dystrophin functions. To this end we designed and engineered several synthetic zinc finger based transcription factors. In particular, we have previously shown that the artificial three zinc finger protein named Jazz, fused with the appropriate effector domain, is able to drive the transcription of a test gene from the utrophin promoter "A". Here we report on the characterization of Vp16-Jazz-transgenic mice that specifically over-express the utrophin gene at the muscular level. A Chromatin Immunoprecipitation assay (ChIP) demonstrated the effective access/binding of the Jazz protein to active chromatin in mouse muscle and Vp16-Jazz was shown to be able to up-regulate endogenous utrophin gene expression by immunohistochemistry, western blot analyses and real-time PCR. To our knowledge, this is the first example of a transgenic mouse expressing an artificial gene coding for a zinc finger based transcription factor. The achievement of Vp16-Jazz transgenic mice validates the strategy of transcriptional targeting of endogenous genes and could represent an exclusive animal model for use in drug discovery and therapeutics.

  5. HBx sensitizes hepatocellular carcinoma cells to lapatinib by up-regulating ErbB3

    PubMed Central

    Yen, Chia-Jui; Chen, Wen-Shu; Huang, Wei-Chien

    2016-01-01

    Poor prognosis of hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) involves HBV X protein (HBx)-induced tumor progression. HBx also contributes to chemo-resistance via inducing the expressions of anti-apoptosis and multiple drug resistance genes. However, the impact of HBx expression on the therapeutic efficacy of various receptor tyrosine kinase inhibitors remains unknown. In this study, our data showed that HBx overexpression did not alter the cellular sensitivity of HCC cell lines to sorafenib but unexpectedly enhanced the cell death induced by EGFR family inhibitors, including gefitinib, erlotinib, and lapatinib due to ErbB3 up-regulation. Mechanistically, HBx transcriptionally up-regulates ErbB3 expression in a NF-κB dependent manner. In addition, HBx also physically interacts with ErbB2 and ErbB3 proteins and enhances the formation of ErbB2/ErbB3 heterodimeric complex. The cell viability of HBx-overexpressing cells was decreased by silencing ErbB3 expression, further revealing the pivotal role of ErbB3 in HBx-mediated cell survival. Our data suggest that HBx shifts the oncogenic addiction of HCC cells to ErbB2/ErbB3 signaling pathway via inducing ErbB3 expression and thereby enhances their sensitivity to EGFR/ErbB2 inhibitors. PMID:26595522

  6. Midazolam inhibits the hypoxia-induced up-regulation of erythropoietin in the central nervous system.

    PubMed

    Matsuyama, Tomonori; Tanaka, Tomoharu; Tatsumi, Kenichiro; Daijo, Hiroki; Kai, Shinichi; Harada, Hiroshi; Fukuda, Kazuhiko

    2015-08-15

    Erythropoietin (EPO), a regulator of red blood cell production, is endogenously expressed in the central nervous system. It is mainly produced by astrocytes under hypoxic conditions and has proven to have neuroprotective and neurotrophic effects. In the present study, we investigated the effect of midazolam on EPO expression in primary cultured astrocytes and the mouse brain. Midazolam was administered to 6-week-old BALB/c male mice under hypoxic conditions and pregnant C57BL/6N mice under normoxic conditions. Primary cultured astrocytes were also treated with midazolam under hypoxic conditions. The expression of EPO mRNA in mice brains and cultured astrocytes was studied. In addition, the expression of hypoxia-inducible factor (HIF), known as the main regulator of EPO, was evaluated. Midazolam significantly reduced the hypoxia-induced up-regulation of EPO in BALB/c mice brains and primary cultured astrocytes and suppressed EPO expression in the fetal brain. Midazolam did not affect the total amount of HIF proteins but significantly inhibited the nuclear expression of HIF-1α and HIF-2α proteins. These results demonstrated the suppressive effects of midazolam on the hypoxia-induced up-regulation of EPO both in vivo and in vitro. PMID:26001375

  7. Serum withdrawal up-regulates human SIRT1 gene expression in a p53-dependent manner.

    PubMed

    Shang, Linshan; Zhou, Haibin; Xia, Yu; Wang, Hui; Gao, Guimin; Chen, Bingxi; Liu, Qiji; Shao, Changshun; Gong, Yaoqin

    2009-10-01

    SIRT1, a nicotinamide adenine dinucleotide (NAD(+))-dependent histone/protein deacetylase, has been extensively studied recently for its critical role in the regulation of physiology, calorie restriction and aging. Studies on laboratory mice showed that expression of SIRT1 can be induced by starvation in a p53-dependent manner and requires the p53-binding sites present in the Sirt1 promoter. However, it remains to be determined whether these findings based on rodents apply to human beings. In this paper, we characterized a putative p53-binding element in the human SIRT1 promoter that might be required for the up-regulation of SIRT1 in response to nutritional stress. The p53-binding site in the promoter of human SIRT1 is more deviant from the consensus sequence than the corresponding sequence in the mouse Sirt1. There is a C to A change at the second half site in human SIRT1, thus disrupting the core-binding element CWWG in the canonical RRRCWWGYYY. To test whether such sequence change would affect its binding with p53 and the SIRT1 expression under stress, we studied various human cell lines with different p53 status and cells with ectopic expression of functionally distinct p53. We found that serum withdrawal also up-regulates human SIRT1 gene expression in a p53-dependent manner and that the p53-binding element in SIRT1 is required for the up-regulation. Thus, the mechanism responsible for the regulation of SIRT1 expression by p53 is conserved between mice and human beings.

  8. Up-regulation of gamma-glutamyl transpeptidase (GGT) activity in growth perturbed C6 astrocytes.

    PubMed

    Mares, V; Malík, R; Lisá, V; Sedo, A

    2005-05-20

    Activity of gamma-glutamyl transpeptidase (GGT) was studied in astrocyte-like C6 glial cells modulated in growth and maturation by different concentration of serum and dibutyryl cyclic AMP (Db-cAMP) supplement in culture medium. After reduction of serum concentration from 10% to 0.1%, the number of GGT positive cells determined histochemically increased 3.1 times and the GGT activity/mg protein in whole cell lysates was 5.1 times higher. In cultures with 0.1% serum + Db-cAMP, the histochemically and biochemically assayed GGT activity exceeded 5.1 and 7.9 times the values measured in control 10% serum cultures, respectively. The up-regulation of GGT was accompanied by an inhibition of proliferation, enhanced differentiation and hypertrophy of cells. In addition, the process of metabolic perturbation and/or cellular stress was revealed in these cultures by the (i) growth-support release followed by shrinkage and death of a small number of cells and (ii) higher oxidation of 2'7'dichlorofluorescein diacetate to its fluorescent form in the adherent/viable cells. The observed up-regulation of GGT is considered to primarily reflect increased metabolism of glutathione and/or the maintenance of the redox potential in cells stressed by sub-optimal concentration of serum and Db-cAMP supplement. The concomitant cellular hypertrophy and differentiation and their relationship to increased activity of GGT await further investigation. The study suggests that up-regulation of GGT can contribute to adaptation of astrocytic cells to metabolic and/or oxidative perturbances occurring under various pathological conditions, including radiation- and drug-induced toxicity. PMID:15893589

  9. Up-regulation of divalent metal transporter 1 in 6-hydroxydopamine intoxication is IRE/IRP dependent.

    PubMed

    Jiang, Hong; Song, Ning; Xu, Huamin; Zhang, Shuzhen; Wang, Jun; Xie, Junxia

    2010-03-01

    Iron plays a key role in Parkinson's disease (PD). Increased iron content of the substantia nigra (SN) has been found in PD patients, and divalent metal transporter 1 (DMT1) has been shown to be up-regulated in the SN of both MPTP-induced PD models and PD patients. However, the mechanisms underlying DMT1 up-regulation are largely unknown. In the present study, we observed that in the SN of 6-hydroxydopamine (6-OHDA)-induced PD rats, DMT1 with the iron responsive element (IRE, DMT1+IRE), but not DMT1 without IRE (DMT1-IRE), was up-regulated, suggesting that increased DMT1+IRE expression might account for nigral iron accumulation in PD rats. This possibility was further assessed in an in vitro study using 6-OHDA-treated and DMT1+IRE-over-expressing MES23.5 cells. In 6-OHDA-treated MES23.5 cells, increased iron regulatory protein (IRP) 1 and IRP2 expression was observed, while silencing of IRPs dramatically diminished 6-OHDA-induced DMT1+IRE up-regulation. Pretreatment with N-acetyl-L-cysteine fully suppressed IRPs up-regulation by inhibition of 6-OHDA-induced oxidative stress. Increased DMT1+IRE expression resulted in increased iron influx by MES23.5 cells. Our data provide direct evidence that DMT1+IRE up-regulation can account for IRE/IRP-dependent 6-OHDA-induced iron accumulation initiated by 6-OHDA-induced intracellular oxidative stress and that increased levels of intracellular iron result in aggravated oxidative stress. The results of this study provide novel evidence supporting the use of anti-oxidants in the treatment of PD, with the goal of inhibiting iron accumulation by regulation of DMT1 expression. PMID:20125122

  10. Mycoplasma arthritidis mitogen up-regulates human NK cell activity.

    PubMed Central

    D'Orazio, J A; Cole, B C; Stein-Streilein, J

    1996-01-01

    While the effects of superantigens on T lymphocytes are well characterized, how superantigens interact with other immune cells is less clear. This report examines the effects of Mycoplasma arthritidis mitogen (MAM) on human natural killer (NK) cell activity. Incubation of peripheral blood mononuclear cells (PBMC) with MAM for 16 to 20 h augmented NK cytotoxicity (against K562) in a dose-dependent manner (P < or = 0.05). Superantigen-dependent cellular cytotoxicity, an activity of superantigen-activated cytotoxic T cells, was not involved in lysis of K562 cells because the erythroleukemic tumor target cells expressed no class II major histocompatibility complex by fluorescence-activated cell sorter analysis. Kinetic experiments showed that the largest increase in NK activity induced by MAM occurred within 48 h. Incubation with MAM caused a portion of NK cells to become adherent to tissue culture flasks, a quality associated with activation, and augmented NK activity was found in both adherent and nonadherent subpopulations. Experiments using cytokine-specific neutralizing antibodies showed that interleukin-2 contributed to enhancement of the NK activity observed in superantigen-stimulated PBMC. Interestingly, MAM was able to augment NK lysis of highly purified NK (CD56+) cells in the absence of other immune cells in 9 of 12 blood specimens, with the augmented lytic activity ranging from 110 to 170% of unstimulated NK activity. In summary, data presented in this report show for the first time that MAM affects human NK cells directly by increasing their lytic capacity and indirectly in PBMC as a consequence of cytokines produced by T cells. Results of this work suggest that, in vivo, one consequence of interaction with superantigen-secreting microorganisms may be up-regulation of NK lytic activity. These findings may have clinical application as a means of generating augmented NK effector cells useful in the immunotherapy of parasitic infections or neoplasms. PMID

  11. A novel transcript is up-regulated by fasting in the hypothalamus and enhances insulin signalling.

    PubMed

    Chai, B; Li, J-Y; Fritze, D; Zhang, W; Xia, Z; Mulholland, M W

    2013-03-01

    A transcript of unknown function, regulated by fasting and feeding, was identified by microarray analysis. The transcript is up-regulated in the fasting state. An 1168-bp cDNA was cloned from rat hypothalamus and sequenced. This sequence is consistent with adipogenesis down-regulating transcript 3 (AGD3) (also known as human OCC-1) mRNA. A protein sequence identical to AGD3 was determined by mass spectrometry. In the rat brain, AGD3 mRNA is distributed in the arcuate nucleus, ventromedial hypothalamus, amygdaloid nuclei, hippocampus, and somatic cortex. Double in situ hybridisation showed that AGD3 mRNA is co-localised with pro-opiomelanocortin and neuropeptide Y in arcuate nucleus neurones. AGD3 binds with insulin receptor substrate 4 and increases insulin-stimulated phospho-Akt and regulates AMP-activated protein kinase and mammalian target of rapamycin downstream target S6 kinase phosphorylation.

  12. Building proteins from C alpha coordinates using the dihedral probability grid Monte Carlo method.

    PubMed Central

    Mathiowetz, A. M.; Goddard, W. A.

    1995-01-01

    Dihedral probability grid Monte Carlo (DPG-MC) is a general-purpose method of conformational sampling that can be applied to many problems in peptide and protein modeling. Here we present the DPG-MC method and apply it to predicting complete protein structures from C alpha coordinates. This is useful in such endeavors as homology modeling, protein structure prediction from lattice simulations, or fitting protein structures to X-ray crystallographic data. It also serves as an example of how DPG-MC can be applied to systems with geometric constraints. The conformational propensities for individual residues are used to guide conformational searches as the protein is built from the amino-terminus to the carboxyl-terminus. Results for a number of proteins show that both the backbone and side chain can be accurately modeled using DPG-MC. Backbone atoms are generally predicted with RMS errors of about 0.5 A (compared to X-ray crystal structure coordinates) and all atoms are predicted to an RMS error of 1.7 A or better. PMID:7549885

  13. φXANES: In vivo imaging of metal-protein coordination environments

    NASA Astrophysics Data System (ADS)

    James, Simon A.; Hare, Dominic J.; Jenkins, Nicole L.; de Jonge, Martin D.; Bush, Ashley I.; McColl, Gawain

    2016-02-01

    We have developed an X-ray absorption near edge structure spectroscopy method using fluorescence detection for visualizing in vivo coordination environments of metals in biological specimens. This approach, which we term fluorescence imaging XANES (φXANES), allows us to spatially depict metal-protein associations in a native, hydrated state whilst avoiding intrinsic chemical damage from radiation. This method was validated using iron-challenged Caenorhabditis elegans to observe marked alterations in redox environment.

  14. φXANES: In vivo imaging of metal-protein coordination environments

    PubMed Central

    James, Simon A.; Hare, Dominic J.; Jenkins, Nicole L.; de Jonge, Martin D.; Bush, Ashley I.; McColl, Gawain

    2016-01-01

    We have developed an X-ray absorption near edge structure spectroscopy method using fluorescence detection for visualizing in vivo coordination environments of metals in biological specimens. This approach, which we term fluorescence imaging XANES (φXANES), allows us to spatially depict metal-protein associations in a native, hydrated state whilst avoiding intrinsic chemical damage from radiation. This method was validated using iron-challenged Caenorhabditis elegans to observe marked alterations in redox environment. PMID:26861174

  15. Tubular up-regulation of clusterin mRNA in murine lupus-like nephritis.

    PubMed Central

    Moll, S.; Menoud, P. A.; French, L.; Sappino, A. P.; Pastore, Y.; Schifferli, J. A.; Izui, S.

    1998-01-01

    Clusterin, a widely distributed glycoprotein, is detected in most tissues and in numerous physiological fluids. In the kidney, this protein is constitutively expressed in tubular epithelial cells, and its expression is enhanced following tubular injuries. In addition, clusterin has been detected in glomerular immune deposits of glomerulonephritis. The present study was designed to define the sites of clusterin mRNA accumulation in murine lupus-like nephritis in comparison with murine tubulopathies. In lupus-like nephritis, a significant increase of clusterin mRNA abundance was demonstrated. This up-regulation was localized exclusively in tubular epithelial cells exhibiting tubulointerstitial alterations, whereas no clusterin mRNA was detectable in diseased glomeruli, excluding an active synthesis of clusterin by glomerular cells. A similar tubular increase of clusterin mRNA abundance was observed in myeloma-like cast nephropathy induced by IgG3 monoclonal cryoglobulins and even in the absence of any detectable histological alterations in a model of septic shock induced by the injection of bacterial lipopolysaccharides. Our results suggest that tubular epithelial cells are the only sites of clusterin mRNA accumulation during the course of lupus-like nephritis and that the tubular up-regulation of clusterin gene expression may reflect the cellular response to various types of tubular injuries. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 7 PMID:9546356

  16. Up-regulation of NF45 correlates with Schwann cell proliferation after sciatic nerve crush.

    PubMed

    Wang, Youhua; Zhou, Shiran; Xu, Hua; Yan, Shixian; Xu, Dawei; Zhang, Yi

    2015-05-01

    Nuclear factor (NF)45 (also known as interleukin enhancer-binding factor (ILF)2), is a transcription factor that interacts with NF90 to regulate gene expression. It has long been implicated in the regulation of cell proliferation. However, the role of NF45 in the process of peripheral nervous system regeneration after injury remains poorly understood. Herein, we investigated the spatiotemporal expression of NF45 in a rat sciatic nerve crush model. We detected the up-regulated expression of NF45 in Schwann cell after sciatic nerve crush. What's more, the expression of the cell proliferation marker proliferating cell nuclear antigen (PCNA) exhibited a similar tendency with that of NF45. In cell cultures, we observed increased expression of NF45 during the process of TNF-α-induced Schwann cell proliferation, whereas the protein level of p21 was down-regulated. Interference of NF45 led to enhanced expression of p21 and also impaired proliferation of Schwan cells. Taken together, our data implicated that NF45 was up-regulated in the sciatic nerve after crush, which was associated with proliferation of Schwann cell.

  17. Up-regulated expression of Ran reveals its potential role to deltamethrin stress in Kc cells.

    PubMed

    Liu, Wei; Xu, Qin; Chi, Qingping; Hu, Junli; Li, Fengliang; Cheng, Luogen

    2016-05-25

    The GTP-binding nuclear protein Ran has mostly been reported to be an essential player in nuclear transport, chromosome alignment, microtubule dynamics, centrosome duplication, kinetochore attachment of microtubules, nuclear-envelope dynamics, and phagocytosis. However, until now, there has been no report showing the involvement of Ran in DM stress. In this paper, two-dimensional electrophoresis analysis showed that the expression level of Ran in Kc cells in response to DM was higher than that in the control group. In addition, quantitative analysis using real-time PCR revealed that the expression of Ran was obviously up-regulated at various concentrations of DM. Western blot analysis showed that Ran was up-regulated 2.27-fold over the control at 48h. Because we still could not pinpoint whether Ran was actually involved in DM stress reaction, to further verify the role of Ran in stress reaction, RNA interference and cell transfection were utilized. Overexpression of Ran in cells conferred a degree of protection against DM after 72h. Furthermore, interference with Ran significantly decrease cell viability. All of the above findings strongly imply that Ran may participate in the development of stress reaction to DM. Therefore, investigating the possible role of Ran in DM stress will broaden our limited knowledge regarding DM stress inducible genes. PMID:26924245

  18. Tubular up-regulation of clusterin mRNA in murine lupus-like nephritis.

    PubMed

    Moll, S; Menoud, P A; French, L; Sappino, A P; Pastore, Y; Schifferli, J A; Izui, S

    1998-04-01

    Clusterin, a widely distributed glycoprotein, is detected in most tissues and in numerous physiological fluids. In the kidney, this protein is constitutively expressed in tubular epithelial cells, and its expression is enhanced following tubular injuries. In addition, clusterin has been detected in glomerular immune deposits of glomerulonephritis. The present study was designed to define the sites of clusterin mRNA accumulation in murine lupus-like nephritis in comparison with murine tubulopathies. In lupus-like nephritis, a significant increase of clusterin mRNA abundance was demonstrated. This up-regulation was localized exclusively in tubular epithelial cells exhibiting tubulointerstitial alterations, whereas no clusterin mRNA was detectable in diseased glomeruli, excluding an active synthesis of clusterin by glomerular cells. A similar tubular increase of clusterin mRNA abundance was observed in myeloma-like cast nephropathy induced by IgG3 monoclonal cryoglobulins and even in the absence of any detectable histological alterations in a model of septic shock induced by the injection of bacterial lipopolysaccharides. Our results suggest that tubular epithelial cells are the only sites of clusterin mRNA accumulation during the course of lupus-like nephritis and that the tubular up-regulation of clusterin gene expression may reflect the cellular response to various types of tubular injuries.

  19. Slug inhibits the proliferation and tumor formation of human cervical cancer cells by up-regulating the p21/p27 proteins and down-regulating the activity of the Wnt/β-catenin signaling pathway via the trans-suppression Akt1/p-Akt1 expression

    PubMed Central

    Cui, Nan; Yang, Wen-Ting; Zheng, Peng-Sheng

    2016-01-01

    Slug (Snai2) has been demonstrated to act as an oncogene or tumor suppressor in different human cancers, but the function of Slug in cervical cancer remains poorly understood. In this study, we demonstrated that Slug could suppress the proliferation of cervical cancer cells in vitro and tumor formation in vivo. Further experiments found that Slug could trans-suppress the expression of Akt1/p-Akt1 by binding to E-box motifs in the promoter of the Akt1 gene and then inhibit the cell proliferation and tumor formation of cervical cancer cells by up-regulating p21/p27 and/or down-regulating the activity of the Wnt/β-catenin signaling pathway. Therefore, Slug acts as a tumor suppressor during cervical carcinogenesis. PMID:27036045

  20. Antagonism between MyD88- and TRIF-dependent signals in B7RP-1 up-regulation.

    PubMed

    Zhou, Zuping; Hoebe, Kasper; Du, Xin; Jiang, Zhengfan; Shamel, Louis; Beutler, Bruce

    2005-06-01

    Type I interferons (IFN) play a critical role in the Toll-like receptor (TLR)-mediated expression of B7 costimulatory family members. For example, LPS-induced up-regulation of CD80 (B7.1) and CD86 (B7.2) is abrogated in antigen-presenting cells (APC) deficient in TRIF or TRAM, two adaptors that are responsible for TLR4-mediated production of Type I IFN. In this report, we demonstrate that LPS-induced up-regulation of B7-related protein 1 (B7RP-1), a ligand for ICOS, is dependent primarily upon the MyD88-dependent signaling pathway. Signaling via the TRIF pathway sharply limits MyD88-dependent B7RP-1 up-regulation. Hence, LPS induces significantly higher B7RP-1 expression on TRIF- or TRAM-deficient mouse peritoneal macrophages and on TRIF-deficient mouse splenic B cells as compared to wild-type cells. Further studies reveal that Type I IFN are general suppressors of TLR-mediated up-regulation of B7RP-1. These data indicate that Type I IFN play a dual role in the TLR-mediated expression of B7 costimulatory family members and suggest that they may act to limit B7RP-1 expression and thus limit signals derived from B7RP-1-ICOS interaction.

  1. Up-Regulation of Nerve Growth Factor in Cholestatic Livers and Its Hepatoprotective Role against Oxidative Stress

    PubMed Central

    Tsai, Ming-Shian; Lin, Yu-Chun; Sun, Cheuk-Kwan; Huang, Shih-Che; Lee, Po-Huang; Kao, Ying-Hsien

    2014-01-01

    The role of nerve growth factor (NGF) in liver injury induced by bile duct ligation (BDL) remains elusive. This study aimed to investigate the relationship between inflammation and hepatic NGF expression, to explore the possible upstream molecules up-regulating NGF, and to determine whether NGF could protect hepatocytes from oxidative liver injury. Biochemical and molecular detection showed that NGF was up-regulated in cholestatic livers and plasma, and well correlated with systemic and hepatic inflammation. Conversely, systemic immunosuppression reduced serum NGF levels and resulted in higher mortality in BDL-treated mice. Immunohistochemistry showed that the up-regulated NGF was mainly localized in parenchymal hepatocytes. In vitro mechanistic study further demonstrated that TGF-β1 up-regulated NGF expression in clone-9 and primary rat hepatocytes. Exogenous NGF supplementation and endogenous NGF overexpression effectively protected hepatocytes against TGF-β1- and oxidative stress-induced cell death in vitro, along with reduced formation of oxidative adducted proteins modified by 4-HNE and 8-OHdG. TUNEL staining confirmed the involvement of anti-apoptosis in the NGF-exhibited hepatoprotection. Moreover, NGF potently induced Akt phosphorylation and increased Bcl-2 to Bax ratios, whereas these molecular alterations by NGF were only seen in the H2O2-, but not TGF-β1-treated hepatocytes. In conclusion, NGF exhibits anti-oxidative and hepatoprotective effects and is suggested to be therapeutically applicable in treating cholestatic liver diseases. PMID:25397406

  2. Spatial coordination between chromosomes and cell division proteins in Escherichia coli.

    PubMed

    Männik, Jaan; Bailey, Matthew W

    2015-01-01

    To successfully propagate, cells need to coordinate chromosomal replication and segregation with cell division to prevent formation of DNA-less cells and cells with damaged DNA. Here, we review molecular systems in Escherichia coli that are known to be involved in positioning the divisome and chromosome relative to each other. Interestingly, this well-studied micro-organism has several partially redundant mechanisms to achieve this task; none of which are essential. Some of these systems determine the localization of the divisome relative to chromosomes such as SlmA-dependent nucleoid occlusion, some localize the chromosome relative to the divisome such as DNA translocation by FtsK, and some are likely to act on both systems such as the Min system and newly described Ter linkage. Moreover, there is evidence that E. coli harbors other divisome-chromosome coordination systems in addition to those known. The review also discusses the minimal requirements of coordination between chromosomes and cell division proteins needed for cell viability. Arguments are presented that cells can propagate without any dedicated coordination between their chromosomes and cell division machinery at the expense of lowered fitness. PMID:25926826

  3. Spatial coordination between chromosomes and cell division proteins in Escherichia coli

    PubMed Central

    Männik, Jaan; Bailey, Matthew W.

    2015-01-01

    To successfully propagate, cells need to coordinate chromosomal replication and segregation with cell division to prevent formation of DNA-less cells and cells with damaged DNA. Here, we review molecular systems in Escherichia coli that are known to be involved in positioning the divisome and chromosome relative to each other. Interestingly, this well-studied micro-organism has several partially redundant mechanisms to achieve this task; none of which are essential. Some of these systems determine the localization of the divisome relative to chromosomes such as SlmA-dependent nucleoid occlusion, some localize the chromosome relative to the divisome such as DNA translocation by FtsK, and some are likely to act on both systems such as the Min system and newly described Ter linkage. Moreover, there is evidence that E. coli harbors other divisome-chromosome coordination systems in addition to those known. The review also discusses the minimal requirements of coordination between chromosomes and cell division proteins needed for cell viability. Arguments are presented that cells can propagate without any dedicated coordination between their chromosomes and cell division machinery at the expense of lowered fitness. PMID:25926826

  4. The yeast PNC1 longevity gene is up-regulated by mRNA mistranslation.

    PubMed

    Silva, Raquel M; Duarte, Iven C N; Paredes, João A; Lima-Costa, Tatiana; Perrot, Michel; Boucherie, Hélian; Goodfellow, Brian J; Gomes, Ana C; Mateus, Denisa D; Moura, Gabriela R; Santos, Manuel A S

    2009-01-01

    Translation fidelity is critical for protein synthesis and to ensure correct cell functioning. Mutations in the protein synthesis machinery or environmental factors that increase synthesis of mistranslated proteins result in cell death and degeneration and are associated with neurodegenerative diseases, cancer and with an increasing number of mitochondrial disorders. Remarkably, mRNA mistranslation plays critical roles in the evolution of the genetic code, can be beneficial under stress conditions in yeast and in Escherichia coli and is an important source of peptides for MHC class I complex in dendritic cells. Despite this, its biology has been overlooked over the years due to technical difficulties in its detection and quantification. In order to shed new light on the biological relevance of mistranslation we have generated codon misreading in Saccharomyces cerevisiae using drugs and tRNA engineering methodologies. Surprisingly, such mistranslation up-regulated the longevity gene PNC1. Similar results were also obtained in cells grown in the presence of amino acid analogues that promote protein misfolding. The overall data showed that PNC1 is a biomarker of mRNA mistranslation and protein misfolding and that PNC1-GFP fusions can be used to monitor these two important biological phenomena in vivo in an easy manner, thus opening new avenues to understand their biological relevance.

  5. [Low dose benzo(a)pyrene up-regulated the transcription of HSP70 and HSP90 in Eisenia fetida].

    PubMed

    Zheng, Sen-Lin; Sun, Tie-Heng; Xiao, Hong; Qiu, Xiao-Yan; Song, Yu-Fang

    2008-02-01

    To search for the molecular biomarkers of sub-lethal polycyclic aromatic hydrocarbons (PAHs)-contamination of soil, the subtractive cDNA libraries of earthworm Eisenia fetida exposed to benzo(a)pyrene (BaP) in artificial soil were constructed by suppression subtractive hybridization. After sequencing and analyzing with basic local alignment search tool (BLAST), two clones matching heat shock protein 70 k Da (HSP70) and one clone matching heat shock protein 90 k Da (HSP90) were isolated from the up-regulated library, and subsequently, the up-regulation of HSP70 and HSP90 was verified by real-time PCR in E. fetida exposed to 0.1 mg x kg(-1) and 1.0 mg x kg(-1) BaP. It was indicated that these two newly identified HSPs in E. fetida were the potential molecular biomarkers for soil contamination monitoring.

  6. Localization of a filarial phosphate permease that is up-regulated in response to depletion of essential Wolbachia endobacteria.

    PubMed

    Arumugam, Sridhar; Hoerauf, Achim; Pfarr, Kenneth M

    2014-03-01

    Wolbachia of filarial nematodes are essential, obligate endobacteria. When depleted by doxycycline worm embryogenesis, larval development and worm survival are inhibited. The molecular basis governing the endosymbiosis between Wolbachia and their filarial host is still being deciphered. In rodent filarial nematode Litomosoides sigmodontis, a nematode encoded phosphate permease gene (Ls-ppe-1) was up-regulated at the mRNA level in response to Wolbachia depletion and this gene promises to have an important role in Wolbachia-nematode endosymbiosis. To further characterize this gene, the regulation of phosphate permease during Wolbachia depletion was studied at the protein level in L. sigmodontis and in the human filaria Onchocerca volvulus. And the localization of phosphate permease (PPE) and Wolbachia in L. sigmodontis and O. volvulus was investigated in untreated and antibiotic treated worms. Depletion of Wolbachia by tetracycline (Tet) resulted in up-regulation of Ls-ppe-1 in L. sigmodontis. On day 36 of Tet treatment, compared to controls (Con), >98% of Wolbachia were depleted with a 3-fold increase in mRNA levels of Ls-ppe-1. Anti-Ls-PPE serum used in Western blots showed up-regulation of Ls-PPE at the protein level in Tet worms on day 15 and 36 of treatment. Immunohistology revealed the localization of Wolbachia and Ls-PPE in the embryos, microfilariae and hypodermis of L. sigmodontis female worms and up-regulation of Ls-PPE in response to Wolbachia depletion. Expression of O. volvulus phosphate permease (Ov-PPE) studied using anti-Ov-PPE serum, showed up-regulation of Ov-PPE at the protein level in doxycycline treated Wolbachia depleted O. volvulus worms and immunohistology revealed localization of Ov-PPE and Wolbachia and up-regulation of Ov-PPE in the hypodermis and embryos of doxycycline treated worms. Ls-PPE and Ov-PPE are upregulated upon Wolbachia depletion in same tissues and regions where Wolbachia are located in untreated worms, reinforcing a link

  7. Up-regulation of vimentin expression during regeneration in the adult fish brain.

    PubMed

    Clint, Sorcha C; Zupanc, Günther K H

    2002-03-01

    In contrast to mammals, the brains of teleost fish exhibit an enormous regenerative capacity following injury. Here, we have examined the potential role of vimentin in this wound healing. Fifteen days after application of a mechanical lesion to the corpus cerebelli in the teleost fish Apteronotus leptoryhnchus, the areal density of vimentin-positive fibres increased significantly at the lesion site and in the remaining ipsilateral molecular layer. This density remained elevated throughout the time period of up to 100 days examined. Based on this spatio-temporal pattern of vimentin up-regulation we propose that this intermediate filament protein is involved in the survival, differentiation, and/or dendritic growth of the new cells that replace damaged cells in the injury zone.

  8. A novel transcript is up-regulated by fasting in the hypothalamus and enhances insulin signaling

    PubMed Central

    Chai, Biaoxin; Li, Ji-Yao; Fritze, Danielle; Zhang, Weizhen; Xia, Zefeng; Mulholland, Michael W

    2015-01-01

    A transcript of unknown function, regulated by fasting and feeding, was identified by microarray analysis. The transcript is up-regulated in the fasting state. An 1168 base-pair cDNA was cloned from rat hypothalamus and sequenced. This sequence is consistent with adipogenesis downregulating transcript 3 (AGD3) (also known as human OCC-1) mRNA. A protein sequence identical to AGD3 was determined by mass spectrometry. In rat brain, AGD3 mRNA is distributed in arcuate nucleus, ventromedial hypothalamus, amygdaloid nuclei, paraventricular nucleus (PVN), hippocampus, and somatic cortex. Double in situ hybridization showed that AGD3 mRNA is co-localized with pro-opiomelanocortin and neuropeptide Y in arcuate nucleus neurons. AGD3 binds with insulin receptor substrate 4 and increases insulin-stimulated phospho-AKT and regulates AMPK and mTOR downstream target S6 kinase phosphorylation. PMID:22935015

  9. Nicotine activates and up-regulates nicotinic acetylcholine receptors in bronchial epithelial cells.

    PubMed

    Fu, Xiao Wen; Lindstrom, Jon; Spindel, Eliot R

    2009-07-01

    Prenatal nicotine exposure impairs normal lung development and leads to diminished pulmonary function after birth. Previous work from our laboratory has demonstrated that nicotine alters lung development by affecting a nonneuronal cholinergic autocrine loop that is expressed in lung. Bronchial epithelial cells (BECs) express choline acetyltransferase, the choline high-affinity transporter and nicotinic acetylcholine (ACh) receptor (nAChR) subunits. We now demonstrate through a combination of morphological and electrophysiological techniques that nicotine affects this autocrine loop by up-regulating and activating cholinergic signaling. RT-PCR showed the expression of alpha 3, alpha 4, alpha 7, alpha 9, alpha 10, beta2, and beta 4 nAChR mRNAs in rhesus monkey lung and cultured BECs. The expression of alpha 7, alpha 4, and beta2 nAChR was confirmed by immunofluorescence in the cultured BECs and lung. The electrophysiological characteristics of nAChR in BECs were determined using whole-cell patch-clamp on cultured BECs. Both ACh and nicotine evoked an inward current, with a rapid desensitizing current. Nicotine induced inward currents in a concentration-dependent manner, with an EC(50) of 26.7 microM. Nicotine-induced currents were reversibly blocked by the nicotinic antagonists, mecamylamine, dihydro-beta-erythroidine, and methyllcaconitine. Incubation of BECs with 1 microM nicotine for 48 hours enhanced nicotine-induced currents by roughly 26%. The protein tyrosine phosphorylation inhibitor, genistein, increased nicotine-induced currents by 58% and enhanced methyllcaconitine-sensitive currents (alpha 7 nAChR activities) 2.3-fold, whereas the protein tyrosine phosphatase inhibitor, pervanadate, decreased the effects of nicotine. These results demonstrate that chronic nicotine exposure up-regulates nAChR activity in developing lung, and that nAChR activity can be further modified by tyrosine phosphorylation.

  10. Low-Level Laser Irradiation Stimulates Tenocyte Migration with Up-Regulation of Dynamin II Expression

    PubMed Central

    Tsai, Wen-Chung; Hsu, Chih-Chin; Pang, Jong-Hwei S.; Lin, Miao-Sui; Chen, Ying-Hsun; Liang, Fang-Chen

    2012-01-01

    Low-level laser therapy (LLLT) is commonly used to treat sports-related tendinopathy or tendon injury. Tendon healing requires tenocyte migration to the repair site, followed by proliferation and synthesis of the extracellular matrix. This study was designed to determine the effect of laser on tenocyte migration. Furthermore, the correlation between this effect and expression of dynamin 2, a positive regulator of cell motility, was also investigated. Tenocytes intrinsic to rat Achilles tendon were treated with low-level laser (660 nm with energy density at 1.0, 1.5, and 2.0 J/cm2). Tenocyte migration was evaluated by an in vitro wound healing model and by transwell filter migration assay. The messenger RNA (mRNA) and protein expressions of dynamin 2 were determined by reverse transcription/real-time polymerase chain reaction (real-time PCR) and Western blot analysis respectively. Immunofluorescence staining was used to evaluate the dynamin 2 expression in tenocytes. Tenocytes with or without laser irradiation was treated with dynasore, a dynamin competitor and then underwent transwell filter migration assay. In vitro wound model revealed that more tenocytes with laser irradiation migrated across the wound border to the cell-free zone. Transwell filter migration assay confirmed that tenocyte migration was enhanced dose-dependently by laser. Real-time PCR and Western-blot analysis demonstrated that mRNA and protein expressions of dynamin 2 were up-regulated by laser irradiation dose-dependently. Confocal microscopy showed that laser enhanced the expression of dynamin 2 in cytoplasm of tenocytes. The stimulation effect of laser on tenocytes migration was suppressed by dynasore. In conclusion, low-level laser irradiation stimulates tenocyte migration in a process that is mediated by up-regulation of dynamin 2, which can be suppressed by dynasore. PMID:22666495

  11. Low-level laser irradiation stimulates tenocyte migration with up-regulation of dynamin II expression.

    PubMed

    Tsai, Wen-Chung; Hsu, Chih-Chin; Pang, Jong-Hwei S; Lin, Miao-Sui; Chen, Ying-Hsun; Liang, Fang-Chen

    2012-01-01

    Low-level laser therapy (LLLT) is commonly used to treat sports-related tendinopathy or tendon injury. Tendon healing requires tenocyte migration to the repair site, followed by proliferation and synthesis of the extracellular matrix. This study was designed to determine the effect of laser on tenocyte migration. Furthermore, the correlation between this effect and expression of dynamin 2, a positive regulator of cell motility, was also investigated. Tenocytes intrinsic to rat Achilles tendon were treated with low-level laser (660 nm with energy density at 1.0, 1.5, and 2.0 J/cm(2)). Tenocyte migration was evaluated by an in vitro wound healing model and by transwell filter migration assay. The messenger RNA (mRNA) and protein expressions of dynamin 2 were determined by reverse transcription/real-time polymerase chain reaction (real-time PCR) and Western blot analysis respectively. Immunofluorescence staining was used to evaluate the dynamin 2 expression in tenocytes. Tenocytes with or without laser irradiation was treated with dynasore, a dynamin competitor and then underwent transwell filter migration assay. In vitro wound model revealed that more tenocytes with laser irradiation migrated across the wound border to the cell-free zone. Transwell filter migration assay confirmed that tenocyte migration was enhanced dose-dependently by laser. Real-time PCR and Western-blot analysis demonstrated that mRNA and protein expressions of dynamin 2 were up-regulated by laser irradiation dose-dependently. Confocal microscopy showed that laser enhanced the expression of dynamin 2 in cytoplasm of tenocytes. The stimulation effect of laser on tenocytes migration was suppressed by dynasore. In conclusion, low-level laser irradiation stimulates tenocyte migration in a process that is mediated by up-regulation of dynamin 2, which can be suppressed by dynasore.

  12. The juxtamembrane domain in ETV6/FLT3 is critical for PIM-1 up-regulation and cell proliferation

    SciTech Connect

    Vu, Hoang Anh; Xinh, Phan Thi; Kano, Yasuhiko; Tokunaga, Katsushi; Sato, Yuko

    2009-06-05

    We recently reported that the ETV6/FLT3 fusion protein conferred interleukin-3-independent growth on Ba/F3 cells. The present study has been conducted to assess role of the juxtamembrane domain of FLT3 for signal transduction and cell transformation. The wild-type ETV6/FLT3 fusion protein in transfected cells was a constitutively activated tyrosine kinase that led to up-regulation of PIM-1 and activations of STAT5, AKT, and MAPK. Deletion of the juxtamembrane domain abrogated interleukin-3-independent growth of the transfected cells and PIM-1 up-regulation, whereas it retained compatible levels of phosphorylations of STAT5, AKT, and MAPK. Further deletion of N-terminal region of the tyrosine kinase I domain of FLT3 completely abolished these phosphorylations. Our data indicate that the juxtamembrane domain of FLT3 in ETV6/FLT3 fusion protein is critical for cell proliferation and PIM-1 up-regulation that might be independent of a requirement for signaling through STAT5, MAPK, and AKT pathways.

  13. Nicotinic acetylcholine receptors containing alpha 7 subunits on rat cortical neurons do not undergo long-lasting inactivation even when up-regulated by chronic nicotine exposure.

    PubMed

    Kawai, H; Berg, D K

    2001-09-01

    Chronic exposure to (-)nicotine has been widely reported to up-regulate nicotinic acetylcholine receptors on neurons and induce long-term inactivation as a possible cause. Nicotinic receptors containing alpha 7 subunits are among the most abundant in brain and influence diverse cellular events. Whole-cell patch clamp recording from embryonic rat cortical neurons in culture was used to identify responses from alpha 7-containing receptors. Immunochemical staining for glutamic acid decarboxylase (GAD) indicated that both GABAergic and non-GABAergic neurons expressed the receptors. Exposure to micromolar concentrations of nicotine for 1-4 days caused up-regulation of the receptors as measured by [alpha-(125)I]-bungarotoxin binding. Carbachol produced the same up-regulation, and cell counts demonstrated that neuronal survival was unchanged. The up-regulation was accompanied by an increased whole-cell response; no evidence was found for long-lasting inactivation. Autonomic alpha 7-containing receptors also avoided long-lasting inactivation, even though the receptors were down-regulated by nicotine. Blocking protein synthesis or protein glycosylation prevented receptor up-regulation on cortical neurons, suggesting that new synthesis was required. No evidence was found for a pre-existing intracellular pool that supplied receptors to the surface. The results indicate that alpha 7-containing receptors differ from other receptor subtypes in their regulation by nicotine and demonstrate further that long-lasting inactivation is not an obligatory requirement for up-regulation in this case.

  14. HPV E1 up-regulates replication-related biochemistries of AAV Rep78.

    PubMed

    Bandyopadhyay, Sarmistha; Cao, Maohua; Liu, Yong; Hermonat, Paul L

    2010-06-20

    Human papillomavirus type 16 (HPV) E1 protein provides helper function for the adeno-associated virus type 2 (AAV) life cycle. E1 is the replication protein of HPV, analogous to AAV Rep78, but without the endonuclease/covalent attachment activity of Rep78. Previously we have shown that E1 and Rep78 interact in vitro. Here we investigated E1's effects on Rep78 interaction with AAV's inverted terminal repeat (ITR) DNA in vitro, using purified Rep78 and E1 proteins from bacteria. E1 enhanced Rep78-ITR binding, ATPase activity, Rep78-ITR-covalent linkage and Rep78-ITR-endonuclease activity (central to AAV replication). These enhancements occurred in a dose-dependent manner whenever assayed. However, overall Rep78-plus-E1 helicase activity was lower than Rep78's helicase activity. These data suggest that E1's broad-based helper function for the AAV life cycle (AAV DNA, mRNA, and protein levels are up-regulated by E1) is likely through its ability to enhance Rep78's critical replication-required biochemistries on ITR DNA.

  15. Infected cell protein 0 functional domains and their coordination in herpes simplex virus replication

    PubMed Central

    Gu, Haidong

    2016-01-01

    Herpes simplex virus 1 (HSV-1) is a ubiquitous human pathogen that establishes latent infection in ganglia neurons. Its unique life cycle requires a balanced “conquer and compromise” strategy to deal with the host anti-viral defenses. One of HSV-1 α (immediate early) gene products, infected cell protein 0 (ICP0), is a multifunctional protein that interacts with and modulates a wide range of cellular defensive pathways. These pathways may locate in different cell compartments, which then migrate or exchange factors upon stimulation, for the purpose of a concerted and effective defense. ICP0 is able to simultaneously attack multiple host pathways by either degrading key restrictive factors or modifying repressive complexes. This is a viral protein that contains an E3 ubiquitin ligase, translocates among different cell compartments and interacts with major defensive complexes. The multiple functional domains of ICP0 can work independently and at the same time coordinate with each other. Dissecting the functional domains of ICP0 and delineating the coordination of these domains will help us understand HSV-1 pathogenicity as well as host defense mechanisms. This article focuses on describing individual ICP0 domains, their biochemical properties and their implication in HSV-1 infection. By putting individual domain functions back into the picture of host anti-viral defense network, this review seeks to elaborate the complex interactions between HSV-1 and its host. PMID:26870669

  16. Producing High-Accuracy Lattice Models from Protein Atomic Coordinates Including Side Chains

    PubMed Central

    Mann, Martin; Saunders, Rhodri; Smith, Cameron; Backofen, Rolf; Deane, Charlotte M.

    2012-01-01

    Lattice models are a common abstraction used in the study of protein structure, folding, and refinement. They are advantageous because the discretisation of space can make extensive protein evaluations computationally feasible. Various approaches to the protein chain lattice fitting problem have been suggested but only a single backbone-only tool is available currently. We introduce LatFit, a new tool to produce high-accuracy lattice protein models. It generates both backbone-only and backbone-side-chain models in any user defined lattice. LatFit implements a new distance RMSD-optimisation fitting procedure in addition to the known coordinate RMSD method. We tested LatFit's accuracy and speed using a large nonredundant set of high resolution proteins (SCOP database) on three commonly used lattices: 3D cubic, face-centred cubic, and knight's walk. Fitting speed compared favourably to other methods and both backbone-only and backbone-side-chain models show low deviation from the original data (~1.5 Å RMSD in the FCC lattice). To our knowledge this represents the first comprehensive study of lattice quality for on-lattice protein models including side chains while LatFit is the only available tool for such models. PMID:22934109

  17. Producing high-accuracy lattice models from protein atomic coordinates including side chains.

    PubMed

    Mann, Martin; Saunders, Rhodri; Smith, Cameron; Backofen, Rolf; Deane, Charlotte M

    2012-01-01

    Lattice models are a common abstraction used in the study of protein structure, folding, and refinement. They are advantageous because the discretisation of space can make extensive protein evaluations computationally feasible. Various approaches to the protein chain lattice fitting problem have been suggested but only a single backbone-only tool is available currently. We introduce LatFit, a new tool to produce high-accuracy lattice protein models. It generates both backbone-only and backbone-side-chain models in any user defined lattice. LatFit implements a new distance RMSD-optimisation fitting procedure in addition to the known coordinate RMSD method. We tested LatFit's accuracy and speed using a large nonredundant set of high resolution proteins (SCOP database) on three commonly used lattices: 3D cubic, face-centred cubic, and knight's walk. Fitting speed compared favourably to other methods and both backbone-only and backbone-side-chain models show low deviation from the original data (~1.5 Å RMSD in the FCC lattice). To our knowledge this represents the first comprehensive study of lattice quality for on-lattice protein models including side chains while LatFit is the only available tool for such models. PMID:22934109

  18. Producing high-accuracy lattice models from protein atomic coordinates including side chains.

    PubMed

    Mann, Martin; Saunders, Rhodri; Smith, Cameron; Backofen, Rolf; Deane, Charlotte M

    2012-01-01

    Lattice models are a common abstraction used in the study of protein structure, folding, and refinement. They are advantageous because the discretisation of space can make extensive protein evaluations computationally feasible. Various approaches to the protein chain lattice fitting problem have been suggested but only a single backbone-only tool is available currently. We introduce LatFit, a new tool to produce high-accuracy lattice protein models. It generates both backbone-only and backbone-side-chain models in any user defined lattice. LatFit implements a new distance RMSD-optimisation fitting procedure in addition to the known coordinate RMSD method. We tested LatFit's accuracy and speed using a large nonredundant set of high resolution proteins (SCOP database) on three commonly used lattices: 3D cubic, face-centred cubic, and knight's walk. Fitting speed compared favourably to other methods and both backbone-only and backbone-side-chain models show low deviation from the original data (~1.5 Å RMSD in the FCC lattice). To our knowledge this represents the first comprehensive study of lattice quality for on-lattice protein models including side chains while LatFit is the only available tool for such models.

  19. Coordinate regulation of proteins associated with radiation resistance in cultured insect cells

    SciTech Connect

    Rand, A.; Koval, T.M.

    1994-04-01

    Cultured TN-368 lepidopteran insect cells exhibit a pronounced resistance to the lethal effects of a variety of physical agents, including X rays and 254 nm UV light, as well as a large number of chemicals. The resistance to ionizing radiation has previously been associated with an inducible process which is not expressed in unirradiated cells or cells receiving less than some minimal amount of radiation necessary for activating the process. The studies in this paper were initiated in an attempt to identify and characterize the inducible proteins associated with the marked radiation resistance of the TN-368 cells. Cells were exposed to doses of 0, 25, 64 or 350 Gy of {sup 137}Cs {gamma} rays and incubated either for 3 h in medium containing [{sup 35}S]methionine or for 2 h without labeling. Labeled cells were separated into nuclear and cytoplasmic fractions and proteins were analyzed on two-dimensional polyacrylamide gels. Unlabeled cells were used to isolate total RNA which was translated in vitro in a rabbit reticulocyte lysate system with {sup 35}S label. These translation products were also analyzed by two-dimensional electrophoresis. Gamma irradiation of the TN-368 cells resulted in the de novo synthesis of several proteins as well as the complete inhibition of others. The number of such proteins identified was 19. These proteins ranged in size from 18-73 kDa, with a pI distribution of 4.7 to 6.1. In addition to the unique proteins, a large number of other proteins were also either up- or down-regulated. These observations were made in both nuclear and cytoplasmic fractions as well as in the translation products of RNA produced after irradiation. These studies indicate that RNA and protein synthesis in lepidopteran cells are coordinately regulated in response to ionizing radiation and may participate in the pronounced radioresistance of the TN-368 cells. 15 refs., 3 figs., 1 tab.

  20. NOD1 receptor is up-regulated in diabetic human and murine myocardium.

    PubMed

    Prieto, Patricia; Vallejo-Cremades, María Teresa; Benito, Gemma; González-Peramato, Pilar; Francés, Daniel; Agra, Noelia; Terrón, Verónica; Gónzalez-Ramos, Silvia; Delgado, Carmen; Ruiz-Gayo, Mariano; Pacheco, Ivette; Velasco-Martín, Juan P; Regadera, Javier; Martín-Sanz, Paloma; López-Collazo, Eduardo; Boscá, Lisardo; Fernández-Velasco, María

    2014-12-01

    Type 2 diabetes has a complex pathology that involves a chronic inflammatory state. Emerging evidence suggests a link between the innate immune system receptor NOD1 (nucleotide-binding and oligomerization domain 1) and the pathogenesis of diabetes, in monocytes and hepatic and adipose tissues. The aim of the present study was to assess the role of NOD1 in the progression of diabetic cardiomyopathy. We have measured NOD1 protein in cardiac tissue from Type 2 diabetic (db) mice. Heart and isolated cardiomyocytes from db mice revealed a significant increase in NOD1, together with an up-regulation of nuclear factor κB (NF-κB) and increased apoptosis. Heart tissue also exhibited an enhanced expression of pro-inflammatory cytokines. Selective NOD1 activation with C12-γ-D-glutamyl-m-diaminopimelic acid (iEDAP) resulted in an increased NF-κB activation and apoptosis, demonstrating the involvement of NOD1 both in wild-type and db mice. Moreover, HL-1 cardiomyocytes exposed to elevated concentrations of glucose plus palmitate displayed an enhanced NF-κB activity and apoptotic profile, which was prevented by silencing of NOD1 expression. To address this issue in human pathology, NOD1 expression was evaluated in myocardium obtained from patients with Type 2 diabetes (T2DMH) and from normoglycaemic individuals without cardiovascular histories (NH). We have found that NOD1 was expressed in both NH and T2DMH; however, NOD1 expression was significantly pronounced in T2DMH. Furthermore, both the pro-inflammatory cytokine tumour necrosis factor α (TNF-α) and the apoptosis mediator caspase-3 were up-regulated in T2DMH samples. Taken together, our results define an active role for NOD1 in the heightened inflammatory environment associated with both experimental and human diabetic cardiac disease.

  1. Mtr4-like protein coordinates nuclear RNA processing for heterochromatin assembly and for telomere maintenance

    PubMed Central

    Lee, Nathan N.; Chalamcharla, Venkata R.; Reyes-Turcu, Francisca; Mehta, Sameet; Zofall, Martin; Balachandran, Vanivilasini; Dhakshnamoorthy, Jothy; Taneja, Nitika; Yamanaka, Soichiro; Zhou, Ming; Grewal, Shiv I. S.

    2013-01-01

    SUMMARY The regulation of protein-coding and noncoding RNAs is linked to nuclear processes including chromatin modifications and gene silencing. However, the mechanisms that distinguish RNAs and mediate their functions are poorly understood. We describe a nuclear RNA processing network in fission yeast with a core module comprising the Mtr4-like protein, Mtl1, and the zinc finger protein, Red1. The Mtl1-Red1 core promotes degradation of mRNAs and noncoding RNAs, and associates with different proteins to assemble heterochromatin via distinct mechanisms. Mtl1 also forms Red1-independent interactions with evolutionarily conserved proteins named Nrl1 and Ctr1, which associate with splicing factors. Whereas Nrl1 targets transcripts with cryptic introns to form heterochromatin at developmental genes and retrotransposons, Ctr1 functions in processing intron-containing telomerase RNA. Together with our discovery of widespread cryptic introns, including in noncoding RNAs, these findings reveal unique cellular strategies for recognizing regulatory RNAs and coordinating their functions in response to developmental and environmental cues. PMID:24210919

  2. Up-regulation of the embryonic self-renewal network through reversible polyploidy in irradiated p53-mutant tumour cells

    SciTech Connect

    Salmina, Kristine; Jankevics, Eriks; Huna, Anda; Perminov, Dmitry; Radovica, Ilze; Klymenko, Tetyana; Ivanov, Andrey; Jascenko, Elina; Scherthan, Harry; Cragg, Mark; Erenpreisa, Jekaterina

    2010-08-01

    We have previously documented that transient polyploidy is a potential cell survival strategy underlying the clonogenic re-growth of tumour cells after genotoxic treatment. In an attempt to better define this mechanism, we recently documented the key role of meiotic genes in regulating the DNA repair and return of the endopolyploid tumour cells (ETC) to diploidy through reduction divisions after irradiation. Here, we studied the role of the pluripotency and self-renewal stem cell genes NANOG, OCT4 and SOX2 in this polyploidy-dependent survival mechanism. In irradiation-resistant p53-mutated lymphoma cell-lines (Namalwa and WI-L2-NS) but not sensitive p53 wild-type counterparts (TK6), low background expression of OCT4 and NANOG was up-regulated by ionising radiation with protein accumulation evident in ETC as detected by OCT4/DNA flow cytometry and immunofluorescence (IF). IF analysis also showed that the ETC generate PML bodies that appear to concentrate OCT4, NANOG and SOX2 proteins, which extend into complex nuclear networks. These polyploid tumour cells resist apoptosis, overcome cellular senescence and undergo bi- and multi-polar divisions transmitting the up-regulated OCT4, NANOG and SOX2 self-renewal cassette to their descendents. Altogether, our observations indicate that irradiation-induced ETC up-regulate key components of germ-line cells, which potentially facilitate survival and propagation of the tumour cell population.

  3. Isoform-Specific Up-Regulation of Plasma Membrane Ca2+ATPase Expression During Colon and Gastric Cancer Cell Differentiation

    PubMed Central

    Ribiczey, Polett; Tordai, Attila; Andrikovics, Hajnalka; Filoteo, Adelaida G.; Penniston, John T.; Enouf, Jocelyne; Enyedi, Ágnes; Papp, Béla; Kovács, Tünde

    2007-01-01

    Summary In this work we demonstrate a differentiation-induced up-regulation of the expression of plasma membrane Ca2+ATPase (PMCA) isoforms being present in various gastric/colon cancer cell types. We found PMCA1b as the major isoform in non-differentiated cancer cell lines, whereas the expression level of PMCA4b was significantly lower. Cell differentiation initiated with short chain fatty acids (SCFAs) and trichostatin A, or spontaneous differentiation of post-confluent cell cultures resulted in a marked induction of PMCA4b expression, while only moderately increased PMCA1b levels. Up-regulation of PMCA4b expression was demonstrated both at the protein and mRNA levels, and closely correlated with the induction of established differentiation markers. In contrast, the expression level of the Na+/K+-ATPase or that of the sarco/endoplasmic reticulum Ca2+ATPase 2 protein did not change significantly under these conditions. In membrane vesicles obtained from SCFA-treated gastric/colon cancer cells a marked increase in the PMCA-dependent Ca2+ transport activity was observed, indicating a general increase of PMCA function during the differentiation of these cancer cells. Because various PMCA isoforms display distinct functional characteristics, we suggest that up-regulated PMCA expression, together with a major switch in PMCA isoform pattern may significantly contribute to the differentiation of gastric/colon cancer cells. The analysis of PMCA expression may provide a new diagnostic tool for monitoring the tumor phenotype. PMID:17433436

  4. A model for protocellular coordination of nucleic acid and protein syntheses

    NASA Technical Reports Server (NTRS)

    Fox, S. W.

    1981-01-01

    The proteinoid model for the coordination of protein synthesis with nucleic acid coding within the evolving protocell is discussed. Evidence for the self-ordering of amino acid chains, which would enhance the catalytic activity of a lysine-rich proteinoid, is presented, along with that for the preferential formation of microparticles, particularly proteinoid microparticles, in various solutions. Demonstrations of the catalytic activity of lysine-rich proteinoids in the synthesis of peptide and internucleotide bonds are pointed out. The view of evolution as a two stage sequence in which the geological synthesis of peptides evolved to the protocellular synthesis of peptides and oligonucleotides is discussed, and contrasted with the alternative view, in accord with the central dogma, that nucleic acids arose first then governed the production of proteins and protocells.

  5. Ischemic postconditioning protects against ischemic brain injury by up-regulation of acid-sensing ion channel 2a

    PubMed Central

    Duanmu, Wang-sheng; Cao, Liu; Chen, Jing-yu; Ge, Hong-fei; Hu, Rong; Feng, Hua

    2016-01-01

    Ischemic postconditioning renders brain tissue tolerant to brain ischemia, thereby alleviating ischemic brain injury. However, the exact mechanism of action is still unclear. In this study, a rat model of global brain ischemia was subjected to ischemic postconditioning treatment using the vessel occlusion method. After 2 hours of ischemia, the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds. This procedure was repeated six times. Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia, and up-regulate acid-sensing ion channel 2a expression at the mRNA and protein level. These findings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippocampus after global brain ischemia, which promotes neuronal tolerance to ischemic brain injury. PMID:27212927

  6. HDAC up-regulation in early colon field carcinogenesis is involved in cell tumorigenicity through regulation of chromatin structure.

    PubMed

    Stypula-Cyrus, Yolanda; Damania, Dhwanil; Kunte, Dhananjay P; Cruz, Mart Dela; Subramanian, Hariharan; Roy, Hemant K; Backman, Vadim

    2013-01-01

    Normal cell function is dependent on the proper maintenance of chromatin structure. Regulation of chromatin structure is controlled by histone modifications that directly influence chromatin architecture and genome function. Specifically, the histone deacetylase (HDAC) family of proteins modulate chromatin compaction and are commonly dysregulated in many tumors, including colorectal cancer (CRC). However, the role of HDAC proteins in early colorectal carcinogenesis has not been previously reported. We found HDAC1, HDAC2, HDAC3, HDAC5, and HDAC7 all to be up-regulated in the field of human CRC. Furthermore, we observed that HDAC2 up-regulation is one of the earliest events in CRC carcinogenesis and observed this in human field carcinogenesis, the azoxymethane-treated rat model, and in more aggressive colon cancer cell lines. The universality of HDAC2 up-regulation suggests that HDAC2 up-regulation is a novel and important early event in CRC, which may serve as a biomarker. HDAC inhibitors (HDACIs) interfere with tumorigenic HDAC activity; however, the precise mechanisms involved in this process remain to be elucidated. We confirmed that HDAC inhibition by valproic acid (VPA) targeted the more aggressive cell line. Using nuclease digestion assays and transmission electron microscopy imaging, we observed that VPA treatment induced greater changes in chromatin structure in the more aggressive cell line. Furthermore, we used the novel imaging technique partial wave spectroscopy (PWS) to quantify nanoscale alterations in chromatin. We noted that the PWS results are consistent with the biological assays, indicating a greater effect of VPA treatment in the more aggressive cell type. Together, these results demonstrate the importance of HDAC activity in early carcinogenic events and the unique role of higher-order chromatin structure in determining cell tumorigenicity.

  7. Up-regulation of stomatin expression by hypoxia and glucocorticoid stabilizes membrane-associated actin in alveolar epithelial cells

    PubMed Central

    Chen, Ji-Cheng; Cai, Hao-Yu; Wang, Yan; Ma, Yuan-Yuan; Song, Liang-Nian; Yin, Li-Juan; Cao, Dong-Mei; Diao, Fei; Li, Yi-Dong; Lu, Jian

    2013-01-01

    Stomatin is an important lipid raft-associated protein which interacts with membrane proteins and plays a role in the membrane organization. However, it is unknown whether it is involved in the response to hypoxia and glucocorticoid (GC) in alveolar epithelial cells (AEC). In this study we found that hypoxia and dexamethasone (dex), a synthetic GC not only up-regulated the expression of stomatin alone, but also imposed additive effect on the expression of stomatin in A549 cells, primary AEC and lung of rats. Then we investigated whether hypoxia and dex transcriptionally up-regulated the expression of stomatin by reporter gene assay, and found that dex, but not hypoxia could increase the activity of a stomatin promoter-driven reporter gene. Further deletion and mutational studies demonstrated that a GC response element (GRE) within the promoter region mainly contributed to the induction of stomatin by dex. Moreover, we found that hypoxia exposure did not affect membrane-associated actin, but decreased actin in cytoplasm in A549 cells. Inhibiting stomatin expression by stomatin siRNA significantly decreased dense of peripheral actin ring in hypoxia or dex treated A549 cells. Taken all together, these data indicated that dex and/or hypoxia significantly up-regulated the expression of stomatin in vivo and in vitro, which could stabilize membrane-associated actin in AEC. We suppose that the up-regulation of stomatin by hypoxia and dex may enhance the barrier function of alveolar epithelia and mediate the adaptive role of GC to hypoxia. PMID:23672602

  8. Isolation and characterization of a novel gene sfig in rat skeletal muscle up-regulated by spaceflight (STS-90)

    NASA Technical Reports Server (NTRS)

    Kano, Mihoko; Kitano, Takako; Ikemoto, Madoka; Hirasaka, Katsuya; Asanoma, Yuki; Ogawa, Takayuki; Takeda, Shinichi; Nonaka, Ikuya; Adams, Gregory R.; Baldwin, Kenneth M.; Oarada, Motoko; Kishi, Kyoichi; Nikawa, Takeshi

    2003-01-01

    We obtained the skeletal muscle of rats exposed to weightless conditions during a 16-day-spaceflight (STS-90). By using a differential display technique, we identified 6 up-regulated and 3 down-regulated genes in the gastrocnemius muscle of the spaceflight rats, as compared to the ground control. The up-regulated genes included those coding Casitas B-lineage lymphoma-b, insulin growth factor binding protein-1, titin and mitochondrial gene 16 S rRNA and two novel genes (function unknown). The down-regulated genes included those encoding RNA polymerase II elongation factor-like protein, NADH dehydrogenase and one novel gene (function unknown). In the present study, we isolated and characterized one of two novel muscle genes that were remarkably up-regulated by spaceflight. The deduced amino acid sequence of the spaceflight-induced gene (sfig) comprises 86 amino acid residues and is well conserved from Drosophila to Homo sapiens. A putative leucine-zipper structure located at the N-terminal region of sfig suggests that this gene may encode a transcription factor. The up-regulated expression of this gene, confirmed by Northern blot analysis, was observed not only in the muscles of spaceflight rats but also in the muscles of tail-suspended rats, especially in the early stage of tail-suspension when gastrocnemius muscle atrophy initiated. The gene was predominantly expressed in the kidney, liver, small intestine and heart. When rat myoblastic L6 cells were grown to 100% confluence in the cell culture system, the expression of sfig was detected regardless of the cell differentiation state. These results suggest that spaceflight has many genetic effects on rat skeletal muscle.

  9. Coordination of Hepatitis C Virus Assembly by Distinct Regulatory Regions in Nonstructural Protein 5A

    PubMed Central

    Zayas, Margarita; Long, Gang; Madan, Vanesa; Bartenschlager, Ralf

    2016-01-01

    Hepatitis C virus (HCV) nonstructural protein (NS)5A is a RNA-binding protein composed of a N-terminal membrane anchor, a structured domain I (DI) and two intrinsically disordered domains (DII and DIII) interacting with viral and cellular proteins. While DI and DII are essential for RNA replication, DIII is required for assembly. How these processes are orchestrated by NS5A is poorly understood. In this study, we identified a highly conserved basic cluster (BC) at the N-terminus of DIII that is critical for particle assembly. We generated BC mutants and compared them with mutants that are blocked at different stages of the assembly process: a NS5A serine cluster (SC) mutant blocked in NS5A-core interaction and a mutant lacking the envelope glycoproteins (ΔE1E2). We found that BC mutations did not affect core-NS5A interaction, but strongly impaired core–RNA association as well as virus particle envelopment. Moreover, BC mutations impaired RNA-NS5A interaction arguing that the BC might be required for loading of core protein with viral RNA. Interestingly, RNA-core interaction was also reduced with the ΔE1E2 mutant, suggesting that nucleocapsid formation and envelopment are coupled. These findings argue for two NS5A DIII determinants regulating assembly at distinct, but closely linked steps: (i) SC-dependent recruitment of replication complexes to core protein and (ii) BC-dependent RNA genome delivery to core protein, triggering encapsidation that is tightly coupled to particle envelopment. These results provide a striking example how a single viral protein exerts multiple functions to coordinate the steps from RNA replication to the assembly of infectious virus particles. PMID:26727512

  10. Rac1-dependent transcriptional up-regulation of p27Kip1 by homophilic cell-cell contact in vascular endothelial cells.

    PubMed

    Hirano, Mayumi; Kanaide, Hideo; Hirano, Katsuya

    2007-10-01

    The mechanism for the transcriptional up-regulation of p27Kip1 due to the formation of the cell-cell contact was investigated in vascular endothelial cells. The induction of the cell-cell contact by adding an extra number of endothelial cells activated Rac1, up-regulated p27Kip1 mRNA and protein, and also facilitated the cell cycle arrest. Transduction of the Rac1 inhibitor protein using the cell-penetrating peptide or treatment with a Rac1 inhibitor NSC23766 inhibited the p27Kip1 up-regulation and delayed the cell cycle arrest. Rac1 was therefore suggested to mediate the contact-induced transcriptional up-regulation of p27Kip1. The role of Rac1 in the regulation of the p27Kip1 promoter activity was next examined with a luciferase reporter assay. The promoter activity was increased by inducing the cell-cell contact, which was significantly inhibited by the Rac1 inhibitory protein and NSC23766. The evaluation of various truncated promoter regions determined region -620 to -573 nucleotides from the initiation codon to be responsible for the contact-induced, Rac1-dependent activation of the p27Kip1 promoter. The present study thus demonstrated for the first time that the activation of Rac1 due to the cell-cell contact plays a critical role in the transcriptional up-regulation of p27Kip1 in vascular endothelial cells.

  11. NFAT5 Is Up-Regulated by Hypoxia: Possible Implications in Preeclampsia and Intrauterine Growth Restriction.

    PubMed

    Dobierzewska, Aneta; Palominos, Macarena; Irarrazabal, Carlos E; Sanchez, Marianela; Lozano, Mauricio; Perez-Sepulveda, Alejandra; Monteiro, Lara J; Burmeister, Yara; Figueroa-Diesel, Horacio; Rice, Gregory E; Illanes, Sebastian E

    2015-07-01

    During gestation, low oxygen environment is a major determinant of early placentation process, while persistent placental hypoxia leads to pregnancy-related complications such as preeclampsia (PE) and intrauterine growth restriction (IUGR). PE affects 5%-8% of all pregnancies worldwide and is a cause of maternal and fetal morbidity and mortality. During placental development, persistent hypoxia due to poor trophoblast invasion and reduced uteroplacental perfusion leads to maternal endothelial dysfunction and clinical manifestation of PE. Here we hypothesized that nuclear factor of activated T cells-5 (NFAT5), a well-known osmosensitive renal factor and recently characterized hypoxia-inducible protein, is also activated in vivo in placentas of PE and IUGR complications as well as in the in vitro model of trophoblast hypoxia. In JAR cells, low oxygen tension (1% O2) induced NFAT5 mRNA and increased its nuclear abundance, peaking at 16 h. This increase did not occur in parallel with the earlier HIF1A induction. Real-time PCR and Western blot analysis confirmed up-regulation of NFAT5 mRNA and NFAT5 nuclear content in human preeclamptic placentas and in rabbit placentas of an experimentally induced IUGR model, as compared with the control groups. In vitro lambda protein phosphatase (lambda PPase) treatment revealed that increased abundance of NFAT5 protein in nuclei of either JAR cells (16 h of hypoxia) or PE and IUGR placentas is at least partially due to NFAT5 phosphorylation. NFAT5 downstream targets aldose reductase (AR) and sodium-myo-inositol cotransporter (SMIT; official symbol SLC5A3) were not significantly up-regulated either in JAR cells exposed to hypoxia or in placentas of PE- and IUGR-complicated pregnancies, suggesting that hypoxia-dependent activation of NFAT5 serves as a separate function to its tonicity-dependent stimulation. In conclusion, we propose that NFAT5 may serve as a novel marker of placental hypoxia and ischemia independently of HIF1A. PMID

  12. The MAP kinase pathway coordinates crossover designation with disassembly of synaptonemal complex proteins during meiosis.

    PubMed

    Nadarajan, Saravanapriah; Mohideen, Firaz; Tzur, Yonatan B; Ferrandiz, Nuria; Crawley, Oliver; Montoya, Alex; Faull, Peter; Snijders, Ambrosius P; Cutillas, Pedro R; Jambhekar, Ashwini; Blower, Michael D; Martinez-Perez, Enrique; Harper, J Wade; Colaiacovo, Monica P

    2016-02-27

    Asymmetric disassembly of the synaptonemal complex (SC) is crucial for proper meiotic chromosome segregation. However, the signaling mechanisms that directly regulate this process are poorly understood. Here we show that the mammalian Rho GEF homolog, ECT-2, functions through the conserved RAS/ERK MAP kinase signaling pathway in the C. elegans germline to regulate the disassembly of SC proteins. We find that SYP-2, a SC central region component, is a potential target for MPK-1-mediated phosphorylation and that constitutively phosphorylated SYP-2 impairs the disassembly of SC proteins from chromosomal domains referred to as the long arms of the bivalents. Inactivation of MAP kinase at late pachytene is critical for timely disassembly of the SC proteins from the long arms, and is dependent on the crossover (CO) promoting factors ZHP-3/RNF212/Zip3 and COSA-1/CNTD1. We propose that the conserved MAP kinase pathway coordinates CO designation with the disassembly of SC proteins to ensure accurate chromosome segregation.

  13. The MAP kinase pathway coordinates crossover designation with disassembly of synaptonemal complex proteins during meiosis

    PubMed Central

    Nadarajan, Saravanapriah; Mohideen, Firaz; Tzur, Yonatan B; Ferrandiz, Nuria; Crawley, Oliver; Montoya, Alex; Faull, Peter; Snijders, Ambrosius P; Cutillas, Pedro R; Jambhekar, Ashwini; Blower, Michael D; Martinez-Perez, Enrique; Harper, J Wade; Colaiacovo, Monica P

    2016-01-01

    Asymmetric disassembly of the synaptonemal complex (SC) is crucial for proper meiotic chromosome segregation. However, the signaling mechanisms that directly regulate this process are poorly understood. Here we show that the mammalian Rho GEF homolog, ECT-2, functions through the conserved RAS/ERK MAP kinase signaling pathway in the C. elegans germline to regulate the disassembly of SC proteins. We find that SYP-2, a SC central region component, is a potential target for MPK-1-mediated phosphorylation and that constitutively phosphorylated SYP-2 impairs the disassembly of SC proteins from chromosomal domains referred to as the long arms of the bivalents. Inactivation of MAP kinase at late pachytene is critical for timely disassembly of the SC proteins from the long arms, and is dependent on the crossover (CO) promoting factors ZHP-3/RNF212/Zip3 and COSA-1/CNTD1. We propose that the conserved MAP kinase pathway coordinates CO designation with the disassembly of SC proteins to ensure accurate chromosome segregation. DOI: http://dx.doi.org/10.7554/eLife.12039.001 PMID:26920220

  14. Coordinate regulation of the mother centriole component nlp by nek2 and plk1 protein kinases.

    PubMed

    Rapley, Joseph; Baxter, Joanne E; Blot, Joelle; Wattam, Samantha L; Casenghi, Martina; Meraldi, Patrick; Nigg, Erich A; Fry, Andrew M

    2005-02-01

    Mitotic entry requires a major reorganization of the microtubule cytoskeleton. Nlp, a centrosomal protein that binds gamma-tubulin, is a G(2)/M target of the Plk1 protein kinase. Here, we show that human Nlp and its Xenopus homologue, X-Nlp, are also phosphorylated by the cell cycle-regulated Nek2 kinase. X-Nlp is a 213-kDa mother centriole-specific protein, implicating it in microtubule anchoring. Although constant in abundance throughout the cell cycle, it is displaced from centrosomes upon mitotic entry. Overexpression of active Nek2 or Plk1 causes premature displacement of Nlp from interphase centrosomes. Active Nek2 is also capable of phosphorylating and displacing a mutant form of Nlp that lacks Plk1 phosphorylation sites. Importantly, kinase-inactive Nek2 interferes with Plk1-induced displacement of Nlp from interphase centrosomes and displacement of endogenous Nlp from mitotic spindle poles, while active Nek2 stimulates Plk1 phosphorylation of Nlp in vitro. Unlike Plk1, Nek2 does not prevent association of Nlp with gamma-tubulin. Together, these results provide the first example of a protein involved in microtubule organization that is coordinately regulated at the G(2)/M transition by two centrosomal kinases. We also propose that phosphorylation by Nek2 may prime Nlp for phosphorylation by Plk1.

  15. Up regulated expression of tumour necrosis factor α converting enzyme in peripheral monocytes of patients with early systemic sclerosis

    PubMed Central

    Bohgaki, T; Amasaki, Y; Nishimura, N; Bohgaki, M; Yamashita, Y; Nishio, M; Sawada, K; Jodo, S; Atsumi, T; Koike, T

    2005-01-01

    Background: Systemic sclerosis (SSc) is accompanied by abnormalities in humoral and cellular immune systems. Objective: To determine the genes specifically expressed in the immune system in SSc by analysis of the gene expression profile of peripheral blood mononuclear cells (PBMC) from patients with SSc, including those treated with haematopoietic stem cell transplantation (HSCT). Additionally, to investigate the clinical significance of the up regulation of tumour necrosis factor α (TNFα) converting enzyme (TACE). Methods: PBMC from patients with SSc (n = 23) and other autoimmune diseases (systemic lupus erythematosus (SLE, n = 16), rheumatoid arthritis (RA, n = 29)), and from disease-free controls (n = 36) were examined. Complementary DNA arrays were used to evaluate gene expression of PBMC, in combination with real time quantitative polymerase chain reactions. TACE protein expression in PBMC was examined by fluorescence activated cell sorter (FACS). Results: In patients with SSc 118 genes were down regulated after HSCT. Subsequent comparative analysis of SSc without HSCT and healthy controls indicated SSc-specific up regulation for three genes: monocyte chemoattractant protein-3 (p = 0.0015), macrophage inflammatory protein 3α (p = 0.0339), and TACE (p = 0.0251). In the FACS analysis, TACE protein was mainly expressed on CD14+ monocytes both in patients with SSc and controls. TACE expression on CD14+ cells was significantly increased in patients with early SSc (p = 0.0096), but not in those with chronic SSc, SLE, or RA. TACE protein levels in SSc monocytes correlated with the intracellular CD68 levels (p = 0.0016). Conclusions: Up regulation of TACE expression was a unique profile in early SSc, and may affect the function of TNFα and other immunoregulatory molecules. PMID:16014681

  16. PPM1D controls nucleolar formation by up-regulating phosphorylation of nucleophosmin.

    PubMed

    Kozakai, Yuuki; Kamada, Rui; Furuta, Junya; Kiyota, Yuhei; Chuman, Yoshiro; Sakaguchi, Kazuyasu

    2016-01-01

    An increase of nucleolar number and size has made nucleoli essential markers for cytology and tumour development. However, the underlying basis for their structural integrity and abundance remains unclear. Protein phosphatase PPM1D was found to be up-regulated in different carcinomas including breast cancers. Here, we demonstrate for the first time that PPM1D regulates nucleolar formation via inducing an increased phosphorylation of the nucleolar protein NPM. We show that PPM1D overexpression induces an increase in the nucleolar number regardless of p53 status. We also demonstrated that specific sequential phosphorylation of NPM is important for nucleolar formation and that PPM1D is a novel upstream regulator of this phosphorylation pathway. These results enhance our understanding of the molecular mechanisms that govern nucleoli formation by demonstrating that PPM1D regulates nucleolar formation by regulating NPM phosphorylation status through a novel signalling pathway, PPM1D-CDC25C-CDK1-PLK1. PMID:27619510

  17. PPM1D controls nucleolar formation by up-regulating phosphorylation of nucleophosmin

    PubMed Central

    Kozakai, Yuuki; Kamada, Rui; Furuta, Junya; Kiyota, Yuhei; Chuman, Yoshiro; Sakaguchi, Kazuyasu

    2016-01-01

    An increase of nucleolar number and size has made nucleoli essential markers for cytology and tumour development. However, the underlying basis for their structural integrity and abundance remains unclear. Protein phosphatase PPM1D was found to be up-regulated in different carcinomas including breast cancers. Here, we demonstrate for the first time that PPM1D regulates nucleolar formation via inducing an increased phosphorylation of the nucleolar protein NPM. We show that PPM1D overexpression induces an increase in the nucleolar number regardless of p53 status. We also demonstrated that specific sequential phosphorylation of NPM is important for nucleolar formation and that PPM1D is a novel upstream regulator of this phosphorylation pathway. These results enhance our understanding of the molecular mechanisms that govern nucleoli formation by demonstrating that PPM1D regulates nucleolar formation by regulating NPM phosphorylation status through a novel signalling pathway, PPM1D-CDC25C-CDK1-PLK1. PMID:27619510

  18. Up-regulation of steroid biosynthesis by retinoid signaling: Implications for aging

    PubMed Central

    Manna, Pulak R.; Stetson, Cloyce L.; Daugherty, Carol; Shimizu, Ikue; Syapin, Peter J.; Garrel, Ghislaine; Cohen-Tannoudji, Joelle; Huhtaniemi, Ilpo; Slominski, Andrzej T.; Pruitt, Kevin; Stocco, Douglas M.

    2015-01-01

    Retinoids (vitamin A and its derivatives) are critical for a spectrum of developmental and physiological processes, in which steroid hormones also play indispensable roles. The StAR protein predominantly regulates steroid biosynthesis in steroidogenic tissues. We reported that regulation of retinoid, especially atRA and 9-cis RA, responsive StAR transcription is largely mediated by an LXR-RXR/RAR heterodimeric motif in the mouse StAR promoter. Herein we demonstrate that retinoids are capable of enhancing StAR protein, P-StAR, and steroid production, in granulosa, adrenocortical, glial, and epidermal cells. Whereas transient expression of RARα and RXRα enhanced 9-cis RA-treated StAR gene transcription, silencing of RXRα with siRNA, decreased StAR and steroid levels. An oligonucleotide probe encompassing an LXR-RXR/RAR motif bound to adrenocortical and epidermal keratinocyte NEs in EMSAs. ChIP studies revealed association of RARα and RXRα with the StAR proximal promoter. Further studies demonstrated that StAR mRNA levels decreased in diseased and elderly men and women skin tissues and that atRA could restore steroidogenesis in epidermal keratinocytes of aged individuals. These findings provide novel insights into the relevance of retinoid signaling in the up-regulation of steroid biosynthesis in various target tissues, and indicate that retinoid therapy may have important implications in age-related complications and diseases. PMID:26303142

  19. β₁-adrenergic receptor up-regulation induced by nadolol is mediated via signal transduction pathway coupled to α₁-adrenergic receptors.

    PubMed

    Mizuno, Koji; Kurokawa, Kazuhiro; Shibasaki, Masahiro; Ohkuma, Seitaro

    2011-09-26

    Although up-regulation of β-adrenergic receptors (β-ARs) occurs after long-term use of their antagonists in various tissues, the available data are little on mechanisms of β-AR up-regulation induced by their continuous blockade. The present study attempted to clarify mechanisms of β-AR up-regulation using mouse cerebral cortical neurons continuously exposed to nadolol (10 nM), a non-selective β-AR antagonist, for 24 h. Nadolol dose-dependently induced both subtypes of β-ARs, β₁- and β₂-ARs, which were not suppressed by protein A kinase inhibition with KT5720. On the other hand, blockade of α₁-ARs, which are immunohistochemically confirmed to be co-localized with β-ARs in the same neurons, significantly inhibited only β₁-AR up-regulation and the expression of β₂-ARs did not alter. In addition, phenylephrine, an agonist specific to α₁-ARs up-regulated β₁-ARs, but not β₂-ARs. Under the conditions with β-AR up-regulation, the level of phosphorylated protein kinase Cα (pPKCα) increased, which is significantly suppressed by prazosin, an α1-AR antagonist. Furthermore, nadolol decreased the degradation of mRNA of β₁-ARs, but not β₂-ARs. These results indicate that the nadolol-induced β₁-AR up-regulation is mediated via PKC-relating pathway via α₁-AR activation with stabilizing β₁-AR mRNA and that the increased expression of β₂-ARs is regulated by pathways different from those for β₁-AR expression.

  20. Proteolytic fragments of laminin promote excitotoxic neurodegeneration by up-regulation of the KA1 subunit of the kainate receptor.

    PubMed

    Chen, Zu-Lin; Yu, Huaxu; Yu, Wei-Ming; Pawlak, Robert; Strickland, Sidney

    2008-12-29

    Degradation of the extracellular matrix (ECM) protein laminin contributes to excitotoxic cell death in the hippocampus, but the mechanism of this effect is unknown. To study this process, we disrupted laminin gamma1 (lamgamma1) expression in the hippocampus. Lamgamma1 knockout (KO) and control mice had similar basal expression of kainate (KA) receptors, but the lamgamma1 KO mice were resistant to KA-induced neuronal death. After KA injection, KA1 subunit levels increased in control mice but were unchanged in lamgamma1 KO mice. KA1 levels in tissue plasminogen activator (tPA)-KO mice were also unchanged after KA, indicating that both tPA and laminin were necessary for KA1 up-regulation after KA injection. Infusion of plasmin-digested laminin-1 into the hippocampus of lamgamma1 or tPA KO mice restored KA1 up-regulation and KA-induced neuronal degeneration. Interfering with KA1 function with a specific anti-KA1 antibody protected against KA-induced neuronal death both in vitro and in vivo. These results demonstrate a novel pathway for neurodegeneration involving proteolysis of the ECM and KA1 KA receptor subunit up-regulation.

  1. GPR55, a G-protein coupled receptor for lysophosphatidylinositol, plays a role in motor coordination.

    PubMed

    Wu, Chia-Shan; Chen, Hongmei; Sun, Hao; Zhu, Jie; Jew, Chris P; Wager-Miller, James; Straiker, Alex; Spencer, Corinne; Bradshaw, Heather; Mackie, Ken; Lu, Hui-Chen

    2013-01-01

    The G-protein coupled receptor 55 (GPR55) is activated by lysophosphatidylinositols and some cannabinoids. Recent studies found prominent roles for GPR55 in neuropathic/inflammatory pain, cancer and bone physiology. However, little is known about the role of GPR55 in CNS development and function. To address this question, we performed a detailed characterization of GPR55 knockout mice using molecular, anatomical, electrophysiological, and behavioral assays. Quantitative PCR studies found that GPR55 mRNA was expressed (in order of decreasing abundance) in the striatum, hippocampus, forebrain, cortex, and cerebellum. GPR55 deficiency did not affect the concentrations of endocannabinoids and related lipids or mRNA levels for several components of the endocannabinoid system in the hippocampus. Normal synaptic transmission and short-term as well as long-term synaptic plasticity were found in GPR55 knockout CA1 pyramidal neurons. Deleting GPR55 function did not affect behavioral assays assessing muscle strength, gross motor skills, sensory-motor integration, motor learning, anxiety or depressive behaviors. In addition, GPR55 null mutant mice exhibited normal contextual and auditory-cue conditioned fear learning and memory in a Pavlovian conditioned fear test. In contrast, when presented with tasks requiring more challenging motor responses, GPR55 knockout mice showed impaired movement coordination. Taken together, these results suggest that GPR55 plays a role in motor coordination, but does not strongly regulate CNS development, gross motor movement or several types of learned behavior.

  2. Kinetic Detection of Orthogonal Protein and Chemical Coordinates in Enzyme Catalysis: Double Mutants of Soybean Lipoxygenase.

    PubMed

    Sharma, Sudhir C; Klinman, Judith P

    2015-09-01

    Soybean lipoxygenase-1 (SLO-1) is a paradigmatic enzyme system for studying the contribution of hydrogen tunneling to enzymatic proton-coupled electron transfer processes. In this study, the impact of pairs of double mutants on the properties of SLO-1 is presented. Steady-state rates and their deuterium kinetic isotope effects (KIEs) have been measured for the bimolecular reaction of enzyme with free substrate (kcat/Km) and compared to the unimolecular rate constant, kcat. A key kinetic finding is that the competitive KIEs on the second-order rate constant (kcat/Km) are all reduced from (D)kcat and, despite large changes in rate and activation parameters, remain essentially unaltered under a variety of conditions. These data implicate a protein reaction coordinate that is orthogonal to the chemical reaction coordinate and controls the concentration of the active enzyme. This study introduces a new means to interrogate the alteration of conformational landscapes that can occur following site-specific mutagenesis.

  3. GPR55, a G-Protein Coupled Receptor for Lysophosphatidylinositol, Plays a Role in Motor Coordination

    PubMed Central

    Wu, Chia-Shan; Chen, Hongmei; Sun, Hao; Zhu, Jie; Jew, Chris P.; Wager-Miller, James; Straiker, Alex; Spencer, Corinne; Bradshaw, Heather; Mackie, Ken; Lu, Hui-Chen

    2013-01-01

    The G-protein coupled receptor 55 (GPR55) is activated by lysophosphatidylinositols and some cannabinoids. Recent studies found prominent roles for GPR55 in neuropathic/inflammatory pain, cancer and bone physiology. However, little is known about the role of GPR55 in CNS development and function. To address this question, we performed a detailed characterization of GPR55 knockout mice using molecular, anatomical, electrophysiological, and behavioral assays. Quantitative PCR studies found that GPR55 mRNA was expressed (in order of decreasing abundance) in the striatum, hippocampus, forebrain, cortex, and cerebellum. GPR55 deficiency did not affect the concentrations of endocannabinoids and related lipids or mRNA levels for several components of the endocannabinoid system in the hippocampus. Normal synaptic transmission and short-term as well as long-term synaptic plasticity were found in GPR55 knockout CA1 pyramidal neurons. Deleting GPR55 function did not affect behavioral assays assessing muscle strength, gross motor skills, sensory-motor integration, motor learning, anxiety or depressive behaviors. In addition, GPR55 null mutant mice exhibited normal contextual and auditory-cue conditioned fear learning and memory in a Pavlovian conditioned fear test. In contrast, when presented with tasks requiring more challenging motor responses, GPR55 knockout mice showed impaired movement coordination. Taken together, these results suggest that GPR55 plays a role in motor coordination, but does not strongly regulate CNS development, gross motor movement or several types of learned behavior. PMID:23565223

  4. Up-regulation of the Sirtuin 1 (Sirt1) and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) genes in white adipose tissue of Id1 protein-deficient mice: implications in the protection against diet and age-induced glucose intolerance.

    PubMed

    Zhao, Ying; Ling, Flora; Griffin, Timothy M; He, Ting; Towner, Rheal; Ruan, Hong; Sun, Xiao-Hong

    2014-10-17

    Id1, a helix-loop-helix (HLH) protein that inhibits the function of basic HLH E protein transcription factors in lymphoid cells, has been implicated in diet- and age-induced obesity by unknown mechanisms. Here we show that Id1-deficient mice are resistant to a high fat diet- and age-induced obesity, as revealed by reduced weight gain and body fat, increased lipid oxidation, attenuated hepatosteatosis, lower levels of lipid droplets in brown adipose tissue, and smaller white adipocytes after a high fat diet feeding or in aged animals. Id1 deficiency improves glucose tolerance, lowers serum insulin levels, and reduces TNFα gene expression in white adipose tissue. Id1 deficiency also increased expression of Sirtuin 1 and peroxisome proliferator-activated receptor γ coactivator 1α, regulators of mitochondrial biogenesis and energy expenditure, in the white adipose tissue. This effect was accompanied by the elevation of several genes encoding proteins involved in oxidative phosphorylation and fatty acid oxidation, such as cytochrome c, medium-chain acyl-CoA dehydrogenase, and adipocyte protein 2. Moreover, the phenotype for Id1 deficiency was similar to that of mice expressing an E protein dominant-positive construct, ET2, suggesting that the balance between Id and E proteins plays a role in regulating lipid metabolism and insulin sensitivity. PMID:25190816

  5. The mitochondrial acyl carrier protein (ACP) coordinates mitochondrial fatty acid synthesis with iron sulfur cluster biogenesis

    PubMed Central

    Van Vranken, Jonathan G; Jeong, Mi-Young; Wei, Peng; Chen, Yu-Chan; Gygi, Steven P; Winge, Dennis R; Rutter, Jared

    2016-01-01

    Mitochondrial fatty acid synthesis (FASII) and iron sulfur cluster (FeS) biogenesis are both vital biosynthetic processes within mitochondria. In this study, we demonstrate that the mitochondrial acyl carrier protein (ACP), which has a well-known role in FASII, plays an unexpected and evolutionarily conserved role in FeS biogenesis. ACP is a stable and essential subunit of the eukaryotic FeS biogenesis complex. In the absence of ACP, the complex is destabilized resulting in a profound depletion of FeS throughout the cell. This role of ACP depends upon its covalently bound 4’-phosphopantetheine (4-PP)-conjugated acyl chain to support maximal cysteine desulfurase activity. Thus, it is likely that ACP is not simply an obligate subunit but also exploits the 4-PP-conjugated acyl chain to coordinate mitochondrial fatty acid and FeS biogenesis. DOI: http://dx.doi.org/10.7554/eLife.17828.001 PMID:27540631

  6. The mitochondrial acyl carrier protein (ACP) coordinates mitochondrial fatty acid synthesis with iron sulfur cluster biogenesis.

    PubMed

    Van Vranken, Jonathan G; Jeong, Mi-Young; Wei, Peng; Chen, Yu-Chan; Gygi, Steven P; Winge, Dennis R; Rutter, Jared

    2016-01-01

    Mitochondrial fatty acid synthesis (FASII) and iron sulfur cluster (FeS) biogenesis are both vital biosynthetic processes within mitochondria. In this study, we demonstrate that the mitochondrial acyl carrier protein (ACP), which has a well-known role in FASII, plays an unexpected and evolutionarily conserved role in FeS biogenesis. ACP is a stable and essential subunit of the eukaryotic FeS biogenesis complex. In the absence of ACP, the complex is destabilized resulting in a profound depletion of FeS throughout the cell. This role of ACP depends upon its covalently bound 4'-phosphopantetheine (4-PP)-conjugated acyl chain to support maximal cysteine desulfurase activity. Thus, it is likely that ACP is not simply an obligate subunit but also exploits the 4-PP-conjugated acyl chain to coordinate mitochondrial fatty acid and FeS biogenesis. PMID:27540631

  7. Dysfunctional chloroplasts up-regulate the expression of mitochondrial genes in Arabidopsis seedlings.

    PubMed

    Liao, Jo-Chien; Hsieh, Wei-Yu; Tseng, Ching-Chih; Hsieh, Ming-Hsiun

    2016-02-01

    Chloroplasts and mitochondria play important roles in maintaining metabolic and energy homeostasis in the plant cell. The interactions between these two organelles, especially photosynthesis and respiration, have been intensively studied. Still, little is known about the regulation of mitochondrial gene expression by chloroplasts and vice versa. The gene expression machineries in chloroplasts and mitochondria rely heavily on the nuclear genome. Thus, the interactions between nucleus and these organelles, including anterograde and retrograde regulation, have been actively investigated in the last two decades. Norflurazon (NF) and lincomycin (Lin) are two commonly used inhibitors to study chloroplast-to-nucleus retrograde signaling in plants. We used NF and Lin to block the development and functions of chloroplasts and examined their effects on mitochondrial gene expression, RNA editing and splicing. The editing of most mitochondrial transcripts was not affected, but the editing extents of nad4-107, nad6-103, and ccmFc-1172 decreased slightly in NF- and Lin-treated seedlings. While the splicing of mitochondrial transcripts was not significantly affected, steady-state mRNA levels of several mitochondrial genes increased significantly in NF- and Lin-treated seedlings. Moreover, Lin seemed to have more profound effects than NF on the expression of mitochondrial genes, indicating that signals derived from these two inhibitors might be distinct. NF and Lin also significantly induced the expression of nuclear genes encoding subunits of mitochondrial electron transport chain complexes. Thus, dysfunctional chloroplasts may coordinately up-regulate the expression of nuclear and mitochondrial genes encoding subunits of respiratory complexes.

  8. The Aspergillus fumigatus Damage Resistance Protein Family Coordinately Regulates Ergosterol Biosynthesis and Azole Susceptibility

    PubMed Central

    Song, Jinxing; Zhai, Pengfei; Zhang, Yuanwei; Zhang, Caiyun; Sang, Hong; Han, Guanzhu; Keller, Nancy P.

    2016-01-01

    ABSTRACT Ergosterol is a major and specific component of the fungal plasma membrane, and thus, the cytochrome P450 enzymes (Erg proteins) that catalyze ergosterol synthesis have been selected as valuable targets of azole antifungals. However, the opportunistic pathogen Aspergillus fumigatus has developed worldwide resistance to azoles largely through mutations in the cytochrome P450 enzyme Cyp51 (Erg11). In this study, we demonstrate that a cytochrome b5-like heme-binding damage resistance protein (Dap) family, comprised of DapA, DapB, and DapC, coordinately regulates the functionality of cytochrome P450 enzymes Erg5 and Erg11 and oppositely affects susceptibility to azoles. The expression of all three genes is induced in an azole concentration-dependent way, and the decreased susceptibility to azoles requires DapA stabilization of cytochrome P450 protein activity. In contrast, overexpression of DapB and DapC causes dysfunction of Erg5 and Erg11, resulting in abnormal accumulation of sterol intermediates and further accentuating the sensitivity of ΔdapA strains to azoles. The results of exogenous-hemin rescue and heme-binding-site mutagenesis experiments demonstrate that the heme binding of DapA contributes the decreased azole susceptibility, while DapB and -C are capable of reducing the activities of Erg5 and Erg11 through depletion of heme. In vivo data demonstrate that inactivated DapA combined with activated DapB yields an A. fumigatus mutant that is easily treatable with azoles in an immunocompromised mouse model of invasive pulmonary aspergillosis. Compared to the single Dap proteins found in Saccharomyces cerevisiae and Schizosaccharomyces pombe, we suggest that this complex Dap family regulatory system emerged during the evolution of fungi as an adaptive means to regulate ergosterol synthesis in response to environmental stimuli. PMID:26908577

  9. Gallium arsenide selectively up-regulates inflammatory cytokine expression at exposure site.

    PubMed

    Becker, Stephen M; McCoy, Kathleen L

    2003-12-01

    Gallium arsenide (GaAs), a technologically and economically important semiconductor, is widely utilized in both military and commercial applications. This chemical is a potential health hazard as a carcinogen and immunotoxicant. We previously reported that macrophages at the exposure site exhibit characteristics of activation. In vitro culture of macrophages with GaAs fails to recapitulate the in vivo phenotype, suggesting that complete GaAs-mediated activation in vivo may require other cells or components found in the body's microenvironment. Our present study examined the role of cytokines upon GaAs-mediated macrophage activation. Intraperitoneal administration of GaAs elicited rapid specific recruitment of blood monocytes to the exposure site. This recruitment occurred concomitant with up-regulation of 17 chemokine and inflammatory cytokine mRNAs, while transcripts of three inhibitory cytokines diminished. Administration of latex beads caused less cytokine induction than GaAs, indicating that changes in mRNA levels could not be attributed to phagocytosis. Four representative chemokines and cytokines were selected for further analysis. Increased cytokine mRNA expression was paralleled by similar increases in cytokine protein levels, and secreted protein products were detected in peritoneal fluid. Cytokine protein expression was constrained to myeloid cells, and to a lesser extent to B cells. Alterations in patterns of cytokine gene expression elucidate mechanisms for increased cellular activation and antigen processing, and modulation of the inflammatory response. Our findings indicate that in vivo GaAs exposure alters cytokine gene expression, which may lead to an inflammatory reaction and contribute to pathological tissue damage.

  10. Kinetics of nitric oxide dissociation from five- and six-coordinate nitrosyl hemes and heme proteins, including soluble guanylate cyclase.

    PubMed

    Kharitonov, V G; Sharma, V S; Magde, D; Koesling, D

    1997-06-01

    Kinetics of NO dissociation were characterized for three five-coordinate systems, heme-NO, HSA-heme-NO (human serum albumin), GC-NO (soluble guanylate cyclase), and for the six-coordinate system, Im-heme-NO. Nitrosyl myoglobin was redetermined for comparison. Previously known, six-coordinate R and T state nitrosyl hemoglobins are also included in the comparison. The data indicate that NO dissociates more than 1000 times faster from five-coordinate model heme than it does from the six-coordinate analog. Such a negative trans-effect between NO and a proximal base is in sharp contrast to carboxy heme derivatives, in which ligand dissociation rates are greatly slowed in when a trans base is present. As a result of opposite trans-effects, six-coordinate carboxy and nitrosyl derivatives have comparable dissociation rates, even though the five-coordinate species are very different. In proteins, five- and six-coordinate forms do not show a large difference in dissociation rates. Part of the reason may be due to different probabilities for geminate recombination in the different proteins, but this cannot explain all the facts. There must also be influences of the protein structure on bond-breaking rate constants themselves. With the exception of hemoglobin in the T state, nitrosyl guanylate cyclase shows the highest NO dissociation rate constant, k(obs) = 6 x 10(-4) s(-1). This would yield a half-life of about 2 min at 37 degrees C for dissociation of NO from GC-NO, a number that has implications for the mechanism of regulation of the activity of this key heme enzyme.

  11. Bovine herpesvirus type 1 (BHV-1) up-regulates telomerase activity in MDBK cells.

    PubMed

    Pagnini, U; De Martino, L; Montagnaro, S; Diodato, A; Longo, M; Pacelli, F; Pisanelli, G; Iovane, G

    2006-03-31

    The proliferative capacity of mammalian cells is regulated by telomerase, an enzyme uniquely specialised for telomeric DNA synthesis. The critical role of telomerase activation in tumor progression and maintenance has been well established in studies of cancer and of oncogenic transformation in cell culture. Experimental data suggest that telomerase activation has an important role in normal somatic cells, and that failure to activate sufficient telomerase also promotes disease. Evidence regarding the role of telomerase in the pathogenesis of several viruses including human immunodeficiency virus has led to an increased interest in the role of telomerase activity in other virus infections. In this research we evaluated the telomerase modulating activity of Bovine herpesvirus 1 (BHV-1) in MDBK cells. MDBK cells were infected at different multiplicity of infection with BHV-1 Cooper strain and telomerase activity at different times post-infection was measured by the TRAP assay. Our data indicate that BHV-1 significantly up-regulates telomerase activity at 3 and 6h post-infection decreasing after the 24h post-infection. Our data, showed that the effect was mediated by an immediate-early or early viral gene, and use of the protein translation inhibitor cycloheximide confirmed that an immediate early gene is primarily responsible.

  12. TNF-α contributes to up-regulation of Nav1.3 and Nav1.8 in DRG neurons following motor fiber injury.

    PubMed

    He, Xin-Hua; Zang, Ying; Chen, Xi; Pang, Rui-Ping; Xu, Ji-Tian; Zhou, Xiang; Wei, Xu-Hong; Li, Yong-Yong; Xin, Wen-Jun; Qin, Zhi-Hai; Liu, Xian-Guo

    2010-11-01

    A large body of evidence has demonstrated that the ectopic discharges of action potentials in primary afferents, resulted from the abnormal expression of voltage gated sodium channels (VGSCs) in dorsal root ganglion (DRG) neurons following peripheral nerve injury are important for the development of neuropathic pain. However, how nerve injury affects the expression of VGSCs is largely unknown. Here, we reported that selective injury of motor fibers by L5 ventral root transection (L5-VRT) up-regulated Nav1.3 and Nav1.8 at both mRNA and protein level and increased current densities of TTX-S and TTX-R channels in DRG neurons, suggesting that nerve injury may up-regulate functional VGSCs in sensory neurons indirectly. As the up-regulated Nav1.3 and Nav1.8 were highly co-localized with TNF-α, we tested the hypothesis that the increased TNF-α may lead to over-expression of the sodium channels. Indeed, we found that peri-sciatic administration of recombinant rat TNF-α (rrTNF) without any nerve injury, which produced lasting mechanical allodynia, also up-regulated Nav1.3 and Nav1.8 in DRG neurons in vivo and that rrTNF enhanced the expression of Nav1.3 and Nav1.8 in cultured adult rat DRG neurons in a dose-dependent manner. Furthermore, inhibition of TNF-α synthesis, which prevented neuropathic pain, strongly inhibited the up-regulation of Nav1.3 and Nav1.8. The up-regulation of the both channels following L5-VRT was significantly lower in TNF receptor 1 knockout mice than that in wild type mice. These data suggest that increased TNF-α may be responsible for up-regulation of Nav1.3 and Nav1.8 in uninjured DRG neurons following nerve injury. PMID:20638792

  13. Intrasplicing coordinates alternative first exons with alternative splicing in the protein 4.1R gene

    SciTech Connect

    Conboy, John G.; Parra, Marilyn K.; Tan, Jeff S.; Mohandas, Narla; Conboy, John G.

    2008-11-07

    In the protein 4.1R gene, alternative first exons splice differentially to alternative 3' splice sites far downstream in exon 2'/2 (E2'/2). We describe a novel intrasplicing mechanism by which exon 1A (E1A) splices exclusively to the distal E2'/2 acceptor via two nested splicing reactions regulated by novel properties of exon 1B (E1B). E1B behaves as an exon in the first step, using its consensus 5' donor to splice to the proximal E2'/2 acceptor. A long region of downstream intron is excised, juxtaposing E1B with E2'/2 to generate a new composite acceptor containing the E1B branchpoint/pyrimidine tract and E2 distal 3' AG-dinucleotide. Next, the upstream E1A splices over E1B to this distal acceptor, excising the remaining intron plus E1B and E2' to form mature E1A/E2 product. We mapped branch points for both intrasplicing reactions and demonstrated that mutation of the E1B 5' splice site or branchpoint abrogates intrasplicing. In the 4.1R gene, intrasplicing ultimately determines N-terminal protein structure and function. More generally, intrasplicing represents a new mechanism whereby alternative promoters can be coordinated with downstream alternative splicing.

  14. Stochastic but highly coordinated protein unfolding and translocation by the CIpXP proteolytic machine

    PubMed Central

    Cordova, Juan Carlos; Olivares, Adrian O.; Shin, Yongdae; Stinson, Benjamin M.; Calmat, Stephane; Schmitz, Karl R.; Aubin-Tam, Marie-Eve; Baker, Tania A.; Lang, Matthew J.; Sauer, Robert T.

    2014-01-01

    CIpXP and other AAA+ proteases recognize, mechanically unfold, and translocate target proteins into a chamber for proteolysis. It is not known if these remarkable molecular machines operate by a stochastic or sequential mechanism or how power strokes relate to the ATP-hydrolysis cycle. Single-molecule optical trapping allows CIpXP unfolding to be directly visualized and reveals translocation steps of ~1–4 nm in length, but how these activities relate to solution degradation and the physical properties of substrate proteins remains unclear. By studying single-molecule degradation using different multi-domain substrates and CIpXP variants, we answer many of these questions and provide evidence for stochastic unfolding and translocation. We also present a mechanochemical model that accounts for single-molecule, biochemical, and structural results, for our observation of enzymatic memory in translocation stepping, for the kinetics of translocation steps of different sizes, and for probabilistic but highly coordinated subunit activity within the CIpX ring. PMID:25083874

  15. Coordination of platinum therapeutic agents to met-rich motifs of human copper transport protein1.

    PubMed

    Crider, Sarah E; Holbrook, Robert J; Franz, Katherine J

    2010-01-01

    Platinum therapeutic agents are widely used in the treatment of several forms of cancer. Various mechanisms for the transport of the drugs have been proposed including passive diffusion across the cellular membrane and active transport via proteins. The copper transport protein Ctr1 is responsible for high affinity copper uptake but has also been implicated in the transport of cisplatin into cells. Human hCtr1 contains two methionine-rich Mets motifs on its extracellular N-terminus that are potential platinum-binding sites: the first one encompasses residues 7-14 with amino acid sequence Met-Gly-Met-Ser-Tyr-Met-Asp-Ser and the second one spans residues 39-46 with sequence Met-Met-Met-Met-Pro-Met-Thr-Phe. In these studies, we use liquid chromatography and mass spectrometry to compare the binding interactions between cisplatin, carboplatin and oxaliplatin with synthetic peptides corresponding to hCtr1 Mets motifs. The interactions of cisplatin and carboplatin with Met-rich motifs that contain three or more methionines result in removal of the carrier ligands of both platinum complexes. In contrast, oxaliplatin retains its cyclohexyldiamine ligand upon platinum coordination to the peptide.

  16. Nitrogen mustard up-regulates Bcl-2 and GSH and increases NTP and PCr in HT-29 colon cancer cells.

    PubMed Central

    Boddie, A. W.; Constantinou, A.; Williams, C.; Reed, A.

    1998-01-01

    We hypothesized that unexplained increases in nucleoside triphosphates (NTP) observed by 31P magnetic resonance spectroscopy (MRS) after treatment of tumours by DNA-damaging agents were related to chemotherapy-induced up-regulation of the bcl-2 gene and DNA damage prevention and repair processes. To test this hypothesis, we treated HT-29 cells with 10(-4) M nitrogen mustard (HN2) and performed sequential perchloric acid extractions in replicate over 0-18 h. By reference to an internal standard (methylene diphosphonic acid), absolute changes in 31P-detectable high-energy phosphates in these extracts were determined and correlated with changes in bcl-2 protein levels, cell viability, cell cycle, apoptosis and total cellular glutathione (GSH) (an important defence against DNA damage from alkylating agents). After HN2 administration, bcl-2 protein levels in the HT-29 cell line rose at 2 h. Cell viability declined to 25% within 18 h, but apoptosis measured using fluorescence techniques remained in the 1-4% range. Increased cell division was noted at 4 h. Two high-energy interconvertible phosphates, NTP (P < or = 0.006) and phosphocreatine (PCr) (P < or = 0.0002), increased at 2 h concurrently with increased levels of bcl-2 protein and glutathione. This study demonstrates that bcl-2 and glutathione are up-regulated by HN2 and links this to a previously unexplained 31P MRS phenomenon: increased NTP after chemotherapy. Images Figure 6 PMID:9652754

  17. Novel role of neuronal Ca2+ sensor-1 as a survival factor up-regulated in injured neurons.

    PubMed

    Nakamura, Tomoe Y; Jeromin, Andreas; Smith, George; Kurushima, Hideaki; Koga, Hitoshi; Nakabeppu, Yusaku; Wakabayashi, Shigeo; Nabekura, Junichi

    2006-03-27

    A molecular basis of survival from neuronal injury is essential for the development of therapeutic strategy to remedy neurodegenerative disorders. In this study, we demonstrate that an EF-hand Ca2+-binding protein neuronal Ca2+ sensor-1 (NCS-1), one of the key proteins for various neuronal functions, also acts as an important survival factor. Overexpression of NCS-1 rendered cultured neurons more tolerant to cell death caused by several kinds of stressors, whereas the dominant-negative mutant (E120Q) accelerated it. In addition, NCS-1 proteins increased upon treatment with glial cell line-derived neurotrophic factor (GDNF) and mediated GDNF survival signal in an Akt (but not MAPK)-dependent manner. Furthermore, NCS-1 is significantly up-regulated in response to axotomy-induced injury in the dorsal motor nucleus of the vagus neurons of adult rats in vivo, and adenoviral overexpression of E120Q resulted in a significant loss of surviving neurons, suggesting that NCS-1 is involved in an antiapoptotic mechanism in adult motor neurons. We propose that NCS-1 is a novel survival-promoting factor up-regulated in injured neurons that mediates the GDNF survival signal via the phosphatidylinositol 3-kinase-Akt pathway.

  18. TGF-β1 Up-Regulates Connective Tissue Growth Factor Expression in Human Granulosa Cells through Smad and ERK1/2 Signaling Pathways

    PubMed Central

    Cheng, Jung-Chien; Chang, Hsun-Ming; Fang, Lanlan; Sun, Ying-Pu; Leung, Peter C. K.

    2015-01-01

    Connective tissue growth factor (CTGF), which is also called CCN2, is a secreted matricellular protein. CTGF regulates various important cellular functions by interacting with multiple molecules in the microenvironment. In the ovary, CTGF is mainly expressed in granulosa cells and involved in the regulation of follicular development, ovulation and luteinization. TGF-β1 has been shown to up-regulate CTGF expression in rat and hen granulosa cells. However, the underlying molecular mechanisms of this up-regulation remain undefined. More importantly, whether the stimulatory effect of TGF-β1 on CTGF expression can be observed in human granulosa cells remains unknown. In the present study, our results demonstrated that TGF-β1 treatment up-regulates CTGF expression in both immortalized human granulosa cells and primary human granulosa cells. Using a siRNA-mediated knockdown approach and a pharmacological inhibitor, we demonstrated that the inhibition of Smad2, Smad3 or ERK1/2 attenuates the TGF-β1-induced up-regulation of CTGF. This study provides important insights into the molecular mechanisms that mediate TGF-β1-up-regulated CTGF expression in human granulosa cells. PMID:25955392

  19. TGF-β1 Up-Regulates Connective Tissue Growth Factor Expression in Human Granulosa Cells through Smad and ERK1/2 Signaling Pathways.

    PubMed

    Cheng, Jung-Chien; Chang, Hsun-Ming; Fang, Lanlan; Sun, Ying-Pu; Leung, Peter C K

    2015-01-01

    Connective tissue growth factor (CTGF), which is also called CCN2, is a secreted matricellular protein. CTGF regulates various important cellular functions by interacting with multiple molecules in the microenvironment. In the ovary, CTGF is mainly expressed in granulosa cells and involved in the regulation of follicular development, ovulation and luteinization. TGF-β1 has been shown to up-regulate CTGF expression in rat and hen granulosa cells. However, the underlying molecular mechanisms of this up-regulation remain undefined. More importantly, whether the stimulatory effect of TGF-β1 on CTGF expression can be observed in human granulosa cells remains unknown. In the present study, our results demonstrated that TGF-β1 treatment up-regulates CTGF expression in both immortalized human granulosa cells and primary human granulosa cells. Using a siRNA-mediated knockdown approach and a pharmacological inhibitor, we demonstrated that the inhibition of Smad2, Smad3 or ERK1/2 attenuates the TGF-β1-induced up-regulation of CTGF. This study provides important insights into the molecular mechanisms that mediate TGF-β1-up-regulated CTGF expression in human granulosa cells.

  20. Up-regulation of niacinamide in intervertebral disc aggrecan in vitro.

    PubMed

    Xiong, Xiaoqian; Yang, Shuhua; Shao, Zengwu; Liu, Xin; Zhan, Zirui; Duan, Deyu

    2006-01-01

    The regulatory effects of niacinamide (Nia) on intervertebral disc (IVD) aggrecan in vitro was investigated. Chiba's 10 ng/mL interleukin-1 (IL-1)-induced rabbit IVD degeneration model in vitro was established. 0.5, 0.25 and 0.05 mg/mL Nia was added to normal and degenerated IVDs for intervention. On the first and second week after intervention, safranin O-fast green staining intensity and glycosaminoglycan (GS) content were measured. The expression of aggrecan core protein was detected by RT-PCR. The results showed: (1) After treatment with 0.5 mg/mL Nia for one week, the GS content in nucleus pulposus (NP) was increased by 44.8% as compared with control group (P < 0 01); The GS content in IL-1 induction groups was increased with the increase of Nia concentrations: After treatment with 0.5 mg/mL for one week, the GS content in NP was increased by 68.3% as compared with control group (P < 0.01). After two weeks, GS content in NP and fibrous rings was still higher than in control group at the same period (P < 0.01) and untreated group (P < 0.01). (2) Safranin O-fast green staining revealed that with the increase of Nia concentrations, staining density in NP and fibrous rings was increased and histological structure damage to IVDs by IL-1beta was alleviated. (3) RT-PCR showed that the expression of core protein gene in IL-1beta-induced degenerated IVDS was increased with the increase of Nia concentrations. It was concluded that under conditions in vitro, Nia could up-regulate the expression of aggrecan in IVDs and protect IVDs from IL-1beta-induced degeneration at least partially, which offers a potential choice for IVD degeneration clinical therapy.

  1. Cathepsin D is up-regulated in inflammatory bowel disease macrophages

    PubMed Central

    HAUSMANN, M; OBERMEIER, F; SCHREITER, K; SPOTTL, T; FALK, W; SCHÖLMERICH, J; HERFARTH, H; SAFTIG, P; ROGLER, G

    2004-01-01

    Down-regulation of receptors involved in the recognition or transmission of inflammatory signals and a reduced responsiveness support the concept that macrophages are ‘desensitized’ during their differentiation in the intestinal mucosa. During inflammatory bowel disease (IBD) intestinal macrophages (IMACs) change to a reactive or ‘aggressive’ type. After having established a method of isolation and purification of IMACs, message for cathepsin D was one of the mRNAs we found to be up-regulated in a subtractive hybridization of Crohn's disease (CD) macrophages versus IMACs from control mucosa. The expression of cathepsin D in intestinal mucosa was analysed by immunohistochemistry in biopsies from IBD and control patients and in a mouse model of dextran sulphate sodium (DSS)-induced acute and chronic colitis. IMACs were isolated and purified from normal and inflamed mucosa by immunomagnetic beads armed with a CD33 antibody. RT-PCR was performed for cathepsin D mRNA. Results were confirmed by Northern blot and flow cytometrical analysis. Immunohistochemistry revealed a significant increase in the cathepsin D protein expression in inflamed intestinal mucosa from IBD patients compared to non-inflamed mucosa. No cathepsin D polymerase chain reaction (PCR) product could be obtained with mRNA from CD33-positive IMACs from normal mucosa. Reverse transcription (RT)-PCR showed an induction of mRNA for cathepsin D in purified IMACs from IBD patients. Northern blot and flow cytometry analysis confirmed these results. Cathepsin D protein was also found in intestinal mucosa in acute and chronic DSS-colitis but was absent in normal mucosa. This study shows that expression of cathepsin D is induced in inflammation-associated IMACs. The presence of cathepsin D might contribute to the mucosal damage in IBD. PMID:15030527

  2. Activation of neurokinin-1 receptors up-regulates substance P and neurokinin-1 receptor expression in murine pancreatic acinar cells.

    PubMed

    Koh, Yung-Hua; Moochhala, Shabbir; Bhatia, Madhav

    2012-07-01

    Acute pancreatitis (AP) has been associated with an up-regulation of substance P (SP) and neurokinin-1 receptor (NK1R) in the pancreas. Increased SP-NK1R interaction was suggested to be pro-inflammatory during AP. Previously, we showed that caerulein treatment increased SP/NK1R expression in mouse pancreatic acinar cells, but the effect of SP treatment was not evaluated. Pancreatic acinar cells were obtained from pancreas of male swiss mice (25-30 g). We measured mRNA expression of preprotachykinin-A (PPTA) and NK1R following treatment of SP (10(-6) M). SP treatment increased PPTA and NK1R expression in isolated pancreatic acinar cells, which was abolished by pretreatment of a selective NK1R antagonist, CP96,345. SP also time dependently increased protein expression of NK1R. Treatment of cells with a specific NK1R agonist, GR73,632, up-regulated SP protein levels in the cells. Using previously established concentrations, pre-treatment of pancreatic acinar cells with Gö6976 (10 nM), rottlerin (5 μM), PD98059 (30 μM), SP600125 (30 μM) or Bay11-7082 (30 μM) significantly inhibited up-regulation of SP and NK1R. These observations suggested that the PKC-ERK/JNK-NF-κB pathway is necessary for the modulation of expression levels. In comparison, pre-treatment of CP96,345 reversed gene expression in SP-induced cells, but not in caerulein-treated cells. Overall, the findings in this study suggested a possible auto-regulatory mechanism of SP/NK1R expression in mouse pancreatic acinar cells, via activation of NK1R. Elevated SP levels during AP might increase the occurrence of a positive feedback loop that contributes to abnormally high expression of SP and NK1R.

  3. Mitochondrial genes for heme-dependent respiratory chain complexes are up-regulated after depletion of Wolbachia from filarial nematodes.

    PubMed

    Strübing, Uta; Lucius, Richard; Hoerauf, Achim; Pfarr, Kenneth M

    2010-08-15

    The filarial nematodes Brugia malayi, Wuchereria bancrofti and Onchocerca volvulus cause elephantiasis or dermatitis and blindness resulting in severe morbidity. Annually, 1.3 billion people are at risk of infection. Targeting the essential Wolbachia endobacteria of filarial nematodes with doxycycline has proven to be an effective therapy resulting in a block in embryogenesis, worm development and macrofilaricidal effects. However, doxycycline is contraindicated for a large portion of the at risk population. To identify new targets for anti-wolbachial therapy, understanding the molecular basis of the Wolbachia-filaria symbiosis is required. Using the B. malayi microarray we identified differentially expressed genes in the rodent filaria Litomosoides sigmodontis after depletion of Wolbachia which might have a role in symbiosis. The microarray data were filtered for regulated genes with a false discovery rate <5% and a > or = 2-fold-change. Most of the genes were differentially expressed at day 36 of tetracycline treatment, when 99.8% of Wolbachia were depleted. Several classes of genes were affected, including genes for translation, transcription, folding/sorting of proteins, motility, structure and metabolic and signalling pathways. Quantitative PCR validated 60% of the genes found to be regulated in the microarray. A nuclear encoded heme-binding protein of the globin family was up-regulated upon loss of Wolbachia. Interestingly, mitochondrial encoded subunits of respiratory chain complexes containing heme and riboflavin were also up-regulated. No change in the expression of these genes was seen in tetracycline treated Wolbachia-free Acanthocheilonema viteae. As Wolbachia synthesise heme and filaria do not, we hypothesise that without the endosymbionts no functional heme-containing enzymes can be formed, leading to loss of energy metabolism which then results in up-regulation of the mitochondrial encoded subunits in an attempt to correct the deviation from

  4. Signal pathways in up-regulation of chemokines by tyrosine kinase MER/NYK in prostate cancer cells.

    PubMed

    Wu, Yi-Mi; Robinson, Dan R; Kung, Hsing-Jien

    2004-10-15

    The AXL/UFO family of tyrosine kinases is characterized by a common N-CAM (neural adhesion molecule)-related extracellular domain and a common ligand, GAS6 (growth arrest-specific protein 6). Family members are prone to transcriptional regulation and carry out diverse functions including the regulation of cell adhesion, migration, phagocytosis, and survival. In this report, we describe a new role of MER/N-CAM-related kinase (NYK), a member of the AXL family of kinases, in the up-regulation of chemokines in prostate cancer cells. We show that NYK has elevated expression in a subset of tumor specimens and prostate cancer cell lines. Activation of NYK in the prostate cancer cell line DU145 does not cause a mitogenic effect; instead, it causes a differentiation phenotype. Microarray analysis revealed that NYK is a strong inducer of endocrine factors including interleukin (IL)-8 and several other angiogenic CXC chemokines as well as bone morphogenic factors. The dramatic increase of IL-8 expression is seen at both transcriptional and posttranscriptional levels. The downstream signals engaged by NYK were characterized, and those responsible for the up-regulation of IL-8 transcription were defined. In contrast to IL-1alpha, NYK-induced up-regulation of IL-8 in DU145 depends on the mitogen-activated protein kinase kinase/extracellular signal-regulated kinase/Jun/Fos pathway, but not phosphoinositide 3'-kinase/nuclear factor-kappaB. These data define a new function of the AXL family of kinases and suggest a potential role of NYK in prostate cancer progression. PMID:15492251

  5. Hypoxia Suppresses Spontaneous Mineralization and Osteogenic Differentiation of Mesenchymal Stem Cells via IGFBP3 Up-Regulation

    PubMed Central

    Kim, Ji Hye; Yoon, Sei Mee; Song, Sun U.; Park, Sang Gyu; Kim, Won-Serk; Park, In Guk; Lee, Jinu; Sung, Jong-Hyuk

    2016-01-01

    Hypoxia has diverse stimulatory effects on human adipose-derived stem cells (ASCs). In the present study, we investigated whether hypoxic culture conditions (2% O2) suppress spontaneous mineralization and osteogenic differentiation of ASCs. We also investigated signaling pathways and molecular mechanisms involved in this process. We found that hypoxia suppressed spontaneous mineralization and osteogenic differentiation of ASCs, and up-regulated mRNA and protein expression of Insulin-like growth factor binding proteins (IGFBPs) in ASCs. Although treatment with recombinant IGFBPs did not affect osteogenic differentiation of ASCs, siRNA-mediated inhibition of IGFBP3 attenuated hypoxia-suppressed osteogenic differentiation of ASCs. In contrast, overexpression of IGFBP3 via lentiviral vectors inhibited ASC osteogenic differentiation. These results indicate that hypoxia suppresses spontaneous mineralization and osteogenic differentiation of ASCs via intracellular IGFBP3 up-regulation. We determined that reactive oxygen species (ROS) generation followed by activation of the MAPK and PI3K/Akt pathways play pivotal roles in IGFBP3 expression under hypoxia. For example, ROS scavengers and inhibitors for MAPK and PI3K/Akt pathways attenuated the hypoxia-induced IGFBP3 expression. Inhibition of Elk1 and NF-κB through siRNA transfection also led to down-regulation of IGFBP3 mRNA expression. We next addressed the proliferative potential of ASCs with overexpressed IGFBP3, but IGFBP3 overexpression reduced the proliferation of ASCs. In addition, hypoxia reduced the osteogenic differentiation of bone marrow-derived clonal mesenchymal stem cells. Collectively, our results indicate that hypoxia suppresses the osteogenic differentiation of mesenchymal stem cells via IGFBP3 up-regulation. PMID:27563882

  6. Activation of neurokinin-1 receptors up-regulates substance P and neurokinin-1 receptor expression in murine pancreatic acinar cells

    PubMed Central

    Koh, Yung-Hua; Moochhala, Shabbir; Bhatia, Madhav

    2012-01-01

    Abstract Acute pancreatitis (AP) has been associated with an up-regulation of substance P (SP) and neurokinin-1 receptor (NK1R) in the pancreas. Increased SP-NK1R interaction was suggested to be pro-inflammatory during AP. Previously, we showed that caerulein treatment increased SP/NK1R expression in mouse pancreatic acinar cells, but the effect of SP treatment was not evaluated. Pancreatic acinar cells were obtained from pancreas of male swiss mice (25–30 g). We measured mRNA expression of preprotachykinin-A (PPTA) and NK1R following treatment of SP (10−6M). SP treatment increased PPTA and NK1R expression in isolated pancreatic acinar cells, which was abolished by pretreatment of a selective NK1R antagonist, CP96,345. SP also time dependently increased protein expression of NK1R. Treatment of cells with a specific NK1R agonist, GR73,632, up-regulated SP protein levels in the cells. Using previously established concentrations, pre-treatment of pancreatic acinar cells with Gö6976 (10 nM), rottlerin (5 μM), PD98059 (30 μM), SP600125 (30 μM) or Bay11-7082 (30 μM) significantly inhibited up-regulation of SP and NK1R. These observations suggested that the PKC-ERK/JNK-NF-κB pathway is necessary for the modulation of expression levels. In comparison, pre-treatment of CP96,345 reversed gene expression in SP-induced cells, but not in caerulein-treated cells. Overall, the findings in this study suggested a possible auto-regulatory mechanism of SP/NK1R expression in mouse pancreatic acinar cells, via activation of NK1R. Elevated SP levels during AP might increase the occurrence of a positive feedback loop that contributes to abnormally high expression of SP and NK1R. PMID:22040127

  7. 3'5'-cyclic adenosine monophosphate-dependent up-regulation of phosphodiesterase type 3A in porcine cumulus cells.

    PubMed

    Sasseville, Maxime; Côté, Nancy; Vigneault, Christian; Guillemette, Christine; Richard, François J

    2007-04-01

    The means by which cumulus cells react to gonadotropin stimulation and regulate the subsequent production and degradation of cAMP are largely unknown. In this article, we report that cyclic nucleotide phosphodiesterase (PDE) type 3A (Pde3a) is transcriptionally regulated in porcine cumulus cells by a cAMP-dependent pathway during in vitro maturation (IVM). cAMP-PDE activity was increased in the cumulus-oocyte complex (COC) after 10 h of IVM, and 78% of this increase was sensitive to a Pde3-specific inhibitor, cilostamide. Although no variation was observed in the oocyte, cilostamide-sensitive cAMP-PDE activity increased in the cumulus cells after IVM. This was supported by Western blotting, which showed that the intensity of a 135-kDa anti-Pde3a immunoreactive band was increased in COC after IVM. The Pde3a mRNA level was up-regulated 28-fold in the COC after 4 h of IVM and remained high up to 12 h. The mRNA up-regulation and increased activity were inhibited by an RNA synthesis inhibitor, alpha-amanitin. The cilostamide-sensitive increase in PDE activity was inhibited by a protein synthesis inhibitor, cycloheximide. Pregnant mare serum gonadotropin (PMSG) caused dose-dependent activation of Pde3. The PMSG-dependent increase in Pde3 activity and Pde3a mRNA were mimicked by the adenylyl cyclase activator forskolin or prostaglandin E2. PMSG-dependent Pde3 activation was inhibited by the protein kinase A-specific inhibitor H89. Collectively, our results show for the first time that degradation of the intracellular cyclic nucleotide by Pde3a is transcriptionally up-regulated via a cAMP-dependent pathway in cumulus cells, suggesting that it has a functional role during the ovulatory gonadotropin surge.

  8. Hypoxia Suppresses Spontaneous Mineralization and Osteogenic Differentiation of Mesenchymal Stem Cells via IGFBP3 Up-Regulation.

    PubMed

    Kim, Ji Hye; Yoon, Sei Mee; Song, Sun U; Park, Sang Gyu; Kim, Won-Serk; Park, In Guk; Lee, Jinu; Sung, Jong-Hyuk

    2016-01-01

    Hypoxia has diverse stimulatory effects on human adipose-derived stem cells (ASCs). In the present study, we investigated whether hypoxic culture conditions (2% O₂) suppress spontaneous mineralization and osteogenic differentiation of ASCs. We also investigated signaling pathways and molecular mechanisms involved in this process. We found that hypoxia suppressed spontaneous mineralization and osteogenic differentiation of ASCs, and up-regulated mRNA and protein expression of Insulin-like growth factor binding proteins (IGFBPs) in ASCs. Although treatment with recombinant IGFBPs did not affect osteogenic differentiation of ASCs, siRNA-mediated inhibition of IGFBP3 attenuated hypoxia-suppressed osteogenic differentiation of ASCs. In contrast, overexpression of IGFBP3 via lentiviral vectors inhibited ASC osteogenic differentiation. These results indicate that hypoxia suppresses spontaneous mineralization and osteogenic differentiation of ASCs via intracellular IGFBP3 up-regulation. We determined that reactive oxygen species (ROS) generation followed by activation of the MAPK and PI3K/Akt pathways play pivotal roles in IGFBP3 expression under hypoxia. For example, ROS scavengers and inhibitors for MAPK and PI3K/Akt pathways attenuated the hypoxia-induced IGFBP3 expression. Inhibition of Elk1 and NF-κB through siRNA transfection also led to down-regulation of IGFBP3 mRNA expression. We next addressed the proliferative potential of ASCs with overexpressed IGFBP3, but IGFBP3 overexpression reduced the proliferation of ASCs. In addition, hypoxia reduced the osteogenic differentiation of bone marrow-derived clonal mesenchymal stem cells. Collectively, our results indicate that hypoxia suppresses the osteogenic differentiation of mesenchymal stem cells via IGFBP3 up-regulation. PMID:27563882

  9. Ischemia-Reperfusion Injury and Pregnancy Initiate Time-Dependent and Robust Signs of Up-Regulation of Cardiac Progenitor Cells

    PubMed Central

    Genead, Rami; Fischer, Helene; Hussain, Alamdar; Jaksch, Marie; Andersson, Agneta B.; Ljung, Karin; Bulatovic, Ivana; Franco-Cereceda, Anders; Elsheikh, Elzafir; Corbascio, Matthias; Smith, C. I. Edvard; Sylvén, Christer; Grinnemo, Karl-Henrik

    2012-01-01

    To explore how cardiac regeneration and cell turnover adapts to disease, different forms of stress were studied for their effects on the cardiac progenitor cell markers c-Kit and Isl1, the early cardiomyocyte marker Nkx2.5, and mast cells. Adult female rats were examined during pregnancy, after myocardial infarction and ischemia-reperfusion injury with/out insulin like growth factor-1(IGF-1) and hepatocyte growth factor (HGF). Different cardiac sub-domains were analyzed at one and two weeks post-intervention, both at the mRNA and protein levels. While pregnancy and myocardial infarction up-regulated Nkx2.5 and c-Kit (adjusted for mast cell activation), ischemia-reperfusion injury induced the strongest up-regulation which occurred globally throughout the entire heart and not just around the site of injury. This response seems to be partly mediated by increased endogenous production of IGF-1 and HGF. Contrary to c-Kit, Isl1 was not up-regulated by pregnancy or myocardial infarction while ischemia-reperfusion injury induced not a global but a focal up-regulation in the outflow tract and also in the peri-ischemic region, correlating with the up-regulation of endogenous IGF-1. The addition of IGF-1 and HGF did boost the endogenous expression of IGF and HGF correlating to focal up-regulation of Isl1. c-Kit expression was not further influenced by the exogenous growth factors. This indicates that there is a spatial mismatch between on one hand c-Kit and Nkx2.5 expression and on the other hand Isl1 expression. In conclusion, ischemia-reperfusion injury was the strongest stimulus with both global and focal cardiomyocyte progenitor cell marker up-regulations, correlating to the endogenous up-regulation of the growth factors IGF-1 and HGF. Also pregnancy induced a general up-regulation of c-Kit and early Nkx2.5+ cardiomyocytes throughout the heart. Utilization of these pathways could provide new strategies for the treatment of cardiac disease. PMID:22590612

  10. Axotomy does not up-regulate expression of sodium channel Na(v)1.8 in Purkinje cells.

    PubMed

    Black, J A; Dusart, I; Sotelo, C; Waxman, S G

    2002-05-30

    Aberrant expression of the sensory neuron specific (SNS) sodium channel Na(v)1.8 has been demonstrated in cerebellar Purkinje cells in experimental models of multiple sclerosis (MS) and in human MS. The aberrant expression of Na(v)1.8, which is normally present in primary sensory neurons but not in the CNS, may perturb cerebellar function, but the mechanisms that trigger it are not understood. Because axotomy can provoke changes in Na(v)1.8 expression in dorsal root ganglion (DRG) neurons, we tested the hypothesis that axotomy can provoke an up-regulation of Na(v)1.8 expression in Purkinje cells, using a surgical model that transects axons of Purkinje cells in lobules IIIb-VII in the rat. In situ hybridization and immunocytochemistry did not reveal an up-regulation of Na(v)1.8 mRNA or protein in axotomized Purkinje cells. Hybridization and immunostaining signals for the sodium channel Na(v)1.6 were clearly present, demonstrating that sodium channel transcripts and protein were present in experimental cerebella. These results demonstrate that axotomy does not trigger the expression of Na(v)1.8 in Purkinje cells. PMID:12007840

  11. Up-regulation of alpha1-microglobulin by hemoglobin and reactive oxygen species in hepatoma and blood cell lines.

    PubMed

    Olsson, Magnus G; Allhorn, Maria; Olofsson, Tor; Akerström, Bo

    2007-03-15

    alpha(1)-Microglobulin is a 26-kDa glycoprotein synthesized in the liver, secreted to the blood, and rapidly distributed to the extravascular compartment of all tissues. Recent results show that alpha(1)-microglobulin has heme-binding and heme-degrading properties and it has been suggested that the protein is involved in the defense against oxidation by heme and reactive oxygen species. In the present study the influence of hemoglobin and reactive oxygen species (ROS) on the cellular expression of alpha(1)-microglobulin was investigated. Oxy- and methemoglobin, free heme, and Fenton reaction-induced hydroxyl radicals induced a dose-dependent up-regulation of alpha(1)-microglobulin on both mRNA and protein levels in hepatoma cells and an increased secretion of alpha(1)-microglobulin. The up-regulation was reversed by the addition of catalase and ascorbate, and by reacting hemoglobin with cyanide which prevents redox reactions. Furthermore, the blood cell lines U937 and K562 expressed alpha(1)-microglobulin at low levels, and this expression increased up to 11-fold by the addition of hemoglobin. These results suggest that alpha(1)-microglobulin expression is induced by ROS, arising from redox reactions of hemoglobin or from other sources and are consistent with the hypothesis that alpha(1)-microglobulin participates in the defense against oxidation by hemoglobin, heme, and reactive oxygen species.

  12. Coordinated Regulation of Vasopressin Inactivation and Glucose Uptake by Action of TUG Protein in Muscle*

    PubMed Central

    Habtemichael, Estifanos N.; Alcázar-Román, Abel; Rubin, Bradley R.; Grossi, Laura R.; Belman, Jonathan P.; Julca, Omar; Löffler, Michael G.; Li, Hongjie; Chi, Nai-Wen; Samuel, Varman T.; Bogan, Jonathan S.

    2015-01-01

    In adipose and muscle cells, insulin stimulates the exocytic translocation of vesicles containing GLUT4, a glucose transporter, and insulin-regulated aminopeptidase (IRAP), a transmembrane aminopeptidase. A substrate of IRAP is vasopressin, which controls water homeostasis. The physiological importance of IRAP translocation to inactivate vasopressin remains uncertain. We previously showed that in skeletal muscle, insulin stimulates proteolytic processing of the GLUT4 retention protein, TUG, to promote GLUT4 translocation and glucose uptake. Here we show that TUG proteolysis also controls IRAP targeting and regulates vasopressin action in vivo. Transgenic mice with constitutive TUG proteolysis in muscle consumed much more water than wild-type control mice. The transgenic mice lost more body weight during water restriction, and the abundance of renal AQP2 water channels was reduced, implying that vasopressin activity is decreased. To compensate for accelerated vasopressin degradation, vasopressin secretion was increased, as assessed by the cosecreted protein copeptin. IRAP abundance was increased in T-tubule fractions of fasting transgenic mice, when compared with controls. Recombinant IRAP bound to TUG, and this interaction was mapped to a short peptide in IRAP that was previously shown to be critical for GLUT4 intracellular retention. In cultured 3T3-L1 adipocytes, IRAP was present in TUG-bound membranes and was released by insulin stimulation. Together with previous results, these data support a model in which TUG controls vesicle translocation by interacting with IRAP as well as GLUT4. Furthermore, the effect of IRAP to reduce vasopressin activity is a physiologically important consequence of vesicle translocation, which is coordinated with the stimulation of glucose uptake. PMID:25944897

  13. Methamphetamine acutely inhibits voltage-gated calcium channels but chronically up-regulates L-type channels.

    PubMed

    Andres, Marilou A; Cooke, Ian M; Bellinger, Frederick P; Berry, Marla J; Zaporteza, Maribel M; Rueli, Rachel H; Barayuga, Stephanie M; Chang, Linda

    2015-07-01

    In neurons, calcium (Ca(2+) ) channels regulate a wide variety of functions ranging from synaptic transmission to gene expression. They also induce neuroplastic changes that alter gene expression following psychostimulant administration. Ca(2+) channel blockers have been considered as potential therapeutic agents for the treatment of methamphetamine (METH) dependence because of their ability to reduce drug craving among METH users. Here, we studied the effects of METH exposure on voltage-gated Ca(2+) channels using SH-SY5Y cells as a model of dopaminergic neurons. We found that METH has different short- and long-term effects. A short-term effect involves immediate (< 5 min) direct inhibition of Ca(2+) ion movements through Ca(2+) channels. Longer exposure to METH (20 min or 48 h) selectively up-regulates the expression of only the CACNA1C gene, thus increasing the number of L-type Ca(2+) channels. This up-regulation of CACNA1C is associated with the expression of the cAMP-responsive element-binding protein (CREB), a known regulator of CACNA1C gene expression, and the MYC gene, which encodes a transcription factor that putatively binds to a site proximal to the CACNA1C gene transcription initiation site. The short-term inhibition of Ca(2+) ion movement and later, the up-regulation of Ca(2+) channel gene expression together suggest the operation of cAMP-responsive element-binding protein- and C-MYC-mediated mechanisms to compensate for Ca(2+) channel inhibition by METH. Increased Ca(2+) current density and subsequent increased intracellular Ca(2+) may contribute to the neurodegeneration accompanying chronic METH abuse. Methamphetamine (METH) exposure has both short- and long-term effects. Acutely, methamphetamine directly inhibits voltage-gated calcium channels. Chronically, neurons compensate by up-regulating the L-type Ca(2+) channel gene, CACNA1C. This compensatory mechanism is mediated by transcription factors C-MYC and CREB, in which CREB is linked to the

  14. Coordinate control of terminal dendrite patterning and dynamics by the membrane protein Raw

    PubMed Central

    Lee, Jiae; Peng, Yun; Lin, Wen-Yang; Parrish, Jay Z.

    2015-01-01

    The directional flow of information in neurons depends on compartmentalization: dendrites receive inputs whereas axons transmit them. Axons and dendrites likewise contain structurally and functionally distinct subcompartments. Axon/dendrite compartmentalization can be attributed to neuronal polarization, but the developmental origin of subcompartments in axons and dendrites is less well understood. To identify the developmental bases for compartment-specific patterning in dendrites, we screened for mutations that affect discrete dendritic domains in Drosophila sensory neurons. From this screen, we identified mutations that affected distinct aspects of terminal dendrite development with little or no effect on major dendrite patterning. Mutation of one gene, raw, affected multiple aspects of terminal dendrite patterning, suggesting that Raw might coordinate multiple signaling pathways to shape terminal dendrite growth. Consistent with this notion, Raw localizes to branch-points and promotes dendrite stabilization together with the Tricornered (Trc) kinase via effects on cell adhesion. Raw independently influences terminal dendrite elongation through a mechanism that involves modulation of the cytoskeleton, and this pathway is likely to involve the RNA-binding protein Argonaute 1 (AGO1), as raw and AGO1 genetically interact to promote terminal dendrite growth but not adhesion. Thus, Raw defines a potential point of convergence in distinct pathways shaping terminal dendrite patterning. PMID:25480915

  15. The Wnt Inhibitor Sclerostin Is Up-regulated by Mechanical Unloading in Osteocytes in Vitro.

    PubMed

    Spatz, Jordan M; Wein, Marc N; Gooi, Jonathan H; Qu, Yili; Garr, Jenna L; Liu, Shawn; Barry, Kevin J; Uda, Yuhei; Lai, Forest; Dedic, Christopher; Balcells-Camps, Mercedes; Kronenberg, Henry M; Babij, Philip; Pajevic, Paola Divieti

    2015-07-01

    Although bone responds to its mechanical environment, the cellular and molecular mechanisms underlying the response of the skeleton to mechanical unloading are not completely understood. Osteocytes are the most abundant but least understood cells in bones and are thought to be responsible for sensing stresses and strains in bone. Sclerostin, a product of the SOST gene, is produced postnatally primarily by osteocytes and is a negative regulator of bone formation. Recent studies show that SOST is mechanically regulated at both the mRNA and protein levels. During prolonged bed rest and immobilization, circulating sclerostin increases both in humans and in animal models, and its increase is associated with a decrease in parathyroid hormone. To investigate whether SOST/sclerostin up-regulation in mechanical unloading is a cell-autonomous response or a hormonal response to decreased parathyroid hormone levels, we subjected osteocytes to an in vitro unloading environment achieved by the NASA rotating wall vessel system. To perform these studies, we generated a novel osteocytic cell line (Ocy454) that produces high levels of SOST/sclerostin at early time points and in the absence of differentiation factors. Importantly, these osteocytes recapitulated the in vivo response to mechanical unloading with increased expression of SOST (3.4 ± 1.9-fold, p < 0.001), sclerostin (4.7 ± 0.1-fold, p < 0.001), and the receptor activator of nuclear factor κΒ ligand (RANKL)/osteoprotegerin (OPG) (2.5 ± 0.7-fold, p < 0.001) ratio. These data demonstrate for the first time a cell-autonomous increase in SOST/sclerostin and RANKL/OPG ratio in the setting of unloading. Thus, targeted osteocyte therapies could hold promise as novel osteoporosis and disuse-induced bone loss treatments by directly modulating the mechanosensing cells in bone.

  16. Stat3 promotes invasion of esophageal squamous cell carcinoma through up-regulation of MMP2.

    PubMed

    Xuan, Xaioyan; Li, Shanshan; Lou, Xi; Zheng, Xianzhao; Li, Yunyun; Wang, Feng; Gao, Yuan; Zhang, Hongyan; He, Hongliu; Zeng, Qingru

    2015-05-01

    Stat3 alters the expression of its downstream genes and is associated with tumor invasion and metastasis in several human cancers. Its role in esophageal squamous cell carcinoma (ESCC) has not been well characterized. We examined the tumor sections of 100 cases of ESCC by immunohistochemistry and observed significant overexpression of Stat3 in the cytoplasm of 89% of ESCC cells and of phosphorylated Stat3 (p-Stat3) in the nuclei of 71% of ESCC when compare with normal esophageal mucosa (72%, p = 0.02; and 31%, p = 0.001). Overexpression of Stat3 and p-Stat3 positively correlated with that of matrix metalloproteinase-2 (MMP2), a known regulator for cell migration, in 65% of ESCC while only 26% shown in benign esophageal mucosa. To further investigate the association of Stat3 with tumor metastasis in vitro, invasion of EC-1 cells (a human ESCC cell line) were investigated with Boyden chambers. The results showed that transfection of Stat3 not only promoted invasion of EC-1 cells but also significantly induced MMP2 expression in a dose-dependent manner. In contrast, suppressing expression of endogenous Stat3 mRNA and protein by Stat3 siRNA significantly reduced EC-1 cell invasion and MMP2 expression. A high-affinity Stat3-binding element was localized to the positions of 648-641 bp (TTCTCGAA) in the MMP2 promoter with electrophoretic mobility shift assay. Our results suggest that Stat3, p-Stat3, and MMP2 were overexpressed in ESCC and associated with invasion of ESCC; and Stat3 up-regulated expression of MMP2 in ESCC through directly binding to the MMP2 promoter.

  17. Modified AS1411 Aptamer Suppresses Hepatocellular Carcinoma by Up-Regulating Galectin-14

    PubMed Central

    Lee, Jeong-Hoon; Lee, Dong Hyeon; Cho, Eun Ju; Yu, Su Jong; Kim, Yoon Jun; Kim, Jong In; Im, Jong Hun; Lee, Jung Hwan; Oh, Eun Ju; Yoon, Jung-Hwan

    2016-01-01

    Aptamers are small synthetic oligonucleotides that bind to target proteins with high specificity and affinity. AS1411 is an aptamer that binds to nucleolin, which is overexpressed in the cytoplasm and occurs on the surface of cancer cells. We investigated the therapeutic potential of aptamers in hepatocellular carcinoma (HCC) by evaluating anti-tumor effects and confirming the affinity and specificity of AS1411- and modified AS1411-aptamers in HCC cells. Cell growth was assessed using the MTS assay, and cell death signaling was explored by immunoblot analysis. Fluorescence-activated cell sorting was performed to evaluate the affinity and specificity of AS1411-aptamers in SNU-761 HCC cells. We investigated the in vivo effects of the AS1411-aptamer using BALB/c nude mice in a subcutaneous xenograft model with SNU-761 cells. Treatment with a modified AS1411-aptamer significantly decreased in vitro (under normoxic [P = 0.035] and hypoxic [P = 0.018] conditions) and in vivo (under normoxic conditions, P = 0.041) HCC cell proliferation compared to control aptamers. AS1411- and control aptamers failed to control HCC cell proliferation. However, AS1411- and the modified AS1411-aptamer did not induce caspase activation. Decrease in cell growth by AS1411 or modified AS1411 was not prevented by caspase or necrosis inhibitors. In a microarray, AS1411 significantly enhanced galectin-14 expression. Suppression of HCC cell proliferation by the modified AS1411-aptamer was attenuated by galectin-14 siRNA transfection. Modified AS1411-aptamer suppressed HCC cell growth in vitro and in vivo by up-regulating galectin-14 expressions. Modified AS1411-aptamers may have therapeutic potential as a novel targeted therapy for HCC. PMID:27494117

  18. The Wnt Inhibitor Sclerostin Is Up-regulated by Mechanical Unloading in Osteocytes in Vitro.

    PubMed

    Spatz, Jordan M; Wein, Marc N; Gooi, Jonathan H; Qu, Yili; Garr, Jenna L; Liu, Shawn; Barry, Kevin J; Uda, Yuhei; Lai, Forest; Dedic, Christopher; Balcells-Camps, Mercedes; Kronenberg, Henry M; Babij, Philip; Pajevic, Paola Divieti

    2015-07-01

    Although bone responds to its mechanical environment, the cellular and molecular mechanisms underlying the response of the skeleton to mechanical unloading are not completely understood. Osteocytes are the most abundant but least understood cells in bones and are thought to be responsible for sensing stresses and strains in bone. Sclerostin, a product of the SOST gene, is produced postnatally primarily by osteocytes and is a negative regulator of bone formation. Recent studies show that SOST is mechanically regulated at both the mRNA and protein levels. During prolonged bed rest and immobilization, circulating sclerostin increases both in humans and in animal models, and its increase is associated with a decrease in parathyroid hormone. To investigate whether SOST/sclerostin up-regulation in mechanical unloading is a cell-autonomous response or a hormonal response to decreased parathyroid hormone levels, we subjected osteocytes to an in vitro unloading environment achieved by the NASA rotating wall vessel system. To perform these studies, we generated a novel osteocytic cell line (Ocy454) that produces high levels of SOST/sclerostin at early time points and in the absence of differentiation factors. Importantly, these osteocytes recapitulated the in vivo response to mechanical unloading with increased expression of SOST (3.4 ± 1.9-fold, p < 0.001), sclerostin (4.7 ± 0.1-fold, p < 0.001), and the receptor activator of nuclear factor κΒ ligand (RANKL)/osteoprotegerin (OPG) (2.5 ± 0.7-fold, p < 0.001) ratio. These data demonstrate for the first time a cell-autonomous increase in SOST/sclerostin and RANKL/OPG ratio in the setting of unloading. Thus, targeted osteocyte therapies could hold promise as novel osteoporosis and disuse-induced bone loss treatments by directly modulating the mechanosensing cells in bone. PMID:25953900

  19. The Wnt Inhibitor Sclerostin Is Up-regulated by Mechanical Unloading in Osteocytes in Vitro*

    PubMed Central

    Spatz, Jordan M.; Wein, Marc N.; Gooi, Jonathan H.; Qu, Yili; Garr, Jenna L.; Liu, Shawn; Barry, Kevin J.; Uda, Yuhei; Lai, Forest; Dedic, Christopher; Balcells-Camps, Mercedes; Kronenberg, Henry M.; Babij, Philip; Pajevic, Paola Divieti

    2015-01-01

    Although bone responds to its mechanical environment, the cellular and molecular mechanisms underlying the response of the skeleton to mechanical unloading are not completely understood. Osteocytes are the most abundant but least understood cells in bones and are thought to be responsible for sensing stresses and strains in bone. Sclerostin, a product of the SOST gene, is produced postnatally primarily by osteocytes and is a negative regulator of bone formation. Recent studies show that SOST is mechanically regulated at both the mRNA and protein levels. During prolonged bed rest and immobilization, circulating sclerostin increases both in humans and in animal models, and its increase is associated with a decrease in parathyroid hormone. To investigate whether SOST/sclerostin up-regulation in mechanical unloading is a cell-autonomous response or a hormonal response to decreased parathyroid hormone levels, we subjected osteocytes to an in vitro unloading environment achieved by the NASA rotating wall vessel system. To perform these studies, we generated a novel osteocytic cell line (Ocy454) that produces high levels of SOST/sclerostin at early time points and in the absence of differentiation factors. Importantly, these osteocytes recapitulated the in vivo response to mechanical unloading with increased expression of SOST (3.4 ± 1.9-fold, p < 0.001), sclerostin (4.7 ± 0.1-fold, p < 0.001), and the receptor activator of nuclear factor κΒ ligand (RANKL)/osteoprotegerin (OPG) (2.5 ± 0.7-fold, p < 0.001) ratio. These data demonstrate for the first time a cell-autonomous increase in SOST/sclerostin and RANKL/OPG ratio in the setting of unloading. Thus, targeted osteocyte therapies could hold promise as novel osteoporosis and disuse-induced bone loss treatments by directly modulating the mechanosensing cells in bone. PMID:25953900

  20. Up-regulation of hypoxia-inducible factor-1α enhanced the cardioprotective effects of ischemic postconditioning in hyperlipidemic rats.

    PubMed

    Li, Xiaoyu; Zhao, Huanxin; Wu, Ye; Zhang, Suli; Zhao, Xiaoqin; Zhang, Yan; Wang, Jin; Wang, Jie; Liu, Huirong

    2014-02-01

    Hyperlipidemia is an independent risk factor in the development of ischemic heart disease, which can increase myocardial susceptibility to ischemia/reperfusion (I/R) injury. Ischemic postconditioning (PostC) has now been demonstrated as a novel strategy to harness nature's protection against myocardial I/R injury in normal conditions. However, the effect of PostC on hyperlipidemic animals remains elusive. It has been shown in our previous study that PostC reduces the myocardial I/R injury, and hypoxia-inducible factor-1α (HIF-1α) may play an important role in the cardioprotective mechanisms of PostC on normal rats. Here, we tested the hypothesis that the cardioprotection of PostC on hyperlipidemic rats is associated with the up-regulated HIF-1α expression. Male Wistar rats were fed with a high-fat diet for 8 weeks, and then randomly divided into five groups: sham, I/R, dimethyloxalylglycine (DMOG) + I/R, PostC, and DMOG + PostC group. The detrimental indices induced by I/R injury included infarct size, plasma creatine kinase (CK) activity and caspase-3 activity. The results showed that PostC could reduce the infarct size, when compared with the I/R group, which was consistent with the significant lower levels of plasma CK activity and caspase-3 activity, and that it increased the expression of HIF-1α in hyperlipidemic rats. When DMOG was given before PostC to up-regulate HIF-1α protein level, the degree of I/R injury was attenuated. In conclusion, these data suggested that the up-regulation of HIF-1α may be one of the cardioprotective mechanisms of PostC against I/R injury in hyperlipidemic rats.

  1. The prevention and treatment of hypoadiponectinemia-associated human diseases by up-regulation of plasma adiponectin.

    PubMed

    Hossain, Md Murad; Mukheem, Abdul; Kamarul, Tunku

    2015-08-15

    Hypoadiponectinemia is characterized by low plasma adiponectin levels that can be caused by genetic factors, such as single nucleotide polymorphisms (SNPs) and mutations in the adiponectin gene or by visceral fat deposition/obesity. Reports have suggested that hypoadiponectinemia is associated with dyslipidemia, hypertension, hyperuricemia, metabolic syndrome, atherosclerosis, type 2 diabetes mellitus and various cardiovascular diseases. Previous studies have highlighted several potential strategies to up-regulate adiponectin secretion and function, including visceral fat reduction through diet therapy and exercise, administration of exogenous adiponectin, treatment with peroxisome proliferator-activating receptor gamma (PPARγ) agonists (e.g., thiazolidinediones (TZDs)) and ligands (e.g., bezafibrate and fenofibrate) or the blocking of the renin-angiotensin system. Likewise, the up-regulation of the expression and stimulation of adiponectin receptors by using adiponectin receptor agonists would be an effective method to treat obesity-related conditions. Notably, adiponectin is an abundantly expressed bioactive protein that also exhibits a wide spectrum of biological properties, such as insulin-sensitizing, anti-diabetic, anti-inflammatory and anti-atherosclerotic activities. Although targeting adiponectin and its receptors has been useful for treating diabetes and other metabolic-related diseases in experimental studies, current drug development based on adiponectin/adiponectin receptors for clinical applications is scarce, and there is a lack of available clinical trial data. This comprehensive review discusses the strategies that are presently being pursued to harness the potential of adiponectin up-regulation. In addition, we examined the current status of drug development and its potential for clinical applications. PMID:25818192

  2. Timing Is Everything: Coordinated Control of Host Shutoff by Influenza A Virus NS1 and PA-X Proteins.

    PubMed

    Khaperskyy, Denys A; McCormick, Craig

    2015-07-01

    Like all viruses, influenza viruses (IAVs) use host translation machinery to decode viral mRNAs. IAVs ensure efficient translation of viral mRNAs through host shutoff, a process whereby viral proteins limit the accumulation of host proteins through subversion of their biogenesis. Despite its small genome, the virus deploys multiple host shutoff mechanisms at different stages of infection, thereby ensuring successful replication while limiting the communication of host antiviral responses. In this Gem, we review recent data on IAV host shutoff proteins, frame the outstanding questions in the field, and propose a temporally coordinated model of IAV host shutoff.

  3. Up-Regulation of Claudin-6 in the Distal Lung Impacts Secondhand Smoke-Induced Inflammation

    PubMed Central

    Lewis, Joshua B.; Milner, Dallin C.; Lewis, Adam L.; Dunaway, Todd M.; Egbert, Kaleb M.; Albright, Scott C.; Merrell, Brigham J.; Monson, Troy D.; Broberg, Dallin S.; Gassman, Jason R.; Thomas, Daniel B.; Arroyo, Juan A.; Reynolds, Paul R.

    2016-01-01

    It has long been understood that increased epithelial permeability contributes to inflammation observed in many respiratory diseases. Recently, evidence has revealed that environmental exposure to noxious material such as cigarette smoke reduces tight junction barrier integrity, thus enhancing inflammatory conditions. Claudin-6 (Cldn6) is a tetraspanin transmembrane protein found within the tight junctional complex and is implicated in maintaining lung epithelial barriers. To test the hypothesis that increased Cldn6 ameliorates inflammation at the respiratory barrier, we utilized the Tet-On inducible transgenic system to conditionally over-express Clnd6 in the distal lung. Cldn6 transgenic (TG) and control mice were continuously provided doxycycline from postnatal day (PN) 30 until euthanasia date at PN90. A subset of Cldn6 TG and control mice were also subjected to daily secondhand tobacco smoke (SHS) via a nose only inhalation system from PN30-90 and compared to room air (RA) controls. Animals were euthanized on PN90 and lungs were harvested for histological and molecular characterization. Bronchoalveolar lavage fluid (BALF) was procured for the assessment of inflammatory cells and molecules. Quantitative RT-PCR and immunoblotting revealed increased Cldn6 expression in TG vs. control animals and SHS decreased Cldn6 expression regardless of genetic up-regulation. Histological evaluations revealed no adverse pulmonary remodeling via Hematoxylin and Eosin (H&E) staining or any qualitative alterations in the abundance of type II pneumocytes or proximal non-ciliated epithelial cells via staining for cell specific propeptide of Surfactant Protein-C (proSP-C) or Club Cell Secretory Protein (CCSP), respectively. Immunoblotting and qRT-PCR confirmed the differential expression of Cldn6 and the pro-inflammatory cytokines TNF-α and IL-1β. As a general theme, inflammation induced by SHS exposure was influenced by the availability of Cldn6. These data reveal captivating

  4. Quantitative Proteomic Analysis Revealed 4-(methylnitrosamino)-1-(3-pyridinyl)-1-butanone-induced Up-regulation of 20S Proteasome in Cultured Human Fibroblast Cells

    PubMed Central

    Prins, John M.; Wang, Yinsheng

    2012-01-01

    The tobacco-specific N-nitrosamine, 4-(methylnitrosamino)-1-(3-pyridinyl)-1-butanone (NNK), is a well-known carcinogen. Although the ability of the metabolically activated form of NNK to generate DNA adducts is well established, little is known about the cellular pathways perturbed by NNK in its native state. In this study, we utilized stable isotope labeling by amino acid in cell culture (SILAC), together with mass spectrometry, to assess the perturbation of protein expression in GM00637 human skin fibroblast cells upon NNK exposure. With this approach, we were able to quantify 1412 proteins and 137 of them were with significantly altered expression following NNK exposure, including the up-regulation of all subunits of the 20S proteasome core complex. The up-regulation of the 20S core complex was also reflected by a significant increase in 20S proteasome activities in GM00637, IMR90 and MCF-7 cells upon NNK treatment. Furthermore, the β-adrenergic receptor (β-AR) antagonist propranolol could attenuate significantly the NNK-induced increase in proteasome activity in all the three cell lines, suggesting that up-regulation of the 20S proteasome may be mediated through the β-AR. Additionally, we found that NNK treatment altered the expression levels of other important proteins including mitochondrial proteins, cytoskeleton-associated proteins, and proteins involved in glycolysis and gluconeogenesis. Results from the present study provided novel insights into the cellular mechanisms targeted by NNK. PMID:22369695

  5. Up-regulation in the expression of renin gene by the influence of aluminium.

    PubMed

    Ezomo, Ojeiru F; Matsushima, Fumiko; Meshitsuka, Shunsuke

    2009-11-01

    The excretion of aluminium in urine was significantly increased after intake of analgesics containing aluminium, confirming increased absorption and hence exposure to aluminium with such medication. The effect of aluminium on the kidney was further investigated by study of gene expression in mice. After a single dose of aluminium, an up-regulation of renin gene was found by DNA sequencing of the products of differential display analysis. The up-regulation of renin was confirmed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting experiments in the dose dependent treatments and the time course observation after aluminium citrate injection. The up-regulation of the renin expression by aluminium is a strong indication of the influence of aluminium on the renin-angiotensin-aldosterone-system, resulting in possible induction of essential hypertension.

  6. Up-regulation of emotional responses to reward-predicting stimuli: an ERP study.

    PubMed

    Langeslag, Sandra J E; van Strien, Jan W

    2013-09-01

    Altered reward processing is a hallmark symptom of many psychiatric disorders. It has recently been shown that people are capable of down-regulating reward processing. Here, we examined whether people are capable of up-regulating emotional responses to reward-predicting stimuli. Participants passively viewed colored squares that predicted a reward or no reward, and up- or down-regulated their emotional responses to these reward-predicting stimuli by focusing on the reward meaning or the color of the squares respectively. The amplitude of the late positive potential (LPP) was taken as an objective index of regulation success. The LPP in response to reward-predicting squares was enhanced by up-regulation, suggesting that up-regulation of emotional responses to reward-predicting stimuli using a cognitive strategy is feasible. These results are highly relevant for the treatment of disorders characterized by diminished motivation, and for reward-based decision making in daily life. PMID:23770414

  7. Mu opioid receptor up-regulation and participation in excitability of hippocampal pyramidal cell electrophysiology

    SciTech Connect

    Moudy, A.M.

    1988-01-01

    Chronic administration of opiate antagonists to rats results in up-regulation of their brain opioid receptors. Using subcellular fractionation techniques, brain opioid receptors were resolved into two membrane populations, one associated with synaptic plasma membranes (SPM) and the other enriched in smooth endoplasmic reticulum and Golgi (microsomes). This study addressed in part the question of whether an antagonist induces up-regulation uniformly in these two populations. Rats were administered naltrexone by subcutaneously implanted osmotic minipumps. Forebrain mu receptor levels were determined by homologous displacement of ({sup 3}H)D-ala{sup 2}-mePhe{sup 4}-gly-ol{sup 5}-enkephalin (DAGO) followed by computer estimation of binding parameters. Receptor levels in crude membranes rose 77% after treatment. Microsomes displayed a 92% increase, a two-fold greater change than in SPMs (51%). These results establish that naltrexone induces up-regulation of both membrane populations; and that microsomal and SPM receptors represent discrete populations of intracellular and cell surface sites, respectively. Binding experiments on isolated hippocampi also demonstrated up-regulation (71%) of mu receptors. To demonstrate up-regulation of opioid receptors electrophysiologically, hippocampal slices were prepared from rats which had been chronically treated with naltrexone. After superfusion with DAGO, these slices showed a 42% greater population spike output than controls in response to the same EPSP input. Hippocampi from animals treated for two weeks showed an additional increase in sensitivity. The results support a disinhibitory role for opioids in pyramidal cell hyper-excitability. More importantly, they demonstrate a significant physiological correlate to opioid receptor up-regulation.

  8. Adenosine A2A Receptor Up-Regulates Retinal Wave Frequency via Starburst Amacrine Cells in the Developing Rat Retina

    PubMed Central

    Huang, Pin-Chien; Hsiao, Yu-Tien; Kao, Shao-Yen; Chen, Ching-Feng; Chen, Yu-Chieh; Chiang, Chung-Wei; Lee, Chien-fei; Lu, Juu-Chin; Chern, Yijuang; Wang, Chih-Tien

    2014-01-01

    Background Developing retinas display retinal waves, the patterned spontaneous activity essential for circuit refinement. During the first postnatal week in rodents, retinal waves are mediated by synaptic transmission between starburst amacrine cells (SACs) and retinal ganglion cells (RGCs). The neuromodulator adenosine is essential for the generation of retinal waves. However, the cellular basis underlying adenosine's regulation of retinal waves remains elusive. Here, we investigated whether and how the adenosine A2A receptor (A2AR) regulates retinal waves and whether A2AR regulation of retinal waves acts via presynaptic SACs. Methodology/Principal Findings We showed that A2AR was expressed in the inner plexiform layer and ganglion cell layer of the developing rat retina. Knockdown of A2AR decreased the frequency of spontaneous Ca2+ transients, suggesting that endogenous A2AR may up-regulate wave frequency. To investigate whether A2AR acts via presynaptic SACs, we targeted gene expression to SACs by the metabotropic glutamate receptor type II promoter. Ca2+ transient frequency was increased by expressing wild-type A2AR (A2AR-WT) in SACs, suggesting that A2AR may up-regulate retinal waves via presynaptic SACs. Subsequent patch-clamp recordings on RGCs revealed that presynaptic A2AR-WT increased the frequency of wave-associated postsynaptic currents (PSCs) or depolarizations compared to the control, without changing the RGC's excitability, membrane potentials, or PSC charge. These findings suggest that presynaptic A2AR may not affect the membrane properties of postsynaptic RGCs. In contrast, by expressing the C-terminal truncated A2AR mutant (A2AR-ΔC) in SACs, the wave frequency was reduced compared to the A2AR-WT, but was similar to the control, suggesting that the full-length A2AR in SACs is required for A2AR up-regulation of retinal waves. Conclusions/Significance A2AR up-regulates the frequency of retinal waves via presynaptic SACs, requiring its full

  9. Up-Regulated Expression of LAMP2 and Autophagy Activity during Neuroendocrine Differentiation of Prostate Cancer LNCaP Cells

    PubMed Central

    Vara-Ciruelos, Diana; Ramos-Torres, Ágata; Altamirano-Dimas, Manuel; Díaz-Laviada, Inés; Rodríguez-Henche, Nieves

    2016-01-01

    Neuroendocrine (NE) prostate cancer (PCa) is a highly aggressive subtype of prostate cancer associated with resistance to androgen ablation therapy. In this study, we used LNCaP prostate cancer cells cultured in a serum-free medium for 6 days as a NE model of prostate cancer. Serum deprivation increased the expression of NE markers such as neuron-specific enolase (NSE) and βIII tubulin (βIII tub) and decreased the expression of the androgen receptor protein in LNCaP cells. Using cDNA microarrays, we compared gene expression profiles of NE cells and non-differentiated LNCaP cells. We identified up-regulation of 155 genes, among them LAMP2, a lysosomal membrane protein involved in lysosomal stability and autophagy. We then confirmed up-regulation of LAMP2 in NE cells by qRT-PCR, Western blot and confocal microscopy assays, showing that mRNA up-regulation correlated with increased levels of LAMP2 protein. Subsequently, we determined autophagy activity in NE cells by assessing the protein levels of SQSTM/p62 and LC3 by Western blot and LC3 and Atg5 mRNAs content by qRT-PCR. The decreased levels of SQSTM/p62 was accompanied by an enhanced expression of LC3 and ATG5, suggesting activation of autophagy in NE cells. Blockage of autophagy with 1μM AKT inhibitor IV, or by silencing Beclin 1 and Atg5, prevented NE cell differentiation, as revealed by decreased levels of the NE markers. In addition, AKT inhibitor IV as well as Beclin1 and Atg5 kwockdown attenuated LAMP2 expression in NE cells. On the other hand, LAMP2 knockdown by siRNA led to a marked blockage of autophagy, prevention of NE differentiation and decrease of cell survival. Taken together, these results suggest that LAMP2 overexpression assists NE differentiation of LNCaP cells induced by serum deprivation and facilitates autophagy activity in order to attain the NE phenotype and cell survival. LAMP2 could thus be a potential biomarker and potential target for NE prostate cancer. PMID:27627761

  10. Up-Regulated Expression of LAMP2 and Autophagy Activity during Neuroendocrine Differentiation of Prostate Cancer LNCaP Cells.

    PubMed

    Morell, Cecilia; Bort, Alicia; Vara-Ciruelos, Diana; Ramos-Torres, Ágata; Altamirano-Dimas, Manuel; Díaz-Laviada, Inés; Rodríguez-Henche, Nieves

    2016-01-01

    Neuroendocrine (NE) prostate cancer (PCa) is a highly aggressive subtype of prostate cancer associated with resistance to androgen ablation therapy. In this study, we used LNCaP prostate cancer cells cultured in a serum-free medium for 6 days as a NE model of prostate cancer. Serum deprivation increased the expression of NE markers such as neuron-specific enolase (NSE) and βIII tubulin (βIII tub) and decreased the expression of the androgen receptor protein in LNCaP cells. Using cDNA microarrays, we compared gene expression profiles of NE cells and non-differentiated LNCaP cells. We identified up-regulation of 155 genes, among them LAMP2, a lysosomal membrane protein involved in lysosomal stability and autophagy. We then confirmed up-regulation of LAMP2 in NE cells by qRT-PCR, Western blot and confocal microscopy assays, showing that mRNA up-regulation correlated with increased levels of LAMP2 protein. Subsequently, we determined autophagy activity in NE cells by assessing the protein levels of SQSTM/p62 and LC3 by Western blot and LC3 and Atg5 mRNAs content by qRT-PCR. The decreased levels of SQSTM/p62 was accompanied by an enhanced expression of LC3 and ATG5, suggesting activation of autophagy in NE cells. Blockage of autophagy with 1μM AKT inhibitor IV, or by silencing Beclin 1 and Atg5, prevented NE cell differentiation, as revealed by decreased levels of the NE markers. In addition, AKT inhibitor IV as well as Beclin1 and Atg5 kwockdown attenuated LAMP2 expression in NE cells. On the other hand, LAMP2 knockdown by siRNA led to a marked blockage of autophagy, prevention of NE differentiation and decrease of cell survival. Taken together, these results suggest that LAMP2 overexpression assists NE differentiation of LNCaP cells induced by serum deprivation and facilitates autophagy activity in order to attain the NE phenotype and cell survival. LAMP2 could thus be a potential biomarker and potential target for NE prostate cancer. PMID:27627761

  11. Rac Regulates Giardia lamblia Encystation by Coordinating Cyst Wall Protein Trafficking and Secretion

    PubMed Central

    Krtková, Jana; Thomas, Elizabeth B.; Alas, Germain C. M.; Schraner, Elisabeth M.; Behjatnia, Habib R.; Hehl, Adrian B.

    2016-01-01

    ABSTRACT Encystation of the common intestinal parasite Giardia lamblia involves the production, trafficking, and secretion of cyst wall material (CWM). However, the molecular mechanism responsible for the regulation of these sequential processes remains elusive. Here, we examined the role of GlRac, Giardia’s sole Rho family GTPase, in the regulation of endomembrane organization and cyst wall protein (CWP) trafficking. Localization studies indicated that GlRac is associated with the endoplasmic reticulum (ER) and the Golgi apparatus-like encystation-specific vesicles (ESVs). Constitutive GlRac signaling increased levels of the ER marker PDI2, induced ER swelling, reduced overall CWP1 production, and promoted the early maturation of ESVs. Quantitative analysis of cells expressing constitutively active hemagglutinin (HA)-tagged GlRac (HA-RacCA) revealed fewer but larger ESVs than control cells. Consistent with the phenotype of premature maturation of ESVs in HA-RacCA-expressing cells, constitutive GlRac signaling resulted in increased CWP1 secretion and, conversely, morpholino depletion of GlRac blocked CWP1 secretion. Wild-type cells unexpectedly secreted large quantities of CWP1 into the medium, and free CWP1 was used cooperatively during cyst formation. These results, in part, could account for the previously reported observation that G. lamblia encysts more efficiently at high cell densities. These studies of GlRac show that it regulates encystation at several levels, and our findings support its coordinating role as a regulator of CWP trafficking and secretion. The central role of GlRac in regulating membrane trafficking and the cytoskeleton, both of which are essential to Giardia parasitism, further suggests its potential as a novel target for drug development to treat giardiasis. PMID:27555307

  12. Up-regulation of a cysteine protease accompanies the ethylene-insensitive senescence of daylily (Hemerocallis) flowers.

    PubMed

    Valpuesta, V; Lange, N E; Guerrero, C; Reid, M S

    1995-06-01

    The flowers of daylily (Hemerocallis x hybrida cv. Cradle Song) open at midnight, start to senesce 12 h later, and are completely senescent by the following midnight. Differential screening of a cDNA library constructed from tepals of flowers showing incipient senescence revealed 25 clones that were strongly up-regulated in senescent tepals. Re-screening and interactive Southern analysis of these clones revealed 3 families of up-regulated clones. Transcripts of one clone, SEN10, were not detectable at midnight, but increased dramatically as senescence proceeded. The derived amino acid sequence of the full-length cDNA (SEN102) has strong homology with cysteine proteases that have been reported from other plant tissues. The sequence contains a secretory signal peptide and a probable prosequence upstream of the mature protein. Amino acids critical to the active site and structure of cysteine proteases are conserved, and the C-terminus of the polypeptide has a unique putative endoplasmic reticulum retention signal -RDEL. PMID:7632925

  13. Transcutaneous electrical nerve stimulation (TENS) improves the diabetic cytopathy (DCP) via up-regulation of CGRP and cAMP.

    PubMed

    Ding, Liucheng; Song, Tao; Yi, Chaoran; Huang, Yi; Yu, Wen; Ling, Lin; Dai, Yutian; Wei, Zhongqing

    2013-01-01

    The objective of this study was to investigate the effects and mechanism of Transcutaneous Electrical Nerve Stimulation (TENS) on the diabetic cytopathy (DCP) in the diabetic bladder. A total of 45 rats were randomly divided into diabetes mellitus (DM)/TENS group (n=15), DM group (n=15) and control group (n=15). The rats in the DM/TENS and TENS groups were electronically stimulated (stimulating parameters: intensity-31 V, frequency-31 Hz, and duration of stimulation of 15 min) for three weeks. Bladder histology, urodynamics and contractile responses to field stimulation and carbachol were determined. The expression of calcitonin gene-related peptide (CGRP) was analyzed by RT-PCR and Western blotting. The results showed that contractile responses of the DM rats were ameliorated after 3 weeks of TENS. Furthermore, TENS significantly increased bladder wet weight, volume threshold for micturition and reduced PVR, V% and cAMP content of the bladder. The mRNA and protein levels of CGRP in dorsal root ganglion (DRG) in the DM/TENS group were higher than those in the DM group. TENS also significantly up-regulated the cAMP content in the bladder body and base compared with diabetic rats. We conclude that TENS can significantly improve the urine contractility and ameliorate the feeling of bladder fullness in DM rats possibly via up-regulation of cAMP and CGRP in DRG.

  14. A unique phosphorylation-dependent eIF4E assembly on 40S ribosomes co-ordinated by hepatitis C virus protein NS5A that activates internal ribosome entry site translation.

    PubMed

    Panda, Swarupa; Vedagiri, Dhiviya; Viveka, Thangaraj Soundara; Harshan, Krishnan Harinivas

    2014-09-01

    We previously reported that the HCV (hepatitis C virus) protein NS5A up-regulated mRNA cap binding eIF4F (eukaryotic initiation factor 4F) complex assembly through mTOR (mechanistic target of rapamycin)-4EBP1 (eIF4E-binding protein 1) pathway and that NS5A (non-structural protein 5A) physically interacted with translation apparatus. In the present study, we demonstrate that NS5A co-ordinates a unique assembly of the cap binding protein eIF4E and 40S ribosome to form a complex that we call ENR (eIF4E-NS5A-ribosome). Recruitment of NS5A and eIF4E to 40S ribosome was confirmed by polysome fractionation, subcellular fractionation and high-salt-wash immunoprecipitation. These observations were also confirmed in HCV-infected cells, validating its biological significance. eIF4E phosphorylation was critical for ENR assembly. 80S ribosome dissociation and RNase integrity assays revealed that, once associated, the ENR complex is stable and RNA interaction is dispensable. Both the N- and C-terminal regions of NS5A domain 1 were indispensable for this assembly and for the NS5A-induced HCV IRES (internal ribosome entry site) activation. The present study demonstrates that NS5A initially associates with phosphorylated eIF4E of eIF4F complex and subsequently recruits it to 40S ribosomes. This is the first time the interaction of viral protein with both eIF4E and ribosomes has been reported. We propose that this assembly would determine the outcome of HCV infection and pathogenesis through regulation of viral and host translation.

  15. Representation of protein 3D structures in spherical (ρ, ϕ, θ) coordinates and two of its potential applications.

    PubMed

    Reyes, Vicente M

    2011-09-01

    Three-dimensional objects can be represented using cartesian, spherical or cylindrical coordinate systems, among many others. Currently all protein 3D structures in the PDB are in cartesian coordinates. We wanted to explore the possibility that protein 3D structures, especially the globular type (spheroproteins), when represented in spherical coordinates might find useful novel applications. A Fortran program was written to transform protein 3D structure files in cartesian coordinates (x,y,z) to spherical coordinates (ρ, ϕ, θ), with the centroid of the protein molecule as origin. We present here two applications, namely, (1) separation of the protein outer layer (OL) from the inner core (IC); and (2) identifying protrusions and invaginations on the protein surface. In the first application, ϕ and θ were partitioned into suitable intervals and the point with maximum ρ in each such 'ϕ-θ bin' was determined. A suitable cutoff value for ρ is adopted, and for each ϕ-θ bin, all points with ρ values less than the cutoff are considered part of the IC, and those with ρ values equal to or greater than the cutoff are considered part of the OL. We show that this separation procedure is successful as it gives rise to an OL that is significantly more enriched in hydrophilic amino acid residues, and an IC that is significantly more enriched in hydrophobic amino acid residues, as expected. In the second application, the point with maximum ρ in each ϕ-θ bin are sequestered and their frequency distribution constructed (i.e., maximum ρ's sorted from lowest to highest, collected into 1.50Å-intervals, and the frequency in each interval plotted). We show in such plots that invaginations on the protein surface give rise to subpeaks or shoulders on the lagging side of the main peak, while protrusions give rise to similar subpeaks or shoulders, but on the leading side of the main peak. We used the dataset of Laskowski et al. (1996) to demonstrate both applications.

  16. Representation of protein 3D structures in spherical (ρ, ϕ, θ) coordinates and two of its potential applications.

    PubMed

    Reyes, Vicente M

    2011-09-01

    Three-dimensional objects can be represented using cartesian, spherical or cylindrical coordinate systems, among many others. Currently all protein 3D structures in the PDB are in cartesian coordinates. We wanted to explore the possibility that protein 3D structures, especially the globular type (spheroproteins), when represented in spherical coordinates might find useful novel applications. A Fortran program was written to transform protein 3D structure files in cartesian coordinates (x,y,z) to spherical coordinates (ρ, ϕ, θ), with the centroid of the protein molecule as origin. We present here two applications, namely, (1) separation of the protein outer layer (OL) from the inner core (IC); and (2) identifying protrusions and invaginations on the protein surface. In the first application, ϕ and θ were partitioned into suitable intervals and the point with maximum ρ in each such 'ϕ-θ bin' was determined. A suitable cutoff value for ρ is adopted, and for each ϕ-θ bin, all points with ρ values less than the cutoff are considered part of the IC, and those with ρ values equal to or greater than the cutoff are considered part of the OL. We show that this separation procedure is successful as it gives rise to an OL that is significantly more enriched in hydrophilic amino acid residues, and an IC that is significantly more enriched in hydrophobic amino acid residues, as expected. In the second application, the point with maximum ρ in each ϕ-θ bin are sequestered and their frequency distribution constructed (i.e., maximum ρ's sorted from lowest to highest, collected into 1.50Å-intervals, and the frequency in each interval plotted). We show in such plots that invaginations on the protein surface give rise to subpeaks or shoulders on the lagging side of the main peak, while protrusions give rise to similar subpeaks or shoulders, but on the leading side of the main peak. We used the dataset of Laskowski et al. (1996) to demonstrate both applications. PMID

  17. Methamphetamine and 3,4-methylenedioxymethamphetamine interact with central nicotinic receptors and induce their up-regulation

    SciTech Connect

    Garcia-Rates, Sara; Camarasa, Jordi; Escubedo, Elena; Pubill, David

    2007-09-15

    Previous work from our group indicated that {alpha}7 nicotinic acetylcholine receptors ({alpha}7 nAChR) potentially play a role in methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA) neurotoxicity. The aims of the present study were two-fold: (1) to demonstrate the interaction of METH and MDMA with homomeric {alpha}7 nAChR ([{sup 3}H]methyllycaconitine binding) and other heteromeric subtypes ([{sup 3}H]epibatidine binding); and (2) to show the effects of amphetamine derivative pretreatment on the density of binding sites. METH and MDMA displaced [{sup 3}H]methyllycaconitine and [{sup 3}H]epibatidine binding in membranes from NGF-differentiated PC 12 cells and mouse brain, with K{sub i} values in the micromolar range, MDMA revealing a greater affinity than METH. In addition, METH and MDMA induced a time- and concentration-dependent increase in [{sup 3}H]methyllycaconitine and [{sup 3}H]epibatidine binding; which had already been apparent after 6 h of pretreatment, and which peaked in differentiated PC 12 cells after 48 h. The highest increases were found in [{sup 3}H]epibatidine binding, with MDMA inducing higher increases than METH. Treatment with METH and MDMA increased B{sub max} of high-affinity sites for both radioligands without affecting K{sub d}. The heightened binding was inhibited by pretreatment with cycloheximide, suggesting the participation of newly synthesised proteins while inhibition of protein trafficking to plasma membrane did not block up-regulation. The effects of protein kinase and cyclophilin inhibitors on such up-regulation were explored, revealing a rapid, differential and complex regulation, similar to that described for nicotinic ligands. All of these results demonstrate that METH and MDMA have affinity for, and can interact with, nAChR, inducing their up-regulation, specially when higher doses are used. Such effects may have a role in METH- and MDMA-induced neurotoxicity, cholinergic neurotransmission, and in processes

  18. Executive functions and the down-regulation and up-regulation of emotion

    PubMed Central

    Gyurak, Anett; Goodkind, Madeleine S.; Kramer, Joel H.; Miller, Bruce L.; Levenson, Robert W.

    2011-01-01

    This study examined the relationship between individual differences in executive functions (EF; assessed by measures of working memory, Stroop, trail making, and verbal fluency) and ability to down-regulate and up-regulate responses to emotionally evocative film clips. To ensure a wide range of EF, 48 participants with diverse neurodegenerative disorders and 21 older neurologically normal aging participants were included. Participants were exposed to three different movie clips that were designed to elicit a mix of disgust and amusement. While watching the films they were either instructed to watch, down-regulate, and up-regulate their visible emotional responses. Heart-rate and facial behaviors were monitored throughout. Emotion regulatory ability was operationalized as changes in heart-rate and facial behavior in the down- and up-regulation conditions, controlling for responses in the watch condition. Results indicated that higher verbal fluency scores were related to greater ability to regulate emotion in both the down-regulation and up-regulation conditions. This finding remained significant even after controlling for age and general cognitive functioning. No relationships were found between emotion regulation and the other EF measures. We believe these results derive from differences among EF measures, with verbal fluency performance best capturing the complex sequence of controlled planning, activation, and monitoring required for successful emotion regulation. These findings contribute to our understanding of emotion-cognition interaction, suggesting a link between emotion-regulatory abilities and individual differences in complex executive functions. PMID:21432634

  19. Impaired up-regulation of type II corticosteroid receptors in hippocampus of aged rats.

    PubMed

    Eldridge, J C; Fleenor, D G; Kerr, D S; Landfield, P W

    1989-01-30

    Several recent investigations have reported a decline of rat hippocampal corticosteroid-binding receptors (CSRs) with aging. This decline has been proposed to be an initial cause (through disinhibition) of the elevated adrenal steroid secretion that apparently occurs with aging; however, it could instead be an effect of corticoid elevation (through down-regulation). In order to assess the effects of age on CSR biosynthetic capacity in the absence of down-regulatory influences of endogenous corticoids, as well as to study aging changes in CSR plasticity, we examined the up-regulation of hippocampal CSR that follows adrenalectomy (ADX). The rat hippocampus contains at least two types of CSR binding and differential analysis of types I and II CSR was accomplished by selective displacement of [3H]corticosterone with RU-28362, a specific type II agonist. In young (3 months old) Fischer-344 rat hippocampus, up-regulation of type II binding above 2-day ADX baseline was present by 3-7 days and increased still further by 8-10 days post-ADX; type I CSR density did not change significantly between 1 and 10 days post-ADX. However, in aged (24-26 months old) rats, type II CSR up-regulation did not occur over the 10 day post-ADX period. Thus, the age-related impairment of type II up-regulation may reflect an intrinsic deficit in CSR biosynthesis or lability that is independent of the acute endogenous adrenal steroid environment.

  20. Fibulin 2, a Tyrosine O-Sulfated Protein, Is Up-regulated Following Retinal Detachment*

    PubMed Central

    Kanan, Yogita; Brobst, Daniel; Han, Zongchao; Naash, Muna I.; Al-Ubaidi, Muayyad R.

    2014-01-01

    Retinal detachment is the physical separation of the retina from the retinal pigment epithelium. It occurs during aging, trauma, or during a variety of retinal disorders such as age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity, or as a complication following cataract surgery. This report investigates the role of fibulin 2, an extracellular component, in retinal detachment. A major mechanism for detachment resolution is enhancement of cellular adhesion between the retina and the retinal pigment epithelium and prevention of its cellular migration. This report shows that fibulin 2 is mainly present in the retinal pigment epithelium, Bruch membrane, choriocapillary, and to a lesser degree in the retina. In vitro studies revealed the presence of two isoforms for fibulin 2. The small isoform is located inside the cell, and the large isoform is present inside and outside the cells. Furthermore, fibulin 2 is post-translationally modified by tyrosine sulfation, and the sulfated isoform is present outside the cell, whereas the unsulfated pool is internally located. Interestingly, sulfated fibulin 2 significantly reduced the rate of cellular growth and migration. Finally, levels of fibulin 2 dramatically increased in the retinal pigment epithelium following retinal detachment, suggesting a direct role for fibulin 2 in the re-attachment of the retina to the retinal pigment epithelium. Understanding the role of fibulin 2 in enhancing retinal attachment is likely to help improve the current therapies or allow the development of new strategies for the treatment of this sight-threatening condition. PMID:24692557

  1. Simvastatin alleviates cardiac fibrosis induced by infarction via up-regulation of TGF-β receptor III expression

    PubMed Central

    Sun, Fei; Duan, Wenqi; Zhang, Yu; Zhang, Lingling; Qile, Muge; Liu, Zengyan; Qiu, Fang; Zhao, Dan; Lu, Yanjie; Chu, Wenfeng

    2015-01-01

    Background and Purpose Statins decrease heart disease risk, but their mechanisms are not completely understood. We examined the role of the TGF-β receptor III (TGFBR3) in the inhibition of cardiac fibrosis by simvastatin. Experimental Approach Myocardial infarction (MI) was induced by ligation of the left anterior descending coronary artery in mice given simvastatin orally for 7 days. Cardiac fibrosis was measured by Masson staining and electron microscopy. Heart function was evaluated by echocardiography. Signalling through TGFBR3, ERK1/2, JNK and p38 pathways was measured using Western blotting. Collagen content and cell viability were measured in cultures of neonatal mouse cardiac fibroblasts (NMCFs). Interactions between TGFBR3 and the scaffolding protein, GAIP-interacting protein C-terminus (GIPC) were detected using co-immunoprecipitation (co-IP). In vivo, hearts were injected with lentivirus carrying shRNA for TGFBR3. Key Results Simvastatin prevented fibrosis following MI, improved heart ultrastructure and function, up-regulated TGFBR3 and decreased ERK1/2 and JNK phosphorylation. Simvastatin up-regulated TGFBR3 in NMCFs, whereas silencing TGFBR3 reversed inhibitory effects of simvastatin on cell proliferation and collagen production. Simvastatin inhibited ERK1/2 and JNK signalling while silencing TGFBR3 opposed this effect. Co-IP demonstrated TGFBR3 binding to GIPC. Overexpressing TGFBR3 inhibited ERK1/2 and JNK signalling which was abolished by knock-down of GIPC. In vivo, suppression of cardiac TGFBR3 abolished anti-fibrotic effects, improvement of cardiac function and changes in related proteins after simvastatin. Conclusions and Implications TGFBR3 mediated the decreased cardiac fibrosis, collagen deposition and fibroblast activity, induced by simvastatin, following MI. These effects involved GIPC inhibition of the ERK1/2/JNK pathway. PMID:25884615

  2. Tissue specific up regulation of ACE2 in rabbit model of atherosclerosis by atorvastatin: role of epigenetic histone modifications.

    PubMed

    Tikoo, Kulbhushan; Patel, Gaurang; Kumar, Sandeep; Karpe, Pinakin Arun; Sanghavi, Maitri; Malek, Vajir; Srinivasan, K

    2015-02-01

    Growing body of evidence points out the crucial role of ACE2 in preventing atherosclerosis. However, data on how atherosclerosis affects ACE2 expression in heart and kidney remains unknown. Atherosclerosis was induced by feeding New Zealand White rabbits with high cholesterol diet (HCD - 2%) for 12 weeks and atorvastatin was administered (5mg/kg/day p.o) in last 3 weeks. ACE2 mRNA and protein expression was assessed by Western blotting and real time PCR. HCD fed rabbits developed atherosclerosis as confirmed by increase in plasma total cholesterol, LDL and triglycerides as well as formation atherosclerotic plaques in arch of aorta. The ACE2 protein but not mRNA expression was reduced in heart and kidney of HCD rabbits. Interestingly, atorvastatin increased the ACE2 protein expression in heart and kidney of HCD rabbits. However, atorvastatin increased ACE2 mRNA in heart but not in kidney of HCD rabbits. Atorvastatin increased the occupancy of histone H3 acetylation (H3-Ac) mark on ACE2 promoter region in heart of HCD rabbits indicating direct or indirect epigenetic up-regulation of ACE2 by atorvastatin. Further, atorvastatin suppressed Ang II-induced contractile responses and enhanced AT2 receptor mediated relaxant responses in atherosclerotic aorta. We propose that atherosclerosis is associated with reduced ACE2 expression in heart and kidney. We also show an unexplored potential of atorvastatin to up-regulate ACE2 via epigenetic histone modifications. Our data suggest a novel way of replenishing ACE2 expression for preventing not only atherosclerosis but also other cardiovascular disorders. PMID:25482567

  3. Ursolic Acid Attenuates Diabetic Mesangial Cell Injury through the Up-Regulation of Autophagy via miRNA-21/PTEN/Akt/mTOR Suppression

    PubMed Central

    Lu, Xinxing; Fan, Qiuling; Xu, Li; Li, Lin; Yue, Yuan; Xu, Yanyan; Su, Yan; Zhang, Dongcheng; Wang, Lining

    2015-01-01

    Objective To investigate the effect of ursolic acid on autophagy mediated through the miRNA-21-targeted phosphoinositide 3 kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway in rat mesangial cells cultured under high glucose (HG) conditions. Methods Rat glomerular mesangial cells were cultured under normal glucose, HG, HG with the PI3K inhibitor LY294002 or HG with ursolic acid conditions. Cell proliferation and hypertrophy were assayed using an MTT assay and the ratio of total protein to cell number, respectively. The miRNA-21 expression was detected using RT-qPCR. The expression of phosphatase and tensin homolog (PTEN)/AKT/mTOR signaling signatures, autophagy-associated protein and collagen I was detected by western blotting and RT-qPCR. Autophagosomes were observed using electron microscopy. Results Compared with mesangial cells cultured under normal glucose conditions, the cells exposed to HG showed up-regulated miRNA-21 expression, down-regulated PTEN protein and mRNA expression, up-regulated p85PI3K, pAkt, pmTOR, p62/SQSTMI, and collagen I expression and down-regulated LC3II expression. Ursolic acid and LY294002 inhibited HG-induced mesangial cell hypertrophy and proliferation, down-regulated p85PI3K, pAkt, pmTOR, p62/SQSTMI, and collagen I expression and up-regulated LC3II expression. However, LY294002 did not affect the expression of miRNA-21 and PTEN. Ursolic acid down-regulated miRNA-21 expression and up-regulated PTEN protein and mRNA expression. Conclusions Ursolic acid inhibits the glucose-induced up-regulation of mesangial cell miRNA-21 expression, up-regulates PTEN expression, inhibits the activation of PI3K/Akt/mTOR signaling pathway, and enhances autophagy to reduce the accumulation of the extracellular matrix and ameliorate cell hypertrophy and proliferation. PMID:25689721

  4. Up-regulation of DRP-3 long isoform during the induction of neural progenitor cells by glutamate treatment in the ex vivo rat retina

    SciTech Connect

    Tokuda, Kazuhiro; Kuramitsu, Yasuhiro; Byron, Baron; Kitagawa, Takao; Tokuda, Nobuko; Kobayashi, Daiki; Nagayama, Megumi; Araki, Norie; Sonoda, Koh-Hei; Nakamura, Kazuyuki

    2015-08-07

    Glutamate has been shown to induce neural progenitor cells in the adult vertebrate retina. However, protein dynamics during progenitor cell induction by glutamate are not fully understood. To identify specific proteins involved in the process, we employed two-dimensional electrophoresis-based proteomics on glutamate untreated and treated retinal ex vivo sections. Rat retinal tissues were incubated with 1 mM glutamate for 1 h, followed by incubation in glutamate-free media for a total of 24 h. Consistent with prior reports, it was found that mitotic cells appeared in the outer nuclear layer without any histological damage. Immunohistological evaluations and immunoblotting confirmed the emergence of neuronal progenitor cells in the mature retina treated with glutamate. Proteomic analysis revealed the up-regulation of dihydropyrimidinase-related protein 3 (DRP-3), DRP-2 and stress-induced-phosphoprotein 1 (STIP1) during neural progenitor cell induction by glutamate. Moreover, mRNA expression of DRP-3, especially, its long isoform, robustly increased in the treated retina compared to that in the untreated retina. These results may indicate that glutamate induces neural progenitor cells in the mature rat retina by up-regulating the proteins which mediate cell mitosis and neurite growth. - Highlights: • Glutamate induced neuronal progenitor cells in the mature rat retina. • Proteomic analysis revealed the up-regulation of DRP-3, DRP-2 and STIP1. • mRNA expression of DRP-3, especially, its long isoform, robustly increased.

  5. A novel family of Toxoplasma IMC proteins displays a hierarchical organization and functions in coordinating parasite division.

    PubMed

    Beck, Josh R; Rodriguez-Fernandez, Imilce A; de Leon, Jessica Cruz; Huynh, My-Hang; Carruthers, Vern B; Morrissette, Naomi S; Bradley, Peter J

    2010-09-09

    Apicomplexans employ a peripheral membrane system called the inner membrane complex (IMC) for critical processes such as host cell invasion and daughter cell formation. We have identified a family of proteins that define novel sub-compartments of the Toxoplasma gondii IMC. These IMC Sub-compartment Proteins, ISP1, 2 and 3, are conserved throughout the Apicomplexa, but do not appear to be present outside the phylum. ISP1 localizes to the apical cap portion of the IMC, while ISP2 localizes to a central IMC region and ISP3 localizes to a central plus basal region of the complex. Targeting of all three ISPs is dependent upon N-terminal residues predicted for coordinated myristoylation and palmitoylation. Surprisingly, we show that disruption of ISP1 results in a dramatic relocalization of ISP2 and ISP3 to the apical cap. Although the N-terminal region of ISP1 is necessary and sufficient for apical cap targeting, exclusion of other family members requires the remaining C-terminal region of the protein. This gate-keeping function of ISP1 reveals an unprecedented mechanism of interactive and hierarchical targeting of proteins to establish these unique sub-compartments in the Toxoplasma IMC. Finally, we show that loss of ISP2 results in severe defects in daughter cell formation during endodyogeny, indicating a role for the ISP proteins in coordinating this unique process of Toxoplasma replication.

  6. A novel copper(II) coordination at His186 in full-length murine prion protein

    SciTech Connect

    Watanabe, Yasuko; Hiraoka, Wakako; Igarashi, Manabu; Ito, Kimihito; Shimoyama, Yuhei; Horiuchi, Motohiro; Yamamori, Tohru; Yasui, Hironobu; Kuwabara, Mikinori; Inagaki, Fuyuhiko; Inanami, Osamu

    2010-04-09

    To explore Cu(II) ion coordination by His{sup 186} in the C-terminal domain of full-length prion protein (moPrP), we utilized the magnetic dipolar interaction between a paramagnetic metal, Cu(II) ion, and a spin probe introduced in the neighborhood of the postulated binding site by the spin labeling technique (SDSL technique). Six moPrP mutants, moPrP(D143C), moPrP(Y148C), moPrP(E151C), moPrP(Y156C), moPrP(T189C), and moPrP(Y156C,H186A), were reacted with a methane thiosulfonate spin probe and a nitroxide residue (R1) was created in the binding site of each one. Line broadening of the ESR spectra was induced in the presence of Cu(II) ions in moPrP(Y148R1), moPrP(Y151R1), moPrP(Y156R1), and moPrP(T189R1) but not moPrP(D143R1). This line broadening indicated the presence of electron-electron dipolar interaction between Cu(II) and the nitroxide spin probe, suggesting that each interspin distance was within 20 A. The interspin distance ranges between Cu(II) and the spin probes of moPrP(Y148R1), moPrP(Y151R1), moPrP(Y156R1), and moPrP(T189R1) were estimated to be 12.1 A, 18.1 A, 10.7 A, and 8.4 A, respectively. In moPrP(Y156R1,H186A), line broadening between Cu(II) and the spin probe was not observed. These results suggest that a novel Cu(II) binding site is involved in His186 in the Helix2 region of the C-terminal domain of moPrP{sup C}.

  7. Up-regulation of the clusterin gene after proteotoxic stress: implication of HSF1–HSF2 heterocomplexes

    PubMed Central

    Loison, Fabien; Debure, Laure; Nizard, Philippe; le Goff, Pascale; Michel, Denis; le Dréan, Yves

    2005-01-01

    Clusterin is a secreted protein chaperone up-regulated in several pathologies, including cancer and neurodegenerative diseases. The present study shows that accumulation of aberrant proteins, caused by the proteasome inhibitor MG132 or the incorporation of the amino acid analogue AZC (L-azetidine-2-carboxylic acid), increased both clusterin protein and mRNA levels in the human glial cell line U-251 MG. Consistently, MG132 treatment was capable of stimulating a 1.3 kb clusterin gene promoter. Promoter deletion and mutation studies revealed a critical MG132-responsive region between −218 and −106 bp, which contains a particular heat-shock element, named CLE for ‘clusterin element’. Gel mobility-shift assays demonstrated that MG132 and AZC treatments induced the formation of a protein complex that bound to CLE. As shown by supershift and chromatin-immunoprecipitation experiments, CLE is bound by HSF1 (heat-shock factor 1) and HSF2 upon proteasome inhibition. Furthermore, co-immunoprecipitation assays indicated that these two transcription factors interact. Gel-filtration analyses revealed that the HSF1–HSF2 heterocomplexes bound to CLE after proteasome inhibition have the same apparent mass as HSF1 homotrimers after heat shock, suggesting that HSF1 and HSF2 could heterotrimerize. Therefore these studies indicate that the clusterin is a good candidate to be part of a cellular defence mechanism against neurodegenerative diseases associated with misfolded protein accumulation or decrease in proteasome activity. PMID:16336210

  8. Characterization of a RacGTPase up-regulated in the large yellow croaker Pseudosciaena crocea immunity.

    PubMed

    Han, Fang; Wang, Xiaoqing; Yang, Qilian; Cai, Mingyi; Wang, Zhi Yong

    2011-02-01

    The Rac proteins are members of the Rho family of small G proteins and are implicated in the regulation of several pathways, including those leading to cytoskeleton reorganization, gene expression, cell proliferation, cell adhesion and cell migration and survival. In this investigation, a Rac gene (named as LycRac gene) was obtained from the large yellow croaker and it was expressed in Escherichia coli and purified. Subsequently the specific antibody was raised using the purified fusion protein (GST-LycRac). Moreover, the GTP-binding assay showed that the LycRac protein had GTP-binding activity. The LycRac gene was ubiquitously transcribed and expressed in 9 tissues. Quantitative real-time RT-PCR and Western blot analysis revealed the highest expression in gill and the weakest expression in spleen. Time-course analysis revealed that LycRac expression was obviously up-regulated in blood, spleen and liver after immunization with polyinosinic polycytidynic acid (poly I:C), formalin-inactive Gram-negative bacterium Vibrio parahemolyticus and bacterial lipopolysaccharides (LPS). These results suggested that LycRac protein might play an important role in the immune response against microorganisms in large yellow croaker. PMID:21130170

  9. Berberine up-regulates the BDNF expression in hippocampus and attenuates corticosterone-induced depressive-like behavior in mice.

    PubMed

    Shen, Ji-Duo; Ma, Li-Gang; Hu, Chun-Yue; Pei, Yang-Yi; Jin, Shuang-Li; Fang, Xiao-Yan; Li, Yu-Cheng

    2016-02-12

    Depression is increasingly become a global public healthy problem. This study was to investigate whether berberine could attenuate the depressive-like behavior induced by repeated corticosterone injection and explore the possible mechanisms. The present results showed that exogenous corticosterone injection caused depressive-like behaviors in mice, such as decreased sucrose intake in sucrose preference test (SPT) and increased immobility time in forced swimming test (FST). These behavioral alterations were accompanying with the decreased BDNF mRNA and protein levels in hippocampus and the elevated serum corticosterone levels. Treatment with berberine prevented these changes above. Our findings confirmed the antidepressant-like effect of berberine and suggested its mechanisms might be partially mediated by up-regulation of BDNF in hippocampus.

  10. Mannose receptor induces T-cell tolerance via inhibition of CD45 and up-regulation of CTLA-4.

    PubMed

    Schuette, Verena; Embgenbroich, Maria; Ulas, Thomas; Welz, Meike; Schulte-Schrepping, Jonas; Draffehn, Astrid M; Quast, Thomas; Koch, Katharina; Nehring, Melanie; König, Jessica; Zweynert, Annegret; Harms, Frederike L; Steiner, Nancy; Limmer, Andreas; Förster, Irmgard; Berberich-Siebelt, Friederike; Knolle, Percy A; Wohlleber, Dirk; Kolanus, Waldemar; Beyer, Marc; Schultze, Joachim L; Burgdorf, Sven

    2016-09-20

    The mannose receptor (MR) is an endocytic receptor involved in serum homeostasis and antigen presentation. Here, we identify the MR as a direct regulator of CD8(+) T-cell activity. We demonstrate that MR expression on dendritic cells (DCs) impaired T-cell cytotoxicity in vitro and in vivo. This regulatory effect of the MR was mediated by a direct interaction with CD45 on the T cell, inhibiting its phosphatase activity, which resulted in up-regulation of cytotoxic T-lymphocyte-associated Protein 4 (CTLA-4) and the induction of T-cell tolerance. Inhibition of CD45 prevented expression of B-cell lymphoma 6 (Bcl-6), a transcriptional inhibitor that directly bound the CTLA-4 promoter and regulated its activity. These data demonstrate that endocytic receptors expressed on DCs contribute to the regulation of T-cell functionality. PMID:27601670

  11. Growth differentiation factor 8 suppresses cell proliferation by up-regulating CTGF expression in human granulosa cells.

    PubMed

    Chang, Hsun-Ming; Pan, Hui-Hui; Cheng, Jung-Chien; Zhu, Yi-Min; Leung, Peter C K

    2016-02-15

    Connective tissue growth factor (CTGF) is a matricellular protein that plays a critical role in the development of ovarian follicles. Growth differentiation factor 8 (GDF8) is mainly, but not exclusively, expressed in the mammalian musculoskeletal system and is a potent negative regulator of skeletal muscle growth. The aim of this study was to investigate the effects of GDF8 and CTGF on the regulation of cell proliferation in human granulosa cells and to examine its underlying molecular determinants. Using dual inhibition approaches (inhibitors and small interfering RNAs), we have demonstrated that GDF8 induces the up-regulation of CTGF expression through the activin receptor-like kinase (ALK)4/5-mediated SMAD2/3-dependent signaling pathways. In addition, the increase in CTGF expression contributes to the GDF8-induced suppressive effect on granulosa cell proliferation. Our findings suggest that GDF8 and CTGF may play critical roles in the regulation of proliferative events in human granulosa cells.

  12. Caveolin-1 mediates tissue plasminogen activator-induced MMP-9 up-regulation in cultured brain microvascular endothelial cells.

    PubMed

    Jin, Xinchun; Sun, Yanyun; Xu, Ji; Liu, Wenlan

    2015-03-01

    Thrombolysis with tissue plasminogen activator (tPA) increases matrix metalloproteinase-9 (MMP-9) activity in the ischemic brain, which exacerbates blood-brain barrier injury and increases the risk of symptomatic cerebral hemorrhage. The mechanism through which tPA enhances MMP-9 activity is not well understood. Here we report an important role of caveolin-1 in mediating tPA-induced MMP-9 synthesis. Brain microvascular endothelial cell line bEnd3 cells were incubated with 5 or 20 μg/ml tPA for 24 hrs before analyzing MMP-9 levels in the conditioned media and cellular extracts by gelatin zymography. tPA at a dose of 20 μg/mL tPA, but not 5 μg/mL, significantly increased MMP-9 level in cultured media while decreasing it in cellular extracts. Concurrently, tPA treatment induced a 2.3-fold increase of caveolin-1 protein levels in endothelial cells. Interestingly, knockdown of Cav-1 with siRNA inhibited tPA-induced MMP-9 mRNA up-regulation and MMP-9 increase in the conditioned media, but did not affect MMP-9 decrease in cellular extracts. These results suggest that caveolin-1 critically contributes to tPA-mediated MMP-9 up-regulation, but may not facilitate MMP-9 secretion in endothelial cells. Thrombolysis with tissue plasminogen activator (tPA) increases matrix metalloproteinase-9 (MMP-9) activity in the ischemic brain, which exacerbates ischemic blood brain barrier (BBB) injury and increases the risk of symptomatic cerebral hemorrhage. Our results suggest a novel mechanism underlying this tPA-MMP 9 axis. In response to tPA treatment, caveolin-1 protein levels increased in endothelial cells, which mediate MMP-9 mRNA up-regulation and its secretion into extracellular space. Caveolin-1 may, however, not facilitate MMP-9 secretion in endothelial cells. Our data suggest caveolin-1 as a novel therapeutic target for protecting the BBB against ischemic damage. The schematic outlines tPA-induced MMP-9 upreguation.

  13. Caveolin-1 mediates tissue plasminogen activator-induced MMP-9 up-regulation in cultured brain microvascular endothelial cells.

    PubMed

    Jin, Xinchun; Sun, Yanyun; Xu, Ji; Liu, Wenlan

    2015-03-01

    Thrombolysis with tissue plasminogen activator (tPA) increases matrix metalloproteinase-9 (MMP-9) activity in the ischemic brain, which exacerbates blood-brain barrier injury and increases the risk of symptomatic cerebral hemorrhage. The mechanism through which tPA enhances MMP-9 activity is not well understood. Here we report an important role of caveolin-1 in mediating tPA-induced MMP-9 synthesis. Brain microvascular endothelial cell line bEnd3 cells were incubated with 5 or 20 μg/ml tPA for 24 hrs before analyzing MMP-9 levels in the conditioned media and cellular extracts by gelatin zymography. tPA at a dose of 20 μg/mL tPA, but not 5 μg/mL, significantly increased MMP-9 level in cultured media while decreasing it in cellular extracts. Concurrently, tPA treatment induced a 2.3-fold increase of caveolin-1 protein levels in endothelial cells. Interestingly, knockdown of Cav-1 with siRNA inhibited tPA-induced MMP-9 mRNA up-regulation and MMP-9 increase in the conditioned media, but did not affect MMP-9 decrease in cellular extracts. These results suggest that caveolin-1 critically contributes to tPA-mediated MMP-9 up-regulation, but may not facilitate MMP-9 secretion in endothelial cells. Thrombolysis with tissue plasminogen activator (tPA) increases matrix metalloproteinase-9 (MMP-9) activity in the ischemic brain, which exacerbates ischemic blood brain barrier (BBB) injury and increases the risk of symptomatic cerebral hemorrhage. Our results suggest a novel mechanism underlying this tPA-MMP 9 axis. In response to tPA treatment, caveolin-1 protein levels increased in endothelial cells, which mediate MMP-9 mRNA up-regulation and its secretion into extracellular space. Caveolin-1 may, however, not facilitate MMP-9 secretion in endothelial cells. Our data suggest caveolin-1 as a novel therapeutic target for protecting the BBB against ischemic damage. The schematic outlines tPA-induced MMP-9 upreguation. PMID:25683686

  14. Green tea diet decreases PCB 126-induced oxidative stress in mice by up-regulating antioxidant enzymes.

    PubMed

    Newsome, Bradley J; Petriello, Michael C; Han, Sung Gu; Murphy, Margaret O; Eske, Katryn E; Sunkara, Manjula; Morris, Andrew J; Hennig, Bernhard

    2014-02-01

    Superfund chemicals such as polychlorinated biphenyls pose a serious human health risk due to their environmental persistence and link to multiple diseases. Selective bioactive food components such as flavonoids have been shown to ameliorate PCB toxicity, but primarily in an in vitro setting. Here, we show that mice fed a green tea-enriched diet and subsequently exposed to environmentally relevant doses of coplanar PCB exhibit decreased overall oxidative stress primarily due to the up-regulation of a battery of antioxidant enzymes. C57BL/6 mice were fed a low-fat diet supplemented with green tea extract (GTE) for 12 weeks and exposed to 5 μmol PCB 126/kg mouse weight (1.63 mg/kg-day) on weeks 10, 11 and 12 (total body burden: 4.9 mg/kg). F2-isoprostane and its metabolites, established markers of in vivo oxidative stress, measured in plasma via HPLC-MS/MS exhibited fivefold decreased levels in mice supplemented with GTE and subsequently exposed to PCB compared to animals on a control diet exposed to PCB. Livers were collected and harvested for both messenger RNA and protein analyses, and it was determined that many genes transcriptionally controlled by aryl hydrocarbon receptor and nuclear factor (erythroid-derived 2)-like 2 proteins were up-regulated in PCB-exposed mice fed the green tea-supplemented diet. An increased induction of genes such as SOD1, GSR, NQO1 and GST, key antioxidant enzymes, in these mice (green tea plus PCB) may explain the observed decrease in overall oxidative stress. A diet supplemented with green tea allows for an efficient antioxidant response in the presence of PCB 126, which supports the emerging paradigm that healthful nutrition may be able to bolster and buffer a physiological system against the toxicities of environmental pollutants.

  15. Ampelopsin Improves Insulin Resistance by Activating PPARγ and Subsequently Up-Regulating FGF21-AMPK Signaling Pathway

    PubMed Central

    Qin, Yu; Liu, Lei; Wan, Jing; Zou, Lingyun; Zhang, Qianyong; Zhu, Jundong; Mi, Mantian

    2016-01-01

    Ampelopsin (APL), a major bioactive constituent of Ampelopsis grossedentata, exerts a number of biological effects. Here, we explored the anti-diabetic activity of APL and elucidate the underlying mechanism of this action. In palmitate-induced insulin resistance of L6 myotubes, APL treatment markedly up- regulated phosphorylated insulin receptor substrate-1 and protein kinase B, along with a corresponding increase of glucose uptake capacity. APL treatment also increased expressions of fibroblast growth factor (FGF21) and phosphorylated adenosine 5’-monophosphate -activated protein kinase (p-AMPK), however inhibiting AMPK by Compound C or AMPK siRNA, or blockage of FGF21 by FGF21 siRNA, obviously weakened APL -induced increases of FGF21 and p-AMPK as well as glucose uptake capacity in palmitate -pretreated L6 myotubes. Furthermore, APL could activate PPAR γ resulting in increases of glucose uptake capacity and expressions of FGF21 and p-AMPK in palmitate -pretreated L6 myotubes, whereas all those effects were obviously abolished by addition of GW9662, a specific inhibitor of peroxisome proliferator- activated receptor –γ (PPARγ), and PPARγsiRNA. Using molecular modeling and the luciferase reporter assays, we observed that APL could dock with the catalytic domain of PPARγ and dose-dependently up-regulate PPARγ activity. In summary, APL maybe a potential agonist of PPARγ and promotes insulin sensitization by activating PPARγ and subsequently regulating FGF21- AMPK signaling pathway. These results provide new insights into the protective health effects of APL, especially for the treatment of Type 2 diabetes mellitus. PMID:27391974

  16. Immunomodulatory drugs act as inhibitors of DNA methyltransferases and induce PU.1 up-regulation in myeloma cells.

    PubMed

    Endo, Shinya; Amano, Masayuki; Nishimura, Nao; Ueno, Niina; Ueno, Shikiko; Yuki, Hiromichi; Fujiwara, Shiho; Wada, Naoko; Hirata, Shinya; Hata, Hiroyuki; Mitsuya, Hiroaki; Okuno, Yutaka

    2016-01-01

    Immunomodulatory drugs (IMiDs) such as thalidomide, lenalidomide, and pomalidomide are efficacious in the treatment of multiple myeloma and significantly prolong their survival. However, the mechanisms of such effects of IMiDs have not been fully elucidated. Recently, cereblon has been identified as a target binding protein of thalidomide. Lenalidomide-resistant myeloma cell lines often lose the expression of cereblon, suggesting that IMiDs act as an anti-myeloma agent through interacting with cereblon. Cereblon binds to damaged DNA-binding protein and functions as a ubiquitin ligase, inducing degradation of IKZF1 and IKZF3 that are essential transcription factors for B and T cell development. Degradation of both IKZF1 and IKZF3 reportedly suppresses myeloma cell growth. Here, we found that IMiDs act as inhibitors of DNA methyltransferases (DMNTs). We previously reported that PU.1, which is an ETS family transcription factor and essential for myeloid and lymphoid development, functions as a tumor suppressor in myeloma cells. PU.1 induces growth arrest and apoptosis of myeloma cell lines. In this study, we found that low-dose lenalidomide and pomalidomide up-regulate PU.1 expression through inducing demethylation of the PU.1 promoter. In addition, IMiDs inhibited DNMT1, DNMT3a, and DNMT3b activities in vitro. Furthermore, lenalidomide and pomalidomide decreased the methylation status of the whole genome in myeloma cells. Collectively, IMiDs exert demethylation activity through inhibiting DNMT1, 3a, and 3b, and up-regulating PU.1 expression, which may be one of the mechanisms of the anti-myeloma activity of IMiDs.

  17. Translocon-associated protein TRAP delta and a novel TRAP-like protein are coordinately expressed with pro-opiomelanocortin in Xenopus intermediate pituitary.

    PubMed

    Holthuis, J C; van Riel, M C; Martens, G J

    1995-11-15

    In the intermediate pituitary gland of Xenopus laevis, the expression levels of the prohormone pro-opiomelanocortin (POMC) can be readily manipulated. When the animal is placed on a black background, the gene for POMC is actively transcribed, whereas on a white background the gene is virtually inactive. In this study, we characterized two genes whose transcript levels in the intermediate pituitary are regulated in coordination with that for POMC. One of these codes for a protein homologous to translocon-associated protein TRAP delta, a subunit of a transmembrane protein complex located at the site where nascent secretory proteins enter the endoplasmic reticulum (ER). Both Xenopus and mice were found to express an alternatively spliced transcript that gives rise to a previously unknown version of the TRAP delta protein. The product of the second gene is a novel and highly conserved protein with structural similarity to glycoprotein gp25L, a constituent of another translocon-associated protein complex. A database search revealed the existence of a novel family of gp25L-related proteins whose members occur throughout the animal kingdom. Together, our data imply that (i) the group of ER proteins surrounding translocating polypeptide chains may be far more complex than previously expected, and (ii) a number of the accessory components of the translocon participate in early steps of prohormone biosynthesis.

  18. P2Y2 nucleotide receptor activation up-regulates vascular cell adhesion molecule-1 [corrected] expression and enhances lymphocyte adherence to a human submandibular gland cell line.

    PubMed

    Baker, Olga J; Camden, Jean M; Rome, Danny E; Seye, Cheikh I; Weisman, Gary A

    2008-01-01

    Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disease that causes salivary and lacrimal gland tissue destruction resulting in impaired secretory function. Although lymphocytic infiltration of salivary epithelium is associated with SS, the mechanisms involved have not been adequately elucidated. Our previous studies have shown that the G protein-coupled P2Y2 nucleotide receptor (P2Y2R) is up-regulated in response to damage or stress of salivary gland epithelium, and in salivary glands of the NOD.B10 mouse model of SS-like autoimmune exocrinopathy. Additionally, we have shown that P2Y2R activation up-regulates vascular cell adhesion molecule-1 (VCAM-1) expression in endothelial cells leading to the binding of monocytes. The present study demonstrates that activation of the P2Y2R in dispersed cell aggregates from rat submandibular gland (SMG) and in human submandibular gland ductal cells (HSG) up-regulates the expression of VCAM-1. Furthermore, P2Y2R activation mediated the up-regulation of VCAM-1 expression in HSG cells leading to increased adherence of lymphocytic cells. Inhibitors of EGFR phosphorylation and metalloprotease activity abolished P2Y2R-mediated VCAM-1 expression and decreased lymphocyte binding to HSG cells. Moreover, silencing of EGFR expression abolished UTP-induced VCAM-1 up-regulation in HSG cells. These results suggest that P2Y2R activation in salivary gland cells increases the EGFR-dependent expression of VCAM-1 and the binding of lymphocytes, a pathway relevant to inflammation associated with SS.

  19. P2Y2 Nucleotide Receptor Activation Up-regulates Vascular Cell Adhesion Molecular-1 Expression and Enhances Lymphocyte Adherence to a Human Submandibular Gland Cell Line

    PubMed Central

    Baker, Olga J.; Camden, Jean M.; Rome, Danny E.; Seye, Cheikh I.; Weisman, Gary A.

    2007-01-01

    Sjögren’s syndrome (SS) is a chronic inflammatory autoimmune disease that causes salivary and lacrimal gland tissue destruction resulting in impaired secretory function. Although lymphocytic infiltration of salivary epithelium is associated with SS, the mechanisms involved have not been adequately elucidated. Our previous studies have shown that the G protein-coupled P2Y2 nucleotide receptor (P2Y2R) is up-regulated in response to damage or stress of salivary gland epithelium, and in salivary glands of the NOD.B10 mouse model of SS-like autoimmune exocrinopathy. Additionally, we have shown that P2Y2R activation up-regulates vascular cell adhesion molecule-1 (VCAM-1) expression in endothelial cells leading to the binding of monocytes. The present study demonstrates that activation of the P2Y2R in dispersed cell aggregates from rat submandibular gland (SMG) and in human submandibular gland ductal cells (HSG) up-regulates the expression of VCAM-1. Furthermore, P2Y2R activation mediated the up-regulation of VCAM-1 expression in HSG cells leading to increased adherence of lymphocytic cells. Inhibitors of EGFR phosphorylation and metalloprotease activity abolished P2Y2R-mediated VCAM-1 expression and decreased lymphocyte binding to HSG cells. Moreover, silencing of EGFR expression abolished UTP-induced VCAM-1 up-regulation in HSG cells. These results suggest that P2Y2R activation in salivary gland cells increases the EGFR-dependent expression of VCAM-1 and the binding of lymphocytes, a pathway relevant to inflammation associated with SS. PMID:17599409

  20. Cinnamon and its Components Suppress Vascular Smooth Muscle Cell Proliferation by Up-Regulating Cyclin-Dependent Kinase Inhibitors.

    PubMed

    Kwon, Hyeeun; Lee, Jung-Jin; Lee, Ji-Hye; Cho, Won-Kyung; Gu, Min Jung; Lee, Kwang Jin; Ma, Jin Yeul

    2015-01-01

    Cinnamomum cassia bark has been used in traditional herbal medicine to treat a variety of cardiovascular diseases. However, the antiproliferative effect of cinnamon extract on vascular smooth muscle cells (VSMCs) and the corresponding restenosis has not been explored. Hence, after examining the effect of cinnamon extract on VSMC proliferation, we investigated the possible involvement of signal transduction pathways associated with early signal and cell cycle analysis, including regulatory proteins. Besides, to identify the active components, we investigated the components of cinnamon extract on VSMC proliferation. Cinnamon extract inhibited platelet-derived growth factor (PDGF)-BB-induced VSMC proliferation and suppressed the PDGF-stimulated early signal transduction. In addition, cinnamon extract arrested the cell cycle and inhibited positive regulatory proteins. Correspondingly, the protein levels of p21 and p27 not only were increased in the presence of cinnamon extract, also the expression of proliferating cell nuclear antigen (PCNA) was inhibited by cinnamon extract. Besides, among the components of cinnamon extract, cinnamic acid (CA), eugenol (EG) and cinnamyl alcohol significantly inhibited the VSMC proliferation. Overall, the present study demonstrates that cinnamon extract inhibited the PDGF-BB-induced proliferation of VSMCs through a G0/G1 arrest, which down-regulated the expression of cell cycle positive regulatory proteins by up-regulating p21 and p27 expression.

  1. HSP70 increases extracellular matrix production by human vascular smooth muscle through TGF-β1 up-regulation.

    PubMed

    González-Ramos, Marta; Calleros, Laura; López-Ongil, Susana; Raoch, Viviana; Griera, Mercedes; Rodríguez-Puyol, Manuel; de Frutos, Sergio; Rodríguez-Puyol, Diego

    2013-02-01

    The circulating levels of heat shock proteins (HSP) are increased in cardiovascular diseases; however, the implication of this for the fibrotic process typical of such diseases remains unclear. HSP70 can interact with the vascular smooth muscle cells (SMC), the major producer of extracellular matrix (ECM) proteins, through the Toll-like receptors 4 (TLR4). The transforming growth factor type-β1 (TGF-β1) is a well known vascular pro-fibrotic cytokine that is regulated in part by AP-1-dependent transcriptional mechanisms. We hypothesized that extracellular HSP70 could interact with SMCs, inducing TGF-β1 synthesis and subsequent changes in the vascular ECM. We demonstrate that extracellular HSP70 binds to human aorta SMC TLR4, which up-regulates the AP-1-dependent transcriptional activity of the TGF-β1 promoter. This is achieved through the mitogen activated protein kinases JNK and ERK, as demonstrated by the use of specific blockers and the knockdown of TLR4 with specific small interfering RNAs. The TGF-β1 upregulation increase the expression of the ECM proteins type I collagen and fibronectin. This novel observation may elucidate the mechanisms by which HSP70 contributes in the inflammation and fibrosis present in atherosclerosis and other fibrosis-related diseases.

  2. HSP70 increases extracellular matrix production by human vascular smooth muscle through TGF-β1 up-regulation.

    PubMed

    González-Ramos, Marta; Calleros, Laura; López-Ongil, Susana; Raoch, Viviana; Griera, Mercedes; Rodríguez-Puyol, Manuel; de Frutos, Sergio; Rodríguez-Puyol, Diego

    2013-02-01

    The circulating levels of heat shock proteins (HSP) are increased in cardiovascular diseases; however, the implication of this for the fibrotic process typical of such diseases remains unclear. HSP70 can interact with the vascular smooth muscle cells (SMC), the major producer of extracellular matrix (ECM) proteins, through the Toll-like receptors 4 (TLR4). The transforming growth factor type-β1 (TGF-β1) is a well known vascular pro-fibrotic cytokine that is regulated in part by AP-1-dependent transcriptional mechanisms. We hypothesized that extracellular HSP70 could interact with SMCs, inducing TGF-β1 synthesis and subsequent changes in the vascular ECM. We demonstrate that extracellular HSP70 binds to human aorta SMC TLR4, which up-regulates the AP-1-dependent transcriptional activity of the TGF-β1 promoter. This is achieved through the mitogen activated protein kinases JNK and ERK, as demonstrated by the use of specific blockers and the knockdown of TLR4 with specific small interfering RNAs. The TGF-β1 upregulation increase the expression of the ECM proteins type I collagen and fibronectin. This novel observation may elucidate the mechanisms by which HSP70 contributes in the inflammation and fibrosis present in atherosclerosis and other fibrosis-related diseases. PMID:23084979

  3. Transient up-regulation of a novel member of Spot 14 family in androgen-stimulated rat prostate.

    PubMed

    Nishi, Nozomu; Shoji, Hiroki; Miyanaka, Hiroshi; Nakamura, Takanori

    2008-01-01

    The rat prostate is dependent on androgen for growth and differentiation. In an effort to find novel genes involved in androgen-induced growth of the rat prostate, we carried out PCR-based subtractive hybridization and identified several factors that were transiently up-regulated after androgen stimulation in castrated rat prostate. Among them, a novel member of the Spot 14 family has been identified. This protein (Spot 14-like androgen-inducible protein, SLAP) exhibited the highest homology (about 50%) with zebrafish gastrulation-specific G12 protein and about 30% homology with rat Spot 14. The SLAP mRNA level decreased following castration and transiently increased after testosterone replacement, attaining a peak 3 days after the treatment. The change in the protein level was similar to that in mRNA except that it was low in both untreated and castrated rat prostate tissue. In normal adult rats, SLAP was expressed at relatively high levels in the lung, stomach and liver. Unlike the prostate, SLAP expression in the lung was not affected by the androgen status. Like other members of the Spot 14 family, SLAP has a leucine-zipper motif in its C-terminal region, making it possible to form a stable homodimer. Though the physiological role of SLAP remains to be clarified, the current results suggest that SLAP expression is associated with some growth-related processes in regrowing rat prostate.

  4. Up-regulation of cyclooxygenase-2 by product-prostaglandin E2

    NASA Technical Reports Server (NTRS)

    Tjandrawinata, R. R.; Hughes-Fulford, M.

    1997-01-01

    The development of prostate cancer has been linked to high level of dietary fat intake. Our laboratory investigates the connection between cancer cell growth and fatty acid products. Studying human prostatic carcinoma PC-3 cells, we found that prostaglandin E2 (PGE2) increased cell growth and up-regulated the gene expression of its own synthesizing enzyme, cyclooxygenase-2 (COX-2). PGE2 increased COX-2 mRNA expression dose-dependently with the highest levels of stimulation seen at the 3-hour period following PGE2 addition. The NSAID flurbiprofen (5 microM), in the presence of exogenous PGE2, inhibited the up-regulation of COX-2 mRNA and cell growth. These data suggest that the levels of local intracellular PGE2 play a major role in the growth of prostate cancer cells through an activation of COX-2 gene expression.

  5. Coordinated protein and DNA remodeling by human HLTF on stalled replication fork.

    PubMed

    Achar, Yathish Jagadheesh; Balogh, David; Haracska, Lajos

    2011-08-23

    Human helicase-like transcription factor (HLTF) exhibits ubiquitin ligase activity for proliferating cell nuclear antigen (PCNA) polyubiquitylation as well as double-stranded DNA translocase activity for remodeling stalled replication fork by fork reversal, which can support damage bypass by template switching. However, a stalled replication fork is surrounded by various DNA-binding proteins which can inhibit the access of damage bypass players, and it is unknown how these proteins become displaced. Here we reveal that HLTF has an ATP hydrolysis-dependent protein remodeling activity, by which it can remove proteins bound to the replication fork. Moreover, we demonstrate that HLTF can displace a broad spectrum of proteins such as replication protein A (RPA), PCNA, and replication factor C (RFC), thereby providing the first example for a protein clearing activity at the stalled replication fork. Our findings clarify how remodeling of a stalled replication fork can occur if it is engaged in interactions with masses of proteins.

  6. Selective CB2 up-regulation in women affected by endometrial inflammation

    PubMed Central

    Iuvone, Teresa; De Filippis, Daniele; Di Spiezio Sardo, Attilio; D'Amico, Alessandra; Simonetti, Sara; Sparice, Stefania; Esposito, Giuseppe; Bifulco, Giuseppe; Insabato, Luigi; Nappi, Carmine; Guida, Maurizio

    2008-01-01

    Abstract Endometritis is defined as an inflammation of the endometrial mucosa of the uterus. In endometritis large amounts of toxic mediators, including nitric oxide (NO) are released by inflammatory cells. As a consequence of nitric oxide-dependent injury, the cells respond by triggering protective mechanisms, by changing the endo-cannabinoid system (ECS) which comprises both CB1 and CB2 cannabinoid receptors and their endogenous ligands. The aim of our study was to seek out evidence for the presence of cannabinoid receptors in inflammatory endometrial tissue as well as for their potential role in endometrial inflammation. Our results showed a selective up-regulation of both transcription and expression of CB2 receptors in biopsies from women affected by endometrial inflammation compared to healthy women. The experiments with the nitric oxide-donor S-Nitroso-L-Glutathione (GSNO) suggest that such a selective up-regulation may be related to the nitric oxide release occurring during endometrial inflammation. In addition, we demonstrated an increase in chymase expression, a marker of mast cells, in biopsies of women affected by endometritis. Therefore our results support the hypothesis that the up-regulation of CB2 occurs mainly on mast cells and that it might tend to sensitize these cells to the anti-inflammatory effect exerted by endogenous cannabinoids by binding their receptor and thus preventing the mast cell degranulation and the release of pro-inflammatory mediators. In conclusion, we believe that the selective CB2 up-regulation might play a role as a novel prognostic factor in endometrial inflammation. PMID:18419603

  7. Rapid systemic up-regulation of genes after heat-wounding and electrical stimulation

    NASA Technical Reports Server (NTRS)

    Davies, E.; Vian, A.; Vian, C.; Stankovic, B.

    1997-01-01

    When one leaf of a tomato plant is electrically-stimulated or heat-wounded, proteinase inhibitor genes are rapidly up-regulated in distant leaves. The identity of the systemic wound signal(s) is not yet known, but major candidates include hormones transmitted via the phloem or the xylem, the electrically-stimulated self-propagating electrical signal in the phloem (the action potential, AP), or the heat-wound-induced surge in hydraulic pressure in the xylem evoking a local change in membrane potential in adjacent living cells (the variation potential, VP). In order to discriminate between these signals we have adopted two approaches. The first approach involves applying stimuli that evoke known signals and determining whether these signals have similar effects on the "model" transcripts for proteinase inhibitors (pin) and calmodulin (cal). Here we show that a heat wound almost invariably evokes a VP, while an electrical stimulation occasionally evokes an AP, and both of these signals induce accumulation of transcripts encoding proteinase inhibitors. The second approach involves identifying the array of genes turned on by heat-wounding. To this end, we have constructed a subtractive library for heat-wounded tissue, isolated over 800 putatively up-regulated clones, and shown that all but two of the fifty that we have analyzed by Northern hybridization are, indeed, up-regulated. Here we show the early kinetics of up-regulation of three of these transcripts in the terminal (4th) leaf in response to heat-wounding the 3rd leaf, about 5 cm away. Even though these transcripts show somewhat different time courses of induction, with one peaking at 30 min, another at 15 min, and another at 5 min after flaming of a distant leaf, they all exhibit a similar pattern, i.e., a transient period of transcript accumulation preceding a period of transcript decrease, followed by a second period of transcript accumulation.

  8. HO-1 up-regulation: a key point in high-risk neuroblastoma resistance to bortezomib.

    PubMed

    Furfaro, Anna Lisa; Piras, Sabrina; Passalacqua, Mario; Domenicotti, Cinzia; Parodi, Alessia; Fenoglio, Daniela; Pronzato, Maria Adelaide; Marinari, Umberto Maria; Moretta, Lorenzo; Traverso, Nicola; Nitti, Mariapaola

    2014-04-01

    High-risk neuroblastoma (NB) is characterized by the development of chemoresistance, and bortezomib (BTZ), a selective inhibitor of proteasome, has been proposed in order to overcome drug resistance. Considering the involvement of the nuclear factor-erythroid-derived 2-like 2 (Nrf2) and heme oxygenase-1 (HO-1) in the antioxidant and detoxifying ability of cancer cells, in this study we have investigated their role in differently aggressive NB cell lines treated with BTZ, focusing on the modulation of HO-1 to improve sensitivity to therapy. We have shown that MYCN amplified HTLA-230 cells were slightly sensitive to BTZ treatment, due to the activation of Nrf2 that led to an impressive up-regulation of HO-1. BTZ-treated HTLA-230 cells down-regulated p53 and up-regulated p21, favoring cell survival. The inhibition of HO-1 activity obtained by Zinc (II) protoprophyrin IX (ZnPPIX) was able to significantly increase the pro-apoptotic effect of BTZ in a p53- and p21-independent way. However, MYCN non-amplified SH-SY5Y cells showed a greater sensitivity to BTZ in relation to their inability to up-regulate HO-1. Therefore, we have shown that HO-1 inhibition improves the sensitivity of aggressive NB to proteasome inhibition-based therapy, suggesting that HO-1 up-regulation can be used as a marker of chemoresistance in NB. These results open up a new scenario in developing a combined therapy to overcome chemoresistance in high-risk neuroblastoma.

  9. "Anion clamp" allows flexible protein to impose coordination geometry on metal ions.

    PubMed

    Wang, Minji; Lai, Tsz Pui; Wang, Li; Zhang, Hongmin; Yang, Nan; Sadler, Peter J; Sun, Hongzhe

    2015-05-01

    X-ray crystal structures of human serum transferrin (77 kDa) with Yb(III) or Fe(III) bound to the C-lobe and malonate as the synergistic anion show that the large Yb(III) ion causes the expansion of the metal binding pocket while octahedral metal coordination geometry is preserved, an unusual geometry for a lanthanide ion.

  10. Identification and analysis of Phytophthora cactorum genes up-regulated during cyst germination and strawberry infection.

    PubMed

    Chen, Xiaoren; Klemsdal, Sonja Sletner; Brurberg, May Bente

    2011-10-01

    The oomycete Phytophthora cactorum can cause economically important diseases on numerous host plants worldwide, such as crown rot on strawberry. To explore the molecular mechanisms underlying the pathogenicity of P. cactorum on strawberry, transcriptional analysis of P. cactorum during strawberry infection and cyst germination was performed by applying suppression subtractive hybridization (SSH) and effector-specific differential display (ESDD) techniques. Two SSH cDNA libraries were generated, enriched for P. cactorum genes expressed during infection or during cyst germination, respectively, and 137 unique differentially expressed genes were identified. To specifically select RxLR effector genes from P. cactorum, ESDD was performed using RxLR and EER motif-based degenerate primers. Eight RxLR effector candidate genes as well as 67 other genes were identified out of 124 selected fragments. The expression levels of 20 putatively up-regulated genes were further analyzed using real-time RT-PCR, showing that, indeed 19 of these 20 genes were up-regulated during at least one of the studied developmental stages or during strawberry crown invasion, relative to the mycelium. This study provides a first overview of P. cactorum genes that are up-regulated immediately prior to or during strawberry infection and also provides a novel method for selecting RxLR effector genes from the unsequenced genome of P. cactorum.

  11. Placental fractalkine is up-regulated in severe early onset preeclampsia

    PubMed Central

    Siwetz, Monika; Dieber-Rotheneder, Martina; Cervar-Zivkovic, Mila; Kummer, Daniel; Kremshofer, Julia; Weiss, Gregor; Herse, Florian; Huppertz, Berthold; Gauster, Martin

    2015-01-01

    The pathogenesis of preeclampsia includes the release of placental factors into the maternal circulation inducing an inflammatory environment in the mother. One of the factors may be the pro-inflammatory chemokine fractalkine, which is expressed in the syncytiotrophoblast of human placenta, from where it is released into the maternal circulation by constitutive shedding. We examined whether placental fractalkine is up-regulated in severe early onset preeclampsia and whether the pro-inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin-6 are able to increase the expression of fractalkine. Gene expression analysis, ELISA, and immunohistochemistry consistently showed increased fractalkine expression in placentas from severe early onset preeclampsia, compared to gestational age-matched controls. Expression of the metalloproteinases ADAM10 and ADAM17, which convert transmembrane fractalkine into the soluble form, was significantly increased in these cases. Incubation of first trimester placental explants with TNF-α provoked a significant increase in fractalkine expression and release of the soluble form, whereas interleukin-6 had no effect. TNF-α-mediated up-regulation of placental fractalkine was reversed in the presence of the Aspirin-derivative salicylate, which impaired activation of NF-κB p65 in TNF-α-treated explants. Based on data from placental explants we suggest that increased maternal TNF-α may up-regulate the expression and release of placental fractalkine, which in turn may contribute to an exaggerated systemic inflammatory response in preeclampsia. PMID:25769431

  12. Placental fractalkine is up-regulated in severe early-onset preeclampsia.

    PubMed

    Siwetz, Monika; Dieber-Rotheneder, Martina; Cervar-Zivkovic, Mila; Kummer, Daniel; Kremshofer, Julia; Weiss, Gregor; Herse, Florian; Huppertz, Berthold; Gauster, Martin

    2015-05-01

    The pathogenesis of preeclampsia (PE) includes the release of placental factors into the maternal circulation, inducing an inflammatory environment in the mother. One of the factors may be the proinflammatory chemokine fractalkine, which is expressed in the syncytiotrophoblast of human placenta, from where it is released into the maternal circulation by constitutive shedding. We examined whether placental fractalkine is up-regulated in severe early-onset PE and whether the proinflammatory cytokines tumor necrosis factor (TNF)-α and IL-6 are able to increase the expression of fractalkine. Gene expression analysis, enzyme-linked immunosorbent assay, and immunohistochemistry consistently showed increased fractalkine expression in placentas from severe early-onset PE, compared to gestational age-matched controls. Expression of a disintegrin and metalloproteinases (ADAMs) 10 and 17, which convert transmembrane fractalkine into the soluble form, was significantly increased in these cases. Incubation of first-trimester placental explants with TNF-α provoked a significant increase in fractalkine expression and release of the soluble form, whereas IL-6 had no effect. TNF-α-mediated up-regulation of placental fractalkine was reversed in the presence of the aspirin-derivative salicylate, which impaired activation of NF-κB p65 in TNF-α-treated explants. On the basis of data from placental explants, we suggest that increased maternal TNF-α may up-regulate the expression and release of placental fractalkine, which, in turn, may contribute to an exaggerated systemic inflammatory response in PE. PMID:25769431

  13. Iron-induced Local Complement Component 3 (C3) Up-regulation via Non-canonical Transforming Growth Factor (TGF)-β Signaling in the Retinal Pigment Epithelium*

    PubMed Central

    Li, Yafeng; Song, Delu; Song, Ying; Zhao, Liangliang; Wolkow, Natalie; Tobias, John W.; Song, Wenchao; Dunaief, Joshua L.

    2015-01-01

    Dysregulation of iron homeostasis may be a pathogenic factor in age-related macular degeneration (AMD). Meanwhile, the formation of complement-containing deposits under the retinal pigment epithelial (RPE) cell layer is a pathognomonic feature of AMD. In this study, we investigated the molecular mechanisms by which complement component 3 (C3), a central protein in the complement cascade, is up-regulated by iron in RPE cells. Modulation of TGF-β signaling, involving ERK1/2, SMAD3, and CCAAT/enhancer-binding protein-δ, is responsible for iron-induced C3 expression. The differential effects of spatially distinct SMAD3 phosphorylation sites at the linker region and at the C terminus determined the up-regulation of C3. Pharmacologic inhibition of either ERK1/2 or SMAD3 phosphorylation decreased iron-induced C3 expression levels. Knockdown of SMAD3 blocked the iron-induced up-regulation and nuclear accumulation of CCAAT/enhancer-binding protein-δ, a transcription factor that has been shown previously to bind the basic leucine zipper 1 domain in the C3 promoter. We show herein that mutation of this domain reduced iron-induced C3 promoter activity. In vivo studies support our in vitro finding of iron-induced C3 up-regulation. Mice with a mosaic pattern of RPE-specific iron overload demonstrated co-localization of iron-induced ferritin and C3d deposits. Humans with aceruloplasminemia causing RPE iron overload had increased RPE C3d deposition. The molecular events in the iron-C3 pathway represent therapeutic targets for AMD or other diseases exacerbated by iron-induced local complement dysregulation. PMID:25802332

  14. Up-regulation of eEF1A2 promotes proliferation and inhibits apoptosis in prostate cancer

    SciTech Connect

    Sun, Yue; Du, Chengli; Wang, Bo; Zhang, Yanling; Liu, Xiaoyan; Ren, Guoping

    2014-07-18

    Highlights: • The expression of eEF1A2 is up-regulated in prostate cancer tissues. • Suppression of eEF1A2 inhibits the proliferation and promotes apoptosis. • Inhibition of eEF1A2 enhances the expression of apoptotic relevant proteins. • The expressions of eEF1A2 and cleavage-caspase3 are inversely correlated. - Abstract: Background: eEF1A2 is a protein translation factor involved in protein synthesis, which possesses important function roles in cancer development. This study aims at investigating the expression pattern of eEF1A2 in prostate cancer and its potential role in prostate cancer development. Methods: We examined the expression level of eEF1A2 in 30 pairs of prostate cancer tissues by using RT-PCR and immunohistochemical staining (IHC). Then we applied siRNA specifically targeting eEF1A2 to down-regulate its expression in DU-145 and PC-3 cells. Flow cytometer was used to explore apoptosis and Western-blot was used to detect the pathway proteins of apoptosis. Results: Our results showed that the expression level of eEF1A2 in prostate cancer tissues was significantly higher compared to their corresponding normal tissues. Reduction of eEF1A2 expression in DU-145 and PC-3 cells led to a dramatic inhibition of proliferation accompanied with enhanced apoptosis rate. Western blot revealed that apoptosis pathway proteins (caspase3, BAD, BAX, PUMA) were significantly up-regulated after suppression of eEF1A2. More importantly, the levels of eEF1A2 and caspase3 were inversely correlated in prostate cancer tissues. Conclusion: Our data suggests that eEF1A2 plays an important role in prostate cancer development, especially in inhibiting apoptosis. So eEF1A2 might serve as a potential therapeutic target in prostate cancer.

  15. Up-Regulation of miR-21 Is Associated with Cervicitis and Human Papillomavirus Infection in Cervical Tissues

    PubMed Central

    Bumrungthai, Sureewan; Ekalaksananan, Tipaya; Evans, Mark Francis; Chopjitt, Peechanika; Tangsiriwatthana, Thumwadee; Patarapadungkit, Natcha; Kleebkaow, Pilaiwan; Luanratanakorn, Sanguanchoke; Kongyingyoes, Bunkerd; Worawichawong, Suchin; Pientong, Chamsai

    2015-01-01

    MicroRNA-21 (miR-21) is recognized as an oncomir and shows up-regulation in many types of human malignancy. The aim of this study was to investigate the association of miR-21 expression associated with HPV infection in normal and abnormal cervical tissues. Cervical tissue samples with different cytological or histopathological grades were investigated for HPV by PCR and for miR-21 and programmed cell death, protein 4 (PDCD4) expression using quantitative real-time PCR (qRT-PCR). Laser capture microdissection (LCM) of stromal and epithelial tissues and in situ hybridization (ISH) using locked nucleic acid (LNA) probes were performed on a subset of fixed specimens. Cell line experiments were conducted on fibroblasts stimulated in culture media from HeLa cells, which were then assessed for miR-21, PDCD4, IL-6 and α-SMA expression by qRT-PCR. Twenty normal cervical cell, 12 cervicitis, 14 cervical intraepithelial neoplastic I (CIN I), 22 CIN II-III and 43 cervical squamous cell carcinoma (SCC) specimens were investigated. miR-21 levels were significantly lower in normal than in abnormal tissues. The expression of miR-21 in HPV negative normal cytology was significantly lower than in HPV positive samples in abnormal tissue and SCC. The miR-21 expression was significantly higher in HPV negative cervicitis than HPV negative normal cells. LCM and ISH data showed that miR-21 is primarily expressed in the tumor-associated stromal cell microenvironment. Fibroblasts treated with HeLa cell culture media showed up-regulated expression of miR-21, which correlated with increased expression of α-SMA and IL-6 and with down-regulation of PDCD4. These results demonstrate that miR-21 is associated with HPV infection and involved in cervical lesions as well as cervicitis and its up-regulation in tumor-stroma might be involved in the inflammation process and cervical cancer progression. PMID:26010154

  16. Exposure to diesel exhaust up-regulates iNOS expression in ApoE knockout mice

    SciTech Connect

    Bai Ni; Kido, Takashi; Kavanagh, Terrance J.; Kaufman, Joel D.; Rosenfeld, Michael E.; Breemen, Cornelis van; Eeden, Stephan F. van

    2011-09-01

    blood vessels and heart. > DE exposure enhanced iNOS protein and mRNA expression in the aorta and heart. > iNOS activity was also increased after DE exposure. > This up-regulation of iNOS may contribute to vascular dysfunction and atherogenesis.

  17. Rapamycin regulates the proliferation of Huh7, a hepatocellular carcinoma cell line, by up-regulating p53 expression.

    PubMed

    Kwon, Sora; Jeon, Ji-Sook; Ahn, Curie; Sung, Jung-Suk; Choi, Inho

    2016-10-01

    Rapamycin, a specific inhibitor of mTOR used extensively as an immunosuppressant, has been expanded recently to cancer therapy, because the mTOR signal is known to be up-regulated in various cancer cells including hepatocellular carcinoma (HCC) cells. In spite of extensive efforts to employ mTOR inhibitors as anti-HCC therapy, they have not yet been approved by the FDA. Because of the heterogeneity and complexity of molecular signaling in HCC, suitable biomarkers should be identified or discovered to improve clinical efficacy of mTOR-specific inhibitors to HCC cells. In this study, the effect of rapamycin was investigated on two different HCC cell lines, Huh7 cells and HepG2 cells. Rapamycin was found to inhibit the proliferation of Huh7 cells but not of HepG2 cells. Moreover, it was found that rapamycin can up-regulate p53 at the protein level, but not affect its transcript. To understand the critical role of p53 in the rapamycin effect, knock-down experiments were performed using small-interfering RNAs (siRNAs). The anti-proliferative effect of rapamycin on Huh7 cells clearly disappeared after blocking p53 production with siRNA, which indicates that p53 is a critical factor in the anti-proliferative effect of rapamycin in HCC cells. The over-expression system of p53 was also employed to mimic the effect of rapamycin and found that cell proliferation was clearly down-regulated by p53 over-expression. Finally, we found that the extracellular signal-regulated kinase 1/2 (ERK1/2) signal was regulated by p53 whose expression was induced by rapamycin. Overall, this study demonstrates that rapamycin inhibited the proliferation of Huh7 cells by up-regulating the expression of p53 and down-regulating the ERK1/2 signal, indicating that p53 is a useful biomarker for anti-cancer therapy using the specific inhibitor of mTOR signal, rapamycin, against hepatocellular carcinoma cells.

  18. Interleukin-1 beta-induced up-regulation of opioid receptors in the untreated and morphine-desensitized U87 MG human astrocytoma cells

    PubMed Central

    2012-01-01

    Background Interleukin-1beta (IL-1β) is a pro-inflammatory cytokine that can be produced in the central nervous system during inflammatory conditions. We have previously shown that IL-1β expression is altered in the rat brain during a morphine tolerant state, indicating that this cytokine may serve as a convergent point between the immune challenge and opiate mediated biological pathways. We hypothesized that IL-1β up-regulates opioid receptors in human astrocytes in both untreated and morphine-desensitized states. Methods To test this hypothesis, we compared the basal expression of the mu (MOR), delta (DOR), and kappa (KOR) opioid receptors in the human U87 MG astrocytic cell line to SH-SY5Y neuronal and HL-60 immune cells using absolute quantitative real time RT-PCR (AQ-rt-RT-PCR). To demonstrate that IL-1β induced up-regulation of the MOR, DOR and KOR, U87 MG cells (2 x 105 cells/well) were treated with IL-1β (20 ng/mL or 40 ng/mL), followed by co-treatment with interleukin-1 receptor antagonist protein (IL-1RAP) (400 ng/mL or 400 ng/mL). The above experiment was repeated in the cells desensitized with morphine, where U87 MG cells were pre-treated with 100 nM morphine. The functionality of the MOR in U87 MG cells was then demonstrated using morphine inhibition of forksolin-induced intracellular cAMP, as determined by radioimmunoassay. Results U87 MG cells treated with IL-1β for 12 h showed a significant up-regulation of MOR and KOR. DOR expression was also elevated, although not significantly. Treatment with IL-1β also showed a significant up-regulation of the MOR in U87 MG cells desensitized with morphine. Co-treatment with IL-1β and interleukin-1 receptor antagonist protein (IL-1RAP) resulted in a significant decrease in IL-1β-mediated MOR up-regulation. Conclusion Our results indicate that the pro-inflammatory cytokine, IL-1β, affects opiate-dependent pathways by up-regulating the expression of the MOR in both untreated and morphine-desensitized U87

  19. Direct interaction of CaVβ with actin up-regulates L-type calcium currents in HL-1 cardiomyocytes.

    PubMed

    Stölting, Gabriel; de Oliveira, Regina Campos; Guzman, Raul E; Miranda-Laferte, Erick; Conrad, Rachel; Jordan, Nadine; Schmidt, Silke; Hendriks, Johnny; Gensch, Thomas; Hidalgo, Patricia

    2015-02-20

    Expression of the β-subunit (CaVβ) is required for normal function of cardiac L-type calcium channels, and its up-regulation is associated with heart failure. CaVβ binds to the α1 pore-forming subunit of L-type channels and augments calcium current density by facilitating channel opening and increasing the number of channels in the plasma membrane, by a poorly understood mechanism. Actin, a key component of the intracellular trafficking machinery, interacts with Src homology 3 domains in different proteins. Although CaVβ encompasses a highly conserved Src homology 3 domain, association with actin has not yet been explored. Here, using co-sedimentation assays and FRET experiments, we uncover a direct interaction between CaVβ and actin filaments. Consistently, single-molecule localization analysis reveals streaklike structures composed by CaVβ2 that distribute over several micrometers along actin filaments in HL-1 cardiomyocytes. Overexpression of CaVβ2-N3 in HL-1 cells induces an increase in L-type current without altering voltage-dependent activation, thus reflecting an increased number of channels in the plasma membrane. CaVβ mediated L-type up-regulation, and CaVβ-actin association is prevented by disruption of the actin cytoskeleton with cytochalasin D. Our study reveals for the first time an interacting partner of CaVβ that is directly involved in vesicular trafficking. We propose a model in which CaVβ promotes anterograde trafficking of the L-type channels by anchoring them to actin filaments in their itinerary to the plasma membrane.

  20. Direct Interaction of CaVβ with Actin Up-regulates L-type Calcium Currents in HL-1 Cardiomyocytes*

    PubMed Central

    Stölting, Gabriel; de Oliveira, Regina Campos; Guzman, Raul E.; Miranda-Laferte, Erick; Conrad, Rachel; Jordan, Nadine; Schmidt, Silke; Hendriks, Johnny; Gensch, Thomas; Hidalgo, Patricia

    2015-01-01

    Expression of the β-subunit (CaVβ) is required for normal function of cardiac L-type calcium channels, and its up-regulation is associated with heart failure. CaVβ binds to the α1 pore-forming subunit of L-type channels and augments calcium current density by facilitating channel opening and increasing the number of channels in the plasma membrane, by a poorly understood mechanism. Actin, a key component of the intracellular trafficking machinery, interacts with Src homology 3 domains in different proteins. Although CaVβ encompasses a highly conserved Src homology 3 domain, association with actin has not yet been explored. Here, using co-sedimentation assays and FRET experiments, we uncover a direct interaction between CaVβ and actin filaments. Consistently, single-molecule localization analysis reveals streaklike structures composed by CaVβ2 that distribute over several micrometers along actin filaments in HL-1 cardiomyocytes. Overexpression of CaVβ2-N3 in HL-1 cells induces an increase in L-type current without altering voltage-dependent activation, thus reflecting an increased number of channels in the plasma membrane. CaVβ mediated L-type up-regulation, and CaVβ-actin association is prevented by disruption of the actin cytoskeleton with cytochalasin D. Our study reveals for the first time an interacting partner of CaVβ that is directly involved in vesicular trafficking. We propose a model in which CaVβ promotes anterograde trafficking of the L-type channels by anchoring them to actin filaments in their itinerary to the plasma membrane. PMID:25533460

  1. Improved myocardial perfusion in chronic diabetic mice by the up-regulation of pLKB1 and AMPK signaling.

    PubMed

    Kusmic, Claudia; L'abbate, Antonio; Sambuceti, Gianmario; Drummond, George; Barsanti, Cristina; Matteucci, Marco; Cao, Jian; Piccolomini, Francesco; Cheng, Jennifer; Abraham, Nader G

    2010-04-01

    Previous studies related impaired myocardial microcirculation in diabetes to oxidative stress and endothelial dysfunction. Thus, this study was aimed to determine the effect of up-regulating pAMPK-pAKT signaling on coronary microvascular reactivity in the isolated heart of diabetic mice. We measured coronary resistance in wild-type and streptozotocin (STZ)-treated mice, during perfusion pressure changes. Glucose, insulin, and adiponectin levels in plasma and superoxide formation, NOx levels and heme oxygenase (HO) activity in myocardial tissue were determined. In addition, the expression of HO-1, 3-nitrotyrosine, pLKB1, pAMPK, pAKT, and peNOS proteins in control and diabetic hearts were measured. Coronary response to changes in perfusion pressure diverged from control in a time-dependent manner following STZ administration. The responses observed at 28 weeks of diabetes (the maximum time examined) were mimicked by L-NAME administration to control animals and were associated with a decrease in serum adiponectin and myocardial pLKB1, pAMPK, pAKT, and pGSK-3 expression. Cobalt protoporphyrin treatment to induce HO-1 expression reversed the microvascular reactivity seen in diabetes towards that of controls. Up-regulation of HO-1 was associated with an increase in adiponectin, pLKB1, pAKT, pAMPK, pGSK-3, and peNOS levels and a decrease in myocardial superoxide and 3-nitrotyrosine levels. In the present study we describe the time course of microvascular functional changes during the development of diabetes and the existence of a unique relationship between the levels of serum adiponectin, pLKB1, pAKT, and pAMPK activation in diabetic hearts. The restoration of microvascular function suggests a new therapeutic approach to even advanced cardiac microvascular derangement in diabetes.

  2. Uterine Expression of NDRG4 Is Induced by Estrogen and Up-Regulated during Embryo Implantation Process in Mice

    PubMed Central

    Zhang, Xuan; Wang, Jian-Mei; He, Ya-Ping; Shi, Yan; Sun, Zhao-Gui; Shi, Hui-Juan; Wang, Jian

    2016-01-01

    Embryo implantation is an essential step for the establishment of pregnancy and dynamically regulated by estrogen and progesterone. NDRG4 (N-myc down-regulated gene 4) is a tumor suppressor that participates in cell survival, tumor invasion and angiogenesis. The objective of this study was to preliminarily explore the role of NDRG4 in embryo implantation. By immunohistochemistry (IHC) and quantitive RT-PCR (qRT-PCR), we found that uterine expression of NDRG4 was increased along with puberal development, and its expression in adult females reached the peak at the estrus stage during the estrus cycle. Furthermore, uterine NDRG4 expression was significantly induced by the treatment of estradiol (E2) both in pre-puberty females and ovariectomized adult females. Uterine expression pattern of NDRG4 during the peri-implantation period in mice was determined by IHC, qRT-PCR and Western blot. It was observed that NDRG4 expression was up-regulated during the implantation process, and its expression level at the implantation sites was significantly higher than that at the inter-implantation sites. Meanwhile, an increased expression in NDRG4 was associated with artificial decidualization as well as the activation of delayed implantation. By qRT-PCR and Western blot, we found that the in vitro decidualization of endometrial stromal cells (ESCs) was accompanied by up-regulation of NDRG4 expression, whereas knockdown of its expression in these cells by siRNA inhibited the decidualization process. In addition, Western blot analysis showed that NDRG4 protein expression was decreased in human villus tissues of recurrent miscarriage (RM) patients compared to normal pregnant women. Collectively, these data suggested that uterine NDRG4 expression could be induced by estrogen, and NDRG4 might play an important role during early pregnancy. PMID:27175791

  3. Up-regulation of C1GALT1 promotes breast cancer cell growth through MUC1-C signaling pathway

    PubMed Central

    Chou, Chih-Hsing; Huang, Miao-Juei; Chen, Chi-Hau; Shyu, Ming-Kwang; Huang, John; Hung, Ji-Shiang; Huang, Chiun-Sheng; Huang, Min-Chuan

    2015-01-01

    Aberrant glycosylation is frequently observed in cancers. Core 1 β1,3-galactosyltransferase (C1GALT1) is an exclusive enzyme in humans that catalyzes the biosynthesis of core 1 O-glycan structure, Gal-GalNAc-O-Ser/Thr, whose expression is commonly up-regulated during tumorigenesis. Little is known about the function of C1GALT1 in breast cancer. This study aims to determine the correlation between C1GALT1 expression and breast cancer clinicopathological features and roles of C1GALT1 in breast cancer malignant phenotypes. Public databases and our data showed that C1GALT1 mRNA and C1GALT1 protein are frequently up-regulated in breast cancer; and increased C1GALT1 expression correlates with higher histological grade and advanced tumor stage. Overexpression of C1GALT1 enhanced breast cancer cell growth, migration, and invasion in vitro as well as tumor growth in vivo. Conversely, C1GALT1 knockdown suppressed these malignant phenotypes. Furthermore, C1GALT1 modulates O-glycan structures on Mucin (MUC) 1 and promotes MUC1-C/β-catenin signaling in breast cancer cells. These findings suggest that C1GALT1 enhances breast cancer malignant progression through promoting MUC1-C/β-catenin signaling pathway. Unveiling the function of C1GALT1 in breast cancer opens new insights to the roles of C1GALT1 and O-glycosylation in tumorigenesis and renders the potential of C1GALT1 as a target of novel therapeutic agent development. PMID:25762620

  4. Hypoxic stress up-regulates Kir2.1 expression and facilitates cell proliferation in brain capillary endothelial cells.

    PubMed

    Yamamura, Hideto; Suzuki, Yoshiaki; Yamamura, Hisao; Asai, Kiyofumi; Imaizumi, Yuji

    2016-08-01

    The blood-brain barrier (BBB) is mainly composed of brain capillary endothelial cells (BCECs), astrocytes and pericytes. Brain ischemia causes hypoxic encephalopathy and damages BBB. However, it remains still unclear how hypoxia affects BCECs. In the present study, t-BBEC117 cells, an immortalized bovine brain endothelial cell line, were cultured under hypoxic conditions at 4-5% oxygen for 72 h. This hypoxic stress caused hyperpolarization of resting membrane potential. Patch-clamp recordings revealed a marked increase in Ba(2+)-sensitive inward rectifier K(+) current in t-BBEC117 cells after hypoxic culture. Western blot and real-time PCR analyses showed that Kir2.1 expression was significantly up-regulated at protein level but not at mRNA level after the hypoxic culture. Ca(2+) imaging study revealed that the hypoxic stress enhanced store-operated Ca(2+) (SOC) entry, which was significantly reduced in the presence of 100 μM Ba(2+). On the other hand, the expression of SOC channels such as Orai1, Orai2, and transient receptor potential channels was not affected by hypoxic stress. MTT assay showed that the hypoxic stress significantly enhanced t-BBEC117 cell proliferation, which was inhibited by approximately 60% in the presence of 100 μM Ba(2+). We first show here that moderate cellular stress by cultivation under hypoxic conditions hyperpolarizes membrane potential via the up-regulation of functional Kir2.1 expression and presumably enhances Ca(2+) entry, resulting in the facilitation of BCEC proliferation. These findings suggest potential roles of Kir2.1 expression in functional changes of BCECs in BBB following ischemia. PMID:27235552

  5. Uterine Expression of NDRG4 Is Induced by Estrogen and Up-Regulated during Embryo Implantation Process in Mice.

    PubMed

    Yang, Qian; Gu, Yan; Zhang, Xuan; Wang, Jian-Mei; He, Ya-Ping; Shi, Yan; Sun, Zhao-Gui; Shi, Hui-Juan; Wang, Jian

    2016-01-01

    Embryo implantation is an essential step for the establishment of pregnancy and dynamically regulated by estrogen and progesterone. NDRG4 (N-myc down-regulated gene 4) is a tumor suppressor that participates in cell survival, tumor invasion and angiogenesis. The objective of this study was to preliminarily explore the role of NDRG4 in embryo implantation. By immunohistochemistry (IHC) and quantitive RT-PCR (qRT-PCR), we found that uterine expression of NDRG4 was increased along with puberal development, and its expression in adult females reached the peak at the estrus stage during the estrus cycle. Furthermore, uterine NDRG4 expression was significantly induced by the treatment of estradiol (E2) both in pre-puberty females and ovariectomized adult females. Uterine expression pattern of NDRG4 during the peri-implantation period in mice was determined by IHC, qRT-PCR and Western blot. It was observed that NDRG4 expression was up-regulated during the implantation process, and its expression level at the implantation sites was significantly higher than that at the inter-implantation sites. Meanwhile, an increased expression in NDRG4 was associated with artificial decidualization as well as the activation of delayed implantation. By qRT-PCR and Western blot, we found that the in vitro decidualization of endometrial stromal cells (ESCs) was accompanied by up-regulation of NDRG4 expression, whereas knockdown of its expression in these cells by siRNA inhibited the decidualization process. In addition, Western blot analysis showed that NDRG4 protein expression was decreased in human villus tissues of recurrent miscarriage (RM) patients compared to normal pregnant women. Collectively, these data suggested that uterine NDRG4 expression could be induced by estrogen, and NDRG4 might play an important role during early pregnancy. PMID:27175791

  6. CX3CL1 is up-regulated in the rat hippocampus during memory-associated synaptic plasticity.

    PubMed

    Sheridan, Graham K; Wdowicz, Anita; Pickering, Mark; Watters, Orla; Halley, Paul; O'Sullivan, Niamh C; Mooney, Claire; O'Connell, David J; O'Connor, John J; Murphy, Keith J

    2014-01-01

    Several cytokines and chemokines are now known to play normal physiological roles in the brain where they act as key regulators of communication between neurons, glia, and microglia. In particular, cytokines and chemokines can affect cardinal cellular and molecular processes of hippocampal-dependent long-term memory consolidation including synaptic plasticity, synaptic scaling and neurogenesis. The chemokine, CX3CL1 (fractalkine), has been shown to modulate synaptic transmission and long-term potentiation (LTP) in the CA1 pyramidal cell layer of the hippocampus. Here, we confirm widespread expression of CX3CL1 on mature neurons in the adult rat hippocampus. We report an up-regulation in CX3CL1 protein expression in the CA1, CA3 and dentate gyrus (DG) of the rat hippocampus 2 h after spatial learning in the water maze task. Moreover, the same temporal increase in CX3CL1 was evident following LTP-inducing theta-burst stimulation in the DG. At physiologically relevant concentrations, CX3CL1 inhibited LTP maintenance in the DG. This attenuation in dentate LTP was lost in the presence of GABAA receptor/chloride channel antagonism. CX3CL1 also had opposing actions on glutamate-mediated rise in intracellular calcium in hippocampal organotypic slice cultures in the presence and absence of GABAA receptor/chloride channel blockade. Using primary dissociated hippocampal cultures, we established that CX3CL1 reduces glutamate-mediated intracellular calcium rises in both neurons and glia in a dose dependent manner. In conclusion, CX3CL1 is up-regulated in the hippocampus during a brief temporal window following spatial learning the purpose of which may be to regulate glutamate-mediated neurotransmission tone. Our data supports a possible role for this chemokine in the protective plasticity process of synaptic scaling. PMID:25161610

  7. Differential screening of mutated SOD1 transgenic mice reveals early up-regulation of a fast axonal transport component in spinal cord motor neurons.

    PubMed

    Dupuis, L; de Tapia, M; René, F; Lutz-Bucher, B; Gordon, J W; Mercken, L; Pradier, L; Loeffler, J P

    2000-08-01

    In the present study we analyze the molecular mechanisms underlying motor neuron degeneration in familial amyotrophic lateral sclerosis (FALS). For this, we used a transgenic mouse model expressing the Cu/Zn superoxide dismutase (SOD1) gene with a Gly(86) to Arg (G86R) mutation equivalent to that found in a subset of human FALS. Using an optimized suppression subtractive hybridization method, a cDNA specifically up-regulated during the asymptomatic phase in the lumbar spinal cord of G86R mice was identified by sequence analysis as the KIF3-associated protein (KAP3), a regulator of fast axonal transport. RT-PCR analysis revealed that KAP3 induction was an early event arising long before axonal degeneration. Immunohistochemical studies further revealed that KAP3 protein predominantly accumulates in large motor neurons of the ventral spinal cord. We further demonstrated that KAP3 up-regulation occurs independent of any change in the other components of the kinesin II complex. However, since the ubiquitous KIF1A motor is up-regulated, our results show an early and complex rearrangement of the fast axonal transport machinery in the course of FALS pathology.

  8. Pancreatic adenocarcinoma up-regulated factor expression is associated with disease-specific survival in cervical cancer patients.

    PubMed

    Choi, Chel Hun; Chung, Joon-Yong; Park, Ho-Seop; Jun, Minsik; Lee, Yoo-Young; Kim, Byung-Gie; Hewitt, Stephen M

    2015-06-01

    Pancreatic adenocarcinoma up-regulated factor (PAUF) is a novel soluble protein involved in tumor development and metastases. This study was to investigate the PAUF expression and its prognostic value in cervical cancer patients. The expression of PAUF was immunohistochemically determined in 345 formalin-fixed, paraffin-embedded cervical cancer tissues and 107 normal cervical epitheliums. Subsequently, its associations with clinicopathological characteristics and patient survival were assessed. PAUF protein was expressed both in cytoplasm and nucleus, and cytoplasmic expression was more frequent in cancers than normal tissues (32% versus 17%, P = .002), and the difference was prominent in glandular cells. Notably, the expression was more frequent in adenocarcinoma than in squamous cell carcinoma (57% versus 25%, respectively; P < .001), and the differential expression was also seen at the messenger RNA level (P = .014). Cox regression analysis showed that the cytoplasmic expression of PAUF protein was independently associated with poor disease-free (hazard ratio = 2.3; 95% confidence interval, 1.2-4.3; P = .008) and overall survival (hazard ratio = 2.9; 95% confidence interval, 1.2-7.5; P = .020). Detection of PAUF expression may aid current evaluation of prognosis in cervical adenocarcinoma.

  9. Lectin purified from Musca domestica pupa up-regulates NO and iNOS production via TLR4/NF-κB signaling pathway in macrophages.

    PubMed

    Cao, Xiaohong; Zhou, Minghui; Wang, Chunling; Hou, Lihua; Zeng, Bin

    2011-04-01

    The present study reported that nitric oxide (NO) was up-regulated by the induction of lectin purified from Musca domestica pupa (MPL) in macrophages without cytotoxicity. The mRNA expression and protein secretion of inducible nitric oxide synthase (iNOS) were strongly induced by MPL treatments. Subsequent investigation revealed that the nuclear factor-κB (NF-κB) inhibitory κB (IκB) in endochylema was inhibited and NF-κB translocated into the nucleus after MPL treatment. Meanwhile, the IKKβ was strongly induced and the production of the toll-like receptor 4 (TLR4) was significantly up-regulated. Moreover, MPL increased NO production via inducing the expression of iNOS through the activation of NF-κB, which suggested that MPL probably acted as an activating agent of the NF-κB activation.

  10. The neuroprotection of hypoxic preconditioning on rat brain against traumatic brain injury by up-regulated transcription factor Nrf2 and HO-1 expression.

    PubMed

    Shu, Longfei; Wang, Chunlin; Wang, Jinbiao; Zhang, Yongming; Zhang, Xing; Yang, Yanyan; Zhuo, Jianwei; Liu, Jiachuan

    2016-01-12

    Hypoxic preconditioning (HPC) increases the inherent tolerance of brain tissue suffering from severe hypoxia or ischemia insult by stimulating the protective ability of the brain. However, little is known concerning the effect of HPC on traumatic brain injury (TBI). We designed this study to investigate the effect of HPC on TBI and explore its underlying mechanisms. We found that HPC significantly alleviates neurological dysfunction, lessens brain edema, reduces cell apoptosis, increases neuronal survival, up-regulates the expressions of Nrf2 and HO-1, and decreases the inducer of protein carbonyls, 4-hydroxy-2-nonenal, and 8-hydroxy-2-deoxyguanosine in the brain tissue of rats 24h after brain injury. However, no influence was observed in normal rats after only 3d of hypoxic training. Results further indicated that HPC protects the brain against traumatic damage. This protective effect may be achieved by up-regulating Nrf2 and HO-1 expression and alleviating oxidative stress damage. PMID:26590328

  11. Quantitative Glycoproteomic Analysis Identifies Platelet-Induced Increase of Monocyte Adhesion via the Up-Regulation of Very Late Antigen 5.

    PubMed

    Huang, Jiqing; Kast, Juergen

    2015-08-01

    Physiological stimuli, such as thrombin, or pathological stimuli, such as lysophosphatidic acid (LPA), activate platelets circulating in blood. Once activated, platelets bind to monocytes via P-selectin-PSGL-1 interactions but also release the stored contents of their granules. These platelet releasates, in addition to direct platelet binding, activate monocytes and facilitate their recruitment to atherosclerotic sites. Consequently, understanding the changes platelet releasates induce in monocyte membrane proteins is critical. We studied the glyco-proteome changes of THP-1 monocytic cells affected by LPA- or thrombin-induced platelet releasates. We employed lectin affinity chromatography combined with filter aided sample preparation to achieve high glyco- and membrane protein and protein sequence coverage. Using stable isotope labeling by amino acids in cell culture, we quantified 1715 proteins, including 852 membrane and 500 glycoproteins, identifying the up-regulation of multiple proteins involved in monocyte extracellular matrix binding and transendothelial migration. Flow cytometry indicated expression changes of integrin α5, integrin β1, PECAM-1, and PSGL-1. The observed increase in monocyte adhesion to fibronectin was determined to be mediated by the up-regulation of very late antigen 5 via a P-selectin-PSGL-1 independent mechanism. This novel aspect could be validated on CD14+ human primary monocytes, highlighting the benefits of the improved enrichment method regarding high membrane protein coverage and reliable quantification. PMID:26159767

  12. Predicting protein backbone chemical shifts from Cα coordinates: extracting high resolution experimental observables from low resolution models.

    PubMed

    Frank, Aaron T; Law, Sean M; Ahlstrom, Logan S; Brooks, Charles L

    2015-01-13

    Given the demonstrated utility of coarse-grained modeling and simulations approaches in studying protein structure and dynamics, developing methods that allow experimental observables to be directly recovered from coarse-grained models is of great importance. In this work, we develop one such method that enables protein backbone chemical shifts (1HN, 1Hα, 13Cα, 13C, 13Cβ, and 15N) to be predicted from Cα coordinates. We show that our Cα-based method, LARMORCα, predicts backbone chemical shifts with comparable accuracy to some all-atom approaches. More importantly, we demonstrate that LARMORCα predicted chemical shifts are able to resolve native structure from decoy pools that contain both native and non-native models, and so it is sensitive to protein structure. As an application, we use LARMORCα to characterize the transient state of the fast-folding protein gpW using recently published NMR relaxation dispersion derived backbone chemical shifts. The model we obtain is consistent with the previously proposed model based on independent analysis of the chemical shift dispersion pattern of the transient state. We anticipate that LARMORCα will find utility as a tool that enables important protein conformational substates to be identified by “parsing” trajectories and ensembles generated using coarse-grained modeling and simulations.

  13. N-acetylcysteine inhibits the up-regulation of mitochondrial biogenesis genes in livers from rats fed ethanol chronically

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Chronic ethanol (EtOH) administration to experimental animals induces hepatic oxidative stress and up-regulates mitochondrial biogenesis. The mechanisms by which chronic EtOH up-regulates mitochondrial biogenesis have not been fully explored. In this work, we hypothesized that oxidative ...

  14. Mutations in BALB Mitochondrial DNA Induce CCL20 Up-regulation Promoting Tumorigenic Phenotypes

    PubMed Central

    Sligh, James; Janda, Jaroslav; Jandova, Jana

    2014-01-01

    mtDNA mutations are common in human cancers and are thought to contribute to the process of neoplasia. We examined the role of mtDNA mutations in skin cancer by generating fibroblast cybrids harboring a mutation in the gene encoding the mitochondrial tRNA for arginine. This somatic mutation (9821insA) was previously reported in UV-induced hyperkeratotic skin tumors in hairless mice and confers specific tumorigenic phenotypes to mutant cybrids. Microarray analysis revealed and RT-PCR along with Western blot analysis confirmed the up-regulation of CCL20 and its receptor CCR6 in mtBALB haplotype containing the mt-Tr 9821insA allele compared to wild type mtB6 haplotype. Based on reported role of CCL20 in cancer progression we examined whether the hyper-proliferation and enhanced motility of mtBALB haplotype would be associated with CCL20 levels. Treatment of both genotypes with recombinant CCL20 (rmCCL20) resulted in enhanced growth and motility of mtB6 cybrids. Furthermore, the acquired somatic alteration increased the in vivo tumor growth of mtBALB cybrids through the up-regulation of CCL20 since neutralizing antibody significantly decreased in vivo tumor growth of these cells; and tumors from anti-CCL20 treated mice injected with mtBALB cybrids showed significantly decreased CCL20 levels. When rmCCL20 or mtBALB cybrids were used as chemotactic stimuli, mtB6 cybrids showed increased motility while anti-CCL20 antibody decreased the migration and in vivo tumor growth of mtBALB cybrids. Moreover, the inhibitors of MAPK signaling and NF-κB activation inhibited CCL20 expression in mtBALB cybrids and decreased their migratory capabilities. Thus, acquired mtDNA mutations may promote tumorigenic phenotypes through up-regulation of chemokine CCL20. PMID:25177208

  15. Urban air pollution produces up-regulation of myocardial inflammatory genes and dark chocolate provides cardioprotection.

    PubMed

    Villarreal-Calderon, Rodolfo; Reed, William; Palacios-Moreno, Juan; Keefe, Sheyla; Herritt, Lou; Brooks, Diane; Torres-Jardón, Ricardo; Calderón-Garcidueñas, Lilian

    2012-05-01

    Air pollution is a serious environmental problem. Elderly subjects show increased cardiac morbidity and mortality associated with air pollution exposure. Mexico City (MC) residents are chronically exposed to high concentrations of fine particulate matter (PM(2.5)) and PM-associated lipopolysaccharides (PM-LPS). To test the hypothesis that chronic exposure to urban pollution produces myocardial inflammation, female Balb-c mice age 4 weeks were exposed for 16 months to two distinctly different polluted areas within MC: southwest (SW) and northwest (NW). SW mice were given either no treatment or chocolate 2g/9.5 mg polyphenols/3 times per week. Results were compared to mice kept in clean air. Key inflammatory mediator genes: cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), and the LPS receptor CD14 (cluster of differentiation antigen 14) were measured by real-time polymerase chain reaction. Also explored were target NFκB (nuclear factor κB), oxidative stress and antioxidant defense genes. TNF-α, IL-6, and COX-2 were significantly increased in both NW and SWMC mice (p=0.0001). CD14 was up-regulated in SW mice in keeping with the high exposures to particulate matter associated endotoxin. Chocolate administration resulted in a significant down-regulation of TNF-α (p<0.0001), IL-6 (p=0.01), and IL-1β (p=0.02). The up-regulation of antioxidant enzymes and the down-regulation of potent oxidases, toll-like receptors, and pro-apoptotic signaling genes completed the protective profile. Exposure to air pollution produces up-regulation of inflammatory myocardial genes and endotoxin plays a key role in the inflammatory response. Regular consumption of dark chocolate may reduce myocardial inflammation and have cardioprotective properties in the setting of air pollution exposures. PMID:20932730

  16. Up-regulation of nicotinic acetylcholine receptors in menthol cigarette smokers

    PubMed Central

    Brody, Arthur L; Mukhin, Alexey G; La Charite, Jaime; Ta, Karen; Farahi, Judah; Sugar, Catherine A.; Mamoun, Michael S.; Vellios, Evan; Archie, Meena; Kozman, Maggie; Phuong, Jonathan; Arlorio, Franca; Mandelkern, Mark A.

    2013-01-01

    One-third of smokers primarily use menthol cigarettes and usage of these cigarettes leads to elevated serum nicotine levels and more difficulty quitting in standard treatment programmes. Previous brain imaging studies demonstrate that smoking (without regard to cigarette type) leads to up-regulation of β2*-containing nicotinic acetylcholine receptors (nAChRs). We sought to determine if menthol cigarette usage results in greater nAChR up-regulation than non-menthol cigarette usage. Altogether, 114 participants (22 menthol cigarette smokers, 41 non-menthol cigarette smokers and 51 non-smokers) underwent positron emission tomography scanning using the α4β2* nAChR radioligand 2-[18F]fluoro-A-85380 (2-FA). In comparing menthol to non-menthol cigarette smokers, an overall test of 2-FA total volume of distribution values revealed a significant between-group difference, resulting from menthol smokers having 9–28% higher α4β2* nAChR densities than non-menthol smokers across regions. In comparing the entire group of smokers to non-smokers, an overall test revealed a significant between-group difference, resulting from smokers having higher α4β2* nAChR levels in all regions studied (36–42%) other than thalamus (3%). Study results demonstrate that menthol smokers have greater up-regulation of nAChRs than non-menthol smokers. This difference is presumably related to higher nicotine exposure in menthol smokers, although other mechanisms for menthol influencing receptor density are possible. These results provide additional information about the severity of menthol cigarette use and may help explain why these smokers have more trouble quitting in standard treatment programmes. PMID:23171716

  17. Agonist- and antagonist-induced up-regulation of surface 5-HT3A receptors

    PubMed Central

    Morton, Russell A; Baptista-Hon, Daniel T; Hales, Tim G; Lovinger, David M

    2015-01-01

    Background and Purpose The 5-HT3 receptor is a member of the pentameric ligand-gated ion channel family and is pharmacologically targeted to treat irritable bowel syndrome and nausea/emesis. Furthermore, many antidepressants elevate extracellular concentrations of 5-HT. This study investigates the functional consequences of exposure of recombinant 5-HT3A receptors to agonists and antagonists. Experimental Approach We used HEK cells stably expressing recombinant 5-HT3A receptors and the ND7/23 (mouse neuroblastoma/dorsal root ganglion hybrid) cell line, which expresses endogenous 5-HT3 receptors. Surface expression of recombinant 5-HT3A receptors, modified to contain the bungarotoxin (BTX) binding sequence, was quantified using fluorescence microscopy to image BTX-conjugated fluorophores. Whole cell voltage-clamp electrophysiology was used to measure the density of current mediated by 5-HT3A receptors. Key Results 5-HT3A receptors were up-regulated by the prolonged presence of agonists (5-HT and m-chlorophenylbiguanide) and antagonists (MDL-72222 and morphine). The up-regulation of 5-HT3A receptors by 5-HT and MDL-72222 was time- and concentration-dependent but was independent of newly translated receptors. The phenomenon was observed for recombinant rodent and human 5-HT3A receptors and for endogenous 5-HT3 receptors in neuronal ND7/23 cells. Conclusions and Implications Up-regulation of 5-HT3A receptors, following exposure to either agonists or antagonists suggests that this phenomenon may occur in response to different therapeutic agents. Medications that elevate 5-HT levels, such as the antidepressant inhibitors of 5-HT reuptake and antiemetic inhibitors of 5-HT3 receptor function, may both raise receptor expression. However, this will require further investigation in vivo. PMID:25989383

  18. Urban Air Pollution Produces Up-Regulation of Myocardial Inflammatory Genes and Dark Chocolate Provides Cardioprotection

    PubMed Central

    Villarreal-Calderon, Rodolfo; Reed, William; Palacios-Moreno, Juan; Keefe, Sheyla; Herritt, Lou; Brooks, Diane; Torres-Jardón, Ricardo; Calderón-Garcidueñas, Lilian

    2010-01-01

    Air pollution is a serious environmental problem. Elderly subjects show increased cardiac morbidity and mortality associated with air pollution exposure. Mexico City (MC) residents are chronically exposed to high concentrations of fine particulate matter (PM2.5) and PM-associated lipopolysaccharides (PM-LPS). To test the hypothesis that chronic exposure to urban pollution produces myocardial inflammation, female Balb-c mice age 4 weeks were exposed for 16 months to two distinctly different polluted areas within MC: Southwest (SW) and Northwest (NW). SW mice were given either no treatment or chocolate 2g/9.5 mg polyphenols/3 times per week. Results were compared to mice kept in clean air. Key inflammatory mediator genes: cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), and the LPS receptor CD14 (cluster of differentiation antigen 14) were measured by real time polymerase chain reaction. Also explored were target NFκB (Nuclear Factor κ B), oxidative stress and antioxidant defense genes. TNF-α, IL-6, and COX-2 were significantly increased in both NW and SWMC mice (p=0.0001). CD14 was up-regulated in SW mice in keeping with the high exposures to particulate matter associated endotoxin. Chocolate administration resulted in a significant down-regulation of TNF-α (p<0.0001), IL-6 (p=0.01), and IL-1β (p=0.02). The up-regulation of antioxidant enzymes and the down-regulation of potent oxidases, toll-like receptors, and pro-apoptotic signaling genes completed the protective profile. Exposure to air pollution produces up-regulation of inflammatory myocardial genes and endotoxin plays a key role in the inflammatory response. Regular consumption of dark chocolate may reduce myocardial inflammation and have cardioprotective properties in the setting of air pollution exposures. PMID:20932730

  19. The Natural Antimicrobial Enzyme Lysozyme is Up-Regulated in Gastrointestinal Inflammatory Conditions.

    PubMed

    Rubio, Carlos A

    2014-01-01

    The cells that line the mucosa of the human gastrointestinal tract (GI, that is, oral cavity, oesophagus, stomach, small intestine, large intestine, and rectum) are constantly challenged by adverse micro-environmental factors, such as different pH, enzymes, and bacterial flora. With exception of the oral cavity, these microenvironments also contain remnant cocktails of secreted enzymes and bacteria from upper organs along the tract. The density of the GI bacteria varies, from 103/mL near the gastric outlet, to 1010/mL at the ileocecal valve, to 1011 to 1012/mL in the colon. The total microbial population (ca. 1014) exceeds the total number of cells in the tract. It is, therefore, remarkable that despite the prima facie inauspicious mixture of harmful secretions and bacteria, the normal GI mucosa retains a healthy state of cell renewal. To counteract the hostile microenvironment, the GI epithelia react by speeding cell exfoliation (the GI mucosa has a turnover time of two to three days), by increasing peristalsis, by eliminating bacteria through secretion of plasma cell-immunoglobulins and by increasing production of natural antibacterial compounds, such as defensin-5 and lysozyme. Only recently, lysozyme was found up-regulated in Barrett's oesophagitis, chronic gastritis, gluten-induced atrophic duodenitis (coeliac disease), collagenous colitis, lymphocytic colitis, and Crohn's colitis. This up-regulation is a response directed to the special types of bacteria recently detected in these diseases. The aim of lysozyme up-regulation is to protect individual mucosal segments to chronic inflammation. The molecular mechanisms connected to the crosstalk between the intraluminal bacterial flora and the production of lysozyme released by the GI mucosae, are discussed. Bacterial resistance continues to exhaust our supply of commercial antibiotics. The potential use of lysozyme to treat infectious diseases is receiving much attention. PMID:25437608

  20. Up-regulation of the adrenomedullin system mediates hypotension and hypoaldosteronism induced by simulated microgravity.

    PubMed

    Andreis, Paola G; Rossi, Gian Paolo; Bova, Sergio; Neri, Giuliano; Nussdorfer, Gastone G; Mazzocchi, Giuseppina

    2004-04-01

    We recently demonstrated that prolonged simulated microgravity (SMG) induced hypotension and hypoaldosteronism in rats, and gathered preliminary evidence for an involvement of circulating adrenomedullin (AM). Thus, we aimed to investigate whether short-term SMG elicits the same effects, and whether up-regulation of adrenal AM system plays a relevant role. Rats were exposed for 8 days to SMG in the form of hindlimb unweighting, and then, along with control animals, were given an intraperitoneal injection of AM22-52 and/or angiotensin-II (Ang-II) (100 nmoles/kg) or the saline vehicle. Systolic blood pressure (SBP) was measured by tail-cuff sphygmomanometry. The adrenal expression of AM was assayed by semiquantitative RT-PCR. The plasma concentrations of aldosterone (PAC) and AM, and adrenal AM content were measured by RIA. Short-term SMG induced significant decreases in SBP and PAC. Conversely, both the plasma and adrenal levels of AM, and adrenal AM mRNA were enhanced in SMG-exposed animals. The SMG-induced hypotension and hypoaldosteronism were reversed by AM22-52, an AM-receptor antagonist, thereby demonstrating a causal link between these effects and the up-regulation of AM system. SMG hampered SBP and PAC responses to Ang-II; the co-administration of AM22-52 restored these responses. These findings accord well with the known ability of AM to counteract the effects of Ang-II on both blood vessels and adrenocortical cells. Taken together, our findings allow us to conclude that up-regulation of the adrenal AM system i) occurs early and takes part in the adaptative changes occurring during SMG conditions; and ii) may account for both hypotension and hypoaldosteronism on returning to the normogravitational environment.

  1. Nicotine induces chromatin changes and c-Jun up-regulation in HL-60 leukemia cells.

    PubMed

    Landais, Emilie; El-Khoury, Victoria; Prevost, Alain; Dufer, Jean; Liautaud-Roger, Françoise

    2005-12-01

    Although nicotine has been implicated as a potential factor in the pathogenesis of human cancer, its mechanisms of action regarding cancer development remain largely unknown. HL-60 cells were used to investigate the effects of a short-term treatment with nicotine at concentrations found in the blood of smokers. The findings show that nicotine induces chromatin decondensation, histone H3 acetylation and up-regulation of the c-Jun transcription factor mRNA. This increase is inhibited by mecamylamine, a nicotinic receptor antagonist, suggesting that nicotine alters cellular function directly via nicotinic acetylcholine receptors and may then play a role in cell physiology and tumor promotion.

  2. Inhibition of the ERK phosphorylation plays a role in terbinafine-induced p21 up-regulation and DNA synthesis inhibition in human vascular endothelial cells

    SciTech Connect

    Ho, P.-Y.; Hsu, S.-P.; Liang, Y.-C.; Kuo, M.-L.; Ho, Y.-S.; Lee, W.-S.

    2008-05-15

    Previously, we showed that terbinafine (TB) induces cell-cycle arrest in cultured human umbilical vein endothelial cells (HUVEC) through an up-regulation of the p21 protein. The aim of this study is to delineate the molecular mechanisms underlying TB-induced increase of p21 protein. RT-PCR analysis demonstrated that the mRNA levels of p21 and p53 were increased in the TB-treated HUVEC. The p21 promoter activity was also increased by TB treatment. Transfection of HUVEC with p53 dominant negative (DN) abolished the TB-induced increases of p21 promoter activity and protein level, suggesting that the TB-induced increase of p21 is p53-dependent. Western blot analysis demonstrated that TB decreased the levels of phosphorylated extracellular signal-regulated kinase (ERK). Over-expression of mitogen-activated protein kinase (MEK)-1, the immediate upstream activator kinase of ERK, abolished the TB-induced increases of p21 and p53 protein and decrease of thymidine incorporation. The ERK inhibitor (PD98059) enhanced the TB-induced inhibition of thymidine incorporation into HUVEC. Taken together, these data suggest that the decrease of ERK activity plays a role in the TB-induced up-regulation of p21 in HUVEC. On the other hand, pretreatment of the cells with geranylgeraniol (GGOH), farnesol (FOH), or Ras inhibitor peptide did not affect the TB-induced decrease of thymidine incorporation. Taken together, our results suggest that TB might cause a decrease of MEK, which in turn up-regulates p53 through the inhibition of ERK phosphorylation, and finally causes an increase of p21 expression and cell-cycle arrest.

  3. Mitochondria-Translocated PGK1 Functions as a Protein Kinase to Coordinate Glycolysis and the TCA Cycle in Tumorigenesis.

    PubMed

    Li, Xinjian; Jiang, Yuhui; Meisenhelder, Jill; Yang, Weiwei; Hawke, David H; Zheng, Yanhua; Xia, Yan; Aldape, Kenneth; He, Jie; Hunter, Tony; Wang, Liwei; Lu, Zhimin

    2016-03-01

    It is unclear how the Warburg effect that exemplifies enhanced glycolysis in the cytosol is coordinated with suppressed mitochondrial pyruvate metabolism. We demonstrate here that hypoxia, EGFR activation, and expression of K-Ras G12V and B-Raf V600E induce mitochondrial translocation of phosphoglycerate kinase 1 (PGK1); this is mediated by ERK-dependent PGK1 S203 phosphorylation and subsequent PIN1-mediated cis-trans isomerization. Mitochondrial PGK1 acts as a protein kinase to phosphorylate pyruvate dehydrogenase kinase 1 (PDHK1) at T338, which activates PDHK1 to phosphorylate and inhibit the pyruvate dehydrogenase (PDH) complex. This reduces mitochondrial pyruvate utilization, suppresses reactive oxygen species production, increases lactate production, and promotes brain tumorigenesis. Furthermore, PGK1 S203 and PDHK1 T338 phosphorylation levels correlate with PDH S293 inactivating phosphorylation levels and poor prognosis in glioblastoma patients. This work highlights that PGK1 acts as a protein kinase in coordinating glycolysis and the tricarboxylic acid (TCA) cycle, which is instrumental in cancer metabolism and tumorigenesis.

  4. Mitochondria-translocated phosphoglycerate kinase 1 functions as a protein kinase to coordinate glycolysis and TCA cycle in tumorigenesis

    PubMed Central

    Li, Xinjian; Jiang, Yuhui; Meisenhelder, Jill; Yang, Weiwei; Hawke, David H.; Zheng, Yanhua; Xia, Yan; Aldape, Kenneth; He, Jie; Hunter, Tony; Wang, Liwei; Lu, Zhimin

    2016-01-01

    SUMMARY It is unclear how the Warburg effect that exemplifies enhanced glycolysis in the cytosol is coordinated with suppressed mitochondrial pyruvate metabolism. We demonstrate here that hypoxia, EGFR activation, and expression of K-Ras G12V and B-Raf V600E induce mitochondrial translocation of phosphoglycerate kinase 1 (PGK1); this is mediated by ERK-dependent PGK1 S203 phosphorylation and subsequent PIN1-mediated cis–trans isomerization. Mitochondrial PGK1 acts as a protein kinase to phosphorylate pyruvate dehydrogenase kinase 1 (PDHK1) at T338, which activates PDHK1 to phosphorylate and inhibit the pyruvate dehydrogenase (PDH) complex. This reduces mitochondrial pyruvate utilization, suppresses reactive oxygen species production, increases lactate production, and promotes brain tumorigenesis. Furthermore, PGK1 S203 and PDHK1 T338 phosphorylation levels correlate with PDH S293 inactivating phosphorylation levels and poor prognosis in glioblastoma patients. This work highlights that PGK1 act as a protein kinase in coordinating glycolysis and the TCA cycle, which is instrumental in cancer metabolism and tumorigenesis. PMID:26942675

  5. Tax-interacting protein 1 coordinates the spatiotemporal activation of Rho GTPases and regulates the infiltrative growth of human glioblastoma

    PubMed Central

    Wang, Hailun; Han, Miaojun; Whetsell, William; Wang, Jialiang; Rich, Jeremy; Hallahan, Dennis; Han, Zhaozhong

    2014-01-01

    PDZ domains represent one group of the major structural units that mediate protein interactions in intercellular contact, signal transduction and assembly of biological machineries. TIP-1 protein is composed of a single PDZ domain that distinguishes TIP-1 from other PDZ domain proteins that more often contain multiple protein domains and function as scaffolds for protein complex assembly. However, the biological functions of TIP-1, especially in cell transformation and tumor progression, are still controversial as observed in a variety of cell types. In this study, we have identified ARHGEF7, a guanine nucleotide exchange factor (GEF) for Rho GTPases, as one novel TIP-1 interacting protein in human glioblastoma cells. We found that the presence of TIP-1 protein is essential to the intracellular redistribution of ARHGEF7 and rhotekin, one Rho effector, and the spatiotemporally coordinated activation of Rho GTPases (RhoA, Cdc42 and Rac1) in migrating glioblastoma cells. TIP-1 knockdown resulted in both aberrant localization of ARHGEF7 and rhotekin, as well as abnormal activation of Rho GTPases that was accompanied with impaired motility of glioblastoma cells. Furthermore, TIP-1 knockdown suppressed tumor cell dispersal in orthotopic glioblastoma murine models. We also observed high levels of TIP-1 expression in human glioblastoma specimens, and the elevated TIP-1 levels are associated with advanced staging and poor prognosis in glioma patients. Although more studies are needed to further dissect the mechanism(s) by which TIP-1 modulates the intracellular redistribution and activation of Rho GTPases, this study suggests that TIP-1 holds potential as both a prognostic biomarker and a therapeutic target of malignant gliomas. PMID:23563176

  6. Serpinin: A Novel Chromogranin A-Derived, Secreted Peptide Up-Regulates Protease Nexin-1 Expression and Granule Biogenesis in Endocrine Cells

    PubMed Central

    Koshimizu, Hisatsugu; Cawley, Niamh X.; Kim, Taeyoon; Yergey, Alfred L.

    2011-01-01

    Previously we demonstrated that chromogranin A (CgA) promoted secretory granule biogenesis in endocrine cells by stabilizing and preventing granule protein degradation in the Golgi, through up-regulation of expression of the protease inhibitor, protease nexin-1 (PN-1). However, the mechanism by which CgA signals the increase of PN-1 expression is unknown. Here we identified a 2.9-kDa CgA-C-terminus peptide, which we named serpinin, in conditioned media from AtT-20 cells, a corticotroph cell line, which up-regulated PN-1 mRNA expression. Serpinin was secreted from AtT-20 cells upon high potassium stimulation and increased PN-1 mRNA transcription in these cells, in an actinomycin D-inhibitable manner. CgA itself and other CgA-derived peptides, when added to AtT-20 cell media, had no effect on PN-1 expression. Treatment of AtT-20 cells with 10 nm serpinin elevated cAMP levels and PN-1 mRNA expression, and this effect was inhibited by a protein kinase A inhibitor, 6–22 amide. Serpinin and a cAMP analog, 8-bromo-cAMP, promoted the translocation of the transcription factor Sp1 into the nucleus, which is known to drive PN-1 expression. Additionally, an Sp1 inhibitor, mithramycin A inhibited the serpinin-induced PN-1 mRNA up-regulation. Furthermore, a luciferase reporter assay demonstrated serpinin-induced up-regulation of PN-1 promoter activity in an Sp1-dependent manner. When added to CgB-transfected 6T3 cells, a mutant AtT20 cell line, serpinin induced granule biogenesis as evidenced by the presence of CgB puncta accumulation in the processes and tips. Our findings taken together show that serpinin, a novel CgA-derived peptide, is secreted upon stimulation of corticotrophs and plays an important autocrine role in up-regulating PN-1-dependent granule biogenesis via a cAMP-protein kinase A-Sp1 pathway to replenish released granules. PMID:21436258

  7. Transcript profiling reveals that cysteine protease inhibitors are up-regulated in tuber sprouts after extended darkness.

    PubMed

    Grandellis, Carolina; Giammaria, Veronica; Fantino, Elisa; Cerrudo, Ignacio; Bachmann, Sandra; Santin, Franco; Ulloa, Rita M

    2016-07-01

    Potato (Solanum tuberosum L.) tubers are an excellent staple food due to its high nutritional value. When the tuber reaches physiological competence, sprouting proceeds accompanied by changes at mRNA and protein levels. Potato tubers become a source of carbon and energy until sprouts are capable of independent growth. Transcript profiling of sprouts grown under continuous light or dark conditions was performed using the TIGR 10K EST Solanaceae microarray. The profiles analyzed show a core of highly expressed transcripts that are associated to the reactivation of growth. Under light conditions, the photosynthetic machinery was fully activated; the highest up-regulation was observed for the Rubisco activase (RCA), the glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and the Photosystem II 22 kDa protein (CP22) genes, among others. On the other hand, sprouts exposed to continuous darkness elongate longer, and after extended darkness, synthesis of chloroplast components was repressed, the expression of proteases was reduced while genes encoding cysteine protease inhibitors (CPIs) and metallocarboxypeptidase inhibitors (MPIs) were strongly induced. Northern blot and RT-PCR analysis confirmed that MPI levels correlated with the length of the dark period; however, CPI expression was strong only after longer periods of darkness, suggesting a feedback loop (regulation mechanism) in response to dark-induced senescence. Prevention of cysteine protease activity in etiolated sprouts exposed to extended darkness could delay senescence until they emerge to light.

  8. The long noncoding RNA MALAT1 promotes tumor-driven angiogenesis by up-regulating pro-angiogenic gene expression

    PubMed Central

    Tee, Andrew E.; Liu, Bing; Song, Renhua; Li, Jinyan; Pasquier, Eddy; Cheung, Belamy B.; Jiang, Cizhong; Marshall, Glenn M.; Haber, Michelle; Norris, Murray D.; Fletcher, Jamie I.; Dinger, Marcel E.; Liu, Tao

    2016-01-01

    Neuroblastoma is the most common solid tumor during early childhood. One of the key features of neuroblastoma is extensive tumor-driven angiogenesis due to hypoxia. However, the mechanism through which neuroblastoma cells drive angiogenesis is poorly understood. Here we show that the long noncoding RNA MALAT1 was upregulated in human neuroblastoma cell lines under hypoxic conditions. Conditioned media from neuroblastoma cells transfected with small interfering RNAs (siRNA) targeting MALAT1, compared with conditioned media from neuroblastoma cells transfected with control siRNAs, induced significantly less endothelial cell migration, invasion and vasculature formation. Microarray-based differential gene expression analysis showed that one of the genes most significantly down-regulated following MALAT1 suppression in human neuroblastoma cells under hypoxic conditions was fibroblast growth factor 2 (FGF2). RT-PCR and immunoblot analyses confirmed that MALAT1 suppression reduced FGF2 expression, and Enzyme-Linked Immunosorbent Assays revealed that transfection with MALAT1 siRNAs reduced FGF2 protein secretion from neuroblastoma cells. Importantly, addition of recombinant FGF2 protein to the cell culture media reversed the effects of MALAT1 siRNA on vasculature formation. Taken together, our data suggest that up-regulation of MALAT1 expression in human neuroblastoma cells under hypoxic conditions increases FGF2 expression and promotes vasculature formation, and therefore plays an important role in tumor-driven angiogenesis. PMID:26848616

  9. Prolonged Starvation Causes Up-Regulation of AQP1 in Adipose Tissue Capillaries of AQP7 Knock-Out Mice.

    PubMed

    Skowronski, Mariusz T; Skowronska, Agnieszka; Rojek, Aleksandra; Oklinski, Michal K; Nielsen, Søren

    2016-01-01

    Aquaporins (AQPs) are membrane proteins involved in the regulation of cellular transport and the balance of water and glycerol and cell volume in the white adipose tissue (WAT). In our previous study, we found the co-expression of the AQP1 water channel and AQP7 in the mouse WAT. In our present study, we aimed to find out whether prolonged starvation influences the AQP1 expression of AQP7 knock-out mice (AQP7 KO) in the WAT. To resolve this hypothesis, immunoperoxidase, immunoblot and immunogold microscopy were used. AQP1 expression was found with the use of immunohistochemistry and was confirmed by immunogold microscopy in the vessels of mouse WAT of all studied groups. Semi-quantitative immunoblot and quantitative immunogold microscopy showed a significant increase (by 2.5- to 3-fold) in the abundance of AQP1 protein expression in WAT in the 72 h starved AQP7 KO mice as compared to AQP7+/+ (p < 0.05) and AQP7-/- (p < 0.01) controls, respectively. In conclusion, the AQP1 water channel located in the vessels of WAT is up-regulated in response to prolonged starvation in the WAT of AQP7 KO mice. The present data suggest that an interaction of different AQP isoforms is required for maintaining proper water homeostasis within the mice WAT. PMID:27455244

  10. Folic acid protects against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1.

    PubMed

    Ma, Yan; Zhang, Chen; Gao, Xiao-Bo; Luo, Hai-Yan; Chen, Yang; Li, Hui-hua; Ma, Xu; Lu, Cai-Ling

    2015-11-05

    As a nutritional factor, folic acid can prevent cardiac and neural defects during embryo development. Our previous study showed that arsenic impairs embryo development by down-regulating Dvr1/GDF1 expression in zebrafish. Here, we investigated whether folic acid could protect against arsenic-mediated embryo toxicity. We found that folic acid supplementation increases hatching and survival rates, decreases malformation rate and ameliorates abnormal cardiac and neural development of zebrafish embryos exposed to arsenite. Both real-time PCR analysis and whole in-mount hybridization showed that folic acid significantly rescued the decrease in Dvr1 expression caused by arsenite. Subsequently, our data demonstrated that arsenite significantly decreased cell viability and GDF1 mRNA and protein levels in HEK293ET cells, while folic acid reversed these effects. Folic acid attenuated the increase in subcellular reactive oxygen species (ROS) levels and oxidative adaptor p66Shc protein expression in parallel with the changes in GDF1 expression and cell viability. P66Shc knockdown significantly inhibited the production of ROS and the down-regulation of GDF1 induced by arsenite. Our data demonstrated that folic acid supplementation protected against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1/GDF1, and folic acid enhanced the expression of GDF1 by decreasing p66Shc expression and subcellular ROS levels.

  11. The long noncoding RNA MALAT1 promotes tumor-driven angiogenesis by up-regulating pro-angiogenic gene expression.

    PubMed

    Tee, Andrew E; Liu, Bing; Song, Renhua; Li, Jinyan; Pasquier, Eddy; Cheung, Belamy B; Jiang, Cizhong; Marshall, Glenn M; Haber, Michelle; Norris, Murray D; Fletcher, Jamie I; Dinger, Marcel E; Liu, Tao

    2016-02-23

    Neuroblastoma is the most common solid tumor during early childhood. One of the key features of neuroblastoma is extensive tumor-driven angiogenesis due to hypoxia. However, the mechanism through which neuroblastoma cells drive angiogenesis is poorly understood. Here we show that the long noncoding RNA MALAT1 was upregulated in human neuroblastoma cell lines under hypoxic conditions. Conditioned media from neuroblastoma cells transfected with small interfering RNAs (siRNA) targeting MALAT1, compared with conditioned media from neuroblastoma cells transfected with control siRNAs, induced significantly less endothelial cell migration, invasion and vasculature formation. Microarray-based differential gene expression analysis showed that one of the genes most significantly down-regulated following MALAT1 suppression in human neuroblastoma cells under hypoxic conditions was fibroblast growth factor 2 (FGF2). RT-PCR and immunoblot analyses confirmed that MALAT1 suppression reduced FGF2 expression, and Enzyme-Linked Immunosorbent Assays revealed that transfection with MALAT1 siRNAs reduced FGF2 protein secretion from neuroblastoma cells. Importantly, addition of recombinant FGF2 protein to the cell culture media reversed the effects of MALAT1 siRNA on vasculature formation. Taken together, our data suggest that up-regulation of MALAT1 expression in human neuroblastoma cells under hypoxic conditions increases FGF2 expression and promotes vasculature formation, and therefore plays an important role in tumor-driven angiogenesis.

  12. Prolonged Starvation Causes Up-Regulation of AQP1 in Adipose Tissue Capillaries of AQP7 Knock-Out Mice

    PubMed Central

    Skowronski, Mariusz T.; Skowronska, Agnieszka; Rojek, Aleksandra; Oklinski, Michal K.; Nielsen, Søren

    2016-01-01

    Aquaporins (AQPs) are membrane proteins involved in the regulation of cellular transport and the balance of water and glycerol and cell volume in the white adipose tissue (WAT). In our previous study, we found the co-expression of the AQP1 water channel and AQP7 in the mouse WAT. In our present study, we aimed to find out whether prolonged starvation influences the AQP1 expression of AQP7 knock-out mice (AQP7 KO) in the WAT. To resolve this hypothesis, immunoperoxidase, immunoblot and immunogold microscopy were used. AQP1 expression was found with the use of immunohistochemistry and was confirmed by immunogold microscopy in the vessels of mouse WAT of all studied groups. Semi-quantitative immunoblot and quantitative immunogold microscopy showed a significant increase (by 2.5- to 3-fold) in the abundance of AQP1 protein expression in WAT in the 72 h starved AQP7 KO mice as compared to AQP7+/+ (p < 0.05) and AQP7−/− (p < 0.01) controls, respectively. In conclusion, the AQP1 water channel located in the vessels of WAT is up-regulated in response to prolonged starvation in the WAT of AQP7 KO mice. The present data suggest that an interaction of different AQP isoforms is required for maintaining proper water homeostasis within the mice WAT. PMID:27455244

  13. Up-Regulated Expression of AOS-LOXa and Increased Eicosanoid Synthesis in Response to Coral Wounding

    PubMed Central

    Lõhelaid, Helike; Teder, Tarvi; Tõldsepp, Kadri; Ekins, Merrick; Samel, Nigulas

    2014-01-01

    In octocorals, a catalase–like allene oxide synthase (AOS) and an 8R-lipoxygenase (LOX) gene are fused together encoding for a single AOS-LOX fusion protein. Although the AOS-LOX pathway is central to the arachidonate metabolism in corals, its biological function in coral homeostasis is unclear. Using an acute incision wound model in the soft coral Capnella imbricata, we here test whether LOX pathway, similar to its role in plants, can contribute to the coral damage response and regeneration. Analysis of metabolites formed from exogenous arachidonate before and after fixed time intervals following wounding indicated a significant increase in AOS-LOX activity in response to mechanical injury. Two AOS-LOX isoforms, AOS-LOXa and AOS-LOXb, were cloned and expressed in bacterial expression system as active fusion proteins. Transcription levels of corresponding genes were measured in normal and stressed coral by qPCR. After wounding, AOS-LOXa was markedly up-regulated in both, the tissue adjacent to the incision and distal parts of a coral colony (with the maximum reached at 1 h and 6 h post wounding, respectively), while AOS-LOXb was stable. According to mRNA expression analysis, combined with detection of eicosanoid product formation for the first time, the AOS-LOX was identified as an early stress response gene which is induced by mechanical injury in coral. PMID:24551239

  14. Folic acid protects against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1

    PubMed Central

    Ma, Yan; Zhang, Chen; Gao, Xiao-Bo; Luo, Hai-Yan; Chen, Yang; Li, Hui-hua; Ma, Xu; Lu, Cai-Ling

    2015-01-01

    As a nutritional factor, folic acid can prevent cardiac and neural defects during embryo development. Our previous study showed that arsenic impairs embryo development by down-regulating Dvr1/GDF1 expression in zebrafish. Here, we investigated whether folic acid could protect against arsenic-mediated embryo toxicity. We found that folic acid supplementation increases hatching and survival rates, decreases malformation rate and ameliorates abnormal cardiac and neural development of zebrafish embryos exposed to arsenite. Both real-time PCR analysis and whole in-mount hybridization showed that folic acid significantly rescued the decrease in Dvr1 expression caused by arsenite. Subsequently, our data demonstrated that arsenite significantly decreased cell viability and GDF1 mRNA and protein levels in HEK293ET cells, while folic acid reversed these effects. Folic acid attenuated the increase in subcellular reactive oxygen species (ROS) levels and oxidative adaptor p66Shc protein expression in parallel with the changes in GDF1 expression and cell viability. P66Shc knockdown significantly inhibited the production of ROS and the down-regulation of GDF1 induced by arsenite. Our data demonstrated that folic acid supplementation protected against arsenic-mediated embryo toxicity by up-regulating the expression of Dvr1/GDF1, and folic acid enhanced the expression of GDF1 by decreasing p66Shc expression and subcellular ROS levels. PMID:26537450

  15. The long noncoding RNA MALAT1 promotes tumor-driven angiogenesis by up-regulating pro-angiogenic gene expression.

    PubMed

    Tee, Andrew E; Liu, Bing; Song, Renhua; Li, Jinyan; Pasquier, Eddy; Cheung, Belamy B; Jiang, Cizhong; Marshall, Glenn M; Haber, Michelle; Norris, Murray D; Fletcher, Jamie I; Dinger, Marcel E; Liu, Tao

    2016-02-23

    Neuroblastoma is the most common solid tumor during early childhood. One of the key features of neuroblastoma is extensive tumor-driven angiogenesis due to hypoxia. However, the mechanism through which neuroblastoma cells drive angiogenesis is poorly understood. Here we show that the long noncoding RNA MALAT1 was upregulated in human neuroblastoma cell lines under hypoxic conditions. Conditioned media from neuroblastoma cells transfected with small interfering RNAs (siRNA) targeting MALAT1, compared with conditioned media from neuroblastoma cells transfected with control siRNAs, induced significantly less endothelial cell migration, invasion and vasculature formation. Microarray-based differential gene expression analysis showed that one of the genes most significantly down-regulated following MALAT1 suppression in human neuroblastoma cells under hypoxic conditions was fibroblast growth factor 2 (FGF2). RT-PCR and immunoblot analyses confirmed that MALAT1 suppression reduced FGF2 expression, and Enzyme-Linked Immunosorbent Assays revealed that transfection with MALAT1 siRNAs reduced FGF2 protein secretion from neuroblastoma cells. Importantly, addition of recombinant FGF2 protein to the cell culture media reversed the effects of MALAT1 siRNA on vasculature formation. Taken together, our data suggest that up-regulation of MALAT1 expression in human neuroblastoma cells under hypoxic conditions increases FGF2 expression and promotes vasculature formation, and therefore plays an important role in tumor-driven angiogenesis. PMID:26848616

  16. Sulfate resupply accentuates protein synthesis in coordination with nitrogen metabolism in sulfur deprived Brassica napus.

    PubMed

    Zhang, Qian; Lee, Bok-Rye; Park, Sang-Hyun; Zaman, Rashed; Avice, Jean-Christophe; Ourry, Alain; Kim, Tae-Hwan

    2015-02-01

    To investigate the regulatory interactions between S assimilation and N metabolism in Brassica napus, de novo synthesis of amino acids and proteins was quantified by (15)N and (34)S tracing, and the responses of transporter genes, assimilatory enzymes and metabolites pool involving in nitrate and sulfate metabolism were assessed under continuous sulfur supply, sulfur deprivation and sulfate resupply after 3 days of sulfur (S) deprivation. S-deprived plants were characterized by a strong induction of sulfate transporter genes, ATP sulfurylase (ATPS) and adenosine 5'-phosphosulfate reductase (APR), and by a repressed activity of nitrate reductase (NR) and glutamine synthetase (GS). Sulfate resupply to the S-deprived plants strongly increased cysteine, amino acids and proteins concentration. The increase in sulfate and cysteine concentration caused by sulfate resupply was not matched with the expression of sulfate transporters and the activity of ATPS and APR which were rapidly decreased by sulfate resupply. A strong induction of O-acetylserine(thiol)lyase (OASTL), NR and GS upon sulfate resupply was accompanied with the increase in cysteine, amino acids and proteins pool. Sulfate resupply resulted in a strong increase in de novo synthesis of amino acids and proteins, as evidenced by the increases in N and S incorporation into amino acids (1.8- and 2.4-fold increase) and proteins (2.2-and 6.3-fold increase) when compared to S-deprived plants. The results thus indicate that sulfate resupply followed by S-deprivation accelerates nitrate assimilation for protein synthesis.

  17. Database algorithm for generating protein backbone and side-chain co-ordinates from a C alpha trace application to model building and detection of co-ordinate errors.

    PubMed

    Holm, L; Sander, C

    1991-03-01

    The problem of constructing all-atom model co-ordinates of a protein from an outline of the polypeptide chain is encountered in protein structure determination by crystallography or nuclear magnetic resonance spectroscopy, in model building by homology and in protein design. Here, we present an automatic procedure for generating full protein co-ordinates (backbone and, optionally, side-chains) given the C alpha trace and amino acid sequence. To construct backbones, a protein structure database is first scanned for fragments that locally fit the chain trace according to distance criteria. A best path algorithm then sifts through these segments and selects an optimal path with minimal mismatch at fragment joints. In blind tests, using fully known protein structures, backbones (C alpha, C, N, O) can be reconstructed with a reliability of 0.4 to 0.6 A root-mean-square position deviation and not more than 0 to 5% peptide flips. This accuracy is sufficient to identify possible errors in protein co-ordinate sets. To construct full co-ordinates, side-chains are added from a library of frequently occurring rotamers using a simple and fast Monte Carlo procedure with simulated annealing. In tests on X-ray structures determined at better than 2.5 A resolution, the positions of side-chain atoms in the protein core (less than 20% relative accessibility) have an accuracy of 1.6 A (r.m.s. deviation) and 70% of chi 1 angles are within 30 degrees of the X-ray structure. The computer program MaxSprout is available on request. PMID:2002501

  18. Co-ordinated functions of Mms proteins define the surface structure of cubo-octahedral magnetite crystals in magnetotactic bacteria.

    PubMed

    Arakaki, Atsushi; Yamagishi, Ayana; Fukuyo, Ayumi; Tanaka, Masayoshi; Matsunaga, Tadashi

    2014-08-01

    Magnetotactic bacteria synthesize magnetosomes comprised of membrane-enveloped single crystalline magnetite (Fe3 O4 ). The size and morphology of the nano-sized magnetite crystals (< 100 nm) are highly regulated and bacterial species dependent. However, the control mechanisms of magnetite crystal morphology remain largely unknown. The group of proteins, called Mms (Mms5, Mms6, Mms7, and Mms13), was previously isolated from the surface of cubo-octahedral magnetite crystals in Magnetospirillum magneticum strain AMB-1. Analysis of an mms6 gene deletion mutant suggested that the Mms6 protein plays a major role in the regulation of magnetite crystal size and morphology. In this study, we constructed various mms gene deletion mutants and characterized the magnetite crystals formed by the mutant strains. Comparative analysis showed that all mms genes were involved in the promotion of crystal growth in different manners. The phenotypic characterization of magnetites also suggested that these proteins are involved in controlling the geometries of the crystal surface structures. Thus, the co-ordinated functions of Mms proteins regulate the morphology of the cubo-octahedral magnetite crystals in magnetotactic bacteria.

  19. Ciliary Neurotrophic Factor Promotes the Migration of Corneal Epithelial Stem/progenitor Cells by Up-regulation of MMPs through the Phosphorylation of Akt

    PubMed Central

    Chen, Jialin; Chen, Peng; Backman, Ludvig J.; Zhou, Qingjun; Danielson, Patrik

    2016-01-01

    The migration of limbal epithelial stem cells is important for the homeostasis and regeneration of corneal epithelium. Ciliary neurotrophic factor (CNTF) has been found to promote corneal epithelial wound healing by activating corneal epithelial stem/progenitor cells. However, the possible effect of CNTF on the migration of corneal epithelial stem/progenitor cells is not clear. This study found the expression of CNTF in mouse corneal epithelial stem/progenitor cells (TKE2) to be up-regulated after injury, on both gene and protein level. CNTF promoted migration of TKE2 in a dose-dependent manner and the peak was seen at 10 ng/ml. The phosphorylation level of Akt (p-Akt), and the expression of MMP3 and MMP14, were up-regulated after CNTF treatment both in vitro and in vivo. Akt and MMP3 inhibitor treatment delayed the migration effect by CNTF. Finally, a decreased expression of MMP3 and MMP14 was observed when Akt inhibitor was applied both in vitro and in vivo. This study provides new insights into the role of CNTF on the migration of corneal epithelial stem/progenitor cells and its inherent mechanism of Up-regulation of matrix metalloproteinases through the Akt signalling pathway. PMID:27174608

  20. Honey constituents up-regulate detoxification and immunity genes in the western honey bee Apis mellifera

    PubMed Central

    Mao, Wenfu; Schuler, Mary A.; Berenbaum, May R.

    2013-01-01

    As a managed pollinator, the honey bee Apis mellifera is critical to the American agricultural enterprise. Recent colony losses have thus raised concerns; possible explanations for bee decline include nutritional deficiencies and exposures to pesticides and pathogens. We determined that constituents found in honey, including p-coumaric acid, pinocembrin, and pinobanksin 5-methyl ether, specifically induce detoxification genes. These inducers are primarily found not in nectar but in pollen in the case of p-coumaric acid (a monomer of sporopollenin, the principal constituent of pollen cell walls) and propolis, a resinous material gathered and processed by bees to line wax cells. RNA-seq analysis (massively parallel RNA sequencing) revealed that p-coumaric acid specifically up-regulates all classes of detoxification genes as well as select antimicrobial peptide genes. This up-regulation has functional significance in that that adding p-coumaric acid to a diet of sucrose increases midgut metabolism of coumaphos, a widely used in-hive acaricide, by ∼60%. As a major component of pollen grains, p-coumaric acid is ubiquitous in the natural diet of honey bees and may function as a nutraceutical regulating immune and detoxification processes. The widespread apicultural use of honey substitutes, including high-fructose corn syrup, may thus compromise the ability of honey bees to cope with pesticides and pathogens and contribute to colony losses. PMID:23630255

  1. Water-soluble genistin glycoside isoflavones up-regulate antioxidant metallothionein expression and scavenge free radicals.

    PubMed

    Chung, Mi Ja; Kang, Ah-Young; Lee, Kyung Min; Oh, Eunji; Jun, Hee-Jin; Kim, Sang-Yeon; Auh, Joong Hyuck; Moon, Tae-Wha; Lee, Sung-Joon; Park, Kwan-Hwa

    2006-05-31

    Genistin has antioxidant activities; however, its insolubility in water often limits its biological availability in vivo. Using a novel transglycosylation process, the solubility of genistin glycosides was increased 1000 to 10000-fold, but it was not known whether these modified genistin glycosides maintained antioxidant activity. We found that both genistin and its glycosides similarly up-regulated the transcription of several metallothionein (MT) antioxidant genes (MT1A, MT2A, MT1E, and MT1X), as well as the glucose 6-phosphate dehydrogenase (G6PD) gene in HepG2 cells. This gene induction was mediated by the sequestration of zinc in the cytosol, which up-regulated the metal-responsive transcription factor-1 (MTF-1) that induced MT gene expression. Although not as effective as ascorbic acid, genistin glycosides possessed slightly greater reducing power than genistin. We concluded that genistin and genistin glycosides have a direct antioxidant effect and an indirect antioxidant effect, perhaps via induction of MT by activity of MTF-1.

  2. Low-Dose Cancer Risk Modeling Must Recognize Up-Regulation Of Protection

    PubMed Central

    Feinendegen, Ludwig E.; Pollycove, Myron; Neumann, Ronald D.

    2009-01-01

    Ionizing radiation primarily perturbs the basic molecular level proportional to dose, with potential damage propagation to higher levels: cells, tissues, organs, and whole body. There are three types of defenses against damage propagation. These operate deterministically and below a certain impact threshold there is no propagation. Physical-static defenses precede metabolic-dynamic defenses acting immediately: scavenging of toxins; - molecular repair, especially of DNA; - removal of damaged cells either by apoptosis, necrosis, phagocytosis, cell differentiation-senescence, or by immune responses, - followed by replacement of lost elements. Another metabolic-dynamic defense arises delayed by up-regulating immediately operating defense mechanisms. Some of these adaptive protections may last beyond a year and all create temporary protection against renewed potentially toxic impacts also from non-radiogenic endogenous sources. Adaptive protections have a maximum after single tissue absorbed doses around 100 to 200 mSv and disappear with higher doses. Low dose rates initiate maximum protection likely at lower cell doses delivered repetitively at certain time intervals. Adaptive protection preventing only about 2 – 3 % of endogenous life-time cancer risk would fully balance a calculated induced cancer risk at about 100 mSv, in agreement with epidemiological data and concordant with an hormetic effect. Low-dose-risk modeling must recognize up-regulation of protection. PMID:20585440

  3. N-glycoprotein analysis discovers new up-regulated glycoproteins in colorectal cancer tissue.

    PubMed

    Nicastri, Annalisa; Gaspari, Marco; Sacco, Rosario; Elia, Laura; Gabriele, Caterina; Romano, Roberto; Rizzuto, Antonia; Cuda, Giovanni

    2014-11-01

    Colorectal cancer is one of the leading causes of death due to cancer worldwide. Therefore, the identification of high-specificity and -sensitivity biomarkers for the early detection of colorectal cancer is urgently needed. Post-translational modifications, such as glycosylation, are known to play an important role in cancer progression. In the present work, we used a quantitative proteomic technique based on (18)O stable isotope labeling to identify differentially expressed N-linked glycoproteins in colorectal cancer tissue samples compared with healthy colorectal tissue from 19 patients undergoing colorectal cancer surgery. We identified 54 up-regulated glycoproteins in colorectal cancer samples, therefore potentially involved in the biological processes of tumorigenesis. In particular, nine of these (PLOD2, DPEP1, SE1L1, CD82, PAR1, PLOD3, S12A2, LAMP3, OLFM4) were found to be up-regulated in the great majority of the cohort, and, interestingly, the association with colorectal cancer of four (PLOD2, S12A2, PLOD3, CD82) has not been hitherto described.

  4. Up-regulation of vitamin B1 homeostasis genes in breast cancer.

    PubMed

    Zastre, Jason A; Hanberry, Bradley S; Sweet, Rebecca L; McGinnis, A Cary; Venuti, Kristen R; Bartlett, Michael G; Govindarajan, Rajgopal

    2013-09-01

    An increased carbon flux and exploitation of metabolic pathways for the rapid generation of biosynthetic precursors is a common phenotype observed in breast cancer. To support this metabolic phenotype, cancer cells adaptively regulate the expression of glycolytic enzymes and nutrient transporters. However, activity of several enzymes involved in glucose metabolism requires an adequate supply of cofactors. In particular, vitamin B1 (thiamine) is utilized as an essential cofactor for metabolic enzymes that intersect at critical junctions within the glycolytic network. Intracellular availability of thiamine is facilitated by the activity of thiamine transporters and thiamine pyrophosphokinase-1 (TPK-1). Therefore, the objective of this study was to establish if the cellular determinants regulating thiamine homeostasis differ between breast cancer and normal breast epithelia. Employing cDNA arrays of breast cancer and normal breast epithelial tissues, SLC19A2, SLC25A19 and TPK-1 were found to be significantly up-regulated. Similarly, up-regulation was also observed in breast cancer cell lines compared to human mammary epithelial cells. Thiamine transport assays and quantitation of intracellular thiamine and thiamine pyrophosphate established a significantly greater extent of thiamine transport and free thiamine levels in breast cancer cell lines compared to human mammary epithelial cells. Overall, these findings demonstrate an adaptive response by breast cancer cells to increase cellular availability of thiamine.

  5. Honey constituents up-regulate detoxification and immunity genes in the western honey bee Apis mellifera.

    PubMed

    Mao, Wenfu; Schuler, Mary A; Berenbaum, May R

    2013-05-28

    As a managed pollinator, the honey bee Apis mellifera is critical to the American agricultural enterprise. Recent colony losses have thus raised concerns; possible explanations for bee decline include nutritional deficiencies and exposures to pesticides and pathogens. We determined that constituents found in honey, including p-coumaric acid, pinocembrin, and pinobanksin 5-methyl ether, specifically induce detoxification genes. These inducers are primarily found not in nectar but in pollen in the case of p-coumaric acid (a monomer of sporopollenin, the principal constituent of pollen cell walls) and propolis, a resinous material gathered and processed by bees to line wax cells. RNA-seq analysis (massively parallel RNA sequencing) revealed that p-coumaric acid specifically up-regulates all classes of detoxification genes as well as select antimicrobial peptide genes. This up-regulation has functional significance in that that adding p-coumaric acid to a diet of sucrose increases midgut metabolism of coumaphos, a widely used in-hive acaricide, by ∼60%. As a major component of pollen grains, p-coumaric acid is ubiquitous in the natural diet of honey bees and may function as a nutraceutical regulating immune and detoxification processes. The widespread apicultural use of honey substitutes, including high-fructose corn syrup, may thus compromise the ability of honey bees to cope with pesticides and pathogens and contribute to colony losses.

  6. Laughter up-regulates the genes related to NK cell activity in diabetes.

    PubMed

    Hayashi, Takashi; Tsujii, Satoru; Iburi, Tadao; Tamanaha, Tamiko; Yamagami, Keiko; Ishibashi, Rieko; Hori, Miyo; Sakamoto, Shigeko; Ishii, Hitoshi; Murakami, Kazuo

    2007-12-01

    To elucidate the sustainable effects of laughter on gene expression, we recruited type 2 diabetic patients who were in-patient for receiving self-management education and examined time-dependent regulation for gene expression by laughter. Two-day experiment was performed. On one day, the patients watched comic video and laughed together with hospital staffs. On the other day, they participated in an inpatient diabetes educational program. Blood samples were collected before and 1.5, 4 h after watching comic video or spending lecture time, and changes in gene expression were comprehensively analyzed by microarray technique. Of the 41,000 genes analyzed, the laughter relatively up-regulated 39 genes, among which, 27 genes were relatively increased in the expression for all the observation period after watching comic video. By functional classification of these genes, 14 genes were found to be related to natural killer cell activity. No genes were included that are directly involved in blood glucose regulation, though successive suppression of postprandial blood glucose levels was observed. These results suggest that the laughter influences the expression of many genes classified into immune responses, and may contribute to amelioration of postprandial blood glucose elevation through a modulation of NK cell activity caused by up-regulation of relating genes.

  7. Honey constituents up-regulate detoxification and immunity genes in the western honey bee Apis mellifera.

    PubMed

    Mao, Wenfu; Schuler, Mary A; Berenbaum, May R

    2013-05-28

    As a managed pollinator, the honey bee Apis mellifera is critical to the American agricultural enterprise. Recent colony losses have thus raised concerns; possible explanations for bee decline include nutritional deficiencies and exposures to pesticides and pathogens. We determined that constituents found in honey, including p-coumaric acid, pinocembrin, and pinobanksin 5-methyl ether, specifically induce detoxification genes. These inducers are primarily found not in nectar but in pollen in the case of p-coumaric acid (a monomer of sporopollenin, the principal constituent of pollen cell walls) and propolis, a resinous material gathered and processed by bees to line wax cells. RNA-seq analysis (massively parallel RNA sequencing) revealed that p-coumaric acid specifically up-regulates all classes of detoxification genes as well as select antimicrobial peptide genes. This up-regulation has functional significance in that that adding p-coumaric acid to a diet of sucrose increases midgut metabolism of coumaphos, a widely used in-hive acaricide, by ∼60%. As a major component of pollen grains, p-coumaric acid is ubiquitous in the natural diet of honey bees and may function as a nutraceutical regulating immune and detoxification processes. The widespread apicultural use of honey substitutes, including high-fructose corn syrup, may thus compromise the ability of honey bees to cope with pesticides and pathogens and contribute to colony losses. PMID:23630255

  8. Transcriptional up-regulation of the human androgen receptor by androgen in bone cells.

    PubMed

    Wiren, K M; Zhang, X; Chang, C; Keenan, E; Orwoll, E S

    1997-06-01

    Androgen regulation of androgen receptor (AR) expression has been observed in a variety of tissues, generally as inhibition, and is thought to attenuate cellular responses to androgen. AR is expressed in osteoblasts, the bone-forming cell, suggesting direct actions of androgens on bone. Here we characterized the effect of androgen exposure on AR gene expression in human osteoblastic SaOS-2 and U-2 OS cells. Treatment of osteoblastic cells with the nonaromatizable androgen 5alpha-dihydrotestosterone increased AR steady state messenger RNA levels in a time- and dose-dependent fashion. Reporter assays with 2.3 kilobases of the proximal 5'-flanking region of the human AR promoter linked to the chloramphenicol acetyltransferase gene in transfected cultures showed that up-regulation of AR promoter activity by androgen was time and dose dependent. Treatment with other steroid hormones, including progesterone, 17beta-estradiol, and dexamethasone, was without effect. The antiandrogen hydroxyflutamide completely antagonized androgen up-regulation. Thus, in contrast to many other androgen target tissues, androgen exposure increases steady state AR messenger RNA levels in osteoblasts. This regulation occurs at least partially at the level of transcription, is mediated by the 5'-promoter region of the AR gene, and is dependent on functional AR. These results suggest that physiological concentrations of androgens have significant effects on AR expression in skeletal tissue. PMID:9165014

  9. Up-regulated Smad5 mediates apoptosis of gastric epithelial cells induced by Helicobacter pylori infection.

    PubMed

    Nagasako, Tomokazu; Sugiyama, Toshiro; Mizushima, Takuji; Miura, Yosuke; Kato, Mototsugu; Asaka, Masahiro

    2003-02-14

    The gastric pathogen Helicobacter pylori activates epithelial cell signaling pathways, and its infection induces changes in the expression of several genes in infected human gastric tissues. Recent studies have indicated that the ability of H. pylori to regulate epithelial cell responses depends on the presence of an intact cag pathogenicity island (cagPAI). We investigated altered mRNA expression of gastric epithelial cells after infection with H. pylori, both cagPAI-positive and cagPAI-negative strains, by cDNA microarray, reverse transcription PCR, and Northern blot analysis. Our results indicated that cagPAI-positive H. pylori strains (ATCC 43504 and clinical isolated strains) significantly activated Smad5 mRNA expression of human gastric epithelial cells (AGS, KATOIII, MKN28, and MKN45). We further examined whether the up-regulated Smad5 was related to apoptosis of gastric epithelial cells induced by H. pylori. Smad5 RNA interference completely inhibited H. pylori-induced apoptosis. These results suggest that Smad5 is up-regulated in gastric epithelial cells through the presence of cagPAI of H. pylori and that Smad5 mediates apoptosis of gastric epithelial cells induced by H. pylori infection. PMID:12473652

  10. Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand

    PubMed Central

    Venkatarame Gowda Saralamma, Venu; Nagappan, Arulkumar; Hong, Gyeong Eun; Lee, Ho Jeong; Yumnam, Silvia; Raha, Suchismita; Heo, Jeong Doo; Lee, Sang Joon; Lee, Won Sup; Kim, Eun Hee; Kim, Gon Sup

    2015-01-01

    Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma). The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL) protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose) polymerase (PARP). Inhibitor studies’ results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm), pro-apoptotic proteins (Bax and Bak) and anti-apoptotic protein (Bcl-xL) in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer. PMID:26393583

  11. Coordinate Regulation of G Protein Signaling via Dynamic Interactions of Receptor and GAP

    PubMed Central

    Turcotte, Marc; Tang, Wei; Ross, Elliott M.

    2008-01-01

    Signal output from receptor–G-protein–effector modules is a dynamic function of the nucleotide exchange activity of the receptor, the GTPase-accelerating activity of GTPase-activating proteins (GAPs), and their interactions. GAPs may inhibit steady-state signaling but may also accelerate deactivation upon removal of stimulus without significantly inhibiting output when the receptor is active. Further, some effectors (e.g., phospholipase C-β) are themselves GAPs, and it is unclear how such effectors can be stimulated by G proteins at the same time as they accelerate G protein deactivation. The multiple combinations of protein–protein associations and interacting regulatory effects that allow such complex behaviors in this system do not permit the usual simplifying assumptions of traditional enzyme kinetics and are uniquely subject to systems-level analysis. We developed a kinetic model for G protein signaling that permits analysis of both interactive and independent G protein binding and regulation by receptor and GAP. We evaluated parameters of the model (all forward and reverse rate constants) by global least-squares fitting to a diverse set of steady-state GTPase measurements in an m1 muscarinic receptor–Gq–phospholipase C-β1 module in which GTPase activities were varied by ∼104-fold. We provide multiple tests to validate the fitted parameter set, which is consistent with results from the few previous pre-steady-state kinetic measurements. Results indicate that (1) GAP potentiates the GDP/GTP exchange activity of the receptor, an activity never before reported; (2) exchange activity of the receptor is biased toward replacement of GDP by GTP; (3) receptor and GAP bind G protein with negative cooperativity when G protein is bound to either GTP or GDP, promoting rapid GAP binding and dissociation; (4) GAP indirectly stabilizes the continuous binding of receptor to G protein during steady-state GTPase hydrolysis, thus further enhancing receptor activity

  12. Human p38{delta} MAP kinase mediates UV irradiation induced up-regulation of the gene expression of chemokine BRAK/CXCL14

    SciTech Connect

    Ozawa, Shigeyuki; Ito, Shin; Kato, Yasumasa; Kubota, Eiro; Hata, Ryu-Ichiro

    2010-06-11

    The mitogen-activated protein kinase (MAPK) family comprises ERK, JNK, p38 and ERK5 (big-MAPK, BMK1). UV irradiation of squamous cell carcinoma cells induced up-regulation of gene expression of chemokine BRAK/CXCL14, stimulated p38 phosphorylation, and down-regulated the phosphorylation of ERK. Human p38 MAPKs exist in 4 isoforms: p38{alpha}, {beta}, {gamma} and {delta}. The UV stimulation of p38 phosphorylation was not inhibited by the presence of SB203580 or PD169316, inhibitors of p38{alpha} and {beta}, suggesting p38 phosphorylation was not dependent on these 2 isoforms and that p38{gamma} and/or {delta} was responsible for the phosphorylation. In fact, inhibition of each of these 4 p38 isoforms by the introduction of short hairpin (sh) RNAs for respective isoforms revealed that only shRNA for p38{delta} attenuated the UV-induced up-regulation of BRAK/CXCL14 gene expression. In addition, over-expression of p38 isoforms in the cells showed the association of p38{delta} with ERK1 and 2, concomitant with down-regulation of ERK phosphorylation. The usage of p38{delta} isoform by UV irradiation is not merely due to the abundance of this p38 isoform in the cells. Because serum deprivation of the cells also induced an increase in BRAK/CXCL14 gene expression, and in this case p38{alpha} and/or {beta} isoform is responsible for up-regulation of BRAK/CXCL14 gene expression. Taken together, the data indicate that the respective stress-dependent action of p38 isoforms is responsible for the up-regulation of the gene expression of the chemokine BRAK/CXCL14.

  13. Up-regulation of fibroblast growth factor (FGF) 9 expression and FGF-WNT/β-catenin signaling in laser-induced wound healing.

    PubMed

    Zheng, Zhenlong; Kang, Hye-Young; Lee, Sunha; Kang, Shin-Wook; Goo, Boncheol; Cho, Sung Bin

    2014-01-01

    Fibroblast growth factor (FGF) 9 is secreted by both mesothelial and epithelial cells, and plays important roles in organ development and wound healing via WNT/β-catenin signaling. The aim of this study was to evaluate FGF9 expression and FGF-WNT/β-catenin signaling during wound healing of the skin. We investigated FGF9 expression and FGF-WNT/β-catenin signaling after laser ablation of mouse skin and adult human skin, as well as in cultured normal human epidermal keratinocytes (NHEKs) upon stimulation with recombinant human (rh) FGF9 and rh-transforming growth factor (TGF)-β1. Our results showed that laser ablation of both mouse skin and human skin leads to marked overexpression of FGF9 and FGF9 mRNA. Control NHEKs constitutively expressed FGF9, WNT7b, WNT2, and β-catenin, but did not show Snail or FGF receptor (FGFR) 2 expression. We also found that FGFR2 was significantly induced in NHEKs by rhFGF9 stimulation, and observed that FGFR2 expression was slightly up-regulated on particular days during the wound healing process after ablative laser therapy. Both WNT7b and WNT2 showed up-regulated protein expression during the laser-induced wound healing process in mouse skin; moreover, we discerned that the stimulatory effect of rhFGF9 and rhTGF-β1 activates WNT/β-catenin signaling via WNT7b in cultured NHEKs. Our data indicated that rhFGF9 and/or rhTGF-β1 up-regulate FGFR2, WNT7b, and β-catenin, but not FGF9 and Snail; pretreatment with rh dickkopf-1 significantly inhibited the up-regulation of FGFR2, WNT7b, and β-catenin. Our results suggested that FGF9 and FGF-WNT/β-catenin signaling may play important roles in ablative laser-induced wound healing processes.

  14. Chloride ion conduction without water coordination in the pore of ClC protein.

    PubMed

    Ko, Youn Jo; Jo, Won Ho

    2010-02-01

    In the present work, we have found by an atomistic molecular dynamics simulation that hydrogen atoms originating from the residues of a prokaryotic ClC protein (EcClC) stabilize the chloride ion without water molecules in the pore of ClC protein. When the chloride ion conduction is simulated by pulling a chloride ion along the pore axis, the free energy barrier for chloride ion conduction is calculated to be low (4 kcal/mol), although the chloride ion is stripped of its hydration shell as it passes through the dehydrated pore region. The calculation of the number of hydrogen atoms surrounding the chloride ion reveals that water molecules hydrating the chloride ion are replaced by polar and non-polar hydrogen atoms protruding from the protein residues. From the analysis of the pair interaction energy between the chloride ion and these hydrogen atoms, it is realized that the hydrogen atoms from the protein residues stabilize the chloride ion at the dehydrated region instead of water molecules, by which the energetic penalty for detaching water molecules from the permeating ion is compensated.

  15. Up-regulation of CLDN1 in gastric cancer is correlated with reduced survival

    PubMed Central

    2013-01-01

    Background The genetic changes in gastric adenocarcinoma are extremely complex and reliable tumor markers have not yet been identified. There are also remarkable geographical differences in the distribution of this disease. Our aim was to identify the most differentially regulated genes in 20 gastric adenocarcinomas from a Norwegian selection, compared to matched normal mucosa, and we have related our findings to prognosis, survival and chronic Helicobacter pylori infection. Methods Biopsies from gastric adenocarcinomas and adjacent normal gastric mucosa were obtained from 20 patients immediately following surgical resection of the tumor. Whole genome, cDNA microarray analysis was performed on the RNA isolated from the sample pairs to compare the gene expression profiles between the tumor against matched mucosa. The samples were microscopically examined to classify gastritis. The presence of H. pylori was examined using microscopy and immunohistochemistry. Results 130 genes showed differential regulation above a predefined cut-off level. Interleukin-8 (IL-8) and Claudin-1 (CLDN1) were the most consistently up-regulated genes in the tumors. Very high CLDN1 expression in the tumor was identified as an independent and significant predictor gene of reduced post-operative survival. There were distinctly different expression profiles between the tumor group and the control mucosa group, and the histological subsets of mixed type, diffuse type and intestinal type cancer demonstrated further sub-clustering. Up-regulated genes were mapped to cell-adhesion, collagen-related processes and angiogenesis, whereas normal intestinal functions such as digestion and excretion were associated with down-regulated genes. We relate the current findings to our previous study on the gene response of gastric epithelial cells to H. pylori infection. Conclusions CLDN1 was highly up-regulated in gastric cancer, and CLDN1 expression was independently associated with a poor post

  16. Canonical and Noncanonical G-Protein Signaling Helps Coordinate Actin Dynamics To Promote Macrophage Phagocytosis of Zymosan

    PubMed Central

    Huang, Ning-Na; Becker, Steven; Boularan, Cedric; Kamenyeva, Olena; Vural, Ali; Hwang, Il-Young; Shi, Chong-Shan

    2014-01-01

    Both chemotaxis and phagocytosis depend upon actin-driven cell protrusions and cell membrane remodeling. While chemoattractant receptors rely upon canonical G-protein signaling to activate downstream effectors, whether such signaling pathways affect phagocytosis is contentious. Here, we report that Gαi nucleotide exchange and signaling helps macrophages coordinate the recognition, capture, and engulfment of zymosan bioparticles. We show that zymosan exposure recruits F-actin, Gαi proteins, and Elmo1 to phagocytic cups and early phagosomes. Zymosan triggered an increase in intracellular Ca2+ that was partially sensitive to Gαi nucleotide exchange inhibition and expression of GTP-bound Gαi recruited Elmo1 to the plasma membrane. Reducing GDP-Gαi nucleotide exchange, decreasing Gαi expression, pharmacologically interrupting Gβγ signaling, or reducing Elmo1 expression all impaired phagocytosis, while favoring the duration that Gαi remained GTP bound promoted it. Our studies demonstrate that targeting heterotrimeric G-protein signaling offers opportunities to enhance or retard macrophage engulfment of phagocytic targets such as zymosan. PMID:25225330

  17. A new arene-Ru based supramolecular coordination complex for efficient binding and selective sensing of green fluorescent protein.

    PubMed

    Mishra, Anurag; Ravikumar, Sambandam; Song, Young Ho; Prabhu, Nadarajan Saravanan; Kim, Hyunuk; Hong, Soon Ho; Cheon, Seyeon; Noh, Jaegeun; Chi, Ki-Whan

    2014-04-28

    A new dipyridyl ligand is encoded with 120° angularity between its coordination vectors by using a central pyridine carboxamide scaffold to orient two 4-(pyridin-4-ylethynyl)phenyl moieties. The N,N'-bis(4-(pyridin-4-ylethynyl)phenyl)pyridine-2,6-dicarboxamide ligand undergoes self-assembly with a diruthenium arene complex to furnish a [2 + 2] metallacycle with a wedge-like structure. The metallacycle binds to the enhanced green fluorescent protein (EGFP) variant of GFP, resulting in steady-state spectral changes in UV-Vis absorption and emission experiments. These studies indicate that the metallacycle induces conformation changes to the EGFP, disrupting the tripeptide chromophore. Furthermore, gel electrophoresis, circular dichroism and atomic force microscopy studies indicate that binding ultimately leads to aggregation of the protein. Computational investigations indicate a favorable interaction, predominantly between the metallacycle and the Arg168 residue of the EGFP. An interaction with Arg168 and related residues was previously observed for an emission-attenuating antibody, supporting that these interactions induce changes to the photophysical properties of EGFP by disrupting the tripeptidechromophore in a similar manner. Additionally, we have also described the quenching study of the reporter GFP protein in vivo by a new metal complex using reflected fluorescence microscopy. We anticipate that such metal complexes which can passively diffuse into the cells in vivo can serve as potential tools in molecular and drug targeting based biological studies.

  18. Developmentally regulated GTP-binding protein 2 coordinates Rab5 activity and transferrin recycling

    PubMed Central

    Mani, Muralidharan; Lee, Unn Hwa; Yoon, Nal Ae; Kim, Hyo Jeong; Ko, Myoung Seok; Seol, Wongi; Joe, Yeonsoo; Chung, Hun Taeg; Lee, Byung Ju; Moon, Chang Hoon; Cho, Wha Ja; Park, Jeong Woo

    2016-01-01

    The small GTPase Rab5 regulates the early endocytic pathway of transferrin (Tfn), and Rab5 deactivation is required for Tfn recycling. Rab5 deactivation is achieved by RabGAP5, a GTPase-activating protein, on the endosomes. Here we report that recruitment of RabGAP5 is insufficient to deactivate Rab5 and that developmentally regulated GTP-binding protein 2 (DRG2) is required for Rab5 deactivation and Tfn recycling. DRG2 was associated with phosphatidylinositol 3-phosphate–containing endosomes. It colocalized and interacted with EEA1 and Rab5 on endosomes in a phosphatidylinositol 3-kinase–dependent manner. DRG2 depletion did not affect Tfn uptake and recruitment of RabGAP5 and Rac1 to Rab5 endosomes. However, it resulted in impairment of interaction between Rab5 and RabGAP5, Rab5 deactivation on endosomes, and Tfn recycling. Ectopic expression of shRNA-resistant DRG2 rescued Tfn recycling in DRG2-depleted cells. Our results demonstrate that DRG2 is an endosomal protein and a key regulator of Rab5 deactivation and Tfn recycling. PMID:26582392

  19. Up-regulation of inducible nitric oxide synthase expression in cancer-prone p53 knockout mice.

    PubMed

    Ambs, S; Ogunfusika, M O; Merriam, W G; Bennett, W P; Billiar, T R; Harris, C C

    1998-07-21

    High concentrations of nitric oxide (NO) cause DNA damage and apoptosis in many cell types. Thus, regulation of NO synthase (NOS) activity is essential for minimizing effects of cytotoxic and genotoxic nitrogen oxide species. We have shown previously that NO-induced p53 protein accumulation down-regulates basal and cytokine-modulated inducible NOS (NOS2) expression in human cells in vitro. To further characterize the feedback loop between NOS2 and p53, we have investigated NO production, i.e., urinary nitrate plus nitrite excretion, and NOS2 expression in homozygous p53 knockout (KO) mice. We report here that untreated p53 KO mice excreted 70% more nitrite plus nitrate than mice with wild-type (wt) p53. NOS2 protein expression was constitutively detected in the spleen of untreated p53 KO mice, whereas it was undetectable in the spleen of wt p53 controls. Upon treatment with heat-inactivated Corynebacterium parvum, urinary nitrite plus nitrate excretion of p53 KO mice exceeded that of wt controls by approximately 200%. C. parvum treatment also induced p53 accumulation in the liver. Splenectomy reduced the NO output of C. parvum-treated p53 KO mice but not of wt p53 controls. Although NO production and NOS2 protein expression were increased similarly in KO and wt p53 mice 10 days after injection of C. parvum, NOS2 expression returned to baseline levels only in wt p53 controls while remaining up-regulated in p53 KO mice. These genetic and functional data indicate that p53 is an important transrepressor of NOS2 expression in vivo and attenuates excessive NO production in a regulatory negative feedback loop. PMID:9671763

  20. Gene transcription of TLR2, TLR4, LPS ligands and prostaglandin synthesis enzymes are up-regulated in canine uteri with cystic endometrial hyperplasia-pyometra complex.

    PubMed

    Silva, E; Leitão, S; Henriques, S; Kowalewski, M P; Hoffmann, B; Ferreira-Dias, G; da Costa, L Lopes; Mateus, L

    2010-01-01

    Escherichia coli (E. coli) is the most frequent bacterium isolated in cases of cystic endometrial hyperplasia-pyometra complex, the most frequent endometrial disorder in the bitch. Toll-like receptors (TLRs) play an essential role in the innate immune system. The aim of this study was to compare transcription of genes encoding TLR2, TLR4 and LPS ligands (CD14, MD-2, LBP), prostaglandin synthesis enzymes (COX1, COX2, PGES1 and PGFS), and to compare COX1 and COX2 protein expression and PGE(2) and PGF(2alpha) endometrial content in the endometrium of canine diestrous uteri with (n=7) or without (n=7) pyometra. All cases of pyometra were hyperplastic and E. coli was the only isolated bacteria, while diestrous normal uteri did not present signs of cystic endometrial hyperplasia and were negative for bacteriology. Except for COX1, transcription of all genes was significantly higher in pyometra than in normal endometria. COX1 protein was observed in both normal and pyometra uteri, but COX2 protein was only present in pyometra cases. Endometrial PGE(2) and PGF(2alpha) content were significantly higher in pyometra than in normal diestrous endometria. In conclusion, data obtained in this study provides evidence that pyometra-isolated E. coli induces the up-regulation of TLR2 and TLR4 genes in the canine diestrous endometrium. This up-regulation, which is probably the result of the stimulation by LPS and lipoprotein E. coli constituents, leads to the endometrial up-regulation of PG synthesis genes. This, in turn, results in a higher endometrial concentration of PGE(2) and PGF(2alpha), which may further regulate the local inflammatory response. PMID:19945173

  1. Physiological effects of major up-regulated Alnus glutinosa peptides on Frankia sp. ACN14a.

    PubMed

    Carro, Lorena; Pujic, Petar; Alloisio, Nicole; Fournier, Pascale; Boubakri, Hasna; Poly, Franck; Rey, Marjolaine; Heddi, Abdelaziz; Normand, Philippe

    2016-07-01

    Alnus glutinosa has been shown previously to synthesize, in response to nodulation by Frankia sp. ACN14a, an array of peptides called Alnus symbiotic up-regulated peptides (ASUPs). In a previous study one peptide (Ag5) was shown to bind to Frankia nitrogen-fixing vesicles and to modify their porosity. Here we analyse four other ASUPs, alongside Ag5, to determine whether they have different physiological effects on in vitro grown Frankia sp. ACN14a. The five studied peptides were shown to have different effects on nitrogen fixation, respiration, growth, the release of ions and amino acids, as well as on cell clumping and cell lysis. The mRNA abundance for all five peptides was quantified in symbiotic nodules and one (Ag11) was found to be more abundant in the meristem part of the nodule. These findings point to some peptides having complementary effects on Frankia cells. PMID:27082768

  2. Fetal nicotine exposure produces postnatal up-regulation of adenylate cyclase activity in peripheral tissues

    SciTech Connect

    Slotkin, T.A.; Navarro, H.A.; McCook, E.C.; Seidler, F.J. )

    1990-01-01

    Gestational exposure to nicotine has been shown to affect development of noradrenergic activity in both the central and peripheral nervous systems. In the current study, pregnant rats received nicotine infusions of 6 mg/kg/day throughout gestation, administered by osmotic minipump implants. After birth, offspring of the nicotine-infused dams exhibited marked increases in basal adenylate cyclase activity in membranes prepared from kidney and heart, as well as supersensitivity to stimulation by either a {beta}-adrenergic agonist, isoproterenol, or by forskolin. The altered responses were not accompanied by up-regulation of {beta}-adrenergic receptors: in fact, ({sup 125}I)pindolol binding was significantly decreased in the nicotine group. These results indicate that fetal nicotine exposure affects enzymes involved in membrane receptor signal transduction, leading to altered responsiveness independently of changes at the receptor level.

  3. Water deprivation up-regulates urine osmolality and renal aquaporin 2 in Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Xu, Meng-Meng; Wang, De-Hua

    2016-04-01

    To better understand how desert rodents adapt to water scarcity, we examined urine osmolality, renal distribution and expression of aquaporins (AQPs) in Mongolian gerbils (Meriones unguiculatus) during 7 days of water deprivation (WD). Urine osmolality of the gerbils during WD averaged 7503 mOsm kg(-1). Renal distributions of AQP1, AQP2, and AQP3 were similar to that described in other rodents. After the 7 day WD, renal AQP2 was up-regulated, while resting metabolic rate and total evaporative water loss decreased by 43% and 36%, respectively. Our data demonstrated that Mongolian gerbils showed high urine concentration, renal AQPs expression and body water conservation to cope with limited water availability, which may be critical for their survival during dry seasons in cold deserts. PMID:26806059

  4. Maggot debridement therapy promotes diabetic foot wound healing by up-regulating endothelial cell activity.

    PubMed

    Sun, Xinjuan; Chen, Jin'an; Zhang, Jie; Wang, Wei; Sun, Jinshan; Wang, Aiping

    2016-03-01

    To determine the role of maggot debridement therapy (MDT) on diabetic foot wound healing, we compared growth related factors in wounds before and after treatment. Furthermore, we utilized human umbilical vein endothelial cells (HUVECs) to explore responses to maggot excretions/secretions on markers of angiogenesis and proliferation. The results showed that there was neo-granulation and angiogenesis in diabetic foot wounds after MDT. Moreover, significant elevation in CD34 and CD68 levels was also observed in treated wounds. In vitro, ES increased HUVEC proliferation, improved tube formation, and increased expression of vascular endothelial growth factor receptor 2 in a dose dependent manner. These results demonstrate that MDT and maggot ES can promote diabetic foot wound healing by up-regulating endothelial cell activity.

  5. Exercise-induced up-regulation of MMP-1 and IL-8 genes in endurance horses

    PubMed Central

    Cappelli, Katia; Felicetti, Michela; Capomaccio, Stefano; Pieramati, Camillo; Silvestrelli, Maurizio; Verini-Supplizi, Andrea

    2009-01-01

    Background The stress response is a critical factor in the training of equine athletes; it is important for performance and for protection of the animal against physio-pathological disorders. In this study, the molecular mechanisms involved in the response to acute and strenuous exercise were investigated using peripheral blood mononuclear cells (PBMCs). Results Quantitative real-time PCR (qRT-PCR) was used to detect modifications in transcription levels of the genes for matrix metalloproteinase-1 (MMP-1) and interleukin 8 (IL-8), which were derived from previous genome-wide expression analysis. Significant up-regulation of these two genes was found in 10 horses that had completed a race of 90–120 km in a time-course experimental design. Conclusion These results suggest that MMP-1 and IL-8 are both involved in the exercise-induced stress response, and this represents a starting point from which to understand the adaptive responses to this phenomenon. PMID:19552796

  6. Chromatin remodelling and antisense-mediated up-regulation of the developmental switch gene eud-1 control predatory feeding plasticity

    PubMed Central

    Serobyan, Vahan; Xiao, Hua; Namdeo, Suryesh; Rödelsperger, Christian; Sieriebriennikov, Bogdan; Witte, Hanh; Röseler, Waltraud; Sommer, Ralf J.

    2016-01-01

    Phenotypic plasticity has been suggested to act through developmental switches, but little is known about associated molecular mechanisms. In the nematode Pristionchus pacificus, the sulfatase eud-1 was identified as part of a developmental switch controlling mouth-form plasticity governing a predatory versus bacteriovorous mouth-form decision. Here we show that mutations in the conserved histone-acetyltransferase Ppa-lsy-12 and the methyl-binding-protein Ppa-mbd-2 mimic the eud-1 phenotype, resulting in the absence of one mouth-form. Mutations in both genes cause histone modification defects and reduced eud-1 expression. Surprisingly, Ppa-lsy-12 mutants also result in the down-regulation of an antisense-eud-1 RNA. eud-1 and antisense-eud-1 are co-expressed and further experiments suggest that antisense-eud-1 acts through eud-1 itself. Indeed, overexpression of the antisense-eud-1 RNA increases the eud-1-sensitive mouth-form and extends eud-1 expression. In contrast, this effect is absent in eud-1 mutants indicating that antisense-eud-1 positively regulates eud-1. Thus, chromatin remodelling and antisense-mediated up-regulation of eud-1 control feeding plasticity in Pristionchus. PMID:27487725

  7. Apocynin improving cardiac remodeling in chronic renal failure disease is associated with up-regulation of epoxyeicosatrienoic acids.

    PubMed

    Zhang, Kun; Liu, Yu; Liu, Xiaoqiang; Chen, Jie; Cai, Qingqing; Wang, Jingfeng; Huang, Hui

    2015-09-22

    Cardiac remodeling is one of the most common cardiac abnormalities and associated with a high mortality in chronic renal failure (CRF) patients. Apocynin, a nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase inhibitor, has been showed cardio-protective effects. However, whether apocynin can improve cardiac remodeling in CRF and what is the underlying mechanism are unclear. In the present study, we enrolled 94 participants. In addition, we used 5/6 nephrectomized rats to mimic cardiac remodeling in CRF. Serum levels of epoxyeicosatrienoic acids (EETs) and its mainly metabolic enzyme-soluble epoxide hydrolase (sEH) were measured. The results showed that the serum levels of EETs were significantly decreased in renocardiac syndrome participants (P < 0.05). In 5/6 nephrectomized CRF model, the ratio of left ventricular weight / body weight, left ventricular posterior wall thickness, and cardiac interstitial fibrosis were significantly increased while ejection fraction significantly decreased (P < 0.05). All these effects could partly be reversed by apocynin. Meanwhile, we found during the process of cardiac remodeling in CRF, apocynin significantly increased the reduced serum levels of EETs and decreased the mRNA and protein expressions of sEH in the heart (P < 0.05). Our findings indicated that the protective effect of apocynin on cardiac remodeling in CRF was associated with the up-regulation of EETs. EETs may be a new mediator for the injury of kidney-heart interactions.

  8. MIP-1α enhances Jurkat cell transendothelial migration by up-regulating endothelial adhesion molecules VCAM-1 and ICAM-1.

    PubMed

    Ma, Yi-Ran; Ma, Ying-Huan

    2014-11-01

    The aim of this study is to evaluate the expression of macrophage inflammatory protein-1α (MIP-1α) in Jurkat cells and its effect on transendothelial migration. In the present study, human acute lymphoblastic leukemia Jurkat cells (Jurkat cells) were used as a model of T cells in human T-cell acute lymphoblastic leukemia (T-ALL), which demonstrated significantly higher MIP-1α expression compared with that in normal T-cell controls. The ability of Jurkat cells to cross a human brain microvascular endothelial cell (HBMEC) monolayer was almost completely abrogated by MIP-1α siRNA. In addition, the overexpression of MIP-1α resulted in the up-regulated expression of endothelial adhesion molecules, which enhanced the migration of Jurkat cells through a monolayer of HBMEC. MIP-1α levels in Jurkat cells appeared to be an important factor for its transendothelial migration, which may provide the theoretical basis to understand the mechanisms of brain metastases of T-ALL at cellular and molecular levels.

  9. Hepatic and Nephric NRF2 Pathway Up-Regulation, an Early Antioxidant Response, in Acute Arsenic-Exposed Mice

    PubMed Central

    Li, Jinlong; Duan, Xiaoxu; Dong, Dandan; Zhang, Yang; Li, Wei; Zhao, Lu; Nie, Huifang; Sun, Guifan; Li, Bing

    2015-01-01

    Inorganic arsenic (iAs), a proven human carcinogen, damages biological systems through multiple mechanisms, one of them being reactive oxygen species (ROS) production. NRF2 is a redox-sensitive transcription factor that positively regulates the genes of encoding antioxidant and detoxification enzymes to neutralize ROS. Although NRF2 pathway activation by iAs has been reported in various cell types, however, the experimental data in vivo are very limited and not fully elucidated in humans. The present investigation aimed to explore the hepatic and nephric NRF2 pathway upregulation in acute arsenic-exposed mice in vivo. Our results showed 10 mg/kg NaAsO2 elevated the NRF2 protein and increased the transcription of Nrf2 mRNA, as well as up-regulated NRF2 downstream targets HO-1, GST and GCLC time- and dose-dependently both in the liver and kidney. Acute NaAsO2 exposure also resulted in obvious imbalance of oxidative redox status represented by the increase of GSH and MDA, and the decrease of T-AOC. The present investigation reveals that hepatic and nephric NRF2 pathway expression is an early antioxidant defensive response upon iAs exposure. A better knowledge about the NRF2 pathway involvment in the cellular response against arsenic could help improve the strategies for reducing the cellular toxicity related to this metalloid. PMID:26473898

  10. Up-regulation of BRAF activated non-coding RNA is associated with radiation therapy for lung cancer.

    PubMed

    Chen, Jian-xiang; Chen, Ming; Zheng, Yuan-da; Wang, Sheng-ye; Shen, Zhu-ping

    2015-04-01

    Radiation therapy has become more effective in treating primary tumors, such as lung cancer. Recent evidence suggested that BRAF activated non-coding RNAs (BANCR) play a critical role in cellular processes and are found to be dysregulated in a variety of cancers. The clinical significance of BANCR in radiation therapy, and its molecular mechanisms controlling tumor growth are unclear. In the present study, C57BL/6 mice were inoculated Lewis lung cancer cells and exposed to radiation therapy, then BANCR expression was analyzed using qPCR. Chromatin immunoprecipitation and western blot were performed to calculate the enrichment of histone acetylation and HDAC3 protein levels in Lewis lung cancer cells, respectively. MTT assay was used to evaluate the effects of BANCR on Lewis lung cancer cell viability. Finally, we found that BANCR expression was significantly increased in C57BL/6 mice receiving radiation therapy (P<0.05) compared with control group. Additionally, knockdown of BANCR expression was associated with larger tumor size in C57BL/6 mice inoculated Lewis lung cancer cells. Histone deacetylation was observed to involve in the regulation of BANCR in Lewis lung cancer cells. Moreover, over expression HDAC3 reversed the effect of rays on BANCR expression. MTT assay showed that knockdown of BANCR expression promoted cell viability surviving from radiation. In conclusion, these findings indicated that radiation therapy was an effective treatment for lung cancer, and it may exert function through up-regulation BANCR expression.

  11. Azelastine hydrochloride (Azeptin) inhibits peplomycin (PLM)-induced pulmonary fibrosis by contradicting the up-regulation of signal transduction.

    PubMed

    Yoneda, K; Yamamoto, T; Ueta, E; Osaki, T

    1997-10-01

    Inhibition of peplomycin (PLM)-induced pulmonary fibrosis by azelastine hydrochloride (Azeptin) was examined using ICR mice, and the effects of both drugs on signal transduction were investigated. Microscopically, Azeptin (a total of 56 mg/kg for 28 days) suppressed pulmonary fibrosis in mice which received an i.p. injection of a total of 60 or 75 mg/kg PLM. In parallel with the microscopic findings, smaller amounts of collagen were synthesized in the lungs of Azeptin-injected mice. PLM enhanced the expression of interleukin-1 beta- and transforming growth factor-beta-mRNA in lungs. In contrast, Azeptin suppressed the expression. Compatible with these in vivo results, Azeptin and PLM contradictively regulated protein tyrosine phosphorylation and c-myc mRNA expression in human gingival and mouse pulmonary fibroblasts. In addition, NF-kappa B was activated by fibroblast treatment with 5 micrograms/ml PLM for 1 h, but intranuclear NF-kappa B was decreased by cell treatment with 10(-5) M Azeptin. From these results, it is concluded that Azeptin inhibits PLM-induced pulmonary fibrosis by antagonizing the up-regulation of signal transduction.

  12. Induction of release and up-regulated gene expression of interleukin (IL)-8 in A549 cells by serine proteinases

    PubMed Central

    Wang, Haiyan; Zheng, Yanshan; He, Shaoheng

    2006-01-01

    Background Hypersecretion of cytokines and serine proteinases has been observed in asthma. Since protease-activated receptors (PARs) are receptors of several serine proteinases and airway epithelial cells are a major source of cytokines, the influence of serine proteinases and PARs on interleukin (IL)-8 secretion and gene expression in cultured A549 cells was examined. Results A549 cells express all four PARs at both protein and mRNA levels as assessed by flow cytometry, immunofluorescence microscopy and reverse transcription polymerase chain reaction (PCR). Thrombin, tryptase, elastase and trypsin induce a up to 8, 4.3, 4.4 and 5.1 fold increase in IL-8 release from A549 cells, respectively following 16 h incubation period. The thrombin, elastase and trypsin induced secretion of IL-8 can be abolished by their specific inhibitors. Agonist peptides of PAR-1, PAR-2 and PAR-4 stimulate up to 15.6, 6.6 and 3.5 fold increase in IL-8 secretion, respectively. Real time PCR shows that IL-8 mRNA is up-regulated by the serine proteinases tested and by agonist peptides of PAR-1 and PAR-2. Conclusion The proteinases, possibly through activation of PARs can stimulate IL-8 release from A549 cells, suggesting that they are likely to contribute to IL-8 related airway inflammatory disorders in man. PMID:16696869

  13. Coordinate synthesis and protein localization in a bacterial organelle by the action of a penicillin-binding-protein

    PubMed Central

    Hughes, H. Velocity; Lisher, John P.; Hardy, Gail G.; Kysela, David T.; Arnold, Randy J.; Giedroc, David P.; Brun, Yves V.

    2013-01-01

    SUMMARY Organelles with specialized form and function occur in diverse bacteria. Within the Alphaproteobacteria, several species extrude thin cellular appendages known as stalks, which function in nutrient uptake, buoyancy and reproduction. Consistent with their specialization, stalks maintain a unique molecular composition compared to the cell body, but how this is achieved remains to be fully elucidated. Here we dissect the mechanism of localization of StpX, a stalk-specific protein in Caulobacter crescentus. Using a forward genetics approach, we identify a penicillin-bindingprotein PbpC, which is required for the localization of StpX in the stalk. We show that PbpC acts at the stalked cell pole to anchor StpX to rigid components of the outer membrane of the elongating stalk, concurrent with stalk synthesis. Stalklocalized StpX in turn functions in cellular responses to copper and zinc, suggesting that the stalk may contribute to metal homeostasis in Caulobacter. Together, these results identify a novel role for a penicillin-binding-protein in compartmentalizing a bacterial organelle it itself helps create, raising the possibility that cell wallsynthetic enzymes may broadly serve not only to synthesize the diverse shapes of bacteria, but also to functionalize them at the molecular level. PMID:24118129

  14. Mitotic Protein CSPP1 Interacts with CENP-H Protein to Coordinate Accurate Chromosome Oscillation in Mitosis.

    PubMed

    Zhu, Lijuan; Wang, Zhikai; Wang, Wenwen; Wang, Chunli; Hua, Shasha; Su, Zeqi; Brako, Larry; Garcia-Barrio, Minerva; Ye, Mingliang; Wei, Xuan; Zou, Hanfa; Ding, Xia; Liu, Lifang; Liu, Xing; Yao, Xuebiao

    2015-11-01

    Mitotic chromosome segregation is orchestrated by the dynamic interaction of spindle microtubules with the kinetochores. During chromosome alignment, kinetochore-bound microtubules undergo dynamic cycles between growth and shrinkage, leading to an oscillatory movement of chromosomes along the spindle axis. Although kinetochore protein CENP-H serves as a molecular control of kinetochore-microtubule dynamics, the mechanistic link between CENP-H and kinetochore microtubules (kMT) has remained less characterized. Here, we show that CSPP1 is a kinetochore protein essential for accurate chromosome movements in mitosis. CSPP1 binds to CENP-H in vitro and in vivo. Suppression of CSPP1 perturbs proper mitotic progression and compromises the satisfaction of spindle assembly checkpoint. In addition, chromosome oscillation is greatly attenuated in CSPP1-depleted cells, similar to what was observed in the CENP-H-depleted cells. Importantly, CSPP1 depletion enhances velocity of kinetochore movement, and overexpression of CSPP1 decreases the speed, suggesting that CSPP1 promotes kMT stability during cell division. Specific perturbation of CENP-H/CSPP1 interaction using a membrane-permeable competing peptide resulted in a transient mitotic arrest and chromosome segregation defect. Based on these findings, we propose that CSPP1 cooperates with CENP-H on kinetochores to serve as a novel regulator of kMT dynamics for accurate chromosome segregation.

  15. Axl receptor tyrosine kinase is up-regulated in metformin resistant prostate cancer cells

    PubMed Central

    Bansal, Nitu; Mishra, Prasun J.; Stein, Mark; DiPaola, Robert S.; Bertino, Joseph R.

    2015-01-01

    Recent epidemiological studies showed that metformin, a widely used anti-diabetic drug might prevent certain cancers. Metformin also has an anti-proliferative effect in preclinical studies of both hematologic malignancies as well as solid cancers and clinical studies testing metformin as an anti-cancer drug are in progress. However, all cancer types do not respond to metformin with the same effectiveness or acquire resistance. To understand the mechanism of acquired resistance and possibly its mechanism of action as an anti-proliferative agent, we developed metformin resistant LNCaP prostate cancer cells. Metformin resistant LNCaP cells had an increased proliferation rate, increased migration and invasion ability as compared to the parental cells, and expressed markers of epithelial-mesenchymal transition (EMT). A detailed gene expression microarray comparing the resistant cells to the wild type cells revealed that Edil2, Ereg, Axl, Anax2, CD44 and Anax3 were the top up-regulated genes and calbindin 2 and TPTE (transmembrane phosphatase with tensin homology) and IGF1R were down regulated. We focused on Axl, a receptor tyrosine kinase that has been shown to be up regulated in several drug resistance cancers. Here, we show that the metformin resistant cell line as well as castrate resistant cell lines that over express Axl were more resistant to metformin, as well as to taxotere compared to androgen sensitive LNCaP and CWR22 cells that do not overexpress Axl. Forced overexpression of Axl in LNCaP cells decreased metformin and taxotere sensitivity and knockdown of Axl in resistant cells increased sensitivity to these drugs. Inhibition of Axl activity by R428, a small molecule Axl kinase inhibitor, sensitized metformin resistant cells that overexpressed Axl to metformin. Inhibitors of Axl may enhance tumor responses to metformin and other chemotherapy in cancers that over express Axl. PMID:26036314

  16. Up-regulation of GLT-1 severely impairs LTD at mossy fibre--CA3 synapses.

    PubMed

    Omrani, Azar; Melone, Marcello; Bellesi, Michele; Safiulina, Victoria; Aida, Tomomi; Tanaka, Kohishi; Cherubini, Enrico; Conti, Fiorenzo

    2009-10-01

    Glutamate transporters are responsible for clearing synaptically released glutamate from the extracellular space. By this action, they maintain low levels of ambient glutamate, thus preventing excitotoxic damage, and contribute to shaping synaptic currents. We show that up-regulation of the glutamate transporter GLT-1 by ceftriaxone severely impaired mGluR-dependent long-term depression (LTD), induced at rat mossy fibre (MF)-CA3 synapses by repetitive stimulation of afferent fibres. This effect involved GLT-1, since LTD was rescued by the selective GLT-1 antagonist dihydrokainate (DHK). DHK per se produced a modest decrease in fEPSP amplitude that rapidly regained control levels after DHK wash out. Moreover, the degree of fEPSP inhibition induced by the low-affinity glutamate receptor antagonist gamma-DGG was similar during basal synaptic transmission but not during LTD, indicating that in ceftriaxone-treated rats LTD induction did not alter synaptic glutamate transient concentration. Furthermore, ceftriaxone-induced GLT-1 up-regulation significantly reduced the magnitude of LTP at MF-CA3 synapses but not at Schaffer collateral-CA1 synapses. Postembedding immunogold studies in rats showed an increased density of gold particles coding for GLT-1a in astrocytic processes and in mossy fibre terminals; in the latter, gold particles were located near and within the active zones. In both CEF-treated and untreated GLT-1 KO mice used for verifying the specificity of immunostaining, the density of gold particles in MF terminals was comparable to background levels. The enhanced expression of GLT-1 at release sites may prevent activation of presynaptic receptors, thus revealing a novel mechanism by which GLT-1 regulates synaptic plasticity in the hippocampus.

  17. Expression of murine Unc93b1 is up-regulated by interferon and estrogen signaling: implications for sex bias in the development of autoimmunity.

    PubMed

    Panchanathan, Ravichandran; Liu, Hongzhu; Choubey, Divaker

    2013-09-01

    The endoplasmic reticulum transmembrane protein, Unc93b1, is essential for trafficking of endosomal TLRs from the endoplasmic reticulum to endosomes. A genetic defect in the human UNC93B1 gene is associated with immunodeficiency. However, systemic lupus erythematosus (SLE) patients express increased levels of the UNC93B1 protein in B cells. Because SLE in patients and certain mouse models exhibits a sex bias and increased serum levels of type I interferons in patients are associated with the disease activity, we investigated whether the female sex hormone estrogen (E2) or type I interferon signaling could up-regulate the expression of the murine Unc93b1 gene. We found that steady-state levels of Unc93b1 mRNA and protein were measurably higher in immune cells (CD3(+), B220(+), CD11b(+) and CD11c(+)) isolated from C57BL/6 (B6) females than age-matched males. Moreover, treatment of CD11b(+) and B220(+) cells with E2 or interferons (IFN-α, IFN-β or IFN-γ) significantly increased the levels of Unc93b1 mRNA and protein. Accordingly, a deficiency of estrogen receptor-α or STAT1 expression in immune cells decreased the expression levels of the Unc93b1 protein. Interestingly, levels of Unc93b1 protein were appreciably higher in B6.Nba2 lupus-prone female mice compared with age-matched B6 females. Furthermore, increased expression of the interferon- and E2-inducible p202 protein in a murine macrophage cell line (RAW264.7) increased the levels of the Unc93b1 protein, whereas knockdown of p202 expression reduced the levels. To our knowledge, our observations demonstrate for the first time that activation of interferon and estrogen signaling in immune cells up-regulates the expression of murine Unc93b1. PMID:23728775

  18. Coordinated regulation of mesenchymal stem cell differentiation on microstructured titanium surfaces by endogenous bone morphogenetic proteins.

    PubMed

    Olivares-Navarrete, Rene; Hyzy, Sharon L; Haithcock, David A; Cundiff, Caitlin A; Schwartz, Zvi; Boyan, Barbara D

    2015-04-01

    Human mesenchymal stem cells (MSCs) differentiate into osteoblasts on microstructured titanium (Ti) surfaces without addition of medium supplements, suggesting that surface-dependent endogenous mechanisms are involved. They produce bone morphogenetic proteins (BMPs), which regulate MSC differentiation and bone formation via autocrine/paracrine mechanisms that are modulated by changes in BMP mRNA and protein, receptors, and inhibitors (Noggin, Cerberus, Gremlin 1, and Chordin). We examined expression of BMPs, their receptors and their inhibitors over time and used BMP2-silenced cells to determine how modulating endogenous BMP signaling can affect the process. MSCs were cultured on tissue culture polystyrene or Ti [PT (Ra<0.4 μm); sandblasted/acid-etched Ti (SLA, Ra=3.2 μm); or hydrophilic-SLA (modSLA)]. BMP mRNAs and proteins increased by day 4 of culture. Exogenous BMP2 increased differentiation whereas differentiation was decreased in BMP2-silenced cells. Noggin was regulated by day 2 whereas Gremlin 1 and Cerberus were regulated after 6days. Osteoblastic differentiation increased in cells cultured with blocking antibodies against Noggin, Gremlin 1, and Cerberus. Endogenous BMPs enhance an osteogenic microenvironment whereas exogenous BMPs are inhibitory. Antibody blocking of the BMP2 inhibitor Cerberus resulted in IL-6 and IL-8 levels that were similar to those observed when treating cells with exogenous BMP2, while antibodies targeting the inhibitors Gremlin or Noggin did not. These results suggest that microstructured titanium implants supporting therapeutic stem cells may be treated with appropriately selected agents antagonistic to extracellular BMP inhibitors in order to enhance BMP2 mediated bone repair while avoiding undesirable inflammatory side effects observed with exogenous BMP2 treatment. PMID:25554602

  19. Novel durum wheat genes up-regulated in response to a combination of heat and drought stress.

    PubMed

    Rampino, Patrizia; Mita, Giovanni; Fasano, Pasqua; Borrelli, Grazia Maria; Aprile, Alessio; Dalessandro, Giuseppe; De Bellis, Luigi; Perrotta, Carla

    2012-07-01

    We report the effect of heat, drought and combined stress on the expression of a group of genes that are up-regulated under these conditions in durum wheat (Triticum turgidum subsp. durum) plants. Modulation of gene expression was studied by cDNA-AFLP performed on RNAs extracted from flag leaves. By this approach, we identified several novel durum wheat genes whose expression is modulated under different stress conditions. We focused on a group of hitherto undescribed up-regulated genes in durum wheat, among these, 7 are up-regulated by heat, 8 by drought stress, 15 by combined heat and drought stress, 4 are up-regulated by both heat and combined stress, and 3 by both drought and combined stress. The functional characterization of these genes will provide new data that could help the developing of strategies aimed at improving durum wheat tolerance to field stress.

  20. The KASH protein Kms2 coordinates mitotic remodeling of the spindle pole body.

    PubMed

    Wälde, Sarah; King, Megan C

    2014-08-15

    Defects in the biogenesis of the spindle pole body (SPB), the yeast centrosome equivalent, can lead to monopolar spindles and mitotic catastrophe. The KASH domain protein Kms2 and the SUN domain protein Sad1 colocalize within the nuclear envelope at the site of SPB attachment during interphase and at the spindle poles during mitosis in Schizosaccharomyces pombe. We show that Kms2 interacts with the essential SPB components Cut12 and Pcp1 and the Polo kinase Plo1. Depletion of Kms2 delays mitotic entry and leads to defects in the insertion of the SPB into the nuclear envelope, disrupting stable bipolar spindle formation. These effects are mediated in part by a delay in the recruitment of Plo1 to the SPB at mitotic entry. Plo1 activity supports mitotic SPB remodeling by driving a burst of incorporation of Cut12 and Pcp1. Thus, a fission yeast SUN-KASH complex plays an important role in supporting the remodeling of the SPB at mitotic entry.

  1. The Yeast Snt2 Protein Coordinates the Transcriptional Response to Hydrogen Peroxide-Mediated Oxidative Stress

    PubMed Central

    Baker, Lindsey A.; Ueberheide, Beatrix M.; Dewell, Scott; Chait, Brian T.; Zheng, Deyou

    2013-01-01

    Regulation of gene expression is a vital part of the cellular stress response, yet the full set of proteins that orchestrate this regulation remains unknown. Snt2 is a Saccharomyces cerevisiae protein whose function has not been well characterized that was recently shown to associate with Ecm5 and the Rpd3 deacetylase. Here, we confirm that Snt2, Ecm5, and Rpd3 physically associate. We then demonstrate that cells lacking Rpd3 or Snt2 are resistant to hydrogen peroxide (H2O2)-mediated oxidative stress and use chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) to show that Snt2 and Ecm5 recruit Rpd3 to a small number of promoters and in response to H2O2, colocalize independently of Rpd3 to the promoters of stress response genes. By integrating ChIP-seq and expression analyses, we identify target genes that require Snt2 for proper expression after H2O2. Finally, we show that cells lacking Snt2 are also resistant to nutrient stress imparted by the TOR (target of rapamycin) pathway inhibitor rapamycin and identify a common set of genes targeted by Snt2 and Ecm5 in response to both H2O2 and rapamycin. Our results establish a function for Snt2 in regulating transcription in response to oxidative stress and suggest Snt2 may also function in multiple stress pathways. PMID:23878396

  2. Kinetic Definition of Protein Folding Transition State Ensembles and Reaction Coordinates

    PubMed Central

    Snow, Christopher D.; Rhee, Young Min; Pande, Vijay S.

    2006-01-01

    Using distributed molecular dynamics simulations we located four distinct folding transitions for a 39-residue ββαβ protein fold. To characterize the nature of each room temperature transition, we calculated the probability of transmission for 500 points along each free energy barrier. We introduced a method for determining transition states by employing the transmission probability, Ptrans, and determined which conformations were transition state ensemble members (Ptrans ≈ 0.5). The transmission probability may be used to characterize the barrier in several ways. For example, we ran simulations at 82°C, determined the change in Ptrans with temperature for all 2,000 conformations, and quantified Hammond behavior directly using Ptrans correlation. Additionally, we propose that diffusion along Ptrans may provide the configurational diffusion rate at the top of the barrier. Specifically, given a transition state conformation x0 with estimated Ptrans = 0.5, we selected a large set of subsequent conformations from independent trajectories, each exactly a small time δt after x0 (250 ps). Calculating Ptrans for the new trial conformations, we generated the P(Ptrans|δt = 250 ps) distribution that reflected diffusion. This approach provides a novel perspective on the diffusive nature of a protein folding transition and provides a framework for a quantitative study of activated relaxation kinetics. PMID:16617068

  3. Insecticide-Mediated Up-Regulation of Cytochrome P450 Genes in the Red Flour Beetle (Tribolium castaneum)

    PubMed Central

    Liang, Xiao; Xiao, Da; He, Yanping; Yao, Jianxiu; Zhu, Guonian; Zhu, Kun Yan

    2015-01-01

    Some cytochrome P450 (CYP) genes are known for their rapid up-regulation in response to insecticide exposures in insects. To date, however, limited information is available with respect to the relationships among the insecticide type, insecticide concentration, exposure duration and the up-regulated CYP genes. In this study, we examined the transcriptional response of eight selected CYP genes, including CYP4G7, CYP4Q4, CYP4BR3, CYP12H1, CYP6BK11, CYP9D4, CYP9Z5 and CYP345A1, to each of four insecticides in the red flour beetle, Tribolium castaneum. Reverse transcription quantitative PCR (RT-qPCR) revealed that CYP4G7 and CYP345A1 can be significantly up-regulated by cypermethrin (1.97- and 2.06-fold, respectively), permethrin (2.00- and 2.03-fold) and lambda-cyhalothrin (1.73- and 1.81-fold), whereas CYP4BR3 and CYP345A1 can be significantly up-regulated by imidacloprid (1.99- and 1.83-fold) when 20-day larvae were exposed to each of these insecticides at the concentration of LC20 for 24 h. Our studies also showed that similar levels of up-regulation can be achieved for CYP4G7, CYP4BR3 and CYP345A1 by cypermethrin, permethrin, lambda-cyhalothrin or imidacloprid with approximately one fourth of LC20 in 6 h. Our study demonstrated that up-regulation of these CYP genes was rapid and only required low concentrations of insecticides, and the up-regulation not only depended on the CYP genes but also the type of insecticides. Our results along with those from previous studies also indicated that there were no specific patterns for predicting the up-regulation of specific CYP gene families based on the insecticide classification. PMID:25607733

  4. Insecticide-mediated up-regulation of cytochrome P450 genes in the red flour beetle (Tribolium castaneum).

    PubMed

    Liang, Xiao; Xiao, Da; He, Yanping; Yao, Jianxiu; Zhu, Guonian; Zhu, Kun Yan

    2015-01-19

    Some cytochrome P450 (CYP) genes are known for their rapid up-regulation in response to insecticide exposures in insects. To date, however, limited information is available with respect to the relationships among the insecticide type, insecticide concentration, exposure duration and the up-regulated CYP genes. In this study, we examined the transcriptional response of eight selected CYP genes, including CYP4G7, CYP4Q4, CYP4BR3, CYP12H1, CYP6BK11, CYP9D4, CYP9Z5 and CYP345A1, to each of four insecticides in the red flour beetle, Tribolium castaneum. Reverse transcription quantitative PCR (RT-qPCR) revealed that CYP4G7 and CYP345A1 can be significantly up-regulated by cypermethrin (1.97- and 2.06-fold, respectively), permethrin (2.00- and 2.03-fold) and lambda-cyhalothrin (1.73- and 1.81-fold), whereas CYP4BR3 and CYP345A1 can be significantly up-regulated by imidacloprid (1.99- and 1.83-fold) when 20-day larvae were exposed to each of these insecticides at the concentration of LC20 for 24 h. Our studies also showed that similar levels of up-regulation can be achieved for CYP4G7, CYP4BR3 and CYP345A1 by cypermethrin, permethrin, lambda-cyhalothrin or imidacloprid with approximately one fourth of LC20 in 6 h. Our study demonstrated that up-regulation of these CYP genes was rapid and only required low concentrations of insecticides, and the up-regulation not only depended on the CYP genes but also the type of insecticides. Our results along with those from previous studies also indicated that there were no specific patterns for predicting the up-regulation of specific CYP gene families based on the insecticide classification.

  5. A novel action mechanism for MPT0G013, a derivative of arylsulfonamide, inhibits tumor angiogenesis through up-regulation of TIMP3 expression.

    PubMed

    Wang, Chih-Ya; Liou, Jing-Ping; Tsai, An-Chi; Lai, Mei-Jung; Liu, Yi-Min; Lee, Hsueh-Yun; Wang, Jing-Chi; Pan, Shiow-Lin; Teng, Che-Ming

    2014-10-30

    Tissue inhibitors of metalloproteinases 3 (TIMP3) were originally characterized as inhibitors of matrix metalloproteinases (MMPs), acting as potent antiangiogenic proteins. In this study, we demonstrated that the arylsulfonamide derivative MPT0G013 has potent antiangiogenic activities in vitro and in vivo viainducing TIMP3 expression. Treatments with MPT0G013 significantly inhibited endothelial cell functions, such as cell proliferation, migration, and tube formation, as well as induced p21 and cell cycle arrest at the G0/G1 phase. Subsequent microarray analysis showed significant induction of TIMP3 gene expression by MPT0G013, and siRNA-mediated blockage of TIMP3 up-regulation abrogated the antiangiogenic activities of MPT0G013 and prevented inhibition of p-AKT and p-ERK proteins. Importantly, MPT0G013 exhibited antiangiogenic activities in in vivo Matrigel plug assays, inhibited tumor growth and up-regulated TIMP3 and p21 proteins in HCT116 mouse xenograft models. These data suggest potential therapeutic application of MPT0G013 for angiogenesis-related diseases such as cancer.

  6. Coordinated Changes in Gene Expression Throughout Encystation of Giardia intestinalis

    PubMed Central

    Einarsson, Elin; Troell, Karin; Hoeppner, Marc P.; Grabherr, Manfred; Ribacke, Ulf; Svärd, Staffan G.

    2016-01-01

    Differentiation into infectious cysts through the process of encystation is crucial for transmission and survival of the intestinal protozoan parasite Giardia intestinalis. Hitherto the majority of studies have focused on the early events, leaving late encystation poorly defined. In order to further study encystation, focusing on the later events, we developed a new encystation protocol that generates a higher yield of mature cysts compared to standard methods. Transcriptome changes during the entire differentiation from trophozoites to cysts were thereafter studied using RNA sequencing (RNA-seq). A high level of periodicity was observed for up- and down-regulated genes, both at the level of the entire transcriptome and putative regulators. This suggests the trajectory of differentiation to be coordinated through developmentally linked gene regulatory activities. Our study identifies a core of 13 genes that are consistently up-regulated during initial encystation. Of these, two constitute previously uncharacterized proteins that we were able to localize to a new type of encystation-specific vesicles. Interestingly, the largest transcriptional changes were seen in the late phase of encystation with the majority of the highly up-regulated genes encoding hypothetical proteins. Several of these were epitope-tagged and localized to further characterize these previously unknown genetic components of encystation and possibly excystation. Finally, we also detected a switch of variant specific surface proteins (VSPs) in the late phase of encystation. This occurred at the same time as nuclear division and DNA replication, suggesting a potential link between the processes. PMID:27015092

  7. Glucocorticoids and protein kinase A coordinately modulate transcription factor recruitment at a glucocorticoid-responsive unit.

    PubMed Central

    Espinás, M L; Roux, J; Pictet, R; Grange, T

    1995-01-01

    The rat tyrosine aminotransferase gene is a model system to study transcriptional regulation by glucocorticoid hormones. We analyzed transcription factor binding to the tyrosine aminotransferase gene glucocorticoid-responsive unit (GRU) at kb -2.5, using in vivo footprinting studies with both dimethyl sulfate and DNase I. At this GRU, glucocorticoid activation triggers a disruption of the nucleosomal structure. We show here that various regulatory pathways affect transcription factor binding to this GRU. The binding differs in two closely related glucocorticoid-responsive hepatoma cell lines. In line H4II, glucocorticoid induction promotes the recruitment of hepatocyte nuclear factor 3 (HNF3), presumably through the nucleosomal disruption. However, the footprint of the glucocorticoid receptor (GR) is not visible, even though a regular but transient interaction of the GR is necessary to maintain HNF3 binding. In contrast, in line FTO2B, HNF3 binds to the GRU in the absence of glucocorticoids and nucleosomal disruption, showing that a "closed" chromatin conformation does not repress the binding of certain transcription factors in a uniform manner. In FTO2B cells, the footprint of the GR is detectable, but this requires the activation of protein kinase A. In addition, protein kinase A stimulation also improves the recruitment of HNF3 independently of glucocorticoids and enhances the glucocorticoid response mediated by this GRU in an HNF3-dependent manner. In conclusion, the differences in the behavior of this regulatory sequence in the two cell lines show that various regulatory pathways are integrated at this GRU through modulation of interrelated events: transcription factor binding to DNA and nucleosomal disruption. PMID:7565684

  8. Ribosomal protein uS19 mutants reveal its role in coordinating ribosome structure and function

    PubMed Central

    Bowen, Alicia M; Musalgaonkar, Sharmishtha; Moomau, Christine A; Gulay, Suna P; Mirvis, Mary; Dinman, Jonathan D

    2015-01-01

    Prior studies identified allosteric information pathways connecting functional centers in the large ribosomal subunit to the decoding center in the small subunit through the B1a and B1b/c intersubunit bridges in yeast. In prokaryotes a single SSU protein, uS13, partners with H38 (the A-site finger) and uL5 to form the B1a and B1b/c bridges respectively. In eukaryotes, the SSU component was split into 2 separate proteins during the course of evolution. One, also known as uS13, participates in B1b/c bridge with uL5 in eukaryotes. The other, called uS19 is the SSU partner in the B1a bridge with H38. Here, polyalanine mutants of uS19 involved in the uS19/uS13 and the uS19/H38 interfaces were used to elucidate the important amino acid residues involved in these intersubunit communication pathways. Two key clusters of amino acids were identified: one located at the junction between uS19 and uS13, and a second that appears to interact with the distal tip of H38. Biochemical analyses reveal that these mutations shift the ribosomal rotational equilibrium toward the unrotated state, increasing ribosomal affinity for tRNAs in the P-site and for ternary complex in the A-site, and inhibit binding of the translocase, eEF2. These defects in turn affect specific aspects of translational fidelity. These findings suggest that uS19 plays a critical role as a conduit of information exchange between the large and small ribosomal subunits directly through the B1a, and indirectly through the B1b/c bridges. PMID:26824029

  9. Integrin αDβ2, an adhesion receptor up-regulated on macrophage foam cells, exhibits multiligand-binding properties

    PubMed Central

    Yakubenko, Valentin P.; Yadav, Satya P.; Ugarova, Tatiana P.

    2006-01-01

    Integrin αDβ2, the most recently discovered member of the β2 subfamily of integrin adhesion receptors, is up-regulated on macrophage foam cells. Although other members of the subfamily have been subjects of extensive research, the recognition specificity and the molecular basis for αDβ2 ligand binding remain unknown. Based on the high extent of structural homology between αDβ2 and the major myeloid-cell-specific integrin αMβ2 (Mac-1), noted for its capacity to bind multiple ligands, we considered that the 2 integrins have similar recognition specificity. In this study, using recombinant and natural αDβ2-expressing cells, we demonstrate that αDβ2 supports adhesion and migration to many extracellular matrix proteins in a fashion similar to αMβ2. Consistent with these data, the recombinant αDI-domain of the receptor bound selected ligands. The binding was activation-dependent because the αDI-domain with its C-terminal α7 helix truncated, but not the form with the C-terminal part extended, bound ligands. When the αDI-domain segment Lys244-Lys260 (highly homologous to its αMI-domain counterpart Lys245-Arg261 responsible for αMβ2 multiligand-binding properties) was inserted into the mono-specific αLI-domain, the chimeric protein bound many ligands with affinities similar to those of wild-type αDI-domain. These results establish integrin αDβ2 as a multiligand receptor and indicate that the mechanism whereby αDβ2 exhibits broad ligand specificity resembles that used by αMβ2, the most promiscuous member of the integrin family. PMID:16239428

  10. Increased NF-κB signalling up-regulates BACE1 expression and its therapeutic potential in Alzheimer's disease.

    PubMed

    Chen, Chia-Hsiung; Zhou, Weihui; Liu, Shengchun; Deng, Yu; Cai, Fang; Tone, Masahide; Tone, Yukiko; Tong, Yigang; Song, Weihong

    2012-02-01

    Elevated levels of β-site APP cleaving enzyme 1 (BACE1) were found in the brain of some sporadic Alzheimer's disease (AD) patients; however, the underlying mechanism is unknown. BACE1 cleaves β-amyloid precursor protein (APP) to generate amyloid β protein (Aβ), a central component of neuritic plaques in AD brains. Nuclear factor-kappa B (NF-κB) signalling plays an important role in gene regulation and is implicated in inflammation, oxidative stress and apoptosis. In this report we found that both BACE1 and NF-κB p65 levels were significantly increased in the brains of AD patients. Two functional NF-κB-binding elements were identified in the human BACE1 promoter region. We found that NF-κB p65 expression resulted in increased BACE1 promoter activity and BACE1 transcription, while disruption of NF-κB p65 decreased BACE1 gene expression in p65 knockout (RelA-knockout) cells. In addition, NF-κB p65 expression leads to up-regulated β-secretase cleavage and Aβ production, while non-steroidal anti-inflammatory drugs (NSAIDs) inhibited BACE1 transcriptional activation induced by strong NF-κB activator tumour necrosis factor-alpha (TNF-α). Taken together, our results clearly demonstrate that NF-κB signalling facilitates BACE1 gene expression and APP processing, and increased BACE1 expression mediated by NF-κB signalling in the brain could be one of the novel molecular mechanisms underlying the development of AD in some sporadic cases. Furthermore, NSAIDs could block the inflammation-induced BACE1 transcription and Aβ production. Our study suggests that inhibition of NF-κB-mediated BACE1 expression may be a valuable drug target for AD therapy.

  11. Isoflurane Preconditioning Induces Neuroprotection by Up-Regulation of TREK1 in a Rat Model of Spinal Cord Ischemic Injury

    PubMed Central

    Wang, Kun; Kong, Xiangang

    2016-01-01

    This study aimed to explore the neuroprotection and mechanism of isoflurane on rats with spinal cord ischemic injury. Total 40 adult male Sprague-Dawley rats were divided into the four groups (n=10). Group A was sham-operation group; group B was ischemia group; group C was isoflurane preconditioning group; group D was isoflurane preconditioning followed by ischemia treatment group. Then the expressions of TWIK-related K+ channel 1 (TREK1) in the four groups were detected by immunofluorescent assay, real time-polymerase chain reactions (RT-PCR) and western blot. The primary neurons of rats were isolated and cultured under normal and hypoxic conditions. Besides, the neurons under two conditions were transfected with green fluorescent protein (GFP)-TREK1 and lentivirual to overexpress and silence TREK1. Additionally, the neurons were treated with isoflurane or not. Then caspase-3 activity and cell cycle of neurons under normal and hypoxic conditions were detected. Furthermore, nicotinamide adenine dinucleotide hydrate (NADH) was detected using NAD+/NADH quantification colorimetric kit. Results showed that the mRNA and protein expressions of TREK1 increased significantly in group C and D. In neurons, when TREK1 silenced, isoflurane treatment improved the caspase-3 activity. In hypoxic condition, the caspase-3 activity and sub-G1 cell percentage significantly increased, however, when TREK1 overexpressed the caspase-3 activity and sub-G1 cell percentage decreased significantly. Furthermore, both isoflurane treatment and overexpression of TREK1 significantly decreased NADH. In conclusion, isoflurane-induced neuroprotection in spinal cord ischemic injury may be associated with the up-regulation of TREK1. PMID:27469140

  12. Recurrent MALAT1-GLI1 oncogenic fusion and GLI1 up-regulation define a subset of plexiform fibromyxoma.

    PubMed

    Spans, Lien; Fletcher, Christopher Dm; Antonescu, Cristina R; Rouquette, Alexandre; Coindre, Jean-Michel; Sciot, Raf; Debiec-Rychter, Maria

    2016-07-01

    Plexiform fibromyxomas are rare neoplasms, being officially recognized as a distinct entity among benign mesenchymal gastric tumours in the 2010 WHO Classification of Tumours of the Digestive System. Characteristically, these tumours have a multinodular/plexiform growth pattern, and histologically contain variably cellular areas of bland myofibroblastic-type spindle cells embedded in an abundant myxoid matrix, rich in capillary-type vessels. As yet, the molecular and/or genetic features of these tumours are unknown. Here we describe a recurrent translocation, t(11;12)(q11;q13), involving the long non-coding gene metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and the gene glioma-associated oncogene homologue 1 (GLI1) in a subgroup of these tumours. The presence of the fusion transcript in our index case was confirmed using polymerase chain reaction (PCR) on genomic DNA, followed by Sanger sequencing. We showed that the truncated GLI1 protein is overexpressed and retains its capacity to transcriptionally activate its target genes. A specific FISH assay was developed to detect the novel MALAT1-GLI1 translocation in formalin-fixed, paraffin-embedded (FFPE) material. This resulted in the identification of two additional cases with this fusion and two cases with polysomy of the GLI1 gene. Finally, immunohistochemistry revealed that the GLI1 protein is exclusively overexpressed in those cases that harbour GLI1/12q13 genomic alterations. In conclusion, overexpression of GLI1 through a recurrent MALAT1-GLI1 translocation or GLI1 up-regulation delineates a pathogenically distinct subgroup of plexiform fibromyxomas with activation of the Sonic Hedgehog signalling pathway. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:27101025

  13. NOS1AP modulates intracellular Ca2+ in cardiac myocytes and is up-regulated in dystrophic cardiomyopathy

    PubMed Central

    Treuer, Adriana V; Gonzalez, Daniel R

    2014-01-01

    NOS1AP gene (nitric oxide synthase 1-adaptor protein) is strongly associated with abnormalities in the QT interval of the electrocardiogram and with sudden cardiac death. To determine the role of NOS1AP in the physiology of the cardiac myocyte, we assessed the impact of silencing NOS1AP, using siRNA, on [Ca2+]i transients in neonatal cardiomyocytes. In addition, we examined the co-localization of NOS1AP with cardiac ion channels, and finally, evaluated the expression of NOS1AP in a mouse model of dystrophic cardiomyopathy. Using siRNA, NOS1AP levels were reduced to ~30% of the control levels (p<0.05). NOS1AP silencing in cardiac myocytes reduced significantly the amplitude of electrically evoked calcium transients (p<0.05) and the degree of S-nitrosylation of the cells (p<0.05). Using confocal microscopy, we evaluated NOS1AP subcellular location and interactions with other proteins by co-localization analysis. NOS1AP showed a high degree of co-localization with the L-type calcium channel and the inwardly rectifying potassium channel Kir3.1, a low degree of co-localization with the ryanodine receptor (RyR2) and alfa-sarcomeric actin and no co-localization with connexin 43, suggesting functionally relevant interactions with the ion channels that regulate the action potential duration. Finally, using immunofluorescence and Western blotting, we observed that in mice with dystrophic cardiomyopathy, NOS1AP was significantly up-regulated (p<0.05). These results suggest for a role of NOS1AP on cardiac arrhythmias, acting on the L-type calcium channel, and potassium channels, probably through S-nitrosylation. PMID:24665357

  14. Recurrent MALAT1-GLI1 oncogenic fusion and GLI1 up-regulation define a subset of plexiform fibromyxoma.

    PubMed

    Spans, Lien; Fletcher, Christopher Dm; Antonescu, Cristina R; Rouquette, Alexandre; Coindre, Jean-Michel; Sciot, Raf; Debiec-Rychter, Maria

    2016-07-01

    Plexiform fibromyxomas are rare neoplasms, being officially recognized as a distinct entity among benign mesenchymal gastric tumours in the 2010 WHO Classification of Tumours of the Digestive System. Characteristically, these tumours have a multinodular/plexiform growth pattern, and histologically contain variably cellular areas of bland myofibroblastic-type spindle cells embedded in an abundant myxoid matrix, rich in capillary-type vessels. As yet, the molecular and/or genetic features of these tumours are unknown. Here we describe a recurrent translocation, t(11;12)(q11;q13), involving the long non-coding gene metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and the gene glioma-associated oncogene homologue 1 (GLI1) in a subgroup of these tumours. The presence of the fusion transcript in our index case was confirmed using polymerase chain reaction (PCR) on genomic DNA, followed by Sanger sequencing. We showed that the truncated GLI1 protein is overexpressed and retains its capacity to transcriptionally activate its target genes. A specific FISH assay was developed to detect the novel MALAT1-GLI1 translocation in formalin-fixed, paraffin-embedded (FFPE) material. This resulted in the identification of two additional cases with this fusion and two cases with polysomy of the GLI1 gene. Finally, immunohistochemistry revealed that the GLI1 protein is exclusively overexpressed in those cases that harbour GLI1/12q13 genomic alterations. In conclusion, overexpression of GLI1 through a recurrent MALAT1-GLI1 translocation or GLI1 up-regulation delineates a pathogenically distinct subgroup of plexiform fibromyxomas with activation of the Sonic Hedgehog signalling pathway. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  15. Ethanol up-regulates nucleus accumbens neuronal activity dependent pentraxin (Narp): implications for alcohol-induced behavioral plasticity.

    PubMed

    Ary, Alexis W; Cozzoli, Debra K; Finn, Deborah A; Crabbe, John C; Dehoff, Marlin H; Worley, Paul F; Szumlinski, Karen K

    2012-06-01

    Neuronal activity dependent pentraxin (Narp) interacts with α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) glutamate receptors to facilitate excitatory synapse formation by aggregating them at established synapses. Alcohol is well-characterized to influence central glutamatergic transmission, including AMPA receptor function. Herein, we examined the influence of injected and ingested alcohol upon Narp protein expression, as well as basal Narp expression in mouse lines selectively bred for high blood alcohol concentrations under limited access conditions. Alcohol up-regulated accumbens Narp levels, concomitant with increases in levels of the GluR1 AMPA receptor subunit. However, accumbens Narp or GluR1 levels did not vary as a function of selectively bred genotype. We next employed a Narp knock-out (KO) strategy to begin to understand the behavioral relevance of alcohol-induced changes in protein expression in several assays of alcohol reward. Compared to wild-type mice, Narp KO animals: fail to escalate daily intake of high alcohol concentrations under free-access conditions; shift their preference away from high alcohol concentrations with repeated alcohol experience; exhibit a conditioned place-aversion in response to the repeated pairing of 3 g/kg alcohol with a distinct environment and fail to exhibit alcohol-induced locomotor hyperactivity following repeated alcohol treatment. Narp deletion did not influence the daily intake of either food or water, nor did it alter any aspect of spontaneous or alcohol-induced motor activity, including the development of tolerance to its motor-impairing effects with repeated treatment. Taken together, these data indicate that Narp induction, and presumably subsequent aggregation of AMPA receptors, may be important for neuroplasticity within limbic subcircuits mediating or maintaining the rewarding properties of alcohol.

  16. Isoflurane Preconditioning Induces Neuroprotection by Up-Regulation of TREK1 in a Rat Model of Spinal Cord Ischemic Injury.

    PubMed

    Wang, Kun; Kong, Xiangang

    2016-09-01

    This study aimed to explore the neuroprotection and mechanism of isoflurane on rats with spinal cord ischemic injury. Total 40 adult male Sprague-Dawley rats were divided into the four groups (n=10). Group A was sham-operation group; group B was ischemia group; group C was isoflurane preconditioning group; group D was isoflurane preconditioning followed by ischemia treatment group. Then the expressions of TWIK-related K⁺ channel 1 (TREK1) in the four groups were detected by immunofluorescent assay, real time-polymerase chain reactions (RT-PCR) and western blot. The primary neurons of rats were isolated and cultured under normal and hypoxic conditions. Besides, the neurons under two conditions were transfected with green fluorescent protein (GFP)-TREK1 and lentivirual to overexpress and silence TREK1. Additionally, the neurons were treated with isoflurane or not. Then caspase-3 activity and cell cycle of neurons under normal and hypoxic conditions were detected. Furthermore, nicotinamide adenine dinucleotide hydrate (NADH) was detected using NAD+/NADH quantification colorimetric kit. Results showed that the mRNA and protein expressions of TREK1 increased significantly in group C and D. In neurons, when TREK1 silenced, isoflurane treatment improved the caspase-3 activity. In hypoxic condition, the caspase-3 activity and sub-G1 cell percentage significantly increased, however, when TREK1 overexpressed the caspase-3 activity and sub-G1 cell percentage decreased significantly. Furthermore, both isoflurane treatment and overexpression of TREK1 significantly decreased NADH. In conclusion, isoflurane-induced neuroprotection in spinal cord ischemic injury may be associated with the up-regulation of TREK1. PMID:27469140

  17. Electrical stimulation induces calcium-dependent up-regulation of neuregulin-1β in dystrophic skeletal muscle cell lines.

    PubMed

    Juretić, Nevenka; Jorquera, Gonzalo; Caviedes, Pablo; Jaimovich, Enrique; Riveros, Nora

    2012-01-01

    Duchenne muscular dystrophy (DMD) is a neuromuscular disease originated by reduced or no expression of dystrophin, a cytoskeletal protein that provides structural integrity to muscle fibres. A promising pharmacological treatment for DMD aims to increase the level of a structural dystrophin homolog called utrophin. Neuregulin-1 (NRG-1), a growth factor that potentiates myogenesis, induces utrophin expression in skeletal muscle cells. Microarray analysis of total gene expression allowed us to determine that neuregulin-1β (NRG-1β) is one of 150 differentially expressed genes in electrically stimulated (400 pulses, 1 ms, 45 Hz) dystrophic human skeletal muscle cells (RCDMD). We investigated the effect of depolarization, and the involvement of intracellular Ca(2+) and PKC isoforms on NRG-1β expression in dystrophic myotubes. Electrical stimulation of RCDMD increased NRG-1β mRNA and protein levels, and mRNA enhancement was abolished by actinomycin D. NRG-1β transcription was inhibited by BAPTA-AM, an intracellular Ca(2+) chelator, and by inhibitors of IP(3)-dependent slow Ca(2+) transients, like 2-APB, Ly 294002 and Xestospongin B. Ryanodine, a fast Ca(2+) signal inhibitor, had no effect on electrical stimulation-induced expression. BIM VI (general inhibitor of PKC isoforms) and Gö 6976 (specific inhibitor of Ca(2+)-dependent PKC isoforms) abolished NRG-1β mRNA induction. Our results suggest that depolarization induced slow Ca(2+) signals stimulate NRG-1β transcription in RCDMD cells, and that Ca(2+)-dependent PKC isoforms are involved in this process. Based on utrophin's ability to partially compensate dystrophin disfunction, knowledge on the mechanism involved on NRG-1 up-regulation could be important for new therapeutic strategies design. PMID:22613991

  18. The mitochondrial uncoupler DNP triggers brain cell mTOR signaling network reprogramming and CREB pathway up-regulation.

    PubMed

    Liu, Dong; Zhang, Yongqing; Gharavi, Robert; Park, Hee Ra; Lee, Jaewon; Siddiqui, Sana; Telljohann, Richard; Nassar, Matthew R; Cutler, Roy G; Becker, Kevin G; Mattson, Mark P

    2015-08-01

    Mitochondrial metabolism is highly responsive to nutrient availability and ongoing activity in neuronal circuits. The molecular mechanisms by which brain cells respond to an increase in cellular energy expenditure are largely unknown. Mild mitochondrial uncoupling enhances cellular energy expenditure in mitochondria and can be induced with 2,4-dinitrophenol (DNP), a proton ionophore previously used for weight loss. We found that DNP treatment reduces mitochondrial membrane potential, increases intracellular Ca(2+) levels and reduces oxidative stress in cerebral cortical neurons. Gene expression profiling of the cerebral cortex of DNP-treated mice revealed reprogramming of signaling cascades that included suppression of the mammalian target of rapamycin (mTOR) and insulin--PI3K - MAPK pathways, and up-regulation of tuberous sclerosis complex 2, a negative regulator of mTOR. Genes encoding proteins involved in autophagy processes were up-regulated in response to DNP. CREB (cAMP-response element-binding protein) signaling, Arc and brain-derived neurotrophic factor, which play important roles in synaptic plasticity and adaptive cellular stress responses, were up-regulated in response to DNP, and DNP-treated mice exhibited improved performance in a test of learning and memory. Immunoblot analysis verified that key DNP-induced changes in gene expression resulted in corresponding changes at the protein level. Our findings suggest that mild mitochondrial uncoupling triggers an integrated signaling response in brain cells characterized by reprogramming of mTOR and insulin signaling, and up-regulation of pathways involved in adaptive stress responses, molecular waste disposal, and synaptic plasticity. Physiological bioenergetic challenges such as exercise and fasting can enhance neuroplasticity and protect neurons against injury and neurodegeneration. Here, we show that the mitochondrial uncoupling agent 2,4-dinitrophenol (DNP) elicits adaptive signaling responses in the

  19. Substance P primes lipoteichoic acid- and Pam3CysSerLys4-mediated activation of human mast cells by up-regulating Toll-like receptor 2.

    PubMed

    Tancowny, Brian P; Karpov, Victor; Schleimer, Robert P; Kulka, Marianna

    2010-10-01

    Substance P (SP) is a neuropeptide with neuroimmunoregulatory activity that may play a role in susceptibility to infection. Human mast cells, which are important in innate immune responses, were analysed for their responses to pathogen-associated molecules via Toll-like receptors (TLRs) in the presence of SP. Human cultured mast cells (LAD2) were activated by SP and TLR ligands including lipopolysaccharide (LPS), Pam3CysSerLys4 (Pam3CSK4) and lipoteichoic acid (LTA), and mast cell leukotriene and chemokine production was assessed by enzyme-linked immunosorbent assay (ELISA) and gene expression by quantitative PCR (qPCR). Mast cell degranulation was determined using a β-hexosaminidase (β-hex) assay. SP treatment of LAD2 up-regulated mRNA for TLR2, TLR4, TLR8 and TLR9 while anti-immunoglobulin E (IgE) stimulation up-regulated expression of TLR4 only. Flow cytometry and western blot confirmed up-regulation of TLR2 and TLR8. Pretreatment of LAD2 with SP followed by stimulation with Pam3CSK4 or LTA increased production of leukotriene C4 (LTC(4) ) and interleukin (IL)-8 compared with treatment with Pam3CSK4 or LTA alone (>2-fold; P<0·01). SP alone activated 5-lipoxygenase (5-LO) nuclear translocation but also augmented Pam3CSK4 and LTA-mediated 5-LO translocation. Pam3CSK4, LPS and LTA did not induce LAD2 degranulation. SP primed LTA and Pam3CSK4-mediated activation of JNK, p38 and extracellular-signal-regulated kinase (ERK) and activated the nuclear translocation of c-Jun, nuclear factor (NF)-κB, activating transcription factor 2 (ATF-2) and cyclic-AMP-responsive element binding protein (CREB) transcription factors. Pretreatment with SP followed by LTA stimulation synergistically induced production of chemokine (C-X-C motif) ligand 8 (CXCL8)/IL-8, chemokine (C-C motif) ligand 2 (CCL2)/monocyte chemotactic protein 1 (MCP-1), tumour necrosis factor (TNF) and IL-6 protein. SP primes TLR2-mediated activation of human mast cells by up-regulating TLR expression and

  20. Prenatal Ethanol Exposure Up-Regulates the Cholesterol Transporters ATP-Binding Cassette A1 and G1 and Reduces Cholesterol Levels in the Developing Rat Brain

    PubMed Central

    Zhou, Chunyan; Chen, Jing; Zhang, Xiaolu; Costa, Lucio G.; Guizzetti, Marina

    2014-01-01

    Aims: Cholesterol plays a pivotal role in many aspects of brain development; reduced cholesterol levels during brain development, as a consequence of genetic defects in cholesterol biosynthesis, leads to severe brain damage, including microcephaly and mental retardation, both of which are also hallmarks of the fetal alcohol syndrome. We had previously shown that ethanol up-regulates the levels of two cholesterol transporters, ABCA1 (ATP binding cassette-A1) and ABCG1, leading to increased cholesterol efflux and decreased cholesterol content in astrocytes in vitro. In the present study we investigated whether similar effects could be seen in vivo. Methods: Pregnant Sprague-Dawley rats were fed liquid diets containing 36% of the calories from ethanol from gestational day (GD) 6 to GD 21. A pair-fed control groups and an ad libitum control group were included in the study. ABCA1 and ABCG1 protein expression and cholesterol and phospholipid levels were measured in the neocortex of female and male fetuses at GD 21. Results: Body weights were decreased in female fetuses as a consequence of ethanol treatments. ABCA1 and ABCG1 protein levels were increased, and cholesterol levels were decreased, in the neocortex of ethanol-exposed female, but not male, fetuses. Levels of phospholipids were unchanged. Control female fetuses fed ad libitum displayed an up-regulation of ABCA1 and a decrease in cholesterol content compared with pair-fed controls, suggesting that a compensatory up-regulation of cholesterol levels may occur during food restriction. Conclusion: Maternal ethanol consumption may affect fetal brain development by increasing cholesterol transporters’ expression and reducing brain cholesterol levels. PMID:25081040

  1. Copper deficiency alters cell bioenergetics and induces mitochondrial fusion through up-regulation of MFN2 and OPA1 in erythropoietic cells

    SciTech Connect

    Bustos, Rodrigo I.; Jensen, Erik L.; Ruiz, Lina M.; Rivera, Salvador; Ruiz, Sebastián; Simon, Felipe; Riedel, Claudia; Ferrick, David; Elorza, Alvaro A.

    2013-08-02

    Highlights: •In copper deficiency, cell proliferation is not affected. In turn, cell differentiation is impaired. •Enlarged mitochondria are due to up-regulation of MNF2 and OPA1. •Mitochondria turn off respiratory chain and ROS production. •Energy metabolism switch from mitochondria to glycolysis. -- Abstract: Copper is essential in cell physiology, participating in numerous enzyme reactions. In mitochondria, copper is a cofactor for respiratory complex IV, the cytochrome c oxidase. Low copper content is associated with anemia and the appearance of enlarged mitochondria in erythropoietic cells. These findings suggest a connection between copper metabolism and bioenergetics, mitochondrial dynamics and erythropoiesis, which has not been explored so far. Here, we describe that bathocuproine disulfonate-induced copper deficiency does not alter erythropoietic cell proliferation nor induce apoptosis. However it does impair erythroid differentiation, which is associated with a metabolic switch between the two main energy-generating pathways. That is, from mitochondrial function to glycolysis. Switching off mitochondria implies a reduction in oxygen consumption and ROS generation along with an increase in mitochondrial membrane potential. Mitochondrial fusion proteins MFN2 and OPA1 were up-regulated along with the ability of mitochondria to fuse. Morphometric analysis of mitochondria did not show changes in total mitochondrial biomass but rather bigger mitochondria because of increased fusion. Similar results were also obtained with human CD34+, which were induced to differentiate into red blood cells. In all, we have shown that adequate copper levels are important for maintaining proper mitochondrial function and for erythroid differentiation where the energy metabolic switch plus the up-regulation of fusion proteins define an adaptive response to copper deprivation to keep cells alive.

  2. Testosterone protects female embryonic heart H9c2 cells against severe metabolic stress by activating estrogen receptors and up-regulating IES SUR2B.

    PubMed

    Ballantyne, Thomas; Du, Qingyou; Jovanović, Sofija; Neemo, Andrew; Holmes, Robert; Sinha, Sharabh; Jovanović, Aleksandar

    2013-02-01

    A recent clinical study demonstrated that a testosterone supplementation improves functional capacity in elderly female patients suffering from heart failure. These findings prompted us to consider possible mechanisms of testosterone-induced cardioprotection in females. To address this question we have used a pure female population of rat heart embryonic H9c2 cells. Pre-treatment of cells with testosterone for 24h significantly increased survival of H9c2 cells exposed to 2,4-dinitrophenol (DNP), an inhibitor of oxidative phosphorylation. These cells expressed low level of androgen receptors and the effect of testosterone was not modified by hydroxyflutamide, an antagonist of androgen receptor. In contrast, cyclohexamide, an inhibitor of protein biosynthesis, and tamoxifene, a partial agonist of estrogen receptors, abolished cardioprotection afforded by testosterone. In addition, finasteride, an inhibitor of 5α-reductase, and anastrazole, an inhibitor of α-aromatase, also blocked testosterone-induced cytoprotection. Real time RT-PCR revealed that testosterone did not regulate the expression of nine subunits and accessory proteins of sarcolemmal ATP-sensitive K(+) (K(ATP)) channels. On the other hand, testosterone, as well as 17β-estradiol, up-regulated a putative mitochondrial K(ATP) channel subunit, mitochondrial sulfonylurea receptor 2B intraexonics splice variant (IES SUR2B), without affecting expression of IES SUR2A. Tamoxifene inhibited testosterone-induced up-regulation of IES SUR2B without affecting IES SUR2A. In conclusion, this study has shown that testosterone protect female embryonic heart H9c2 cells against severe metabolic stress by its conversion into metabolites that activate estrogen receptors and up-regulate IES SUR2B.

  3. Tissue-specific up-regulation of arginase I and II induced by p38 MAPK mediates endothelial dysfunction in type 1 diabetes mellitus

    PubMed Central

    Pernow, J; Kiss, A; Tratsiakovich, Y; Climent, B

    2015-01-01

    Background and Purpose Emerging evidence suggests a selective up-regulation of arginase I in diabetes causing coronary artery disease; however, the mechanisms behind this up-regulation are still unknown. Activated p38 MAPK has been reported to increase arginase II in various cardiovascular diseases. We therefore tested the role of p38 MAPK in the regulation of arginase I and II expression and its effect on endothelial dysfunction in diabetes mellitus. Experimental Approach Endothelial function was determined in septal coronary (SCA), left anterior descending coronary (LAD) and mesenteric (MA) arteries from healthy and streptozotocin-induced diabetic Wistar rats by wire myographs. Arginase activity and protein levels of arginase I, II, phospho-p38 MAPK and phospho-endothelial NOS (eNOS) (Ser1177) were determined in these arteries from diabetic and healthy rats treated with a p38 MAPK inhibitor in vivo. Key Results Diabetic SCA and MA displayed impaired endothelium-dependent relaxation, which was prevented by arginase and p38 MAPK inhibition while LAD relaxation was not affected. Arginase I, phospho-p38 MAPK and eNOS protein expression was increased in diabetic coronary arteries. In diabetic MA, however, increased expression of arginase II and phospho-p38 MAPK, increased arginase activity and decreased expression of eNOS were observed. All these effects were reversed by p38 MAPK inhibition. Conclusions and Implications Diabetes-induced activation of p38 MAPK causes endothelial dysfunction via selective up-regulation of arginase I expression in coronary arteries and arginase II expression in MA. Therefore, regional differences appear to exist in the arginase isoforms contributing to endothelial dysfunction in type 1 diabetes mellitus. PMID:26140333

  4. Antisense-mediated depletion of p300 in human cells leads to premature G1 exit and up-regulation of c-MYC.

    PubMed

    Kolli, S; Buchmann, A M; Williams, J; Weitzman, S; Thimmapaya, B

    2001-04-10

    The cAMP-response element-binding protein (CREB)-binding protein and p300 are two highly conserved transcriptional coactivators and histone acetyltransferases that integrate signals from diverse signal transduction pathways in the nucleus and also link chromatin remodeling with transcription. In this report, we have examined the role of p300 in the control of the G(1) phase of the cell cycle in nontransformed immortalized human breast epithelial cells (MCF10A) and fibroblasts (MSU) by using adenovirus vectors expressing p300-specific antisense sequences. Quiescent MCF10A and MSU cells expressing p300-specific antisense sequences synthesized p300 at much reduced levels and exited G(1) phase without serum stimulation. These cells also showed an increase in cyclin A and cyclin A- and E-associated kinase activities characteristic of S phase induction. Further analysis of the p300-depleted quiescent MCF10A cells revealed a 5-fold induction of c-MYC and a 2-fold induction of c-JUN. A direct target of c-MYC, CAD, which is required for DNA synthesis, was also found to be up-regulated, indicating that up-regulation of c-MYC functionally contributed to DNA synthesis. Furthermore, S phase induction in p300-depleted cells was reversed when antisense c-MYC was expressed in these cells, indicating that up-regulation of c-MYC may directly contribute to S phase induction. Adenovirus E1A also induced DNA synthesis and increased the levels of c-MYC and c-JUN in serum-starved MCF10A cells in a p300-dependent manner. Our results suggest an important role of p300 in cell cycle regulation at G(1) and raise the possibility that p300 may negatively regulate early response genes, including c-MYC and c-JUN, thereby preventing DNA synthesis in quiescent cells.

  5. Up-regulation of MicroRNA 146b is Associated with Myelofibrosis in Myeloproliferative Neoplasms.

    PubMed

    Ha, Jung-Sook; Jung, Hye-Ra

    2015-01-01

    In this study, our goal was to evaluate whether the expressions of microRNA (miR)-150, miR-146b, miR-31 and miR-95 demonstrate primary myelofibrosis (PMF) specificity, associations with fibrosis grade, hematologic phenotypes, or myeloproliferative neoplasm (MPN)-associated mutations. A total of 51 formalin-fixed and paraffin-embedded bone marrow MPN samples, including 15 polycythemia vera (PV), 26 essential thrombocythemia (ET), and 10 PMF, and 24 normal controls were included. The expression of microRNA (miRNA) was detected by quantitative real-time polymerase chain reaction using miRNA specific primers. RNU6-2 was analyzed for all samples as endogenous control for relative quantification. Information for fibrosis, hematologic parameters, Janus kinase 2 (JAK2) V617F, and calreticulin (CALR) mutations was obtained from medical records. Significant increment of miR-146b was detected in PMF compared to normal controls (P=0.008). Moreover, expression of miR-146b tended to increase according to increment of fibrosis grade, and patients with myelofibrosis (MF) grade 3 showed significantly higher expression than patients with MF 0 to 2 (P=0.022, 0.001 and 0.013, respectively) or normal controls (P<0.001). The expression of miR-31 also showed tendency to increase following fibrosis and miR-150 showed up-regulated expression in ET (P=0.015) compared to normal control. There was no relationship between miRNA expression and hematologic indices except miR-95 showed negative correlation with platelet count (P=0.024). There was no significant correlation between miRNA expression and JAK2 V617F or CALR mutation. Up-regulation of miR-146b could be used as a fibrosis-indicating marker and might be helpful in the study of fibrotic mechanism in MPN, as well as other fibrotic diseases. PMID:26116595

  6. One Octarepeate Expansion to the Human Prion Protein Alters Both the Zn2plus and Cu2plus Coordination Environments within the Octarepeate Domain

    SciTech Connect

    J Shearer; K Rosenkoetter; P Callan; C Pham

    2011-12-31

    The influence of a single octarepeat expansion on the Cu{sup II} and Zn{sup II} coordination environments within the octarepeat domain of the human prion protein is examined. Using X-ray absorption spectroscopy and diethyl pyrocarbonate labeling studies, we find that at low copper concentrations the 'normal' octarepeat domain (four PHGGGWGQ repeats) coordinates Zn{sup II} in an (N/O){sub 6} coordination environment with two histidine residues and Cu{sup II} in a redox-inactive (N/O){sub 4} coordination environment using one imidazole residue. Expansion of the octarepeat region by one repeat (five PHGGGWGQ repeats) yields a three-histidine (N/O){sub 6} coordination environment for Zn{sup II} and a two-histidine (N/O){sub 4} coordination environment for Cu{sup II} at low copper concentrations. This Cu{sup II}[(N/O){sub 2}-histidine{sub 2}] coordination motif is redox-active and capable of generating H{sub 2}O{sub 2} under reducing aerobic conditions.

  7. A few shared up-regulated genes may influence conidia to yeast transformation in dimorphic fungal pathogens.

    PubMed

    Kirkland, Theo N

    2016-08-01

    The small number of fungi that commonly cause disease in normal people share the capacity to grow as mycelia in the soil at 25°C and as yeast (or spherules) in mammals at 37°C. This remarkable conversion has long been a topic of interest in medical mycology. The conidia to yeast conversion has been studied by transcription profiling in several fungal species, including Histoplasma capsulatum, Paracoccidioides brasiliensis, Coccidioides spp., Blastomyces dermatitidis, and Talaromyces marneffei One limitation of transcriptional profiling is determining which genes are involved in the process of conversion to yeast as opposed to a result of conversion to yeast. If there are genes that are up-regulated in the yeast phase of more than one dimorphic, pathogenic fungus they might be required for conversion to yeast (or spherules). To address this issue, 24 up-regulated genes common to Coccidioides spp spherules and H. capsulatum yeasts were identified. Four homologs of these genes were also found in P. brasiliensis, B. dermatitidis or T. marneffei genes that were up-regulated in yeast. 4-hydroxyphenylpurvate dioxygenase, a gene involved in tyrosine metabolism and melanin synthesis that has been shown to be required for yeast conversion, is conserved and up-regulated in yeast in all five species. Another up-regulated gene that is conserved in all five species is a MFS sugar porter. These results suggest that a minority of up-regulated yeast (or spherule) genes are conserved across species and raises the possibility that conserved up-regulated genes may be of special interest for differentiation of mycelium into yeast.

  8. A few shared up-regulated genes may influence conidia to yeast transformation in dimorphic fungal pathogens.

    PubMed

    Kirkland, Theo N

    2016-08-01

    The small number of fungi that commonly cause disease in normal people share the capacity to grow as mycelia in the soil at 25°C and as yeast (or spherules) in mammals at 37°C. This remarkable conversion has long been a topic of interest in medical mycology. The conidia to yeast conversion has been studied by transcription profiling in several fungal species, including Histoplasma capsulatum, Paracoccidioides brasiliensis, Coccidioides spp., Blastomyces dermatitidis, and Talaromyces marneffei One limitation of transcriptional profiling is determining which genes are involved in the process of conversion to yeast as opposed to a result of conversion to yeast. If there are genes that are up-regulated in the yeast phase of more than one dimorphic, pathogenic fungus they might be required for conversion to yeast (or spherules). To address this issue, 24 up-regulated genes common to Coccidioides spp spherules and H. capsulatum yeasts were identified. Four homologs of these genes were also found in P. brasiliensis, B. dermatitidis or T. marneffei genes that were up-regulated in yeast. 4-hydroxyphenylpurvate dioxygenase, a gene involved in tyrosine metabolism and melanin synthesis that has been shown to be required for yeast conversion, is conserved and up-regulated in yeast in all five species. Another up-regulated gene that is conserved in all five species is a MFS sugar porter. These results suggest that a minority of up-regulated yeast (or spherule) genes are conserved across species and raises the possibility that conserved up-regulated genes may be of special interest for differentiation of mycelium into yeast. PMID:27118798

  9. TNF-alpha increases ubiquitin-conjugating activity in skeletal muscle by up-regulating UbcH2/E220k

    NASA Technical Reports Server (NTRS)

    Li, Yi-Ping; Lecker, Stewart H.; Chen, Yuling; Waddell, Ian D.; Goldberg, Alfred L.; Reid, Michael B.

    2003-01-01

    In some inflammatory diseases, TNF-alpha is thought to stimulate muscle catabolism via an NF-kappaB-dependent process that increases ubiquitin conjugation to muscle proteins. The transcriptional mechanism of this response has not been determined. Here we studied the potential role of UbcH2, a ubiquitin carrier protein and homologue of murine E220k. We find that UbcH2 is constitutively expressed by human skeletal and cardiac muscles, murine limb muscle, and cultured myotubes. TNF-alpha stimulates UbcH2 expression in mouse limb muscles in vivo and in cultured myotubes. The UbcH2 promoter region contains a functional NF-kappaB binding site; NF-kappaB binding to this sequence is increased by TNF-alpha stimulation. A dominant negative inhibitor of NF-kappaB activation blocks both UbcH2 up-regulation and the increase in ubiquitin-conjugating activity stimulated by TNF-alpha. In extracts from TNF-alpha-treated myotubes, ubiquitin-conjugating activity is limited by UbcH2 availability; activity is inhibited by an antiserum to UbcH2 or a dominant negative mutant of UbcH2 and is enhanced by wild-type UbcH2. Thus, UbcH2 up-regulation is a novel response to TNF-alpha/NF-kappaB signaling in skeletal muscle that appears to be essential for the increased ubiquitin conjugation induced by this cytokine.

  10. Membrane lipid modification by polyunsaturated fatty acids sensitizes oligodendroglial OLN-93 cells against oxidative stress and promotes up-regulation of heme oxygenase-1 (HSP32).

    PubMed

    Brand, Annette; Bauer, Nina G; Hallott, Amanda; Goldbaum, Olaf; Ghebremeskel, Kebreab; Reifen, Ram; Richter-Landsberg, Christiane

    2010-04-01

    Polyunsaturated fatty acids (PUFA) are highly abundant in brain tissue, and docosahexaenoic acid (DHA) might protect cells from oxidative stress (OS) during inflammation and demyelinating disorders, but also might exert pro-oxidant effects. Here we investigated if PUFA supplements lead to heat shock protein induction, altered cell survival properties and stress responses to OS exerted by hydrogen peroxide in oligodendroglial OLN-93 cells. The data show that supplements of various fatty acids (FA) with 18-22 carbons chain length and 2-6 double bonds led to PUFA enrichment in cellular membranes. Depending on the degree of desaturation, FA-supplements caused the up-regulation of heme oxygenase-1 (HSP32), a stress protein inducible by OS, and an increase in sensitivity to hydrogen peroxide-treatment. DHA, with the highest number of double bonds, was most effective. Co-treatment with DHA and the lipophilic vitamin E analogue alpha-tocopherol, suppressed heme oxygenase-1 up-regulation and cell survival was restored. Analysis of the lipid profile demonstrates that alpha-tocopherol not only has antioxidant capacities, but also directly modified the PUFA profile in cell membranes. Enrichment with higher omega-3, -6 and -9 PUFA and an increase in the biosynthesis rate of very long chain fatty acids, mainly changed the FA profile of ethanolamine and serine phosphoglycerides.

  11. Up-regulation of carbon metabolism-related glyoxylate cycle and toxin production in Beauveria bassiana JEF-007 during infection of bean bug, Riptortus pedestris (Hemiptera: Alydidae).

    PubMed

    Yang, Yi-Ting; Lee, Se Jin; Nai, Yu-Shin; Kim, Sihyeon; Kim, Jae Su

    2016-10-01

    Beauveria bassiana (Bb) is used as an environment-friendly biopesticide. However, the molecular mechanisms of Bb-host interactions are not well understood. Herein, RNA isolated from B. bassiana (Bb JEF-007) and Riptortus pedestris (Hemiptera: Alydidae) infected with this strain were firstly subjected to high-throughput next generation sequencing (NGS) to analyze and compare transcriptomes. Due to lack of fungal and host genome information, fungal transcriptome was processed to partially exclude non-infection specific genes and host-flora. Differentially Expressed Gene (DEG) analysis showed that 2381 genes were up-regulated and 2303 genes were down-regulated upon infection. Most DEGs were classified into the categories of single-organism, cellular and metabolism processes by Gene Ontology analysis. Most DEGs were involved in metabolic pathways based on Kyoto Encyclopedia of Genes and Genomes pathway mapping. Carbon metabolism-related enzymes in the glyoxylate cycle were significantly up-regulated, suggesting a possible role for them in Bb growth in the host. Additionally, transcript levels of several fungal genes were dramatically increased after infection, such as cytotoxic lectin-like protein, bacterial-like toxin, proteins related to cell wall formation, hyphal growth, nutrient uptake, and halogenated compound synthesis. This work provides insight into how entomopathogenic B. bassiana grows in agriculturally harmful bean bug at 6 d post infection. PMID:27647240

  12. Safrole oxide induces apoptosis by up-regulating Fas and FasL instead of integrin beta4 in A549 human lung cancer cells.

    PubMed

    Du, AiYing; Zhao, BaoXiang; Miao, JunYing; Yin, DeLing; Zhang, ShangLi

    2006-04-01

    Previously, we found that 3,4-(methylenedioxy)-1-(2',3'-epoxypropyl)-benzene (safrole oxide) induced a typical apoptosis in A549 human lung cancer cells by activating caspase-3, -8, and -9. In this study, we further investigated which upstream pathways were activated by safrole oxide during the apoptosis. Immunofluorescence assay combined with laser scanning confocal microscopy revealed that both Fas and Fas ligand (FasL) were up-regulated by the small molecule. In addition, Fas protein distribution was altered, showing a clustering distribution instead of a homogeneous one. Subsequently, Western blot analysis confirmed the up-regulations of Fas and its membrane-binding form of FasL (m-FasL), as well as P53 protein. Conversely, safrole oxide hardly affected integrin beta4 subunit expression or distribution, which was reflected from the data obtained by immunofluorescence assay combined with laser scanning confocal microscopy. The results suggested that Fas/FasL pathway might be involved in safrole oxide-induced apoptosis of A549 cells, while integrin beta4 might be irrelevant to the apoptosis. Nevertheless, we first found the strong expression of integrin beta4 in A549 cells. The study first suggested that safrole oxide might be used as a small molecular promoter of Fas/FasL pathway to elicit apoptosis in A549 cells, which would lay the foundation for us to insight into the new strategies for lung cancer therapy.

  13. Up-regulation of Store-operated Ca2+ Entry and Nuclear Factor of Activated T Cells Promote the Acinar Phenotype of the Primary Human Salivary Gland Cells.

    PubMed

    Jang, Shyh-Ing; Ong, Hwei Ling; Liu, Xibao; Alevizos, Ilias; Ambudkar, Indu S

    2016-04-15

    The signaling pathways involved in the generation and maintenance of exocrine gland acinar cells have not yet been established. Primary human salivary gland epithelial cells, derived from salivary gland biopsies, acquired an acinar-like phenotype when the [Ca(2+)] in the serum-free medium (keratinocyte growth medium, KGM) was increased from 0.05 mm (KGM-L) to 1.2 mm (KGM-H). Here we examined the mechanism underlying this Ca(2+)-dependent generation of the acinar cell phenotype. Compared with cells in KGM-L, those in KGM-H display enhancement of Orai1, STIM1, STIM2, and nuclear factor of activated T cells 1 (NFAT1) expression together with an increase in store-operated Ca(2+) entry (SOCE), SOCE-dependent nuclear translocation of pGFP-NFAT1, and NFAT-dependent but not NFκB-dependent gene expression. Importantly, AQP5, an acinar-specific protein critical for function, is up-regulated in KGM-H via SOCE/NFAT-dependent gene expression. We identified critical NFAT binding motifs in the AQP5 promoter that are involved in Ca(2+)-dependent up-regulation of AQP5. These important findings reveal that the Ca(2+)-induced switch of salivary epithelial cells to an acinar-like phenotype involves remodeling of SOCE and NFAT signaling, which together control the expression of proteins critically relevant for acinar cell function. Our data provide a novel strategy for generating and maintaining acinar cells in culture.

  14. Melatonin-mediated Bim up-regulation and cyclooxygenase-2 (COX-2) down-regulation enhances tunicamycin-induced apoptosis in MDA-MB-231 cells.

    PubMed

    Woo, Seon Min; Min, Kyoung-jin; Kwon, Taeg Kyu

    2015-04-01

    Melatonin is involved in many physiological functions, and it has differential effects on apoptosis in normal and cancer cells. However, the mechanism of its antitumor roles is not well understood. In this study, we show that melatonin enhances tunicamycin-induced apoptosis in human breast carcinoma MDA-MB-231 cells. Melatonin up-regulates pro-apoptotic protein Bim expression at the transcriptional levels in the presence of tunicamycin. Melatonin inhibits tunicamycin-induced COX-2 expression in MDA-MB-231 cells. Furthermore, inhibition of COX-2 activity using the COX-2 inhibitor, NS398, increases tunicamycin-induced apoptosis. Interestingly, these effects were not associated with melatonin receptor signal pathways. Pertussis toxin (a general Gi protein inhibitor) or luzindole (a nonspecific melatonin receptor antagonist) did not reverse the effect of melatonin. In addition, melatonin blocked tunicamycin-induced NF-κB transcriptional activity, p65 nuclear translocation, and p38 MAPK activation. Melatonin-mediated p38 MAPK inhibition contributed to decreased COX-2 mRNA stability. Taken together, our results suggest that melatonin enhances antitumor function through up-regulation of Bim expression and down-regulation of COX-2 expression in tunicamycin-treated MDA-MB-231 cells. PMID:25711465

  15. Compassion-based emotion regulation up-regulates experienced positive affect and associated neural networks

    PubMed Central

    Singer, Tania

    2015-01-01

    Emotion regulation research has primarily focused on techniques that attenuate or modulate the impact of emotional stimuli. Recent evidence suggests that this mode regulation can be problematic in the context of regulation of emotion elicited by the suffering of others, resulting in reduced emotional connectedness. Here, we investigated the effects of an alternative emotion regulation technique based on the up-regulation of positive affect via Compassion-meditation on experiential and neural affective responses to depictions of individuals in distress, and compared these with the established emotion regulation strategy of Reappraisal. Using fMRI, we scanned 15 expert practitioners of Compassion-meditation either passively viewing, or using Compassion-meditation or Reappraisal to modulate their emotional reactions to film clips depicting people in distress. Both strategies effectively, but differentially regulated experienced affect, with Compassion primarily increasing positive and Reappraisal primarily decreasing negative affect. Imaging results showed that Compassion, relative to both passive-viewing and Reappraisal increased activation in regions involved in affiliation, positive affect and reward processing including ventral striatum and medial orbitfrontal cortex. This network was shown to be active prior to stimulus presentation, suggesting that the regulatory mechanism of Compassion is the stimulus-independent endogenous generation of positive affect. PMID:25698699

  16. Early up-regulation of chemokine expression in fulminant hepatic failure.

    PubMed

    Leifeld, Ludger; Dumoulin, Franz-Ludwig; Purr, Ingvill; Janberg, Katrin; Trautwein, Christian; Wolff, Martin; Manns, Michael Peter; Sauerbruch, Tilman; Spengler, Ulrich

    2003-03-01

    CC-chemokines recruit and activate macrophages and T lymphocytes, the major components of inflammatory infiltrates in fulminant hepatic failure (FHF). To analyse the role of CC-chemokines in the pathogenesis of FHF, this study examined serum levels and intrahepatic expression of MCP-1, MIP-1alpha, MIP-1beta, and RANTES in the livers and sera of patients with FHF and controls by ELISA, immunohistochemistry, and competitive RT-PCR. Serum levels and intrahepatic expression of all chemokines studied in FHF exceeded the levels in chronic liver diseases and normal controls. Distinct patterns of expression of each chemokine were noted on Kupffer cells, sinusoidal endothelial cells, hepatocytes, lymphocytes, and bile ducts. Intrahepatic chemokine expression correlated closely with the extent of infiltration by macrophages and T lymphocytes (r = 0.65-0.95, p < 0.001). The functional relationship between intrahepatic chemokine release and infiltration was confirmed in chemotaxis assays by inhibiting chemotaxis induced by homogenates of liver tissue obtained from FHF patients with neutralizing MCP-1, MIP-1alpha, MIP-1beta, and RANTES antibodies. The time course of CC-chemokine release was studied in the concanavalin A and the galactosamine/LPS mouse models of FHF. In both models, intrahepatic chemokine up-regulation occurred as an early event prior to hepatic infiltration and liver damage. The data indicate that an abundant intrahepatic release of CC-chemokines is an early and pivotal step in the pathogenesis of FHF.

  17. Hypoxia Up-Regulates Galectin-3 in Mammary Tumor Progression and Metastasis.

    PubMed

    de Oliveira, Joana T; Ribeiro, Cláudia; Barros, Rita; Gomes, Catarina; de Matos, Augusto J; Reis, Celso A; Rutteman, Gerard R; Gärtner, Fátima

    2015-01-01

    The tumor microenvironment encompasses several stressful conditions for cancer cells such as hypoxia, oxidative stress and pH alterations. Galectin-3, a well-studied member of the beta-galactoside-binding animal family of lectins has been implicated in multiple steps of metastasis as cell-cell and cell-ECM adhesion, promotion of angiogenesis, cell proliferation and resistance to apoptosis. However, both its aberrantly up- and down-regulated expression was observed in several types of cancer. Thus, the mechanisms that regulate galectin-3 expression in neoplastic settings are not clear. In order to demonstrate the putative role of hypoxia in regulating galectin-3 expression in canine mammary tumors (CMT), in vitro and in vivo studies were performed. In malignant CMT cells, hypoxia was observed to induce expression of galectin-3, a phenomenon that was almost completely prevented by catalase treatment of CMT-U27 cells. Increased galectin-3 expression was confirmed at the mRNA level. Under hypoxic conditions the expression of galectin-3 shifts from a predominant nuclear location to cytoplasmic and membrane expressions. In in vivo studies, galectin-3 was overexpressed in hypoxic areas of primary tumors and well-established metastases. Tumor hypoxia thus up-regulates the expression of galectin-3, which may in turn increase tumor aggressiveness. PMID:26222311

  18. Compassion-based emotion regulation up-regulates experienced positive affect and associated neural networks.

    PubMed

    Engen, Haakon G; Singer, Tania

    2015-09-01

    Emotion regulation research has primarily focused on techniques that attenuate or modulate the impact of emotional stimuli. Recent evidence suggests that this mode regulation can be problematic in the context of regulation of emotion elicited by the suffering of others, resulting in reduced emotional connectedness. Here, we investigated the effects of an alternative emotion regulation technique based on the up-regulation of positive affect via Compassion-meditation on experiential and neural affective responses to depictions of individuals in distress, and compared these with the established emotion regulation strategy of Reappraisal. Using fMRI, we scanned 15 expert practitioners of Compassion-meditation either passively viewing, or using Compassion-meditation or Reappraisal to modulate their emotional reactions to film clips depicting people in distress. Both strategies effectively, but differentially regulated experienced affect, with Compassion primarily increasing positive and Reappraisal primarily decreasing negative affect. Imaging results showed that Compassion, relative to both passive-viewing and Reappraisal increased activation in regions involved in affiliation, positive affect and reward processing including ventral striatum and medial orbitfrontal cortex. This network was shown to be active prior to stimulus presentation, suggesting that the regulatory mechanism of Compassion is the stimulus-independent endogenous generation of positive affect. PMID:25698699

  19. Compassion-based emotion regulation up-regulates experienced positive affect and associated neural networks.

    PubMed

    Engen, Haakon G; Singer, Tania

    2015-09-01

    Emotion regulation research has primarily focused on techniques that attenuate or modulate the impact of emotional stimuli. Recent evidence suggests that this mode regulation can be problematic in the context of regulation of emotion elicited by the suffering of others, resulting in reduced emotional connectedness. Here, we investigated the effects of an alternative emotion regulation technique based on the up-regulation of positive affect via Compassion-meditation on experiential and neural affective responses to depictions of individuals in distress, and compared these with the established emotion regulation strategy of Reappraisal. Using fMRI, we scanned 15 expert practitioners of Compassion-meditation either passively viewing, or using Compassion-meditation or Reappraisal to modulate their emotional reactions to film clips depicting people in distress. Both strategies effectively, but differentially regulated experienced affect, with Compassion primarily increasing positive and Reappraisal primarily decreasing negative affect. Imaging results showed that Compassion, relative to both passive-viewing and Reappraisal increased activation in regions involved in affiliation, positive affect and reward processing including ventral striatum and medial orbitfrontal cortex. This network was shown to be active prior to stimulus presentation, suggesting that the regulatory mechanism of Compassion is the stimulus-independent endogenous generation of positive affect.

  20. Centenarians, but not octogenarians, up-regulate the expression of microRNAs.

    PubMed

    Serna, Eva; Gambini, Juan; Borras, Consuelo; Abdelaziz, Kheira M; Mohammed, Kheira; Belenguer, Angel; Sanchis, Paula; Avellana, Juan A; Rodriguez-Mañas, Leocadio; Viña, Jose

    2012-01-01

    Centenarians exhibit extreme longevity and a remarkable compression of morbidity. They have a unique capacity to maintain homeostatic mechanisms. Since small non-coding RNAs (including microRNAs) are implicated in the regulation of gene expression, we hypothesised that longevity of centenarians may reflect alterations in small non-coding RNA expression. We report the first comparison of microRNAs expression profiles in mononuclear cells from centenarians, octogenarians and young individuals resident near Valencia, Spain. Principal Component Analysis of the expression of 15,644 mature microRNAs and, 2,334 snoRNAs and scaRNAs in centenarians revealed a significant overlap with profiles in young individuals but not with octogenarians and a significant up-regulation of 7 small non-coding RNAs in centenarians compared to young persons and notably 102 small non-coding RNAs when compared with octogenarians. We suggest that the small non-coding RNAs signature in centenarians may provide insights into the underlying molecular mechanisms endowing centenarians with extreme longevity.